t/t4004-diff-rename-symlink.sh: use three-arg <prereq>
[gitweb.git] / run-command.c
index db30cd5fe29b9d9af11860da316ac1f45e290593..2a1041ef6599c84fff6a8d9faf5dea23a2af3ab0 100644 (file)
@@ -67,21 +67,24 @@ static int child_notifier = -1;
 
 static void notify_parent(void)
 {
-       write(child_notifier, "", 1);
+       ssize_t unused;
+       unused = write(child_notifier, "", 1);
 }
 
 static NORETURN void die_child(const char *err, va_list params)
 {
        char msg[4096];
+       ssize_t unused;
        int len = vsnprintf(msg, sizeof(msg), err, params);
        if (len > sizeof(msg))
                len = sizeof(msg);
 
-       write(child_err, "fatal: ", 7);
-       write(child_err, msg, len);
-       write(child_err, "\n", 1);
+       unused = write(child_err, "fatal: ", 7);
+       unused = write(child_err, msg, len);
+       unused = write(child_err, "\n", 1);
        exit(128);
 }
+#endif
 
 static inline void set_cloexec(int fd)
 {
@@ -89,7 +92,6 @@ static inline void set_cloexec(int fd)
        if (flags >= 0)
                fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
 }
-#endif
 
 static int wait_or_whine(pid_t pid, const char *argv0, int silent_exec_failure)
 {
@@ -233,6 +235,9 @@ int start_command(struct child_process *cmd)
                else if (need_err) {
                        dup2(fderr[1], 2);
                        close_pair(fderr);
+               } else if (cmd->err > 1) {
+                       dup2(cmd->err, 2);
+                       close(cmd->err);
                }
 
                if (cmd->no_stdout)
@@ -325,6 +330,8 @@ int start_command(struct child_process *cmd)
                fherr = open("/dev/null", O_RDWR);
        else if (need_err)
                fherr = dup(fderr[1]);
+       else if (cmd->err > 2)
+               fherr = dup(cmd->err);
 
        if (cmd->no_stdout)
                fhout = open("/dev/null", O_RDWR);
@@ -376,6 +383,8 @@ int start_command(struct child_process *cmd)
                        close(cmd->out);
                if (need_err)
                        close_pair(fderr);
+               else if (cmd->err)
+                       close(cmd->err);
                errno = failed_errno;
                return -1;
        }
@@ -392,6 +401,8 @@ int start_command(struct child_process *cmd)
 
        if (need_err)
                close(fderr[1]);
+       else if (cmd->err)
+               close(cmd->err);
 
        return 0;
 }
@@ -438,62 +449,158 @@ int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const
        return run_command(&cmd);
 }
 
-#ifdef WIN32
-static unsigned __stdcall run_thread(void *data)
+#ifndef NO_PTHREADS
+static pthread_t main_thread;
+static int main_thread_set;
+static pthread_key_t async_key;
+
+static void *run_thread(void *data)
 {
        struct async *async = data;
-       return async->proc(async->fd_for_proc, async->data);
+       intptr_t ret;
+
+       pthread_setspecific(async_key, async);
+       ret = async->proc(async->proc_in, async->proc_out, async->data);
+       return (void *)ret;
+}
+
+static NORETURN void die_async(const char *err, va_list params)
+{
+       vreportf("fatal: ", err, params);
+
+       if (!pthread_equal(main_thread, pthread_self())) {
+               struct async *async = pthread_getspecific(async_key);
+               if (async->proc_in >= 0)
+                       close(async->proc_in);
+               if (async->proc_out >= 0)
+                       close(async->proc_out);
+               pthread_exit((void *)128);
+       }
+
+       exit(128);
 }
 #endif
 
 int start_async(struct async *async)
 {
-       int pipe_out[2];
+       int need_in, need_out;
+       int fdin[2], fdout[2];
+       int proc_in, proc_out;
 
-       if (pipe(pipe_out) < 0)
-               return error("cannot create pipe: %s", strerror(errno));
-       async->out = pipe_out[0];
+       need_in = async->in < 0;
+       if (need_in) {
+               if (pipe(fdin) < 0) {
+                       if (async->out > 0)
+                               close(async->out);
+                       return error("cannot create pipe: %s", strerror(errno));
+               }
+               async->in = fdin[1];
+       }
 
-#ifndef WIN32
+       need_out = async->out < 0;
+       if (need_out) {
+               if (pipe(fdout) < 0) {
+                       if (need_in)
+                               close_pair(fdin);
+                       else if (async->in)
+                               close(async->in);
+                       return error("cannot create pipe: %s", strerror(errno));
+               }
+               async->out = fdout[0];
+       }
+
+       if (need_in)
+               proc_in = fdin[0];
+       else if (async->in)
+               proc_in = async->in;
+       else
+               proc_in = -1;
+
+       if (need_out)
+               proc_out = fdout[1];
+       else if (async->out)
+               proc_out = async->out;
+       else
+               proc_out = -1;
+
+#ifdef NO_PTHREADS
        /* Flush stdio before fork() to avoid cloning buffers */
        fflush(NULL);
 
        async->pid = fork();
        if (async->pid < 0) {
                error("fork (async) failed: %s", strerror(errno));
-               close_pair(pipe_out);
-               return -1;
+               goto error;
        }
        if (!async->pid) {
-               close(pipe_out[0]);
-               exit(!!async->proc(pipe_out[1], async->data));
+               if (need_in)
+                       close(fdin[1]);
+               if (need_out)
+                       close(fdout[0]);
+               exit(!!async->proc(proc_in, proc_out, async->data));
        }
-       close(pipe_out[1]);
+
+       if (need_in)
+               close(fdin[0]);
+       else if (async->in)
+               close(async->in);
+
+       if (need_out)
+               close(fdout[1]);
+       else if (async->out)
+               close(async->out);
 #else
-       async->fd_for_proc = pipe_out[1];
-       async->tid = (HANDLE) _beginthreadex(NULL, 0, run_thread, async, 0, NULL);
-       if (!async->tid) {
-               error("cannot create thread: %s", strerror(errno));
-               close_pair(pipe_out);
-               return -1;
+       if (!main_thread_set) {
+               /*
+                * We assume that the first time that start_async is called
+                * it is from the main thread.
+                */
+               main_thread_set = 1;
+               main_thread = pthread_self();
+               pthread_key_create(&async_key, NULL);
+               set_die_routine(die_async);
+       }
+
+       if (proc_in >= 0)
+               set_cloexec(proc_in);
+       if (proc_out >= 0)
+               set_cloexec(proc_out);
+       async->proc_in = proc_in;
+       async->proc_out = proc_out;
+       {
+               int err = pthread_create(&async->tid, NULL, run_thread, async);
+               if (err) {
+                       error("cannot create thread: %s", strerror(err));
+                       goto error;
+               }
        }
 #endif
        return 0;
+
+error:
+       if (need_in)
+               close_pair(fdin);
+       else if (async->in)
+               close(async->in);
+
+       if (need_out)
+               close_pair(fdout);
+       else if (async->out)
+               close(async->out);
+       return -1;
 }
 
 int finish_async(struct async *async)
 {
-#ifndef WIN32
-       int ret = wait_or_whine(async->pid, "child process", 0);
+#ifdef NO_PTHREADS
+       return wait_or_whine(async->pid, "child process", 0);
 #else
-       DWORD ret = 0;
-       if (WaitForSingleObject(async->tid, INFINITE) != WAIT_OBJECT_0)
-               ret = error("waiting for thread failed: %lu", GetLastError());
-       else if (!GetExitCodeThread(async->tid, &ret))
-               ret = error("cannot get thread exit code: %lu", GetLastError());
-       CloseHandle(async->tid);
+       void *ret = (void *)(intptr_t)(-1);
+
+       if (pthread_join(async->tid, &ret))
+               error("pthread_join failed");
+       return (int)(intptr_t)ret;
 #endif
-       return ret;
 }
 
 int run_hook(const char *index_file, const char *name, ...)