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-rw-r--r--libio/iopopen.c179
1 files changed, 43 insertions, 136 deletions
diff --git a/libio/iopopen.c b/libio/iopopen.c
index 9ddde23494..2eff45b4c8 100644
--- a/libio/iopopen.c
+++ b/libio/iopopen.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1993-2016 Free Software Foundation, Inc.
+/* Copyright (C) 1993-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Written by Per Bothner <bothner@cygnus.com>.
@@ -25,68 +25,22 @@
This exception applies to code released by its copyright holders
in files containing the exception. */
-#ifndef _POSIX_SOURCE
-# define _POSIX_SOURCE
-#endif
#include "libioP.h"
#include <fcntl.h>
#include <signal.h>
#include <unistd.h>
#include <stdlib.h>
-#ifdef _LIBC
-# include <shlib-compat.h>
-# include <not-cancel.h>
-#endif
+#include <shlib-compat.h>
+#include <not-cancel.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <kernel-features.h>
-#ifndef _IO_fork
-#ifdef _LIBC
-#define _IO_fork __fork
-#else
-#define _IO_fork fork /* defined in libiberty, if needed */
-#endif
-extern _IO_pid_t _IO_fork (void) __THROW;
-#endif
-
-#ifndef _IO_dup2
-#ifdef _LIBC
-#define _IO_dup2 __dup2
-#else
-#define _IO_dup2 dup2
-#endif
-extern int _IO_dup2 (int fd, int fd2) __THROW;
-#endif
-
-#ifndef _IO_waitpid
-#ifdef _LIBC
-#define _IO_waitpid waitpid_not_cancel
-#else
-#define _IO_waitpid waitpid
-#endif
-#endif
-
-#ifndef _IO_execl
-#define _IO_execl execl
-#endif
-#ifndef _IO__exit
-#define _IO__exit _exit
-#endif
-
-#ifndef _IO_close
-#ifdef _LIBC
-#define _IO_close close_not_cancel
-#else
-#define _IO_close close
-#endif
-#endif
-
struct _IO_proc_file
{
struct _IO_FILE_plus file;
/* Following fields must match those in class procbuf (procbuf.h) */
- _IO_pid_t pid;
+ pid_t pid;
struct _IO_proc_file *next;
};
typedef struct _IO_proc_file _IO_proc_file;
@@ -105,13 +59,13 @@ unlock (void *not_used)
}
#endif
-_IO_FILE *
-_IO_new_proc_open (_IO_FILE *fp, const char *command, const char *mode)
+FILE *
+_IO_new_proc_open (FILE *fp, const char *command, const char *mode)
{
int read_or_write;
int parent_end, child_end;
int pipe_fds[2];
- _IO_pid_t child_pid;
+ pid_t child_pid;
int do_read = 0;
int do_write = 0;
@@ -140,29 +94,17 @@ _IO_new_proc_open (_IO_FILE *fp, const char *command, const char *mode)
if (_IO_file_is_open (fp))
return NULL;
-#ifdef O_CLOEXEC
-# ifndef __ASSUME_PIPE2
- if (__have_pipe2 >= 0)
-# endif
- {
- int r = __pipe2 (pipe_fds, O_CLOEXEC);
-# ifndef __ASSUME_PIPE2
- if (__have_pipe2 == 0)
- __have_pipe2 = r != -1 || errno != ENOSYS ? 1 : -1;
-
- if (__have_pipe2 > 0)
-# endif
- if (r < 0)
- return NULL;
- }
-#endif
-#ifndef __ASSUME_PIPE2
-# ifdef O_CLOEXEC
- if (__have_pipe2 < 0)
-# endif
- if (__pipe (pipe_fds) < 0)
- return NULL;
-#endif
+ /* Atomically set the O_CLOEXEC flag for the pipe end used by the
+ child process (to avoid leaking the file descriptor in case of a
+ concurrent fork). This is later reverted in the child process.
+ When popen returns, the parent pipe end can be O_CLOEXEC or not,
+ depending on the 'e' open mode, but there is only one flag which
+ controls both descriptors. The parent end is adjusted below,
+ after creating the child process. (In the child process, the
+ parent end should be closed on execve, so O_CLOEXEC remains set
+ there.) */
+ if (__pipe2 (pipe_fds, O_CLOEXEC) < 0)
+ return NULL;
if (do_read)
{
@@ -177,78 +119,46 @@ _IO_new_proc_open (_IO_FILE *fp, const char *command, const char *mode)
read_or_write = _IO_NO_READS;
}
- ((_IO_proc_file *) fp)->pid = child_pid = _IO_fork ();
+ ((_IO_proc_file *) fp)->pid = child_pid = __fork ();
if (child_pid == 0)
{
int child_std_end = do_read ? 1 : 0;
struct _IO_proc_file *p;
-#ifndef __ASSUME_PIPE2
- /* If we have pipe2 the descriptor is marked for close-on-exec. */
- _IO_close (parent_end);
-#endif
if (child_end != child_std_end)
- {
- _IO_dup2 (child_end, child_std_end);
-#ifndef __ASSUME_PIPE2
- _IO_close (child_end);
-#endif
- }
-#ifdef O_CLOEXEC
+ __dup2 (child_end, child_std_end);
else
- {
- /* The descriptor is already the one we will use. But it must
- not be marked close-on-exec. Undo the effects. */
-# ifndef __ASSUME_PIPE2
- if (__have_pipe2 > 0)
-# endif
- __fcntl (child_end, F_SETFD, 0);
- }
-#endif
+ /* The descriptor is already the one we will use. But it must
+ not be marked close-on-exec. Undo the effects. */
+ __fcntl (child_end, F_SETFD, 0);
/* POSIX.2: "popen() shall ensure that any streams from previous
popen() calls that remain open in the parent process are closed
in the new child process." */
for (p = proc_file_chain; p; p = p->next)
{
- int fd = _IO_fileno ((_IO_FILE *) p);
+ int fd = _IO_fileno ((FILE *) p);
/* If any stream from previous popen() calls has fileno
child_std_end, it has been already closed by the dup2 syscall
above. */
if (fd != child_std_end)
- _IO_close (fd);
+ __close_nocancel (fd);
}
- _IO_execl ("/bin/sh", "sh", "-c", command, (char *) 0);
- _IO__exit (127);
+ execl ("/bin/sh", "sh", "-c", command, (char *) 0);
+ _exit (127);
}
- _IO_close (child_end);
+ __close_nocancel (child_end);
if (child_pid < 0)
{
- _IO_close (parent_end);
+ __close_nocancel (parent_end);
return NULL;
}
- if (do_cloexec)
- {
-#ifndef __ASSUME_PIPE2
-# ifdef O_CLOEXEC
- if (__have_pipe2 < 0)
-# endif
- __fcntl (parent_end, F_SETFD, FD_CLOEXEC);
-#endif
- }
- else
- {
-#ifdef O_CLOEXEC
- /* Undo the effects of the pipe2 call which set the
- close-on-exec flag. */
-# ifndef __ASSUME_PIPE2
- if (__have_pipe2 > 0)
-# endif
- __fcntl (parent_end, F_SETFD, 0);
-#endif
- }
+ if (!do_cloexec)
+ /* Undo the effects of the pipe2 call which set the
+ close-on-exec flag. */
+ __fcntl (parent_end, F_SETFD, 0);
_IO_fileno (fp) = parent_end;
@@ -268,7 +178,7 @@ _IO_new_proc_open (_IO_FILE *fp, const char *command, const char *mode)
return fp;
}
-_IO_FILE *
+FILE *
_IO_new_popen (const char *command, const char *mode)
{
struct locked_FILE
@@ -278,7 +188,7 @@ _IO_new_popen (const char *command, const char *mode)
_IO_lock_t lock;
#endif
} *new_f;
- _IO_FILE *fp;
+ FILE *fp;
new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE));
if (new_f == NULL)
@@ -287,26 +197,23 @@ _IO_new_popen (const char *command, const char *mode)
new_f->fpx.file.file._lock = &new_f->lock;
#endif
fp = &new_f->fpx.file.file;
- _IO_init (fp, 0);
+ _IO_init_internal (fp, 0);
_IO_JUMPS (&new_f->fpx.file) = &_IO_proc_jumps;
- _IO_new_file_init (&new_f->fpx.file);
-#if !_IO_UNIFIED_JUMPTABLES
- new_f->fpx.file.vtable = NULL;
-#endif
+ _IO_new_file_init_internal (&new_f->fpx.file);
if (_IO_new_proc_open (fp, command, mode) != NULL)
- return (_IO_FILE *) &new_f->fpx.file;
+ return (FILE *) &new_f->fpx.file;
_IO_un_link (&new_f->fpx.file);
free (new_f);
return NULL;
}
int
-_IO_new_proc_close (_IO_FILE *fp)
+_IO_new_proc_close (FILE *fp)
{
/* This is not name-space clean. FIXME! */
int wstatus;
_IO_proc_file **ptr = &proc_file_chain;
- _IO_pid_t wait_pid;
+ pid_t wait_pid;
int status = -1;
/* Unlink from proc_file_chain. */
@@ -328,7 +235,7 @@ _IO_new_proc_close (_IO_FILE *fp)
_IO_cleanup_region_end (0);
#endif
- if (status < 0 || _IO_close (_IO_fileno(fp)) < 0)
+ if (status < 0 || __close_nocancel (_IO_fileno(fp)) < 0)
return -1;
/* POSIX.2 Rationale: "Some historical implementations either block
or ignore the signals SIGINT, SIGQUIT, and SIGHUP while waiting
@@ -336,7 +243,7 @@ _IO_new_proc_close (_IO_FILE *fp)
described in POSIX.2, such implementations are not conforming." */
do
{
- wait_pid = _IO_waitpid (((_IO_proc_file *) fp)->pid, &wstatus, 0);
+ wait_pid = __waitpid_nocancel (((_IO_proc_file *) fp)->pid, &wstatus, 0);
}
while (wait_pid == -1 && errno == EINTR);
if (wait_pid == -1)
@@ -344,7 +251,7 @@ _IO_new_proc_close (_IO_FILE *fp)
return wstatus;
}
-static const struct _IO_jump_t _IO_proc_jumps = {
+static const struct _IO_jump_t _IO_proc_jumps libio_vtable = {
JUMP_INIT_DUMMY,
JUMP_INIT(finish, _IO_new_file_finish),
JUMP_INIT(overflow, _IO_new_file_overflow),