diff options
author | Sergey Poznyakoff <gray@gnu.org.ua> | 2007-06-27 13:46:15 +0000 |
---|---|---|
committer | Sergey Poznyakoff <gray@gnu.org.ua> | 2007-06-27 13:46:15 +0000 |
commit | c3d4fee823c6e4fdc96698b952ec7346f298ce81 (patch) | |
tree | c4566259fb25e6ec1cef732abd4731f86c4cc22a /lib | |
parent | a0fb51e136d3df620eb3189683aae90b25bd8dd7 (diff) | |
download | tar-c3d4fee823c6e4fdc96698b952ec7346f298ce81.tar.gz |
Restore after an accidental remove
Diffstat (limited to 'lib')
-rw-r--r-- | lib/waitpid.c | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/lib/waitpid.c b/lib/waitpid.c new file mode 100644 index 00000000..eab9430b --- /dev/null +++ b/lib/waitpid.c @@ -0,0 +1,75 @@ +/* Emulate waitpid on systems that just have wait. + Copyright 1994, 1995, 1998, 1999, 2007 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; see the file COPYING. + If not, write to the Free Software Foundation, + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + +#if HAVE_CONFIG_H +# include <config.h> +#endif + +#include <sys/types.h> +#include <sys/stat.h> + +#include <errno.h> +#ifndef errno +extern int errno; +#endif + +#define WAITPID_CHILDREN 8 +static pid_t waited_pid[WAITPID_CHILDREN]; +static int waited_status[WAITPID_CHILDREN]; + +pid_t +waitpid (pid_t pid, int *stat_loc, int options) +{ + int i; + pid_t p; + + if (!options && (pid == -1 || 0 < pid)) + { + /* If we have already waited for this child, return it immediately. */ + for (i = 0; i < WAITPID_CHILDREN; i++) + { + p = waited_pid[i]; + if (p && (p == pid || pid == -1)) + { + waited_pid[i] = 0; + goto success; + } + } + + /* The child has not returned yet; wait for it, accumulating status. */ + for (i = 0; i < WAITPID_CHILDREN; i++) + if (! waited_pid[i]) + { + p = wait (&waited_status[i]); + if (p < 0) + return p; + if (p == pid || pid == -1) + goto success; + waited_pid[i] = p; + } + } + + /* We cannot emulate this wait call, e.g. because of too many children. */ + errno = EINVAL; + return -1; + +success: + if (stat_loc) + *stat_loc = waited_status[i]; + return p; +} |