git-p4: chdir now properly sets PWD environment variable in msysGit
[git/git-p4.git] / run-command.c
blobbbb9c777e583c345d25a6651f9ddf7725c10f6af
1 #include "cache.h"
2 #include "run-command.h"
3 #include "exec_cmd.h"
5 static inline void close_pair(int fd[2])
7 close(fd[0]);
8 close(fd[1]);
11 static inline void dup_devnull(int to)
13 int fd = open("/dev/null", O_RDWR);
14 dup2(fd, to);
15 close(fd);
18 int start_command(struct child_process *cmd)
20 int need_in, need_out, need_err;
21 int fdin[2], fdout[2], fderr[2];
24 * In case of errors we must keep the promise to close FDs
25 * that have been passed in via ->in and ->out.
28 need_in = !cmd->no_stdin && cmd->in < 0;
29 if (need_in) {
30 if (pipe(fdin) < 0) {
31 if (cmd->out > 0)
32 close(cmd->out);
33 return -ERR_RUN_COMMAND_PIPE;
35 cmd->in = fdin[1];
38 need_out = !cmd->no_stdout
39 && !cmd->stdout_to_stderr
40 && cmd->out < 0;
41 if (need_out) {
42 if (pipe(fdout) < 0) {
43 if (need_in)
44 close_pair(fdin);
45 else if (cmd->in)
46 close(cmd->in);
47 return -ERR_RUN_COMMAND_PIPE;
49 cmd->out = fdout[0];
52 need_err = !cmd->no_stderr && cmd->err < 0;
53 if (need_err) {
54 if (pipe(fderr) < 0) {
55 if (need_in)
56 close_pair(fdin);
57 else if (cmd->in)
58 close(cmd->in);
59 if (need_out)
60 close_pair(fdout);
61 else if (cmd->out)
62 close(cmd->out);
63 return -ERR_RUN_COMMAND_PIPE;
65 cmd->err = fderr[0];
68 trace_argv_printf(cmd->argv, "trace: run_command:");
70 #ifndef __MINGW32__
71 fflush(NULL);
72 cmd->pid = fork();
73 if (!cmd->pid) {
74 if (cmd->no_stdin)
75 dup_devnull(0);
76 else if (need_in) {
77 dup2(fdin[0], 0);
78 close_pair(fdin);
79 } else if (cmd->in) {
80 dup2(cmd->in, 0);
81 close(cmd->in);
84 if (cmd->no_stderr)
85 dup_devnull(2);
86 else if (need_err) {
87 dup2(fderr[1], 2);
88 close_pair(fderr);
91 if (cmd->no_stdout)
92 dup_devnull(1);
93 else if (cmd->stdout_to_stderr)
94 dup2(2, 1);
95 else if (need_out) {
96 dup2(fdout[1], 1);
97 close_pair(fdout);
98 } else if (cmd->out > 1) {
99 dup2(cmd->out, 1);
100 close(cmd->out);
103 if (cmd->dir && chdir(cmd->dir))
104 die("exec %s: cd to %s failed (%s)", cmd->argv[0],
105 cmd->dir, strerror(errno));
106 if (cmd->env) {
107 for (; *cmd->env; cmd->env++) {
108 if (strchr(*cmd->env, '='))
109 putenv((char*)*cmd->env);
110 else
111 unsetenv(*cmd->env);
114 if (cmd->git_cmd) {
115 execv_git_cmd(cmd->argv);
116 } else {
117 execvp(cmd->argv[0], (char *const*) cmd->argv);
119 die("exec %s failed.", cmd->argv[0]);
121 #else
122 int s0 = -1, s1 = -1, s2 = -1; /* backups of stdin, stdout, stderr */
123 const char **sargv = cmd->argv;
124 char **env = environ;
126 if (cmd->no_stdin) {
127 s0 = dup(0);
128 dup_devnull(0);
129 } else if (need_in) {
130 s0 = dup(0);
131 dup2(fdin[0], 0);
132 } else if (cmd->in) {
133 s0 = dup(0);
134 dup2(cmd->in, 0);
137 if (cmd->no_stderr) {
138 s2 = dup(2);
139 dup_devnull(2);
140 } else if (need_err) {
141 s2 = dup(2);
142 dup2(fderr[1], 2);
145 if (cmd->no_stdout) {
146 s1 = dup(1);
147 dup_devnull(1);
148 } else if (cmd->stdout_to_stderr) {
149 s1 = dup(1);
150 dup2(2, 1);
151 } else if (need_out) {
152 s1 = dup(1);
153 dup2(fdout[1], 1);
154 } else if (cmd->out > 1) {
155 s1 = dup(1);
156 dup2(cmd->out, 1);
159 if (cmd->dir)
160 die("chdir in start_command() not implemented");
161 if (cmd->env) {
162 env = copy_environ();
163 for (; *cmd->env; cmd->env++)
164 env = env_setenv(env, *cmd->env);
167 if (cmd->git_cmd) {
168 cmd->argv = prepare_git_cmd(cmd->argv);
171 cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, env);
173 if (cmd->env)
174 free_environ(env);
175 if (cmd->git_cmd)
176 free(cmd->argv);
178 cmd->argv = sargv;
179 if (s0 >= 0)
180 dup2(s0, 0), close(s0);
181 if (s1 >= 0)
182 dup2(s1, 1), close(s1);
183 if (s2 >= 0)
184 dup2(s2, 2), close(s2);
185 #endif
187 if (cmd->pid < 0) {
188 if (need_in)
189 close_pair(fdin);
190 else if (cmd->in)
191 close(cmd->in);
192 if (need_out)
193 close_pair(fdout);
194 else if (cmd->out)
195 close(cmd->out);
196 if (need_err)
197 close_pair(fderr);
198 return -ERR_RUN_COMMAND_FORK;
201 if (need_in)
202 close(fdin[0]);
203 else if (cmd->in)
204 close(cmd->in);
206 if (need_out)
207 close(fdout[1]);
208 else if (cmd->out)
209 close(cmd->out);
211 if (need_err)
212 close(fderr[1]);
214 return 0;
217 static int wait_or_whine(pid_t pid)
219 for (;;) {
220 int status, code;
221 pid_t waiting = waitpid(pid, &status, 0);
223 if (waiting < 0) {
224 if (errno == EINTR)
225 continue;
226 error("waitpid failed (%s)", strerror(errno));
227 return -ERR_RUN_COMMAND_WAITPID;
229 if (waiting != pid)
230 return -ERR_RUN_COMMAND_WAITPID_WRONG_PID;
231 if (WIFSIGNALED(status))
232 return -ERR_RUN_COMMAND_WAITPID_SIGNAL;
234 if (!WIFEXITED(status))
235 return -ERR_RUN_COMMAND_WAITPID_NOEXIT;
236 code = WEXITSTATUS(status);
237 if (code)
238 return -code;
239 return 0;
243 int finish_command(struct child_process *cmd)
245 return wait_or_whine(cmd->pid);
248 int run_command(struct child_process *cmd)
250 int code = start_command(cmd);
251 if (code)
252 return code;
253 return finish_command(cmd);
256 static void prepare_run_command_v_opt(struct child_process *cmd,
257 const char **argv,
258 int opt)
260 memset(cmd, 0, sizeof(*cmd));
261 cmd->argv = argv;
262 cmd->no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0;
263 cmd->git_cmd = opt & RUN_GIT_CMD ? 1 : 0;
264 cmd->stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0;
267 int run_command_v_opt(const char **argv, int opt)
269 struct child_process cmd;
270 prepare_run_command_v_opt(&cmd, argv, opt);
271 return run_command(&cmd);
274 int run_command_v_opt_cd(const char **argv, int opt, const char *dir)
276 struct child_process cmd;
277 prepare_run_command_v_opt(&cmd, argv, opt);
278 cmd.dir = dir;
279 return run_command(&cmd);
282 int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env)
284 struct child_process cmd;
285 prepare_run_command_v_opt(&cmd, argv, opt);
286 cmd.dir = dir;
287 cmd.env = env;
288 return run_command(&cmd);
291 #ifdef __MINGW32__
292 static __stdcall unsigned run_thread(void *data)
294 struct async *async = data;
295 return async->proc(async->fd_for_proc, async->data);
297 #endif
299 int start_async(struct async *async)
301 int pipe_out[2];
303 if (pipe(pipe_out) < 0)
304 return error("cannot create pipe: %s", strerror(errno));
305 async->out = pipe_out[0];
307 #ifndef __MINGW32__
308 /* Flush stdio before fork() to avoid cloning buffers */
309 fflush(NULL);
311 async->pid = fork();
312 if (async->pid < 0) {
313 error("fork (async) failed: %s", strerror(errno));
314 close_pair(pipe_out);
315 return -1;
317 if (!async->pid) {
318 close(pipe_out[0]);
319 exit(!!async->proc(pipe_out[1], async->data));
321 close(pipe_out[1]);
322 #else
323 async->fd_for_proc = pipe_out[1];
324 async->tid = (HANDLE) _beginthreadex(NULL, 0, run_thread, async, 0, NULL);
325 if (!async->tid) {
326 error("cannot create thread: %s", strerror(errno));
327 close_pair(pipe_out);
328 return -1;
330 #endif
331 return 0;
334 int finish_async(struct async *async)
336 #ifndef __MINGW32__
337 int ret = 0;
339 if (wait_or_whine(async->pid))
340 ret = error("waitpid (async) failed");
341 #else
342 DWORD ret = 0;
343 if (WaitForSingleObject(async->tid, INFINITE) != WAIT_OBJECT_0)
344 ret = error("waiting for thread failed: %lu", GetLastError());
345 else if (!GetExitCodeThread(async->tid, &ret))
346 ret = error("cannot get thread exit code: %lu", GetLastError());
347 CloseHandle(async->tid);
348 #endif
349 return ret;