From 3c1842a44c305fc36a39fec10fab78ad2db84f9e Mon Sep 17 00:00:00 2001 From: davidxu Date: Tue, 17 Jun 2008 06:26:29 +0000 Subject: Add POSIX routines called posix_spawn() and posix_spawnp(), which can be used as replacements for exec/fork in a lot of cases. This change also added execvpe() which allows environment variable PATH to be used for searching executable file, it is used for implementing posix_spawnp(). PR: standards/122051 --- lib/libc/gen/Makefile.inc | 4 +- lib/libc/gen/Symbol.map | 22 +++ lib/libc/gen/exec.3 | 17 +- lib/libc/gen/exec.c | 31 ++- lib/libc/gen/posix_spawn.c | 472 +++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 532 insertions(+), 14 deletions(-) create mode 100644 lib/libc/gen/posix_spawn.c (limited to 'lib/libc') diff --git a/lib/libc/gen/Makefile.inc b/lib/libc/gen/Makefile.inc index c39fdb3..30a8b8f 100644 --- a/lib/libc/gen/Makefile.inc +++ b/lib/libc/gen/Makefile.inc @@ -21,7 +21,7 @@ SRCS+= __getosreldate.c __xuname.c \ initgroups.c isatty.c isinf.c isnan.c jrand48.c lcong48.c \ lockf.c lrand48.c mrand48.c nftw.c nice.c \ nlist.c nrand48.c opendir.c \ - pause.c pmadvise.c popen.c pselect.c \ + pause.c pmadvise.c popen.c posix_spawn.c pselect.c \ psignal.c pw_scan.c pwcache.c \ raise.c readdir.c readpassphrase.c rewinddir.c \ scandir.c seed48.c seekdir.c sem.c semctl.c \ @@ -81,7 +81,7 @@ MLINKS+=err.3 err_set_exit.3 err.3 err_set_file.3 err.3 errc.3 err.3 errx.3 \ err.3 verr.3 err.3 verrc.3 err.3 verrx.3 err.3 vwarn.3 err.3 vwarnc.3 \ err.3 vwarnx.3 err.3 warnc.3 err.3 warn.3 err.3 warnx.3 MLINKS+=exec.3 execl.3 exec.3 execle.3 exec.3 execlp.3 exec.3 exect.3 \ - exec.3 execv.3 exec.3 execvp.3 exec.3 execvP.3 + exec.3 execv.3 exec.3 execvP.3 exec.3 execvp.3 exec.3 execvpe.3 MLINKS+=fpclassify.3 finite.3 fpclassify.3 finitef.3 \ fpclassify.3 isfinite.3 fpclassify.3 isinf.3 fpclassify.3 isnan.3 \ fpclassify.3 isnormal.3 diff --git a/lib/libc/gen/Symbol.map b/lib/libc/gen/Symbol.map index 22c4395..4970bcb 100644 --- a/lib/libc/gen/Symbol.map +++ b/lib/libc/gen/Symbol.map @@ -329,6 +329,7 @@ FBSD_1.0 { }; FBSD_1.1 { + execvpe; fdopendir; fts_open; fts_close; @@ -339,6 +340,27 @@ FBSD_1.1 { fts_get_stream; fts_set_clientptr; tcgetsid; + posix_spawn; + posix_spawn_file_actions_addclose; + posix_spawn_file_actions_adddup2; + posix_spawn_file_actions_addopen; + posix_spawn_file_actions_destroy; + posix_spawn_file_actions_init; + posix_spawnattr_destroy; + posix_spawnattr_getflags; + posix_spawnattr_getpgroup; + posix_spawnattr_getschedparam; + posix_spawnattr_getschedpolicy; + posix_spawnattr_getsigdefault; + posix_spawnattr_getsigmask; + posix_spawnattr_init; + posix_spawnattr_setflags; + posix_spawnattr_setpgroup; + posix_spawnattr_setschedparam; + posix_spawnattr_setschedpolicy; + posix_spawnattr_setsigdefault; + posix_spawnattr_setsigmask; + posix_spawnp; }; FBSDprivate_1.0 { diff --git a/lib/libc/gen/exec.3 b/lib/libc/gen/exec.3 index daeccd1..448a1b9 100644 --- a/lib/libc/gen/exec.3 +++ b/lib/libc/gen/exec.3 @@ -38,6 +38,7 @@ .Nm exect , .Nm execv , .Nm execvp , +.Nm execvpe , .Nm execvP .Nd execute a file .Sh LIBRARY @@ -64,6 +65,8 @@ .Ft int .Fn execvp "const char *file" "char *const argv[]" .Ft int +.Fn execvpe "const char *file" "char *const argv[]" "char *const envp[]" +.Ft int .Fn execvP "const char *file" "const char *search_path" "char *const argv[]" .Sh DESCRIPTION The @@ -118,9 +121,10 @@ be terminated by a pointer. .Pp The -.Fn execle -and +.Fn execle , .Fn exect +and +.Fn execvpe functions also specify the environment of the executed process by following the .Dv NULL @@ -142,6 +146,7 @@ Some of these functions have special semantics. The functions .Fn execlp , .Fn execvp , +.Fn execvpe , and .Fn execvP will duplicate the actions of the shell in searching for an executable file @@ -152,6 +157,7 @@ For .Fn execlp and .Fn execvp , +.Fn execvpe , search path is the path specified in the environment by .Dq Ev PATH variable. @@ -277,7 +283,8 @@ The .Fn execl , .Fn execle , .Fn execlp , -.Fn execvp +.Fn execvp , +.Fn execvpe and .Fn execvP functions @@ -319,3 +326,7 @@ The .Fn execvP function first appeared in .Fx 5.2 . +The +.Fn execvpe +function first appeared in +.Fx 8.0 . diff --git a/lib/libc/gen/exec.c b/lib/libc/gen/exec.c index 2cf7a36..4525ce2 100644 --- a/lib/libc/gen/exec.c +++ b/lib/libc/gen/exec.c @@ -140,20 +140,15 @@ execv(name, argv) int execvp(const char *name, char * const *argv) { - const char *path; - - /* Get the path we're searching. */ - if ((path = getenv("PATH")) == NULL) - path = _PATH_DEFPATH; - - return (execvP(name, path, argv)); + return (execvpe(name, argv, environ)); } -int -execvP(name, path, argv) +static int +execvPe(name, path, argv, envp) const char *name; const char *path; char * const *argv; + char * const *envp; { char **memp; int cnt, lp, ln; @@ -269,3 +264,21 @@ retry: (void)_execve(bp, argv, environ); done: return (-1); } + +int +execvP(const char *name, const char *path, char * const argv[]) +{ + return execvPe(name, path, argv, environ); +} + +int +execvpe(const char *name, char * const argv[], char * const envp[]) +{ + const char *path; + + /* Get the path we're searching. */ + if ((path = getenv("PATH")) == NULL) + path = _PATH_DEFPATH; + + return (execvPe(name, path, argv, envp)); +} diff --git a/lib/libc/gen/posix_spawn.c b/lib/libc/gen/posix_spawn.c new file mode 100644 index 0000000..bc135ff --- /dev/null +++ b/lib/libc/gen/posix_spawn.c @@ -0,0 +1,472 @@ +/*- + * Copyright (c) 2008 Ed Schouten + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include +__FBSDID("$FreeBSD$"); + +#include "namespace.h" +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include "un-namespace.h" + +extern char **environ; + +struct __posix_spawnattr { + short sa_flags; + pid_t sa_pgroup; + struct sched_param sa_schedparam; + int sa_schedpolicy; + sigset_t sa_sigdefault; + sigset_t sa_sigmask; +}; + +struct __posix_spawn_file_actions { + STAILQ_HEAD(, __posix_spawn_file_actions_entry) fa_list; +}; + +typedef struct __posix_spawn_file_actions_entry { + STAILQ_ENTRY(__posix_spawn_file_actions_entry) fae_list; + enum { FAE_OPEN, FAE_DUP2, FAE_CLOSE } fae_action; + + int fae_fildes; + union { + struct { + char *path; +#define fae_path fae_data.open.path + int oflag; +#define fae_oflag fae_data.open.oflag + mode_t mode; +#define fae_mode fae_data.open.mode + } open; + struct { + int newfildes; +#define fae_newfildes fae_data.dup2.newfildes + } dup2; + } fae_data; +} posix_spawn_file_actions_entry_t; + +/* + * Spawn routines + */ + +static int +process_spawnattr(const posix_spawnattr_t sa) +{ + struct sigaction sigact = { .sa_flags = 0, .sa_handler = SIG_DFL }; + int i; + + /* + * POSIX doesn't really describe in which order everything + * should be set. We'll just set them in the order in which they + * are mentioned. + */ + + /* Set signal masks/defaults */ + if (sa->sa_flags & POSIX_SPAWN_SETSIGMASK) { + _sigprocmask(SIG_SETMASK, &sa->sa_sigmask, NULL); + } + + if (sa->sa_flags & POSIX_SPAWN_SETSIGDEF) { + for (i = 1; i <= _SIG_MAXSIG; i++) { + if (sigismember(&sa->sa_sigdefault, i)) + if (_sigaction(i, &sigact, NULL) != 0) + return (errno); + } + } + + /* Reset user ID's */ + if (sa->sa_flags & POSIX_SPAWN_RESETIDS) { + if (setegid(getgid()) != 0) + return (errno); + if (seteuid(getuid()) != 0) + return (errno); + } + + /* Set process group */ + if (sa->sa_flags & POSIX_SPAWN_SETPGROUP) { + if (setpgid(0, sa->sa_pgroup) != 0) + return (errno); + } + + /* Set scheduler policy */ + if (sa->sa_flags & POSIX_SPAWN_SETSCHEDULER) { + if (sched_setscheduler(0, sa->sa_schedpolicy, + &sa->sa_schedparam) != 0) + return (errno); + } else if (sa->sa_flags & POSIX_SPAWN_SETSCHEDPARAM) { + if (sched_setparam(0, &sa->sa_schedparam) != 0) + return (errno); + } + return (0); +} + +static int +process_file_actions_entry(posix_spawn_file_actions_entry_t *fae) +{ + int fd; + + switch (fae->fae_action) { + case FAE_OPEN: + /* Perform an open(), make it use the right fd */ + fd = _open(fae->fae_path, fae->fae_oflag, fae->fae_mode); + if (fd < 0) + return (errno); + if (fd != fae->fae_fildes) { + if (_dup2(fd, fae->fae_fildes) == -1) + return (errno); + if (_close(fd) != 0) { + if (errno == EBADF) + return (EBADF); + } + } + if (_fcntl(fae->fae_fildes, F_SETFD, 0) == -1) + return (errno); + break; + case FAE_DUP2: + /* Perform a dup2() */ + if (_dup2(fae->fae_fildes, fae->fae_newfildes) == -1) + return (errno); + if (_fcntl(fae->fae_newfildes, F_SETFD, 0) == -1) + return (errno); + break; + case FAE_CLOSE: + /* Perform a close() */ + if (_close(fae->fae_fildes) != 0) { + if (errno == EBADF) + return (EBADF); + } + break; + } + return (0); +} + +static int +process_file_actions(const posix_spawn_file_actions_t fa) +{ + posix_spawn_file_actions_entry_t *fae; + int error; + + /* Replay all file descriptor modifications */ + STAILQ_FOREACH(fae, &fa->fa_list, fae_list) { + error = process_file_actions_entry(fae); + if (error) + return (error); + } + return (0); +} + +static int +do_posix_spawn(pid_t *pid, const char *path, + const posix_spawn_file_actions_t *fa, + const posix_spawnattr_t *sa, + char * const argv[], char * const envp[], int use_env_path) +{ + pid_t p; + volatile int error = 0; + + p = vfork(); + switch (p) { + case -1: + return (errno); + case 0: + if (sa != NULL) { + error = process_spawnattr(*sa); + if (error) + _exit(127); + } + if (fa != NULL) { + error = process_file_actions(*fa); + if (error) + _exit(127); + } + if (use_env_path) + execvpe(path, argv, envp != NULL ? envp : environ); + else + _execve(path, argv, envp != NULL ? envp : environ); + error = errno; + _exit(127); + default: + if (pid != NULL) + *pid = p; + return (error); + } +} + +int +posix_spawn(pid_t *pid, const char *path, + const posix_spawn_file_actions_t *fa, + const posix_spawnattr_t *sa, + char * const argv[], char * const envp[]) +{ + return do_posix_spawn(pid, path, fa, sa, argv, envp, 0); +} + +int +posix_spawnp(pid_t *pid, const char *path, + const posix_spawn_file_actions_t *fa, + const posix_spawnattr_t *sa, + char * const argv[], char * const envp[]) +{ + return do_posix_spawn(pid, path, fa, sa, argv, envp, 1); +} + +/* + * File descriptor actions + */ + +int +posix_spawn_file_actions_init(posix_spawn_file_actions_t *ret) +{ + posix_spawn_file_actions_t fa; + + fa = malloc(sizeof(struct __posix_spawn_file_actions)); + if (fa == NULL) + return (-1); + + STAILQ_INIT(&fa->fa_list); + *ret = fa; + return (0); +} + +int +posix_spawn_file_actions_destroy(posix_spawn_file_actions_t *fa) +{ + posix_spawn_file_actions_entry_t *fae; + + while ((fae = STAILQ_FIRST(&(*fa)->fa_list)) != NULL) { + /* Remove file action entry from the queue */ + STAILQ_REMOVE_HEAD(&(*fa)->fa_list, fae_list); + + /* Deallocate file action entry */ + if (fae->fae_action == FAE_OPEN) + free(fae->fae_path); + free(fae); + } + + free(*fa); + return (0); +} + +int +posix_spawn_file_actions_addopen(posix_spawn_file_actions_t * __restrict fa, + int fildes, const char * __restrict path, int oflag, mode_t mode) +{ + posix_spawn_file_actions_entry_t *fae; + int error; + + if (fildes < 0) + return (EBADF); + + /* Allocate object */ + fae = malloc(sizeof(posix_spawn_file_actions_entry_t)); + if (fae == NULL) + return (errno); + + /* Set values and store in queue */ + fae->fae_action = FAE_OPEN; + fae->fae_path = strdup(path); + if (fae->fae_path == NULL) { + error = errno; + free(fae); + return (error); + } + fae->fae_fildes = fildes; + fae->fae_oflag = oflag; + fae->fae_mode = mode; + + STAILQ_INSERT_TAIL(&(*fa)->fa_list, fae, fae_list); + return (0); +} + +int +posix_spawn_file_actions_adddup2(posix_spawn_file_actions_t *fa, + int fildes, int newfildes) +{ + posix_spawn_file_actions_entry_t *fae; + + if (fildes < 0 || newfildes < 0) + return (EBADF); + + /* Allocate object */ + fae = malloc(sizeof(posix_spawn_file_actions_entry_t)); + if (fae == NULL) + return (errno); + + /* Set values and store in queue */ + fae->fae_action = FAE_DUP2; + fae->fae_fildes = fildes; + fae->fae_newfildes = newfildes; + + STAILQ_INSERT_TAIL(&(*fa)->fa_list, fae, fae_list); + return (0); +} + +int posix_spawn_file_actions_addclose(posix_spawn_file_actions_t *fa, + int fildes) +{ + posix_spawn_file_actions_entry_t *fae; + + if (fildes < 0) + return (EBADF); + + /* Allocate object */ + fae = malloc(sizeof(posix_spawn_file_actions_entry_t)); + if (fae == NULL) + return (errno); + + /* Set values and store in queue */ + fae->fae_action = FAE_CLOSE; + fae->fae_fildes = fildes; + + STAILQ_INSERT_TAIL(&(*fa)->fa_list, fae, fae_list); + return (0); +} + +/* + * Spawn attributes + */ + +int +posix_spawnattr_init(posix_spawnattr_t *ret) +{ + posix_spawnattr_t sa; + + sa = calloc(1, sizeof(struct __posix_spawnattr)); + if (sa == NULL) + return (errno); + + /* Set defaults as specified by POSIX, cleared above */ + *ret = sa; + return (0); +} + +int +posix_spawnattr_destroy(posix_spawnattr_t *sa) +{ + free(*sa); + return (0); +} + +int +posix_spawnattr_getflags(const posix_spawnattr_t * __restrict sa, + short * __restrict flags) +{ + *flags = (*sa)->sa_flags; + return (0); +} + +int +posix_spawnattr_getpgroup(const posix_spawnattr_t * __restrict sa, + pid_t * __restrict pgroup) +{ + *pgroup = (*sa)->sa_pgroup; + return (0); +} + +int +posix_spawnattr_getschedparam(const posix_spawnattr_t * __restrict sa, + struct sched_param * __restrict schedparam) +{ + *schedparam = (*sa)->sa_schedparam; + return (0); +} + +int +posix_spawnattr_getschedpolicy(const posix_spawnattr_t * __restrict sa, + int * __restrict schedpolicy) +{ + *schedpolicy = (*sa)->sa_schedpolicy; + return (0); +} + +int +posix_spawnattr_getsigdefault(const posix_spawnattr_t * __restrict sa, + sigset_t * __restrict sigdefault) +{ + *sigdefault = (*sa)->sa_sigdefault; + return (0); +} + +int +posix_spawnattr_getsigmask(const posix_spawnattr_t * __restrict sa, + sigset_t * __restrict sigmask) +{ + *sigmask = (*sa)->sa_sigmask; + return (0); +} + +int +posix_spawnattr_setflags(posix_spawnattr_t *sa, short flags) +{ + (*sa)->sa_flags = flags; + return (0); +} + +int +posix_spawnattr_setpgroup(posix_spawnattr_t *sa, pid_t pgroup) +{ + (*sa)->sa_pgroup = pgroup; + return (0); +} + +int +posix_spawnattr_setschedparam(posix_spawnattr_t *sa __restrict, + const struct sched_param * __restrict schedparam) +{ + (*sa)->sa_schedparam = *schedparam; + return (0); +} + +int +posix_spawnattr_setschedpolicy(posix_spawnattr_t *sa, int schedpolicy) +{ + (*sa)->sa_schedpolicy = schedpolicy; + return (0); +} + +int +posix_spawnattr_setsigdefault(posix_spawnattr_t * __restrict sa, + const sigset_t * __restrict sigdefault) +{ + (*sa)->sa_sigdefault = *sigdefault; + return (0); +} + +int +posix_spawnattr_setsigmask(posix_spawnattr_t * __restrict sa, + const sigset_t * __restrict sigmask) +{ + (*sa)->sa_sigmask = *sigmask; + return (0); +} -- cgit v1.1