Git 2.21-rc2
[git.git] / run-command.h
blob68f5369fc2d432e8b4b504e9625b541056814216
1 #ifndef RUN_COMMAND_H
2 #define RUN_COMMAND_H
4 #include "thread-utils.h"
6 #include "argv-array.h"
8 struct child_process {
9 const char **argv;
10 struct argv_array args;
11 struct argv_array env_array;
12 pid_t pid;
14 * Using .in, .out, .err:
15 * - Specify 0 for no redirections (child inherits stdin, stdout,
16 * stderr from parent).
17 * - Specify -1 to have a pipe allocated as follows:
18 * .in: returns the writable pipe end; parent writes to it,
19 * the readable pipe end becomes child's stdin
20 * .out, .err: returns the readable pipe end; parent reads from
21 * it, the writable pipe end becomes child's stdout/stderr
22 * The caller of start_command() must close the returned FDs
23 * after it has completed reading from/writing to it!
24 * - Specify > 0 to set a channel to a particular FD as follows:
25 * .in: a readable FD, becomes child's stdin
26 * .out: a writable FD, becomes child's stdout/stderr
27 * .err: a writable FD, becomes child's stderr
28 * The specified FD is closed by start_command(), even in case
29 * of errors!
31 int in;
32 int out;
33 int err;
34 const char *dir;
35 const char *const *env;
36 unsigned no_stdin:1;
37 unsigned no_stdout:1;
38 unsigned no_stderr:1;
39 unsigned git_cmd:1; /* if this is to be git sub-command */
40 unsigned silent_exec_failure:1;
41 unsigned stdout_to_stderr:1;
42 unsigned use_shell:1;
43 unsigned clean_on_exit:1;
44 unsigned wait_after_clean:1;
45 void (*clean_on_exit_handler)(struct child_process *process);
46 void *clean_on_exit_handler_cbdata;
49 #define CHILD_PROCESS_INIT { NULL, ARGV_ARRAY_INIT, ARGV_ARRAY_INIT }
50 void child_process_init(struct child_process *);
51 void child_process_clear(struct child_process *);
52 extern int is_executable(const char *name);
54 int start_command(struct child_process *);
55 int finish_command(struct child_process *);
56 int finish_command_in_signal(struct child_process *);
57 int run_command(struct child_process *);
60 * Returns the path to the hook file, or NULL if the hook is missing
61 * or disabled. Note that this points to static storage that will be
62 * overwritten by further calls to find_hook and run_hook_*.
64 extern const char *find_hook(const char *name);
65 LAST_ARG_MUST_BE_NULL
66 extern int run_hook_le(const char *const *env, const char *name, ...);
67 extern int run_hook_ve(const char *const *env, const char *name, va_list args);
69 #define RUN_COMMAND_NO_STDIN 1
70 #define RUN_GIT_CMD 2 /*If this is to be git sub-command */
71 #define RUN_COMMAND_STDOUT_TO_STDERR 4
72 #define RUN_SILENT_EXEC_FAILURE 8
73 #define RUN_USING_SHELL 16
74 #define RUN_CLEAN_ON_EXIT 32
75 int run_command_v_opt(const char **argv, int opt);
78 * env (the environment) is to be formatted like environ: "VAR=VALUE".
79 * To unset an environment variable use just "VAR".
81 int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env);
83 /**
84 * Execute the given command, sending "in" to its stdin, and capturing its
85 * stdout and stderr in the "out" and "err" strbufs. Any of the three may
86 * be NULL to skip processing.
88 * Returns -1 if starting the command fails or reading fails, and otherwise
89 * returns the exit code of the command. Any output collected in the
90 * buffers is kept even if the command returns a non-zero exit. The hint fields
91 * gives starting sizes for the strbuf allocations.
93 * The fields of "cmd" should be set up as they would for a normal run_command
94 * invocation. But note that there is no need to set the in, out, or err
95 * fields; pipe_command handles that automatically.
97 int pipe_command(struct child_process *cmd,
98 const char *in, size_t in_len,
99 struct strbuf *out, size_t out_hint,
100 struct strbuf *err, size_t err_hint);
103 * Convenience wrapper around pipe_command for the common case
104 * of capturing only stdout.
106 static inline int capture_command(struct child_process *cmd,
107 struct strbuf *out,
108 size_t hint)
110 return pipe_command(cmd, NULL, 0, out, hint, NULL, 0);
114 * The purpose of the following functions is to feed a pipe by running
115 * a function asynchronously and providing output that the caller reads.
117 * It is expected that no synchronization and mutual exclusion between
118 * the caller and the feed function is necessary so that the function
119 * can run in a thread without interfering with the caller.
121 struct async {
123 * proc reads from in; closes it before return
124 * proc writes to out; closes it before return
125 * returns 0 on success, non-zero on failure
127 int (*proc)(int in, int out, void *data);
128 void *data;
129 int in; /* caller writes here and closes it */
130 int out; /* caller reads from here and closes it */
131 #ifdef NO_PTHREADS
132 pid_t pid;
133 #else
134 pthread_t tid;
135 int proc_in;
136 int proc_out;
137 #endif
138 int isolate_sigpipe;
141 int start_async(struct async *async);
142 int finish_async(struct async *async);
143 int in_async(void);
144 int async_with_fork(void);
145 void check_pipe(int err);
148 * This callback should initialize the child process and preload the
149 * error channel if desired. The preloading of is useful if you want to
150 * have a message printed directly before the output of the child process.
151 * pp_cb is the callback cookie as passed to run_processes_parallel.
152 * You can store a child process specific callback cookie in pp_task_cb.
154 * Even after returning 0 to indicate that there are no more processes,
155 * this function will be called again until there are no more running
156 * child processes.
158 * Return 1 if the next child is ready to run.
159 * Return 0 if there are currently no more tasks to be processed.
160 * To send a signal to other child processes for abortion,
161 * return the negative signal number.
163 typedef int (*get_next_task_fn)(struct child_process *cp,
164 struct strbuf *out,
165 void *pp_cb,
166 void **pp_task_cb);
169 * This callback is called whenever there are problems starting
170 * a new process.
172 * You must not write to stdout or stderr in this function. Add your
173 * message to the strbuf out instead, which will be printed without
174 * messing up the output of the other parallel processes.
176 * pp_cb is the callback cookie as passed into run_processes_parallel,
177 * pp_task_cb is the callback cookie as passed into get_next_task_fn.
179 * Return 0 to continue the parallel processing. To abort return non zero.
180 * To send a signal to other child processes for abortion, return
181 * the negative signal number.
183 typedef int (*start_failure_fn)(struct strbuf *out,
184 void *pp_cb,
185 void *pp_task_cb);
188 * This callback is called on every child process that finished processing.
190 * You must not write to stdout or stderr in this function. Add your
191 * message to the strbuf out instead, which will be printed without
192 * messing up the output of the other parallel processes.
194 * pp_cb is the callback cookie as passed into run_processes_parallel,
195 * pp_task_cb is the callback cookie as passed into get_next_task_fn.
197 * Return 0 to continue the parallel processing. To abort return non zero.
198 * To send a signal to other child processes for abortion, return
199 * the negative signal number.
201 typedef int (*task_finished_fn)(int result,
202 struct strbuf *out,
203 void *pp_cb,
204 void *pp_task_cb);
207 * Runs up to n processes at the same time. Whenever a process can be
208 * started, the callback get_next_task_fn is called to obtain the data
209 * required to start another child process.
211 * The children started via this function run in parallel. Their output
212 * (both stdout and stderr) is routed to stderr in a manner that output
213 * from different tasks does not interleave.
215 * start_failure_fn and task_finished_fn can be NULL to omit any
216 * special handling.
218 int run_processes_parallel(int n,
219 get_next_task_fn,
220 start_failure_fn,
221 task_finished_fn,
222 void *pp_cb);
224 #endif