factor out NOFORK/NOEXEC code from find. Use it for xargs too.

4 files changed, 76 insertions, 68 deletions

diff --git a/findutils/find.c b/findutils/find.c
index 7b5a09d56..1a1301b38 100644
--- a/findutils/find.c
+++ b/findutils/find.c
@@ -238,37 +238,19 @@ ACTF(inum)
 ACTF(exec)
 {
         int i, rc;
-        char *argv[ap->exec_argc+1];
+        char *argv[ap->exec_argc + 1];
         for (i = 0; i < ap->exec_argc; i++)
                 argv[i] = subst(ap->exec_argv[i], ap->subst_count[i], fileName);
         argv[i] = NULL; /* terminate the list */
 
-        if (ENABLE_FEATURE_EXEC_PREFER_APPLETS) {
-                const struct BB_applet *a = find_applet_by_name(argv[0]);
-                if (a) {
-                        if (a->nofork) {
-                                rc = a->main(ap->exec_argc, argv);
-                                goto f;
-                        }
-#ifndef BB_NOMMU
-                        if (a->noexec) {
-                                rc = fork();
-                                if (rc) goto w;
-                                current_applet = a;
-                                run_current_applet_and_exit(ap->exec_argc, argv);
-                        }
-#endif
-                }
-        }
-        rc = spawn(argv);
- w:
-        rc = wait4pid(rc);
+        rc = spawn_and_wait(argv);
         if (rc < 0)
                 bb_perror_msg("%s", argv[0]);
- f:
-        for (i = 0; i < ap->exec_argc; i++)
-                free(argv[i]);
-        return rc == 0; /* return 1 if success */
+
+        i = 0;
+        while (argv[i])
+                free(argv[i++]);
+        return rc == 0; /* return 1 if exitcode 0 */
 }
 #endif
 
diff --git a/findutils/xargs.c b/findutils/xargs.c
index ea7c22060..b4dd9f876 100644
--- a/findutils/xargs.c
+++ b/findutils/xargs.c
@@ -48,47 +48,32 @@
    This function has special algorithm.
    Don't use fork and include to main!
 */
-static int xargs_exec(char *const *args)
+static int xargs_exec(char **args)
 {
-        pid_t p;
-        volatile int exec_errno = 0;    /* shared vfork stack */
         int status;
 
-        p = vfork();
-        if (p < 0)
-                bb_perror_msg_and_die("vfork");
-
-        if (p == 0) {
-                /* vfork -- child */
-                BB_EXECVP(args[0], args);
-                exec_errno = errno;     /* set error to shared stack */
-                _exit(1);
-        }
-
-        /* vfork -- parent */
-        while (wait(&status) == (pid_t) -1)
-                if (errno != EINTR)
-                        break;
-        if (exec_errno) {
-                errno = exec_errno;
+        status = spawn_and_wait(args);
+        if (status < 0) {
                 bb_perror_msg("%s", args[0]);
-                return exec_errno == ENOENT ? 127 : 126;
+                return errno == ENOENT ? 127 : 126;
         }
-        if (WEXITSTATUS(status) == 255) {
+        if (status == 255) {
                 bb_error_msg("%s: exited with status 255; aborting", args[0]);
                 return 124;
         }
+/* Huh? I think we won't see this, ever. We don't wait with WUNTRACED!
         if (WIFSTOPPED(status)) {
                 bb_error_msg("%s: stopped by signal %d",
                         args[0], WSTOPSIG(status));
                 return 125;
         }
-        if (WIFSIGNALED(status)) {
+*/
+        if (status >= 1000) {
                 bb_error_msg("%s: terminated by signal %d",
-                        args[0], WTERMSIG(status));
+                        args[0], status - 1000);
                 return 125;
         }
-        if (WEXITSTATUS(status))
+        if (status)
                 return 123;
         return 0;
 }
diff --git a/include/libbb.h b/include/libbb.h
index 4fc5d183f..cec31a7f4 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -269,17 +269,6 @@ char *xrealloc_getcwd_or_warn(char *cwd);
 char *xmalloc_readlink_or_warn(const char *path);
 char *xmalloc_realpath(const char *path);
 
-/* Unlike waitpid, waits ONLY for one process,
- * It's safe to pass negative 'pids' from failed [v]fork -
- * wait4pid will return -1 and ECHILD in errno.
- * IOW: rc = wait4pid(spawn(argv));
- *      if (rc < 0) bb_perror_msg("%s", argv[0]);
- *      if (rc > 0) bb_error_msg("exit code: %d", rc);
- */
-extern int wait4pid(int pid);
-extern int wait_pid(int *wstat, int pid);
-extern int wait_nohang(int *wstat);
-//TODO: signal(sid, f) is the same? then why?
 extern void sig_catch(int,void (*)(int));
 //#define sig_ignore(s) (sig_catch((s), SIG_IGN))
 //#define sig_uncatch(s) (sig_catch((s), SIG_DFL))
@@ -288,10 +277,6 @@ extern void sig_unblock(int);
 /* UNUSED: extern void sig_blocknone(void); */
 extern void sig_pause(void);
 
-#define wait_crashed(w) ((w) & 127)
-#define wait_exitcode(w) ((w) >> 8)
-#define wait_stopsig(w) ((w) >> 8)
-#define wait_stopped(w) (((w) & 127) == 127)
 
 
 void xsetgid(gid_t gid);
@@ -528,6 +513,25 @@ int bb_execvp(const char *file, char *const argv[]);
 /* NOMMU friendy fork+exec */
 pid_t spawn(char **argv);
 pid_t xspawn(char **argv);
+
+/* Unlike waitpid, waits ONLY for one process,
+ * It's safe to pass negative 'pids' from failed [v]fork -
+ * wait4pid will return -1 and ECHILD in errno.
+ * IOW: rc = wait4pid(spawn(argv));
+ *      if (rc < 0) bb_perror_msg("%s", argv[0]);
+ *      if (rc > 0) bb_error_msg("exit code: %d", rc);
+ */
+int wait_pid(int *wstat, int pid);
+int wait_nohang(int *wstat);
+int wait4pid(int pid);
+//TODO: signal(sid, f) is the same? then why?
+#define wait_crashed(w) ((w) & 127)
+#define wait_exitcode(w) ((w) >> 8)
+#define wait_stopsig(w) ((w) >> 8)
+#define wait_stopped(w) (((w) & 127) == 127)
+/* wait4pid(spawn(argv)) + NOFORK/NOEXEC (if configured) */
+int spawn_and_wait(char **argv);
+
 /* Helpers for daemonization.
  *
  * bb_daemonize(flags) = daemonize, does not compile on NOMMU
@@ -573,6 +577,7 @@ void bb_daemonize_or_rexec(int flags, char **argv);
 void bb_sanitize_stdio(void);
 
 
+// TODO: always error out?
 enum { BB_GETOPT_ERROR = 0x80000000 };
 extern const char *opt_complementary;
 #if ENABLE_GETOPT_LONG
diff --git a/libbb/vfork_daemon_rexec.c b/libbb/vfork_daemon_rexec.c
index ff2b0bceb..d25693917 100644
--- a/libbb/vfork_daemon_rexec.c
+++ b/libbb/vfork_daemon_rexec.c
@@ -16,7 +16,7 @@
  */
 
 #include <paths.h>
-#include "libbb.h"
+#include "busybox.h" /* for struct BB_applet */
 
 /* This does a fork/exec in one call, using vfork().  Returns PID of new child,
  * -1 for failure.  Runs argv[0], searching path if that has no / in it. */
@@ -72,7 +72,8 @@ int wait4pid(int pid)
         int status;
 
         if (pid <= 0) {
-                /*errno = ECHILD; -- wrong. we expect errno to be set from failed exec */
+                /*errno = ECHILD; -- wrong. */
+                /* we expect errno to be already set from failed [v]fork/exec */
                 return -1;
         }
         if (waitpid(pid, &status, 0) == -1)
@@ -80,7 +81,7 @@ int wait4pid(int pid)
         if (WIFEXITED(status))
                 return WEXITSTATUS(status);
         if (WIFSIGNALED(status))
-                return WTERMSIG(status) + 10000;
+                return WTERMSIG(status) + 1000;
         return 0;
 }
 
@@ -99,6 +100,41 @@ int wait_pid(int *wstat, int pid)
         return r;
 }
 
+int spawn_and_wait(char **argv)
+{
+        int rc;
+
+        if (ENABLE_FEATURE_EXEC_PREFER_APPLETS) {
+                const struct BB_applet *a = find_applet_by_name(argv[0]);
+                if (a && (a->nofork
+#ifndef BB_NOMMU
+                         || a->noexec /* NOEXEC cannot be used on NOMMU */
+#endif
+                )) {
+                        int argc = 1;
+                        char **pp = argv;
+                        while (*++pp)
+                                argc++;
+#ifdef BB_NOMMU
+                        return a->main(argc, argv);
+#else
+                        if (a->nofork)
+                                return a->main(argc, argv);
+                        /* a->noexec is true */
+                        rc = fork();
+                        if (rc)
+                                goto w;
+                        /* child */
+                        current_applet = a;
+                        run_current_applet_and_exit(argc, argv);
+#endif
+                }
+        }
+        rc = spawn(argv);
+ w:
+        return wait4pid(rc);
+}
+
 #if 0 //ndef BB_NOMMU
 // Die with an error message if we can't daemonize.
 void xdaemon(int nochdir, int noclose)