diff options
Diffstat (limited to 'REORG.TODO/sysdeps/posix/system.c')
| -rw-r--r-- | REORG.TODO/sysdeps/posix/system.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/posix/system.c b/REORG.TODO/sysdeps/posix/system.c new file mode 100644 index 0000000000..d49cc3f01c --- /dev/null +++ b/REORG.TODO/sysdeps/posix/system.c @@ -0,0 +1,186 @@ +/* Copyright (C) 1991-2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + 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 <errno.h> +#include <signal.h> +#include <stddef.h> +#include <stdlib.h> +#include <unistd.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <libc-lock.h> +#include <sysdep-cancel.h> + + +#define SHELL_PATH "/bin/sh" /* Path of the shell. */ +#define SHELL_NAME "sh" /* Name to give it. */ + + +#ifdef _LIBC_REENTRANT +static struct sigaction intr, quit; +static int sa_refcntr; +__libc_lock_define_initialized (static, lock); + +# define DO_LOCK() __libc_lock_lock (lock) +# define DO_UNLOCK() __libc_lock_unlock (lock) +# define INIT_LOCK() ({ __libc_lock_init (lock); sa_refcntr = 0; }) +# define ADD_REF() sa_refcntr++ +# define SUB_REF() --sa_refcntr +#else +# define DO_LOCK() +# define DO_UNLOCK() +# define INIT_LOCK() +# define ADD_REF() 0 +# define SUB_REF() 0 +#endif + + +/* Execute LINE as a shell command, returning its status. */ +static int +do_system (const char *line) +{ + int status, save; + pid_t pid; + struct sigaction sa; +#ifndef _LIBC_REENTRANT + struct sigaction intr, quit; +#endif + sigset_t omask; + + sa.sa_handler = SIG_IGN; + sa.sa_flags = 0; + __sigemptyset (&sa.sa_mask); + + DO_LOCK (); + if (ADD_REF () == 0) + { + if (__sigaction (SIGINT, &sa, &intr) < 0) + { + (void) SUB_REF (); + goto out; + } + if (__sigaction (SIGQUIT, &sa, &quit) < 0) + { + save = errno; + (void) SUB_REF (); + goto out_restore_sigint; + } + } + DO_UNLOCK (); + + /* We reuse the bitmap in the 'sa' structure. */ + __sigaddset (&sa.sa_mask, SIGCHLD); + save = errno; + if (__sigprocmask (SIG_BLOCK, &sa.sa_mask, &omask) < 0) + { +#ifndef _LIBC + if (errno == ENOSYS) + __set_errno (save); + else +#endif + { + DO_LOCK (); + if (SUB_REF () == 0) + { + save = errno; + (void) __sigaction (SIGQUIT, &quit, (struct sigaction *) NULL); + out_restore_sigint: + (void) __sigaction (SIGINT, &intr, (struct sigaction *) NULL); + __set_errno (save); + } + out: + DO_UNLOCK (); + return -1; + } + } + +#ifdef CLEANUP_HANDLER + CLEANUP_HANDLER; +#endif + +#ifdef FORK + pid = FORK (); +#else + pid = __fork (); +#endif + if (pid == (pid_t) 0) + { + /* Child side. */ + const char *new_argv[4]; + new_argv[0] = SHELL_NAME; + new_argv[1] = "-c"; + new_argv[2] = line; + new_argv[3] = NULL; + + /* Restore the signals. */ + (void) __sigaction (SIGINT, &intr, (struct sigaction *) NULL); + (void) __sigaction (SIGQUIT, &quit, (struct sigaction *) NULL); + (void) __sigprocmask (SIG_SETMASK, &omask, (sigset_t *) NULL); + INIT_LOCK (); + + /* Exec the shell. */ + (void) __execve (SHELL_PATH, (char *const *) new_argv, __environ); + _exit (127); + } + else if (pid < (pid_t) 0) + /* The fork failed. */ + status = -1; + else + /* Parent side. */ + { + /* Note the system() is a cancellation point. But since we call + waitpid() which itself is a cancellation point we do not + have to do anything here. */ + if (TEMP_FAILURE_RETRY (__waitpid (pid, &status, 0)) != pid) + status = -1; + } + +#ifdef CLEANUP_HANDLER + CLEANUP_RESET; +#endif + + save = errno; + DO_LOCK (); + if ((SUB_REF () == 0 + && (__sigaction (SIGINT, &intr, (struct sigaction *) NULL) + | __sigaction (SIGQUIT, &quit, (struct sigaction *) NULL)) != 0) + || __sigprocmask (SIG_SETMASK, &omask, (sigset_t *) NULL) != 0) + { +#ifndef _LIBC + /* glibc cannot be used on systems without waitpid. */ + if (errno == ENOSYS) + __set_errno (save); + else +#endif + status = -1; + } + DO_UNLOCK (); + + return status; +} + +int +__libc_system (const char *line) +{ + if (line == NULL) + /* Check that we have a command processor available. It might + not be available after a chroot(), for example. */ + return do_system ("exit 0") == 0; + + return do_system (line); +} +weak_alias (__libc_system, system) |