start_command(), .in/.out/.err = -1: Callers must close the file descriptor
[git/git.git] / run-command.c
CommitLineData
b1bf95bb
JW
1#include "cache.h"
2#include "run-command.h"
77cb17e9 3#include "exec_cmd.h"
b1bf95bb 4
9dc09c76
SP
5static inline void close_pair(int fd[2])
6{
7 close(fd[0]);
8 close(fd[1]);
9}
10
e4507ae8
SP
11static inline void dup_devnull(int to)
12{
13 int fd = open("/dev/null", O_RDWR);
14 dup2(fd, to);
15 close(fd);
16}
17
ebcb5d16 18int start_command(struct child_process *cmd)
b1bf95bb 19{
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JS
20 int need_in, need_out, need_err;
21 int fdin[2], fdout[2], fderr[2];
4919bf03 22
e4507ae8 23 need_in = !cmd->no_stdin && cmd->in < 0;
4919bf03
SP
24 if (need_in) {
25 if (pipe(fdin) < 0)
26 return -ERR_RUN_COMMAND_PIPE;
27 cmd->in = fdin[1];
4919bf03
SP
28 }
29
e4507ae8
SP
30 need_out = !cmd->no_stdout
31 && !cmd->stdout_to_stderr
32 && cmd->out < 0;
f4bba25b
SP
33 if (need_out) {
34 if (pipe(fdout) < 0) {
35 if (need_in)
36 close_pair(fdin);
37 return -ERR_RUN_COMMAND_PIPE;
38 }
39 cmd->out = fdout[0];
f4bba25b
SP
40 }
41
b73a4397 42 need_err = !cmd->no_stderr && cmd->err < 0;
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43 if (need_err) {
44 if (pipe(fderr) < 0) {
45 if (need_in)
46 close_pair(fdin);
47 if (need_out)
48 close_pair(fdout);
49 return -ERR_RUN_COMMAND_PIPE;
50 }
51 cmd->err = fderr[0];
52 }
53
ebcb5d16 54 cmd->pid = fork();
4919bf03 55 if (cmd->pid < 0) {
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56 if (need_in)
57 close_pair(fdin);
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58 if (need_out)
59 close_pair(fdout);
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60 if (need_err)
61 close_pair(fderr);
b1bf95bb 62 return -ERR_RUN_COMMAND_FORK;
4919bf03
SP
63 }
64
ebcb5d16 65 if (!cmd->pid) {
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SP
66 if (cmd->no_stdin)
67 dup_devnull(0);
68 else if (need_in) {
4919bf03 69 dup2(fdin[0], 0);
9dc09c76 70 close_pair(fdin);
4919bf03
SP
71 } else if (cmd->in) {
72 dup2(cmd->in, 0);
73 close(cmd->in);
95d3c4f5 74 }
4919bf03 75
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SP
76 if (cmd->no_stdout)
77 dup_devnull(1);
78 else if (cmd->stdout_to_stderr)
cd83c74c 79 dup2(2, 1);
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80 else if (need_out) {
81 dup2(fdout[1], 1);
82 close_pair(fdout);
83 } else if (cmd->out > 1) {
84 dup2(cmd->out, 1);
85 close(cmd->out);
86 }
87
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SP
88 if (cmd->no_stderr)
89 dup_devnull(2);
90 else if (need_err) {
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91 dup2(fderr[1], 2);
92 close_pair(fderr);
93 }
94
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AR
95 if (cmd->dir && chdir(cmd->dir))
96 die("exec %s: cd to %s failed (%s)", cmd->argv[0],
97 cmd->dir, strerror(errno));
ee493148 98 if (cmd->env) {
3427b375
AR
99 for (; *cmd->env; cmd->env++) {
100 if (strchr(*cmd->env, '='))
101 putenv((char*)*cmd->env);
102 else
103 unsetenv(*cmd->env);
104 }
ee493148 105 }
f1000898
SP
106 if (cmd->git_cmd) {
107 execv_git_cmd(cmd->argv);
77cb17e9 108 } else {
f1000898 109 execvp(cmd->argv[0], (char *const*) cmd->argv);
128aed68 110 }
f1000898 111 die("exec %s failed.", cmd->argv[0]);
b1bf95bb 112 }
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113
114 if (need_in)
115 close(fdin[0]);
116 else if (cmd->in)
117 close(cmd->in);
118
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119 if (need_out)
120 close(fdout[1]);
121 else if (cmd->out > 1)
122 close(cmd->out);
123
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124 if (need_err)
125 close(fderr[1]);
126
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SP
127 return 0;
128}
129
2d22c208 130static int wait_or_whine(pid_t pid)
ebcb5d16 131{
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JW
132 for (;;) {
133 int status, code;
2d22c208 134 pid_t waiting = waitpid(pid, &status, 0);
b1bf95bb 135
6f002f98 136 if (waiting < 0) {
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JW
137 if (errno == EINTR)
138 continue;
6f002f98 139 error("waitpid failed (%s)", strerror(errno));
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140 return -ERR_RUN_COMMAND_WAITPID;
141 }
2d22c208 142 if (waiting != pid)
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143 return -ERR_RUN_COMMAND_WAITPID_WRONG_PID;
144 if (WIFSIGNALED(status))
145 return -ERR_RUN_COMMAND_WAITPID_SIGNAL;
146
147 if (!WIFEXITED(status))
148 return -ERR_RUN_COMMAND_WAITPID_NOEXIT;
149 code = WEXITSTATUS(status);
150 if (code)
151 return -code;
152 return 0;
153 }
154}
f1000898 155
2d22c208
JS
156int finish_command(struct child_process *cmd)
157{
2d22c208
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158 return wait_or_whine(cmd->pid);
159}
160
ebcb5d16
SP
161int run_command(struct child_process *cmd)
162{
163 int code = start_command(cmd);
164 if (code)
165 return code;
166 return finish_command(cmd);
167}
168
1568fea0 169static void prepare_run_command_v_opt(struct child_process *cmd,
ee493148
AR
170 const char **argv,
171 int opt)
1568fea0
AR
172{
173 memset(cmd, 0, sizeof(*cmd));
174 cmd->argv = argv;
175 cmd->no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0;
176 cmd->git_cmd = opt & RUN_GIT_CMD ? 1 : 0;
177 cmd->stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0;
178}
179
f1000898
SP
180int run_command_v_opt(const char **argv, int opt)
181{
182 struct child_process cmd;
1568fea0
AR
183 prepare_run_command_v_opt(&cmd, argv, opt);
184 return run_command(&cmd);
185}
186
187int run_command_v_opt_cd(const char **argv, int opt, const char *dir)
188{
189 struct child_process cmd;
190 prepare_run_command_v_opt(&cmd, argv, opt);
191 cmd.dir = dir;
f1000898
SP
192 return run_command(&cmd);
193}
ee493148
AR
194
195int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env)
196{
197 struct child_process cmd;
198 prepare_run_command_v_opt(&cmd, argv, opt);
199 cmd.dir = dir;
200 cmd.env = env;
201 return run_command(&cmd);
202}
2d22c208
JS
203
204int start_async(struct async *async)
205{
206 int pipe_out[2];
207
208 if (pipe(pipe_out) < 0)
209 return error("cannot create pipe: %s", strerror(errno));
210
211 async->pid = fork();
212 if (async->pid < 0) {
213 error("fork (async) failed: %s", strerror(errno));
214 close_pair(pipe_out);
215 return -1;
216 }
217 if (!async->pid) {
218 close(pipe_out[0]);
219 exit(!!async->proc(pipe_out[1], async->data));
220 }
221 async->out = pipe_out[0];
222 close(pipe_out[1]);
223 return 0;
224}
225
226int finish_async(struct async *async)
227{
228 int ret = 0;
229
230 if (wait_or_whine(async->pid))
231 ret = error("waitpid (async) failed");
232 return ret;
233}