mpv/osdep/subprocess.h

89 lines
3.5 KiB
C

/*
* This file is part of mpv.
*
* mpv is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* mpv is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef MP_SUBPROCESS_H_
#define MP_SUBPROCESS_H_
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include "misc/bstr.h"
struct mp_cancel;
// Incrementally called with data that was read. Buffer valid only during call.
// size==0 means EOF.
typedef void (*subprocess_read_cb)(void *ctx, char *data, size_t size);
// Incrementally called to refill *mp_subprocess_fd.write_buf, whenever write_buf
// has length 0 and the pipe is writable. While writing, *write_buf is adjusted
// to contain only the not yet written data.
// Not filling the buffer means EOF.
typedef void (*subprocess_write_cb)(void *ctx);
void mp_devnull(void *ctx, char *data, size_t size);
#define MP_SUBPROCESS_MAX_FDS 10
struct mp_subprocess_fd {
int fd; // target FD
// Only one of on_read or src_fd can be set. If none are set, use /dev/null.
// Note: "neutral" initialization requires setting src_fd=-1.
subprocess_read_cb on_read; // if not NULL, serve reads
void *on_read_ctx; // for on_read(on_read_ctx, ...)
subprocess_write_cb on_write; // if not NULL, serve writes
void *on_write_ctx; // for on_write(on_write_ctx, ...)
bstr *write_buf; // must be !=NULL if on_write is set
int src_fd; // if >=0, dup this FD to target FD
};
struct mp_subprocess_opts {
char *exe; // binary to execute (never non-NULL)
char **args; // argument list (NULL for none, otherwise NULL-terminated)
char **env; // if !NULL, set this as environment variable block
// Complete set of FDs passed down. All others are supposed to be closed.
struct mp_subprocess_fd fds[MP_SUBPROCESS_MAX_FDS];
int num_fds;
struct mp_cancel *cancel; // if !NULL, asynchronous process abort (kills it)
bool detach; // if true, do not wait for process to end
};
struct mp_subprocess_result {
int error; // one of MP_SUBPROCESS_* (>0 on error)
// NB: if WIFEXITED applies, error==0, and this is WEXITSTATUS
// on win32, this can use the full 32 bit
// if started with detach==true, this is always 0
uint32_t exit_status; // if error==0==MP_SUBPROCESS_OK, 0 otherwise
};
// Subprocess error values.
#define MP_SUBPROCESS_OK 0 // no error
#define MP_SUBPROCESS_EGENERIC -1 // unknown error
#define MP_SUBPROCESS_EKILLED_BY_US -2 // mp_cancel was triggered
#define MP_SUBPROCESS_EINIT -3 // error during initialization
#define MP_SUBPROCESS_EUNSUPPORTED -4 // API not supported
// Turn MP_SUBPROCESS_* values into a static string. Never returns NULL.
const char *mp_subprocess_err_str(int num);
// Caller must set *opts.
void mp_subprocess2(struct mp_subprocess_opts *opts,
struct mp_subprocess_result *res);
#endif