#include "cache.h" #include "run-command.h" #include "exec_cmd.h" static inline void close_pair(int fd[2]) { close(fd[0]); close(fd[1]); } static inline void dup_devnull(int to) { int fd = open("/dev/null", O_RDWR); dup2(fd, to); close(fd); } int start_command(struct child_process *cmd) { int need_in, need_out, need_err; int fdin[2], fdout[2], fderr[2]; /* * In case of errors we must keep the promise to close FDs * that have been passed in via ->in and ->out. */ need_in = !cmd->no_stdin && cmd->in < 0; if (need_in) { if (pipe(fdin) < 0) { if (cmd->out > 0) close(cmd->out); return -ERR_RUN_COMMAND_PIPE; } cmd->in = fdin[1]; } need_out = !cmd->no_stdout && !cmd->stdout_to_stderr && cmd->out < 0; if (need_out) { if (pipe(fdout) < 0) { if (need_in) close_pair(fdin); else if (cmd->in) close(cmd->in); return -ERR_RUN_COMMAND_PIPE; } cmd->out = fdout[0]; } need_err = !cmd->no_stderr && cmd->err < 0; if (need_err) { if (pipe(fderr) < 0) { if (need_in) close_pair(fdin); else if (cmd->in) close(cmd->in); if (need_out) close_pair(fdout); else if (cmd->out) close(cmd->out); return -ERR_RUN_COMMAND_PIPE; } cmd->err = fderr[0]; } #ifndef __MINGW32__ cmd->pid = fork(); if (!cmd->pid) { if (cmd->no_stdin) dup_devnull(0); else if (need_in) { dup2(fdin[0], 0); close_pair(fdin); } else if (cmd->in) { dup2(cmd->in, 0); close(cmd->in); } if (cmd->no_stderr) dup_devnull(2); else if (need_err) { dup2(fderr[1], 2); close_pair(fderr); } if (cmd->no_stdout) dup_devnull(1); else if (cmd->stdout_to_stderr) dup2(2, 1); else if (need_out) { dup2(fdout[1], 1); close_pair(fdout); } else if (cmd->out > 1) { dup2(cmd->out, 1); close(cmd->out); } if (cmd->dir && chdir(cmd->dir)) die("exec %s: cd to %s failed (%s)", cmd->argv[0], cmd->dir, strerror(errno)); if (cmd->env) { for (; *cmd->env; cmd->env++) { if (strchr(*cmd->env, '=')) putenv((char*)*cmd->env); else unsetenv(*cmd->env); } } if (cmd->git_cmd) { execv_git_cmd(cmd->argv); } else { execvp(cmd->argv[0], (char *const*) cmd->argv); } die("exec %s failed.", cmd->argv[0]); } #else int s0 = -1, s1 = -1, s2 = -1; /* backups of stdin, stdout, stderr */ const char *sargv0 = cmd->argv[0]; char **env = environ; struct strbuf git_cmd; 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->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->git_cmd) { strbuf_init(&git_cmd, 0); strbuf_addf(&git_cmd, "git-%s", cmd->argv[0]); cmd->argv[0] = git_cmd.buf; } cmd->pid = spawnvpe(_P_NOWAIT, cmd->argv[0], cmd->argv, (const char **)env); if (cmd->env) free_environ(env); if (cmd->git_cmd) strbuf_release(&git_cmd); cmd->argv[0] = sargv0; if (s0 >= 0) dup2(s0, 0), close(s0); if (s1 >= 0) dup2(s1, 1), close(s1); if (s2 >= 0) dup2(s2, 2), close(s2); #endif if (cmd->pid < 0) { if (need_in) close_pair(fdin); else if (cmd->in) close(cmd->in); if (need_out) close_pair(fdout); else if (cmd->out) close(cmd->out); if (need_err) close_pair(fderr); return -ERR_RUN_COMMAND_FORK; } if (need_in) close(fdin[0]); else if (cmd->in) close(cmd->in); if (need_out) close(fdout[1]); else if (cmd->out) close(cmd->out); if (need_err) close(fderr[1]); return 0; } static int wait_or_whine(pid_t pid) { 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 finish_command(struct child_process *cmd) { return wait_or_whine(cmd->pid); } int run_command(struct child_process *cmd) { int 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) { 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; } int run_command_v_opt(const char **argv, int opt) { struct child_process cmd; prepare_run_command_v_opt(&cmd, argv, opt); return run_command(&cmd); } int run_command_v_opt_cd(const char **argv, int opt, const char *dir) { struct child_process cmd; prepare_run_command_v_opt(&cmd, argv, opt); cmd.dir = dir; return run_command(&cmd); } 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); cmd.dir = dir; cmd.env = env; return run_command(&cmd); } #ifdef __MINGW32__ static __stdcall unsigned run_thread(void *data) { struct async *async = data; return async->proc(async->fd_for_proc, async->data); } #endif int start_async(struct async *async) { int pipe_out[2]; if (pipe(pipe_out) < 0) return error("cannot create pipe: %s", strerror(errno)); async->out = pipe_out[0]; #ifndef __MINGW32__ async->pid = fork(); if (async->pid < 0) { error("fork (async) failed: %s", strerror(errno)); close_pair(pipe_out); return -1; } if (!async->pid) { close(pipe_out[0]); exit(!!async->proc(pipe_out[1], async->data)); } close(pipe_out[1]); #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; } #endif return 0; } int finish_async(struct async *async) { #ifndef __MINGW32__ int ret = 0; if (wait_or_whine(async->pid)) ret = error("waitpid (async) failed"); #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); #endif return ret; }