| #include "cache.h" |
| #include "run-command.h" |
| #include "exec-cmd.h" |
| #include "sigchain.h" |
| #include "argv-array.h" |
| #include "thread-utils.h" |
| #include "strbuf.h" |
| #include "string-list.h" |
| #include "quote.h" |
| |
| void child_process_init(struct child_process *child) |
| { |
| memset(child, 0, sizeof(*child)); |
| argv_array_init(&child->args); |
| argv_array_init(&child->env_array); |
| } |
| |
| void child_process_clear(struct child_process *child) |
| { |
| argv_array_clear(&child->args); |
| argv_array_clear(&child->env_array); |
| } |
| |
| struct child_to_clean { |
| pid_t pid; |
| struct child_process *process; |
| struct child_to_clean *next; |
| }; |
| static struct child_to_clean *children_to_clean; |
| static int installed_child_cleanup_handler; |
| |
| static void cleanup_children(int sig, int in_signal) |
| { |
| struct child_to_clean *children_to_wait_for = NULL; |
| |
| while (children_to_clean) { |
| struct child_to_clean *p = children_to_clean; |
| children_to_clean = p->next; |
| |
| if (p->process && !in_signal) { |
| struct child_process *process = p->process; |
| if (process->clean_on_exit_handler) { |
| trace_printf( |
| "trace: run_command: running exit handler for pid %" |
| PRIuMAX, (uintmax_t)p->pid |
| ); |
| process->clean_on_exit_handler(process); |
| } |
| } |
| |
| kill(p->pid, sig); |
| |
| if (p->process && p->process->wait_after_clean) { |
| p->next = children_to_wait_for; |
| children_to_wait_for = p; |
| } else { |
| if (!in_signal) |
| free(p); |
| } |
| } |
| |
| while (children_to_wait_for) { |
| struct child_to_clean *p = children_to_wait_for; |
| children_to_wait_for = p->next; |
| |
| while (waitpid(p->pid, NULL, 0) < 0 && errno == EINTR) |
| ; /* spin waiting for process exit or error */ |
| |
| if (!in_signal) |
| free(p); |
| } |
| } |
| |
| static void cleanup_children_on_signal(int sig) |
| { |
| cleanup_children(sig, 1); |
| sigchain_pop(sig); |
| raise(sig); |
| } |
| |
| static void cleanup_children_on_exit(void) |
| { |
| cleanup_children(SIGTERM, 0); |
| } |
| |
| static void mark_child_for_cleanup(pid_t pid, struct child_process *process) |
| { |
| struct child_to_clean *p = xmalloc(sizeof(*p)); |
| p->pid = pid; |
| p->process = process; |
| p->next = children_to_clean; |
| children_to_clean = p; |
| |
| if (!installed_child_cleanup_handler) { |
| atexit(cleanup_children_on_exit); |
| sigchain_push_common(cleanup_children_on_signal); |
| installed_child_cleanup_handler = 1; |
| } |
| } |
| |
| static void clear_child_for_cleanup(pid_t pid) |
| { |
| struct child_to_clean **pp; |
| |
| for (pp = &children_to_clean; *pp; pp = &(*pp)->next) { |
| struct child_to_clean *clean_me = *pp; |
| |
| if (clean_me->pid == pid) { |
| *pp = clean_me->next; |
| free(clean_me); |
| return; |
| } |
| } |
| } |
| |
| static inline void close_pair(int fd[2]) |
| { |
| close(fd[0]); |
| close(fd[1]); |
| } |
| |
| int is_executable(const char *name) |
| { |
| struct stat st; |
| |
| if (stat(name, &st) || /* stat, not lstat */ |
| !S_ISREG(st.st_mode)) |
| return 0; |
| |
| #if defined(GIT_WINDOWS_NATIVE) |
| /* |
| * On Windows there is no executable bit. The file extension |
| * indicates whether it can be run as an executable, and Git |
| * has special-handling to detect scripts and launch them |
| * through the indicated script interpreter. We test for the |
| * file extension first because virus scanners may make |
| * it quite expensive to open many files. |
| */ |
| if (ends_with(name, ".exe")) |
| return S_IXUSR; |
| |
| { |
| /* |
| * Now that we know it does not have an executable extension, |
| * peek into the file instead. |
| */ |
| char buf[3] = { 0 }; |
| int n; |
| int fd = open(name, O_RDONLY); |
| st.st_mode &= ~S_IXUSR; |
| if (fd >= 0) { |
| n = read(fd, buf, 2); |
| if (n == 2) |
| /* look for a she-bang */ |
| if (!strcmp(buf, "#!")) |
| st.st_mode |= S_IXUSR; |
| close(fd); |
| } |
| } |
| #endif |
| return st.st_mode & S_IXUSR; |
| } |
| |
| /* |
| * Search $PATH for a command. This emulates the path search that |
| * execvp would perform, without actually executing the command so it |
| * can be used before fork() to prepare to run a command using |
| * execve() or after execvp() to diagnose why it failed. |
| * |
| * The caller should ensure that file contains no directory |
| * separators. |
| * |
| * Returns the path to the command, as found in $PATH or NULL if the |
| * command could not be found. The caller inherits ownership of the memory |
| * used to store the resultant path. |
| * |
| * This should not be used on Windows, where the $PATH search rules |
| * are more complicated (e.g., a search for "foo" should find |
| * "foo.exe"). |
| */ |
| static char *locate_in_PATH(const char *file) |
| { |
| const char *p = getenv("PATH"); |
| struct strbuf buf = STRBUF_INIT; |
| |
| if (!p || !*p) |
| return NULL; |
| |
| while (1) { |
| const char *end = strchrnul(p, ':'); |
| |
| strbuf_reset(&buf); |
| |
| /* POSIX specifies an empty entry as the current directory. */ |
| if (end != p) { |
| strbuf_add(&buf, p, end - p); |
| strbuf_addch(&buf, '/'); |
| } |
| strbuf_addstr(&buf, file); |
| |
| if (is_executable(buf.buf)) |
| return strbuf_detach(&buf, NULL); |
| |
| if (!*end) |
| break; |
| p = end + 1; |
| } |
| |
| strbuf_release(&buf); |
| return NULL; |
| } |
| |
| static int exists_in_PATH(const char *file) |
| { |
| char *r = locate_in_PATH(file); |
| free(r); |
| return r != NULL; |
| } |
| |
| int sane_execvp(const char *file, char * const argv[]) |
| { |
| if (!execvp(file, argv)) |
| return 0; /* cannot happen ;-) */ |
| |
| /* |
| * When a command can't be found because one of the directories |
| * listed in $PATH is unsearchable, execvp reports EACCES, but |
| * careful usability testing (read: analysis of occasional bug |
| * reports) reveals that "No such file or directory" is more |
| * intuitive. |
| * |
| * We avoid commands with "/", because execvp will not do $PATH |
| * lookups in that case. |
| * |
| * The reassignment of EACCES to errno looks like a no-op below, |
| * but we need to protect against exists_in_PATH overwriting errno. |
| */ |
| if (errno == EACCES && !strchr(file, '/')) |
| errno = exists_in_PATH(file) ? EACCES : ENOENT; |
| else if (errno == ENOTDIR && !strchr(file, '/')) |
| errno = ENOENT; |
| return -1; |
| } |
| |
| static const char **prepare_shell_cmd(struct argv_array *out, const char **argv) |
| { |
| if (!argv[0]) |
| BUG("shell command is empty"); |
| |
| if (strcspn(argv[0], "|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv[0])) { |
| #ifndef GIT_WINDOWS_NATIVE |
| argv_array_push(out, SHELL_PATH); |
| #else |
| argv_array_push(out, "sh"); |
| #endif |
| argv_array_push(out, "-c"); |
| |
| /* |
| * If we have no extra arguments, we do not even need to |
| * bother with the "$@" magic. |
| */ |
| if (!argv[1]) |
| argv_array_push(out, argv[0]); |
| else |
| argv_array_pushf(out, "%s \"$@\"", argv[0]); |
| } |
| |
| argv_array_pushv(out, argv); |
| return out->argv; |
| } |
| |
| #ifndef GIT_WINDOWS_NATIVE |
| static int child_notifier = -1; |
| |
| enum child_errcode { |
| CHILD_ERR_CHDIR, |
| CHILD_ERR_DUP2, |
| CHILD_ERR_CLOSE, |
| CHILD_ERR_SIGPROCMASK, |
| CHILD_ERR_ENOENT, |
| CHILD_ERR_SILENT, |
| CHILD_ERR_ERRNO |
| }; |
| |
| struct child_err { |
| enum child_errcode err; |
| int syserr; /* errno */ |
| }; |
| |
| static void child_die(enum child_errcode err) |
| { |
| struct child_err buf; |
| |
| buf.err = err; |
| buf.syserr = errno; |
| |
| /* write(2) on buf smaller than PIPE_BUF (min 512) is atomic: */ |
| xwrite(child_notifier, &buf, sizeof(buf)); |
| _exit(1); |
| } |
| |
| static void child_dup2(int fd, int to) |
| { |
| if (dup2(fd, to) < 0) |
| child_die(CHILD_ERR_DUP2); |
| } |
| |
| static void child_close(int fd) |
| { |
| if (close(fd)) |
| child_die(CHILD_ERR_CLOSE); |
| } |
| |
| static void child_close_pair(int fd[2]) |
| { |
| child_close(fd[0]); |
| child_close(fd[1]); |
| } |
| |
| /* |
| * parent will make it look like the child spewed a fatal error and died |
| * this is needed to prevent changes to t0061. |
| */ |
| static void fake_fatal(const char *err, va_list params) |
| { |
| vreportf("fatal: ", err, params); |
| } |
| |
| static void child_error_fn(const char *err, va_list params) |
| { |
| const char msg[] = "error() should not be called in child\n"; |
| xwrite(2, msg, sizeof(msg) - 1); |
| } |
| |
| static void child_warn_fn(const char *err, va_list params) |
| { |
| const char msg[] = "warn() should not be called in child\n"; |
| xwrite(2, msg, sizeof(msg) - 1); |
| } |
| |
| static void NORETURN child_die_fn(const char *err, va_list params) |
| { |
| const char msg[] = "die() should not be called in child\n"; |
| xwrite(2, msg, sizeof(msg) - 1); |
| _exit(2); |
| } |
| |
| /* this runs in the parent process */ |
| static void child_err_spew(struct child_process *cmd, struct child_err *cerr) |
| { |
| static void (*old_errfn)(const char *err, va_list params); |
| |
| old_errfn = get_error_routine(); |
| set_error_routine(fake_fatal); |
| errno = cerr->syserr; |
| |
| switch (cerr->err) { |
| case CHILD_ERR_CHDIR: |
| error_errno("exec '%s': cd to '%s' failed", |
| cmd->argv[0], cmd->dir); |
| break; |
| case CHILD_ERR_DUP2: |
| error_errno("dup2() in child failed"); |
| break; |
| case CHILD_ERR_CLOSE: |
| error_errno("close() in child failed"); |
| break; |
| case CHILD_ERR_SIGPROCMASK: |
| error_errno("sigprocmask failed restoring signals"); |
| break; |
| case CHILD_ERR_ENOENT: |
| error_errno("cannot run %s", cmd->argv[0]); |
| break; |
| case CHILD_ERR_SILENT: |
| break; |
| case CHILD_ERR_ERRNO: |
| error_errno("cannot exec '%s'", cmd->argv[0]); |
| break; |
| } |
| set_error_routine(old_errfn); |
| } |
| |
| static void prepare_cmd(struct argv_array *out, const struct child_process *cmd) |
| { |
| if (!cmd->argv[0]) |
| BUG("command is empty"); |
| |
| /* |
| * Add SHELL_PATH so in the event exec fails with ENOEXEC we can |
| * attempt to interpret the command with 'sh'. |
| */ |
| argv_array_push(out, SHELL_PATH); |
| |
| if (cmd->git_cmd) { |
| argv_array_push(out, "git"); |
| argv_array_pushv(out, cmd->argv); |
| } else if (cmd->use_shell) { |
| prepare_shell_cmd(out, cmd->argv); |
| } else { |
| argv_array_pushv(out, cmd->argv); |
| } |
| |
| /* |
| * If there are no '/' characters in the command then perform a path |
| * lookup and use the resolved path as the command to exec. If there |
| * are no '/' characters or if the command wasn't found in the path, |
| * have exec attempt to invoke the command directly. |
| */ |
| if (!strchr(out->argv[1], '/')) { |
| char *program = locate_in_PATH(out->argv[1]); |
| if (program) { |
| free((char *)out->argv[1]); |
| out->argv[1] = program; |
| } |
| } |
| } |
| |
| static char **prep_childenv(const char *const *deltaenv) |
| { |
| extern char **environ; |
| char **childenv; |
| struct string_list env = STRING_LIST_INIT_DUP; |
| struct strbuf key = STRBUF_INIT; |
| const char *const *p; |
| int i; |
| |
| /* Construct a sorted string list consisting of the current environ */ |
| for (p = (const char *const *) environ; p && *p; p++) { |
| const char *equals = strchr(*p, '='); |
| |
| if (equals) { |
| strbuf_reset(&key); |
| strbuf_add(&key, *p, equals - *p); |
| string_list_append(&env, key.buf)->util = (void *) *p; |
| } else { |
| string_list_append(&env, *p)->util = (void *) *p; |
| } |
| } |
| string_list_sort(&env); |
| |
| /* Merge in 'deltaenv' with the current environ */ |
| for (p = deltaenv; p && *p; p++) { |
| const char *equals = strchr(*p, '='); |
| |
| if (equals) { |
| /* ('key=value'), insert or replace entry */ |
| strbuf_reset(&key); |
| strbuf_add(&key, *p, equals - *p); |
| string_list_insert(&env, key.buf)->util = (void *) *p; |
| } else { |
| /* otherwise ('key') remove existing entry */ |
| string_list_remove(&env, *p, 0); |
| } |
| } |
| |
| /* Create an array of 'char *' to be used as the childenv */ |
| ALLOC_ARRAY(childenv, env.nr + 1); |
| for (i = 0; i < env.nr; i++) |
| childenv[i] = env.items[i].util; |
| childenv[env.nr] = NULL; |
| |
| string_list_clear(&env, 0); |
| strbuf_release(&key); |
| return childenv; |
| } |
| |
| struct atfork_state { |
| #ifndef NO_PTHREADS |
| int cs; |
| #endif |
| sigset_t old; |
| }; |
| |
| #define CHECK_BUG(err, msg) \ |
| do { \ |
| int e = (err); \ |
| if (e) \ |
| BUG("%s: %s", msg, strerror(e)); \ |
| } while(0) |
| |
| static void atfork_prepare(struct atfork_state *as) |
| { |
| sigset_t all; |
| |
| if (sigfillset(&all)) |
| die_errno("sigfillset"); |
| #ifdef NO_PTHREADS |
| if (sigprocmask(SIG_SETMASK, &all, &as->old)) |
| die_errno("sigprocmask"); |
| #else |
| CHECK_BUG(pthread_sigmask(SIG_SETMASK, &all, &as->old), |
| "blocking all signals"); |
| CHECK_BUG(pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &as->cs), |
| "disabling cancellation"); |
| #endif |
| } |
| |
| static void atfork_parent(struct atfork_state *as) |
| { |
| #ifdef NO_PTHREADS |
| if (sigprocmask(SIG_SETMASK, &as->old, NULL)) |
| die_errno("sigprocmask"); |
| #else |
| CHECK_BUG(pthread_setcancelstate(as->cs, NULL), |
| "re-enabling cancellation"); |
| CHECK_BUG(pthread_sigmask(SIG_SETMASK, &as->old, NULL), |
| "restoring signal mask"); |
| #endif |
| } |
| #endif /* GIT_WINDOWS_NATIVE */ |
| |
| static inline void set_cloexec(int fd) |
| { |
| int flags = fcntl(fd, F_GETFD); |
| if (flags >= 0) |
| fcntl(fd, F_SETFD, flags | FD_CLOEXEC); |
| } |
| |
| static int wait_or_whine(pid_t pid, const char *argv0, int in_signal) |
| { |
| int status, code = -1; |
| pid_t waiting; |
| int failed_errno = 0; |
| |
| while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR) |
| ; /* nothing */ |
| if (in_signal) |
| return 0; |
| |
| if (waiting < 0) { |
| failed_errno = errno; |
| error_errno("waitpid for %s failed", argv0); |
| } else if (waiting != pid) { |
| error("waitpid is confused (%s)", argv0); |
| } else if (WIFSIGNALED(status)) { |
| code = WTERMSIG(status); |
| if (code != SIGINT && code != SIGQUIT && code != SIGPIPE) |
| error("%s died of signal %d", argv0, code); |
| /* |
| * This return value is chosen so that code & 0xff |
| * mimics the exit code that a POSIX shell would report for |
| * a program that died from this signal. |
| */ |
| code += 128; |
| } else if (WIFEXITED(status)) { |
| code = WEXITSTATUS(status); |
| } else { |
| error("waitpid is confused (%s)", argv0); |
| } |
| |
| clear_child_for_cleanup(pid); |
| |
| errno = failed_errno; |
| return code; |
| } |
| |
| static void trace_add_env(struct strbuf *dst, const char *const *deltaenv) |
| { |
| struct string_list envs = STRING_LIST_INIT_DUP; |
| const char *const *e; |
| int i; |
| int printed_unset = 0; |
| |
| /* Last one wins, see run-command.c:prep_childenv() for context */ |
| for (e = deltaenv; e && *e; e++) { |
| struct strbuf key = STRBUF_INIT; |
| char *equals = strchr(*e, '='); |
| |
| if (equals) { |
| strbuf_add(&key, *e, equals - *e); |
| string_list_insert(&envs, key.buf)->util = equals + 1; |
| } else { |
| string_list_insert(&envs, *e)->util = NULL; |
| } |
| strbuf_release(&key); |
| } |
| |
| /* "unset X Y...;" */ |
| for (i = 0; i < envs.nr; i++) { |
| const char *var = envs.items[i].string; |
| const char *val = envs.items[i].util; |
| |
| if (val || !getenv(var)) |
| continue; |
| |
| if (!printed_unset) { |
| strbuf_addstr(dst, " unset"); |
| printed_unset = 1; |
| } |
| strbuf_addf(dst, " %s", var); |
| } |
| if (printed_unset) |
| strbuf_addch(dst, ';'); |
| |
| /* ... followed by "A=B C=D ..." */ |
| for (i = 0; i < envs.nr; i++) { |
| const char *var = envs.items[i].string; |
| const char *val = envs.items[i].util; |
| const char *oldval; |
| |
| if (!val) |
| continue; |
| |
| oldval = getenv(var); |
| if (oldval && !strcmp(val, oldval)) |
| continue; |
| |
| strbuf_addf(dst, " %s=", var); |
| sq_quote_buf_pretty(dst, val); |
| } |
| string_list_clear(&envs, 0); |
| } |
| |
| static void trace_run_command(const struct child_process *cp) |
| { |
| struct strbuf buf = STRBUF_INIT; |
| |
| if (!trace_want(&trace_default_key)) |
| return; |
| |
| strbuf_addstr(&buf, "trace: run_command:"); |
| if (cp->dir) { |
| strbuf_addstr(&buf, " cd "); |
| sq_quote_buf_pretty(&buf, cp->dir); |
| strbuf_addch(&buf, ';'); |
| } |
| /* |
| * The caller is responsible for initializing cp->env from |
| * cp->env_array if needed. We only check one place. |
| */ |
| if (cp->env) |
| trace_add_env(&buf, cp->env); |
| if (cp->git_cmd) |
| strbuf_addstr(&buf, " git"); |
| sq_quote_argv_pretty(&buf, cp->argv); |
| |
| trace_printf("%s", buf.buf); |
| strbuf_release(&buf); |
| } |
| |
| int start_command(struct child_process *cmd) |
| { |
| int need_in, need_out, need_err; |
| int fdin[2], fdout[2], fderr[2]; |
| int failed_errno; |
| char *str; |
| |
| if (!cmd->argv) |
| cmd->argv = cmd->args.argv; |
| if (!cmd->env) |
| cmd->env = cmd->env_array.argv; |
| |
| /* |
| * In case of errors we must keep the promise to close FDs |
| * that have been passed in via ->in and ->out. |
| */ |
| |
| need_in = !cmd->no_stdin && cmd->in < 0; |
| if (need_in) { |
| if (pipe(fdin) < 0) { |
| failed_errno = errno; |
| if (cmd->out > 0) |
| close(cmd->out); |
| str = "standard input"; |
| goto fail_pipe; |
| } |
| cmd->in = fdin[1]; |
| } |
| |
| need_out = !cmd->no_stdout |
| && !cmd->stdout_to_stderr |
| && cmd->out < 0; |
| if (need_out) { |
| if (pipe(fdout) < 0) { |
| failed_errno = errno; |
| if (need_in) |
| close_pair(fdin); |
| else if (cmd->in) |
| close(cmd->in); |
| str = "standard output"; |
| goto fail_pipe; |
| } |
| cmd->out = fdout[0]; |
| } |
| |
| need_err = !cmd->no_stderr && cmd->err < 0; |
| if (need_err) { |
| if (pipe(fderr) < 0) { |
| failed_errno = errno; |
| if (need_in) |
| close_pair(fdin); |
| else if (cmd->in) |
| close(cmd->in); |
| if (need_out) |
| close_pair(fdout); |
| else if (cmd->out) |
| close(cmd->out); |
| str = "standard error"; |
| fail_pipe: |
| error("cannot create %s pipe for %s: %s", |
| str, cmd->argv[0], strerror(failed_errno)); |
| child_process_clear(cmd); |
| errno = failed_errno; |
| return -1; |
| } |
| cmd->err = fderr[0]; |
| } |
| |
| trace_run_command(cmd); |
| |
| fflush(NULL); |
| |
| #ifndef GIT_WINDOWS_NATIVE |
| { |
| int notify_pipe[2]; |
| int null_fd = -1; |
| char **childenv; |
| struct argv_array argv = ARGV_ARRAY_INIT; |
| struct child_err cerr; |
| struct atfork_state as; |
| |
| if (pipe(notify_pipe)) |
| notify_pipe[0] = notify_pipe[1] = -1; |
| |
| if (cmd->no_stdin || cmd->no_stdout || cmd->no_stderr) { |
| null_fd = open("/dev/null", O_RDWR | O_CLOEXEC); |
| if (null_fd < 0) |
| die_errno(_("open /dev/null failed")); |
| set_cloexec(null_fd); |
| } |
| |
| prepare_cmd(&argv, cmd); |
| childenv = prep_childenv(cmd->env); |
| atfork_prepare(&as); |
| |
| /* |
| * NOTE: In order to prevent deadlocking when using threads special |
| * care should be taken with the function calls made in between the |
| * fork() and exec() calls. No calls should be made to functions which |
| * require acquiring a lock (e.g. malloc) as the lock could have been |
| * held by another thread at the time of forking, causing the lock to |
| * never be released in the child process. This means only |
| * Async-Signal-Safe functions are permitted in the child. |
| */ |
| cmd->pid = fork(); |
| failed_errno = errno; |
| if (!cmd->pid) { |
| int sig; |
| /* |
| * Ensure the default die/error/warn routines do not get |
| * called, they can take stdio locks and malloc. |
| */ |
| set_die_routine(child_die_fn); |
| set_error_routine(child_error_fn); |
| set_warn_routine(child_warn_fn); |
| |
| close(notify_pipe[0]); |
| set_cloexec(notify_pipe[1]); |
| child_notifier = notify_pipe[1]; |
| |
| if (cmd->no_stdin) |
| child_dup2(null_fd, 0); |
| else if (need_in) { |
| child_dup2(fdin[0], 0); |
| child_close_pair(fdin); |
| } else if (cmd->in) { |
| child_dup2(cmd->in, 0); |
| child_close(cmd->in); |
| } |
| |
| if (cmd->no_stderr) |
| child_dup2(null_fd, 2); |
| else if (need_err) { |
| child_dup2(fderr[1], 2); |
| child_close_pair(fderr); |
| } else if (cmd->err > 1) { |
| child_dup2(cmd->err, 2); |
| child_close(cmd->err); |
| } |
| |
| if (cmd->no_stdout) |
| child_dup2(null_fd, 1); |
| else if (cmd->stdout_to_stderr) |
| child_dup2(2, 1); |
| else if (need_out) { |
| child_dup2(fdout[1], 1); |
| child_close_pair(fdout); |
| } else if (cmd->out > 1) { |
| child_dup2(cmd->out, 1); |
| child_close(cmd->out); |
| } |
| |
| if (cmd->dir && chdir(cmd->dir)) |
| child_die(CHILD_ERR_CHDIR); |
| |
| /* |
| * restore default signal handlers here, in case |
| * we catch a signal right before execve below |
| */ |
| for (sig = 1; sig < NSIG; sig++) { |
| /* ignored signals get reset to SIG_DFL on execve */ |
| if (signal(sig, SIG_DFL) == SIG_IGN) |
| signal(sig, SIG_IGN); |
| } |
| |
| if (sigprocmask(SIG_SETMASK, &as.old, NULL) != 0) |
| child_die(CHILD_ERR_SIGPROCMASK); |
| |
| /* |
| * Attempt to exec using the command and arguments starting at |
| * argv.argv[1]. argv.argv[0] contains SHELL_PATH which will |
| * be used in the event exec failed with ENOEXEC at which point |
| * we will try to interpret the command using 'sh'. |
| */ |
| execve(argv.argv[1], (char *const *) argv.argv + 1, |
| (char *const *) childenv); |
| if (errno == ENOEXEC) |
| execve(argv.argv[0], (char *const *) argv.argv, |
| (char *const *) childenv); |
| |
| if (errno == ENOENT) { |
| if (cmd->silent_exec_failure) |
| child_die(CHILD_ERR_SILENT); |
| child_die(CHILD_ERR_ENOENT); |
| } else { |
| child_die(CHILD_ERR_ERRNO); |
| } |
| } |
| atfork_parent(&as); |
| if (cmd->pid < 0) |
| error_errno("cannot fork() for %s", cmd->argv[0]); |
| else if (cmd->clean_on_exit) |
| mark_child_for_cleanup(cmd->pid, cmd); |
| |
| /* |
| * Wait for child's exec. If the exec succeeds (or if fork() |
| * failed), EOF is seen immediately by the parent. Otherwise, the |
| * child process sends a child_err struct. |
| * Note that use of this infrastructure is completely advisory, |
| * therefore, we keep error checks minimal. |
| */ |
| close(notify_pipe[1]); |
| if (xread(notify_pipe[0], &cerr, sizeof(cerr)) == sizeof(cerr)) { |
| /* |
| * At this point we know that fork() succeeded, but exec() |
| * failed. Errors have been reported to our stderr. |
| */ |
| wait_or_whine(cmd->pid, cmd->argv[0], 0); |
| child_err_spew(cmd, &cerr); |
| failed_errno = errno; |
| cmd->pid = -1; |
| } |
| close(notify_pipe[0]); |
| |
| if (null_fd >= 0) |
| close(null_fd); |
| argv_array_clear(&argv); |
| free(childenv); |
| } |
| #else |
| { |
| int fhin = 0, fhout = 1, fherr = 2; |
| const char **sargv = cmd->argv; |
| struct argv_array nargv = ARGV_ARRAY_INIT; |
| |
| if (cmd->no_stdin) |
| fhin = open("/dev/null", O_RDWR); |
| else if (need_in) |
| fhin = dup(fdin[0]); |
| else if (cmd->in) |
| fhin = dup(cmd->in); |
| |
| if (cmd->no_stderr) |
| fherr = open("/dev/null", O_RDWR); |
| else if (need_err) |
| fherr = dup(fderr[1]); |
| else if (cmd->err > 2) |
| fherr = dup(cmd->err); |
| |
| if (cmd->no_stdout) |
| fhout = open("/dev/null", O_RDWR); |
| else if (cmd->stdout_to_stderr) |
| fhout = dup(fherr); |
| else if (need_out) |
| fhout = dup(fdout[1]); |
| else if (cmd->out > 1) |
| fhout = dup(cmd->out); |
| |
| if (cmd->git_cmd) |
| cmd->argv = prepare_git_cmd(&nargv, cmd->argv); |
| else if (cmd->use_shell) |
| cmd->argv = prepare_shell_cmd(&nargv, cmd->argv); |
| |
| cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, (char**) cmd->env, |
| cmd->dir, fhin, fhout, fherr); |
| failed_errno = errno; |
| if (cmd->pid < 0 && (!cmd->silent_exec_failure || errno != ENOENT)) |
| error_errno("cannot spawn %s", cmd->argv[0]); |
| if (cmd->clean_on_exit && cmd->pid >= 0) |
| mark_child_for_cleanup(cmd->pid, cmd); |
| |
| argv_array_clear(&nargv); |
| cmd->argv = sargv; |
| if (fhin != 0) |
| close(fhin); |
| if (fhout != 1) |
| close(fhout); |
| if (fherr != 2) |
| close(fherr); |
| } |
| #endif |
| |
| if (cmd->pid < 0) { |
| if (need_in) |
| close_pair(fdin); |
| else if (cmd->in) |
| close(cmd->in); |
| if (need_out) |
| close_pair(fdout); |
| else if (cmd->out) |
| close(cmd->out); |
| if (need_err) |
| close_pair(fderr); |
| else if (cmd->err) |
| close(cmd->err); |
| child_process_clear(cmd); |
| errno = failed_errno; |
| return -1; |
| } |
| |
| if (need_in) |
| close(fdin[0]); |
| else if (cmd->in) |
| close(cmd->in); |
| |
| if (need_out) |
| close(fdout[1]); |
| else if (cmd->out) |
| close(cmd->out); |
| |
| if (need_err) |
| close(fderr[1]); |
| else if (cmd->err) |
| close(cmd->err); |
| |
| return 0; |
| } |
| |
| int finish_command(struct child_process *cmd) |
| { |
| int ret = wait_or_whine(cmd->pid, cmd->argv[0], 0); |
| child_process_clear(cmd); |
| return ret; |
| } |
| |
| int finish_command_in_signal(struct child_process *cmd) |
| { |
| return wait_or_whine(cmd->pid, cmd->argv[0], 1); |
| } |
| |
| |
| int run_command(struct child_process *cmd) |
| { |
| int code; |
| |
| if (cmd->out < 0 || cmd->err < 0) |
| BUG("run_command with a pipe can cause deadlock"); |
| |
| code = start_command(cmd); |
| if (code) |
| return code; |
| return finish_command(cmd); |
| } |
| |
| int run_command_v_opt(const char **argv, int opt) |
| { |
| return run_command_v_opt_cd_env(argv, opt, NULL, NULL); |
| } |
| |
| int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env) |
| { |
| struct child_process cmd = CHILD_PROCESS_INIT; |
| cmd.argv = argv; |
| cmd.no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0; |
| cmd.git_cmd = opt & RUN_GIT_CMD ? 1 : 0; |
| cmd.stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0; |
| cmd.silent_exec_failure = opt & RUN_SILENT_EXEC_FAILURE ? 1 : 0; |
| cmd.use_shell = opt & RUN_USING_SHELL ? 1 : 0; |
| cmd.clean_on_exit = opt & RUN_CLEAN_ON_EXIT ? 1 : 0; |
| cmd.dir = dir; |
| cmd.env = env; |
| return run_command(&cmd); |
| } |
| |
| #ifndef NO_PTHREADS |
| static pthread_t main_thread; |
| static int main_thread_set; |
| static pthread_key_t async_key; |
| static pthread_key_t async_die_counter; |
| |
| static void *run_thread(void *data) |
| { |
| struct async *async = data; |
| intptr_t ret; |
| |
| if (async->isolate_sigpipe) { |
| sigset_t mask; |
| sigemptyset(&mask); |
| sigaddset(&mask, SIGPIPE); |
| if (pthread_sigmask(SIG_BLOCK, &mask, NULL) < 0) { |
| ret = error("unable to block SIGPIPE in async thread"); |
| return (void *)ret; |
| } |
| } |
| |
| pthread_setspecific(async_key, async); |
| ret = async->proc(async->proc_in, async->proc_out, async->data); |
| return (void *)ret; |
| } |
| |
| static NORETURN void die_async(const char *err, va_list params) |
| { |
| vreportf("fatal: ", err, params); |
| |
| if (in_async()) { |
| struct async *async = pthread_getspecific(async_key); |
| if (async->proc_in >= 0) |
| close(async->proc_in); |
| if (async->proc_out >= 0) |
| close(async->proc_out); |
| pthread_exit((void *)128); |
| } |
| |
| exit(128); |
| } |
| |
| static int async_die_is_recursing(void) |
| { |
| void *ret = pthread_getspecific(async_die_counter); |
| pthread_setspecific(async_die_counter, (void *)1); |
| return ret != NULL; |
| } |
| |
| int in_async(void) |
| { |
| if (!main_thread_set) |
| return 0; /* no asyncs started yet */ |
| return !pthread_equal(main_thread, pthread_self()); |
| } |
| |
| static void NORETURN async_exit(int code) |
| { |
| pthread_exit((void *)(intptr_t)code); |
| } |
| |
| #else |
| |
| static struct { |
| void (**handlers)(void); |
| size_t nr; |
| size_t alloc; |
| } git_atexit_hdlrs; |
| |
| static int git_atexit_installed; |
| |
| static void git_atexit_dispatch(void) |
| { |
| size_t i; |
| |
| for (i=git_atexit_hdlrs.nr ; i ; i--) |
| git_atexit_hdlrs.handlers[i-1](); |
| } |
| |
| static void git_atexit_clear(void) |
| { |
| free(git_atexit_hdlrs.handlers); |
| memset(&git_atexit_hdlrs, 0, sizeof(git_atexit_hdlrs)); |
| git_atexit_installed = 0; |
| } |
| |
| #undef atexit |
| int git_atexit(void (*handler)(void)) |
| { |
| ALLOC_GROW(git_atexit_hdlrs.handlers, git_atexit_hdlrs.nr + 1, git_atexit_hdlrs.alloc); |
| git_atexit_hdlrs.handlers[git_atexit_hdlrs.nr++] = handler; |
| if (!git_atexit_installed) { |
| if (atexit(&git_atexit_dispatch)) |
| return -1; |
| git_atexit_installed = 1; |
| } |
| return 0; |
| } |
| #define atexit git_atexit |
| |
| static int process_is_async; |
| int in_async(void) |
| { |
| return process_is_async; |
| } |
| |
| static void NORETURN async_exit(int code) |
| { |
| exit(code); |
| } |
| |
| #endif |
| |
| void check_pipe(int err) |
| { |
| if (err == EPIPE) { |
| if (in_async()) |
| async_exit(141); |
| |
| signal(SIGPIPE, SIG_DFL); |
| raise(SIGPIPE); |
| /* Should never happen, but just in case... */ |
| exit(141); |
| } |
| } |
| |
| int start_async(struct async *async) |
| { |
| int need_in, need_out; |
| int fdin[2], fdout[2]; |
| int proc_in, proc_out; |
| |
| need_in = async->in < 0; |
| if (need_in) { |
| if (pipe(fdin) < 0) { |
| if (async->out > 0) |
| close(async->out); |
| return error_errno("cannot create pipe"); |
| } |
| async->in = fdin[1]; |
| } |
| |
| need_out = async->out < 0; |
| if (need_out) { |
| if (pipe(fdout) < 0) { |
| if (need_in) |
| close_pair(fdin); |
| else if (async->in) |
| close(async->in); |
| return error_errno("cannot create pipe"); |
| } |
| async->out = fdout[0]; |
| } |
| |
| if (need_in) |
| proc_in = fdin[0]; |
| else if (async->in) |
| proc_in = async->in; |
| else |
| proc_in = -1; |
| |
| if (need_out) |
| proc_out = fdout[1]; |
| else if (async->out) |
| proc_out = async->out; |
| else |
| proc_out = -1; |
| |
| #ifdef NO_PTHREADS |
| /* Flush stdio before fork() to avoid cloning buffers */ |
| fflush(NULL); |
| |
| async->pid = fork(); |
| if (async->pid < 0) { |
| error_errno("fork (async) failed"); |
| goto error; |
| } |
| if (!async->pid) { |
| if (need_in) |
| close(fdin[1]); |
| if (need_out) |
| close(fdout[0]); |
| git_atexit_clear(); |
| process_is_async = 1; |
| exit(!!async->proc(proc_in, proc_out, async->data)); |
| } |
| |
| mark_child_for_cleanup(async->pid, NULL); |
| |
| if (need_in) |
| close(fdin[0]); |
| else if (async->in) |
| close(async->in); |
| |
| if (need_out) |
| close(fdout[1]); |
| else if (async->out) |
| close(async->out); |
| #else |
| if (!main_thread_set) { |
| /* |
| * We assume that the first time that start_async is called |
| * it is from the main thread. |
| */ |
| main_thread_set = 1; |
| main_thread = pthread_self(); |
| pthread_key_create(&async_key, NULL); |
| pthread_key_create(&async_die_counter, NULL); |
| set_die_routine(die_async); |
| set_die_is_recursing_routine(async_die_is_recursing); |
| } |
| |
| if (proc_in >= 0) |
| set_cloexec(proc_in); |
| if (proc_out >= 0) |
| set_cloexec(proc_out); |
| async->proc_in = proc_in; |
| async->proc_out = proc_out; |
| { |
| int err = pthread_create(&async->tid, NULL, run_thread, async); |
| if (err) { |
| error_errno("cannot create thread"); |
| goto error; |
| } |
| } |
| #endif |
| return 0; |
| |
| error: |
| if (need_in) |
| close_pair(fdin); |
| else if (async->in) |
| close(async->in); |
| |
| if (need_out) |
| close_pair(fdout); |
| else if (async->out) |
| close(async->out); |
| return -1; |
| } |
| |
| int finish_async(struct async *async) |
| { |
| #ifdef NO_PTHREADS |
| return wait_or_whine(async->pid, "child process", 0); |
| #else |
| void *ret = (void *)(intptr_t)(-1); |
| |
| if (pthread_join(async->tid, &ret)) |
| error("pthread_join failed"); |
| return (int)(intptr_t)ret; |
| #endif |
| } |
| |
| const char *find_hook(const char *name) |
| { |
| static struct strbuf path = STRBUF_INIT; |
| |
| strbuf_reset(&path); |
| strbuf_git_path(&path, "hooks/%s", name); |
| if (access(path.buf, X_OK) < 0) { |
| int err = errno; |
| |
| #ifdef STRIP_EXTENSION |
| strbuf_addstr(&path, STRIP_EXTENSION); |
| if (access(path.buf, X_OK) >= 0) |
| return path.buf; |
| if (errno == EACCES) |
| err = errno; |
| #endif |
| |
| if (err == EACCES && advice_ignored_hook) { |
| static struct string_list advise_given = STRING_LIST_INIT_DUP; |
| |
| if (!string_list_lookup(&advise_given, name)) { |
| string_list_insert(&advise_given, name); |
| advise(_("The '%s' hook was ignored because " |
| "it's not set as executable.\n" |
| "You can disable this warning with " |
| "`git config advice.ignoredHook false`."), |
| path.buf); |
| } |
| } |
| return NULL; |
| } |
| return path.buf; |
| } |
| |
| int run_hook_ve(const char *const *env, const char *name, va_list args) |
| { |
| struct child_process hook = CHILD_PROCESS_INIT; |
| const char *p; |
| |
| p = find_hook(name); |
| if (!p) |
| return 0; |
| |
| argv_array_push(&hook.args, p); |
| while ((p = va_arg(args, const char *))) |
| argv_array_push(&hook.args, p); |
| hook.env = env; |
| hook.no_stdin = 1; |
| hook.stdout_to_stderr = 1; |
| |
| return run_command(&hook); |
| } |
| |
| int run_hook_le(const char *const *env, const char *name, ...) |
| { |
| va_list args; |
| int ret; |
| |
| va_start(args, name); |
| ret = run_hook_ve(env, name, args); |
| va_end(args); |
| |
| return ret; |
| } |
| |
| struct io_pump { |
| /* initialized by caller */ |
| int fd; |
| int type; /* POLLOUT or POLLIN */ |
| union { |
| struct { |
| const char *buf; |
| size_t len; |
| } out; |
| struct { |
| struct strbuf *buf; |
| size_t hint; |
| } in; |
| } u; |
| |
| /* returned by pump_io */ |
| int error; /* 0 for success, otherwise errno */ |
| |
| /* internal use */ |
| struct pollfd *pfd; |
| }; |
| |
| static int pump_io_round(struct io_pump *slots, int nr, struct pollfd *pfd) |
| { |
| int pollsize = 0; |
| int i; |
| |
| for (i = 0; i < nr; i++) { |
| struct io_pump *io = &slots[i]; |
| if (io->fd < 0) |
| continue; |
| pfd[pollsize].fd = io->fd; |
| pfd[pollsize].events = io->type; |
| io->pfd = &pfd[pollsize++]; |
| } |
| |
| if (!pollsize) |
| return 0; |
| |
| if (poll(pfd, pollsize, -1) < 0) { |
| if (errno == EINTR) |
| return 1; |
| die_errno("poll failed"); |
| } |
| |
| for (i = 0; i < nr; i++) { |
| struct io_pump *io = &slots[i]; |
| |
| if (io->fd < 0) |
| continue; |
| |
| if (!(io->pfd->revents & (POLLOUT|POLLIN|POLLHUP|POLLERR|POLLNVAL))) |
| continue; |
| |
| if (io->type == POLLOUT) { |
| ssize_t len = xwrite(io->fd, |
| io->u.out.buf, io->u.out.len); |
| if (len < 0) { |
| io->error = errno; |
| close(io->fd); |
| io->fd = -1; |
| } else { |
| io->u.out.buf += len; |
| io->u.out.len -= len; |
| if (!io->u.out.len) { |
| close(io->fd); |
| io->fd = -1; |
| } |
| } |
| } |
| |
| if (io->type == POLLIN) { |
| ssize_t len = strbuf_read_once(io->u.in.buf, |
| io->fd, io->u.in.hint); |
| if (len < 0) |
| io->error = errno; |
| if (len <= 0) { |
| close(io->fd); |
| io->fd = -1; |
| } |
| } |
| } |
| |
| return 1; |
| } |
| |
| static int pump_io(struct io_pump *slots, int nr) |
| { |
| struct pollfd *pfd; |
| int i; |
| |
| for (i = 0; i < nr; i++) |
| slots[i].error = 0; |
| |
| ALLOC_ARRAY(pfd, nr); |
| while (pump_io_round(slots, nr, pfd)) |
| ; /* nothing */ |
| free(pfd); |
| |
| /* There may be multiple errno values, so just pick the first. */ |
| for (i = 0; i < nr; i++) { |
| if (slots[i].error) { |
| errno = slots[i].error; |
| return -1; |
| } |
| } |
| return 0; |
| } |
| |
| |
| 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) |
| { |
| struct io_pump io[3]; |
| int nr = 0; |
| |
| if (in) |
| cmd->in = -1; |
| if (out) |
| cmd->out = -1; |
| if (err) |
| cmd->err = -1; |
| |
| if (start_command(cmd) < 0) |
| return -1; |
| |
| if (in) { |
| io[nr].fd = cmd->in; |
| io[nr].type = POLLOUT; |
| io[nr].u.out.buf = in; |
| io[nr].u.out.len = in_len; |
| nr++; |
| } |
| if (out) { |
| io[nr].fd = cmd->out; |
| io[nr].type = POLLIN; |
| io[nr].u.in.buf = out; |
| io[nr].u.in.hint = out_hint; |
| nr++; |
| } |
| if (err) { |
| io[nr].fd = cmd->err; |
| io[nr].type = POLLIN; |
| io[nr].u.in.buf = err; |
| io[nr].u.in.hint = err_hint; |
| nr++; |
| } |
| |
| if (pump_io(io, nr) < 0) { |
| finish_command(cmd); /* throw away exit code */ |
| return -1; |
| } |
| |
| return finish_command(cmd); |
| } |
| |
| enum child_state { |
| GIT_CP_FREE, |
| GIT_CP_WORKING, |
| GIT_CP_WAIT_CLEANUP, |
| }; |
| |
| struct parallel_processes { |
| void *data; |
| |
| int max_processes; |
| int nr_processes; |
| |
| get_next_task_fn get_next_task; |
| start_failure_fn start_failure; |
| task_finished_fn task_finished; |
| |
| struct { |
| enum child_state state; |
| struct child_process process; |
| struct strbuf err; |
| void *data; |
| } *children; |
| /* |
| * The struct pollfd is logically part of *children, |
| * but the system call expects it as its own array. |
| */ |
| struct pollfd *pfd; |
| |
| unsigned shutdown : 1; |
| |
| int output_owner; |
| struct strbuf buffered_output; /* of finished children */ |
| }; |
| |
| static int default_start_failure(struct strbuf *out, |
| void *pp_cb, |
| void *pp_task_cb) |
| { |
| return 0; |
| } |
| |
| static int default_task_finished(int result, |
| struct strbuf *out, |
| void *pp_cb, |
| void *pp_task_cb) |
| { |
| return 0; |
| } |
| |
| static void kill_children(struct parallel_processes *pp, int signo) |
| { |
| int i, n = pp->max_processes; |
| |
| for (i = 0; i < n; i++) |
| if (pp->children[i].state == GIT_CP_WORKING) |
| kill(pp->children[i].process.pid, signo); |
| } |
| |
| static struct parallel_processes *pp_for_signal; |
| |
| static void handle_children_on_signal(int signo) |
| { |
| kill_children(pp_for_signal, signo); |
| sigchain_pop(signo); |
| raise(signo); |
| } |
| |
| static void pp_init(struct parallel_processes *pp, |
| int n, |
| get_next_task_fn get_next_task, |
| start_failure_fn start_failure, |
| task_finished_fn task_finished, |
| void *data) |
| { |
| int i; |
| |
| if (n < 1) |
| n = online_cpus(); |
| |
| pp->max_processes = n; |
| |
| trace_printf("run_processes_parallel: preparing to run up to %d tasks", n); |
| |
| pp->data = data; |
| if (!get_next_task) |
| BUG("you need to specify a get_next_task function"); |
| pp->get_next_task = get_next_task; |
| |
| pp->start_failure = start_failure ? start_failure : default_start_failure; |
| pp->task_finished = task_finished ? task_finished : default_task_finished; |
| |
| pp->nr_processes = 0; |
| pp->output_owner = 0; |
| pp->shutdown = 0; |
| pp->children = xcalloc(n, sizeof(*pp->children)); |
| pp->pfd = xcalloc(n, sizeof(*pp->pfd)); |
| strbuf_init(&pp->buffered_output, 0); |
| |
| for (i = 0; i < n; i++) { |
| strbuf_init(&pp->children[i].err, 0); |
| child_process_init(&pp->children[i].process); |
| pp->pfd[i].events = POLLIN | POLLHUP; |
| pp->pfd[i].fd = -1; |
| } |
| |
| pp_for_signal = pp; |
| sigchain_push_common(handle_children_on_signal); |
| } |
| |
| static void pp_cleanup(struct parallel_processes *pp) |
| { |
| int i; |
| |
| trace_printf("run_processes_parallel: done"); |
| for (i = 0; i < pp->max_processes; i++) { |
| strbuf_release(&pp->children[i].err); |
| child_process_clear(&pp->children[i].process); |
| } |
| |
| free(pp->children); |
| free(pp->pfd); |
| |
| /* |
| * When get_next_task added messages to the buffer in its last |
| * iteration, the buffered output is non empty. |
| */ |
| strbuf_write(&pp->buffered_output, stderr); |
| strbuf_release(&pp->buffered_output); |
| |
| sigchain_pop_common(); |
| } |
| |
| /* returns |
| * 0 if a new task was started. |
| * 1 if no new jobs was started (get_next_task ran out of work, non critical |
| * problem with starting a new command) |
| * <0 no new job was started, user wishes to shutdown early. Use negative code |
| * to signal the children. |
| */ |
| static int pp_start_one(struct parallel_processes *pp) |
| { |
| int i, code; |
| |
| for (i = 0; i < pp->max_processes; i++) |
| if (pp->children[i].state == GIT_CP_FREE) |
| break; |
| if (i == pp->max_processes) |
| BUG("bookkeeping is hard"); |
| |
| code = pp->get_next_task(&pp->children[i].process, |
| &pp->children[i].err, |
| pp->data, |
| &pp->children[i].data); |
| if (!code) { |
| strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); |
| strbuf_reset(&pp->children[i].err); |
| return 1; |
| } |
| pp->children[i].process.err = -1; |
| pp->children[i].process.stdout_to_stderr = 1; |
| pp->children[i].process.no_stdin = 1; |
| |
| if (start_command(&pp->children[i].process)) { |
| code = pp->start_failure(&pp->children[i].err, |
| pp->data, |
| pp->children[i].data); |
| strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); |
| strbuf_reset(&pp->children[i].err); |
| if (code) |
| pp->shutdown = 1; |
| return code; |
| } |
| |
| pp->nr_processes++; |
| pp->children[i].state = GIT_CP_WORKING; |
| pp->pfd[i].fd = pp->children[i].process.err; |
| return 0; |
| } |
| |
| static void pp_buffer_stderr(struct parallel_processes *pp, int output_timeout) |
| { |
| int i; |
| |
| while ((i = poll(pp->pfd, pp->max_processes, output_timeout)) < 0) { |
| if (errno == EINTR) |
| continue; |
| pp_cleanup(pp); |
| die_errno("poll"); |
| } |
| |
| /* Buffer output from all pipes. */ |
| for (i = 0; i < pp->max_processes; i++) { |
| if (pp->children[i].state == GIT_CP_WORKING && |
| pp->pfd[i].revents & (POLLIN | POLLHUP)) { |
| int n = strbuf_read_once(&pp->children[i].err, |
| pp->children[i].process.err, 0); |
| if (n == 0) { |
| close(pp->children[i].process.err); |
| pp->children[i].state = GIT_CP_WAIT_CLEANUP; |
| } else if (n < 0) |
| if (errno != EAGAIN) |
| die_errno("read"); |
| } |
| } |
| } |
| |
| static void pp_output(struct parallel_processes *pp) |
| { |
| int i = pp->output_owner; |
| if (pp->children[i].state == GIT_CP_WORKING && |
| pp->children[i].err.len) { |
| strbuf_write(&pp->children[i].err, stderr); |
| strbuf_reset(&pp->children[i].err); |
| } |
| } |
| |
| static int pp_collect_finished(struct parallel_processes *pp) |
| { |
| int i, code; |
| int n = pp->max_processes; |
| int result = 0; |
| |
| while (pp->nr_processes > 0) { |
| for (i = 0; i < pp->max_processes; i++) |
| if (pp->children[i].state == GIT_CP_WAIT_CLEANUP) |
| break; |
| if (i == pp->max_processes) |
| break; |
| |
| code = finish_command(&pp->children[i].process); |
| |
| code = pp->task_finished(code, |
| &pp->children[i].err, pp->data, |
| pp->children[i].data); |
| |
| if (code) |
| result = code; |
| if (code < 0) |
| break; |
| |
| pp->nr_processes--; |
| pp->children[i].state = GIT_CP_FREE; |
| pp->pfd[i].fd = -1; |
| child_process_init(&pp->children[i].process); |
| |
| if (i != pp->output_owner) { |
| strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); |
| strbuf_reset(&pp->children[i].err); |
| } else { |
| strbuf_write(&pp->children[i].err, stderr); |
| strbuf_reset(&pp->children[i].err); |
| |
| /* Output all other finished child processes */ |
| strbuf_write(&pp->buffered_output, stderr); |
| strbuf_reset(&pp->buffered_output); |
| |
| /* |
| * Pick next process to output live. |
| * NEEDSWORK: |
| * For now we pick it randomly by doing a round |
| * robin. Later we may want to pick the one with |
| * the most output or the longest or shortest |
| * running process time. |
| */ |
| for (i = 0; i < n; i++) |
| if (pp->children[(pp->output_owner + i) % n].state == GIT_CP_WORKING) |
| break; |
| pp->output_owner = (pp->output_owner + i) % n; |
| } |
| } |
| return result; |
| } |
| |
| int run_processes_parallel(int n, |
| get_next_task_fn get_next_task, |
| start_failure_fn start_failure, |
| task_finished_fn task_finished, |
| void *pp_cb) |
| { |
| int i, code; |
| int output_timeout = 100; |
| int spawn_cap = 4; |
| struct parallel_processes pp; |
| |
| pp_init(&pp, n, get_next_task, start_failure, task_finished, pp_cb); |
| while (1) { |
| for (i = 0; |
| i < spawn_cap && !pp.shutdown && |
| pp.nr_processes < pp.max_processes; |
| i++) { |
| code = pp_start_one(&pp); |
| if (!code) |
| continue; |
| if (code < 0) { |
| pp.shutdown = 1; |
| kill_children(&pp, -code); |
| } |
| break; |
| } |
| if (!pp.nr_processes) |
| break; |
| pp_buffer_stderr(&pp, output_timeout); |
| pp_output(&pp); |
| code = pp_collect_finished(&pp); |
| if (code) { |
| pp.shutdown = 1; |
| if (code < 0) |
| kill_children(&pp, -code); |
| } |
| } |
| |
| pp_cleanup(&pp); |
| return 0; |
| } |