linux/tools/lib/subcmd/run-command.h
Ian Rogers 1a562c0d44 tools subcmd: Add a no exec function call option
Tools like perf fork tests in case they crash, but they don't want to
exec a full binary. Add an option to call a function rather than do an
exec. The child process exits with the result of the function call and
is passed the struct of the run_command, things like container_of can
then allow the child process function to determine additional
arguments.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: James Clark <james.clark@arm.com>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Bill Wendling <morbo@google.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: llvm@lists.linux.dev
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240221034155.1500118-5-irogers@google.com
2024-02-22 09:12:25 -08:00

64 lines
2.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __SUBCMD_RUN_COMMAND_H
#define __SUBCMD_RUN_COMMAND_H
#include <unistd.h>
enum {
ERR_RUN_COMMAND_FORK = 10000,
ERR_RUN_COMMAND_EXEC,
ERR_RUN_COMMAND_PIPE,
ERR_RUN_COMMAND_WAITPID,
ERR_RUN_COMMAND_WAITPID_WRONG_PID,
ERR_RUN_COMMAND_WAITPID_SIGNAL,
ERR_RUN_COMMAND_WAITPID_NOEXIT,
};
#define IS_RUN_COMMAND_ERR(x) (-(x) >= ERR_RUN_COMMAND_FORK)
struct child_process {
const char **argv;
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 > 0 not supported
* 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 exec_cmd:1; /* if this is to be external sub-command */
unsigned stdout_to_stderr:1;
void (*preexec_cb)(void);
/* If set, call function in child rather than doing an exec. */
int (*no_exec_cmd)(struct child_process *process);
};
int start_command(struct child_process *);
int finish_command(struct child_process *);
int run_command(struct child_process *);
#define RUN_COMMAND_NO_STDIN 1
#define RUN_EXEC_CMD 2 /*If this is to be external sub-command */
#define RUN_COMMAND_STDOUT_TO_STDERR 4
int run_command_v_opt(const char **argv, int opt);
#endif /* __SUBCMD_RUN_COMMAND_H */