diffcore-pickaxe.c

   1 /*
   2  * Copyright (C) 2005 Junio C Hamano
   3  */
   4 #include "cache.h"
   5 #include "diff.h"
   6 #include "diffcore.h"
   7
   8 static unsigned int contains(struct diff_filespec *one,
   9                              const char *needle, unsigned long len,
  10                              regex_t *regexp)
  11 {
  12         unsigned int cnt;
  13         unsigned long sz;
  14         const char *data;
  15         if (diff_populate_filespec(one, 0))
  16                 return 0;
  17         if (!len)
  18                 return 0;
  19
  20         sz = one->size;
  21         data = one->data;
  22         cnt = 0;
  23
  24         if (regexp) {
  25                 regmatch_t regmatch;
  26                 int flags = 0;
  27
  28                 while (*data && !regexec(regexp, data, 1, &regmatch, flags)) {
  29                         flags |= REG_NOTBOL;
  30                         data += regmatch.rm_so;
  31                         if (*data) data++;
  32                         cnt++;
  33                 }
  34
  35         } else { /* Classic exact string match */
  36                 while (sz) {
  37                         const char *found = memmem(data, sz, needle, len);
  38                         if (!found)
  39                                 break;
  40                         sz -= found - data + len;
  41                         data = found + len;
  42                         cnt++;
  43                 }
  44         }
  45         diff_free_filespec_data(one);
  46         return cnt;
  47 }
  48
  49 void diffcore_pickaxe(const char *needle, int opts)
  50 {
  51         struct diff_queue_struct *q = &diff_queued_diff;
  52         unsigned long len = strlen(needle);
  53         int i, has_changes;
  54         regex_t regex, *regexp = NULL;
  55         struct diff_queue_struct outq;
  56         outq.queue = NULL;
  57         outq.nr = outq.alloc = 0;
  58
  59         if (opts & DIFF_PICKAXE_REGEX) {
  60                 int err;
  61                 err = regcomp(&regex, needle, REG_EXTENDED | REG_NEWLINE);
  62                 if (err) {
  63                         /* The POSIX.2 people are surely sick */
  64                         char errbuf[1024];
  65                         regerror(err, &regex, errbuf, 1024);
  66                         regfree(&regex);
  67                         die("invalid pickaxe regex: %s", errbuf);
  68                 }
  69                 regexp = &regex;
  70         }
  71
  72         if (opts & DIFF_PICKAXE_ALL) {
  73                 /* Showing the whole changeset if needle exists */
  74                 for (i = has_changes = 0; !has_changes && i < q->nr; i++) {
  75                         struct diff_filepair *p = q->queue[i];
  76                         if (!DIFF_FILE_VALID(p->one)) {
  77                                 if (!DIFF_FILE_VALID(p->two))
  78                                         continue; /* ignore unmerged */
  79                                 /* created */
  80                                 if (contains(p->two, needle, len, regexp))
  81                                         has_changes++;
  82                         }
  83                         else if (!DIFF_FILE_VALID(p->two)) {
  84                                 if (contains(p->one, needle, len, regexp))
  85                                         has_changes++;
  86                         }
  87                         else if (!diff_unmodified_pair(p) &&
  88                                  contains(p->one, needle, len, regexp) !=
  89                                  contains(p->two, needle, len, regexp))
  90                                 has_changes++;
  91                 }
  92                 if (has_changes)
  93                         return; /* not munge the queue */
  94
  95                 /* otherwise we will clear the whole queue
  96                  * by copying the empty outq at the end of this
  97                  * function, but first clear the current entries
  98                  * in the queue.
  99                  */
 100                 for (i = 0; i < q->nr; i++)
 101                         diff_free_filepair(q->queue[i]);
 102         }
 103         else
 104                 /* Showing only the filepairs that has the needle */
 105                 for (i = 0; i < q->nr; i++) {
 106                         struct diff_filepair *p = q->queue[i];
 107                         has_changes = 0;
 108                         if (!DIFF_FILE_VALID(p->one)) {
 109                                 if (!DIFF_FILE_VALID(p->two))
 110                                         ; /* ignore unmerged */
 111                                 /* created */
 112                                 else if (contains(p->two, needle, len, regexp))
 113                                         has_changes = 1;
 114                         }
 115                         else if (!DIFF_FILE_VALID(p->two)) {
 116                                 if (contains(p->one, needle, len, regexp))
 117                                         has_changes = 1;
 118                         }
 119                         else if (!diff_unmodified_pair(p) &&
 120                                  contains(p->one, needle, len, regexp) !=
 121                                  contains(p->two, needle, len, regexp))
 122                                 has_changes = 1;
 123
 124                         if (has_changes)
 125                                 diff_q(&outq, p);
 126                         else
 127                                 diff_free_filepair(p);
 128                 }
 129
 130         if (opts & DIFF_PICKAXE_REGEX) {
 131                 regfree(&regex);
 132         }
 133
 134         free(q->queue);
 135         *q = outq;
 136         return;
 137 }