init: simpler handling of leading dash in commands

function                                             old     new   delta
init_exec                                            233     219     -14

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/init/init.c b/init/init.c
index 0a0d503..a2cc3b5 100644 (file)
--- a/init/init.c
+++ b/init/init.c
@@ -401,20 +401,22 @@ static void init_exec(const char *command)
        char buf[COMMAND_SIZE + 6];  /* COMMAND_SIZE+strlen("exec ")+1 */
        int dash = (command[0] == '-' /* maybe? && command[1] == '/' */);
 
+       command += dash;
+
        /* See if any special /bin/sh requiring characters are present */
        if (strpbrk(command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
-               strcpy(buf, "exec ");
-               strcpy(buf + 5, command + dash); /* excluding "-" */
+               sprintf(buf, "exec %s", command); /* excluding "-" */
                /* NB: LIBBB_DEFAULT_LOGIN_SHELL define has leading dash */
                cmd[0] = (char*)(LIBBB_DEFAULT_LOGIN_SHELL + !dash);
                cmd[1] = (char*)"-c";
                cmd[2] = buf;
                cmd[3] = NULL;
+               command = LIBBB_DEFAULT_LOGIN_SHELL + 1;
        } else {
                /* Convert command (char*) into cmd (char**, one word per string) */
                char *word, *next;
                int i = 0;
-               next = strcpy(buf, command); /* including "-" */
+               next = strcpy(buf, command - dash); /* command including "-" */
                while ((word = strsep(&next, " \t")) != NULL) {
                        if (*word != '\0') { /* not two spaces/tabs together? */
                                cmd[i] = word;
@@ -425,14 +427,14 @@ static void init_exec(const char *command)
        }
        /* If we saw leading "-", it is interactive shell.
         * Try harder to give it a controlling tty.
-        * And skip "-" in actual exec call. */
-       if (dash) {
+        */
+       if (ENABLE_FEATURE_INIT_SCTTY && dash) {
                /* _Attempt_ to make stdin a controlling tty. */
-               if (ENABLE_FEATURE_INIT_SCTTY)
-                       ioctl(STDIN_FILENO, TIOCSCTTY, 0 /*only try, don't steal*/);
+               ioctl(STDIN_FILENO, TIOCSCTTY, 0 /*only try, don't steal*/);
        }
-       BB_EXECVP(cmd[0] + dash, cmd);
-       message(L_LOG | L_CONSOLE, "can't run '%s': %s", cmd[0], strerror(errno));
+       /* Here command never contains the dash, cmd[0] might */
+       BB_EXECVP(command, cmd);
+       message(L_LOG | L_CONSOLE, "can't run '%s': %s", command, strerror(errno));
        /* returns if execvp fails */
 }
 

diff --git a/shell/ash.c b/shell/ash.c
index 5671a52..6f03ac1 100644 (file)
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -13063,7 +13063,7 @@ int ash_main(int argc UNUSED_PARAM, char **argv)
                }
        }
 #endif
-       if (/* argv[0] && */ argv[0][0] == '-')
+       if (argv[0] && argv[0][0] == '-')
                isloginsh = 1;
        if (isloginsh) {
                state = 1;