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#ifndef RUN_COMMAND_H
#define RUN_COMMAND_H
#ifndef NO_PTHREADS
#include <pthread.h>
#endif
#include "argv-array.h"
struct child_process {
const char **argv;
struct argv_array args;
struct argv_array env_array;
pid_t pid;
/*
* Using .in, .out, .err:
* - Specify 0 for no redirections (child inherits stdin, stdout,
* stderr from parent).
* - Specify -1 to have a pipe allocated as follows:
* .in: returns the writable pipe end; parent writes to it,
* the readable pipe end becomes child's stdin
* .out, .err: returns the readable pipe end; parent reads from
* it, the writable pipe end becomes child's stdout/stderr
* The caller of start_command() must close the returned FDs
* after it has completed reading from/writing to it!
* - Specify > 0 to set a channel to a particular FD as follows:
* .in: a readable FD, becomes child's stdin
* .out: a writable FD, becomes child's stdout/stderr
* .err: a writable FD, becomes child's stderr
* The specified FD is closed by start_command(), even in case
* of errors!
*/
int in;
int out;
int err;
const char *dir;
const char *const *env;
unsigned no_stdin:1;
unsigned no_stdout:1;
unsigned no_stderr:1;
unsigned git_cmd:1; /* if this is to be git sub-command */
unsigned silent_exec_failure:1;
unsigned stdout_to_stderr:1;
unsigned use_shell:1;
unsigned clean_on_exit:1;
};
#define CHILD_PROCESS_INIT { NULL, ARGV_ARRAY_INIT, ARGV_ARRAY_INIT }
void child_process_init(struct child_process *);
void child_process_clear(struct child_process *);
int start_command(struct child_process *);
int finish_command(struct child_process *);
int finish_command_in_signal(struct child_process *);
int run_command(struct child_process *);
/*
* Returns the path to the hook file, or NULL if the hook is missing
* or disabled. Note that this points to static storage that will be
* overwritten by further calls to find_hook and run_hook_*.
*/
extern const char *find_hook(const char *name);
LAST_ARG_MUST_BE_NULL
extern int run_hook_le(const char *const *env, const char *name, ...);
extern int run_hook_ve(const char *const *env, const char *name, va_list args);
#define RUN_COMMAND_NO_STDIN 1
#define RUN_GIT_CMD 2 /*If this is to be git sub-command */
#define RUN_COMMAND_STDOUT_TO_STDERR 4
#define RUN_SILENT_EXEC_FAILURE 8
#define RUN_USING_SHELL 16
#define RUN_CLEAN_ON_EXIT 32
int run_command_v_opt(const char **argv, int opt);
/*
* env (the environment) is to be formatted like environ: "VAR=VALUE".
* To unset an environment variable use just "VAR".
*/
int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env);
/**
* Execute the given command, capturing its stdout in the given strbuf.
* Returns -1 if starting the command fails or reading fails, and otherwise
* returns the exit code of the command. The output collected in the
* buffer is kept even if the command returns a non-zero exit. The hint field
* gives a starting size for the strbuf allocation.
*
* The fields of "cmd" should be set up as they would for a normal run_command
* invocation. But note that there is no need to set cmd->out; the function
* sets it up for the caller.
*/
int capture_command(struct child_process *cmd, struct strbuf *buf, size_t hint);
/*
* The purpose of the following functions is to feed a pipe by running
* a function asynchronously and providing output that the caller reads.
*
* It is expected that no synchronization and mutual exclusion between
* the caller and the feed function is necessary so that the function
* can run in a thread without interfering with the caller.
*/
struct async {
/*
* proc reads from in; closes it before return
* proc writes to out; closes it before return
* returns 0 on success, non-zero on failure
*/
int (*proc)(int in, int out, void *data);
void *data;
int in; /* caller writes here and closes it */
int out; /* caller reads from here and closes it */
#ifdef NO_PTHREADS
pid_t pid;
#else
pthread_t tid;
int proc_in;
int proc_out;
#endif
};
int start_async(struct async *async);
int finish_async(struct async *async);
int in_async(void);
void NORETURN async_exit(int code);
/**
* This callback should initialize the child process and preload the
* error channel if desired. The preloading of is useful if you want to
* have a message printed directly before the output of the child process.
* pp_cb is the callback cookie as passed to run_processes_parallel.
* You can store a child process specific callback cookie in pp_task_cb.
*
* Even after returning 0 to indicate that there are no more processes,
* this function will be called again until there are no more running
* child processes.
*
* Return 1 if the next child is ready to run.
* Return 0 if there are currently no more tasks to be processed.
* To send a signal to other child processes for abortion,
* return the negative signal number.
*/
typedef int (*get_next_task_fn)(struct child_process *cp,
struct strbuf *err,
void *pp_cb,
void **pp_task_cb);
/**
* This callback is called whenever there are problems starting
* a new process.
*
* You must not write to stdout or stderr in this function. Add your
* message to the strbuf err instead, which will be printed without
* messing up the output of the other parallel processes.
*
* pp_cb is the callback cookie as passed into run_processes_parallel,
* pp_task_cb is the callback cookie as passed into get_next_task_fn.
*
* Return 0 to continue the parallel processing. To abort return non zero.
* To send a signal to other child processes for abortion, return
* the negative signal number.
*/
typedef int (*start_failure_fn)(struct child_process *cp,
struct strbuf *err,
void *pp_cb,
void *pp_task_cb);
/**
* This callback is called on every child process that finished processing.
*
* You must not write to stdout or stderr in this function. Add your
* message to the strbuf err instead, which will be printed without
* messing up the output of the other parallel processes.
*
* pp_cb is the callback cookie as passed into run_processes_parallel,
* pp_task_cb is the callback cookie as passed into get_next_task_fn.
*
* Return 0 to continue the parallel processing. To abort return non zero.
* To send a signal to other child processes for abortion, return
* the negative signal number.
*/
typedef int (*task_finished_fn)(int result,
struct child_process *cp,
struct strbuf *err,
void *pp_cb,
void *pp_task_cb);
/**
* Runs up to n processes at the same time. Whenever a process can be
* started, the callback get_next_task_fn is called to obtain the data
* required to start another child process.
*
* The children started via this function run in parallel. Their output
* (both stdout and stderr) is routed to stderr in a manner that output
* from different tasks does not interleave.
*
* If start_failure_fn or task_finished_fn are NULL, default handlers
* will be used. The default handlers will print an error message on
* error without issuing an emergency stop.
*/
int run_processes_parallel(int n,
get_next_task_fn,
start_failure_fn,
task_finished_fn,
void *pp_cb);
#endif
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