| /* Pseudo implementation of waitid. |
| Copyright (C) 1997-2014 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Zack Weinberg <zack@rabi.phys.columbia.edu>, 1997. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library 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 |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <assert.h> |
| #include <errno.h> |
| #include <signal.h> |
| #define __need_NULL |
| #include <stddef.h> |
| #include <sys/wait.h> |
| #include <sys/types.h> |
| #include <sysdep-cancel.h> |
| |
| |
| #ifdef DO_WAITID |
| # define OUR_WAITID DO_WAITID |
| #elif !defined NO_DO_WAITID |
| # define OUR_WAITID do_waitid |
| #endif |
| |
| #ifdef OUR_WAITID |
| static int |
| OUR_WAITID (idtype_t idtype, id_t id, siginfo_t *infop, int options) |
| { |
| pid_t pid, child; |
| int status; |
| |
| switch (idtype) |
| { |
| case P_PID: |
| if(id <= 0) |
| goto invalid; |
| pid = (pid_t) id; |
| break; |
| case P_PGID: |
| if (id < 0 || id == 1) |
| goto invalid; |
| pid = (pid_t) -id; |
| break; |
| case P_ALL: |
| pid = -1; |
| break; |
| default: |
| invalid: |
| __set_errno (EINVAL); |
| return -1; |
| } |
| |
| /* Technically we're supposed to return EFAULT if infop is bogus, |
| but that would involve mucking with signals, which is |
| too much hassle. User will have to deal with SIGSEGV/SIGBUS. |
| We just check for a null pointer. */ |
| |
| if (infop == NULL) |
| { |
| __set_errno (EFAULT); |
| return -1; |
| } |
| |
| /* This emulation using waitpid cannot support the waitid modes in which |
| we do not reap the child, or match only stopped and not dead children. */ |
| if (0 |
| #ifdef WNOWAIT |
| || (options & WNOWAIT) |
| #endif |
| #ifdef WEXITED |
| || ((options & (WEXITED|WSTOPPED|WCONTINUED)) |
| != (WEXITED | (options & WUNTRACED))) |
| #endif |
| ) |
| { |
| __set_errno (ENOTSUP); |
| return -1; |
| } |
| |
| /* Note the waitid() is a cancellation point. But since we call |
| waitpid() which itself is a cancellation point we do not have |
| to do anything here. */ |
| child = __waitpid (pid, &status, |
| options |
| #ifdef WEXITED |
| &~ WEXITED |
| #endif |
| ); |
| |
| if (child == -1) |
| /* `waitpid' set `errno' for us. */ |
| return -1; |
| |
| if (child == 0) |
| { |
| /* The WHOHANG bit in OPTIONS is set and there are children available |
| but none has a status for us. The XPG docs do not mention this |
| case so we clear the `siginfo_t' struct and return successfully. */ |
| infop->si_signo = 0; |
| infop->si_code = 0; |
| return 0; |
| } |
| |
| /* Decode the status field and set infop members... */ |
| infop->si_signo = SIGCHLD; |
| infop->si_pid = child; |
| infop->si_errno = 0; |
| |
| if (WIFEXITED (status)) |
| { |
| infop->si_code = CLD_EXITED; |
| infop->si_status = WEXITSTATUS (status); |
| } |
| else if (WIFSIGNALED (status)) |
| { |
| infop->si_code = WCOREDUMP (status) ? CLD_DUMPED : CLD_KILLED; |
| infop->si_status = WTERMSIG (status); |
| } |
| else if (WIFSTOPPED (status)) |
| { |
| infop->si_code = CLD_STOPPED; |
| infop->si_status = WSTOPSIG (status); |
| } |
| #ifdef WIFCONTINUED |
| else if (WIFCONTINUED (status)) |
| { |
| infop->si_code = CLD_CONTINUED; |
| infop->si_status = SIGCONT; |
| } |
| #endif |
| else |
| /* Can't happen. */ |
| assert (! "What?"); |
| |
| return 0; |
| } |
| #endif |
| |
| |
| int |
| __waitid (idtype, id, infop, options) |
| idtype_t idtype; |
| id_t id; |
| siginfo_t *infop; |
| int options; |
| { |
| if (SINGLE_THREAD_P) |
| return do_waitid (idtype, id, infop, options); |
| |
| int oldtype = LIBC_CANCEL_ASYNC (); |
| |
| int result = do_waitid (idtype, id, infop, options); |
| |
| LIBC_CANCEL_RESET (oldtype); |
| |
| return result; |
| } |
| weak_alias (__waitid, waitid) |
| strong_alias (__waitid, __libc_waitid) |