From 5046dbb4a7eba5eccfd258f92f4735c9ffc8d069 Mon Sep 17 00:00:00 2001 From: Zack Weinberg Date: Thu, 8 Jun 2017 15:39:03 -0400 Subject: Prepare for radical source tree reorganization. All top-level files and directories are moved into a temporary storage directory, REORG.TODO, except for files that will certainly still exist in their current form at top level when we're done (COPYING, COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which are moved to the new directory OldChangeLogs, instead), and the generated file INSTALL (which is just deleted; in the new order, there will be no generated files checked into version control). --- REORG.TODO/sysdeps/posix/system.c | 186 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 186 insertions(+) create mode 100644 REORG.TODO/sysdeps/posix/system.c (limited to 'REORG.TODO/sysdeps/posix/system.c') 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 + . */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + + +#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) -- cgit v1.2.1