include/spawn.h

   1 /* Definitions for POSIX spawn interface.
   2    Copyright (C) 2000,2003,2004,2009,2011,2012 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _SPAWN_H
  20 #define _SPAWN_H        1
  21
  22 #include <features.h>
  23 #include <sched.h>
  24 #define __need_sigset_t
  25 #include <signal.h>
  26 #include <sys/types.h>
  27
  28 /* For the tiny inlines (errno/free/memset).  */
  29 #include <errno.h>
  30 #include <string.h>
  31 #include <stdlib.h>
  32
  33
  34 /* Data structure to contain attributes for thread creation.  */
  35 typedef struct
  36 {
  37   short int __flags;
  38   pid_t __pgrp;
  39   sigset_t __sd;
  40   sigset_t __ss;
  41   struct sched_param __sp;
  42   int __policy;
  43   int __pad[16];
  44 } posix_spawnattr_t;
  45
  46
  47 /* Data structure to contain information about the actions to be
  48    performed in the new process with respect to file descriptors.  */
  49 typedef struct
  50 {
  51   int __allocated;
  52   int __used;
  53   struct __spawn_action *__actions;
  54   int __pad[16];
  55 } posix_spawn_file_actions_t;
  56
  57
  58 /* Flags to be set in the `posix_spawnattr_t'.  */
  59 #define POSIX_SPAWN_RESETIDS            0x01
  60 #define POSIX_SPAWN_SETPGROUP           0x02
  61 #define POSIX_SPAWN_SETSIGDEF           0x04
  62 #define POSIX_SPAWN_SETSIGMASK          0x08
  63 #define POSIX_SPAWN_SETSCHEDPARAM       0x10
  64 #define POSIX_SPAWN_SETSCHEDULER        0x20
  65 #ifdef __USE_GNU
  66 # define POSIX_SPAWN_USEVFORK           0x40
  67 #endif
  68
  69 __BEGIN_DECLS
  70
  71 /* Spawn a new process executing PATH with the attributes describes in *ATTRP.
  72    Before running the process perform the actions described in FILE-ACTIONS.
  73
  74    This function is a possible cancellation point and therefore not
  75    marked with __THROW. */
  76 extern int posix_spawn (pid_t *__restrict __pid,
  77                         const char *__restrict __path,
  78                         const posix_spawn_file_actions_t *__restrict
  79                         __file_actions,
  80                         const posix_spawnattr_t *__restrict __attrp,
  81                         char *const __argv[__restrict_arr],
  82                         char *const __envp[__restrict_arr]);
  83
  84 /* Similar to `posix_spawn' but search for FILE in the PATH.
  85
  86    This function is a possible cancellation point and therefore not
  87    marked with __THROW.  */
  88 extern int posix_spawnp (pid_t *__pid, const char *__file,
  89                          const posix_spawn_file_actions_t *__file_actions,
  90                          const posix_spawnattr_t *__attrp,
  91                          char *const __argv[], char *const __envp[]);
  92
  93
  94 /* Initialize data structure with attributes for `spawn' to default values.  */
  95 static inline
  96 int posix_spawnattr_init (posix_spawnattr_t *__attr)
  97 {
  98   memset (__attr, 0, sizeof (*__attr));
  99   return 0;
 100 }
 101
 102 /* Free resources associated with ATTR.  */
 103 static inline
 104 int posix_spawnattr_destroy (posix_spawnattr_t *__attr)
 105 {
 106   return 0;
 107 }
 108
 109 /* Store signal mask for signals with default handling from ATTR in
 110    SIGDEFAULT.  */
 111 static inline
 112 int posix_spawnattr_getsigdefault (const posix_spawnattr_t *
 113                                           __restrict __attr,
 114                                           sigset_t *__restrict __sigdefault)
 115 {
 116   memcpy (__sigdefault, &__attr->__sd, sizeof (sigset_t));
 117   return 0;
 118 }
 119
 120 /* Set signal mask for signals with default handling in ATTR to SIGDEFAULT.  */
 121 static inline
 122 int posix_spawnattr_setsigdefault (posix_spawnattr_t *__restrict __attr,
 123                                           const sigset_t *__restrict
 124                                           __sigdefault)
 125 {
 126   memcpy (&__attr->__sd, __sigdefault, sizeof (sigset_t));
 127   return 0;
 128 }
 129
 130 /* Store signal mask for the new process from ATTR in SIGMASK.  */
 131 static inline
 132 int posix_spawnattr_getsigmask (const posix_spawnattr_t *__restrict
 133                                        __attr,
 134                                        sigset_t *__restrict __sigmask)
 135 {
 136   memcpy (__sigmask, &__attr->__ss, sizeof (sigset_t));
 137   return 0;
 138 }
 139
 140 /* Set signal mask for the new process in ATTR to SIGMASK.  */
 141 static inline
 142 int posix_spawnattr_setsigmask (posix_spawnattr_t *__restrict __attr,
 143                                        const sigset_t *__restrict __sigmask)
 144 {
 145   memcpy (&__attr->__ss, __sigmask, sizeof (sigset_t));
 146   return 0;
 147 }
 148
 149 /* Get flag word from the attribute structure.  */
 150 static inline
 151 int posix_spawnattr_getflags (const posix_spawnattr_t *__restrict
 152                                      __attr,
 153                                      short int *__restrict __flags)
 154 {
 155   *__flags = __attr->__flags;
 156   return 0;
 157 }
 158
 159 /* Store flags in the attribute structure.  */
 160 static inline
 161 int posix_spawnattr_setflags (posix_spawnattr_t *_attr,
 162                                      short int __flags)
 163 {
 164 #ifdef POSIX_SPAWN_USEVFORK
 165 # define __POSIX_SPAWN_USEVFORK POSIX_SPAWN_USEVFORK
 166 #else
 167 # define __POSIX_SPAWN_USEVFORK 0
 168 #endif
 169 #define __POSIX_SPAWN_MASK (POSIX_SPAWN_RESETIDS                \
 170                             | POSIX_SPAWN_SETPGROUP             \
 171                             | POSIX_SPAWN_SETSIGDEF             \
 172                             | POSIX_SPAWN_SETSIGMASK            \
 173                             | POSIX_SPAWN_SETSCHEDPARAM         \
 174                             | POSIX_SPAWN_SETSCHEDULER          \
 175                             | __POSIX_SPAWN_USEVFORK)
 176
 177   /* Check no invalid bits are set.  */
 178   if (__flags & ~__POSIX_SPAWN_MASK)
 179     return EINVAL;
 180
 181   _attr->__flags = __flags;
 182   return 0;
 183 #undef __POSIX_SPAWN_USEVFORK
 184 #undef __POSIX_SPAWN_MASK
 185 }
 186
 187 /* Get process group ID from the attribute structure.  */
 188 static inline
 189 int posix_spawnattr_getpgroup (const posix_spawnattr_t *__restrict
 190                                       __attr, pid_t *__restrict __pgroup)
 191 {
 192   *__pgroup = __attr->__pgrp;
 193   return 0;
 194 }
 195
 196 /* Store process group ID in the attribute structure.  */
 197 static inline
 198 int posix_spawnattr_setpgroup (posix_spawnattr_t *__attr,
 199                                       pid_t __pgroup)
 200 {
 201   __attr->__pgrp = __pgroup;
 202   return 0;
 203 }
 204
 205 /* Get scheduling policy from the attribute structure.  */
 206 static inline
 207 int posix_spawnattr_getschedpolicy (const posix_spawnattr_t *
 208                                            __restrict __attr,
 209                                            int *__restrict __schedpolicy)
 210 {
 211   *__schedpolicy = __attr->__policy;
 212   return 0;
 213 }
 214
 215 /* Store scheduling policy in the attribute structure.  */
 216 static inline
 217 int posix_spawnattr_setschedpolicy (posix_spawnattr_t *__attr,
 218                                            int __schedpolicy)
 219 {
 220   switch (__schedpolicy) {
 221   case SCHED_OTHER:
 222   case SCHED_FIFO:
 223   case SCHED_RR:
 224     break;
 225   default:
 226     return EINVAL;
 227   }
 228
 229   __attr->__policy = __schedpolicy;
 230   return 0;
 231 }
 232
 233 /* Get scheduling parameters from the attribute structure.  */
 234 static inline
 235 int posix_spawnattr_getschedparam (const posix_spawnattr_t *
 236                                           __restrict __attr,
 237                                           struct sched_param *__restrict
 238                                           __schedparam)
 239 {
 240   memcpy (__schedparam, &__attr->__sp, sizeof (__attr->__sp));
 241   return 0;
 242 }
 243
 244 /* Store scheduling parameters in the attribute structure.  */
 245 static inline
 246 int posix_spawnattr_setschedparam (posix_spawnattr_t *__restrict __attr,
 247                                           const struct sched_param *
 248                                           __restrict __schedparam)
 249 {
 250   __attr->__sp = *__schedparam;
 251   return 0;
 252 }
 253
 254 /* Initialize data structure for file attribute for `spawn' call.  */
 255 static inline
 256 int posix_spawn_file_actions_init (posix_spawn_file_actions_t *
 257                                           __file_actions)
 258 {
 259   memset (__file_actions, 0, sizeof (*__file_actions));
 260   return 0;
 261 }
 262
 263 /* Free resources associated with FILE-ACTIONS.  */
 264 static inline
 265 int posix_spawn_file_actions_destroy (posix_spawn_file_actions_t *
 266                                              __file_actions)
 267 {
 268   free (__file_actions->__actions);
 269   return 0;
 270 }
 271
 272 /* Add an action to FILE-ACTIONS which tells the implementation to call
 273    `open' for the given file during the `spawn' call.  */
 274 extern int posix_spawn_file_actions_addopen (posix_spawn_file_actions_t *
 275                                              __restrict __file_actions,
 276                                              int __fd,
 277                                              const char *__restrict __path,
 278                                              int __oflag, mode_t __mode)
 279      __THROW;
 280
 281 /* Add an action to FILE-ACTIONS which tells the implementation to call
 282    `close' for the given file descriptor during the `spawn' call.  */
 283 extern int posix_spawn_file_actions_addclose (posix_spawn_file_actions_t *
 284                                               __file_actions, int __fd)
 285      __THROW;
 286
 287 /* Add an action to FILE-ACTIONS which tells the implementation to call
 288    `dup2' for the given file descriptors during the `spawn' call.  */
 289 extern int posix_spawn_file_actions_adddup2 (posix_spawn_file_actions_t *
 290                                              __file_actions,
 291                                              int __fd, int __newfd) __THROW;
 292
 293 __END_DECLS
 294
 295 #endif /* spawn.h */