close(fd[1]);
}
+#ifndef WIN32
static inline void dup_devnull(int to)
{
int fd = open("/dev/null", O_RDWR);
dup2(fd, to);
close(fd);
}
+#endif
+
+static const char **prepare_shell_cmd(const char **argv)
+{
+ int argc, nargc = 0;
+ const char **nargv;
+
+ for (argc = 0; argv[argc]; argc++)
+ ; /* just counting */
+ /* +1 for NULL, +3 for "sh -c" plus extra $0 */
+ nargv = xmalloc(sizeof(*nargv) * (argc + 1 + 3));
+
+ if (argc < 1)
+ die("BUG: shell command is empty");
+
+ if (strcspn(argv[0], "|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv[0])) {
+ nargv[nargc++] = "sh";
+ nargv[nargc++] = "-c";
+
+ if (argc < 2)
+ nargv[nargc++] = argv[0];
+ else {
+ struct strbuf arg0 = STRBUF_INIT;
+ strbuf_addf(&arg0, "%s \"$@\"", argv[0]);
+ nargv[nargc++] = strbuf_detach(&arg0, NULL);
+ }
+ }
+
+ for (argc = 0; argv[argc]; argc++)
+ nargv[nargc++] = argv[argc];
+ nargv[nargc] = NULL;
+
+ return nargv;
+}
+
+#ifndef WIN32
+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);
+ free(nargv);
+ return -1;
+}
+#endif
#ifndef WIN32
static int child_err = 2;
+static int child_notifier = -1;
+
+static void notify_parent(void)
+{
+ write(child_notifier, "", 1);
+}
static NORETURN void die_child(const char *err, va_list params)
{
}
#endif
+static int wait_or_whine(pid_t pid, const char *argv0, int silent_exec_failure)
+{
+ int status, code = -1;
+ pid_t waiting;
+ int failed_errno = 0;
+
+ while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR)
+ ; /* nothing */
+
+ if (waiting < 0) {
+ failed_errno = errno;
+ error("waitpid for %s failed: %s", argv0, strerror(errno));
+ } else if (waiting != pid) {
+ error("waitpid is confused (%s)", argv0);
+ } else if (WIFSIGNALED(status)) {
+ code = WTERMSIG(status);
+ 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;
+ } else if (WIFEXITED(status)) {
+ code = WEXITSTATUS(status);
+ /*
+ * Convert special exit code when execvp failed.
+ */
+ if (code == 127) {
+ code = -1;
+ failed_errno = ENOENT;
+ if (!silent_exec_failure)
+ error("cannot run %s: %s", argv0,
+ strerror(ENOENT));
+ }
+ } else {
+ error("waitpid is confused (%s)", argv0);
+ }
+ errno = failed_errno;
+ return code;
+}
+
int start_command(struct child_process *cmd)
{
int need_in, need_out, need_err;
trace_argv_printf(cmd->argv, "trace: run_command:");
#ifndef WIN32
+{
+ int notify_pipe[2];
+ if (pipe(notify_pipe))
+ notify_pipe[0] = notify_pipe[1] = -1;
+
fflush(NULL);
cmd->pid = fork();
if (!cmd->pid) {
}
set_die_routine(die_child);
+ close(notify_pipe[0]);
+ set_cloexec(notify_pipe[1]);
+ child_notifier = notify_pipe[1];
+ atexit(notify_parent);
+
if (cmd->no_stdin)
dup_devnull(0);
else if (need_in) {
unsetenv(*cmd->env);
}
}
- if (cmd->preexec_cb)
+ 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) {
execv_git_cmd(cmd->argv);
+ } else if (cmd->use_shell) {
+ execv_shell_cmd(cmd->argv);
} else {
execvp(cmd->argv[0], (char *const*) cmd->argv);
}
if (cmd->pid < 0)
error("cannot fork() for %s: %s", cmd->argv[0],
strerror(failed_errno = errno));
+
+ /*
+ * Wait for child's execvp. If the execvp succeeds (or if fork()
+ * failed), EOF is seen immediately by the parent. Otherwise, the
+ * child process sends a single byte.
+ * Note that use of this infrastructure is completely advisory,
+ * therefore, we keep error checks minimal.
+ */
+ close(notify_pipe[1]);
+ if (read(notify_pipe[0], ¬ify_pipe[1], 1) == 1) {
+ /*
+ * 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);
+ failed_errno = errno;
+ cmd->pid = -1;
+ }
+ close(notify_pipe[0]);
+}
#else
{
- int s0 = -1, s1 = -1, s2 = -1; /* backups of stdin, stdout, stderr */
+ int fhin = 0, fhout = 1, fherr = 2;
const char **sargv = cmd->argv;
char **env = environ;
- if (cmd->no_stdin) {
- s0 = dup(0);
- dup_devnull(0);
- } else if (need_in) {
- s0 = dup(0);
- dup2(fdin[0], 0);
- } else if (cmd->in) {
- s0 = dup(0);
- dup2(cmd->in, 0);
- }
-
- if (cmd->no_stderr) {
- s2 = dup(2);
- dup_devnull(2);
- } else if (need_err) {
- s2 = dup(2);
- dup2(fderr[1], 2);
- }
-
- if (cmd->no_stdout) {
- s1 = dup(1);
- dup_devnull(1);
- } else if (cmd->stdout_to_stderr) {
- s1 = dup(1);
- dup2(2, 1);
- } else if (need_out) {
- s1 = dup(1);
- dup2(fdout[1], 1);
- } else if (cmd->out > 1) {
- s1 = dup(1);
- dup2(cmd->out, 1);
- }
+ if (cmd->no_stdin)
+ fhin = open("/dev/null", O_RDWR);
+ else if (need_in)
+ fhin = dup(fdin[0]);
+ else if (cmd->in)
+ fhin = dup(cmd->in);
+
+ if (cmd->no_stderr)
+ fherr = open("/dev/null", O_RDWR);
+ else if (need_err)
+ fherr = dup(fderr[1]);
+
+ if (cmd->no_stdout)
+ fhout = open("/dev/null", O_RDWR);
+ else if (cmd->stdout_to_stderr)
+ fhout = dup(fherr);
+ else if (need_out)
+ fhout = dup(fdout[1]);
+ else if (cmd->out > 1)
+ fhout = dup(cmd->out);
if (cmd->dir)
die("chdir in start_command() not implemented");
if (cmd->git_cmd) {
cmd->argv = prepare_git_cmd(cmd->argv);
+ } else if (cmd->use_shell) {
+ cmd->argv = prepare_shell_cmd(cmd->argv);
}
- cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, env);
+ cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, env,
+ fhin, fhout, fherr);
failed_errno = errno;
if (cmd->pid < 0 && (!cmd->silent_exec_failure || errno != ENOENT))
error("cannot spawn %s: %s", cmd->argv[0], strerror(errno));
free(cmd->argv);
cmd->argv = sargv;
- if (s0 >= 0)
- dup2(s0, 0), close(s0);
- if (s1 >= 0)
- dup2(s1, 1), close(s1);
- if (s2 >= 0)
- dup2(s2, 2), close(s2);
+ if (fhin != 0)
+ close(fhin);
+ if (fhout != 1)
+ close(fhout);
+ if (fherr != 2)
+ close(fherr);
}
#endif
return 0;
}
-static int wait_or_whine(pid_t pid, const char *argv0, int silent_exec_failure)
-{
- int status, code = -1;
- pid_t waiting;
- int failed_errno = 0;
-
- while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR)
- ; /* nothing */
-
- if (waiting < 0) {
- failed_errno = errno;
- error("waitpid for %s failed: %s", argv0, strerror(errno));
- } else if (waiting != pid) {
- error("waitpid is confused (%s)", argv0);
- } else if (WIFSIGNALED(status)) {
- code = WTERMSIG(status);
- 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;
- } else if (WIFEXITED(status)) {
- code = WEXITSTATUS(status);
- /*
- * Convert special exit code when execvp failed.
- */
- if (code == 127) {
- code = -1;
- failed_errno = ENOENT;
- if (!silent_exec_failure)
- error("cannot run %s: %s", argv0,
- strerror(ENOENT));
- }
- } else {
- error("waitpid is confused (%s)", argv0);
- }
- errno = failed_errno;
- return code;
-}
-
int finish_command(struct child_process *cmd)
{
return wait_or_whine(cmd->pid, cmd->argv[0], cmd->silent_exec_failure);
cmd->git_cmd = opt & RUN_GIT_CMD ? 1 : 0;
cmd->stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0;
cmd->silent_exec_failure = opt & RUN_SILENT_EXEC_FAILURE ? 1 : 0;
+ cmd->use_shell = opt & RUN_USING_SHELL ? 1 : 0;
}
int run_command_v_opt(const char **argv, int opt)