+++ /dev/null
-/*
- * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
- * Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved.
- * Copyright (c) 1996-1999 by Silicon Graphics. All rights reserved.
- * Copyright (c) 1999 by Hewlett-Packard Company. All rights reserved.
- *
- * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
- * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
- *
- * Permission is hereby granted to use or copy this program
- * for any purpose, provided the above notices are retained on all copies.
- * Permission to modify the code and to distribute modified code is granted,
- * provided the above notices are retained, and a notice that the code was
- * modified is included with the above copyright notice.
- */
-
-#include "private/gc_priv.h"
-
-#if defined(LINUX) && !defined(POWERPC)
-# include <linux/version.h>
-# if (LINUX_VERSION_CODE <= 0x10400)
- /* Ugly hack to get struct sigcontext_struct definition. Required */
- /* for some early 1.3.X releases. Will hopefully go away soon. */
- /* in some later Linux releases, asm/sigcontext.h may have to */
- /* be included instead. */
-# define __KERNEL__
-# include <asm/signal.h>
-# undef __KERNEL__
-# else
- /* Kernels prior to 2.1.1 defined struct sigcontext_struct instead of */
- /* struct sigcontext. libc6 (glibc2) uses "struct sigcontext" in */
- /* prototypes, so we have to include the top-level sigcontext.h to */
- /* make sure the former gets defined to be the latter if appropriate. */
-# include <features.h>
-# if 2 <= __GLIBC__
-# if 2 == __GLIBC__ && 0 == __GLIBC_MINOR__
- /* glibc 2.1 no longer has sigcontext.h. But signal.h */
- /* has the right declaration for glibc 2.1. */
-# include <sigcontext.h>
-# endif /* 0 == __GLIBC_MINOR__ */
-# else /* not 2 <= __GLIBC__ */
- /* libc5 doesn't have <sigcontext.h>: go directly with the kernel */
- /* one. Check LINUX_VERSION_CODE to see which we should reference. */
-# include <asm/sigcontext.h>
-# endif /* 2 <= __GLIBC__ */
-# endif
-#endif
-
-#if !defined(OS2) && !defined(PCR) && !defined(AMIGA) && !defined(MACOS) \
- && !defined(MSWINCE)
-# include <sys/types.h>
-# if !defined(MSWIN32)
-# include <unistd.h>
-# endif
-#endif
-
-#include <stdio.h>
-#if defined(MSWINCE)
-# define SIGSEGV 0 /* value is irrelevant */
-#else
-# include <signal.h>
-#endif
-
-#if defined(UNIX_LIKE) || defined(CYGWIN32)
-# include <fcntl.h>
-#endif
-
-#if defined(LINUX) || defined(LINUX_STACKBOTTOM)
-# include <ctype.h>
-#endif
-
-/* Blatantly OS dependent routines, except for those that are related */
-/* to dynamic loading. */
-
-#ifdef AMIGA
-# define GC_AMIGA_DEF
-# include "extra/AmigaOS.c"
-# undef GC_AMIGA_DEF
-#endif
-
-#if defined(MSWIN32) || defined(MSWINCE) || defined(CYGWIN32)
-# ifndef WIN32_LEAN_AND_MEAN
-# define WIN32_LEAN_AND_MEAN 1
-# endif
-# define NOSERVICE
-# include <windows.h>
- /* It's not clear this is completely kosher under Cygwin. But it */
- /* allows us to get a working GC_get_stack_base. */
-#endif
-
-#ifdef MACOS
-# include <Processes.h>
-#endif
-
-#ifdef IRIX5
-# include <sys/uio.h>
-# include <malloc.h> /* for locking */
-#endif
-
-#if defined(LINUX) || defined(FREEBSD) || defined(SOLARIS) || defined(IRIX5) \
- || ((defined(USE_MMAP) || defined(USE_MUNMAP)) \
- && !defined(MSWIN32) && !defined(MSWINCE))
-# define MMAP_SUPPORTED
-#endif
-
-#if defined(MMAP_SUPPORTED) || defined(ADD_HEAP_GUARD_PAGES)
-# if defined(USE_MUNMAP) && !defined(USE_MMAP)
-# error "invalid config - USE_MUNMAP requires USE_MMAP"
-# endif
-# include <sys/types.h>
-# include <sys/mman.h>
-# include <sys/stat.h>
-# include <errno.h>
-#endif
-
-#ifdef DARWIN
- /* for get_etext and friends */
-# include <mach-o/getsect.h>
-#endif
-
-#ifdef DJGPP
- /* Apparently necessary for djgpp 2.01. May cause problems with */
- /* other versions. */
- typedef long unsigned int caddr_t;
-#endif
-
-#ifdef PCR
-# include "il/PCR_IL.h"
-# include "th/PCR_ThCtl.h"
-# include "mm/PCR_MM.h"
-#endif
-
-#if !defined(NO_EXECUTE_PERMISSION)
-# define OPT_PROT_EXEC PROT_EXEC
-#else
-# define OPT_PROT_EXEC 0
-#endif
-
-#if defined(LINUX) && (defined(USE_PROC_FOR_LIBRARIES) || defined(IA64) \
- || !defined(SMALL_CONFIG))
-# define NEED_PROC_MAPS
-#endif
-
-#ifdef NEED_PROC_MAPS
-/* We need to parse /proc/self/maps, either to find dynamic libraries, */
-/* and/or to find the register backing store base (IA64). Do it once */
-/* here. */
-
-#define READ read
-
-/* Repeatedly perform a read call until the buffer is filled or */
-/* we encounter EOF. */
-STATIC ssize_t GC_repeat_read(int fd, char *buf, size_t count)
-{
- ssize_t num_read = 0;
- ssize_t result;
-
- ASSERT_CANCEL_DISABLED();
- while (num_read < count) {
- result = READ(fd, buf + num_read, count - num_read);
- if (result < 0) return result;
- if (result == 0) break;
- num_read += result;
- }
- return num_read;
-}
-
-#ifdef THREADS
- /* Determine the length of a file by incrementally reading it into a */
- /* This would be silly to use on a file supporting lseek, but Linux */
- /* /proc files usually do not. */
- STATIC size_t GC_get_file_len(int f)
- {
- size_t total = 0;
- ssize_t result;
-# define GET_FILE_LEN_BUF_SZ 500
- char buf[GET_FILE_LEN_BUF_SZ];
-
- do {
- result = read(f, buf, GET_FILE_LEN_BUF_SZ);
- if (result == -1) return 0;
- total += result;
- } while (result > 0);
- return total;
- }
-
- STATIC size_t GC_get_maps_len(void)
- {
- int f = open("/proc/self/maps", O_RDONLY);
- size_t result = GC_get_file_len(f);
- close(f);
- return result;
- }
-#endif /* THREADS */
-
-/*
- * Copy the contents of /proc/self/maps to a buffer in our address space.
- * Return the address of the buffer, or zero on failure.
- * This code could be simplified if we could determine its size
- * ahead of time.
- */
-GC_INNER char * GC_get_maps(void)
-{
- int f;
- int result;
- static char init_buf[1];
- static char *maps_buf = init_buf;
- static size_t maps_buf_sz = 1;
- size_t maps_size, old_maps_size = 0;
-
- /* The buffer is essentially static, so there must be a single client. */
- GC_ASSERT(I_HOLD_LOCK());
-
- /* Note that in the presence of threads, the maps file can */
- /* essentially shrink asynchronously and unexpectedly as */
- /* threads that we already think of as dead release their */
- /* stacks. And there is no easy way to read the entire */
- /* file atomically. This is arguably a misfeature of the */
- /* /proc/.../maps interface. */
-
- /* Since we don't believe the file can grow */
- /* asynchronously, it should suffice to first determine */
- /* the size (using lseek or read), and then to reread the */
- /* file. If the size is inconsistent we have to retry. */
- /* This only matters with threads enabled, and if we use */
- /* this to locate roots (not the default). */
-
- /* Determine the initial size of /proc/self/maps. */
- /* Note that lseek doesn't work, at least as of 2.6.15. */
-# ifdef THREADS
- maps_size = GC_get_maps_len();
- if (0 == maps_size) return 0;
-# else
- maps_size = 4000; /* Guess */
-# endif
-
- /* Read /proc/self/maps, growing maps_buf as necessary. */
- /* Note that we may not allocate conventionally, and */
- /* thus can't use stdio. */
- do {
- while (maps_size >= maps_buf_sz) {
- /* Grow only by powers of 2, since we leak "too small" buffers. */
- while (maps_size >= maps_buf_sz) maps_buf_sz *= 2;
- maps_buf = GC_scratch_alloc(maps_buf_sz);
-# ifdef THREADS
- /* Recompute initial length, since we allocated. */
- /* This can only happen a few times per program */
- /* execution. */
- maps_size = GC_get_maps_len();
- if (0 == maps_size) return 0;
-# endif
- if (maps_buf == 0) return 0;
- }
- GC_ASSERT(maps_buf_sz >= maps_size + 1);
- f = open("/proc/self/maps", O_RDONLY);
- if (-1 == f) return 0;
-# ifdef THREADS
- old_maps_size = maps_size;
-# endif
- maps_size = 0;
- do {
- result = GC_repeat_read(f, maps_buf, maps_buf_sz-1);
- if (result <= 0) return 0;
- maps_size += result;
- } while (result == maps_buf_sz-1);
- close(f);
-# ifdef THREADS
- if (maps_size > old_maps_size) {
- GC_err_printf("Old maps size = %lu, new maps size = %lu\n",
- (unsigned long)old_maps_size,
- (unsigned long)maps_size);
- ABORT("Unexpected asynchronous /proc/self/maps growth: "
- "Unregistered thread?");
- }
-# endif
- } while (maps_size >= maps_buf_sz || maps_size < old_maps_size);
- /* In the single-threaded case, the second clause is false. */
- maps_buf[maps_size] = '\0';
-
- /* Apply fn to result. */
- return maps_buf;
-}
-
-/*
- * GC_parse_map_entry parses an entry from /proc/self/maps so we can
- * locate all writable data segments that belong to shared libraries.
- * The format of one of these entries and the fields we care about
- * is as follows:
- * XXXXXXXX-XXXXXXXX r-xp 00000000 30:05 260537 name of mapping...\n
- * ^^^^^^^^ ^^^^^^^^ ^^^^ ^^
- * start end prot maj_dev
- *
- * Note that since about august 2003 kernels, the columns no longer have
- * fixed offsets on 64-bit kernels. Hence we no longer rely on fixed offsets
- * anywhere, which is safer anyway.
- */
-
-/*
- * Assign various fields of the first line in buf_ptr to *start, *end,
- * *prot, *maj_dev and *mapping_name. Mapping_name may be NULL.
- * *prot and *mapping_name are assigned pointers into the original
- * buffer.
- */
-GC_INNER char *GC_parse_map_entry(char *buf_ptr, ptr_t *start, ptr_t *end,
- char **prot, unsigned int *maj_dev,
- char **mapping_name)
-{
- char *start_start, *end_start, *maj_dev_start;
- char *p;
- char *endp;
-
- if (buf_ptr == NULL || *buf_ptr == '\0') {
- return NULL;
- }
-
- p = buf_ptr;
- while (isspace(*p)) ++p;
- start_start = p;
- GC_ASSERT(isxdigit(*start_start));
- *start = (ptr_t)strtoul(start_start, &endp, 16); p = endp;
- GC_ASSERT(*p=='-');
-
- ++p;
- end_start = p;
- GC_ASSERT(isxdigit(*end_start));
- *end = (ptr_t)strtoul(end_start, &endp, 16); p = endp;
- GC_ASSERT(isspace(*p));
-
- while (isspace(*p)) ++p;
- GC_ASSERT(*p == 'r' || *p == '-');
- *prot = p;
- /* Skip past protection field to offset field */
- while (!isspace(*p)) ++p; while (isspace(*p)) ++p;
- GC_ASSERT(isxdigit(*p));
- /* Skip past offset field, which we ignore */
- while (!isspace(*p)) ++p; while (isspace(*p)) ++p;
- maj_dev_start = p;
- GC_ASSERT(isxdigit(*maj_dev_start));
- *maj_dev = strtoul(maj_dev_start, NULL, 16);
-
- if (mapping_name == 0) {
- while (*p && *p++ != '\n');
- } else {
- while (*p && *p != '\n' && *p != '/' && *p != '[') p++;
- *mapping_name = p;
- while (*p && *p++ != '\n');
- }
-
- return p;
-}
-
-/* Try to read the backing store base from /proc/self/maps. */
-/* Return the bounds of the writable mapping with a 0 major device, */
-/* which includes the address passed as data. */
-/* Return FALSE if there is no such mapping. */
-GC_bool GC_enclosing_mapping(ptr_t addr, ptr_t *startp, ptr_t *endp)
-{
- char *prot;
- ptr_t my_start, my_end;
- unsigned int maj_dev;
- char *maps = GC_get_maps();
- char *buf_ptr = maps;
-
- if (0 == maps) return(FALSE);
- for (;;) {
- buf_ptr = GC_parse_map_entry(buf_ptr, &my_start, &my_end,
- &prot, &maj_dev, 0);
-
- if (buf_ptr == NULL) return FALSE;
- if (prot[1] == 'w' && maj_dev == 0) {
- if (my_end > addr && my_start <= addr) {
- *startp = my_start;
- *endp = my_end;
- return TRUE;
- }
- }
- }
- return FALSE;
-}
-
-#if defined(REDIRECT_MALLOC)
-/* Find the text(code) mapping for the library whose name, after */
-/* stripping the directory part, starts with nm. */
-GC_INNER GC_bool GC_text_mapping(char *nm, ptr_t *startp, ptr_t *endp)
-{
- size_t nm_len = strlen(nm);
- char *prot;
- char *map_path;
- ptr_t my_start, my_end;
- unsigned int maj_dev;
- char *maps = GC_get_maps();
- char *buf_ptr = maps;
-
- if (0 == maps) return(FALSE);
- for (;;) {
- buf_ptr = GC_parse_map_entry(buf_ptr, &my_start, &my_end,
- &prot, &maj_dev, &map_path);
-
- if (buf_ptr == NULL) return FALSE;
- if (prot[0] == 'r' && prot[1] == '-' && prot[2] == 'x') {
- char *p = map_path;
- /* Set p to point just past last slash, if any. */
- while (*p != '\0' && *p != '\n' && *p != ' ' && *p != '\t') ++p;
- while (*p != '/' && p >= map_path) --p;
- ++p;
- if (strncmp(nm, p, nm_len) == 0) {
- *startp = my_start;
- *endp = my_end;
- return TRUE;
- }
- }
- }
- return FALSE;
-}
-#endif /* REDIRECT_MALLOC */
-
-#ifdef IA64
- static ptr_t backing_store_base_from_proc(void)
- {
- ptr_t my_start, my_end;
- if (!GC_enclosing_mapping(GC_save_regs_in_stack(), &my_start, &my_end)) {
- if (GC_print_stats) {
- GC_log_printf("Failed to find backing store base from /proc\n");
- }
- return 0;
- }
- return my_start;
- }
-#endif
-
-#endif /* NEED_PROC_MAPS */
-
-#if defined(SEARCH_FOR_DATA_START)
- /* The I386 case can be handled without a search. The Alpha case */
- /* used to be handled differently as well, but the rules changed */
- /* for recent Linux versions. This seems to be the easiest way to */
- /* cover all versions. */
-
-# if defined(LINUX) || defined(HURD)
- /* Some Linux distributions arrange to define __data_start. Some */
- /* define data_start as a weak symbol. The latter is technically */
- /* broken, since the user program may define data_start, in which */
- /* case we lose. Nonetheless, we try both, preferring __data_start.*/
- /* We assume gcc-compatible pragmas. */
-# pragma weak __data_start
- extern int __data_start[];
-# pragma weak data_start
- extern int data_start[];
-# endif /* LINUX */
- extern int _end[];
-
- ptr_t GC_data_start = NULL;
-
- ptr_t GC_find_limit(ptr_t, GC_bool);
-
- GC_INNER void GC_init_linux_data_start(void)
- {
-
-# if defined(LINUX) || defined(HURD)
- /* Try the easy approaches first: */
- if ((ptr_t)__data_start != 0) {
- GC_data_start = (ptr_t)(__data_start);
- return;
- }
- if ((ptr_t)data_start != 0) {
- GC_data_start = (ptr_t)(data_start);
- return;
- }
-# endif /* LINUX */
- GC_data_start = GC_find_limit((ptr_t)(_end), FALSE);
- }
-#endif
-
-# ifdef ECOS
-
-# ifndef ECOS_GC_MEMORY_SIZE
-# define ECOS_GC_MEMORY_SIZE (448 * 1024)
-# endif /* ECOS_GC_MEMORY_SIZE */
-
-/* FIXME: This is a simple way of allocating memory which is */
-/* compatible with ECOS early releases. Later releases use a more */
-/* sophisticated means of allocating memory than this simple static */
-/* allocator, but this method is at least bound to work. */
-static char ecos_gc_memory[ECOS_GC_MEMORY_SIZE];
-static char *ecos_gc_brk = ecos_gc_memory;
-
-static void *tiny_sbrk(ptrdiff_t increment)
-{
- void *p = ecos_gc_brk;
- ecos_gc_brk += increment;
- if (ecos_gc_brk > ecos_gc_memory + sizeof(ecos_gc_memory)) {
- ecos_gc_brk -= increment;
- return NULL;
- }
- return p;
-}
-#define sbrk tiny_sbrk
-# endif /* ECOS */
-
-#if defined(NETBSD) && defined(__ELF__)
- ptr_t GC_data_start = NULL;
- ptr_t GC_find_limit(ptr_t, GC_bool);
-
- extern char **environ;
-
- GC_INNER void GC_init_netbsd_elf(void)
- {
- /* This may need to be environ, without the underscore, for */
- /* some versions. */
- GC_data_start = GC_find_limit((ptr_t)&environ, FALSE);
- }
-#endif
-
-#ifdef OPENBSD
- static struct sigaction old_segv_act;
- STATIC sigjmp_buf GC_jmp_buf_openbsd;
-
-# ifdef THREADS
-# include <sys/syscall.h>
- extern sigset_t __syscall(quad_t, ...);
-# endif
-
- /* Don't use GC_find_limit() because siglongjmp() outside of the */
- /* signal handler by-passes our userland pthreads lib, leaving */
- /* SIGSEGV and SIGPROF masked. Instead, use this custom one that */
- /* works-around the issues. */
-
- /*ARGSUSED*/
- STATIC void GC_fault_handler_openbsd(int sig)
- {
- siglongjmp(GC_jmp_buf_openbsd, 1);
- }
-
- /* Return the first non-addressible location > p or bound. */
- /* Requires the allocation lock. */
- STATIC ptr_t GC_find_limit_openbsd(ptr_t p, ptr_t bound)
- {
- static volatile ptr_t result;
- /* Safer if static, since otherwise it may not be */
- /* preserved across the longjmp. Can safely be */
- /* static since it's only called with the */
- /* allocation lock held. */
-
- struct sigaction act;
- size_t pgsz = (size_t)sysconf(_SC_PAGESIZE);
- GC_ASSERT(I_HOLD_LOCK());
-
- act.sa_handler = GC_fault_handler_openbsd;
- sigemptyset(&act.sa_mask);
- act.sa_flags = SA_NODEFER | SA_RESTART;
- sigaction(SIGSEGV, &act, &old_segv_act);
-
- if (sigsetjmp(GC_jmp_buf_openbsd, 1) == 0) {
- result = (ptr_t)((word)p & ~(pgsz-1));
- for (;;) {
- result += pgsz;
- if (result >= bound) {
- result = bound;
- break;
- }
- GC_noop1((word)(*result));
- }
- }
-
-# ifdef THREADS
- /* Due to the siglongjump we need to manually unmask SIGPROF. */
- __syscall(SYS_sigprocmask, SIG_UNBLOCK, sigmask(SIGPROF));
-# endif
-
- sigaction(SIGSEGV, &old_segv_act, 0);
- return(result);
- }
-
- /* Return first addressable location > p or bound. */
- /* Requires the allocation lock. */
- STATIC ptr_t GC_skip_hole_openbsd(ptr_t p, ptr_t bound)
- {
- static volatile ptr_t result;
- static volatile int firstpass;
-
- struct sigaction act;
- size_t pgsz = (size_t)sysconf(_SC_PAGESIZE);
- GC_ASSERT(I_HOLD_LOCK());
-
- act.sa_handler = GC_fault_handler_openbsd;
- sigemptyset(&act.sa_mask);
- act.sa_flags = SA_NODEFER | SA_RESTART;
- sigaction(SIGSEGV, &act, &old_segv_act);
-
- firstpass = 1;
- result = (ptr_t)((word)p & ~(pgsz-1));
- if (sigsetjmp(GC_jmp_buf_openbsd, 1) != 0 || firstpass) {
- firstpass = 0;
- result += pgsz;
- if (result >= bound) {
- result = bound;
- } else {
- GC_noop1((word)(*result));
- }
- }
-
- sigaction(SIGSEGV, &old_segv_act, 0);
- return(result);
- }
-#endif /* OPENBSD */
-
-# ifdef OS2
-
-# include <stddef.h>
-
-# if !defined(__IBMC__) && !defined(__WATCOMC__) /* e.g. EMX */
-
-struct exe_hdr {
- unsigned short magic_number;
- unsigned short padding[29];
- long new_exe_offset;
-};
-
-#define E_MAGIC(x) (x).magic_number
-#define EMAGIC 0x5A4D
-#define E_LFANEW(x) (x).new_exe_offset
-
-struct e32_exe {
- unsigned char magic_number[2];
- unsigned char byte_order;
- unsigned char word_order;
- unsigned long exe_format_level;
- unsigned short cpu;
- unsigned short os;
- unsigned long padding1[13];
- unsigned long object_table_offset;
- unsigned long object_count;
- unsigned long padding2[31];
-};
-
-#define E32_MAGIC1(x) (x).magic_number[0]
-#define E32MAGIC1 'L'
-#define E32_MAGIC2(x) (x).magic_number[1]
-#define E32MAGIC2 'X'
-#define E32_BORDER(x) (x).byte_order
-#define E32LEBO 0
-#define E32_WORDER(x) (x).word_order
-#define E32LEWO 0
-#define E32_CPU(x) (x).cpu
-#define E32CPU286 1
-#define E32_OBJTAB(x) (x).object_table_offset
-#define E32_OBJCNT(x) (x).object_count
-
-struct o32_obj {
- unsigned long size;
- unsigned long base;
- unsigned long flags;
- unsigned long pagemap;
- unsigned long mapsize;
- unsigned long reserved;
-};
-
-#define O32_FLAGS(x) (x).flags
-#define OBJREAD 0x0001L
-#define OBJWRITE 0x0002L
-#define OBJINVALID 0x0080L
-#define O32_SIZE(x) (x).size
-#define O32_BASE(x) (x).base
-
-# else /* IBM's compiler */
-
-/* A kludge to get around what appears to be a header file bug */
-# ifndef WORD
-# define WORD unsigned short
-# endif
-# ifndef DWORD
-# define DWORD unsigned long
-# endif
-
-# define EXE386 1
-# include <newexe.h>
-# include <exe386.h>
-
-# endif /* __IBMC__ */
-
-# define INCL_DOSEXCEPTIONS
-# define INCL_DOSPROCESS
-# define INCL_DOSERRORS
-# define INCL_DOSMODULEMGR
-# define INCL_DOSMEMMGR
-# include <os2.h>
-
-# endif /* OS/2 */
-
-/* Find the page size */
-GC_INNER word GC_page_size = 0;
-
-# if defined(MSWIN32) || defined(MSWINCE)
-
-# ifndef VER_PLATFORM_WIN32_CE
-# define VER_PLATFORM_WIN32_CE 3
-# endif
-
-# if defined(MSWINCE) && defined(THREADS)
- GC_INNER GC_bool GC_dont_query_stack_min = FALSE;
-# endif
-
- GC_INNER void GC_setpagesize(void)
- {
- GetSystemInfo(&GC_sysinfo);
- GC_page_size = GC_sysinfo.dwPageSize;
-# if defined(MSWINCE) && !defined(_WIN32_WCE_EMULATION)
- {
- OSVERSIONINFO verInfo;
- /* Check the current WinCE version. */
- verInfo.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
- if (!GetVersionEx(&verInfo))
- ABORT("GetVersionEx failed");
- if (verInfo.dwPlatformId == VER_PLATFORM_WIN32_CE &&
- verInfo.dwMajorVersion < 6) {
- /* Only the first 32 MB of address space belongs to the */
- /* current process (unless WinCE 6.0+ or emulation). */
- GC_sysinfo.lpMaximumApplicationAddress = (LPVOID)((word)32 << 20);
-# ifdef THREADS
- /* On some old WinCE versions, it's observed that */
- /* VirtualQuery calls don't work properly when used to */
- /* get thread current stack committed minimum. */
- if (verInfo.dwMajorVersion < 5)
- GC_dont_query_stack_min = TRUE;
-# endif
- }
- }
-# endif
- }
-
-# else
- GC_INNER void GC_setpagesize(void)
- {
-# if defined(MPROTECT_VDB) || defined(PROC_VDB) || defined(USE_MMAP)
- GC_page_size = GETPAGESIZE();
-# else
- /* It's acceptable to fake it. */
- GC_page_size = HBLKSIZE;
-# endif
- }
-# endif
-
-# if defined(MSWIN32) || defined(MSWINCE) || defined(CYGWIN32)
-
-#ifndef CYGWIN32
-
-# define is_writable(prot) ((prot) == PAGE_READWRITE \
- || (prot) == PAGE_WRITECOPY \
- || (prot) == PAGE_EXECUTE_READWRITE \
- || (prot) == PAGE_EXECUTE_WRITECOPY)
-/* Return the number of bytes that are writable starting at p. */
-/* The pointer p is assumed to be page aligned. */
-/* If base is not 0, *base becomes the beginning of the */
-/* allocation region containing p. */
-STATIC word GC_get_writable_length(ptr_t p, ptr_t *base)
-{
- MEMORY_BASIC_INFORMATION buf;
- word result;
- word protect;
-
- result = VirtualQuery(p, &buf, sizeof(buf));
- if (result != sizeof(buf)) ABORT("Weird VirtualQuery result");
- if (base != 0) *base = (ptr_t)(buf.AllocationBase);
- protect = (buf.Protect & ~(PAGE_GUARD | PAGE_NOCACHE));
- if (!is_writable(protect)) {
- return(0);
- }
- if (buf.State != MEM_COMMIT) return(0);
- return(buf.RegionSize);
-}
-
-GC_API int GC_CALL GC_get_stack_base(struct GC_stack_base *sb)
-{
- int dummy;
- ptr_t sp = (ptr_t)(&dummy);
- ptr_t trunc_sp = (ptr_t)((word)sp & ~(GC_page_size - 1));
- /* FIXME: This won't work if called from a deeply recursive */
- /* client code (and the committed stack space has grown). */
- word size = GC_get_writable_length(trunc_sp, 0);
- GC_ASSERT(size != 0);
- sb -> mem_base = trunc_sp + size;
- return GC_SUCCESS;
-}
-
-#else /* CYGWIN32 */
-
-/* An alternate version for Cygwin (adapted from Dave Korn's */
-/* gcc version of boehm-gc). */
- GC_API int GC_CALL GC_get_stack_base(struct GC_stack_base *sb)
- {
- extern void * _tlsbase __asm__ ("%fs:4");
- sb -> mem_base = _tlsbase;
- return GC_SUCCESS;
- }
-
-#endif /* CYGWIN32 */
-
-# define HAVE_GET_STACK_BASE
-
-/* This is always called from the main thread. */
-ptr_t GC_get_main_stack_base(void)
-{
- struct GC_stack_base sb;
- GC_get_stack_base(&sb);
- GC_ASSERT((void *)&sb HOTTER_THAN sb.mem_base);
- return (ptr_t)sb.mem_base;
-}
-
-# endif /* MS Windows */
-
-# ifdef BEOS
-# include <kernel/OS.h>
- ptr_t GC_get_main_stack_base(void)
- {
- thread_info th;
- get_thread_info(find_thread(NULL),&th);
- return th.stack_end;
- }
-# endif /* BEOS */
-
-
-# ifdef OS2
-
-ptr_t GC_get_main_stack_base(void)
-{
- PTIB ptib;
- PPIB ppib;
-
- if (DosGetInfoBlocks(&ptib, &ppib) != NO_ERROR) {
- GC_err_printf("DosGetInfoBlocks failed\n");
- ABORT("DosGetInfoBlocks failed\n");
- }
- return((ptr_t)(ptib -> tib_pstacklimit));
-}
-
-# endif /* OS2 */
-
-# ifdef AMIGA
-# define GC_AMIGA_SB
-# include "extra/AmigaOS.c"
-# undef GC_AMIGA_SB
-# endif /* AMIGA */
-
-# if defined(NEED_FIND_LIMIT) || defined(UNIX_LIKE)
-
- typedef void (*GC_fault_handler_t)(int);
-
-# if defined(SUNOS5SIGS) || defined(IRIX5) || defined(OSF1) \
- || defined(HURD) || defined(NETBSD)
- static struct sigaction old_segv_act;
-# if defined(_sigargs) /* !Irix6.x */ || defined(HPUX) \
- || defined(HURD) || defined(NETBSD) || defined(FREEBSD)
- static struct sigaction old_bus_act;
-# endif
-# else
- static GC_fault_handler_t old_segv_handler, old_bus_handler;
-# endif
-
- GC_INNER void GC_set_and_save_fault_handler(GC_fault_handler_t h)
- {
-# if defined(SUNOS5SIGS) || defined(IRIX5) \
- || defined(OSF1) || defined(HURD) || defined(NETBSD)
- struct sigaction act;
-
- act.sa_handler = h;
-# if 0 /* Was necessary for Solaris 2.3 and very temporary */
- /* NetBSD bugs. */
- act.sa_flags = SA_RESTART | SA_NODEFER;
-# else
- act.sa_flags = SA_RESTART;
-# endif
-
- (void) sigemptyset(&act.sa_mask);
-# ifdef GC_IRIX_THREADS
- /* Older versions have a bug related to retrieving and */
- /* and setting a handler at the same time. */
- (void) sigaction(SIGSEGV, 0, &old_segv_act);
- (void) sigaction(SIGSEGV, &act, 0);
-# else
- (void) sigaction(SIGSEGV, &act, &old_segv_act);
-# if defined(IRIX5) && defined(_sigargs) /* Irix 5.x, not 6.x */ \
- || defined(HPUX) || defined(HURD) || defined(NETBSD) \
- || defined(FREEBSD)
- /* Under Irix 5.x or HP/UX, we may get SIGBUS. */
- /* Pthreads doesn't exist under Irix 5.x, so we */
- /* don't have to worry in the threads case. */
- (void) sigaction(SIGBUS, &act, &old_bus_act);
-# endif
-# endif /* GC_IRIX_THREADS */
-# else
- old_segv_handler = signal(SIGSEGV, h);
-# ifdef SIGBUS
- old_bus_handler = signal(SIGBUS, h);
-# endif
-# endif
- }
-# endif /* NEED_FIND_LIMIT || UNIX_LIKE */
-
-# if defined(NEED_FIND_LIMIT) || \
- defined(USE_PROC_FOR_LIBRARIES) && defined(THREADS)
- /* Some tools to implement HEURISTIC2 */
-# define MIN_PAGE_SIZE 256 /* Smallest conceivable page size, bytes */
-
- /*ARGSUSED*/
- STATIC void GC_fault_handler(int sig)
- {
- LONGJMP(GC_jmp_buf, 1);
- }
-
- GC_INNER void GC_setup_temporary_fault_handler(void)
- {
- /* Handler is process-wide, so this should only happen in */
- /* one thread at a time. */
- GC_ASSERT(I_HOLD_LOCK());
- GC_set_and_save_fault_handler(GC_fault_handler);
- }
-
- GC_INNER void GC_reset_fault_handler(void)
- {
-# if defined(SUNOS5SIGS) || defined(IRIX5) \
- || defined(OSF1) || defined(HURD) || defined(NETBSD)
- (void) sigaction(SIGSEGV, &old_segv_act, 0);
-# if defined(IRIX5) && defined(_sigargs) /* Irix 5.x, not 6.x */ \
- || defined(HPUX) || defined(HURD) || defined(NETBSD) \
- || defined(FREEBSD)
- (void) sigaction(SIGBUS, &old_bus_act, 0);
-# endif
-# else
- (void) signal(SIGSEGV, old_segv_handler);
-# ifdef SIGBUS
- (void) signal(SIGBUS, old_bus_handler);
-# endif
-# endif
- }
-
- /* Return the first non-addressable location > p (up) or */
- /* the smallest location q s.t. [q,p) is addressable (!up). */
- /* We assume that p (up) or p-1 (!up) is addressable. */
- /* Requires allocation lock. */
- STATIC ptr_t GC_find_limit_with_bound(ptr_t p, GC_bool up, ptr_t bound)
- {
- static volatile ptr_t result;
- /* Safer if static, since otherwise it may not be */
- /* preserved across the longjmp. Can safely be */
- /* static since it's only called with the */
- /* allocation lock held. */
-
- GC_ASSERT(I_HOLD_LOCK());
- GC_setup_temporary_fault_handler();
- if (SETJMP(GC_jmp_buf) == 0) {
- result = (ptr_t)(((word)(p))
- & ~(MIN_PAGE_SIZE-1));
- for (;;) {
- if (up) {
- result += MIN_PAGE_SIZE;
- if (result >= bound) return bound;
- } else {
- result -= MIN_PAGE_SIZE;
- if (result <= bound) return bound;
- }
- GC_noop1((word)(*result));
- }
- }
- GC_reset_fault_handler();
- if (!up) {
- result += MIN_PAGE_SIZE;
- }
- return(result);
- }
-
- ptr_t GC_find_limit(ptr_t p, GC_bool up)
- {
- return GC_find_limit_with_bound(p, up, up ? (ptr_t)(word)(-1) : 0);
- }
-# endif
-
-#if defined(ECOS) || defined(NOSYS)
- ptr_t GC_get_main_stack_base(void)
- {
- return STACKBOTTOM;
- }
-#endif
-
-#ifdef HPUX_STACKBOTTOM
-
-#include <sys/param.h>
-#include <sys/pstat.h>
-
- GC_INNER ptr_t GC_get_register_stack_base(void)
- {
- struct pst_vm_status vm_status;
-
- int i = 0;
- while (pstat_getprocvm(&vm_status, sizeof(vm_status), 0, i++) == 1) {
- if (vm_status.pst_type == PS_RSESTACK) {
- return (ptr_t) vm_status.pst_vaddr;
- }
- }
-
- /* old way to get the register stackbottom */
- return (ptr_t)(((word)GC_stackbottom - BACKING_STORE_DISPLACEMENT - 1)
- & ~(BACKING_STORE_ALIGNMENT - 1));
- }
-
-#endif /* HPUX_STACK_BOTTOM */
-
-#ifdef LINUX_STACKBOTTOM
-
-#include <sys/types.h>
-#include <sys/stat.h>
-
-# define STAT_SKIP 27 /* Number of fields preceding startstack */
- /* field in /proc/self/stat */
-
-#ifdef USE_LIBC_PRIVATES
-# pragma weak __libc_stack_end
- extern ptr_t __libc_stack_end;
-#endif
-
-# ifdef IA64
-# ifdef USE_LIBC_PRIVATES
-# pragma weak __libc_ia64_register_backing_store_base
- extern ptr_t __libc_ia64_register_backing_store_base;
-# endif
-
- GC_INNER ptr_t GC_get_register_stack_base(void)
- {
- ptr_t result;
-
-# ifdef USE_LIBC_PRIVATES
- if (0 != &__libc_ia64_register_backing_store_base
- && 0 != __libc_ia64_register_backing_store_base) {
- /* Glibc 2.2.4 has a bug such that for dynamically linked */
- /* executables __libc_ia64_register_backing_store_base is */
- /* defined but uninitialized during constructor calls. */
- /* Hence we check for both nonzero address and value. */
- return __libc_ia64_register_backing_store_base;
- }
-# endif
- result = backing_store_base_from_proc();
- if (0 == result) {
- result = GC_find_limit(GC_save_regs_in_stack(), FALSE);
- /* Now seems to work better than constant displacement */
- /* heuristic used in 6.X versions. The latter seems to */
- /* fail for 2.6 kernels. */
- }
- return result;
- }
-# endif
-
- STATIC ptr_t GC_linux_stack_base(void)
- {
- /* We read the stack base value from /proc/self/stat. We do this */
- /* using direct I/O system calls in order to avoid calling malloc */
- /* in case REDIRECT_MALLOC is defined. */
-# ifndef STAT_READ
- /* Also defined in pthread_support.c. */
-# define STAT_BUF_SIZE 4096
-# define STAT_READ read
-# endif
- /* Should probably call the real read, if read is wrapped. */
- char stat_buf[STAT_BUF_SIZE];
- int f;
- char c;
- word result = 0;
- size_t i, buf_offset = 0;
-
- /* First try the easy way. This should work for glibc 2.2 */
- /* This fails in a prelinked ("prelink" command) executable */
- /* since the correct value of __libc_stack_end never */
- /* becomes visible to us. The second test works around */
- /* this. */
-# ifdef USE_LIBC_PRIVATES
- if (0 != &__libc_stack_end && 0 != __libc_stack_end ) {
-# if defined(IA64)
- /* Some versions of glibc set the address 16 bytes too */
- /* low while the initialization code is running. */
- if (((word)__libc_stack_end & 0xfff) + 0x10 < 0x1000) {
- return __libc_stack_end + 0x10;
- } /* Otherwise it's not safe to add 16 bytes and we fall */
- /* back to using /proc. */
-# elif defined(SPARC)
- /* Older versions of glibc for 64-bit Sparc do not set
- * this variable correctly, it gets set to either zero
- * or one.
- */
- if (__libc_stack_end != (ptr_t) (unsigned long)0x1)
- return __libc_stack_end;
-# else
- return __libc_stack_end;
-# endif
- }
-# endif
- f = open("/proc/self/stat", O_RDONLY);
- if (f < 0 || STAT_READ(f, stat_buf, STAT_BUF_SIZE) < 2 * STAT_SKIP) {
- ABORT("Couldn't read /proc/self/stat");
- }
- c = stat_buf[buf_offset++];
- /* Skip the required number of fields. This number is hopefully */
- /* constant across all Linux implementations. */
- for (i = 0; i < STAT_SKIP; ++i) {
- while (isspace(c)) c = stat_buf[buf_offset++];
- while (!isspace(c)) c = stat_buf[buf_offset++];
- }
- while (isspace(c)) c = stat_buf[buf_offset++];
- while (isdigit(c)) {
- result *= 10;
- result += c - '0';
- c = stat_buf[buf_offset++];
- }
- close(f);
- if (result < 0x100000) ABORT("Absurd stack bottom value");
- return (ptr_t)result;
- }
-
-#endif /* LINUX_STACKBOTTOM */
-
-#ifdef FREEBSD_STACKBOTTOM
-
-/* This uses an undocumented sysctl call, but at least one expert */
-/* believes it will stay. */
-
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/sysctl.h>
-
- STATIC ptr_t GC_freebsd_stack_base(void)
- {
- int nm[2] = {CTL_KERN, KERN_USRSTACK};
- ptr_t base;
- size_t len = sizeof(ptr_t);
- int r = sysctl(nm, 2, &base, &len, NULL, 0);
-
- if (r) ABORT("Error getting stack base");
-
- return base;
- }
-
-#endif /* FREEBSD_STACKBOTTOM */
-
-#if !defined(BEOS) && !defined(AMIGA) && !defined(MSWIN32) \
- && !defined(MSWINCE) && !defined(OS2) && !defined(NOSYS) && !defined(ECOS) \
- && !defined(CYGWIN32) && !defined(GC_OPENBSD_THREADS)
-
-ptr_t GC_get_main_stack_base(void)
-{
-# ifdef STACKBOTTOM
- return(STACKBOTTOM);
-# else
-# if defined(HEURISTIC1) || defined(HEURISTIC2)
- word dummy;
-# endif
- ptr_t result;
-# define STACKBOTTOM_ALIGNMENT_M1 ((word)STACK_GRAN - 1)
-# ifdef HEURISTIC1
-# ifdef STACK_GROWS_DOWN
- result = (ptr_t)((((word)(&dummy))
- + STACKBOTTOM_ALIGNMENT_M1)
- & ~STACKBOTTOM_ALIGNMENT_M1);
-# else
- result = (ptr_t)(((word)(&dummy))
- & ~STACKBOTTOM_ALIGNMENT_M1);
-# endif
-# endif /* HEURISTIC1 */
-# ifdef LINUX_STACKBOTTOM
- result = GC_linux_stack_base();
-# endif
-# ifdef FREEBSD_STACKBOTTOM
- result = GC_freebsd_stack_base();
-# endif
-# ifdef HEURISTIC2
-# ifdef STACK_GROWS_DOWN
- result = GC_find_limit((ptr_t)(&dummy), TRUE);
-# ifdef HEURISTIC2_LIMIT
- if (result > HEURISTIC2_LIMIT
- && (ptr_t)(&dummy) < HEURISTIC2_LIMIT) {
- result = HEURISTIC2_LIMIT;
- }
-# endif
-# else
- result = GC_find_limit((ptr_t)(&dummy), FALSE);
-# ifdef HEURISTIC2_LIMIT
- if (result < HEURISTIC2_LIMIT
- && (ptr_t)(&dummy) > HEURISTIC2_LIMIT) {
- result = HEURISTIC2_LIMIT;
- }
-# endif
-# endif
-
-# endif /* HEURISTIC2 */
-# ifdef STACK_GROWS_DOWN
- if (result == 0) result = (ptr_t)(signed_word)(-sizeof(ptr_t));
-# endif
- return(result);
-# endif /* STACKBOTTOM */
-}
-
-# endif /* ! AMIGA, !OS 2, ! MS Windows, !BEOS, !NOSYS, !ECOS */
-
-#if defined(GC_LINUX_THREADS) && !defined(HAVE_GET_STACK_BASE)
-
-#include <pthread.h>
-/* extern int pthread_getattr_np(pthread_t, pthread_attr_t *); */
-
-#ifdef IA64
- GC_INNER ptr_t GC_greatest_stack_base_below(ptr_t bound);
- /* From pthread_support.c */
-#endif
-
-GC_API int GC_CALL GC_get_stack_base(struct GC_stack_base *b)
-{
- pthread_attr_t attr;
- size_t size;
-
- if (pthread_getattr_np(pthread_self(), &attr) != 0) {
- WARN("pthread_getattr_np failed\n", 0);
- return GC_UNIMPLEMENTED;
- }
- if (pthread_attr_getstack(&attr, &(b -> mem_base), &size) != 0) {
- ABORT("pthread_attr_getstack failed");
- }
- pthread_attr_destroy(&attr);
-# ifdef STACK_GROWS_DOWN
- b -> mem_base = (char *)(b -> mem_base) + size;
-# endif
-# ifdef IA64
- /* We could try backing_store_base_from_proc, but that's safe */
- /* only if no mappings are being asynchronously created. */
- /* Subtracting the size from the stack base doesn't work for at */
- /* least the main thread. */
- LOCK();
- {
- IF_CANCEL(int cancel_state;)
- ptr_t bsp;
- ptr_t next_stack;
-
- DISABLE_CANCEL(cancel_state);
- bsp = GC_save_regs_in_stack();
- next_stack = GC_greatest_stack_base_below(bsp);
- if (0 == next_stack) {
- b -> reg_base = GC_find_limit(bsp, FALSE);
- } else {
- /* Avoid walking backwards into preceding memory stack and */
- /* growing it. */
- b -> reg_base = GC_find_limit_with_bound(bsp, FALSE, next_stack);
- }
- RESTORE_CANCEL(cancel_state);
- }
- UNLOCK();
-# endif
- return GC_SUCCESS;
-}
-
-# define HAVE_GET_STACK_BASE
-
-#endif /* GC_LINUX_THREADS */
-
-#ifdef GC_OPENBSD_THREADS
-
-# include <sys/signal.h>
-# include <pthread.h>
-# include <pthread_np.h>
-
- /* Find the stack using pthread_stackseg_np(). */
- GC_API int GC_CALL GC_get_stack_base(struct GC_stack_base *sb)
- {
- stack_t stack;
- pthread_stackseg_np(pthread_self(), &stack);
- sb->mem_base = stack.ss_sp;
- return GC_SUCCESS;
- }
-
-# define HAVE_GET_STACK_BASE
-
- /* This is always called from the main thread. */
- ptr_t GC_get_main_stack_base(void)
- {
- struct GC_stack_base sb;
- GC_get_stack_base(&sb);
- GC_ASSERT((void *)&sb HOTTER_THAN sb.mem_base);
- return (ptr_t)sb.mem_base;
- }
-
-#endif /* GC_OPENBSD_THREADS */
-
-#ifndef HAVE_GET_STACK_BASE
-/* Retrieve stack base. */
-/* Using the GC_find_limit version is risky. */
-/* On IA64, for example, there is no guard page between the */
-/* stack of one thread and the register backing store of the */
-/* next. Thus this is likely to identify way too large a */
-/* "stack" and thus at least result in disastrous performance. */
-/* FIXME - Implement better strategies here. */
-GC_API int GC_CALL GC_get_stack_base(struct GC_stack_base *b)
-{
-# ifdef NEED_FIND_LIMIT
- int dummy;
- IF_CANCEL(int cancel_state;)
- DISABLE_CANCEL(cancel_state); /* May be unnecessary? */
-# ifdef STACK_GROWS_DOWN
- b -> mem_base = GC_find_limit((ptr_t)(&dummy), TRUE);
-# ifdef IA64
- b -> reg_base = GC_find_limit(GC_save_regs_in_stack(), FALSE);
-# endif
-# else
- b -> mem_base = GC_find_limit(&dummy, FALSE);
-# endif
- RESTORE_CANCEL(cancel_state);
- return GC_SUCCESS;
-# else
- return GC_UNIMPLEMENTED;
-# endif
-}
-#endif
-
-/*
- * Register static data segment(s) as roots.
- * If more data segments are added later then they need to be registered
- * add that point (as we do with SunOS dynamic loading),
- * or GC_mark_roots needs to check for them (as we do with PCR).
- * Called with allocator lock held.
- */
-
-# ifdef OS2
-
-void GC_register_data_segments(void)
-{
- PTIB ptib;
- PPIB ppib;
- HMODULE module_handle;
-# define PBUFSIZ 512
- UCHAR path[PBUFSIZ];
- FILE * myexefile;
- struct exe_hdr hdrdos; /* MSDOS header. */
- struct e32_exe hdr386; /* Real header for my executable */
- struct o32_obj seg; /* Currrent segment */
- int nsegs;
-
-
- if (DosGetInfoBlocks(&ptib, &ppib) != NO_ERROR) {
- GC_err_printf("DosGetInfoBlocks failed\n");
- ABORT("DosGetInfoBlocks failed\n");
- }
- module_handle = ppib -> pib_hmte;
- if (DosQueryModuleName(module_handle, PBUFSIZ, path) != NO_ERROR) {
- GC_err_printf("DosQueryModuleName failed\n");
- ABORT("DosGetInfoBlocks failed\n");
- }
- myexefile = fopen(path, "rb");
- if (myexefile == 0) {
- GC_err_puts("Couldn't open executable ");
- GC_err_puts(path); GC_err_puts("\n");
- ABORT("Failed to open executable\n");
- }
- if (fread((char *)(&hdrdos), 1, sizeof hdrdos, myexefile) < sizeof hdrdos) {
- GC_err_puts("Couldn't read MSDOS header from ");
- GC_err_puts(path); GC_err_puts("\n");
- ABORT("Couldn't read MSDOS header");
- }
- if (E_MAGIC(hdrdos) != EMAGIC) {
- GC_err_puts("Executable has wrong DOS magic number: ");
- GC_err_puts(path); GC_err_puts("\n");
- ABORT("Bad DOS magic number");
- }
- if (fseek(myexefile, E_LFANEW(hdrdos), SEEK_SET) != 0) {
- GC_err_puts("Seek to new header failed in ");
- GC_err_puts(path); GC_err_puts("\n");
- ABORT("Bad DOS magic number");
- }
- if (fread((char *)(&hdr386), 1, sizeof hdr386, myexefile) < sizeof hdr386) {
- GC_err_puts("Couldn't read MSDOS header from ");
- GC_err_puts(path); GC_err_puts("\n");
- ABORT("Couldn't read OS/2 header");
- }
- if (E32_MAGIC1(hdr386) != E32MAGIC1 || E32_MAGIC2(hdr386) != E32MAGIC2) {
- GC_err_puts("Executable has wrong OS/2 magic number:");
- GC_err_puts(path); GC_err_puts("\n");
- ABORT("Bad OS/2 magic number");
- }
- if ( E32_BORDER(hdr386) != E32LEBO || E32_WORDER(hdr386) != E32LEWO) {
- GC_err_puts("Executable %s has wrong byte order: ");
- GC_err_puts(path); GC_err_puts("\n");
- ABORT("Bad byte order");
- }
- if ( E32_CPU(hdr386) == E32CPU286) {
- GC_err_puts("GC can't handle 80286 executables: ");
- GC_err_puts(path); GC_err_puts("\n");
- EXIT();
- }
- if (fseek(myexefile, E_LFANEW(hdrdos) + E32_OBJTAB(hdr386),
- SEEK_SET) != 0) {
- GC_err_puts("Seek to object table failed: ");
- GC_err_puts(path); GC_err_puts("\n");
- ABORT("Seek to object table failed");
- }
- for (nsegs = E32_OBJCNT(hdr386); nsegs > 0; nsegs--) {
- int flags;
- if (fread((char *)(&seg), 1, sizeof seg, myexefile) < sizeof seg) {
- GC_err_puts("Couldn't read obj table entry from ");
- GC_err_puts(path); GC_err_puts("\n");
- ABORT("Couldn't read obj table entry");
- }
- flags = O32_FLAGS(seg);
- if (!(flags & OBJWRITE)) continue;
- if (!(flags & OBJREAD)) continue;
- if (flags & OBJINVALID) {
- GC_err_printf("Object with invalid pages?\n");
- continue;
- }
- GC_add_roots_inner((ptr_t)O32_BASE(seg),
- (ptr_t)(O32_BASE(seg)+O32_SIZE(seg)), FALSE);
- }
-}
-
-# else /* !OS2 */
-
-# if defined(GWW_VDB)
-
-# ifndef MEM_WRITE_WATCH
-# define MEM_WRITE_WATCH 0x200000
-# endif
-
-# ifndef WRITE_WATCH_FLAG_RESET
-# define WRITE_WATCH_FLAG_RESET 1
-# endif
-
- /* Since we can't easily check whether ULONG_PTR and SIZE_T are */
- /* defined in Win32 basetsd.h, we define own ULONG_PTR. */
-# define GC_ULONG_PTR word
-
- typedef UINT (WINAPI * GetWriteWatch_type)(
- DWORD, PVOID, GC_ULONG_PTR /* SIZE_T */,
- PVOID *, GC_ULONG_PTR *, PULONG);
- static GetWriteWatch_type GetWriteWatch_func;
- static DWORD GetWriteWatch_alloc_flag;
-
-# define GC_GWW_AVAILABLE() (GetWriteWatch_func != NULL)
-
- static void detect_GetWriteWatch(void)
- {
- static GC_bool done;
- HMODULE hK32;
- if (done)
- return;
-
-# if defined(MPROTECT_VDB)
- {
- char * str = GETENV("GC_USE_GETWRITEWATCH");
-# if defined(GC_PREFER_MPROTECT_VDB)
- if (str == NULL || (*str == '0' && *(str + 1) == '\0')) {
- /* GC_USE_GETWRITEWATCH is unset or set to "0". */
- done = TRUE; /* falling back to MPROTECT_VDB strategy. */
- /* This should work as if GWW_VDB is undefined. */
- return;
- }
-# else
- if (str != NULL && *str == '0' && *(str + 1) == '\0') {
- /* GC_USE_GETWRITEWATCH is set "0". */
- done = TRUE; /* falling back to MPROTECT_VDB strategy. */
- return;
- }
-# endif
- }
-# endif
-
- hK32 = GetModuleHandle(TEXT("kernel32.dll"));
- if (hK32 != (HMODULE)0 &&
- (GetWriteWatch_func = (GetWriteWatch_type)GetProcAddress(hK32,
- "GetWriteWatch")) != NULL) {
- /* Also check whether VirtualAlloc accepts MEM_WRITE_WATCH, */
- /* as some versions of kernel32.dll have one but not the */
- /* other, making the feature completely broken. */
- void * page = VirtualAlloc(NULL, GC_page_size,
- MEM_WRITE_WATCH | MEM_RESERVE,
- PAGE_READWRITE);
- if (page != NULL) {
- PVOID pages[16];
- GC_ULONG_PTR count = 16;
- DWORD page_size;
- /* Check that it actually works. In spite of some */
- /* documentation it actually seems to exist on W2K. */
- /* This test may be unnecessary, but ... */
- if (GetWriteWatch_func(WRITE_WATCH_FLAG_RESET,
- page, GC_page_size,
- pages,
- &count,
- &page_size) != 0) {
- /* GetWriteWatch always fails. */
- GetWriteWatch_func = NULL;
- } else {
- GetWriteWatch_alloc_flag = MEM_WRITE_WATCH;
- }
- VirtualFree(page, GC_page_size, MEM_RELEASE);
- } else {
- /* GetWriteWatch will be useless. */
- GetWriteWatch_func = NULL;
- }
- }
- if (GC_print_stats) {
- if (GetWriteWatch_func == NULL) {
- GC_log_printf("Did not find a usable GetWriteWatch()\n");
- } else {
- GC_log_printf("Using GetWriteWatch()\n");
- }
- }
- done = TRUE;
- }
-
-# else /* !GWW_VDB */
-# define GetWriteWatch_alloc_flag 0
-# endif /* GWW_VDB */
-
-# if defined(MSWIN32) || defined(MSWINCE)
-
-# ifdef MSWIN32
- /* Unfortunately, we have to handle win32s very differently from NT, */
- /* Since VirtualQuery has very different semantics. In particular, */
- /* under win32s a VirtualQuery call on an unmapped page returns an */
- /* invalid result. Under NT, GC_register_data_segments is a no-op */
- /* and all real work is done by GC_register_dynamic_libraries. Under */
- /* win32s, we cannot find the data segments associated with dll's. */
- /* We register the main data segment here. */
- GC_INNER GC_bool GC_no_win32_dlls = FALSE;
- /* This used to be set for gcc, to avoid dealing with */
- /* the structured exception handling issues. But we now have */
- /* assembly code to do that right. */
-
- GC_INNER GC_bool GC_wnt = FALSE;
- /* This is a Windows NT derivative, i.e. NT, W2K, XP or later. */
-
- GC_INNER void GC_init_win32(void)
- {
- /* Set GC_wnt. If we're running under win32s, assume that no DLLs */
- /* will be loaded. I doubt anyone still runs win32s, but... */
- DWORD v = GetVersion();
- GC_wnt = !(v & 0x80000000);
- GC_no_win32_dlls |= ((!GC_wnt) && (v & 0xff) <= 3);
-# ifdef USE_MUNMAP
- if (GC_no_win32_dlls) {
- /* Turn off unmapping for safety (since may not work well with */
- /* GlobalAlloc). */
- GC_unmap_threshold = 0;
- }
-# endif
- }
-
- /* Return the smallest address a such that VirtualQuery */
- /* returns correct results for all addresses between a and start. */
- /* Assumes VirtualQuery returns correct information for start. */
- STATIC ptr_t GC_least_described_address(ptr_t start)
- {
- MEMORY_BASIC_INFORMATION buf;
- size_t result;
- LPVOID limit;
- ptr_t p;
- LPVOID q;
-
- limit = GC_sysinfo.lpMinimumApplicationAddress;
- p = (ptr_t)((word)start & ~(GC_page_size - 1));
- for (;;) {
- q = (LPVOID)(p - GC_page_size);
- if ((ptr_t)q > (ptr_t)p /* underflow */ || q < limit) break;
- result = VirtualQuery(q, &buf, sizeof(buf));
- if (result != sizeof(buf) || buf.AllocationBase == 0) break;
- p = (ptr_t)(buf.AllocationBase);
- }
- return p;
- }
-# endif
-
-# ifndef REDIRECT_MALLOC
- /* We maintain a linked list of AllocationBase values that we know */
- /* correspond to malloc heap sections. Currently this is only called */
- /* during a GC. But there is some hope that for long running */
- /* programs we will eventually see most heap sections. */
-
- /* In the long run, it would be more reliable to occasionally walk */
- /* the malloc heap with HeapWalk on the default heap. But that */
- /* apparently works only for NT-based Windows. */
-
- /* In the long run, a better data structure would also be nice ... */
- STATIC struct GC_malloc_heap_list {
- void * allocation_base;
- struct GC_malloc_heap_list *next;
- } *GC_malloc_heap_l = 0;
-
- /* Is p the base of one of the malloc heap sections we already know */
- /* about? */
- STATIC GC_bool GC_is_malloc_heap_base(ptr_t p)
- {
- struct GC_malloc_heap_list *q = GC_malloc_heap_l;
-
- while (0 != q) {
- if (q -> allocation_base == p) return TRUE;
- q = q -> next;
- }
- return FALSE;
- }
-
- STATIC void *GC_get_allocation_base(void *p)
- {
- MEMORY_BASIC_INFORMATION buf;
- size_t result = VirtualQuery(p, &buf, sizeof(buf));
- if (result != sizeof(buf)) {
- ABORT("Weird VirtualQuery result");
- }
- return buf.AllocationBase;
- }
-
- STATIC size_t GC_max_root_size = 100000; /* Appr. largest root size. */
-
- GC_INNER void GC_add_current_malloc_heap(void)
- {
- struct GC_malloc_heap_list *new_l =
- malloc(sizeof(struct GC_malloc_heap_list));
- void * candidate = GC_get_allocation_base(new_l);
-
- if (new_l == 0) return;
- if (GC_is_malloc_heap_base(candidate)) {
- /* Try a little harder to find malloc heap. */
- size_t req_size = 10000;
- do {
- void *p = malloc(req_size);
- if (0 == p) { free(new_l); return; }
- candidate = GC_get_allocation_base(p);
- free(p);
- req_size *= 2;
- } while (GC_is_malloc_heap_base(candidate)
- && req_size < GC_max_root_size/10 && req_size < 500000);
- if (GC_is_malloc_heap_base(candidate)) {
- free(new_l); return;
- }
- }
- if (GC_print_stats)
- GC_log_printf("Found new system malloc AllocationBase at %p\n",
- candidate);
- new_l -> allocation_base = candidate;
- new_l -> next = GC_malloc_heap_l;
- GC_malloc_heap_l = new_l;
- }
-# endif /* REDIRECT_MALLOC */
-
- STATIC word GC_n_heap_bases = 0; /* See GC_heap_bases. */
-
- /* Is p the start of either the malloc heap, or of one of our */
- /* heap sections? */
- GC_INNER GC_bool GC_is_heap_base(ptr_t p)
- {
- unsigned i;
-# ifndef REDIRECT_MALLOC
- if (GC_root_size > GC_max_root_size) GC_max_root_size = GC_root_size;
- if (GC_is_malloc_heap_base(p)) return TRUE;
-# endif
- for (i = 0; i < GC_n_heap_bases; i++) {
- if (GC_heap_bases[i] == p) return TRUE;
- }
- return FALSE;
- }
-
-# ifdef MSWIN32
- STATIC void GC_register_root_section(ptr_t static_root)
- {
- MEMORY_BASIC_INFORMATION buf;
- size_t result;
- DWORD protect;
- LPVOID p;
- char * base;
- char * limit, * new_limit;
-
- if (!GC_no_win32_dlls) return;
- p = base = limit = GC_least_described_address(static_root);
- while (p < GC_sysinfo.lpMaximumApplicationAddress) {
- result = VirtualQuery(p, &buf, sizeof(buf));
- if (result != sizeof(buf) || buf.AllocationBase == 0
- || GC_is_heap_base(buf.AllocationBase)) break;
- new_limit = (char *)p + buf.RegionSize;
- protect = buf.Protect;
- if (buf.State == MEM_COMMIT
- && is_writable(protect)) {
- if ((char *)p == limit) {
- limit = new_limit;
- } else {
- if (base != limit) GC_add_roots_inner(base, limit, FALSE);
- base = p;
- limit = new_limit;
- }
- }
- if (p > (LPVOID)new_limit /* overflow */) break;
- p = (LPVOID)new_limit;
- }
- if (base != limit) GC_add_roots_inner(base, limit, FALSE);
- }
-#endif
-
- void GC_register_data_segments(void)
- {
-# ifdef MSWIN32
- static char dummy;
- GC_register_root_section((ptr_t)(&dummy));
-# endif
- }
-
-# else /* !OS2 && !Windows */
-
-# if (defined(SVR4) || defined(AUX) || defined(DGUX) \
- || (defined(LINUX) && defined(SPARC))) && !defined(PCR)
-ptr_t GC_SysVGetDataStart(size_t max_page_size, ptr_t etext_addr)
-{
- word text_end = ((word)(etext_addr) + sizeof(word) - 1)
- & ~(sizeof(word) - 1);
- /* etext rounded to word boundary */
- word next_page = ((text_end + (word)max_page_size - 1)
- & ~((word)max_page_size - 1));
- word page_offset = (text_end & ((word)max_page_size - 1));
- volatile char * result = (char *)(next_page + page_offset);
- /* Note that this isnt equivalent to just adding */
- /* max_page_size to &etext if &etext is at a page boundary */
-
- GC_setup_temporary_fault_handler();
- if (SETJMP(GC_jmp_buf) == 0) {
- /* Try writing to the address. */
- *result = *result;
- GC_reset_fault_handler();
- } else {
- GC_reset_fault_handler();
- /* We got here via a longjmp. The address is not readable. */
- /* This is known to happen under Solaris 2.4 + gcc, which place */
- /* string constants in the text segment, but after etext. */
- /* Use plan B. Note that we now know there is a gap between */
- /* text and data segments, so plan A bought us something. */
- result = (char *)GC_find_limit((ptr_t)(DATAEND), FALSE);
- }
- return((ptr_t)result);
-}
-# endif
-
-# if defined(FREEBSD) && !defined(PCR) && (defined(I386) || defined(X86_64) \
- || defined(powerpc) || defined(__powerpc__))
-
-/* Its unclear whether this should be identical to the above, or */
-/* whether it should apply to non-X86 architectures. */
-/* For now we don't assume that there is always an empty page after */
-/* etext. But in some cases there actually seems to be slightly more. */
-/* This also deals with holes between read-only data and writable data. */
-ptr_t GC_FreeBSDGetDataStart(size_t max_page_size, ptr_t etext_addr)
-{
- word text_end = ((word)(etext_addr) + sizeof(word) - 1)
- & ~(sizeof(word) - 1);
- /* etext rounded to word boundary */
- volatile word next_page = (text_end + (word)max_page_size - 1)
- & ~((word)max_page_size - 1);
- volatile ptr_t result = (ptr_t)text_end;
- GC_setup_temporary_fault_handler();
- if (SETJMP(GC_jmp_buf) == 0) {
- /* Try reading at the address. */
- /* This should happen before there is another thread. */
- for (; next_page < (word)(DATAEND); next_page += (word)max_page_size)
- *(volatile char *)next_page;
- GC_reset_fault_handler();
- } else {
- GC_reset_fault_handler();
- /* As above, we go to plan B */
- result = GC_find_limit((ptr_t)(DATAEND), FALSE);
- }
- return(result);
-}
-
-# endif /* FREEBSD */
-
-
-#ifdef AMIGA
-
-# define GC_AMIGA_DS
-# include "extra/AmigaOS.c"
-# undef GC_AMIGA_DS
-
-#elif defined(OPENBSD)
-
-/* Depending on arch alignment, there can be multiple holes */
-/* between DATASTART and DATAEND. Scan in DATASTART .. DATAEND */
-/* and register each region. */
-void GC_register_data_segments(void)
-{
- ptr_t region_start = DATASTART;
- ptr_t region_end;
-
- for (;;) {
- region_end = GC_find_limit_openbsd(region_start, DATAEND);
- GC_add_roots_inner(region_start, region_end, FALSE);
- if (region_end >= DATAEND)
- break;
- region_start = GC_skip_hole_openbsd(region_end, DATAEND);
- }
-}
-
-# else /* !OS2 && !Windows && !AMIGA && !OPENBSD */
-
-void GC_register_data_segments(void)
-{
-# if !defined(PCR) && !defined(MACOS)
-# if defined(REDIRECT_MALLOC) && defined(GC_SOLARIS_THREADS)
- /* As of Solaris 2.3, the Solaris threads implementation */
- /* allocates the data structure for the initial thread with */
- /* sbrk at process startup. It needs to be scanned, so that */
- /* we don't lose some malloc allocated data structures */
- /* hanging from it. We're on thin ice here ... */
- extern caddr_t sbrk(int);
-
- GC_add_roots_inner(DATASTART, (ptr_t)sbrk(0), FALSE);
-# else
- GC_add_roots_inner(DATASTART, (ptr_t)(DATAEND), FALSE);
-# if defined(DATASTART2)
- GC_add_roots_inner(DATASTART2, (ptr_t)(DATAEND2), FALSE);
-# endif
-# endif
-# endif
-# if defined(MACOS)
- {
-# if defined(THINK_C)
- extern void* GC_MacGetDataStart(void);
- /* globals begin above stack and end at a5. */
- GC_add_roots_inner((ptr_t)GC_MacGetDataStart(),
- (ptr_t)LMGetCurrentA5(), FALSE);
-# else
-# if defined(__MWERKS__)
-# if !__POWERPC__
- extern void* GC_MacGetDataStart(void);
- /* MATTHEW: Function to handle Far Globals (CW Pro 3) */
-# if __option(far_data)
- extern void* GC_MacGetDataEnd(void);
-# endif
- /* globals begin above stack and end at a5. */
- GC_add_roots_inner((ptr_t)GC_MacGetDataStart(),
- (ptr_t)LMGetCurrentA5(), FALSE);
- /* MATTHEW: Handle Far Globals */
-# if __option(far_data)
- /* Far globals follow he QD globals: */
- GC_add_roots_inner((ptr_t)LMGetCurrentA5(),
- (ptr_t)GC_MacGetDataEnd(), FALSE);
-# endif
-# else
- extern char __data_start__[], __data_end__[];
- GC_add_roots_inner((ptr_t)&__data_start__,
- (ptr_t)&__data_end__, FALSE);
-# endif /* __POWERPC__ */
-# endif /* __MWERKS__ */
-# endif /* !THINK_C */
- }
-# endif /* MACOS */
-
- /* Dynamic libraries are added at every collection, since they may */
- /* change. */
-}
-
-# endif /* ! AMIGA */
-# endif /* ! MSWIN32 && ! MSWINCE*/
-# endif /* ! OS2 */
-
-/*
- * Auxiliary routines for obtaining memory from OS.
- */
-
-# if !defined(OS2) && !defined(PCR) && !defined(AMIGA) \
- && !defined(MSWIN32) && !defined(MSWINCE) \
- && !defined(MACOS) && !defined(DOS4GW) && !defined(NONSTOP)
-
-# define SBRK_ARG_T ptrdiff_t
-
-#if defined(MMAP_SUPPORTED)
-
-#ifdef USE_MMAP_FIXED
-# define GC_MMAP_FLAGS MAP_FIXED | MAP_PRIVATE
- /* Seems to yield better performance on Solaris 2, but can */
- /* be unreliable if something is already mapped at the address. */
-#else
-# define GC_MMAP_FLAGS MAP_PRIVATE
-#endif
-
-#ifdef USE_MMAP_ANON
-# define zero_fd -1
-# if defined(MAP_ANONYMOUS)
-# define OPT_MAP_ANON MAP_ANONYMOUS
-# else
-# define OPT_MAP_ANON MAP_ANON
-# endif
-#else
- static int zero_fd;
-# define OPT_MAP_ANON 0
-#endif
-
-#ifndef HEAP_START
-# define HEAP_START ((ptr_t)0)
-#endif
-
-STATIC ptr_t GC_unix_mmap_get_mem(word bytes)
-{
- void *result;
- static ptr_t last_addr = HEAP_START;
-
-# ifndef USE_MMAP_ANON
- static GC_bool initialized = FALSE;
-
- if (!initialized) {
- zero_fd = open("/dev/zero", O_RDONLY);
- fcntl(zero_fd, F_SETFD, FD_CLOEXEC);
- initialized = TRUE;
- }
-# endif
-
- if (bytes & (GC_page_size - 1)) ABORT("Bad GET_MEM arg");
- result = mmap(last_addr, bytes, PROT_READ | PROT_WRITE | OPT_PROT_EXEC,
- GC_MMAP_FLAGS | OPT_MAP_ANON, zero_fd, 0/* offset */);
- if (result == MAP_FAILED) return(0);
- last_addr = (ptr_t)result + bytes + GC_page_size - 1;
- last_addr = (ptr_t)((word)last_addr & ~(GC_page_size - 1));
-# if !defined(LINUX)
- if (last_addr == 0) {
- /* Oops. We got the end of the address space. This isn't */
- /* usable by arbitrary C code, since one-past-end pointers */
- /* don't work, so we discard it and try again. */
- munmap(result, (size_t)(-GC_page_size) - (size_t)result);
- /* Leave last page mapped, so we can't repeat. */
- return GC_unix_mmap_get_mem(bytes);
- }
-# else
- GC_ASSERT(last_addr != 0);
-# endif
- return((ptr_t)result);
-}
-
-# endif /* MMAP_SUPPORTED */
-
-#if defined(USE_MMAP)
-
-ptr_t GC_unix_get_mem(word bytes)
-{
- return GC_unix_mmap_get_mem(bytes);
-}
-
-#else /* Not USE_MMAP */
-
-STATIC ptr_t GC_unix_sbrk_get_mem(word bytes)
-{
- ptr_t result;
-# ifdef IRIX5
- /* Bare sbrk isn't thread safe. Play by malloc rules. */
- /* The equivalent may be needed on other systems as well. */
- __LOCK_MALLOC();
-# endif
- {
- ptr_t cur_brk = (ptr_t)sbrk(0);
- SBRK_ARG_T lsbs = (word)cur_brk & (GC_page_size-1);
-
- if ((SBRK_ARG_T)bytes < 0) {
- result = 0; /* too big */
- goto out;
- }
- if (lsbs != 0) {
- if((ptr_t)sbrk(GC_page_size - lsbs) == (ptr_t)(-1)) {
- result = 0;
- goto out;
- }
- }
-# ifdef ADD_HEAP_GUARD_PAGES
- /* This is useful for catching severe memory overwrite problems that */
- /* span heap sections. It shouldn't otherwise be turned on. */
- {
- ptr_t guard = (ptr_t)sbrk((SBRK_ARG_T)GC_page_size);
- if (mprotect(guard, GC_page_size, PROT_NONE) != 0)
- ABORT("ADD_HEAP_GUARD_PAGES: mprotect failed");
- }
-# endif /* ADD_HEAP_GUARD_PAGES */
- result = (ptr_t)sbrk((SBRK_ARG_T)bytes);
- if (result == (ptr_t)(-1)) result = 0;
- }
- out:
-# ifdef IRIX5
- __UNLOCK_MALLOC();
-# endif
- return(result);
-}
-
-#if defined(MMAP_SUPPORTED)
- /* By default, we try both sbrk and mmap, in that order. */
- ptr_t GC_unix_get_mem(word bytes)
- {
- static GC_bool sbrk_failed = FALSE;
- ptr_t result = 0;
-
- if (!sbrk_failed) result = GC_unix_sbrk_get_mem(bytes);
- if (0 == result) {
- sbrk_failed = TRUE;
- result = GC_unix_mmap_get_mem(bytes);
- }
- if (0 == result) {
- /* Try sbrk again, in case sbrk memory became available. */
- result = GC_unix_sbrk_get_mem(bytes);
- }
- return result;
- }
-#else /* !MMAP_SUPPORTED */
- ptr_t GC_unix_get_mem(word bytes)
- {
- return GC_unix_sbrk_get_mem(bytes);
- }
-#endif
-
-#endif /* Not USE_MMAP */
-
-# endif /* UN*X */
-
-# ifdef OS2
-
-void * os2_alloc(size_t bytes)
-{
- void * result;
-
- if (DosAllocMem(&result, bytes, PAG_EXECUTE | PAG_READ |
- PAG_WRITE | PAG_COMMIT)
- != NO_ERROR) {
- return(0);
- }
- if (result == 0) return(os2_alloc(bytes));
- return(result);
-}
-
-# endif /* OS2 */
-
-
-# if defined(MSWIN32) || defined(MSWINCE)
- GC_INNER SYSTEM_INFO GC_sysinfo;
-# endif
-
-# ifdef MSWIN32
-
-# ifdef USE_GLOBAL_ALLOC
-# define GLOBAL_ALLOC_TEST 1
-# else
-# define GLOBAL_ALLOC_TEST GC_no_win32_dlls
-# endif
-
-#ifdef GC_USE_MEM_TOP_DOWN
- STATIC DWORD GC_mem_top_down = MEM_TOP_DOWN;
- /* Use GC_USE_MEM_TOP_DOWN for better 64-bit */
- /* testing. Otherwise all addresses tend to */
- /* end up in first 4GB, hiding bugs. */
-#else
- STATIC DWORD GC_mem_top_down = 0;
-#endif
-
-ptr_t GC_win32_get_mem(word bytes)
-{
- ptr_t result;
-
- if (GLOBAL_ALLOC_TEST) {
- /* VirtualAlloc doesn't like PAGE_EXECUTE_READWRITE. */
- /* There are also unconfirmed rumors of other */
- /* problems, so we dodge the issue. */
- result = (ptr_t) GlobalAlloc(0, bytes + HBLKSIZE);
- result = (ptr_t)(((word)result + HBLKSIZE - 1) & ~(HBLKSIZE-1));
- } else {
- /* VirtualProtect only works on regions returned by a */
- /* single VirtualAlloc call. Thus we allocate one */
- /* extra page, which will prevent merging of blocks */
- /* in separate regions, and eliminate any temptation */
- /* to call VirtualProtect on a range spanning regions. */
- /* This wastes a small amount of memory, and risks */
- /* increased fragmentation. But better alternatives */
- /* would require effort. */
-# ifdef MPROTECT_VDB
- /* We can't check for GC_incremental here (because */
- /* GC_enable_incremental() might be called some time */
- /* later after the GC initialization). */
-# ifdef GWW_VDB
-# define VIRTUAL_ALLOC_PAD (GC_GWW_AVAILABLE() ? 0 : 1)
-# else
-# define VIRTUAL_ALLOC_PAD 1
-# endif
-# else
-# define VIRTUAL_ALLOC_PAD 0
-# endif
- /* Pass the MEM_WRITE_WATCH only if GetWriteWatch-based */
- /* VDBs are enabled and the GetWriteWatch function is */
- /* available. Otherwise we waste resources or possibly */
- /* cause VirtualAlloc to fail (observed in Windows 2000 */
- /* SP2). */
- result = (ptr_t) VirtualAlloc(NULL, bytes + VIRTUAL_ALLOC_PAD,
- GetWriteWatch_alloc_flag |
- MEM_COMMIT | MEM_RESERVE
- | GC_mem_top_down,
- PAGE_EXECUTE_READWRITE);
- }
- if (HBLKDISPL(result) != 0) ABORT("Bad VirtualAlloc result");
- /* If I read the documentation correctly, this can */
- /* only happen if HBLKSIZE > 64k or not a power of 2. */
- if (GC_n_heap_bases >= MAX_HEAP_SECTS) ABORT("Too many heap sections");
- if (0 != result) GC_heap_bases[GC_n_heap_bases++] = result;
- return(result);
-}
-
-GC_API void GC_CALL GC_win32_free_heap(void)
-{
- if (GC_no_win32_dlls) {
- while (GC_n_heap_bases > 0) {
- GlobalFree (GC_heap_bases[--GC_n_heap_bases]);
- GC_heap_bases[GC_n_heap_bases] = 0;
- }
- }
-}
-# endif
-
-#ifdef AMIGA
-# define GC_AMIGA_AM
-# include "extra/AmigaOS.c"
-# undef GC_AMIGA_AM
-#endif
-
-
-#ifdef MSWINCE
- ptr_t GC_wince_get_mem(word bytes)
- {
- ptr_t result = 0; /* initialized to prevent warning. */
- word i;
-
- /* Round up allocation size to multiple of page size */
- bytes = (bytes + GC_page_size-1) & ~(GC_page_size-1);
-
- /* Try to find reserved, uncommitted pages */
- for (i = 0; i < GC_n_heap_bases; i++) {
- if (((word)(-(signed_word)GC_heap_lengths[i])
- & (GC_sysinfo.dwAllocationGranularity-1))
- >= bytes) {
- result = GC_heap_bases[i] + GC_heap_lengths[i];
- break;
- }
- }
-
- if (i == GC_n_heap_bases) {
- /* Reserve more pages */
- word res_bytes = (bytes + GC_sysinfo.dwAllocationGranularity-1)
- & ~(GC_sysinfo.dwAllocationGranularity-1);
- /* If we ever support MPROTECT_VDB here, we will probably need to */
- /* ensure that res_bytes is strictly > bytes, so that VirtualProtect */
- /* never spans regions. It seems to be OK for a VirtualFree */
- /* argument to span regions, so we should be OK for now. */
- result = (ptr_t) VirtualAlloc(NULL, res_bytes,
- MEM_RESERVE | MEM_TOP_DOWN,
- PAGE_EXECUTE_READWRITE);
- if (HBLKDISPL(result) != 0) ABORT("Bad VirtualAlloc result");
- /* If I read the documentation correctly, this can */
- /* only happen if HBLKSIZE > 64k or not a power of 2. */
- if (GC_n_heap_bases >= MAX_HEAP_SECTS) ABORT("Too many heap sections");
- if (result == NULL) return NULL;
- GC_heap_bases[GC_n_heap_bases] = result;
- GC_heap_lengths[GC_n_heap_bases] = 0;
- GC_n_heap_bases++;
- }
-
- /* Commit pages */
- result = (ptr_t) VirtualAlloc(result, bytes,
- MEM_COMMIT,
- PAGE_EXECUTE_READWRITE);
- if (result != NULL) {
- if (HBLKDISPL(result) != 0) ABORT("Bad VirtualAlloc result");
- GC_heap_lengths[i] += bytes;
- }
-
- return(result);
- }
-#endif
-
-#ifdef USE_MUNMAP
-
-/* For now, this only works on Win32/WinCE and some Unix-like */
-/* systems. If you have something else, don't define */
-/* USE_MUNMAP. */
-
-#if !defined(MSWIN32) && !defined(MSWINCE)
-
-#include <unistd.h>
-#include <sys/mman.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-
-#endif
-
-/* Compute a page aligned starting address for the unmap */
-/* operation on a block of size bytes starting at start. */
-/* Return 0 if the block is too small to make this feasible. */
-STATIC ptr_t GC_unmap_start(ptr_t start, size_t bytes)
-{
- ptr_t result;
- /* Round start to next page boundary. */
- result = (ptr_t)((word)(start + GC_page_size - 1) & ~(GC_page_size - 1));
- if (result + GC_page_size > start + bytes) return 0;
- return result;
-}
-
-/* Compute end address for an unmap operation on the indicated */
-/* block. */
-STATIC ptr_t GC_unmap_end(ptr_t start, size_t bytes)
-{
- return (ptr_t)((word)(start + bytes) & ~(GC_page_size - 1));
-}
-
-/* Under Win32/WinCE we commit (map) and decommit (unmap) */
-/* memory using VirtualAlloc and VirtualFree. These functions */
-/* work on individual allocations of virtual memory, made */
-/* previously using VirtualAlloc with the MEM_RESERVE flag. */
-/* The ranges we need to (de)commit may span several of these */
-/* allocations; therefore we use VirtualQuery to check */
-/* allocation lengths, and split up the range as necessary. */
-
-/* We assume that GC_remap is called on exactly the same range */
-/* as a previous call to GC_unmap. It is safe to consistently */
-/* round the endpoints in both places. */
-GC_INNER void GC_unmap(ptr_t start, size_t bytes)
-{
- ptr_t start_addr = GC_unmap_start(start, bytes);
- ptr_t end_addr = GC_unmap_end(start, bytes);
- word len = end_addr - start_addr;
- if (0 == start_addr) return;
-# if defined(MSWIN32) || defined(MSWINCE)
- while (len != 0) {
- MEMORY_BASIC_INFORMATION mem_info;
- GC_word free_len;
- if (VirtualQuery(start_addr, &mem_info, sizeof(mem_info))
- != sizeof(mem_info))
- ABORT("Weird VirtualQuery result");
- free_len = (len < mem_info.RegionSize) ? len : mem_info.RegionSize;
- if (!VirtualFree(start_addr, free_len, MEM_DECOMMIT))
- ABORT("VirtualFree failed");
- GC_unmapped_bytes += free_len;
- start_addr += free_len;
- len -= free_len;
- }
-# else
- /* We immediately remap it to prevent an intervening mmap from */
- /* accidentally grabbing the same address space. */
- {
- void * result;
- result = mmap(start_addr, len, PROT_NONE,
- MAP_PRIVATE | MAP_FIXED | OPT_MAP_ANON,
- zero_fd, 0/* offset */);
- if (result != (void *)start_addr) ABORT("mmap(...PROT_NONE...) failed");
- }
- GC_unmapped_bytes += len;
-# endif
-}
-
-GC_INNER void GC_remap(ptr_t start, size_t bytes)
-{
- ptr_t start_addr = GC_unmap_start(start, bytes);
- ptr_t end_addr = GC_unmap_end(start, bytes);
- word len = end_addr - start_addr;
-
- /* FIXME: Handle out-of-memory correctly (at least for Win32) */
-# if defined(MSWIN32) || defined(MSWINCE)
- ptr_t result;
-
- if (0 == start_addr) return;
- while (len != 0) {
- MEMORY_BASIC_INFORMATION mem_info;
- GC_word alloc_len;
- if (VirtualQuery(start_addr, &mem_info, sizeof(mem_info))
- != sizeof(mem_info))
- ABORT("Weird VirtualQuery result");
- alloc_len = (len < mem_info.RegionSize) ? len : mem_info.RegionSize;
- result = VirtualAlloc(start_addr, alloc_len,
- MEM_COMMIT,
- PAGE_EXECUTE_READWRITE);
- if (result != start_addr) {
- if (GetLastError() == ERROR_NOT_ENOUGH_MEMORY ||
- GetLastError() == ERROR_OUTOFMEMORY) {
- ABORT("Not enough memory to process remapping");
- } else {
- ABORT("VirtualAlloc remapping failed");
- }
- }
- GC_unmapped_bytes -= alloc_len;
- start_addr += alloc_len;
- len -= alloc_len;
- }
-# else
- /* It was already remapped with PROT_NONE. */
- int result;
-
- if (0 == start_addr) return;
- result = mprotect(start_addr, len,
- PROT_READ | PROT_WRITE | OPT_PROT_EXEC);
- if (result != 0) {
- GC_err_printf(
- "Mprotect failed at %p (length %ld) with errno %d\n",
- start_addr, (unsigned long)len, errno);
- ABORT("Mprotect remapping failed");
- }
- GC_unmapped_bytes -= len;
-# endif
-}
-
-/* Two adjacent blocks have already been unmapped and are about to */
-/* be merged. Unmap the whole block. This typically requires */
-/* that we unmap a small section in the middle that was not previously */
-/* unmapped due to alignment constraints. */
-GC_INNER void GC_unmap_gap(ptr_t start1, size_t bytes1, ptr_t start2,
- size_t bytes2)
-{
- ptr_t start1_addr = GC_unmap_start(start1, bytes1);
- ptr_t end1_addr = GC_unmap_end(start1, bytes1);
- ptr_t start2_addr = GC_unmap_start(start2, bytes2);
- ptr_t start_addr = end1_addr;
- ptr_t end_addr = start2_addr;
- size_t len;
- GC_ASSERT(start1 + bytes1 == start2);
- if (0 == start1_addr) start_addr = GC_unmap_start(start1, bytes1 + bytes2);
- if (0 == start2_addr) end_addr = GC_unmap_end(start1, bytes1 + bytes2);
- if (0 == start_addr) return;
- len = end_addr - start_addr;
-# if defined(MSWIN32) || defined(MSWINCE)
- while (len != 0) {
- MEMORY_BASIC_INFORMATION mem_info;
- GC_word free_len;
- if (VirtualQuery(start_addr, &mem_info, sizeof(mem_info))
- != sizeof(mem_info))
- ABORT("Weird VirtualQuery result");
- free_len = (len < mem_info.RegionSize) ? len : mem_info.RegionSize;
- if (!VirtualFree(start_addr, free_len, MEM_DECOMMIT))
- ABORT("VirtualFree failed");
- GC_unmapped_bytes += free_len;
- start_addr += free_len;
- len -= free_len;
- }
-# else
- if (len != 0) {
- /* Immediately remap as above. */
- void * result;
- result = mmap(start_addr, len, PROT_NONE,
- MAP_PRIVATE | MAP_FIXED | OPT_MAP_ANON,
- zero_fd, 0/* offset */);
- if (result != (void *)start_addr) ABORT("mmap(...PROT_NONE...) failed");
- }
- GC_unmapped_bytes += len;
-# endif
-}
-
-#endif /* USE_MUNMAP */
-
-/* Routine for pushing any additional roots. In THREADS */
-/* environment, this is also responsible for marking from */
-/* thread stacks. */
-#ifndef THREADS
- GC_INNER void (*GC_push_other_roots)(void) = 0;
-#else /* THREADS */
-
-# ifdef PCR
-PCR_ERes GC_push_thread_stack(PCR_Th_T *t, PCR_Any dummy)
-{
- struct PCR_ThCtl_TInfoRep info;
- PCR_ERes result;
-
- info.ti_stkLow = info.ti_stkHi = 0;
- result = PCR_ThCtl_GetInfo(t, &info);
- GC_push_all_stack((ptr_t)(info.ti_stkLow), (ptr_t)(info.ti_stkHi));
- return(result);
-}
-
-/* Push the contents of an old object. We treat this as stack */
-/* data only because that makes it robust against mark stack */
-/* overflow. */
-PCR_ERes GC_push_old_obj(void *p, size_t size, PCR_Any data)
-{
- GC_push_all_stack((ptr_t)p, (ptr_t)p + size);
- return(PCR_ERes_okay);
-}
-
-extern struct PCR_MM_ProcsRep * GC_old_allocator;
- /* defined in pcr_interface.c. */
-
-STATIC void GC_default_push_other_roots(void)
-{
- /* Traverse data allocated by previous memory managers. */
- if ((*(GC_old_allocator->mmp_enumerate))(PCR_Bool_false,
- GC_push_old_obj, 0)
- != PCR_ERes_okay) {
- ABORT("Old object enumeration failed");
- }
- /* Traverse all thread stacks. */
- if (PCR_ERes_IsErr(
- PCR_ThCtl_ApplyToAllOtherThreads(GC_push_thread_stack,0))
- || PCR_ERes_IsErr(GC_push_thread_stack(PCR_Th_CurrThread(), 0))) {
- ABORT("Thread stack marking failed\n");
- }
-}
-
-# endif /* PCR */
-
-
-# if defined(GC_PTHREADS) || defined(GC_WIN32_THREADS)
-
-GC_INNER void GC_push_all_stacks(void);
-
-STATIC void GC_default_push_other_roots(void)
-{
- GC_push_all_stacks();
-}
-
-# endif /* GC_WIN32_THREADS || GC_PTHREADS */
-
- GC_INNER void (*GC_push_other_roots)(void) = GC_default_push_other_roots;
-
-#endif /* THREADS */
-
-/*
- * Routines for accessing dirty bits on virtual pages.
- * There are six ways to maintain this information:
- * DEFAULT_VDB: A simple dummy implementation that treats every page
- * as possibly dirty. This makes incremental collection
- * useless, but the implementation is still correct.
- * MANUAL_VDB: Stacks and static data are always considered dirty.
- * Heap pages are considered dirty if GC_dirty(p) has been
- * called on some pointer p pointing to somewhere inside
- * an object on that page. A GC_dirty() call on a large
- * object directly dirties only a single page, but for
- * MANUAL_VDB we are careful to treat an object with a dirty
- * page as completely dirty.
- * In order to avoid races, an object must be marked dirty
- * after it is written, and a reference to the object
- * must be kept on a stack or in a register in the interim.
- * With threads enabled, an object directly reachable from the
- * stack at the time of a collection is treated as dirty.
- * In single-threaded mode, it suffices to ensure that no
- * collection can take place between the pointer assignment
- * and the GC_dirty() call.
- * PCR_VDB: Use PPCRs virtual dirty bit facility.
- * PROC_VDB: Use the /proc facility for reading dirty bits. Only
- * works under some SVR4 variants. Even then, it may be
- * too slow to be entirely satisfactory. Requires reading
- * dirty bits for entire address space. Implementations tend
- * to assume that the client is a (slow) debugger.
- * MPROTECT_VDB:Protect pages and then catch the faults to keep track of
- * dirtied pages. The implementation (and implementability)
- * is highly system dependent. This usually fails when system
- * calls write to a protected page. We prevent the read system
- * call from doing so. It is the clients responsibility to
- * make sure that other system calls are similarly protected
- * or write only to the stack.
- * GWW_VDB: Use the Win32 GetWriteWatch functions, if available, to
- * read dirty bits. In case it is not available (because we
- * are running on Windows 95, Windows 2000 or earlier),
- * MPROTECT_VDB may be defined as a fallback strategy.
- */
-GC_INNER GC_bool GC_dirty_maintained = FALSE;
-
-#if defined(PROC_VDB) || defined(GWW_VDB)
-
-/* Add all pages in pht2 to pht1 */
-STATIC void GC_or_pages(page_hash_table pht1, page_hash_table pht2)
-{
- register int i;
-
- for (i = 0; i < PHT_SIZE; i++) pht1[i] |= pht2[i];
-}
-
-#endif
-
-#ifdef GWW_VDB
-
-# define GC_GWW_BUF_LEN (MAXHINCR * HBLKSIZE / 4096 /* X86 page size */)
- /* Still susceptible to overflow, if there are very large allocations, */
- /* and everything is dirty. */
- static PVOID gww_buf[GC_GWW_BUF_LEN];
-
-# ifdef MPROTECT_VDB
- GC_INNER GC_bool GC_gww_dirty_init(void)
- {
- detect_GetWriteWatch();
- return GC_GWW_AVAILABLE();
- }
-# else
- GC_INNER void GC_dirty_init(void)
- {
- detect_GetWriteWatch();
- GC_dirty_maintained = GC_GWW_AVAILABLE();
- }
-# endif
-
-# ifdef MPROTECT_VDB
- STATIC void GC_gww_read_dirty(void)
-# else
- GC_INNER void GC_read_dirty(void)
-# endif
- {
- word i;
-
- BZERO(GC_grungy_pages, sizeof(GC_grungy_pages));
-
- for (i = 0; i != GC_n_heap_sects; ++i) {
- GC_ULONG_PTR count;
-
- do {
- PVOID * pages, * pages_end;
- DWORD page_size;
-
- pages = gww_buf;
- count = GC_GWW_BUF_LEN;
- /*
- * GetWriteWatch is documented as returning non-zero when it fails,
- * but the documentation doesn't explicitly say why it would fail or
- * what its behaviour will be if it fails.
- * It does appear to fail, at least on recent W2K instances, if
- * the underlying memory was not allocated with the appropriate
- * flag. This is common if GC_enable_incremental is called
- * shortly after GC initialization. To avoid modifying the
- * interface, we silently work around such a failure, it it only
- * affects the initial (small) heap allocation.
- * If there are more dirty
- * pages than will fit in the buffer, this is not treated as a
- * failure; we must check the page count in the loop condition.
- * Since each partial call will reset the status of some
- * pages, this should eventually terminate even in the overflow
- * case.
- */
- if (GetWriteWatch_func(WRITE_WATCH_FLAG_RESET,
- GC_heap_sects[i].hs_start,
- GC_heap_sects[i].hs_bytes,
- pages,
- &count,
- &page_size) != 0) {
- static int warn_count = 0;
- unsigned j;
- struct hblk * start = (struct hblk *)GC_heap_sects[i].hs_start;
- static struct hblk *last_warned = 0;
- size_t nblocks = divHBLKSZ(GC_heap_sects[i].hs_bytes);
-
- if ( i != 0 && last_warned != start && warn_count++ < 5) {
- last_warned = start;
- WARN(
- "GC_gww_read_dirty unexpectedly failed at %p: "
- "Falling back to marking all pages dirty\n", start);
- }
- for (j = 0; j < nblocks; ++j) {
- word hash = PHT_HASH(start + j);
- set_pht_entry_from_index(GC_grungy_pages, hash);
- }
- count = 1; /* Done with this section. */
- } else /* succeeded */{
- pages_end = pages + count;
- while (pages != pages_end) {
- struct hblk * h = (struct hblk *) *pages++;
- struct hblk * h_end = (struct hblk *) ((char *) h + page_size);
- do
- set_pht_entry_from_index(GC_grungy_pages, PHT_HASH(h));
- while (++h < h_end);
- }
- }
- } while (count == GC_GWW_BUF_LEN);
- /* FIXME: It's unclear from Microsoft's documentation if this loop */
- /* is useful. We suspect the call just fails if the buffer fills */
- /* up. But that should still be handled correctly. */
- }
-
- GC_or_pages(GC_written_pages, GC_grungy_pages);
- }
-
-# ifdef MPROTECT_VDB
- STATIC GC_bool GC_gww_page_was_dirty(struct hblk * h)
-# else
- GC_INNER GC_bool GC_page_was_dirty(struct hblk * h)
-# endif
- {
- return HDR(h) == 0 ||
- get_pht_entry_from_index(GC_grungy_pages, PHT_HASH(h));
- }
-
-#if 0
- /* Used only if PROC_VDB. */
-# ifdef MPROTECT_VDB
- STATIC GC_bool GC_gww_page_was_ever_dirty(struct hblk * h)
-# else
- GC_INNER GC_bool GC_page_was_ever_dirty(struct hblk * h)
-# endif
- {
- return HDR(h) == 0 ||
- get_pht_entry_from_index(GC_written_pages, PHT_HASH(h));
- }
-#endif
-
-# ifndef MPROTECT_VDB
- /*ARGSUSED*/
- GC_INNER void GC_remove_protection(struct hblk *h, word nblocks,
- GC_bool is_ptrfree) {}
-# endif
-
-# endif /* GWW_VDB */
-
-# ifdef DEFAULT_VDB
-
-/* All of the following assume the allocation lock is held. */
-
-/* The client asserts that unallocated pages in the heap are never */
-/* written. */
-
-/* Initialize virtual dirty bit implementation. */
-GC_INNER void GC_dirty_init(void)
-{
- if (GC_print_stats == VERBOSE)
- GC_log_printf("Initializing DEFAULT_VDB...\n");
- GC_dirty_maintained = TRUE;
-}
-
-/* Retrieve system dirty bits for heap to a local buffer. */
-/* Restore the systems notion of which pages are dirty. */
-GC_INNER void GC_read_dirty(void) {}
-
-/* Is the HBLKSIZE sized page at h marked dirty in the local buffer? */
-/* If the actual page size is different, this returns TRUE if any */
-/* of the pages overlapping h are dirty. This routine may err on the */
-/* side of labeling pages as dirty (and this implementation does). */
-/*ARGSUSED*/
-GC_INNER GC_bool GC_page_was_dirty(struct hblk *h)
-{
- return(TRUE);
-}
-
-/*
- * The following two routines are typically less crucial. They matter
- * most with large dynamic libraries, or if we can't accurately identify
- * stacks, e.g. under Solaris 2.X. Otherwise the following default
- * versions are adequate.
- */
-
-#if 0
-/* Could any valid GC heap pointer ever have been written to this page? */
-/*ARGSUSED*/
-GC_INNER GC_bool GC_page_was_ever_dirty(struct hblk *h)
-{
- return(TRUE);
-}
-#endif
-
-/* A call that: */
-/* I) hints that [h, h+nblocks) is about to be written. */
-/* II) guarantees that protection is removed. */
-/* (I) may speed up some dirty bit implementations. */
-/* (II) may be essential if we need to ensure that */
-/* pointer-free system call buffers in the heap are */
-/* not protected. */
-/*ARGSUSED*/
-GC_INNER void GC_remove_protection(struct hblk *h, word nblocks,
- GC_bool is_ptrfree) {}
-
-# endif /* DEFAULT_VDB */
-
-# ifdef MANUAL_VDB
-
-/* Initialize virtual dirty bit implementation. */
-GC_INNER void GC_dirty_init(void)
-{
- if (GC_print_stats == VERBOSE)
- GC_log_printf("Initializing MANUAL_VDB...\n");
- /* GC_dirty_pages and GC_grungy_pages are already cleared. */
- GC_dirty_maintained = TRUE;
-}
-
-/* Retrieve system dirty bits for heap to a local buffer. */
-/* Restore the systems notion of which pages are dirty. */
-GC_INNER void GC_read_dirty(void)
-{
- BCOPY((word *)GC_dirty_pages, GC_grungy_pages,
- (sizeof GC_dirty_pages));
- BZERO((word *)GC_dirty_pages, (sizeof GC_dirty_pages));
-}
-
-/* Is the HBLKSIZE sized page at h marked dirty in the local buffer? */
-/* If the actual page size is different, this returns TRUE if any */
-/* of the pages overlapping h are dirty. This routine may err on the */
-/* side of labeling pages as dirty (and this implementation does). */
-GC_INNER GC_bool GC_page_was_dirty(struct hblk *h)
-{
- register word index;
-
- index = PHT_HASH(h);
- return(HDR(h) == 0 || get_pht_entry_from_index(GC_grungy_pages, index));
-}
-
-/* Mark the page containing p as dirty. Logically, this dirties the */
-/* entire object. */
-void GC_dirty(ptr_t p)
-{
- word index = PHT_HASH(p);
- async_set_pht_entry_from_index(GC_dirty_pages, index);
-}
-
-/*ARGSUSED*/
-GC_INNER void GC_remove_protection(struct hblk *h, word nblocks,
- GC_bool is_ptrfree) {}
-
-# endif /* MANUAL_VDB */
-
-
-# ifdef MPROTECT_VDB
-
-/*
- * See DEFAULT_VDB for interface descriptions.
- */
-
-/*
- * This implementation maintains dirty bits itself by catching write
- * faults and keeping track of them. We assume nobody else catches
- * SIGBUS or SIGSEGV. We assume no write faults occur in system calls.
- * This means that clients must ensure that system calls don't write
- * to the write-protected heap. Probably the best way to do this is to
- * ensure that system calls write at most to POINTERFREE objects in the
- * heap, and do even that only if we are on a platform on which those
- * are not protected. Another alternative is to wrap system calls
- * (see example for read below), but the current implementation holds
- * applications.
- * We assume the page size is a multiple of HBLKSIZE.
- * We prefer them to be the same. We avoid protecting POINTERFREE
- * objects only if they are the same.
- */
-
-# if !defined(MSWIN32) && !defined(MSWINCE) && !defined(DARWIN)
-
-# include <sys/mman.h>
-# include <signal.h>
-# include <sys/syscall.h>
-
-# define PROTECT(addr, len) \
- if (mprotect((caddr_t)(addr), (size_t)(len), \
- PROT_READ | OPT_PROT_EXEC) < 0) { \
- ABORT("mprotect failed"); \
- }
-# define UNPROTECT(addr, len) \
- if (mprotect((caddr_t)(addr), (size_t)(len), \
- PROT_WRITE | PROT_READ | OPT_PROT_EXEC ) < 0) { \
- ABORT("un-mprotect failed"); \
- }
-
-# else
-
-# ifdef DARWIN
- /* Using vm_protect (mach syscall) over mprotect (BSD syscall) seems to
- decrease the likelihood of some of the problems described below. */
-# include <mach/vm_map.h>
- STATIC mach_port_t GC_task_self = 0;
-# define PROTECT(addr,len) \
- if(vm_protect(GC_task_self,(vm_address_t)(addr),(vm_size_t)(len), \
- FALSE,VM_PROT_READ) != KERN_SUCCESS) { \
- ABORT("vm_protect (PROTECT) failed"); \
- }
-# define UNPROTECT(addr,len) \
- if(vm_protect(GC_task_self,(vm_address_t)(addr),(vm_size_t)(len), \
- FALSE,VM_PROT_READ|VM_PROT_WRITE) != KERN_SUCCESS) { \
- ABORT("vm_protect (UNPROTECT) failed"); \
- }
-# else
-
-# ifndef MSWINCE
-# include <signal.h>
-# endif
-
- static DWORD protect_junk;
-# define PROTECT(addr, len) \
- if (!VirtualProtect((addr), (len), PAGE_EXECUTE_READ, \
- &protect_junk)) { \
- GC_printf("Last error code: 0x%lx\n", (long)GetLastError()); \
- ABORT("VirtualProtect failed"); \
- }
-# define UNPROTECT(addr, len) \
- if (!VirtualProtect((addr), (len), PAGE_EXECUTE_READWRITE, \
- &protect_junk)) { \
- ABORT("un-VirtualProtect failed"); \
- }
-# endif /* !DARWIN */
-# endif /* MSWIN32 || MSWINCE || DARWIN */
-
-#if defined(MSWIN32)
- typedef LPTOP_LEVEL_EXCEPTION_FILTER SIG_HNDLR_PTR;
-# undef SIG_DFL
-# define SIG_DFL (LPTOP_LEVEL_EXCEPTION_FILTER)((signed_word)-1)
-#elif defined(MSWINCE)
- typedef LONG (WINAPI *SIG_HNDLR_PTR)(struct _EXCEPTION_POINTERS *);
-# undef SIG_DFL
-# define SIG_DFL (SIG_HNDLR_PTR) (-1)
-#elif defined(DARWIN)
- typedef void (* SIG_HNDLR_PTR)();
-#else
- typedef void (* SIG_HNDLR_PTR)(int, siginfo_t *, void *);
- typedef void (* PLAIN_HNDLR_PTR)(int);
-#endif
-
-#if defined(__GLIBC__)
-# if __GLIBC__ < 2 || __GLIBC__ == 2 && __GLIBC_MINOR__ < 2
-# error glibc too old?
-# endif
-#endif
-
-#ifndef DARWIN
- STATIC SIG_HNDLR_PTR GC_old_segv_handler = 0;
- /* Also old MSWIN32 ACCESS_VIOLATION filter */
-# if !defined(MSWIN32) && !defined(MSWINCE)
- STATIC SIG_HNDLR_PTR GC_old_bus_handler = 0;
- STATIC GC_bool GC_old_bus_handler_used_si = FALSE;
- STATIC GC_bool GC_old_segv_handler_used_si = FALSE;
-# endif
-#endif /* !DARWIN */
-
-#if defined(THREADS)
-/* We need to lock around the bitmap update in the write fault handler */
-/* in order to avoid the risk of losing a bit. We do this with a */
-/* test-and-set spin lock if we know how to do that. Otherwise we */
-/* check whether we are already in the handler and use the dumb but */
-/* safe fallback algorithm of setting all bits in the word. */
-/* Contention should be very rare, so we do the minimum to handle it */
-/* correctly. */
-#ifdef AO_HAVE_test_and_set_acquire
- GC_INNER volatile AO_TS_t GC_fault_handler_lock = AO_TS_INITIALIZER;
- static void async_set_pht_entry_from_index(volatile page_hash_table db,
- size_t index)
- {
- while (AO_test_and_set_acquire(&GC_fault_handler_lock) == AO_TS_SET) {
- /* empty */
- }
- /* Could also revert to set_pht_entry_from_index_safe if initial */
- /* GC_test_and_set fails. */
- set_pht_entry_from_index(db, index);
- AO_CLEAR(&GC_fault_handler_lock);
- }
-#else /* !AO_HAVE_test_and_set_acquire */
-# error No test_and_set operation: Introduces a race.
- /* THIS WOULD BE INCORRECT! */
- /* The dirty bit vector may be temporarily wrong, */
- /* just before we notice the conflict and correct it. We may end up */
- /* looking at it while it's wrong. But this requires contention */
- /* exactly when a GC is triggered, which seems far less likely to */
- /* fail than the old code, which had no reported failures. Thus we */
- /* leave it this way while we think of something better, or support */
- /* GC_test_and_set on the remaining platforms. */
- static volatile word currently_updating = 0;
- static void async_set_pht_entry_from_index(volatile page_hash_table db,
- size_t index)
- {
- unsigned int update_dummy;
- currently_updating = (word)(&update_dummy);
- set_pht_entry_from_index(db, index);
- /* If we get contention in the 10 or so instruction window here, */
- /* and we get stopped by a GC between the two updates, we lose! */
- if (currently_updating != (word)(&update_dummy)) {
- set_pht_entry_from_index_safe(db, index);
- /* We claim that if two threads concurrently try to update the */
- /* dirty bit vector, the first one to execute UPDATE_START */
- /* will see it changed when UPDATE_END is executed. (Note that */
- /* &update_dummy must differ in two distinct threads.) It */
- /* will then execute set_pht_entry_from_index_safe, thus */
- /* returning us to a safe state, though not soon enough. */
- }
- }
-#endif /* !AO_HAVE_test_and_set_acquire */
-#else /* !THREADS */
-# define async_set_pht_entry_from_index(db, index) \
- set_pht_entry_from_index(db, index)
-#endif /* !THREADS */
-
-#ifdef CHECKSUMS
- void GC_record_fault(struct hblk * h);
- /* From checksums.c */
-#endif
-
-#if !defined(DARWIN)
-# include <errno.h>
-# if defined(FREEBSD)
-# define SIG_OK TRUE
-# define CODE_OK (si -> si_code == BUS_PAGE_FAULT)
-# elif defined(OSF1)
-# define SIG_OK (sig == SIGSEGV)
-# define CODE_OK (si -> si_code == 2 /* experimentally determined */)
-# elif defined(IRIX5)
-# define SIG_OK (sig == SIGSEGV)
-# define CODE_OK (si -> si_code == EACCES)
-# elif defined(HURD)
-# define SIG_OK (sig == SIGBUS || sig == SIGSEGV)
-# define CODE_OK TRUE
-# elif defined(LINUX)
-# define SIG_OK (sig == SIGSEGV)
-# define CODE_OK TRUE
- /* Empirically c.trapno == 14, on IA32, but is that useful? */
- /* Should probably consider alignment issues on other */
- /* architectures. */
-# elif defined(HPUX)
-# define SIG_OK (sig == SIGSEGV || sig == SIGBUS)
-# define CODE_OK (si -> si_code == SEGV_ACCERR) \
- || (si -> si_code == BUS_ADRERR) \
- || (si -> si_code == BUS_UNKNOWN) \
- || (si -> si_code == SEGV_UNKNOWN) \
- || (si -> si_code == BUS_OBJERR)
-# elif defined(SUNOS5SIGS)
-# define SIG_OK (sig == SIGSEGV)
-# define CODE_OK (si -> si_code == SEGV_ACCERR)
-# elif defined(MSWIN32) || defined(MSWINCE)
-# define SIG_OK (exc_info -> ExceptionRecord -> ExceptionCode \
- == STATUS_ACCESS_VIOLATION)
-# define CODE_OK (exc_info -> ExceptionRecord -> ExceptionInformation[0] \
- == 1) /* Write fault */
-# endif
-
-# if defined(MSWIN32) || defined(MSWINCE)
- GC_INNER LONG WINAPI GC_write_fault_handler(
- struct _EXCEPTION_POINTERS *exc_info)
-# else
-# include <ucontext.h>
- /*ARGSUSED*/
- STATIC void GC_write_fault_handler(int sig, siginfo_t *si, void *raw_sc)
-# endif /* MSWIN32 || MSWINCE */
-{
-# if !defined(MSWIN32) && !defined(MSWINCE)
- char *addr = si -> si_addr;
-# else
- char * addr = (char *) (exc_info -> ExceptionRecord
- -> ExceptionInformation[1]);
-# endif
- unsigned i;
-
- if (SIG_OK && CODE_OK) {
- register struct hblk * h =
- (struct hblk *)((word)addr & ~(GC_page_size-1));
- GC_bool in_allocd_block;
-# ifdef CHECKSUMS
- GC_record_fault(h);
-# endif /* CHECKSUMS */
-
-# ifdef SUNOS5SIGS
- /* Address is only within the correct physical page. */
- in_allocd_block = FALSE;
- for (i = 0; i < divHBLKSZ(GC_page_size); i++) {
- if (HDR(h+i) != 0) {
- in_allocd_block = TRUE;
- }
- }
-# else
- in_allocd_block = (HDR(addr) != 0);
-# endif
- if (!in_allocd_block) {
- /* FIXME - We should make sure that we invoke the */
- /* old handler with the appropriate calling */
- /* sequence, which often depends on SA_SIGINFO. */
-
- /* Heap blocks now begin and end on page boundaries */
- SIG_HNDLR_PTR old_handler;
-
-# if defined(MSWIN32) || defined(MSWINCE)
- old_handler = GC_old_segv_handler;
-# else
- GC_bool used_si;
-
- if (sig == SIGSEGV) {
- old_handler = GC_old_segv_handler;
- used_si = GC_old_segv_handler_used_si;
- } else {
- old_handler = GC_old_bus_handler;
- used_si = GC_old_bus_handler_used_si;
- }
-# endif
-
- if (old_handler == (SIG_HNDLR_PTR)SIG_DFL) {
-# if !defined(MSWIN32) && !defined(MSWINCE)
- GC_err_printf("Segfault at %p\n", addr);
- ABORT("Unexpected bus error or segmentation fault");
-# else
- return(EXCEPTION_CONTINUE_SEARCH);
-# endif
- } else {
- /*
- * FIXME: This code should probably check if the
- * old signal handler used the traditional style and
- * if so call it using that style.
- */
-# if defined(MSWIN32) || defined(MSWINCE)
- return((*old_handler)(exc_info));
-# else
- if (used_si)
- ((SIG_HNDLR_PTR)old_handler) (sig, si, raw_sc);
- else
- /* FIXME: should pass nonstandard args as well. */
- ((PLAIN_HNDLR_PTR)old_handler) (sig);
- return;
-# endif
- }
- }
- UNPROTECT(h, GC_page_size);
- /* We need to make sure that no collection occurs between */
- /* the UNPROTECT and the setting of the dirty bit. Otherwise */
- /* a write by a third thread might go unnoticed. Reversing */
- /* the order is just as bad, since we would end up unprotecting */
- /* a page in a GC cycle during which it's not marked. */
- /* Currently we do this by disabling the thread stopping */
- /* signals while this handler is running. An alternative might */
- /* be to record the fact that we're about to unprotect, or */
- /* have just unprotected a page in the GC's thread structure, */
- /* and then to have the thread stopping code set the dirty */
- /* flag, if necessary. */
- for (i = 0; i < divHBLKSZ(GC_page_size); i++) {
- size_t index = PHT_HASH(h+i);
-
- async_set_pht_entry_from_index(GC_dirty_pages, index);
- }
- /* The write may not take place before dirty bits are read. */
- /* But then we'll fault again ... */
-# if defined(MSWIN32) || defined(MSWINCE)
- return(EXCEPTION_CONTINUE_EXECUTION);
-# else
- return;
-# endif
- }
-#if defined(MSWIN32) || defined(MSWINCE)
- return EXCEPTION_CONTINUE_SEARCH;
-#else
- GC_err_printf("Segfault at %p\n", addr);
- ABORT("Unexpected bus error or segmentation fault");
-#endif
-}
-#endif /* !DARWIN */
-
-/*
- * We hold the allocation lock. We expect block h to be written
- * shortly. Ensure that all pages containing any part of the n hblks
- * starting at h are no longer protected. If is_ptrfree is false,
- * also ensure that they will subsequently appear to be dirty.
- * Not allowed to call GC_printf (and the friends) here, see Win32
- * GC_stop_world() for the information.
- */
-GC_INNER void GC_remove_protection(struct hblk *h, word nblocks,
- GC_bool is_ptrfree)
-{
- struct hblk * h_trunc; /* Truncated to page boundary */
- struct hblk * h_end; /* Page boundary following block end */
- struct hblk * current;
-
-# if defined(GWW_VDB)
- if (GC_GWW_AVAILABLE()) return;
-# endif
- if (!GC_dirty_maintained) return;
- h_trunc = (struct hblk *)((word)h & ~(GC_page_size-1));
- h_end = (struct hblk *)(((word)(h + nblocks) + GC_page_size-1)
- & ~(GC_page_size-1));
- if (h_end == h_trunc + 1 &&
- get_pht_entry_from_index(GC_dirty_pages, PHT_HASH(h_trunc))) {
- /* already marked dirty, and hence unprotected. */
- return;
- }
- for (current = h_trunc; current < h_end; ++current) {
- size_t index = PHT_HASH(current);
- if (!is_ptrfree || current < h || current >= h + nblocks) {
- async_set_pht_entry_from_index(GC_dirty_pages, index);
- }
- }
- UNPROTECT(h_trunc, (ptr_t)h_end - (ptr_t)h_trunc);
-}
-
-#if !defined(DARWIN)
- GC_INNER void GC_dirty_init(void)
- {
-# if !defined(MSWIN32) && !defined(MSWINCE)
- struct sigaction act, oldact;
- act.sa_flags = SA_RESTART | SA_SIGINFO;
- act.sa_sigaction = GC_write_fault_handler;
- (void)sigemptyset(&act.sa_mask);
-# ifdef SIG_SUSPEND
- /* Arrange to postpone SIG_SUSPEND while we're in a write fault */
- /* handler. This effectively makes the handler atomic w.r.t. */
- /* stopping the world for GC. */
- (void)sigaddset(&act.sa_mask, SIG_SUSPEND);
-# endif /* SIG_SUSPEND */
-# endif
- if (GC_print_stats == VERBOSE)
- GC_log_printf(
- "Initializing mprotect virtual dirty bit implementation\n");
- GC_dirty_maintained = TRUE;
- if (GC_page_size % HBLKSIZE != 0) {
- GC_err_printf("Page size not multiple of HBLKSIZE\n");
- ABORT("Page size not multiple of HBLKSIZE");
- }
-# if !defined(MSWIN32) && !defined(MSWINCE)
-# if defined(GC_IRIX_THREADS)
- sigaction(SIGSEGV, 0, &oldact);
- sigaction(SIGSEGV, &act, 0);
-# else
- {
- int res = sigaction(SIGSEGV, &act, &oldact);
- if (res != 0) ABORT("Sigaction failed");
- }
-# endif
- if (oldact.sa_flags & SA_SIGINFO) {
- GC_old_segv_handler = oldact.sa_sigaction;
- GC_old_segv_handler_used_si = TRUE;
- } else {
- GC_old_segv_handler = (SIG_HNDLR_PTR)oldact.sa_handler;
- GC_old_segv_handler_used_si = FALSE;
- }
- if (GC_old_segv_handler == (SIG_HNDLR_PTR)SIG_IGN) {
- GC_err_printf("Previously ignored segmentation violation!?\n");
- GC_old_segv_handler = (SIG_HNDLR_PTR)SIG_DFL;
- }
- if (GC_old_segv_handler != (SIG_HNDLR_PTR)SIG_DFL) {
- if (GC_print_stats == VERBOSE)
- GC_log_printf("Replaced other SIGSEGV handler\n");
- }
-# if defined(HPUX) || defined(LINUX) || defined(HURD) \
- || (defined(FREEBSD) && defined(SUNOS5SIGS))
- sigaction(SIGBUS, &act, &oldact);
- if (oldact.sa_flags & SA_SIGINFO) {
- GC_old_bus_handler = oldact.sa_sigaction;
- GC_old_bus_handler_used_si = TRUE;
- } else {
- GC_old_bus_handler = (SIG_HNDLR_PTR)oldact.sa_handler;
- GC_old_bus_handler_used_si = FALSE;
- }
- if (GC_old_bus_handler == (SIG_HNDLR_PTR)SIG_IGN) {
- GC_err_printf("Previously ignored bus error!?\n");
- GC_old_bus_handler = (SIG_HNDLR_PTR)SIG_DFL;
- }
- if (GC_old_bus_handler != (SIG_HNDLR_PTR)SIG_DFL) {
- if (GC_print_stats == VERBOSE)
- GC_log_printf("Replaced other SIGBUS handler\n");
- }
-# endif /* HPUX || LINUX || HURD || (FREEBSD && SUNOS5SIGS) */
-# endif /* ! MS windows */
-# if defined(GWW_VDB)
- if (GC_gww_dirty_init())
- return;
-# endif
-# if defined(MSWIN32)
- GC_old_segv_handler = SetUnhandledExceptionFilter(GC_write_fault_handler);
- if (GC_old_segv_handler != NULL) {
- if (GC_print_stats)
- GC_log_printf("Replaced other UnhandledExceptionFilter\n");
- } else {
- GC_old_segv_handler = SIG_DFL;
- }
-# elif defined(MSWINCE)
- /* MPROTECT_VDB is unsupported for WinCE at present. */
- /* FIXME: implement it (if possible). */
-# endif
- }
-#endif /* !DARWIN */
-
-GC_API int GC_CALL GC_incremental_protection_needs(void)
-{
- if (GC_page_size == HBLKSIZE) {
- return GC_PROTECTS_POINTER_HEAP;
- } else {
- return GC_PROTECTS_POINTER_HEAP | GC_PROTECTS_PTRFREE_HEAP;
- }
-}
-
-#define HAVE_INCREMENTAL_PROTECTION_NEEDS
-
-#define IS_PTRFREE(hhdr) ((hhdr)->hb_descr == 0)
-
-#define PAGE_ALIGNED(x) !((word)(x) & (GC_page_size - 1))
-STATIC void GC_protect_heap(void)
-{
- ptr_t start;
- size_t len;
- struct hblk * current;
- struct hblk * current_start; /* Start of block to be protected. */
- struct hblk * limit;
- unsigned i;
- GC_bool protect_all =
- (0 != (GC_incremental_protection_needs() & GC_PROTECTS_PTRFREE_HEAP));
- for (i = 0; i < GC_n_heap_sects; i++) {
- start = GC_heap_sects[i].hs_start;
- len = GC_heap_sects[i].hs_bytes;
- if (protect_all) {
- PROTECT(start, len);
- } else {
- GC_ASSERT(PAGE_ALIGNED(len))
- GC_ASSERT(PAGE_ALIGNED(start))
- current_start = current = (struct hblk *)start;
- limit = (struct hblk *)(start + len);
- while (current < limit) {
- hdr * hhdr;
- word nhblks;
- GC_bool is_ptrfree;
-
- GC_ASSERT(PAGE_ALIGNED(current));
- GET_HDR(current, hhdr);
- if (IS_FORWARDING_ADDR_OR_NIL(hhdr)) {
- /* This can happen only if we're at the beginning of a */
- /* heap segment, and a block spans heap segments. */
- /* We will handle that block as part of the preceding */
- /* segment. */
- GC_ASSERT(current_start == current);
- current_start = ++current;
- continue;
- }
- if (HBLK_IS_FREE(hhdr)) {
- GC_ASSERT(PAGE_ALIGNED(hhdr -> hb_sz));
- nhblks = divHBLKSZ(hhdr -> hb_sz);
- is_ptrfree = TRUE; /* dirty on alloc */
- } else {
- nhblks = OBJ_SZ_TO_BLOCKS(hhdr -> hb_sz);
- is_ptrfree = IS_PTRFREE(hhdr);
- }
- if (is_ptrfree) {
- if (current_start < current) {
- PROTECT(current_start, (ptr_t)current - (ptr_t)current_start);
- }
- current_start = (current += nhblks);
- } else {
- current += nhblks;
- }
- }
- if (current_start < current) {
- PROTECT(current_start, (ptr_t)current - (ptr_t)current_start);
- }
- }
- }
-}
-
-/* We assume that either the world is stopped or its OK to lose dirty */
-/* bits while this is happenning (as in GC_enable_incremental). */
-GC_INNER void GC_read_dirty(void)
-{
-# if defined(GWW_VDB)
- if (GC_GWW_AVAILABLE()) {
- GC_gww_read_dirty();
- return;
- }
-# endif
- BCOPY((word *)GC_dirty_pages, GC_grungy_pages,
- (sizeof GC_dirty_pages));
- BZERO((word *)GC_dirty_pages, (sizeof GC_dirty_pages));
- GC_protect_heap();
-}
-
-GC_INNER GC_bool GC_page_was_dirty(struct hblk *h)
-{
- register word index;
-
-# if defined(GWW_VDB)
- if (GC_GWW_AVAILABLE())
- return GC_gww_page_was_dirty(h);
-# endif
-
- index = PHT_HASH(h);
- return(HDR(h) == 0 || get_pht_entry_from_index(GC_grungy_pages, index));
-}
-
-/*
- * Acquiring the allocation lock here is dangerous, since this
- * can be called from within GC_call_with_alloc_lock, and the cord
- * package does so. On systems that allow nested lock acquisition, this
- * happens to work.
- * On other systems, SET_LOCK_HOLDER and friends must be suitably defined.
- */
-
-#if 0
-static GC_bool syscall_acquired_lock = FALSE; /* Protected by GC lock. */
-
-void GC_begin_syscall(void)
-{
- /* FIXME: Resurrecting this code would require fixing the */
- /* test, which can spuriously return TRUE. */
- if (!I_HOLD_LOCK()) {
- LOCK();
- syscall_acquired_lock = TRUE;
- }
-}
-
-void GC_end_syscall(void)
-{
- if (syscall_acquired_lock) {
- syscall_acquired_lock = FALSE;
- UNLOCK();
- }
-}
-
-void GC_unprotect_range(ptr_t addr, word len)
-{
- struct hblk * start_block;
- struct hblk * end_block;
- register struct hblk *h;
- ptr_t obj_start;
-
- if (!GC_dirty_maintained) return;
- obj_start = GC_base(addr);
- if (obj_start == 0) return;
- if (GC_base(addr + len - 1) != obj_start) {
- ABORT("GC_unprotect_range(range bigger than object)");
- }
- start_block = (struct hblk *)((word)addr & ~(GC_page_size - 1));
- end_block = (struct hblk *)((word)(addr + len - 1) & ~(GC_page_size - 1));
- end_block += GC_page_size/HBLKSIZE - 1;
- for (h = start_block; h <= end_block; h++) {
- register word index = PHT_HASH(h);
-
- async_set_pht_entry_from_index(GC_dirty_pages, index);
- }
- UNPROTECT(start_block,
- ((ptr_t)end_block - (ptr_t)start_block) + HBLKSIZE);
-}
-
-
-/* We no longer wrap read by default, since that was causing too many */
-/* problems. It is preferred that the client instead avoids writing */
-/* to the write-protected heap with a system call. */
-/* This still serves as sample code if you do want to wrap system calls.*/
-
-#if !defined(MSWIN32) && !defined(MSWINCE) && !defined(GC_USE_LD_WRAP)
-/* Replacement for UNIX system call. */
-/* Other calls that write to the heap should be handled similarly. */
-/* Note that this doesn't work well for blocking reads: It will hold */
-/* the allocation lock for the entire duration of the call. Multithreaded */
-/* clients should really ensure that it won't block, either by setting */
-/* the descriptor nonblocking, or by calling select or poll first, to */
-/* make sure that input is available. */
-/* Another, preferred alternative is to ensure that system calls never */
-/* write to the protected heap (see above). */
-# include <unistd.h>
-# include <sys/uio.h>
-ssize_t read(int fd, void *buf, size_t nbyte)
-{
- int result;
-
- GC_begin_syscall();
- GC_unprotect_range(buf, (word)nbyte);
-# if defined(IRIX5) || defined(GC_LINUX_THREADS)
- /* Indirect system call may not always be easily available. */
- /* We could call _read, but that would interfere with the */
- /* libpthread interception of read. */
- /* On Linux, we have to be careful with the linuxthreads */
- /* read interception. */
- {
- struct iovec iov;
-
- iov.iov_base = buf;
- iov.iov_len = nbyte;
- result = readv(fd, &iov, 1);
- }
-# else
-# if defined(HURD)
- result = __read(fd, buf, nbyte);
-# else
- /* The two zero args at the end of this list are because one
- IA-64 syscall() implementation actually requires six args
- to be passed, even though they aren't always used. */
- result = syscall(SYS_read, fd, buf, nbyte, 0, 0);
-# endif /* !HURD */
-# endif
- GC_end_syscall();
- return(result);
-}
-#endif /* !MSWIN32 && !MSWINCE && !GC_LINUX_THREADS */
-
-#if defined(GC_USE_LD_WRAP) && !defined(THREADS)
- /* We use the GNU ld call wrapping facility. */
- /* This requires that the linker be invoked with "--wrap read". */
- /* This can be done by passing -Wl,"--wrap read" to gcc. */
- /* I'm not sure that this actually wraps whatever version of read */
- /* is called by stdio. That code also mentions __read. */
-# include <unistd.h>
- ssize_t __wrap_read(int fd, void *buf, size_t nbyte)
- {
- int result;
-
- GC_begin_syscall();
- GC_unprotect_range(buf, (word)nbyte);
- result = __real_read(fd, buf, nbyte);
- GC_end_syscall();
- return(result);
- }
-
- /* We should probably also do this for __read, or whatever stdio */
- /* actually calls. */
-#endif
-
-/*ARGSUSED*/
-GC_INNER GC_bool GC_page_was_ever_dirty(struct hblk *h)
-{
-# if defined(GWW_VDB)
- if (GC_GWW_AVAILABLE())
- return GC_gww_page_was_ever_dirty(h);
-# endif
- return(TRUE);
-}
-
-#endif /* 0 */
-
-# endif /* MPROTECT_VDB */
-
-# ifdef PROC_VDB
-
-/*
- * See DEFAULT_VDB for interface descriptions.
- */
-
-/*
- * This implementation assumes a Solaris 2.X like /proc pseudo-file-system
- * from which we can read page modified bits. This facility is far from
- * optimal (e.g. we would like to get the info for only some of the
- * address space), but it avoids intercepting system calls.
- */
-
-#include <errno.h>
-#include <sys/types.h>
-#include <sys/signal.h>
-#include <sys/fault.h>
-#include <sys/syscall.h>
-#include <sys/procfs.h>
-#include <sys/stat.h>
-
-#define INITIAL_BUF_SZ 16384
-STATIC word GC_proc_buf_size = INITIAL_BUF_SZ;
-STATIC char *GC_proc_buf = NULL;
-
-STATIC int GC_proc_fd = 0;
-
-GC_INNER void GC_dirty_init(void)
-{
- int fd;
- char buf[30];
-
- GC_dirty_maintained = TRUE;
- if (GC_bytes_allocd != 0 || GC_bytes_allocd_before_gc != 0) {
- register int i;
-
- for (i = 0; i < PHT_SIZE; i++) GC_written_pages[i] = (word)(-1);
- if (GC_print_stats == VERBOSE)
- GC_log_printf(
- "Allocated bytes:%lu:all pages may have been written\n",
- (unsigned long)
- (GC_bytes_allocd + GC_bytes_allocd_before_gc));
- }
- sprintf(buf, "/proc/%ld", (long)getpid());
- fd = open(buf, O_RDONLY);
- if (fd < 0) {
- ABORT("/proc open failed");
- }
- GC_proc_fd = syscall(SYS_ioctl, fd, PIOCOPENPD, 0);
- close(fd);
- syscall(SYS_fcntl, GC_proc_fd, F_SETFD, FD_CLOEXEC);
- if (GC_proc_fd < 0) {
- ABORT("/proc ioctl failed");
- }
- GC_proc_buf = GC_scratch_alloc(GC_proc_buf_size);
-}
-
-/* Ignore write hints. They don't help us here. */
-/*ARGSUSED*/
-GC_INNER void GC_remove_protection(struct hblk *h, word nblocks,
- GC_bool is_ptrfree) {}
-
-# define READ(fd,buf,nbytes) read(fd, buf, nbytes)
-
-GC_INNER void GC_read_dirty(void)
-{
- unsigned long ps, np;
- int nmaps;
- ptr_t vaddr;
- struct prasmap * map;
- char * bufp;
- ptr_t current_addr, limit;
- int i;
-
- BZERO(GC_grungy_pages, (sizeof GC_grungy_pages));
-
- bufp = GC_proc_buf;
- if (READ(GC_proc_fd, bufp, GC_proc_buf_size) <= 0) {
- if (GC_print_stats)
- GC_log_printf("/proc read failed: GC_proc_buf_size = %lu\n",
- (unsigned long)GC_proc_buf_size);
- {
- /* Retry with larger buffer. */
- word new_size = 2 * GC_proc_buf_size;
- char * new_buf = GC_scratch_alloc(new_size);
-
- if (new_buf != 0) {
- GC_proc_buf = bufp = new_buf;
- GC_proc_buf_size = new_size;
- }
- if (READ(GC_proc_fd, bufp, GC_proc_buf_size) <= 0) {
- WARN("Insufficient space for /proc read\n", 0);
- /* Punt: */
- memset(GC_grungy_pages, 0xff, sizeof (page_hash_table));
- memset(GC_written_pages, 0xff, sizeof(page_hash_table));
- return;
- }
- }
- }
- /* Copy dirty bits into GC_grungy_pages */
- nmaps = ((struct prpageheader *)bufp) -> pr_nmap;
- /* printf( "nmaps = %d, PG_REFERENCED = %d, PG_MODIFIED = %d\n",
- nmaps, PG_REFERENCED, PG_MODIFIED); */
- bufp = bufp + sizeof(struct prpageheader);
- for (i = 0; i < nmaps; i++) {
- map = (struct prasmap *)bufp;
- vaddr = (ptr_t)(map -> pr_vaddr);
- ps = map -> pr_pagesize;
- np = map -> pr_npage;
- /* printf("vaddr = 0x%X, ps = 0x%X, np = 0x%X\n", vaddr, ps, np); */
- limit = vaddr + ps * np;
- bufp += sizeof (struct prasmap);
- for (current_addr = vaddr;
- current_addr < limit; current_addr += ps) {
- if ((*bufp++) & PG_MODIFIED) {
- register struct hblk * h = (struct hblk *) current_addr;
-
- while ((ptr_t)h < current_addr + ps) {
- register word index = PHT_HASH(h);
-
- set_pht_entry_from_index(GC_grungy_pages, index);
- h++;
- }
- }
- }
- bufp += sizeof(long) - 1;
- bufp = (char *)((unsigned long)bufp & ~(sizeof(long)-1));
- }
- /* Update GC_written_pages. */
- GC_or_pages(GC_written_pages, GC_grungy_pages);
-}
-
-#undef READ
-
-GC_INNER GC_bool GC_page_was_dirty(struct hblk *h)
-{
- register word index = PHT_HASH(h);
- return get_pht_entry_from_index(GC_grungy_pages, index);
-}
-
-GC_INNER GC_bool GC_page_was_ever_dirty(struct hblk *h)
-{
- register word index = PHT_HASH(h);
- return get_pht_entry_from_index(GC_written_pages, index);
-}
-
-# endif /* PROC_VDB */
-
-
-# ifdef PCR_VDB
-
-# include "vd/PCR_VD.h"
-
-# define NPAGES (32*1024) /* 128 MB */
-
-PCR_VD_DB GC_grungy_bits[NPAGES];
-
-STATIC ptr_t GC_vd_base = NULL;
- /* Address corresponding to GC_grungy_bits[0] */
- /* HBLKSIZE aligned. */
-
-GC_INNER void GC_dirty_init(void)
-{
- GC_dirty_maintained = TRUE;
- /* For the time being, we assume the heap generally grows up */
- GC_vd_base = GC_heap_sects[0].hs_start;
- if (GC_vd_base == 0) {
- ABORT("Bad initial heap segment");
- }
- if (PCR_VD_Start(HBLKSIZE, GC_vd_base, NPAGES*HBLKSIZE)
- != PCR_ERes_okay) {
- ABORT("dirty bit initialization failed");
- }
-}
-
-GC_INNER void GC_read_dirty(void)
-{
- /* lazily enable dirty bits on newly added heap sects */
- {
- static int onhs = 0;
- int nhs = GC_n_heap_sects;
- for(; onhs < nhs; onhs++) {
- PCR_VD_WriteProtectEnable(
- GC_heap_sects[onhs].hs_start,
- GC_heap_sects[onhs].hs_bytes );
- }
- }
-
- if (PCR_VD_Clear(GC_vd_base, NPAGES*HBLKSIZE, GC_grungy_bits)
- != PCR_ERes_okay) {
- ABORT("dirty bit read failed");
- }
-}
-
-GC_INNER GC_bool GC_page_was_dirty(struct hblk *h)
-{
- if((ptr_t)h < GC_vd_base || (ptr_t)h >= GC_vd_base + NPAGES*HBLKSIZE) {
- return(TRUE);
- }
- return(GC_grungy_bits[h - (struct hblk *)GC_vd_base] & PCR_VD_DB_dirtyBit);
-}
-
-/*ARGSUSED*/
-GC_INNER void GC_remove_protection(struct hblk *h, word nblocks,
- GC_bool is_ptrfree)
-{
- PCR_VD_WriteProtectDisable(h, nblocks*HBLKSIZE);
- PCR_VD_WriteProtectEnable(h, nblocks*HBLKSIZE);
-}
-
-# endif /* PCR_VDB */
-
-#if defined(MPROTECT_VDB) && defined(DARWIN)
-/* The following sources were used as a *reference* for this exception handling
- code:
- 1. Apple's mach/xnu documentation
- 2. Timothy J. Wood's "Mach Exception Handlers 101" post to the
- omnigroup's macosx-dev list.
- www.omnigroup.com/mailman/archive/macosx-dev/2000-June/014178.html
- 3. macosx-nat.c from Apple's GDB source code.
-*/
-
-/* The bug that caused all this trouble should now be fixed. This should
- eventually be removed if all goes well. */
-
-/* #define BROKEN_EXCEPTION_HANDLING */
-
-#include <mach/mach.h>
-#include <mach/mach_error.h>
-#include <mach/thread_status.h>
-#include <mach/exception.h>
-#include <mach/task.h>
-#include <pthread.h>
-
-/* These are not defined in any header, although they are documented */
-extern boolean_t
-exc_server(mach_msg_header_t *, mach_msg_header_t *);
-
-extern kern_return_t
-exception_raise(mach_port_t, mach_port_t, mach_port_t, exception_type_t,
- exception_data_t, mach_msg_type_number_t);
-
-extern kern_return_t
-exception_raise_state(mach_port_t, mach_port_t, mach_port_t, exception_type_t,
- exception_data_t, mach_msg_type_number_t,
- thread_state_flavor_t*, thread_state_t,
- mach_msg_type_number_t, thread_state_t,
- mach_msg_type_number_t*);
-
-extern kern_return_t
-exception_raise_state_identity(mach_port_t, mach_port_t, mach_port_t,
- exception_type_t, exception_data_t,
- mach_msg_type_number_t, thread_state_flavor_t*,
- thread_state_t, mach_msg_type_number_t,
- thread_state_t, mach_msg_type_number_t*);
-
-#define MAX_EXCEPTION_PORTS 16
-
-static struct {
- mach_msg_type_number_t count;
- exception_mask_t masks[MAX_EXCEPTION_PORTS];
- exception_handler_t ports[MAX_EXCEPTION_PORTS];
- exception_behavior_t behaviors[MAX_EXCEPTION_PORTS];
- thread_state_flavor_t flavors[MAX_EXCEPTION_PORTS];
-} GC_old_exc_ports;
-
-STATIC struct {
- mach_port_t exception;
-# if defined(THREADS)
- mach_port_t reply;
-# endif
-} GC_ports = {0};
-
-typedef struct {
- mach_msg_header_t head;
-} GC_msg_t;
-
-typedef enum {
- GC_MP_NORMAL, GC_MP_DISCARDING, GC_MP_STOPPED
-} GC_mprotect_state_t;
-
-/* FIXME: 1 and 2 seem to be safe to use in the msgh_id field,
- but it isn't documented. Use the source and see if they
- should be ok. */
-#define ID_STOP 1
-#define ID_RESUME 2
-
-/* These values are only used on the reply port */
-#define ID_ACK 3
-
-#if defined(THREADS)
-
-STATIC GC_mprotect_state_t GC_mprotect_state = 0;
-
-/* The following should ONLY be called when the world is stopped */
-STATIC void GC_mprotect_thread_notify(mach_msg_id_t id)
-{
-
- struct {
- GC_msg_t msg;
- mach_msg_trailer_t trailer;
- } buf;
-
- mach_msg_return_t r;
- /* remote, local */
- buf.msg.head.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_MAKE_SEND, 0);
- buf.msg.head.msgh_size = sizeof(buf.msg);
- buf.msg.head.msgh_remote_port = GC_ports.exception;
- buf.msg.head.msgh_local_port = MACH_PORT_NULL;
- buf.msg.head.msgh_id = id;
-
- r = mach_msg(&buf.msg.head, MACH_SEND_MSG | MACH_RCV_MSG | MACH_RCV_LARGE,
- sizeof(buf.msg), sizeof(buf), GC_ports.reply,
- MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
- if(r != MACH_MSG_SUCCESS)
- ABORT("mach_msg failed in GC_mprotect_thread_notify");
- if(buf.msg.head.msgh_id != ID_ACK)
- ABORT("invalid ack in GC_mprotect_thread_notify");
-}
-
-/* Should only be called by the mprotect thread */
-STATIC void GC_mprotect_thread_reply(void)
-{
- GC_msg_t msg;
- mach_msg_return_t r;
- /* remote, local */
- msg.head.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_MAKE_SEND, 0);
- msg.head.msgh_size = sizeof(msg);
- msg.head.msgh_remote_port = GC_ports.reply;
- msg.head.msgh_local_port = MACH_PORT_NULL;
- msg.head.msgh_id = ID_ACK;
-
- r = mach_msg(&msg.head, MACH_SEND_MSG, sizeof(msg), 0, MACH_PORT_NULL,
- MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
- if(r != MACH_MSG_SUCCESS)
- ABORT("mach_msg failed in GC_mprotect_thread_reply");
-}
-
-GC_INNER void GC_mprotect_stop(void)
-{
- GC_mprotect_thread_notify(ID_STOP);
-}
-
-GC_INNER void GC_mprotect_resume(void)
-{
- GC_mprotect_thread_notify(ID_RESUME);
-}
-
-#else /* !THREADS */
-/* The compiler should optimize away any GC_mprotect_state computations */
-#define GC_mprotect_state GC_MP_NORMAL
-#endif
-
-GC_INNER void GC_darwin_register_mach_handler_thread(mach_port_t thread);
-
-STATIC void *GC_mprotect_thread(void *arg)
-{
- mach_msg_return_t r;
- /* These two structures contain some private kernel data. We don't need to
- access any of it so we don't bother defining a proper struct. The
- correct definitions are in the xnu source code. */
- struct {
- mach_msg_header_t head;
- char data[256];
- } reply;
- struct {
- mach_msg_header_t head;
- mach_msg_body_t msgh_body;
- char data[1024];
- } msg;
-
- mach_msg_id_t id;
-
- GC_darwin_register_mach_handler_thread(mach_thread_self());
-
- for(;;) {
- r = mach_msg(&msg.head, MACH_RCV_MSG | MACH_RCV_LARGE |
- (GC_mprotect_state == GC_MP_DISCARDING ? MACH_RCV_TIMEOUT : 0),
- 0, sizeof(msg), GC_ports.exception,
- GC_mprotect_state == GC_MP_DISCARDING ? 0
- : MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
-
- id = r == MACH_MSG_SUCCESS ? msg.head.msgh_id : -1;
-
-# if defined(THREADS)
- if(GC_mprotect_state == GC_MP_DISCARDING) {
- if(r == MACH_RCV_TIMED_OUT) {
- GC_mprotect_state = GC_MP_STOPPED;
- GC_mprotect_thread_reply();
- continue;
- }
- if(r == MACH_MSG_SUCCESS && (id == ID_STOP || id == ID_RESUME))
- ABORT("out of order mprotect thread request");
- }
-# endif /* THREADS */
-
- if(r != MACH_MSG_SUCCESS) {
- GC_err_printf("mach_msg failed with %d %s\n", (int)r,
- mach_error_string(r));
- ABORT("mach_msg failed");
- }
-
- switch(id) {
-# if defined(THREADS)
- case ID_STOP:
- if(GC_mprotect_state != GC_MP_NORMAL)
- ABORT("Called mprotect_stop when state wasn't normal");
- GC_mprotect_state = GC_MP_DISCARDING;
- break;
- case ID_RESUME:
- if(GC_mprotect_state != GC_MP_STOPPED)
- ABORT("Called mprotect_resume when state wasn't stopped");
- GC_mprotect_state = GC_MP_NORMAL;
- GC_mprotect_thread_reply();
- break;
-# endif /* THREADS */
- default:
- /* Handle the message (calls catch_exception_raise) */
- if(!exc_server(&msg.head, &reply.head))
- ABORT("exc_server failed");
- /* Send the reply */
- r = mach_msg(&reply.head, MACH_SEND_MSG, reply.head.msgh_size, 0,
- MACH_PORT_NULL, MACH_MSG_TIMEOUT_NONE,
- MACH_PORT_NULL);
- if(r != MACH_MSG_SUCCESS) {
- /* This will fail if the thread dies, but the thread */
- /* shouldn't die... */
-# ifdef BROKEN_EXCEPTION_HANDLING
- GC_err_printf("mach_msg failed with %d %s while sending "
- "exc reply\n", (int)r,mach_error_string(r));
-# else
- ABORT("mach_msg failed while sending exception reply");
-# endif
- }
- } /* switch */
- } /* for(;;) */
- /* NOT REACHED */
- return NULL;
-}
-
-/* All this SIGBUS code shouldn't be necessary. All protection faults should
- be going through the mach exception handler. However, it seems a SIGBUS is
- occasionally sent for some unknown reason. Even more odd, it seems to be
- meaningless and safe to ignore. */
-#ifdef BROKEN_EXCEPTION_HANDLING
-
-/* Updates to this aren't atomic, but the SIGBUSs seem pretty rare.
- Even if this doesn't get updated property, it isn't really a problem */
-STATIC int GC_sigbus_count = 0;
-
-STATIC void GC_darwin_sigbus(int num, siginfo_t *sip, void *context)
-{
- if(num != SIGBUS)
- ABORT("Got a non-sigbus signal in the sigbus handler");
-
- /* Ugh... some seem safe to ignore, but too many in a row probably means
- trouble. GC_sigbus_count is reset for each mach exception that is
- handled */
- if(GC_sigbus_count >= 8) {
- ABORT("Got more than 8 SIGBUSs in a row!");
- } else {
- GC_sigbus_count++;
- WARN("Ignoring SIGBUS.\n", 0);
- }
-}
-#endif /* BROKEN_EXCEPTION_HANDLING */
-
-GC_INNER void GC_dirty_init(void)
-{
- kern_return_t r;
- mach_port_t me;
- pthread_t thread;
- pthread_attr_t attr;
- exception_mask_t mask;
-
- if (GC_print_stats == VERBOSE)
- GC_log_printf("Initializing mach/darwin mprotect virtual dirty bit "
- "implementation\n");
-# ifdef BROKEN_EXCEPTION_HANDLING
- WARN("Enabling workarounds for various darwin "
- "exception handling bugs.\n", 0);
-# endif
- GC_dirty_maintained = TRUE;
- if (GC_page_size % HBLKSIZE != 0) {
- GC_err_printf("Page size not multiple of HBLKSIZE\n");
- ABORT("Page size not multiple of HBLKSIZE");
- }
-
- GC_task_self = me = mach_task_self();
-
- r = mach_port_allocate(me, MACH_PORT_RIGHT_RECEIVE, &GC_ports.exception);
- if(r != KERN_SUCCESS)
- ABORT("mach_port_allocate failed (exception port)");
-
- r = mach_port_insert_right(me, GC_ports.exception, GC_ports.exception,
- MACH_MSG_TYPE_MAKE_SEND);
- if(r != KERN_SUCCESS)
- ABORT("mach_port_insert_right failed (exception port)");
-
-# if defined(THREADS)
- r = mach_port_allocate(me, MACH_PORT_RIGHT_RECEIVE, &GC_ports.reply);
- if(r != KERN_SUCCESS)
- ABORT("mach_port_allocate failed (reply port)");
-# endif
-
- /* The exceptions we want to catch */
- mask = EXC_MASK_BAD_ACCESS;
-
- r = task_get_exception_ports(me, mask, GC_old_exc_ports.masks,
- &GC_old_exc_ports.count, GC_old_exc_ports.ports,
- GC_old_exc_ports.behaviors,
- GC_old_exc_ports.flavors);
- if(r != KERN_SUCCESS)
- ABORT("task_get_exception_ports failed");
-
- r = task_set_exception_ports(me, mask, GC_ports.exception, EXCEPTION_DEFAULT,
- GC_MACH_THREAD_STATE);
- if(r != KERN_SUCCESS)
- ABORT("task_set_exception_ports failed");
- if(pthread_attr_init(&attr) != 0)
- ABORT("pthread_attr_init failed");
- if(pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED) != 0)
- ABORT("pthread_attr_setdetachedstate failed");
-
-# undef pthread_create
- /* This will call the real pthread function, not our wrapper */
- if(pthread_create(&thread, &attr, GC_mprotect_thread, NULL) != 0)
- ABORT("pthread_create failed");
- pthread_attr_destroy(&attr);
-
- /* Setup the sigbus handler for ignoring the meaningless SIGBUSs */
-# ifdef BROKEN_EXCEPTION_HANDLING
- {
- struct sigaction sa, oldsa;
- sa.sa_handler = (SIG_HNDLR_PTR)GC_darwin_sigbus;
- sigemptyset(&sa.sa_mask);
- sa.sa_flags = SA_RESTART|SA_SIGINFO;
- if(sigaction(SIGBUS, &sa, &oldsa) < 0)
- ABORT("sigaction");
- if ((SIG_HNDLR_PTR)oldsa.sa_handler != SIG_DFL) {
- if (GC_print_stats == VERBOSE)
- GC_err_printf("Replaced other SIGBUS handler\n");
- }
- }
-# endif /* BROKEN_EXCEPTION_HANDLING */
-}
-
-/* The source code for Apple's GDB was used as a reference for the exception
- forwarding code. This code is similar to be GDB code only because there is
- only one way to do it. */
-STATIC kern_return_t GC_forward_exception(mach_port_t thread, mach_port_t task,
- exception_type_t exception,
- exception_data_t data,
- mach_msg_type_number_t data_count)
-{
- unsigned int i;
- kern_return_t r;
- mach_port_t port;
- exception_behavior_t behavior;
- thread_state_flavor_t flavor;
-
- thread_state_data_t thread_state;
- mach_msg_type_number_t thread_state_count = THREAD_STATE_MAX;
-
- for(i=0; i < GC_old_exc_ports.count; i++)
- if(GC_old_exc_ports.masks[i] & (1 << exception))
- break;
- if(i==GC_old_exc_ports.count)
- ABORT("No handler for exception!");
-
- port = GC_old_exc_ports.ports[i];
- behavior = GC_old_exc_ports.behaviors[i];
- flavor = GC_old_exc_ports.flavors[i];
-
- if(behavior == EXCEPTION_STATE || behavior == EXCEPTION_STATE_IDENTITY) {
- r = thread_get_state(thread, flavor, thread_state, &thread_state_count);
- if(r != KERN_SUCCESS)
- ABORT("thread_get_state failed in forward_exception");
- }
-
- switch(behavior) {
- case EXCEPTION_STATE:
- r = exception_raise_state(port, thread, task, exception, data, data_count,
- &flavor, thread_state, thread_state_count,
- thread_state, &thread_state_count);
- break;
- case EXCEPTION_STATE_IDENTITY:
- r = exception_raise_state_identity(port, thread, task, exception, data,
- data_count, &flavor, thread_state,
- thread_state_count, thread_state,
- &thread_state_count);
- break;
- /* case EXCEPTION_DEFAULT: */ /* default signal handlers */
- default: /* user-supplied signal handlers */
- r = exception_raise(port, thread, task, exception, data, data_count);
- }
-
- if(behavior == EXCEPTION_STATE || behavior == EXCEPTION_STATE_IDENTITY) {
- r = thread_set_state(thread, flavor, thread_state, thread_state_count);
- if(r != KERN_SUCCESS)
- ABORT("thread_set_state failed in forward_exception");
- }
-
- return r;
-}
-
-#define FWD() GC_forward_exception(thread, task, exception, code, code_count)
-
-/* This violates the namespace rules but there isn't anything that can be done
- about it. The exception handling stuff is hard coded to call this. */
-kern_return_t
-catch_exception_raise(mach_port_t exception_port, mach_port_t thread,
- mach_port_t task, exception_type_t exception,
- exception_data_t code, mach_msg_type_number_t code_count)
-{
- kern_return_t r;
- char *addr;
- struct hblk *h;
- unsigned int i;
-# if defined(POWERPC)
-# if CPP_WORDSZ == 32
- thread_state_flavor_t flavor = PPC_EXCEPTION_STATE;
- mach_msg_type_number_t exc_state_count = PPC_EXCEPTION_STATE_COUNT;
- ppc_exception_state_t exc_state;
-# else
- thread_state_flavor_t flavor = PPC_EXCEPTION_STATE64;
- mach_msg_type_number_t exc_state_count = PPC_EXCEPTION_STATE64_COUNT;
- ppc_exception_state64_t exc_state;
-# endif
-# elif defined(I386) || defined(X86_64)
-# if CPP_WORDSZ == 32
- thread_state_flavor_t flavor = x86_EXCEPTION_STATE32;
- mach_msg_type_number_t exc_state_count = x86_EXCEPTION_STATE32_COUNT;
- x86_exception_state32_t exc_state;
-# else
- thread_state_flavor_t flavor = x86_EXCEPTION_STATE64;
- mach_msg_type_number_t exc_state_count = x86_EXCEPTION_STATE64_COUNT;
- x86_exception_state64_t exc_state;
-# endif
-# else
-# error FIXME for non-ppc/x86 darwin
-# endif
-
-
- if(exception != EXC_BAD_ACCESS || code[0] != KERN_PROTECTION_FAILURE) {
-# ifdef DEBUG_EXCEPTION_HANDLING
- /* We aren't interested, pass it on to the old handler */
- GC_printf("Exception: 0x%x Code: 0x%x 0x%x in catch....\n", exception,
- code_count > 0 ? code[0] : -1, code_count > 1 ? code[1] : -1);
-# endif
- return FWD();
- }
-
- r = thread_get_state(thread, flavor, (natural_t*)&exc_state,
- &exc_state_count);
- if(r != KERN_SUCCESS) {
- /* The thread is supposed to be suspended while the exception handler
- is called. This shouldn't fail. */
-# ifdef BROKEN_EXCEPTION_HANDLING
- GC_err_printf("thread_get_state failed in catch_exception_raise\n");
- return KERN_SUCCESS;
-# else
- ABORT("thread_get_state failed in catch_exception_raise");
-# endif
- }
-
- /* This is the address that caused the fault */
-# if defined(POWERPC)
- addr = (char*) exc_state. THREAD_FLD(dar);
-# elif defined (I386) || defined (X86_64)
- addr = (char*) exc_state. THREAD_FLD(faultvaddr);
-# else
-# error FIXME for non POWERPC/I386
-# endif
-
- if((HDR(addr)) == 0) {
- /* Ugh... just like the SIGBUS problem above, it seems we get a bogus
- KERN_PROTECTION_FAILURE every once and a while. We wait till we get
- a bunch in a row before doing anything about it. If a "real" fault
- ever occurs it'll just keep faulting over and over and we'll hit
- the limit pretty quickly. */
-# ifdef BROKEN_EXCEPTION_HANDLING
- static char *last_fault;
- static int last_fault_count;
-
- if(addr != last_fault) {
- last_fault = addr;
- last_fault_count = 0;
- }
- if(++last_fault_count < 32) {
- if(last_fault_count == 1)
- WARN("Ignoring KERN_PROTECTION_FAILURE at %p\n", addr);
- return KERN_SUCCESS;
- }
-
- GC_err_printf("Unexpected KERN_PROTECTION_FAILURE at %p\n",addr);
- /* Can't pass it along to the signal handler because that is
- ignoring SIGBUS signals. We also shouldn't call ABORT here as
- signals don't always work too well from the exception handler. */
- GC_err_printf("Aborting\n");
- exit(EXIT_FAILURE);
-# else /* BROKEN_EXCEPTION_HANDLING */
- /* Pass it along to the next exception handler
- (which should call SIGBUS/SIGSEGV) */
- return FWD();
-# endif /* !BROKEN_EXCEPTION_HANDLING */
- }
-
-# ifdef BROKEN_EXCEPTION_HANDLING
- /* Reset the number of consecutive SIGBUSs */
- GC_sigbus_count = 0;
-# endif
-
- if(GC_mprotect_state == GC_MP_NORMAL) { /* common case */
- h = (struct hblk*)((word)addr & ~(GC_page_size-1));
- UNPROTECT(h, GC_page_size);
- for (i = 0; i < divHBLKSZ(GC_page_size); i++) {
- register int index = PHT_HASH(h+i);
- async_set_pht_entry_from_index(GC_dirty_pages, index);
- }
- } else if(GC_mprotect_state == GC_MP_DISCARDING) {
- /* Lie to the thread for now. No sense UNPROTECT()ing the memory
- when we're just going to PROTECT() it again later. The thread
- will just fault again once it resumes */
- } else {
- /* Shouldn't happen, i don't think */
- GC_printf("KERN_PROTECTION_FAILURE while world is stopped\n");
- return FWD();
- }
- return KERN_SUCCESS;
-}
-#undef FWD
-
-/* These should never be called, but just in case... */
-kern_return_t
-catch_exception_raise_state(mach_port_name_t exception_port, int exception,
- exception_data_t code,
- mach_msg_type_number_t codeCnt, int flavor,
- thread_state_t old_state, int old_stateCnt,
- thread_state_t new_state, int new_stateCnt)
-{
- ABORT("catch_exception_raise_state");
- return(KERN_INVALID_ARGUMENT);
-}
-
-kern_return_t
-catch_exception_raise_state_identity(mach_port_name_t exception_port,
- mach_port_t thread, mach_port_t task,
- int exception, exception_data_t code,
- mach_msg_type_number_t codeCnt, int flavor,
- thread_state_t old_state, int old_stateCnt,
- thread_state_t new_state, int new_stateCnt)
-{
- ABORT("catch_exception_raise_state_identity");
- return(KERN_INVALID_ARGUMENT);
-}
-
-#endif /* DARWIN && MPROTECT_VDB */
-
-# ifndef HAVE_INCREMENTAL_PROTECTION_NEEDS
- GC_API int GC_CALL GC_incremental_protection_needs(void)
- {
- return GC_PROTECTS_NONE;
- }
-# endif /* !HAVE_INCREMENTAL_PROTECTION_NEEDS */
-
-#ifdef ECOS
- /* Undo sbrk() redirection. */
-# undef sbrk
-#endif
-
-/*
- * Call stack save code for debugging.
- * Should probably be in mach_dep.c, but that requires reorganization.
- */
-
-/* I suspect the following works for most X86 *nix variants, so */
-/* long as the frame pointer is explicitly stored. In the case of gcc, */
-/* compiler flags (e.g. -fomit-frame-pointer) determine whether it is. */
-#if defined(I386) && defined(LINUX) && defined(SAVE_CALL_CHAIN)
-# include <features.h>
-
- struct frame {
- struct frame *fr_savfp;
- long fr_savpc;
- long fr_arg[NARGS]; /* All the arguments go here. */
- };
-#endif
-
-#if defined(SPARC)
-# if defined(LINUX)
-# include <features.h>
-
- struct frame {
- long fr_local[8];
- long fr_arg[6];
- struct frame *fr_savfp;
- long fr_savpc;
-# ifndef __arch64__
- char *fr_stret;
-# endif
- long fr_argd[6];
- long fr_argx[0];
- };
-# elif defined (DRSNX)
-# include <sys/sparc/frame.h>
-# elif defined(OPENBSD)
-# include <frame.h>
-# elif defined(FREEBSD) || defined(NETBSD)
-# include <machine/frame.h>
-# else
-# include <sys/frame.h>
-# endif
-# if NARGS > 6
-# error We only know how to to get the first 6 arguments
-# endif
-#endif /* SPARC */
-
-#ifdef NEED_CALLINFO
-/* Fill in the pc and argument information for up to NFRAMES of my */
-/* callers. Ignore my frame and my callers frame. */
-
-#ifdef LINUX
-# include <unistd.h>
-#endif
-
-#endif /* NEED_CALLINFO */
-
-#if defined(GC_HAVE_BUILTIN_BACKTRACE)
-# ifdef _MSC_VER
-# include "private/msvc_dbg.h"
-# else
-# include <execinfo.h>
-# endif
-#endif
-
-#ifdef SAVE_CALL_CHAIN
-
-#if NARGS == 0 && NFRAMES % 2 == 0 /* No padding */ \
- && defined(GC_HAVE_BUILTIN_BACKTRACE)
-
-#ifdef REDIRECT_MALLOC
- /* Deal with possible malloc calls in backtrace by omitting */
- /* the infinitely recursing backtrace. */
-# ifdef THREADS
- __thread /* If your compiler doesn't understand this */
- /* you could use something like pthread_getspecific. */
-# endif
- GC_in_save_callers = FALSE;
-#endif
-
-GC_INNER void GC_save_callers(struct callinfo info[NFRAMES])
-{
- void * tmp_info[NFRAMES + 1];
- int npcs, i;
-# define IGNORE_FRAMES 1
-
- /* We retrieve NFRAMES+1 pc values, but discard the first, since it */
- /* points to our own frame. */
-# ifdef REDIRECT_MALLOC
- if (GC_in_save_callers) {
- info[0].ci_pc = (word)(&GC_save_callers);
- for (i = 1; i < NFRAMES; ++i) info[i].ci_pc = 0;
- return;
- }
- GC_in_save_callers = TRUE;
-# endif
- GC_STATIC_ASSERT(sizeof(struct callinfo) == sizeof(void *));
- npcs = backtrace((void **)tmp_info, NFRAMES + IGNORE_FRAMES);
- BCOPY(tmp_info+IGNORE_FRAMES, info, (npcs - IGNORE_FRAMES) * sizeof(void *));
- for (i = npcs - IGNORE_FRAMES; i < NFRAMES; ++i) info[i].ci_pc = 0;
-# ifdef REDIRECT_MALLOC
- GC_in_save_callers = FALSE;
-# endif
-}
-
-#else /* No builtin backtrace; do it ourselves */
-
-#if (defined(OPENBSD) || defined(NETBSD) || defined(FREEBSD)) && defined(SPARC)
-# define FR_SAVFP fr_fp
-# define FR_SAVPC fr_pc
-#else
-# define FR_SAVFP fr_savfp
-# define FR_SAVPC fr_savpc
-#endif
-
-#if defined(SPARC) && (defined(__arch64__) || defined(__sparcv9))
-# define BIAS 2047
-#else
-# define BIAS 0
-#endif
-
-GC_INNER void GC_save_callers(struct callinfo info[NFRAMES])
-{
- struct frame *frame;
- struct frame *fp;
- int nframes = 0;
-# ifdef I386
- /* We assume this is turned on only with gcc as the compiler. */
- asm("movl %%ebp,%0" : "=r"(frame));
- fp = frame;
-# else
- frame = (struct frame *)GC_save_regs_in_stack();
- fp = (struct frame *)((long) frame -> FR_SAVFP + BIAS);
-#endif
-
- for (; (!(fp HOTTER_THAN frame) && !(GC_stackbottom HOTTER_THAN (ptr_t)fp)
- && (nframes < NFRAMES));
- fp = (struct frame *)((long) fp -> FR_SAVFP + BIAS), nframes++) {
- register int i;
-
- info[nframes].ci_pc = fp->FR_SAVPC;
-# if NARGS > 0
- for (i = 0; i < NARGS; i++) {
- info[nframes].ci_arg[i] = ~(fp->fr_arg[i]);
- }
-# endif /* NARGS > 0 */
- }
- if (nframes < NFRAMES) info[nframes].ci_pc = 0;
-}
-
-#endif /* No builtin backtrace */
-
-#endif /* SAVE_CALL_CHAIN */
-
-#ifdef NEED_CALLINFO
-
-/* Print info to stderr. We do NOT hold the allocation lock */
-GC_INNER void GC_print_callers(struct callinfo info[NFRAMES])
-{
- int i;
- static int reentry_count = 0;
- GC_bool stop = FALSE;
-
- /* FIXME: This should probably use a different lock, so that we */
- /* become callable with or without the allocation lock. */
- LOCK();
- ++reentry_count;
- UNLOCK();
-
-# if NFRAMES == 1
- GC_err_printf("\tCaller at allocation:\n");
-# else
- GC_err_printf("\tCall chain at allocation:\n");
-# endif
- for (i = 0; i < NFRAMES && !stop; i++) {
- if (info[i].ci_pc == 0) break;
-# if NARGS > 0
- {
- int j;
-
- GC_err_printf("\t\targs: ");
- for (j = 0; j < NARGS; j++) {
- if (j != 0) GC_err_printf(", ");
- GC_err_printf("%d (0x%X)", ~(info[i].ci_arg[j]),
- ~(info[i].ci_arg[j]));
- }
- GC_err_printf("\n");
- }
-# endif
- if (reentry_count > 1) {
- /* We were called during an allocation during */
- /* a previous GC_print_callers call; punt. */
- GC_err_printf("\t\t##PC##= 0x%lx\n", info[i].ci_pc);
- continue;
- }
- {
-# ifdef LINUX
- FILE *pipe;
-# endif
-# if defined(GC_HAVE_BUILTIN_BACKTRACE) \
- && !defined(GC_BACKTRACE_SYMBOLS_BROKEN)
- char **sym_name =
- backtrace_symbols((void **)(&(info[i].ci_pc)), 1);
- char *name = sym_name[0];
-# else
- char buf[40];
- char *name = buf;
- sprintf(buf, "##PC##= 0x%lx", info[i].ci_pc);
-# endif
-# if defined(LINUX) && !defined(SMALL_CONFIG)
- /* Try for a line number. */
- {
-# define EXE_SZ 100
- static char exe_name[EXE_SZ];
-# define CMD_SZ 200
- char cmd_buf[CMD_SZ];
-# define RESULT_SZ 200
- static char result_buf[RESULT_SZ];
- size_t result_len;
- char *old_preload;
-# define PRELOAD_SZ 200
- char preload_buf[PRELOAD_SZ];
- static GC_bool found_exe_name = FALSE;
- static GC_bool will_fail = FALSE;
- int ret_code;
- /* Try to get it via a hairy and expensive scheme. */
- /* First we get the name of the executable: */
- if (will_fail) goto out;
- if (!found_exe_name) {
- ret_code = readlink("/proc/self/exe", exe_name, EXE_SZ);
- if (ret_code < 0 || ret_code >= EXE_SZ
- || exe_name[0] != '/') {
- will_fail = TRUE; /* Don't try again. */
- goto out;
- }
- exe_name[ret_code] = '\0';
- found_exe_name = TRUE;
- }
- /* Then we use popen to start addr2line -e <exe> <addr> */
- /* There are faster ways to do this, but hopefully this */
- /* isn't time critical. */
- sprintf(cmd_buf, "/usr/bin/addr2line -f -e %s 0x%lx", exe_name,
- (unsigned long)info[i].ci_pc);
- old_preload = GETENV("LD_PRELOAD");
- if (0 != old_preload) {
- if (strlen (old_preload) >= PRELOAD_SZ) {
- will_fail = TRUE;
- goto out;
- }
- strcpy (preload_buf, old_preload);
- unsetenv ("LD_PRELOAD");
- }
- pipe = popen(cmd_buf, "r");
- if (0 != old_preload
- && 0 != setenv ("LD_PRELOAD", preload_buf, 0)) {
- WARN("Failed to reset LD_PRELOAD\n", 0);
- }
- if (pipe == NULL
- || (result_len = fread(result_buf, 1, RESULT_SZ - 1, pipe))
- == 0) {
- if (pipe != NULL) pclose(pipe);
- will_fail = TRUE;
- goto out;
- }
- if (result_buf[result_len - 1] == '\n') --result_len;
- result_buf[result_len] = 0;
- if (result_buf[0] == '?'
- || (result_buf[result_len-2] == ':'
- && result_buf[result_len-1] == '0')) {
- pclose(pipe);
- goto out;
- }
- /* Get rid of embedded newline, if any. Test for "main" */
- {
- char * nl = strchr(result_buf, '\n');
- if (nl != NULL && nl < result_buf + result_len) {
- *nl = ':';
- }
- if (strncmp(result_buf, "main", nl - result_buf) == 0) {
- stop = TRUE;
- }
- }
- if (result_len < RESULT_SZ - 25) {
- /* Add in hex address */
- sprintf(result_buf + result_len, " [0x%lx]",
- (unsigned long)info[i].ci_pc);
- }
- name = result_buf;
- pclose(pipe);
- out:;
- }
-# endif /* LINUX */
- GC_err_printf("\t\t%s\n", name);
-# if defined(GC_HAVE_BUILTIN_BACKTRACE) \
- && !defined(GC_BACKTRACE_SYMBOLS_BROKEN)
- free(sym_name); /* May call GC_free; that's OK */
-# endif
- }
- }
- LOCK();
- --reentry_count;
- UNLOCK();
-}
-
-#endif /* NEED_CALLINFO */
-
-#if defined(LINUX) && defined(__ELF__) && !defined(SMALL_CONFIG)
-
-/* Dump /proc/self/maps to GC_stderr, to enable looking up names for
- addresses in FIND_LEAK output. */
-
-static word dump_maps(char *maps)
-{
- GC_err_write(maps, strlen(maps));
- return 1;
-}
-
-void GC_print_address_map(void)
-{
- GC_err_printf("---------- Begin address map ----------\n");
- dump_maps(GC_get_maps());
- GC_err_printf("---------- End address map ----------\n");
-}
-
-#endif
projects / l4.git / blobdiff