init: fix bug 1111: restart actions were not splitting words:

::restart:/sbin/rc restart
resulted in:
exec of '/sbin/rc restart' failed: No such file or directory

2 files changed, 96 insertions, 108 deletions

diff --git a/init/Config.in b/init/Config.in
index 4c5610246..f525abc8a 100644
--- a/init/Config.in
+++ b/init/Config.in
@@ -47,15 +47,18 @@ config FEATURE_KILL_DELAY
           wrong process!)
 
 config FEATURE_INIT_SCTTY
-        bool "Support running commands with a controlling-tty"
+        bool "Run commands with leading dash with controlling tty"
         default n
         depends on INIT
         help
-          If this option is enabled a command starting with hyphen (-)
-          is run in its own session (setsid(2)) and possibly with a
-          controlling tty (TIOCSCTTY).  This is not the traditional init
-          behavour, but is often what you want in an embedded system where
-          the console is only accessed during development or for maintenance.
+          If this option is enabled, init will try to give a controlling
+          tty to any command which has leading hyphen (often it's "-/bin/sh").
+          More precisely, init will do "ioctl(STDIN_FILENO, TIOCSCTTY, 0)".
+          If device attached to STDIN_FILENO can be a ctty but is not yet
+          a ctty for other session, it will become this process' ctty.
+          This is not the traditional init behavour, but is often what you want
+          in an embedded system where the console is only accessed during
+          development or for maintenance.
           NB: using cttyhack applet may work better.
 
 config FEATURE_INIT_SYSLOG
diff --git a/init/init.c b/init/init.c
index 080c5b3af..8d706fe1f 100644
--- a/init/init.c
+++ b/init/init.c
@@ -14,7 +14,7 @@
 #include <paths.h>
 #include <sys/reboot.h>
 
-#define INIT_BUFFS_SIZE 256
+#define COMMAND_SIZE 256
 #define CONSOLE_NAME_SIZE 32
 #define MAXENV  16              /* Number of env. vars */
 
@@ -55,9 +55,9 @@
 struct init_action {
         struct init_action *next;
         pid_t pid;
-        uint8_t action;
+        uint8_t action_type;
         char terminal[CONSOLE_NAME_SIZE];
-        char command[INIT_BUFFS_SIZE];
+        char command[COMMAND_SIZE];
 };
 
 /* Static variables */
@@ -294,14 +294,57 @@ static void open_stdio_to_tty(const char* tty_name, int exit_on_failure)
         set_sane_term();
 }
 
+/* wrapper around exec:
+ * takes string (max COMMAND_SIZE chars)
+ * runs [-]/bin/sh -c "exec ......." if '>' etc detected.
+ * otherwise splits words on whitespace and deals with leading dash.
+ */
+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] == '-');
+
+        /* See if any special /bin/sh requiring characters are present */
+        if (strpbrk(command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
+                strcpy(buf, "exec ");
+                strcpy(buf + 5, command + dash); /* excluding "-" */
+                /* LIBBB_DEFAULT_LOGIN_SHELL has leading dash */
+                cmd[0] = (char*)(LIBBB_DEFAULT_LOGIN_SHELL + !dash);
+                cmd[1] = (char*)"-c";
+                cmd[2] = buf;
+                cmd[3] = NULL;
+        } else {
+                /* Convert command (char*) into cmd (char**, one word per string) */
+                char *word, *next;
+                int i = 0;
+                next = strcpy(buf, command); /* including "-" */
+                while ((word = strsep(&next, " \t")) != NULL) {
+                        if (*word != '\0') { /* not two spaces/tabs together? */
+                                cmd[i] = word;
+                                i++;
+                        }
+                }
+                cmd[i] = NULL;
+        }
+        /* If we saw leading "-", it is interactive shell.
+         * Try harder to give it a controlling tty.
+         * And skip "-" in actual exec call. */
+        if (dash) {
+                /* _Attempt_ to make stdin a controlling tty. */
+                if (ENABLE_FEATURE_INIT_SCTTY)
+                        ioctl(STDIN_FILENO, TIOCSCTTY, 0 /*only try, don't steal*/);
+        }
+        BB_EXECVP(cmd[0] + dash, cmd);
+        message(L_LOG | L_CONSOLE, "Cannot run '%s': %s",
+                        cmd[0], strerror(errno));
+        /* returns if execvp fails */
+}
+
 /* Used only by run_actions */
 static pid_t run(const struct init_action *a)
 {
-        int i;
         pid_t pid;
-        char *s, *tmpCmd, *cmdpath;
-        char *cmd[INIT_BUFFS_SIZE];
-        char buf[INIT_BUFFS_SIZE + 6];  /* INIT_BUFFS_SIZE+strlen("exec ")+1 */
         sigset_t nmask, omask;
 
         /* Block sigchild while forking (why?) */
@@ -341,7 +384,7 @@ static pid_t run(const struct init_action *a)
 #ifdef BUT_RUN_ACTIONS_ALREADY_DOES_WAITING
         /* If the init Action requires us to wait, then force the
          * supplied terminal to be the controlling tty. */
-        if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
+        if (a->action_type & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
                 /* Now fork off another process to just hang around */
                 pid = fork();
                 if (pid < 0) {
@@ -381,58 +424,7 @@ static pid_t run(const struct init_action *a)
                 /* Child - fall though to actually execute things */
         }
 #endif
-
-        /* See if any special /bin/sh requiring characters are present */
-        if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
-                cmd[0] = (char*)DEFAULT_SHELL;
-                cmd[1] = (char*)"-c";
-                cmd[2] = strcat(strcpy(buf, "exec "), a->command);
-                cmd[3] = NULL;
-        } else {
-                /* Convert command (char*) into cmd (char**, one word per string) */
-                strcpy(buf, a->command);
-                s = buf;
-                for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) {
-                        if (*tmpCmd != '\0') {
-                                cmd[i] = tmpCmd;
-                                i++;
-                        }
-                }
-                cmd[i] = NULL;
-        }
-
-        cmdpath = cmd[0];
-
-        /*
-         * Interactive shells want to see a dash in argv[0].  This
-         * typically is handled by login, argv will be setup this
-         * way if a dash appears at the front of the command path
-         * (like "-/bin/sh").
-         */
-        if (*cmdpath == '-') {
-                /* skip over the dash */
-                ++cmdpath;
-
-#ifdef WHY_WE_DO_THIS_SHELL_MUST_HANDLE_THIS_ITSELF
-                /* find the last component in the command pathname */
-                s = bb_get_last_path_component_nostrip(cmdpath);
-                /* make a new argv[0] */
-                cmd[0] = malloc(strlen(s) + 2);
-                if (cmd[0] == NULL) {
-                        message(L_LOG | L_CONSOLE, bb_msg_memory_exhausted);
-                        cmd[0] = cmdpath;
-                } else {
-                        cmd[0][0] = '-';
-                        strcpy(cmd[0] + 1, s);
-                }
-#endif
-
-                /* _Attempt_ to make stdin a controlling tty. */
-                if (ENABLE_FEATURE_INIT_SCTTY)
-                        ioctl(0, TIOCSCTTY, 0 /*only try, don't steal*/);
-        }
-
-        if (a->action & ASKFIRST) {
+        if (a->action_type & ASKFIRST) {
                 static const char press_enter[] ALIGN1 =
 #ifdef CUSTOMIZED_BANNER
 #include CUSTOMIZED_BANNER
@@ -449,58 +441,54 @@ static pid_t run(const struct init_action *a)
                  */
                 messageD(L_LOG, "waiting for enter to start '%s'"
                                         "(pid %d, tty '%s')\n",
-                                  cmdpath, getpid(), a->terminal);
+                                a->command, getpid(), a->terminal);
                 full_write(1, press_enter, sizeof(press_enter) - 1);
                 while (safe_read(0, &c, 1) == 1 && c != '\n')
                         continue;
         }
 
-        /* Log the process name and args */
-        message(L_LOG, "starting pid %d, tty '%s': '%s'",
-                          getpid(), a->terminal, cmdpath);
-
         if (ENABLE_FEATURE_INIT_COREDUMPS) {
                 struct stat sb;
                 if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
                         struct rlimit limit;
-
                         limit.rlim_cur = RLIM_INFINITY;
                         limit.rlim_max = RLIM_INFINITY;
                         setrlimit(RLIMIT_CORE, &limit);
                 }
         }
 
+        /* Log the process name and args */
+        message(L_LOG, "starting pid %d, tty '%s': '%s'",
+                          getpid(), a->terminal, a->command);
+
         /* Now run it.  The new program will take over this PID,
          * so nothing further in init.c should be run. */
-        BB_EXECVP(cmdpath, cmd);
-
+        init_exec(a->command);
         /* We're still here?  Some error happened. */
-        message(L_LOG | L_CONSOLE, "Cannot run '%s': %s",
-                        cmdpath, strerror(errno));
         _exit(-1);
 }
 
 /* Run all commands of a particular type */
-static void run_actions(int action)
+static void run_actions(int action_type)
 {
         struct init_action *a, *tmp;
 
         for (a = init_action_list; a; a = tmp) {
                 tmp = a->next;
-                if (a->action == action) {
+                if (a->action_type == action_type) {
                         // Pointless: run() will error out if open of device fails.
                         ///* a->terminal of "" means "init's console" */
                         //if (a->terminal[0] && access(a->terminal, R_OK | W_OK)) {
                         //      //message(L_LOG | L_CONSOLE, "Device %s cannot be opened in RW mode", a->terminal /*, strerror(errno)*/);
                         //      delete_init_action(a);
                         //} else
-                        if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
+                        if (a->action_type & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
                                 waitfor(run(a));
                                 delete_init_action(a);
-                        } else if (a->action & ONCE) {
+                        } else if (a->action_type & ONCE) {
                                 run(a);
                                 delete_init_action(a);
-                        } else if (a->action & (RESPAWN | ASKFIRST)) {
+                        } else if (a->action_type & (RESPAWN | ASKFIRST)) {
                                 /* Only run stuff with pid==0.  If they have
                                  * a pid, that means it is still running */
                                 if (a->pid == 0) {
@@ -593,12 +581,11 @@ static void halt_reboot_pwoff(int sig)
  * else (no such action defined) do nothing */
 static void exec_restart_action(int sig ATTRIBUTE_UNUSED)
 {
-        struct init_action *a, *tmp;
+        struct init_action *a;
         sigset_t unblock_signals;
 
-        for (a = init_action_list; a; a = tmp) {
-                tmp = a->next;
-                if (a->action & RESTART) {
+        for (a = init_action_list; a; a = a->next) {
+                if (a->action_type & RESTART) {
                         kill_all_processes();
 
                         /* unblock all signals (blocked in kill_all_processes()) */
@@ -620,10 +607,7 @@ static void exec_restart_action(int sig ATTRIBUTE_UNUSED)
                         open_stdio_to_tty(a->terminal, 0 /* - halt if open fails */);
 
                         messageD(L_CONSOLE | L_LOG, "Trying to re-exec %s", a->command);
-                        BB_EXECLP(a->command, a->command, NULL);
-
-                        message(L_CONSOLE | L_LOG, "Cannot run '%s': %s",
-                                        a->command, strerror(errno));
+                        init_exec(a->command);
                         sleep(2);
                         init_reboot(RB_HALT_SYSTEM);
                         loop_forever();
@@ -654,12 +638,13 @@ static void cont_handler(int sig ATTRIBUTE_UNUSED)
         got_cont = 1;
 }
 
-static void new_init_action(uint8_t action, const char *command, const char *cons)
+static void new_init_action(uint8_t action_type, const char *command, const char *cons)
 {
-        struct init_action *new_action, *a, *last;
+        struct init_action *a, *last;
 
-        if (strcmp(cons, bb_dev_null) == 0 && (action & ASKFIRST))
-                return;
+// Why?
+//      if (strcmp(cons, bb_dev_null) == 0 && (action & ASKFIRST))
+//              return;
 
         /* Append to the end of the list */
         for (a = last = init_action_list; a; a = a->next) {
@@ -668,23 +653,23 @@ static void new_init_action(uint8_t action, const char *command, const char *con
                 if ((strcmp(a->command, command) == 0)
                  && (strcmp(a->terminal, cons) == 0)
                 ) {
-                        a->action = action;
+                        a->action_type = action_type;
                         return;
                 }
                 last = a;
         }
 
-        new_action = xzalloc(sizeof(struct init_action));
+        a = xzalloc(sizeof(*a));
         if (last) {
-                last->next = new_action;
+                last->next = a;
         } else {
-                init_action_list = new_action;
+                init_action_list = a;
         }
-        strcpy(new_action->command, command);
-        new_action->action = action;
-        strcpy(new_action->terminal, cons);
+        a->action_type = action_type;
+        safe_strncpy(a->command, command, sizeof(a->command));
+        safe_strncpy(a->terminal, cons, sizeof(a->terminal));
         messageD(L_LOG | L_CONSOLE, "command='%s' action=%d tty='%s'\n",
-                new_action->command, new_action->action, new_action->terminal);
+                a->command, a->action_type, a->terminal);
 }
 
 static void delete_init_action(struct init_action *action)
@@ -714,7 +699,7 @@ static void delete_init_action(struct init_action *action)
 static void parse_inittab(void)
 {
         FILE *file;
-        char buf[INIT_BUFFS_SIZE];
+        char buf[COMMAND_SIZE];
 
         if (ENABLE_FEATURE_USE_INITTAB)
                 file = fopen(INITTAB, "r");
@@ -743,7 +728,7 @@ static void parse_inittab(void)
                 return;
         }
 
-        while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
+        while (fgets(buf, COMMAND_SIZE, file) != NULL) {
                 static const char actions[] =
                         STR_SYSINIT    "sysinit\0"
                         STR_RESPAWN    "respawn\0"
@@ -810,7 +795,7 @@ static void reload_signal(int sig ATTRIBUTE_UNUSED)
 
         /* disable old entrys */
         for (a = init_action_list; a; a = a->next) {
-                a->action = ONCE;
+                a->action_type = ONCE;
         }
 
         parse_inittab();
@@ -819,7 +804,7 @@ static void reload_signal(int sig ATTRIBUTE_UNUSED)
                 /* Be nice and send SIGTERM first */
                 for (a = init_action_list; a; a = a->next) {
                         pid_t pid = a->pid;
-                        if ((a->action & ONCE) && pid != 0) {
+                        if ((a->action_type & ONCE) && pid != 0) {
                                 kill(pid, SIGTERM);
                         }
                 }
@@ -828,7 +813,7 @@ static void reload_signal(int sig ATTRIBUTE_UNUSED)
                         sleep(CONFIG_FEATURE_KILL_DELAY);
                         for (a = init_action_list; a; a = a->next) {
                                 pid_t pid = a->pid;
-                                if ((a->action & ONCE) && pid != 0) {
+                                if ((a->action_type & ONCE) && pid != 0) {
                                         kill(pid, SIGKILL);
                                 }
                         }
@@ -840,7 +825,7 @@ static void reload_signal(int sig ATTRIBUTE_UNUSED)
         /* remove unused entrys */
         for (a = init_action_list; a; a = tmp) {
                 tmp = a->next;
-                if ((a->action & (ONCE | SYSINIT | WAIT)) && a->pid == 0) {
+                if ((a->action_type & (ONCE | SYSINIT | WAIT)) && a->pid == 0) {
                         delete_init_action(a);
                 }
         }
@@ -998,7 +983,7 @@ int init_main(int argc, char **argv)
                                          * restarted by run_actions() */
                                         a->pid = 0;
                                         message(L_LOG, "process '%s' (pid %d) exited. "
-                                                        "Scheduling it for restart.",
+                                                        "Scheduling for restart.",
                                                         a->command, wpid);
                                 }
                         }