1 /* Guts of POSIX spawn interface. Generic POSIX.1 version.
2 Copyright (C) 2000,01,02 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
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.
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.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
27 #include "spawn_int.h"
30 /* The Unix standard contains a long explanation of the way to signal
31 an error after the fork() was successful. Since no new wait status
32 was wanted there is no way to signal an error using one of the
33 available methods. The committee chose to signal an error by a
34 normal program exit with the exit code 127. */
35 #define SPAWN_ERROR 127
38 /* The file is accessible but it is not an executable file. Invoke
39 the shell to interpret it as a script. */
42 script_execute (const char *file
, char *const argv
[], char *const envp
[])
44 /* Count the arguments. */
49 /* Construct an argument list for the shell. */
51 char *new_argv
[argc
+ 1];
52 new_argv
[0] = (char *) _PATH_BSHELL
;
53 new_argv
[1] = (char *) file
;
56 new_argv
[argc
] = argv
[argc
- 1];
60 /* Execute the shell. */
61 __execve (new_argv
[0], new_argv
, envp
);
66 /* Spawn a new process executing PATH with the attributes describes in *ATTRP.
67 Before running the process perform the actions described in FILE-ACTIONS. */
69 __spawni (pid_t
*pid
, const char *file
,
70 const posix_spawn_file_actions_t
*file_actions
,
71 const posix_spawnattr_t
*attrp
, char *const argv
[],
72 char *const envp
[], int use_path
)
75 char *path
, *p
, *name
;
80 /* Generate the new process. */
87 /* The call was successful. Store the PID if necessary. */
95 flags
= attrp
== NULL
? 0 : attrp
->__flags
;
97 /* Set signal mask. */
98 if ((flags
& POSIX_SPAWN_SETSIGMASK
) != 0
99 && __sigprocmask (SIG_SETMASK
, &attrp
->__ss
, NULL
) != 0)
102 /* Set signal default action. */
103 if ((flags
& POSIX_SPAWN_SETSIGDEF
) != 0)
105 /* We have to iterate over all signals. This could possibly be
106 done better but it requires system specific solutions since
107 the sigset_t data type can be very different on different
112 memset (&sa
, '\0', sizeof (sa
));
113 sa
.sa_handler
= SIG_DFL
;
115 for (sig
= 1; sig
<= _NSIG
; ++sig
)
116 if (__sigismember (&attrp
->__sd
, sig
) != 0
117 && __sigaction (sig
, &sa
, NULL
) != 0)
122 #ifdef _POSIX_PRIORITY_SCHEDULING
123 /* Set the scheduling algorithm and parameters. */
124 if ((flags
& (POSIX_SPAWN_SETSCHEDPARAM
| POSIX_SPAWN_SETSCHEDULER
))
125 == POSIX_SPAWN_SETSCHEDPARAM
)
127 if (__sched_setparam (0, &attrp
->__sp
) == -1)
130 else if ((flags
& POSIX_SPAWN_SETSCHEDULER
) != 0)
132 if (__sched_setscheduler (0, attrp
->__policy
,
133 (flags
& POSIX_SPAWN_SETSCHEDPARAM
) != 0
134 ? &attrp
->__sp
: NULL
) == -1)
139 /* Set the process group ID. */
140 if ((flags
& POSIX_SPAWN_SETPGROUP
) != 0
141 && __setpgid (0, attrp
->__pgrp
) != 0)
144 /* Set the effective user and group IDs. */
145 if ((flags
& POSIX_SPAWN_RESETIDS
) != 0
146 && (seteuid (__getuid ()) != 0 || setegid (__getgid ()) != 0))
149 /* Execute the file actions. */
150 if (file_actions
!= NULL
)
154 for (cnt
= 0; cnt
< file_actions
->__used
; ++cnt
)
156 struct __spawn_action
*action
= &file_actions
->__actions
[cnt
];
161 if (__close (action
->action
.close_action
.fd
) != 0)
162 /* Signal the error. */
168 int new_fd
= __open64 (action
->action
.open_action
.path
,
169 action
->action
.open_action
.oflag
,
170 action
->action
.open_action
.mode
);
173 /* The `open' call failed. */
176 /* Make sure the desired file descriptor is used. */
177 if (new_fd
!= action
->action
.open_action
.fd
)
179 if (__dup2 (new_fd
, action
->action
.open_action
.fd
)
180 != action
->action
.open_action
.fd
)
181 /* The `dup2' call failed. */
184 if (__close (new_fd
) != 0)
185 /* The `close' call failed. */
192 if (__dup2 (action
->action
.dup2_action
.fd
,
193 action
->action
.dup2_action
.newfd
)
194 != action
->action
.dup2_action
.newfd
)
195 /* The `dup2' call failed. */
202 if (! use_path
|| strchr (file
, '/') != NULL
)
204 /* The FILE parameter is actually a path. */
205 __execve (file
, argv
, envp
);
207 if (errno
== ENOEXEC
)
208 script_execute (file
, argv
, envp
);
210 /* Oh, oh. `execve' returns. This is bad. */
214 /* We have to search for FILE on the path. */
215 path
= getenv ("PATH");
218 /* There is no `PATH' in the environment.
219 The default search path is the current directory
220 followed by the path `confstr' returns for `_CS_PATH'. */
221 len
= confstr (_CS_PATH
, (char *) NULL
, 0);
222 path
= (char *) __alloca (1 + len
);
224 (void) confstr (_CS_PATH
, path
+ 1, len
);
227 len
= strlen (file
) + 1;
228 pathlen
= strlen (path
);
229 name
= __alloca (pathlen
+ len
+ 1);
230 /* Copy the file name at the top. */
231 name
= (char *) memcpy (name
+ pathlen
+ 1, file
, len
);
232 /* And add the slash. */
241 p
= __strchrnul (path
, ':');
244 /* Two adjacent colons, or a colon at the beginning or the end
245 of `PATH' means to search the current directory. */
248 startp
= (char *) memcpy (name
- (p
- path
), path
, p
- path
);
250 /* Try to execute this name. If it works, execv will not return. */
251 __execve (startp
, argv
, envp
);
253 if (errno
== ENOEXEC
)
254 script_execute (startp
, argv
, envp
);
262 /* Those errors indicate the file is missing or not executable
263 by us, in which case we want to just try the next path
268 /* Some other error means we found an executable file, but
269 something went wrong executing it; return the error to our
274 while (*p
++ != '\0');
276 /* Return with an error. */