Merge branch 'ma/update-hooks-sample-typofix'
[git/gitweb.git] / run-command.h
blob42917e8618ea469ff56d52704794b6e3bc86cf97
1 #ifndef RUN_COMMAND_H
2 #define RUN_COMMAND_H
4 #ifndef NO_PTHREADS
5 #include <pthread.h>
6 #endif
8 #include "argv-array.h"
10 struct child_process {
11 const char **argv;
12 struct argv_array args;
13 struct argv_array env_array;
14 pid_t pid;
16 * Using .in, .out, .err:
17 * - Specify 0 for no redirections (child inherits stdin, stdout,
18 * stderr from parent).
19 * - Specify -1 to have a pipe allocated as follows:
20 * .in: returns the writable pipe end; parent writes to it,
21 * the readable pipe end becomes child's stdin
22 * .out, .err: returns the readable pipe end; parent reads from
23 * it, the writable pipe end becomes child's stdout/stderr
24 * The caller of start_command() must close the returned FDs
25 * after it has completed reading from/writing to it!
26 * - Specify > 0 to set a channel to a particular FD as follows:
27 * .in: a readable FD, becomes child's stdin
28 * .out: a writable FD, becomes child's stdout/stderr
29 * .err: a writable FD, becomes child's stderr
30 * The specified FD is closed by start_command(), even in case
31 * of errors!
33 int in;
34 int out;
35 int err;
36 const char *dir;
37 const char *const *env;
38 unsigned no_stdin:1;
39 unsigned no_stdout:1;
40 unsigned no_stderr:1;
41 unsigned git_cmd:1; /* if this is to be git sub-command */
42 unsigned silent_exec_failure:1;
43 unsigned stdout_to_stderr:1;
44 unsigned use_shell:1;
45 unsigned clean_on_exit:1;
48 #define CHILD_PROCESS_INIT { NULL, ARGV_ARRAY_INIT, ARGV_ARRAY_INIT }
49 void child_process_init(struct child_process *);
50 void child_process_clear(struct child_process *);
52 int start_command(struct child_process *);
53 int finish_command(struct child_process *);
54 int finish_command_in_signal(struct child_process *);
55 int run_command(struct child_process *);
58 * Returns the path to the hook file, or NULL if the hook is missing
59 * or disabled. Note that this points to static storage that will be
60 * overwritten by further calls to find_hook and run_hook_*.
62 extern const char *find_hook(const char *name);
63 LAST_ARG_MUST_BE_NULL
64 extern int run_hook_le(const char *const *env, const char *name, ...);
65 extern int run_hook_ve(const char *const *env, const char *name, va_list args);
67 #define RUN_COMMAND_NO_STDIN 1
68 #define RUN_GIT_CMD 2 /*If this is to be git sub-command */
69 #define RUN_COMMAND_STDOUT_TO_STDERR 4
70 #define RUN_SILENT_EXEC_FAILURE 8
71 #define RUN_USING_SHELL 16
72 #define RUN_CLEAN_ON_EXIT 32
73 int run_command_v_opt(const char **argv, int opt);
76 * env (the environment) is to be formatted like environ: "VAR=VALUE".
77 * To unset an environment variable use just "VAR".
79 int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env);
81 /**
82 * Execute the given command, capturing its stdout in the given strbuf.
83 * Returns -1 if starting the command fails or reading fails, and otherwise
84 * returns the exit code of the command. The output collected in the
85 * buffer is kept even if the command returns a non-zero exit. The hint field
86 * gives a starting size for the strbuf allocation.
88 * The fields of "cmd" should be set up as they would for a normal run_command
89 * invocation. But note that there is no need to set cmd->out; the function
90 * sets it up for the caller.
92 int capture_command(struct child_process *cmd, struct strbuf *buf, size_t hint);
95 * The purpose of the following functions is to feed a pipe by running
96 * a function asynchronously and providing output that the caller reads.
98 * It is expected that no synchronization and mutual exclusion between
99 * the caller and the feed function is necessary so that the function
100 * can run in a thread without interfering with the caller.
102 struct async {
104 * proc reads from in; closes it before return
105 * proc writes to out; closes it before return
106 * returns 0 on success, non-zero on failure
108 int (*proc)(int in, int out, void *data);
109 void *data;
110 int in; /* caller writes here and closes it */
111 int out; /* caller reads from here and closes it */
112 #ifdef NO_PTHREADS
113 pid_t pid;
114 #else
115 pthread_t tid;
116 int proc_in;
117 int proc_out;
118 #endif
121 int start_async(struct async *async);
122 int finish_async(struct async *async);
123 int in_async(void);
124 void NORETURN async_exit(int code);
127 * This callback should initialize the child process and preload the
128 * error channel if desired. The preloading of is useful if you want to
129 * have a message printed directly before the output of the child process.
130 * pp_cb is the callback cookie as passed to run_processes_parallel.
131 * You can store a child process specific callback cookie in pp_task_cb.
133 * Even after returning 0 to indicate that there are no more processes,
134 * this function will be called again until there are no more running
135 * child processes.
137 * Return 1 if the next child is ready to run.
138 * Return 0 if there are currently no more tasks to be processed.
139 * To send a signal to other child processes for abortion,
140 * return the negative signal number.
142 typedef int (*get_next_task_fn)(struct child_process *cp,
143 struct strbuf *err,
144 void *pp_cb,
145 void **pp_task_cb);
148 * This callback is called whenever there are problems starting
149 * a new process.
151 * You must not write to stdout or stderr in this function. Add your
152 * message to the strbuf err instead, which will be printed without
153 * messing up the output of the other parallel processes.
155 * pp_cb is the callback cookie as passed into run_processes_parallel,
156 * pp_task_cb is the callback cookie as passed into get_next_task_fn.
158 * Return 0 to continue the parallel processing. To abort return non zero.
159 * To send a signal to other child processes for abortion, return
160 * the negative signal number.
162 typedef int (*start_failure_fn)(struct child_process *cp,
163 struct strbuf *err,
164 void *pp_cb,
165 void *pp_task_cb);
168 * This callback is called on every child process that finished processing.
170 * You must not write to stdout or stderr in this function. Add your
171 * message to the strbuf err instead, which will be printed without
172 * messing up the output of the other parallel processes.
174 * pp_cb is the callback cookie as passed into run_processes_parallel,
175 * pp_task_cb is the callback cookie as passed into get_next_task_fn.
177 * Return 0 to continue the parallel processing. To abort return non zero.
178 * To send a signal to other child processes for abortion, return
179 * the negative signal number.
181 typedef int (*task_finished_fn)(int result,
182 struct child_process *cp,
183 struct strbuf *err,
184 void *pp_cb,
185 void *pp_task_cb);
188 * Runs up to n processes at the same time. Whenever a process can be
189 * started, the callback get_next_task_fn is called to obtain the data
190 * required to start another child process.
192 * The children started via this function run in parallel. Their output
193 * (both stdout and stderr) is routed to stderr in a manner that output
194 * from different tasks does not interleave.
196 * If start_failure_fn or task_finished_fn are NULL, default handlers
197 * will be used. The default handlers will print an error message on
198 * error without issuing an emergency stop.
200 int run_processes_parallel(int n,
201 get_next_task_fn,
202 start_failure_fn,
203 task_finished_fn,
204 void *pp_cb);
206 #endif