#include "cache.h"
#include "run-command.h"
#include "exec_cmd.h"
+#include "sigchain.h"
+#include "argv-array.h"
+#include "thread-utils.h"
+#include "strbuf.h"
+
+void child_process_init(struct child_process *child)
+{
+ memset(child, 0, sizeof(*child));
+ argv_array_init(&child->args);
+ argv_array_init(&child->env_array);
+}
+
+void child_process_clear(struct child_process *child)
+{
+ argv_array_clear(&child->args);
+ argv_array_clear(&child->env_array);
+}
+
+struct child_to_clean {
+ pid_t pid;
+ struct child_to_clean *next;
+};
+static struct child_to_clean *children_to_clean;
+static int installed_child_cleanup_handler;
+
+static void cleanup_children(int sig, int in_signal)
+{
+ while (children_to_clean) {
+ struct child_to_clean *p = children_to_clean;
+ children_to_clean = p->next;
+ kill(p->pid, sig);
+ if (!in_signal)
+ free(p);
+ }
+}
+
+static void cleanup_children_on_signal(int sig)
+{
+ cleanup_children(sig, 1);
+ sigchain_pop(sig);
+ raise(sig);
+}
+
+static void cleanup_children_on_exit(void)
+{
+ cleanup_children(SIGTERM, 0);
+}
+
+static void mark_child_for_cleanup(pid_t pid)
+{
+ struct child_to_clean *p = xmalloc(sizeof(*p));
+ p->pid = pid;
+ p->next = children_to_clean;
+ children_to_clean = p;
+
+ if (!installed_child_cleanup_handler) {
+ atexit(cleanup_children_on_exit);
+ sigchain_push_common(cleanup_children_on_signal);
+ installed_child_cleanup_handler = 1;
+ }
+}
+
+static void clear_child_for_cleanup(pid_t pid)
+{
+ struct child_to_clean **pp;
+
+ for (pp = &children_to_clean; *pp; pp = &(*pp)->next) {
+ struct child_to_clean *clean_me = *pp;
+
+ if (clean_me->pid == pid) {
+ *pp = clean_me->next;
+ free(clean_me);
+ return;
+ }
+ }
+}
static inline void close_pair(int fd[2])
{
close(fd[1]);
}
+#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 $PATH
+ * lookups in that case.
+ *
+ * The reassignment of EACCES to errno looks like a no-op below,
+ * but we need to protect against exists_in_PATH overwriting errno.
+ */
+ if (errno == EACCES && !strchr(file, '/'))
+ errno = exists_in_PATH(file) ? EACCES : ENOENT;
+ else if (errno == ENOTDIR && !strchr(file, '/'))
+ errno = ENOENT;
+ return -1;
+}
+
+static const char **prepare_shell_cmd(struct argv_array *out, const char **argv)
+{
+ if (!argv[0])
+ die("BUG: shell command is empty");
+
+ if (strcspn(argv[0], "|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv[0])) {
+#ifndef GIT_WINDOWS_NATIVE
+ argv_array_push(out, SHELL_PATH);
+#else
+ argv_array_push(out, "sh");
+#endif
+ argv_array_push(out, "-c");
+
+ /*
+ * If we have no extra arguments, we do not even need to
+ * bother with the "$@" magic.
+ */
+ if (!argv[1])
+ argv_array_push(out, argv[0]);
+ else
+ argv_array_pushf(out, "%s \"$@\"", argv[0]);
+ }
+
+ argv_array_pushv(out, argv);
+ return out->argv;
+}
+
+#ifndef GIT_WINDOWS_NATIVE
+static int execv_shell_cmd(const char **argv)
+{
+ struct argv_array nargv = ARGV_ARRAY_INIT;
+ prepare_shell_cmd(&nargv, argv);
+ trace_argv_printf(nargv.argv, "trace: exec:");
+ sane_execvp(nargv.argv[0], (char **)nargv.argv);
+ argv_array_clear(&nargv);
+ return -1;
+}
+#endif
+
+#ifndef GIT_WINDOWS_NATIVE
+static int child_notifier = -1;
+
+static void notify_parent(void)
+{
+ /*
+ * execvp failed. If possible, we'd like to let start_command
+ * know, so failures like ENOENT can be handled right away; but
+ * otherwise, finish_command will still report the error.
+ */
+ xwrite(child_notifier, "", 1);
+}
+#endif
+
+static inline void set_cloexec(int fd)
+{
+ int flags = fcntl(fd, F_GETFD);
+ if (flags >= 0)
+ fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
+}
+
+static int wait_or_whine(pid_t pid, const char *argv0, int in_signal)
+{
+ int status, code = -1;
+ pid_t waiting;
+ int failed_errno = 0;
+
+ while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR)
+ ; /* nothing */
+ if (in_signal)
+ return 0;
+
+ if (waiting < 0) {
+ failed_errno = errno;
+ error_errno("waitpid for %s failed", argv0);
+ } else if (waiting != pid) {
+ error("waitpid is confused (%s)", argv0);
+ } else if (WIFSIGNALED(status)) {
+ code = WTERMSIG(status);
+ if (code != SIGINT && code != SIGQUIT && code != SIGPIPE)
+ 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;
+ }
+ } else {
+ error("waitpid is confused (%s)", argv0);
+ }
+
+ clear_child_for_cleanup(pid);
+
+ errno = failed_errno;
+ return code;
+}
int start_command(struct child_process *cmd)
{
int need_in, need_out, need_err;
int fdin[2], fdout[2], fderr[2];
+ int failed_errno;
+ char *str;
+
+ if (!cmd->argv)
+ cmd->argv = cmd->args.argv;
+ if (!cmd->env)
+ cmd->env = cmd->env_array.argv;
/*
* In case of errors we must keep the promise to close FDs
need_in = !cmd->no_stdin && cmd->in < 0;
if (need_in) {
if (pipe(fdin) < 0) {
+ failed_errno = errno;
if (cmd->out > 0)
close(cmd->out);
- return -ERR_RUN_COMMAND_PIPE;
+ str = "standard input";
+ goto fail_pipe;
}
cmd->in = fdin[1];
}
&& cmd->out < 0;
if (need_out) {
if (pipe(fdout) < 0) {
+ failed_errno = errno;
if (need_in)
close_pair(fdin);
else if (cmd->in)
close(cmd->in);
- return -ERR_RUN_COMMAND_PIPE;
+ str = "standard output";
+ goto fail_pipe;
}
cmd->out = fdout[0];
}
need_err = !cmd->no_stderr && cmd->err < 0;
if (need_err) {
if (pipe(fderr) < 0) {
+ failed_errno = errno;
if (need_in)
close_pair(fdin);
else if (cmd->in)
close_pair(fdout);
else if (cmd->out)
close(cmd->out);
- return -ERR_RUN_COMMAND_PIPE;
+ str = "standard error";
+fail_pipe:
+ error("cannot create %s pipe for %s: %s",
+ str, cmd->argv[0], strerror(failed_errno));
+ child_process_clear(cmd);
+ errno = failed_errno;
+ return -1;
}
cmd->err = fderr[0];
}
trace_argv_printf(cmd->argv, "trace: run_command:");
-
-#ifndef __MINGW32__
fflush(NULL);
+
+#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
+ * before redirecting the process's stderr so that all die()
+ * in subsequent call paths use the parent's stderr.
+ */
+ if (cmd->no_stderr || need_err) {
+ int child_err = dup(2);
+ set_cloexec(child_err);
+ set_error_handle(fdopen(child_err, "w"));
+ }
+
+ 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) {
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)
}
if (cmd->dir && chdir(cmd->dir))
- die("exec %s: cd to %s failed (%s)", cmd->argv[0],
- cmd->dir, strerror(errno));
+ die_errno("exec '%s': cd to '%s' failed", cmd->argv[0],
+ cmd->dir);
if (cmd->env) {
for (; *cmd->env; cmd->env++) {
if (strchr(*cmd->env, '='))
- putenv((char*)*cmd->env);
+ putenv((char *)*cmd->env);
else
unsetenv(*cmd->env);
}
}
- if (cmd->git_cmd) {
+ if (cmd->git_cmd)
execv_git_cmd(cmd->argv);
+ else if (cmd->use_shell)
+ execv_shell_cmd(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],
+ strerror(ENOENT));
+ exit(127);
} else {
- execvp(cmd->argv[0], (char *const*) cmd->argv);
+ die_errno("cannot exec '%s'", cmd->argv[0]);
}
- die("exec %s failed.", cmd->argv[0]);
- }
-#else
- int s0 = -1, s1 = -1, s2 = -1; /* backups of stdin, stdout, stderr */
- 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->pid < 0)
+ error_errno("cannot fork() for %s", cmd->argv[0]);
+ else if (cmd->clean_on_exit)
+ mark_child_for_cleanup(cmd->pid);
- 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);
+ /*
+ * 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], 0);
+ failed_errno = errno;
+ cmd->pid = -1;
}
+ close(notify_pipe[0]);
+}
+#else
+{
+ int fhin = 0, fhout = 1, fherr = 2;
+ const char **sargv = cmd->argv;
+ struct argv_array nargv = ARGV_ARRAY_INIT;
- if (cmd->dir)
- die("chdir in start_command() not implemented");
- if (cmd->env) {
- env = copy_environ();
- for (; *cmd->env; cmd->env++)
- env = env_setenv(env, *cmd->env);
- }
+ 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->git_cmd) {
- cmd->argv = prepare_git_cmd(cmd->argv);
- }
+ if (cmd->no_stderr)
+ fherr = open("/dev/null", O_RDWR);
+ else if (need_err)
+ fherr = dup(fderr[1]);
+ else if (cmd->err > 2)
+ fherr = dup(cmd->err);
- cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, env);
+ 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->env)
- free_environ(env);
if (cmd->git_cmd)
- free(cmd->argv);
+ cmd->argv = prepare_git_cmd(&nargv, cmd->argv);
+ else if (cmd->use_shell)
+ cmd->argv = prepare_shell_cmd(&nargv, cmd->argv);
+ cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, (char**) cmd->env,
+ cmd->dir, fhin, fhout, fherr);
+ failed_errno = errno;
+ if (cmd->pid < 0 && (!cmd->silent_exec_failure || errno != ENOENT))
+ error_errno("cannot spawn %s", cmd->argv[0]);
+ if (cmd->clean_on_exit && cmd->pid >= 0)
+ mark_child_for_cleanup(cmd->pid);
+
+ argv_array_clear(&nargv);
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
if (cmd->pid < 0) {
close(cmd->out);
if (need_err)
close_pair(fderr);
- return -ERR_RUN_COMMAND_FORK;
+ else if (cmd->err)
+ close(cmd->err);
+ child_process_clear(cmd);
+ errno = failed_errno;
+ return -1;
}
if (need_in)
if (need_err)
close(fderr[1]);
+ else if (cmd->err)
+ close(cmd->err);
return 0;
}
-static int wait_or_whine(pid_t pid)
+int finish_command(struct child_process *cmd)
{
- for (;;) {
- int status, code;
- pid_t waiting = waitpid(pid, &status, 0);
-
- if (waiting < 0) {
- if (errno == EINTR)
- continue;
- error("waitpid failed (%s)", strerror(errno));
- return -ERR_RUN_COMMAND_WAITPID;
- }
- if (waiting != pid)
- return -ERR_RUN_COMMAND_WAITPID_WRONG_PID;
- if (WIFSIGNALED(status))
- return -ERR_RUN_COMMAND_WAITPID_SIGNAL;
-
- if (!WIFEXITED(status))
- return -ERR_RUN_COMMAND_WAITPID_NOEXIT;
- code = WEXITSTATUS(status);
- if (code)
- return -code;
- return 0;
- }
+ int ret = wait_or_whine(cmd->pid, cmd->argv[0], 0);
+ child_process_clear(cmd);
+ return ret;
}
-int finish_command(struct child_process *cmd)
+int finish_command_in_signal(struct child_process *cmd)
{
- return wait_or_whine(cmd->pid);
+ return wait_or_whine(cmd->pid, cmd->argv[0], 1);
}
+
int run_command(struct child_process *cmd)
{
- int code = start_command(cmd);
+ int code;
+
+ if (cmd->out < 0 || cmd->err < 0)
+ die("BUG: run_command with a pipe can cause deadlock");
+
+ code = start_command(cmd);
if (code)
return code;
return finish_command(cmd);
}
-static void prepare_run_command_v_opt(struct child_process *cmd,
- const char **argv,
- int opt)
+int run_command_v_opt(const char **argv, int opt)
{
- memset(cmd, 0, sizeof(*cmd));
- cmd->argv = argv;
- cmd->no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0;
- cmd->git_cmd = opt & RUN_GIT_CMD ? 1 : 0;
- cmd->stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0;
+ return run_command_v_opt_cd_env(argv, opt, NULL, NULL);
}
-int run_command_v_opt(const char **argv, int opt)
+int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env)
{
- struct child_process cmd;
- prepare_run_command_v_opt(&cmd, argv, opt);
+ struct child_process cmd = CHILD_PROCESS_INIT;
+ cmd.argv = argv;
+ cmd.no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0;
+ 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;
+ cmd.clean_on_exit = opt & RUN_CLEAN_ON_EXIT ? 1 : 0;
+ cmd.dir = dir;
+ cmd.env = env;
return run_command(&cmd);
}
-int run_command_v_opt_cd(const char **argv, int opt, const char *dir)
+#ifndef NO_PTHREADS
+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)
{
- struct child_process cmd;
- prepare_run_command_v_opt(&cmd, argv, opt);
- cmd.dir = dir;
- return run_command(&cmd);
+ struct async *async = data;
+ intptr_t ret;
+
+ if (async->isolate_sigpipe) {
+ sigset_t mask;
+ sigemptyset(&mask);
+ sigaddset(&mask, SIGPIPE);
+ if (pthread_sigmask(SIG_BLOCK, &mask, NULL) < 0) {
+ ret = error("unable to block SIGPIPE in async thread");
+ return (void *)ret;
+ }
+ }
+
+ pthread_setspecific(async_key, async);
+ ret = async->proc(async->proc_in, async->proc_out, async->data);
+ return (void *)ret;
}
-int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env)
+static NORETURN void die_async(const char *err, va_list params)
{
- struct child_process cmd;
- prepare_run_command_v_opt(&cmd, argv, opt);
- cmd.dir = dir;
- cmd.env = env;
- return run_command(&cmd);
+ vreportf("fatal: ", err, params);
+
+ if (in_async()) {
+ 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);
}
-#ifdef __MINGW32__
-static __stdcall unsigned run_thread(void *data)
+static int async_die_is_recursing(void)
{
- struct async *async = data;
- return async->proc(async->fd_for_proc, async->data);
+ void *ret = pthread_getspecific(async_die_counter);
+ pthread_setspecific(async_die_counter, (void *)1);
+ return ret != NULL;
+}
+
+int in_async(void)
+{
+ if (!main_thread_set)
+ return 0; /* no asyncs started yet */
+ return !pthread_equal(main_thread, pthread_self());
+}
+
+void NORETURN async_exit(int code)
+{
+ pthread_exit((void *)(intptr_t)code);
+}
+
+#else
+
+static struct {
+ void (**handlers)(void);
+ size_t nr;
+ size_t alloc;
+} git_atexit_hdlrs;
+
+static int git_atexit_installed;
+
+static void git_atexit_dispatch(void)
+{
+ size_t i;
+
+ for (i=git_atexit_hdlrs.nr ; i ; i--)
+ git_atexit_hdlrs.handlers[i-1]();
+}
+
+static void git_atexit_clear(void)
+{
+ free(git_atexit_hdlrs.handlers);
+ memset(&git_atexit_hdlrs, 0, sizeof(git_atexit_hdlrs));
+ git_atexit_installed = 0;
}
+
+#undef atexit
+int git_atexit(void (*handler)(void))
+{
+ ALLOC_GROW(git_atexit_hdlrs.handlers, git_atexit_hdlrs.nr + 1, git_atexit_hdlrs.alloc);
+ git_atexit_hdlrs.handlers[git_atexit_hdlrs.nr++] = handler;
+ if (!git_atexit_installed) {
+ if (atexit(&git_atexit_dispatch))
+ return -1;
+ git_atexit_installed = 1;
+ }
+ return 0;
+}
+#define atexit git_atexit
+
+static int process_is_async;
+int in_async(void)
+{
+ return process_is_async;
+}
+
+void NORETURN async_exit(int code)
+{
+ exit(code);
+}
+
#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_errno("cannot create pipe");
+ }
+ async->in = fdin[1];
+ }
+
+ 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_errno("cannot create pipe");
+ }
+ async->out = fdout[0];
+ }
-#ifndef __MINGW32__
+ 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;
+ error_errno("fork (async) failed");
+ 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]);
+ git_atexit_clear();
+ process_is_async = 1;
+ exit(!!async->proc(proc_in, proc_out, async->data));
}
- close(pipe_out[1]);
+
+ mark_child_for_cleanup(async->pid);
+
+ 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);
+ 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)
+ 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_errno("cannot create thread");
+ 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 __MINGW32__
- int ret = 0;
-
- if (wait_or_whine(async->pid))
- ret = error("waitpid (async) failed");
+#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
+}
+
+const char *find_hook(const char *name)
+{
+ static struct strbuf path = STRBUF_INIT;
+
+ strbuf_reset(&path);
+ if (git_hooks_path)
+ strbuf_addf(&path, "%s/%s", git_hooks_path, name);
+ else
+ strbuf_git_path(&path, "hooks/%s", name);
+ if (access(path.buf, X_OK) < 0)
+ return NULL;
+ return path.buf;
+}
+
+int run_hook_ve(const char *const *env, const char *name, va_list args)
+{
+ struct child_process hook = CHILD_PROCESS_INIT;
+ const char *p;
+
+ p = find_hook(name);
+ if (!p)
+ return 0;
+
+ argv_array_push(&hook.args, p);
+ while ((p = va_arg(args, const char *)))
+ argv_array_push(&hook.args, p);
+ hook.env = env;
+ hook.no_stdin = 1;
+ hook.stdout_to_stderr = 1;
+
+ return run_command(&hook);
+}
+
+int run_hook_le(const char *const *env, const char *name, ...)
+{
+ va_list args;
+ int ret;
+
+ va_start(args, name);
+ ret = run_hook_ve(env, name, args);
+ va_end(args);
+
return ret;
}
+
+struct io_pump {
+ /* initialized by caller */
+ int fd;
+ int type; /* POLLOUT or POLLIN */
+ union {
+ struct {
+ const char *buf;
+ size_t len;
+ } out;
+ struct {
+ struct strbuf *buf;
+ size_t hint;
+ } in;
+ } u;
+
+ /* returned by pump_io */
+ int error; /* 0 for success, otherwise errno */
+
+ /* internal use */
+ struct pollfd *pfd;
+};
+
+static int pump_io_round(struct io_pump *slots, int nr, struct pollfd *pfd)
+{
+ int pollsize = 0;
+ int i;
+
+ for (i = 0; i < nr; i++) {
+ struct io_pump *io = &slots[i];
+ if (io->fd < 0)
+ continue;
+ pfd[pollsize].fd = io->fd;
+ pfd[pollsize].events = io->type;
+ io->pfd = &pfd[pollsize++];
+ }
+
+ if (!pollsize)
+ return 0;
+
+ if (poll(pfd, pollsize, -1) < 0) {
+ if (errno == EINTR)
+ return 1;
+ die_errno("poll failed");
+ }
+
+ for (i = 0; i < nr; i++) {
+ struct io_pump *io = &slots[i];
+
+ if (io->fd < 0)
+ continue;
+
+ if (!(io->pfd->revents & (POLLOUT|POLLIN|POLLHUP|POLLERR|POLLNVAL)))
+ continue;
+
+ if (io->type == POLLOUT) {
+ ssize_t len = xwrite(io->fd,
+ io->u.out.buf, io->u.out.len);
+ if (len < 0) {
+ io->error = errno;
+ close(io->fd);
+ io->fd = -1;
+ } else {
+ io->u.out.buf += len;
+ io->u.out.len -= len;
+ if (!io->u.out.len) {
+ close(io->fd);
+ io->fd = -1;
+ }
+ }
+ }
+
+ if (io->type == POLLIN) {
+ ssize_t len = strbuf_read_once(io->u.in.buf,
+ io->fd, io->u.in.hint);
+ if (len < 0)
+ io->error = errno;
+ if (len <= 0) {
+ close(io->fd);
+ io->fd = -1;
+ }
+ }
+ }
+
+ return 1;
+}
+
+static int pump_io(struct io_pump *slots, int nr)
+{
+ struct pollfd *pfd;
+ int i;
+
+ for (i = 0; i < nr; i++)
+ slots[i].error = 0;
+
+ ALLOC_ARRAY(pfd, nr);
+ while (pump_io_round(slots, nr, pfd))
+ ; /* nothing */
+ free(pfd);
+
+ /* There may be multiple errno values, so just pick the first. */
+ for (i = 0; i < nr; i++) {
+ if (slots[i].error) {
+ errno = slots[i].error;
+ return -1;
+ }
+ }
+ return 0;
+}
+
+
+int pipe_command(struct child_process *cmd,
+ const char *in, size_t in_len,
+ struct strbuf *out, size_t out_hint,
+ struct strbuf *err, size_t err_hint)
+{
+ struct io_pump io[3];
+ int nr = 0;
+
+ if (in)
+ cmd->in = -1;
+ if (out)
+ cmd->out = -1;
+ if (err)
+ cmd->err = -1;
+
+ if (start_command(cmd) < 0)
+ return -1;
+
+ if (in) {
+ io[nr].fd = cmd->in;
+ io[nr].type = POLLOUT;
+ io[nr].u.out.buf = in;
+ io[nr].u.out.len = in_len;
+ nr++;
+ }
+ if (out) {
+ io[nr].fd = cmd->out;
+ io[nr].type = POLLIN;
+ io[nr].u.in.buf = out;
+ io[nr].u.in.hint = out_hint;
+ nr++;
+ }
+ if (err) {
+ io[nr].fd = cmd->err;
+ io[nr].type = POLLIN;
+ io[nr].u.in.buf = err;
+ io[nr].u.in.hint = err_hint;
+ nr++;
+ }
+
+ if (pump_io(io, nr) < 0) {
+ finish_command(cmd); /* throw away exit code */
+ return -1;
+ }
+
+ return finish_command(cmd);
+}
+
+enum child_state {
+ GIT_CP_FREE,
+ GIT_CP_WORKING,
+ GIT_CP_WAIT_CLEANUP,
+};
+
+struct parallel_processes {
+ void *data;
+
+ int max_processes;
+ int nr_processes;
+
+ get_next_task_fn get_next_task;
+ start_failure_fn start_failure;
+ task_finished_fn task_finished;
+
+ struct {
+ enum child_state state;
+ struct child_process process;
+ struct strbuf err;
+ void *data;
+ } *children;
+ /*
+ * The struct pollfd is logically part of *children,
+ * but the system call expects it as its own array.
+ */
+ struct pollfd *pfd;
+
+ unsigned shutdown : 1;
+
+ int output_owner;
+ struct strbuf buffered_output; /* of finished children */
+};
+
+static int default_start_failure(struct strbuf *out,
+ void *pp_cb,
+ void *pp_task_cb)
+{
+ return 0;
+}
+
+static int default_task_finished(int result,
+ struct strbuf *out,
+ void *pp_cb,
+ void *pp_task_cb)
+{
+ return 0;
+}
+
+static void kill_children(struct parallel_processes *pp, int signo)
+{
+ int i, n = pp->max_processes;
+
+ for (i = 0; i < n; i++)
+ if (pp->children[i].state == GIT_CP_WORKING)
+ kill(pp->children[i].process.pid, signo);
+}
+
+static struct parallel_processes *pp_for_signal;
+
+static void handle_children_on_signal(int signo)
+{
+ kill_children(pp_for_signal, signo);
+ sigchain_pop(signo);
+ raise(signo);
+}
+
+static void pp_init(struct parallel_processes *pp,
+ int n,
+ get_next_task_fn get_next_task,
+ start_failure_fn start_failure,
+ task_finished_fn task_finished,
+ void *data)
+{
+ int i;
+
+ if (n < 1)
+ n = online_cpus();
+
+ pp->max_processes = n;
+
+ trace_printf("run_processes_parallel: preparing to run up to %d tasks", n);
+
+ pp->data = data;
+ if (!get_next_task)
+ die("BUG: you need to specify a get_next_task function");
+ pp->get_next_task = get_next_task;
+
+ pp->start_failure = start_failure ? start_failure : default_start_failure;
+ pp->task_finished = task_finished ? task_finished : default_task_finished;
+
+ pp->nr_processes = 0;
+ pp->output_owner = 0;
+ pp->shutdown = 0;
+ pp->children = xcalloc(n, sizeof(*pp->children));
+ pp->pfd = xcalloc(n, sizeof(*pp->pfd));
+ strbuf_init(&pp->buffered_output, 0);
+
+ for (i = 0; i < n; i++) {
+ strbuf_init(&pp->children[i].err, 0);
+ child_process_init(&pp->children[i].process);
+ pp->pfd[i].events = POLLIN | POLLHUP;
+ pp->pfd[i].fd = -1;
+ }
+
+ pp_for_signal = pp;
+ sigchain_push_common(handle_children_on_signal);
+}
+
+static void pp_cleanup(struct parallel_processes *pp)
+{
+ int i;
+
+ trace_printf("run_processes_parallel: done");
+ for (i = 0; i < pp->max_processes; i++) {
+ strbuf_release(&pp->children[i].err);
+ child_process_clear(&pp->children[i].process);
+ }
+
+ free(pp->children);
+ free(pp->pfd);
+
+ /*
+ * When get_next_task added messages to the buffer in its last
+ * iteration, the buffered output is non empty.
+ */
+ strbuf_write(&pp->buffered_output, stderr);
+ strbuf_release(&pp->buffered_output);
+
+ sigchain_pop_common();
+}
+
+/* returns
+ * 0 if a new task was started.
+ * 1 if no new jobs was started (get_next_task ran out of work, non critical
+ * problem with starting a new command)
+ * <0 no new job was started, user wishes to shutdown early. Use negative code
+ * to signal the children.
+ */
+static int pp_start_one(struct parallel_processes *pp)
+{
+ int i, code;
+
+ for (i = 0; i < pp->max_processes; i++)
+ if (pp->children[i].state == GIT_CP_FREE)
+ break;
+ if (i == pp->max_processes)
+ die("BUG: bookkeeping is hard");
+
+ code = pp->get_next_task(&pp->children[i].process,
+ &pp->children[i].err,
+ pp->data,
+ &pp->children[i].data);
+ if (!code) {
+ strbuf_addbuf(&pp->buffered_output, &pp->children[i].err);
+ strbuf_reset(&pp->children[i].err);
+ return 1;
+ }
+ pp->children[i].process.err = -1;
+ pp->children[i].process.stdout_to_stderr = 1;
+ pp->children[i].process.no_stdin = 1;
+
+ if (start_command(&pp->children[i].process)) {
+ code = pp->start_failure(&pp->children[i].err,
+ pp->data,
+ &pp->children[i].data);
+ strbuf_addbuf(&pp->buffered_output, &pp->children[i].err);
+ strbuf_reset(&pp->children[i].err);
+ if (code)
+ pp->shutdown = 1;
+ return code;
+ }
+
+ pp->nr_processes++;
+ pp->children[i].state = GIT_CP_WORKING;
+ pp->pfd[i].fd = pp->children[i].process.err;
+ return 0;
+}
+
+static void pp_buffer_stderr(struct parallel_processes *pp, int output_timeout)
+{
+ int i;
+
+ while ((i = poll(pp->pfd, pp->max_processes, output_timeout)) < 0) {
+ if (errno == EINTR)
+ continue;
+ pp_cleanup(pp);
+ die_errno("poll");
+ }
+
+ /* Buffer output from all pipes. */
+ for (i = 0; i < pp->max_processes; i++) {
+ if (pp->children[i].state == GIT_CP_WORKING &&
+ pp->pfd[i].revents & (POLLIN | POLLHUP)) {
+ int n = strbuf_read_once(&pp->children[i].err,
+ pp->children[i].process.err, 0);
+ if (n == 0) {
+ close(pp->children[i].process.err);
+ pp->children[i].state = GIT_CP_WAIT_CLEANUP;
+ } else if (n < 0)
+ if (errno != EAGAIN)
+ die_errno("read");
+ }
+ }
+}
+
+static void pp_output(struct parallel_processes *pp)
+{
+ int i = pp->output_owner;
+ if (pp->children[i].state == GIT_CP_WORKING &&
+ pp->children[i].err.len) {
+ strbuf_write(&pp->children[i].err, stderr);
+ strbuf_reset(&pp->children[i].err);
+ }
+}
+
+static int pp_collect_finished(struct parallel_processes *pp)
+{
+ int i, code;
+ int n = pp->max_processes;
+ int result = 0;
+
+ while (pp->nr_processes > 0) {
+ for (i = 0; i < pp->max_processes; i++)
+ if (pp->children[i].state == GIT_CP_WAIT_CLEANUP)
+ break;
+ if (i == pp->max_processes)
+ break;
+
+ code = finish_command(&pp->children[i].process);
+
+ code = pp->task_finished(code,
+ &pp->children[i].err, pp->data,
+ &pp->children[i].data);
+
+ if (code)
+ result = code;
+ if (code < 0)
+ break;
+
+ pp->nr_processes--;
+ pp->children[i].state = GIT_CP_FREE;
+ pp->pfd[i].fd = -1;
+ child_process_init(&pp->children[i].process);
+
+ if (i != pp->output_owner) {
+ strbuf_addbuf(&pp->buffered_output, &pp->children[i].err);
+ strbuf_reset(&pp->children[i].err);
+ } else {
+ strbuf_write(&pp->children[i].err, stderr);
+ strbuf_reset(&pp->children[i].err);
+
+ /* Output all other finished child processes */
+ strbuf_write(&pp->buffered_output, stderr);
+ strbuf_reset(&pp->buffered_output);
+
+ /*
+ * Pick next process to output live.
+ * NEEDSWORK:
+ * For now we pick it randomly by doing a round
+ * robin. Later we may want to pick the one with
+ * the most output or the longest or shortest
+ * running process time.
+ */
+ for (i = 0; i < n; i++)
+ if (pp->children[(pp->output_owner + i) % n].state == GIT_CP_WORKING)
+ break;
+ pp->output_owner = (pp->output_owner + i) % n;
+ }
+ }
+ return result;
+}
+
+int run_processes_parallel(int n,
+ get_next_task_fn get_next_task,
+ start_failure_fn start_failure,
+ task_finished_fn task_finished,
+ void *pp_cb)
+{
+ int i, code;
+ int output_timeout = 100;
+ int spawn_cap = 4;
+ struct parallel_processes pp;
+
+ pp_init(&pp, n, get_next_task, start_failure, task_finished, pp_cb);
+ while (1) {
+ for (i = 0;
+ i < spawn_cap && !pp.shutdown &&
+ pp.nr_processes < pp.max_processes;
+ i++) {
+ code = pp_start_one(&pp);
+ if (!code)
+ continue;
+ if (code < 0) {
+ pp.shutdown = 1;
+ kill_children(&pp, -code);
+ }
+ break;
+ }
+ if (!pp.nr_processes)
+ break;
+ pp_buffer_stderr(&pp, output_timeout);
+ pp_output(&pp);
+ code = pp_collect_finished(&pp);
+ if (code) {
+ pp.shutdown = 1;
+ if (code < 0)
+ kill_children(&pp, -code);
+ }
+ }
+
+ pp_cleanup(&pp);
+ return 0;
+}