Merge branch 'busybox' into merge

1 files changed, 41 insertions, 27 deletions

diff --git a/init/init.c b/init/init.c
index 15aad474f..edb5be696 100644
--- a/init/init.c
+++ b/init/init.c
@@ -140,12 +140,11 @@
  * not fully functional init by switching it on! */
 #define DEBUG_INIT 0
 
-#define COMMAND_SIZE      256
 #define CONSOLE_NAME_SIZE 32
 
 /* Default sysinit script. */
 #ifndef INIT_SCRIPT
-#define INIT_SCRIPT  "/etc/init.d/rcS"
+# define INIT_SCRIPT  "/etc/init.d/rcS"
 #endif
 
 /* Each type of actions can appear many times. They will be
@@ -195,7 +194,7 @@ struct init_action {
         pid_t pid;
         uint8_t action_type;
         char terminal[CONSOLE_NAME_SIZE];
-        char command[COMMAND_SIZE];
+        char command[1];
 };
 
 static struct init_action *init_action_list = NULL;
@@ -398,7 +397,7 @@ static void reset_sighandlers_and_unblock_sigs(void)
 }
 
 /* Wrapper around exec:
- * Takes string (max COMMAND_SIZE chars).
+ * Takes string.
  * If chars like '>' detected, execs '[-]/bin/sh -c "exec ......."'.
  * Otherwise splits words on whitespace, deals with leading dash,
  * and uses plain exec().
@@ -406,10 +405,15 @@ static void reset_sighandlers_and_unblock_sigs(void)
  */
 static void init_exec(const char *command)
 {
-        char *cmd[COMMAND_SIZE / 2];
-        char buf[COMMAND_SIZE + 6];  /* COMMAND_SIZE+strlen("exec ")+1 */
-        int dash = (command[0] == '-' /* maybe? && command[1] == '/' */);
-
+        /* +8 allows to write VLA sizes below more efficiently: */
+        unsigned command_size = strlen(command) + 8;
+        /* strlen(command) + strlen("exec ")+1: */
+        char buf[command_size];
+        /* strlen(command) / 2 + 4: */
+        char *cmd[command_size / 2];
+        int dash;
+
+        dash = (command[0] == '-' /* maybe? && command[1] == '/' */);
         command += dash;
 
         /* See if any special /bin/sh requiring characters are present */
@@ -626,21 +630,21 @@ static void new_init_action(uint8_t action_type, const char *command, const char
                 nextp = &a->next;
         }
 
-        a = xzalloc(sizeof(*a));
+        a = xzalloc(sizeof(*a) + strlen(command));
 
         /* Append to the end of the list */
  append:
         *nextp = a;
         a->action_type = action_type;
-        safe_strncpy(a->command, command, sizeof(a->command));
+        strcpy(a->command, command);
         safe_strncpy(a->terminal, cons, sizeof(a->terminal));
-        dbg_message(L_LOG | L_CONSOLE, "command='%s' action=%d tty='%s'\n",
+        dbg_message(L_LOG | L_CONSOLE, "command='%s' action=%x tty='%s'\n",
                 a->command, a->action_type, a->terminal);
 }
 
 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
  * then parse_inittab() simply adds in some default
- * actions(i.e., runs INIT_SCRIPT and then starts a pair
+ * actions (i.e., runs INIT_SCRIPT and then starts a pair
  * of "askfirst" shells).  If CONFIG_FEATURE_USE_INITTAB
  * _is_ defined, but /etc/inittab is missing, this
  * results in the same set of default behaviors.
@@ -655,23 +659,22 @@ static void parse_inittab(void)
 #endif
         {
                 /* No inittab file - set up some default behavior */
-                /* Reboot on Ctrl-Alt-Del */
-                new_init_action(CTRLALTDEL, "reboot", "");
-                /* Umount all filesystems on halt/reboot */
-                new_init_action(SHUTDOWN, "umount -a -r", "");
-                /* Swapoff on halt/reboot */
-                if (ENABLE_SWAPONOFF)
-                        new_init_action(SHUTDOWN, "swapoff -a", "");
-                /* Prepare to restart init when a QUIT is received */
-                new_init_action(RESTART, "init", "");
+                /* Sysinit */
+                new_init_action(SYSINIT, INIT_SCRIPT, "");
                 /* Askfirst shell on tty1-4 */
                 new_init_action(ASKFIRST, bb_default_login_shell, "");
 //TODO: VC_1 instead of ""? "" is console -> ctty problems -> angry users
                 new_init_action(ASKFIRST, bb_default_login_shell, VC_2);
                 new_init_action(ASKFIRST, bb_default_login_shell, VC_3);
                 new_init_action(ASKFIRST, bb_default_login_shell, VC_4);
-                /* sysinit */
-                new_init_action(SYSINIT, INIT_SCRIPT, "");
+                /* Reboot on Ctrl-Alt-Del */
+                new_init_action(CTRLALTDEL, "reboot", "");
+                /* Umount all filesystems on halt/reboot */
+                new_init_action(SHUTDOWN, "umount -a -r", "");
+                /* Swapoff on halt/reboot */
+                new_init_action(SHUTDOWN, "swapoff -a", "");
+                /* Restart init when a QUIT is received */
+                new_init_action(RESTART, "init", "");
                 return;
         }
 
@@ -931,10 +934,17 @@ static void reload_inittab(void)
 
         /* Remove stale entries and SYSINIT entries.
          * We never rerun SYSINIT entries anyway,
-         * removing them too saves a few bytes */
+         * removing them too saves a few bytes
+         */
         nextp = &init_action_list;
         while ((a = *nextp) != NULL) {
-                if ((a->action_type & ~SYSINIT) == 0) {
+                /*
+                 * Why pid == 0 check?
+                 * Process can be removed from inittab and added *later*.
+                 * If we delete its entry but process still runs,
+                 * duplicate is spawned when the entry is re-added.
+                 */
+                if ((a->action_type & ~SYSINIT) == 0 && a->pid == 0) {
                         *nextp = a->next;
                         free(a);
                 } else {
@@ -1058,10 +1068,13 @@ int init_main(int argc UNUSED_PARAM, char **argv)
         message(L_CONSOLE | L_LOG, "init started: %s", bb_banner);
 #endif
 
+#if 0
+/* It's 2013, does anyone really still depend on this? */
+/* If you do, consider adding swapon to sysinot actions then! */
 /* struct sysinfo is linux-specific */
-#ifdef __linux__
+# ifdef __linux__
         /* Make sure there is enough memory to do something useful. */
-        if (ENABLE_SWAPONOFF) {
+        /*if (ENABLE_SWAPONOFF) - WRONG: we may have non-bbox swapon*/ {
                 struct sysinfo info;
 
                 if (sysinfo(&info) == 0
@@ -1075,6 +1088,7 @@ int init_main(int argc UNUSED_PARAM, char **argv)
                         run_actions(SYSINIT);   /* wait and removing */
                 }
         }
+# endif
 #endif
 
         /* Check if we are supposed to be in single user mode */