diff options
Diffstat (limited to 'libio/iopopen.c')
| -rw-r--r-- | libio/iopopen.c | 120 |
1 files changed, 96 insertions, 24 deletions
diff --git a/libio/iopopen.c b/libio/iopopen.c index d5c6305b09..1a5cc0f592 100644 --- a/libio/iopopen.c +++ b/libio/iopopen.c @@ -1,4 +1,4 @@ -/* Copyright (C) 1993, 1997-2002, 2003, 2004, 2007 +/* Copyright (C) 1993, 1997-2002, 2003, 2004, 2007, 2008 Free Software Foundation, Inc. This file is part of the GNU C Library. Written by Per Bothner <bothner@cygnus.com>. @@ -44,6 +44,7 @@ #endif #include <sys/types.h> #include <sys/wait.h> +#include <kernel-features.h> #ifndef _IO_fork #ifdef _LIBC @@ -56,15 +57,6 @@ extern _IO_pid_t _IO_fork (void) __THROW; #endif /* _IO_HAVE_SYS_WAIT */ -#ifndef _IO_pipe -#ifdef _LIBC -#define _IO_pipe __pipe -#else -#define _IO_pipe pipe -#endif -extern int _IO_pipe (int des[2]) __THROW; -#endif - #ifndef _IO_dup2 #ifdef _LIBC #define _IO_dup2 __dup2 @@ -127,45 +119,103 @@ _IO_new_proc_open (fp, command, mode) const char *mode; { #if _IO_HAVE_SYS_WAIT - volatile int read_or_write; - volatile int parent_end, child_end; + int read_or_write; + int parent_end, child_end; int pipe_fds[2]; _IO_pid_t child_pid; + + int do_read = 0; + int do_write = 0; + int do_cloexec = 0; + while (*mode != '\0') + switch (*mode++) + { + case 'r': + do_read = 1; + break; + case 'w': + do_write = 1; + break; + case 'e': + do_cloexec = 1; + break; + default: + errout: + __set_errno (EINVAL); + return NULL; + } + + if ((do_read ^ do_write) == 0) + goto errout; + if (_IO_file_is_open (fp)) return NULL; - if (_IO_pipe (pipe_fds) < 0) - return NULL; - if (mode[0] == 'r' && mode[1] == '\0') + +#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 + + if (do_read) { parent_end = pipe_fds[0]; child_end = pipe_fds[1]; read_or_write = _IO_NO_WRITES; } - else if (mode[0] == 'w' && mode[1] == '\0') + else { parent_end = pipe_fds[1]; child_end = pipe_fds[0]; read_or_write = _IO_NO_READS; } - else - { - _IO_close (pipe_fds[0]); - _IO_close (pipe_fds[1]); - __set_errno (EINVAL); - return NULL; - } + ((_IO_proc_file *) fp)->pid = child_pid = _IO_fork (); if (child_pid == 0) { - int child_std_end = mode[0] == 'r' ? 1 : 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 + 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 /* 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." */ @@ -189,6 +239,28 @@ _IO_new_proc_open (fp, command, mode) _IO_close (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 + } + _IO_fileno (fp) = parent_end; /* Link into proc_file_chain. */ |