#ifndef RUN_COMMAND_H #define RUN_COMMAND_H #include "thread-utils.h" #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; unsigned wait_after_clean:1; void (*clean_on_exit_handler)(struct child_process *process); void *clean_on_exit_handler_cbdata; }; #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 *); extern int is_executable(const char *name); 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, sending "in" to its stdin, and capturing its * stdout and stderr in the "out" and "err" strbufs. Any of the three may * be NULL to skip processing. * * Returns -1 if starting the command fails or reading fails, and otherwise * returns the exit code of the command. Any output collected in the * buffers is kept even if the command returns a non-zero exit. The hint fields * gives starting sizes for the strbuf allocations. * * 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 the in, out, or err * fields; pipe_command handles that automatically. */ int pipe_command(struct child_process *cmd, const char *in, size_t in_len, struct strbuf *out, size_t out_hint, struct strbuf *err, size_t err_hint); /** * Convenience wrapper around pipe_command for the common case * of capturing only stdout. */ static inline int capture_command(struct child_process *cmd, struct strbuf *out, size_t hint) { return pipe_command(cmd, NULL, 0, out, hint, NULL, 0); } /* * 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 isolate_sigpipe; }; int start_async(struct async *async); int finish_async(struct async *async); int in_async(void); int async_with_fork(void); void check_pipe(int err); /** * 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 *out, 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 out 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 strbuf *out, 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 out 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 strbuf *out, 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. * * start_failure_fn and task_finished_fn can be NULL to omit any * special handling. */ int run_processes_parallel(int n, get_next_task_fn, start_failure_fn, task_finished_fn, void *pp_cb); #endif