1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __SUBCMD_RUN_COMMAND_H
3#define __SUBCMD_RUN_COMMAND_H
4
5#include <unistd.h>
6
7enum {
8	ERR_RUN_COMMAND_FORK = 10000,
9	ERR_RUN_COMMAND_EXEC,
10	ERR_RUN_COMMAND_PIPE,
11	ERR_RUN_COMMAND_WAITPID,
12	ERR_RUN_COMMAND_WAITPID_WRONG_PID,
13	ERR_RUN_COMMAND_WAITPID_SIGNAL,
14	ERR_RUN_COMMAND_WAITPID_NOEXIT,
15};
16#define IS_RUN_COMMAND_ERR(x) (-(x) >= ERR_RUN_COMMAND_FORK)
17
18struct child_process {
19	const char **argv;
20	pid_t pid;
21	/*
22	 * Using .in, .out, .err:
23	 * - Specify 0 for no redirections (child inherits stdin, stdout,
24	 *   stderr from parent).
25	 * - Specify -1 to have a pipe allocated as follows:
26	 *     .in: returns the writable pipe end; parent writes to it,
27	 *          the readable pipe end becomes child's stdin
28	 *     .out, .err: returns the readable pipe end; parent reads from
29	 *          it, the writable pipe end becomes child's stdout/stderr
30	 *   The caller of start_command() must close the returned FDs
31	 *   after it has completed reading from/writing to it!
32	 * - Specify > 0 to set a channel to a particular FD as follows:
33	 *     .in: a readable FD, becomes child's stdin
34	 *     .out: a writable FD, becomes child's stdout/stderr
35	 *     .err > 0 not supported
36	 *   The specified FD is closed by start_command(), even in case
37	 *   of errors!
38	 */
39	int in;
40	int out;
41	int err;
42	const char *dir;
43	const char *const *env;
44	unsigned no_stdin:1;
45	unsigned no_stdout:1;
46	unsigned no_stderr:1;
47	unsigned exec_cmd:1; /* if this is to be external sub-command */
48	unsigned stdout_to_stderr:1;
49	void (*preexec_cb)(void);
50	 /* If set, call function in child rather than doing an exec. */
51	int (*no_exec_cmd)(struct child_process *process);
52};
53
54int start_command(struct child_process *);
55int finish_command(struct child_process *);
56int run_command(struct child_process *);
57
58#define RUN_COMMAND_NO_STDIN 1
59#define RUN_EXEC_CMD	     2	/*If this is to be external sub-command */
60#define RUN_COMMAND_STDOUT_TO_STDERR 4
61int run_command_v_opt(const char **argv, int opt);
62
63#endif /* __SUBCMD_RUN_COMMAND_H */
64