noexec: consolidate code

function                                             old     new   delta
run_noexec_applet_and_exit                             -      61     +61
find_applet_by_name                                  128     124      -4
run_applet_no_and_exit                               441     434      -7
tryexec                                              169     152     -17
pseudo_exec_argv                                     338     321     -17
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/6 up/down: 61/-48)             Total: 13 bytes

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

5 files changed, 26 insertions, 34 deletions

diff --git a/include/libbb.h b/include/libbb.h
index e4a19ac04..3f3e033fe 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -1112,9 +1112,10 @@ int wait_for_exitstatus(pid_t pid) FAST_FUNC;
 int spawn_and_wait(char **argv) FAST_FUNC;
 /* Does NOT check that applet is NOFORK, just blindly runs it */
 int run_nofork_applet(int applet_no, char **argv) FAST_FUNC;
+void run_noexec_applet_and_exit(int a, const char *name, char **argv) NORETURN FAST_FUNC;
 #ifndef BUILD_INDIVIDUAL
-extern int find_applet_by_name(const char *name) FAST_FUNC;
-extern void run_applet_no_and_exit(int a, const char *name, char **argv) NORETURN FAST_FUNC;
+int find_applet_by_name(const char *name) FAST_FUNC;
+void run_applet_no_and_exit(int a, const char *name, char **argv) NORETURN FAST_FUNC;
 #endif
 #if defined(__linux__)
 void set_task_comm(const char *comm) FAST_FUNC;
diff --git a/libbb/appletlib.c b/libbb/appletlib.c
index ce259446b..5b84920a4 100644
--- a/libbb/appletlib.c
+++ b/libbb/appletlib.c
@@ -924,8 +924,6 @@ void FAST_FUNC run_applet_no_and_exit(int applet_no, const char *name, char **ar
 {
         int argc = string_array_len(argv);
 
-        /* Reinit some shared global data */
-        xfunc_error_retval = EXIT_FAILURE;
         /*
          * We do not use argv[0]: do not want to repeat massaging of
          * "-/sbin/halt" -> "halt", for example.
diff --git a/libbb/vfork_daemon_rexec.c b/libbb/vfork_daemon_rexec.c
index 9d3cb9d54..a349459f0 100644
--- a/libbb/vfork_daemon_rexec.c
+++ b/libbb/vfork_daemon_rexec.c
@@ -158,6 +158,26 @@ int FAST_FUNC run_nofork_applet(int applet_no, char **argv)
 }
 #endif /* FEATURE_PREFER_APPLETS || FEATURE_SH_NOFORK */
 
+#if (NUM_APPLETS > 1) && (ENABLE_FEATURE_PREFER_APPLETS || ENABLE_FEATURE_SH_STANDALONE)
+void FAST_FUNC run_noexec_applet_and_exit(int a, const char *name, char **argv)
+{
+        /* reset some state and run without execing */
+        /* msg_eol = "\n"; - no caller needs this reinited yet */
+        logmode = LOGMODE_STDIO;
+        xfunc_error_retval = EXIT_FAILURE;
+        die_func = NULL;
+        GETOPT_RESET();
+
+//TODO: think pidof, pgrep, pkill!
+//set_task_comm() makes our pidof find NOEXECs (e.g. "yes >/dev/null"),
+//but one from procps-ng-3.3.10 needs more!
+//Rewrite /proc/PID/cmdline? (need to save argv0 and length at init for this to work!)
+        set_task_comm(name);
+        /* xfunc_error_retval and applet_name are init by: */
+        run_applet_no_and_exit(a, name, argv);
+}
+#endif
+
 int FAST_FUNC spawn_and_wait(char **argv)
 {
         int rc;
@@ -175,22 +195,7 @@ int FAST_FUNC spawn_and_wait(char **argv)
                                 return wait4pid(rc);
 
                         /* child */
-                        /* reset some state and run without execing */
-                        GETOPT_RESET();
-
-                        /* msg_eol = "\n"; - no caller needs this reinited yet */
-                        logmode = LOGMODE_STDIO;
-                        /* die_func = NULL; - needed if the caller is a shell,
-                         * init, or a NOFORK applet. But none of those call us
-                         * as of yet (and that should probably always stay true).
-                         */
-//TODO: think pidof, pgrep, pkill!
-//set_task_comm() makes our pidof find NOEXECs (e.g. "yes >/dev/null"),
-//but one from procps-ng-3.3.10 needs more!
-//Rewrite /proc/PID/cmdline? (need to save argv0 and length at init for this to work!)
-                        set_task_comm(argv[0]);
-                        /* xfunc_error_retval and applet_name are init by: */
-                        run_applet_no_and_exit(a, argv[0], argv);
+                        run_noexec_applet_and_exit(a, argv[0], argv);
                 }
 # endif
         }
diff --git a/shell/ash.c b/shell/ash.c
index bedd27b0d..6dc1cfef7 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -7803,13 +7803,7 @@ tryexec(IF_FEATURE_SH_STANDALONE(int applet_no,) const char *cmd, char **argv, c
                         while (*envp)
                                 putenv(*envp++);
                         popredir(/*drop:*/ 1);
-                        GETOPT_RESET();
-//TODO: think pidof, pgrep, pkill!
-//set_task_comm() makes our pidof find NOEXECs (e.g. "yes >/dev/null"),
-//but one from procps-ng-3.3.10 needs more!
-//Rewrite /proc/PID/cmdline? (need to save argv0 and length at init for this to work!)
-                        set_task_comm(argv[0]);
-                        run_applet_no_and_exit(applet_no, cmd, argv);
+                        run_noexec_applet_and_exit(applet_no, cmd, argv);
                 }
                 /* re-exec ourselves with the new arguments */
                 execve(bb_busybox_exec_path, argv, envp);
diff --git a/shell/hush.c b/shell/hush.c
index b890107a2..8dc531657 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -7386,14 +7386,8 @@ static NOINLINE void pseudo_exec_argv(nommu_save_t *nommu_save,
 //FIXME: should also close saved redir fds
                                 /* Without this, "rm -i FILE" can't be ^C'ed: */
                                 switch_off_special_sigs(G.special_sig_mask);
-                                GETOPT_RESET();
-//TODO: think pidof, pgrep, pkill!
-//set_task_comm() makes our pidof find NOEXECs (e.g. "yes >/dev/null"),
-//but one from procps-ng-3.3.10 needs more!
-//Rewrite /proc/PID/cmdline? (need to save argv0 and length at init for this to work!)
-                                set_task_comm(argv[0]);
                                 debug_printf_exec("running applet '%s'\n", argv[0]);
-                                run_applet_no_and_exit(a, argv[0], argv);
+                                run_noexec_applet_and_exit(a, argv[0], argv);
                         }
 # endif
                         /* Re-exec ourselves */