1 files changed, 134 insertions, 44 deletions

diff --git a/run-command.c b/run-command.c
index 1db8abf984..3914d9c511 100644
--- a/run-command.c
+++ b/run-command.c
@@ -4,6 +4,10 @@
 #include "sigchain.h"
 #include "argv-array.h"
 
+#ifndef SHELL_PATH
+# define SHELL_PATH "/bin/sh"
+#endif
+
 struct child_to_clean {
 	pid_t pid;
 	struct child_to_clean *next;
@@ -49,13 +53,14 @@ static void mark_child_for_cleanup(pid_t pid)
 
 static void clear_child_for_cleanup(pid_t pid)
 {
-	struct child_to_clean **last, *p;
+	struct child_to_clean **pp;
+
+	for (pp = &children_to_clean; *pp; pp = &(*pp)->next) {
+		struct child_to_clean *clean_me = *pp;
 
-	last = &children_to_clean;
-	for (p = children_to_clean; p; p = p->next) {
-		if (p->pid == pid) {
-			*last = p->next;
-			free(p);
+		if (clean_me->pid == pid) {
+			*pp = clean_me->next;
+			free(clean_me);
 			return;
 		}
 	}
@@ -67,15 +72,82 @@ static inline void close_pair(int fd[2])
 	close(fd[1]);
 }
 
-#ifndef WIN32
+#ifndef GIT_WINDOWS_NATIVE
 static inline void dup_devnull(int to)
 {
 	int fd = open("/dev/null", O_RDWR);
-	dup2(fd, to);
+	if (fd < 0)
+		die_errno(_("open /dev/null failed"));
+	if (dup2(fd, to) < 0)
+		die_errno(_("dup2(%d,%d) failed"), fd, to);
 	close(fd);
 }
 #endif
 
+static char *locate_in_PATH(const char *file)
+{
+	const char *p = getenv("PATH");
+	struct strbuf buf = STRBUF_INIT;
+
+	if (!p || !*p)
+		return NULL;
+
+	while (1) {
+		const char *end = strchrnul(p, ':');
+
+		strbuf_reset(&buf);
+
+		/* POSIX specifies an empty entry as the current directory. */
+		if (end != p) {
+			strbuf_add(&buf, p, end - p);
+			strbuf_addch(&buf, '/');
+		}
+		strbuf_addstr(&buf, file);
+
+		if (!access(buf.buf, F_OK))
+			return strbuf_detach(&buf, NULL);
+
+		if (!*end)
+			break;
+		p = end + 1;
+	}
+
+	strbuf_release(&buf);
+	return NULL;
+}
+
+static int exists_in_PATH(const char *file)
+{
+	char *r = locate_in_PATH(file);
+	free(r);
+	return r != NULL;
+}
+
+int sane_execvp(const char *file, char * const argv[])
+{
+	if (!execvp(file, argv))
+		return 0; /* cannot happen ;-) */
+
+	/*
+	 * When a command can't be found because one of the directories
+	 * listed in $PATH is unsearchable, execvp reports EACCES, but
+	 * careful usability testing (read: analysis of occasional bug
+	 * reports) reveals that "No such file or directory" is more
+	 * intuitive.
+	 *
+	 * We avoid commands with "/", because execvp will not do $PATH
+	 * lookups in that case.
+	 *
+	 * The reassignment of EACCES to errno looks like a no-op below,
+	 * but we need to protect against exists_in_PATH overwriting errno.
+	 */
+	if (errno == EACCES && !strchr(file, '/'))
+		errno = exists_in_PATH(file) ? EACCES : ENOENT;
+	else if (errno == ENOTDIR && !strchr(file, '/'))
+		errno = ENOENT;
+	return -1;
+}
+
 static const char **prepare_shell_cmd(const char **argv)
 {
 	int argc, nargc = 0;
@@ -90,7 +162,11 @@ static const char **prepare_shell_cmd(const char **argv)
 		die("BUG: shell command is empty");
 
 	if (strcspn(argv[0], "|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv[0])) {
+#ifndef GIT_WINDOWS_NATIVE
+		nargv[nargc++] = SHELL_PATH;
+#else
 		nargv[nargc++] = "sh";
+#endif
 		nargv[nargc++] = "-c";
 
 		if (argc < 2)
@@ -109,18 +185,18 @@ static const char **prepare_shell_cmd(const char **argv)
 	return nargv;
 }
 
-#ifndef WIN32
+#ifndef GIT_WINDOWS_NATIVE
 static int execv_shell_cmd(const char **argv)
 {
 	const char **nargv = prepare_shell_cmd(argv);
 	trace_argv_printf(nargv, "trace: exec:");
-	execvp(nargv[0], (char **)nargv);
+	sane_execvp(nargv[0], (char **)nargv);
 	free(nargv);
 	return -1;
 }
 #endif
 
-#ifndef WIN32
+#ifndef GIT_WINDOWS_NATIVE
 static int child_err = 2;
 static int child_notifier = -1;
 
@@ -153,7 +229,7 @@ static inline void set_cloexec(int fd)
 		fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
 }
 
-static int wait_or_whine(pid_t pid, const char *argv0, int silent_exec_failure)
+static int wait_or_whine(pid_t pid, const char *argv0)
 {
 	int status, code = -1;
 	pid_t waiting;
@@ -169,13 +245,14 @@ static int wait_or_whine(pid_t pid, const char *argv0, int silent_exec_failure)
 		error("waitpid is confused (%s)", argv0);
 	} else if (WIFSIGNALED(status)) {
 		code = WTERMSIG(status);
-		error("%s died of signal %d", argv0, code);
+		if (code != SIGINT && code != SIGQUIT)
+			error("%s died of signal %d", argv0, code);
 		/*
 		 * This return value is chosen so that code & 0xff
 		 * mimics the exit code that a POSIX shell would report for
 		 * a program that died from this signal.
 		 */
-		code -= 128;
+		code += 128;
 	} else if (WIFEXITED(status)) {
 		code = WEXITSTATUS(status);
 		/*
@@ -199,7 +276,8 @@ int start_command(struct child_process *cmd)
 {
 	int need_in, need_out, need_err;
 	int fdin[2], fdout[2], fderr[2];
-	int failed_errno = failed_errno;
+	int failed_errno;
+	char *str;
 
 	/*
 	 * In case of errors we must keep the promise to close FDs
@@ -212,6 +290,7 @@ int start_command(struct child_process *cmd)
 			failed_errno = errno;
 			if (cmd->out > 0)
 				close(cmd->out);
+			str = "standard input";
 			goto fail_pipe;
 		}
 		cmd->in = fdin[1];
@@ -227,6 +306,7 @@ int start_command(struct child_process *cmd)
 				close_pair(fdin);
 			else if (cmd->in)
 				close(cmd->in);
+			str = "standard output";
 			goto fail_pipe;
 		}
 		cmd->out = fdout[0];
@@ -244,9 +324,10 @@ int start_command(struct child_process *cmd)
 				close_pair(fdout);
 			else if (cmd->out)
 				close(cmd->out);
+			str = "standard error";
 fail_pipe:
-			error("cannot create pipe for %s: %s",
-				cmd->argv[0], strerror(failed_errno));
+			error("cannot create %s pipe for %s: %s",
+				str, cmd->argv[0], strerror(failed_errno));
 			errno = failed_errno;
 			return -1;
 		}
@@ -256,13 +337,14 @@ fail_pipe:
 	trace_argv_printf(cmd->argv, "trace: run_command:");
 	fflush(NULL);
 
-#ifndef WIN32
+#ifndef GIT_WINDOWS_NATIVE
 {
 	int notify_pipe[2];
 	if (pipe(notify_pipe))
 		notify_pipe[0] = notify_pipe[1] = -1;
 
 	cmd->pid = fork();
+	failed_errno = errno;
 	if (!cmd->pid) {
 		/*
 		 * Redirect the channel to write syscall error messages to
@@ -324,23 +406,12 @@ fail_pipe:
 					unsetenv(*cmd->env);
 			}
 		}
-		if (cmd->preexec_cb) {
-			/*
-			 * We cannot predict what the pre-exec callback does.
-			 * Forgo parent notification.
-			 */
-			close(child_notifier);
-			child_notifier = -1;
-
-			cmd->preexec_cb();
-		}
-		if (cmd->git_cmd) {
+		if (cmd->git_cmd)
 			execv_git_cmd(cmd->argv);
-		} else if (cmd->use_shell) {
+		else if (cmd->use_shell)
 			execv_shell_cmd(cmd->argv);
-		} else {
-			execvp(cmd->argv[0], (char *const*) cmd->argv);
-		}
+		else
+			sane_execvp(cmd->argv[0], (char *const*) cmd->argv);
 		if (errno == ENOENT) {
 			if (!cmd->silent_exec_failure)
 				error("cannot run %s: %s", cmd->argv[0],
@@ -352,7 +423,7 @@ fail_pipe:
 	}
 	if (cmd->pid < 0)
 		error("cannot fork() for %s: %s", cmd->argv[0],
-			strerror(failed_errno = errno));
+			strerror(errno));
 	else if (cmd->clean_on_exit)
 		mark_child_for_cleanup(cmd->pid);
 
@@ -369,13 +440,11 @@ fail_pipe:
 		 * At this point we know that fork() succeeded, but execvp()
 		 * failed. Errors have been reported to our stderr.
 		 */
-		wait_or_whine(cmd->pid, cmd->argv[0],
-			      cmd->silent_exec_failure);
+		wait_or_whine(cmd->pid, cmd->argv[0]);
 		failed_errno = errno;
 		cmd->pid = -1;
 	}
 	close(notify_pipe[0]);
-
 }
 #else
 {
@@ -409,11 +478,10 @@ fail_pipe:
 	if (cmd->env)
 		env = make_augmented_environ(cmd->env);
 
-	if (cmd->git_cmd) {
+	if (cmd->git_cmd)
 		cmd->argv = prepare_git_cmd(cmd->argv);
-	} else if (cmd->use_shell) {
+	else if (cmd->use_shell)
 		cmd->argv = prepare_shell_cmd(cmd->argv);
-	}
 
 	cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, env, cmd->dir,
 				  fhin, fhout, fherr);
@@ -475,7 +543,7 @@ fail_pipe:
 
 int finish_command(struct child_process *cmd)
 {
-	return wait_or_whine(cmd->pid, cmd->argv[0], cmd->silent_exec_failure);
+	return wait_or_whine(cmd->pid, cmd->argv[0]);
 }
 
 int run_command(struct child_process *cmd)
@@ -520,6 +588,7 @@ int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const
 static pthread_t main_thread;
 static int main_thread_set;
 static pthread_key_t async_key;
+static pthread_key_t async_die_counter;
 
 static void *run_thread(void *data)
 {
@@ -546,6 +615,14 @@ static NORETURN void die_async(const char *err, va_list params)
 
 	exit(128);
 }
+
+static int async_die_is_recursing(void)
+{
+	void *ret = pthread_getspecific(async_die_counter);
+	pthread_setspecific(async_die_counter, (void *)1);
+	return ret != NULL;
+}
+
 #endif
 
 int start_async(struct async *async)
@@ -627,7 +704,9 @@ int start_async(struct async *async)
 		main_thread_set = 1;
 		main_thread = pthread_self();
 		pthread_key_create(&async_key, NULL);
+		pthread_key_create(&async_die_counter, NULL);
 		set_die_routine(die_async);
+		set_die_is_recursing_routine(async_die_is_recursing);
 	}
 
 	if (proc_in >= 0)
@@ -662,7 +741,7 @@ error:
 int finish_async(struct async *async)
 {
 #ifdef NO_PTHREADS
-	return wait_or_whine(async->pid, "child process", 0);
+	return wait_or_whine(async->pid, "child process");
 #else
 	void *ret = (void *)(intptr_t)(-1);
 
@@ -672,6 +751,15 @@ int finish_async(struct async *async)
 #endif
 }
 
+char *find_hook(const char *name)
+{
+	char *path = git_path("hooks/%s", name);
+	if (access(path, X_OK) < 0)
+		path = NULL;
+
+	return path;
+}
+
 int run_hook(const char *index_file, const char *name, ...)
 {
 	struct child_process hook;
@@ -681,11 +769,13 @@ int run_hook(const char *index_file, const char *name, ...)
 	va_list args;
 	int ret;
 
-	if (access(git_path("hooks/%s", name), X_OK) < 0)
+	p = find_hook(name);
+	if (!p)
 		return 0;
 
+	argv_array_push(&argv, p);
+
 	va_start(args, name);
-	argv_array_push(&argv, git_path("hooks/%s", name));
 	while ((p = va_arg(args, const char *)))
 		argv_array_push(&argv, p);
 	va_end(args);