From 199648ff3729b733fe35fc510bc1e6334206fb30 Mon Sep 17 00:00:00 2001
From: goldsimon <goldsimon>
Date: Tue, 9 Oct 2007 19:59:56 +0000
Subject: [PATCH] Changed initialization: many init functions are not needed
 any more since we now rely on the compiler initializing global and static
 variables to zero!

---
 CHANGELOG                   |  5 +++++
 doc/contrib.txt             |  3 ++-
 src/api/sockets.c           |  6 +++---
 src/api/tcpip.c             | 10 +++++-----
 src/core/ipv4/igmp.c        |  2 --
 src/core/ipv4/ip.c          | 11 -----------
 src/core/ipv4/ip_frag.c     |  8 --------
 src/core/mem.c              |  1 -
 src/core/netif.c            |  9 ---------
 src/core/raw.c              | 11 +----------
 src/core/snmp/mib_structs.c |  2 +-
 src/core/snmp/msg_in.c      |  2 +-
 src/core/stats.c            |  5 -----
 src/core/tcp.c              | 19 -------------------
 src/core/udp.c              | 11 +----------
 src/include/ipv4/lwip/ip.h  |  2 +-
 src/include/lwip/netif.h    |  3 +--
 src/include/lwip/raw.h      |  2 +-
 src/include/lwip/stats.h    |  2 +-
 src/include/lwip/tcp.h      |  3 +--
 src/include/lwip/udp.h      |  3 ++-
 src/include/netif/etharp.h  |  2 +-
 src/netif/etharp.c          | 30 ++++++++----------------------
 23 files changed, 35 insertions(+), 117 deletions(-)

diff --git a/CHANGELOG b/CHANGELOG
index 36c55d5a..005ccbe8 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -19,6 +19,11 @@ HISTORY
 
   ++ New features:
 
+  2007-10-08 Simon Goldschmidt
+  * many files: Changed initialization: many init functions are not needed any
+    more since we now rely on the compiler initializing global and static
+    variables to zero!
+
   2007-10-06 Simon Goldschmidt
   * ip_frag.c, memp.c, mib2.c, ip_frag.h, memp_std.h, opt.h: Changed IP_REASSEMBLY
     to enqueue the received pbufs so that multiple packets can be reassembled
diff --git a/doc/contrib.txt b/doc/contrib.txt
index 7c99b9be..39596fca 100644
--- a/doc/contrib.txt
+++ b/doc/contrib.txt
@@ -21,7 +21,8 @@ features of Savannah help us not lose users' input.
 6. one space and no newline before opening curly braces of a block.
 7. closing curly brace on a single line.
 8. spaces surrounding assignment and comparisons.
-9. use current source code style as further reference.
+9. don't initialize static and/or global variables to zero, the compiler takes care of that.
+10. use current source code style as further reference.
 
 2.2 Source code documentation style:
 
diff --git a/src/api/sockets.c b/src/api/sockets.c
index 60919435..b9eebd44 100644
--- a/src/api/sockets.c
+++ b/src/api/sockets.c
@@ -86,10 +86,10 @@ struct lwip_setgetsockopt_data {
 };
 
 static struct lwip_socket sockets[NUM_SOCKETS];
-static struct lwip_select_cb *select_cb_list = 0;
+static struct lwip_select_cb *select_cb_list;
 
-static sys_sem_t socksem = 0;
-static sys_sem_t selectsem = 0;
+static sys_sem_t socksem;
+static sys_sem_t selectsem;
 
 static void event_callback(struct netconn *conn, enum netconn_evt evt, u16_t len);
 static void lwip_getsockopt_internal(void *arg);
diff --git a/src/api/tcpip.c b/src/api/tcpip.c
index e79fabe1..939402f7 100644
--- a/src/api/tcpip.c
+++ b/src/api/tcpip.c
@@ -54,18 +54,18 @@
 #include "netif/ppp_oe.h"
 
 /* global variables */
-static void (* tcpip_init_done)(void *arg) = NULL;
-static void *tcpip_init_done_arg           = NULL;
-static sys_mbox_t mbox                     = SYS_MBOX_NULL;
+static void (* tcpip_init_done)(void *arg);
+static void *tcpip_init_done_arg;
+static sys_mbox_t mbox = SYS_MBOX_NULL;
 
 #if LWIP_TCPIP_CORE_LOCKING
 /** The global semaphore to lock the stack. */
-sys_sem_t lock_tcpip_core = 0;
+sys_sem_t lock_tcpip_core;
 #endif /* LWIP_TCPIP_CORE_LOCKING */
 
 #if LWIP_TCP
 /* global variable that shows if the tcp timer is currently scheduled or not */
-static int tcpip_tcp_timer_active = 0;
+static int tcpip_tcp_timer_active;
 
 /**
  * Timer callback function that calls tcp_tmr() and reschedules itself.
diff --git a/src/core/ipv4/igmp.c b/src/core/ipv4/igmp.c
index c8370b7b..7040a3af 100644
--- a/src/core/ipv4/igmp.c
+++ b/src/core/ipv4/igmp.c
@@ -113,8 +113,6 @@ igmp_init(void)
 
   IP4_ADDR(&allsystems, 224, 0, 0, 1);
   IP4_ADDR(&allrouters, 224, 0, 0, 2);
-
-  igmp_group_list = NULL;
 }
 
 #ifdef LWIP_DEBUG
diff --git a/src/core/ipv4/ip.c b/src/core/ipv4/ip.c
index 9980cbc8..2b0ccdec 100644
--- a/src/core/ipv4/ip.c
+++ b/src/core/ipv4/ip.c
@@ -55,17 +55,6 @@
 #include "lwip/stats.h"
 #include "arch/perf.h"
 
-/**
- * Initializes the IP layer.
- */
-void
-ip_init(void)
-{
-#if IP_REASSEMBLY
-  ip_reass_init();
-#endif
-}
-
 /**
  * Finds the appropriate network interface for a given IP address. It
  * searches the list of network interfaces linearly. A match is found
diff --git a/src/core/ipv4/ip_frag.c b/src/core/ipv4/ip_frag.c
index 3adb3de2..ffec6b80 100644
--- a/src/core/ipv4/ip_frag.c
+++ b/src/core/ipv4/ip_frag.c
@@ -85,14 +85,6 @@ static u16_t ip_reass_pbufcount;
 /* function prototypes */
 static void dequeue_packet(struct ip_reassdata *ipr, struct ip_reassdata *prev);
 
-/**
- * Initializes IP reassembly states.
- */
-void
-ip_reass_init(void)
-{
-}
-
 /**
  * Reassembly timer base function
  * for both NO_SYS == 0 and 1 (!).
diff --git a/src/core/mem.c b/src/core/mem.c
index afb4a52f..01f78eda 100644
--- a/src/core/mem.c
+++ b/src/core/mem.c
@@ -206,7 +206,6 @@ mem_init(void)
     (SIZEOF_STRUCT_MEM & (MEM_ALIGNMENT-1)) == 0);
 
   /* align the heap */
-  memset(ram_heap, 0, sizeof(ram_heap));
   ram = LWIP_MEM_ALIGN(ram_heap);
   /* initialize the start of the heap */
   mem = (struct mem *)ram;
diff --git a/src/core/netif.c b/src/core/netif.c
index 9c9da2b1..a31992d2 100644
--- a/src/core/netif.c
+++ b/src/core/netif.c
@@ -61,15 +61,6 @@
 struct netif *netif_list = NULL;
 struct netif *netif_default = NULL;
 
-/**
- * Initialize this module
- */
-void
-netif_init(void)
-{
-  netif_list = netif_default = NULL;
-}
-
 /**
  * Add a network interface to the list of lwIP netifs.
  *
diff --git a/src/core/raw.c b/src/core/raw.c
index 421c4933..4ee3fc0e 100644
--- a/src/core/raw.c
+++ b/src/core/raw.c
@@ -55,16 +55,7 @@
 #include <string.h>
 
 /** The list of RAW PCBs */
-static struct raw_pcb *raw_pcbs = NULL;
-
-/**
- * Initialize this module
- */
-void
-raw_init(void)
-{
-  raw_pcbs = NULL;
-}
+static struct raw_pcb *raw_pcbs;
 
 /**
  * Determine if in incoming IP packet is covered by a RAW PCB
diff --git a/src/core/snmp/mib_structs.c b/src/core/snmp/mib_structs.c
index ba78f857..af8994ed 100644
--- a/src/core/snmp/mib_structs.c
+++ b/src/core/snmp/mib_structs.c
@@ -53,7 +53,7 @@ struct nse
   /** right child next level */
   u8_t r_nl;
 };
-static u8_t node_stack_cnt = 0;
+static u8_t node_stack_cnt;
 static struct nse node_stack[NODE_STACK_SIZE];
 
 /**
diff --git a/src/core/snmp/msg_in.c b/src/core/snmp/msg_in.c
index ab8b5216..e09bac18 100644
--- a/src/core/snmp/msg_in.c
+++ b/src/core/snmp/msg_in.c
@@ -56,7 +56,7 @@ const char snmp_publiccommunity[7] = "public";
 /* statically allocated buffers for SNMP_CONCURRENT_REQUESTS */
 struct snmp_msg_pstat msg_input_list[SNMP_CONCURRENT_REQUESTS];
 /* UDP Protocol Control Block */
-struct udp_pcb *snmp1_pcb = NULL;
+struct udp_pcb *snmp1_pcb;
 
 static void snmp_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16_t port);
 static err_t snmp_pdu_header_check(struct pbuf *p, u16_t ofs, u16_t pdu_len, u16_t *ofs_ret, struct snmp_msg_pstat *m_stat);
diff --git a/src/core/stats.c b/src/core/stats.c
index 640baab5..e693d869 100644
--- a/src/core/stats.c
+++ b/src/core/stats.c
@@ -48,11 +48,6 @@
 
 struct stats_ lwip_stats;
 
-void
-stats_init(void)
-{
-  memset(&lwip_stats, 0, sizeof(struct stats_));
-}
 #if LWIP_STATS_DISPLAY
 void
 stats_display_proto(struct stats_proto *proto, char *name)
diff --git a/src/core/tcp.c b/src/core/tcp.c
index a7ce7394..a28b2890 100644
--- a/src/core/tcp.c
+++ b/src/core/tcp.c
@@ -74,25 +74,6 @@ struct tcp_pcb *tcp_tmp_pcb;
 static u8_t tcp_timer;
 static u16_t tcp_new_port(void);
 
-/**
- * Initializes the TCP layer.
- */
-void
-tcp_init(void)
-{
-  /* Clear globals. */
-  tcp_bound_pcbs = NULL;
-  tcp_listen_pcbs.listen_pcbs = NULL;
-  tcp_active_pcbs = NULL;
-  tcp_tw_pcbs = NULL;
-  tcp_tmp_pcb = NULL;
-  
-  /* initialize timer */
-  tcp_ticks = 0;
-  tcp_timer = 0;
-  
-}
-
 /**
  * Called periodically to dispatch TCP timers.
  *
diff --git a/src/core/udp.c b/src/core/udp.c
index 437cdb1f..f78d55b0 100644
--- a/src/core/udp.c
+++ b/src/core/udp.c
@@ -65,16 +65,7 @@
 
 /* The list of UDP PCBs */
 /* exported in udp.h (was static) */
-struct udp_pcb *udp_pcbs = NULL;
-
-/**
- * Initialize the UDP module
- */
-void
-udp_init(void)
-{
-  udp_pcbs = NULL;
-}
+struct udp_pcb *udp_pcbs;
 
 /**
  * Process an incoming UDP datagram.
diff --git a/src/include/ipv4/lwip/ip.h b/src/include/ipv4/lwip/ip.h
index e61ac319..3b760f00 100644
--- a/src/include/ipv4/lwip/ip.h
+++ b/src/include/ipv4/lwip/ip.h
@@ -43,7 +43,7 @@
 extern "C" {
 #endif
 
-void ip_init(void);
+#define ip_init() /* Compatibility define, not init needed. */
 struct netif *ip_route(struct ip_addr *dest);
 err_t ip_input(struct pbuf *p, struct netif *inp);
 err_t ip_output(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
diff --git a/src/include/lwip/netif.h b/src/include/lwip/netif.h
index 81dd338b..19c38087 100644
--- a/src/include/lwip/netif.h
+++ b/src/include/lwip/netif.h
@@ -192,8 +192,7 @@ extern struct netif *netif_list;
 /** The default network interface. */
 extern struct netif *netif_default;
 
-/* netif_init() must be called first. */
-void netif_init(void);
+#define netif_init() /* Compatibility define, not init needed. */
 
 struct netif *netif_add(struct netif *netif, struct ip_addr *ipaddr, struct ip_addr *netmask,
       struct ip_addr *gw,
diff --git a/src/include/lwip/raw.h b/src/include/lwip/raw.h
index 56d21b18..5834fc95 100644
--- a/src/include/lwip/raw.h
+++ b/src/include/lwip/raw.h
@@ -85,7 +85,7 @@ err_t            raw_send       (struct raw_pcb *pcb, struct pbuf *p);
 
 /* The following functions are the lower layer interface to RAW. */
 u8_t             raw_input      (struct pbuf *p, struct netif *inp);
-void             raw_init       (void);
+#define raw_init() /* Compatibility define, not init needed. */
 
 #ifdef __cplusplus
 }
diff --git a/src/include/lwip/stats.h b/src/include/lwip/stats.h
index 1dbc0df9..ee319b24 100644
--- a/src/include/lwip/stats.h
+++ b/src/include/lwip/stats.h
@@ -136,7 +136,7 @@ struct stats_ {
 
 extern struct stats_ lwip_stats;
 
-void stats_init(void);
+#define stats_init() /* Compatibility define, not init needed. */
 
 #define STATS_INC(x) ++lwip_stats.x
 #else
diff --git a/src/include/lwip/tcp.h b/src/include/lwip/tcp.h
index ab87ca5b..8e2fc68a 100644
--- a/src/include/lwip/tcp.h
+++ b/src/include/lwip/tcp.h
@@ -52,8 +52,7 @@ struct tcp_pcb;
 /* Functions for interfacing with TCP: */
 
 /* Lower layer interface to TCP: */
-void             tcp_init    (void);  /* Must be called first to
-                                         initialize TCP. */
+#define tcp_init() /* Compatibility define, not init needed. */
 void             tcp_tmr     (void);  /* Must be called every
                                          TCP_TMR_INTERVAL
                                          ms. (Typically 250 ms). */
diff --git a/src/include/lwip/udp.h b/src/include/lwip/udp.h
index cd0f33cd..89d1f5e7 100644
--- a/src/include/lwip/udp.h
+++ b/src/include/lwip/udp.h
@@ -130,7 +130,8 @@ err_t            udp_send       (struct udp_pcb *pcb, struct pbuf *p);
 
 /* The following functions are the lower layer interface to UDP. */
 void             udp_input      (struct pbuf *p, struct netif *inp);
-void             udp_init       (void);
+
+#define udp_init() /* Compatibility define, not init needed. */
 
 #if UDP_DEBUG
 void udp_debug_print(struct udp_hdr *udphdr);
diff --git a/src/include/netif/etharp.h b/src/include/netif/etharp.h
index e5d9e15d..2b76823b 100644
--- a/src/include/netif/etharp.h
+++ b/src/include/netif/etharp.h
@@ -141,7 +141,7 @@ struct etharp_q_entry {
 };
 #endif /* ARP_QUEUEING */
 
-void etharp_init(void);
+#define etharp_init() /* Compatibility define, not init needed. */
 void etharp_tmr(void);
 s8_t etharp_find_addr(struct netif *netif, struct ip_addr *ipaddr,
          struct eth_addr **eth_ret, struct ip_addr **ip_ret);
diff --git a/src/netif/etharp.c b/src/netif/etharp.c
index 77fd2eeb..63b458cc 100644
--- a/src/netif/etharp.c
+++ b/src/netif/etharp.c
@@ -103,7 +103,7 @@ const struct eth_addr ethbroadcast = {{0xff,0xff,0xff,0xff,0xff,0xff}};
 const struct eth_addr ethzero = {{0,0,0,0,0,0}};
 static struct etharp_entry arp_table[ARP_TABLE_SIZE];
 #if !LWIP_NETIF_HWADDRHINT
-static u8_t etharp_cached_entry = 0;
+static u8_t etharp_cached_entry;
 #endif
 
 /**
@@ -122,29 +122,15 @@ static s8_t find_entry(struct ip_addr *ipaddr, u8_t flags);
 
 static err_t update_arp_entry(struct netif *netif, struct ip_addr *ipaddr, struct eth_addr *ethaddr, u8_t flags);
 
-/**
- * Initializes ARP module.
- */
-void
-etharp_init(void)
-{
-  u8_t i;
-
-  LWIP_ASSERT("ARP_TABLE_SIZE < 0x80 (due to s8_t limitation)",
-              (ARP_TABLE_SIZE < 0x80));
 
-  /* clear ARP entries */
-  for (i = 0; i < ARP_TABLE_SIZE; ++i) {
-    /* use memset to be safe (intialize all future variables to 0) */
-    memset(&arp_table[i], 0, sizeof(struct etharp_entry));
-    arp_table[i].state = ETHARP_STATE_EMPTY;
-#if ARP_QUEUEING
-    arp_table[i].q = NULL;
+/* Some checks, instead of etharp_init(): */
+#if ETHARP_STATE_EMPTY != 0
+#error ETHARP_STATE_EMPTY must be 0 to ensure correct initialization value!
 #endif
-    arp_table[i].ctime = 0;
-    arp_table[i].netif = NULL;
-  }
-}
+#if (LWIP_ARP && (ARP_TABLE_SIZE > 0x7f))
+  #error "If you want to use ARP, ARP_TABLE_SIZE must fit in an s8_t, so, you have to reduce it in your lwipopts.h"
+#endif
+
 
 #if ARP_QUEUEING
 /**
-- 
2.39.2