hush: move msh/lash config into hush.c, no code changes

[oweals/busybox.git] / libbb / vfork_daemon_rexec.c

diff --git a/libbb/vfork_daemon_rexec.c b/libbb/vfork_daemon_rexec.c
index da0dc03e58b236f38c360a383f75e30aea185bb1..5c2c529c972a6099725243b8c99bfcddb8ff97ee 100644 (file)
--- a/libbb/vfork_daemon_rexec.c
+++ b/libbb/vfork_daemon_rexec.c
@@ -15,7 +15,6 @@
  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  */
 
-#include <paths.h>
 #include "busybox.h" /* uses applet tables */
 
 /* This does a fork/exec in one call, using vfork().  Returns PID of new child,
@@ -26,7 +25,7 @@ pid_t FAST_FUNC spawn(char **argv)
        volatile int failed;
        pid_t pid;
 
-// Ain't it a good place to fflush(NULL)?
+       fflush_all();
 
        /* Be nice to nommu machines. */
        failed = 0;
@@ -42,6 +41,8 @@ pid_t FAST_FUNC spawn(char **argv)
                 * (but don't run atexit() stuff, which would screw up parent.)
                 */
                failed = errno;
+               /* mount, for example, does not want the message */
+               /*bb_perror_msg("can't execute '%s'", argv[0]);*/
                _exit(111);
        }
        /* parent */
@@ -66,40 +67,6 @@ pid_t FAST_FUNC xspawn(char **argv)
        return pid;
 }
 
-int FAST_FUNC safe_waitpid(int pid, int *wstat, int options)
-{
-       int r;
-
-       do
-               r = waitpid(pid, wstat, options);
-       while ((r == -1) && (errno == EINTR));
-       return r;
-}
-
-int FAST_FUNC wait_any_nohang(int *wstat)
-{
-       return safe_waitpid(-1, wstat, WNOHANG);
-}
-
-// Wait for the specified child PID to exit, returning child's error return.
-int FAST_FUNC wait4pid(int pid)
-{
-       int status;
-
-       if (pid <= 0) {
-               /*errno = ECHILD; -- wrong. */
-               /* we expect errno to be already set from failed [v]fork/exec */
-               return -1;
-       }
-       if (safe_waitpid(pid, &status, 0) == -1)
-               return -1;
-       if (WIFEXITED(status))
-               return WEXITSTATUS(status);
-       if (WIFSIGNALED(status))
-               return WTERMSIG(status) + 1000;
-       return 0;
-}
-
 #if ENABLE_FEATURE_PREFER_APPLETS
 void FAST_FUNC save_nofork_data(struct nofork_save_area *save)
 {
@@ -125,6 +92,7 @@ int FAST_FUNC run_nofork_applet_prime(struct nofork_save_area *old, int applet_n
        int rc, argc;
 
        applet_name = APPLET_NAME(applet_no);
+
        xfunc_error_retval = EXIT_FAILURE;
 
        /* Special flag for xfunc_die(). If xfunc will "die"
@@ -132,7 +100,30 @@ int FAST_FUNC run_nofork_applet_prime(struct nofork_save_area *old, int applet_n
         * die_sleep and longjmp here instead. */
        die_sleep = -1;
 
-       /* option_mask32 = 0; - not needed */
+       /* In case getopt() or getopt32() was already called:
+        * reset the libc getopt() function, which keeps internal state.
+        *
+        * BSD-derived getopt() functions require that optind be set to 1 in
+        * order to reset getopt() state.  This used to be generally accepted
+        * way of resetting getopt().  However, glibc's getopt()
+        * has additional getopt() state beyond optind, and requires that
+        * optind be set to zero to reset its state.  So the unfortunate state of
+        * affairs is that BSD-derived versions of getopt() misbehave if
+        * optind is set to 0 in order to reset getopt(), and glibc's getopt()
+        * will core dump if optind is set 1 in order to reset getopt().
+        *
+        * More modern versions of BSD require that optreset be set to 1 in
+        * order to reset getopt().  Sigh.  Standards, anyone?
+        */
+#ifdef __GLIBC__
+       optind = 0;
+#else /* BSD style */
+       optind = 1;
+       /* optreset = 1; */
+#endif
+       /* optarg = NULL; opterr = 1; optopt = 63; - do we need this too? */
+       /* (values above are what they initialized to in glibc and uclibc) */
+       /* option_mask32 = 0; - not needed, no applet depends on it being 0 */
 
        argc = 1;
        while (argv[argc])
@@ -161,8 +152,16 @@ int FAST_FUNC run_nofork_applet_prime(struct nofork_save_area *old, int applet_n
                        rc = 0;
        }
 
-       /* Restoring globals */
+       /* Restoring some globals */
        restore_nofork_data(old);
+
+       /* Other globals can be simply reset to defaults */
+#ifdef __GLIBC__
+       optind = 0;
+#else /* BSD style */
+       optind = 1;
+#endif
+
        return rc & 0xff; /* don't confuse people with "exitcodes" >255 */
 }
 
@@ -216,38 +215,21 @@ void FAST_FUNC re_exec(char **argv)
         * "we have (already) re-execed, don't do it again" flag */
        argv[0][0] |= 0x80;
        execv(bb_busybox_exec_path, argv);
-       bb_perror_msg_and_die("exec %s", bb_busybox_exec_path);
+       bb_perror_msg_and_die("can't execute '%s'", bb_busybox_exec_path);
 }
 
-void FAST_FUNC forkexit_or_rexec(char **argv)
+pid_t FAST_FUNC fork_or_rexec(char **argv)
 {
        pid_t pid;
        /* Maybe we are already re-execed and come here again? */
        if (re_execed)
-               return;
-
-       pid = vfork();
-       if (pid < 0) /* wtf? */
-               bb_perror_msg_and_die("vfork");
+               return 0;
+       pid = xvfork();
        if (pid) /* parent */
-               exit(EXIT_SUCCESS);
+               return pid;
        /* child - re-exec ourself */
        re_exec(argv);
 }
-#else
-/* Dance around (void)...*/
-#undef forkexit_or_rexec
-void FAST_FUNC forkexit_or_rexec(void)
-{
-       pid_t pid;
-       pid = fork();
-       if (pid < 0) /* wtf? */
-               bb_perror_msg_and_die("fork");
-       if (pid) /* parent */
-               exit(EXIT_SUCCESS);
-       /* child */
-}
-#define forkexit_or_rexec(argv) forkexit_or_rexec()
 #endif
 
 /* Due to a #define in libbb.h on MMU systems we actually have 1 argument -
@@ -278,7 +260,8 @@ void FAST_FUNC bb_daemonize_or_rexec(int flags, char **argv)
                fd = dup(fd); /* have 0,1,2 open at least to /dev/null */
 
        if (!(flags & DAEMON_ONLY_SANITIZE)) {
-               forkexit_or_rexec(argv);
+               if (fork_or_rexec(argv))
+                       exit(EXIT_SUCCESS); /* parent */
                /* if daemonizing, make sure we detach from stdio & ctty */
                setsid();
                dup2(fd, 0);