9658846ce3
When write_or_die() sees EPIPE, it treats it specially by converting it into a SIGPIPE death. We obviously cannot ignore it, as the write has failed and the caller expects us to die. But likewise, we cannot just call die(), because printing any message at all would be a nuisance during normal operations. However, this is a problem if write_or_die() is called from a thread. Our raised signal ends up killing the whole process, when logically we just need to kill the thread (after all, if we are ignoring SIGPIPE, there is good reason to think that the main thread is expecting to handle it). Inside an async thread, the die() code already does the right thing, because we use our custom die_async() routine, which calls pthread_join(). So ideally we would piggy-back on that, and simply call: die_quietly_with_code(141); or similar. But refactoring the die code to do this is surprisingly non-trivial. The die_routines themselves handle both printing and the decision of the exit code. Every one of them would have to be modified to take new parameters for the code, and to tell us to be quiet. Instead, we can just teach write_or_die() to check for the async case and handle it specially. We do have to build an interface to abstract the async exit, but it's simple and self-contained. If we had many call-sites that wanted to do this die_quietly_with_code(), this approach wouldn't scale as well, but we don't. This is the only place where do this weird exit trick. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
127 lines
4.1 KiB
C
127 lines
4.1 KiB
C
#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);
|
|
|
|
#endif
|