diff options
Diffstat (limited to 'REORG.TODO/libio/iofdopen.c')
| -rw-r--r-- | REORG.TODO/libio/iofdopen.c | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/REORG.TODO/libio/iofdopen.c b/REORG.TODO/libio/iofdopen.c new file mode 100644 index 0000000000..2a1df4680a --- /dev/null +++ b/REORG.TODO/libio/iofdopen.c @@ -0,0 +1,187 @@ +/* Copyright (C) 1993-2017 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/>. + + As a special exception, if you link the code in this file with + files compiled with a GNU compiler to produce an executable, + that does not cause the resulting executable to be covered by + the GNU Lesser General Public License. This exception does not + however invalidate any other reasons why the executable file + might be covered by the GNU Lesser General Public License. + This exception applies to code released by its copyright holders + in files containing the exception. */ + +#include <stdlib.h> +#include "libioP.h" +#include <fcntl.h> + +#ifdef _LIBC +# include <shlib-compat.h> +#endif + +#ifndef _IO_fcntl +#ifdef _LIBC +#define _IO_fcntl __fcntl +#else +#define _IO_fcntl fcntl +#endif +#endif + +_IO_FILE * +_IO_new_fdopen (int fd, const char *mode) +{ + int read_write; + struct locked_FILE + { + struct _IO_FILE_plus fp; +#ifdef _IO_MTSAFE_IO + _IO_lock_t lock; +#endif + struct _IO_wide_data wd; + } *new_f; + int i; + int use_mmap = 0; + + /* Decide whether we modify the offset of the file we attach to and seek to + the end of file. We only do this if the mode is 'a' and if the file + descriptor did not have O_APPEND in its flags already. */ + bool do_seek = false; + + switch (*mode) + { + case 'r': + read_write = _IO_NO_WRITES; + break; + case 'w': + read_write = _IO_NO_READS; + break; + case 'a': + read_write = _IO_NO_READS|_IO_IS_APPENDING; + break; + default: + MAYBE_SET_EINVAL; + return NULL; + } + for (i = 1; i < 5; ++i) + { + switch (*++mode) + { + case '\0': + break; + case '+': + read_write &= _IO_IS_APPENDING; + break; + case 'm': + use_mmap = 1; + continue; + case 'x': + case 'b': + default: + /* Ignore */ + continue; + } + break; + } +#ifdef F_GETFL + int fd_flags = _IO_fcntl (fd, F_GETFL); +#ifndef O_ACCMODE +#define O_ACCMODE (O_RDONLY|O_WRONLY|O_RDWR) +#endif + if (fd_flags == -1) + return NULL; + + if (((fd_flags & O_ACCMODE) == O_RDONLY && !(read_write & _IO_NO_WRITES)) + || ((fd_flags & O_ACCMODE) == O_WRONLY && !(read_write & _IO_NO_READS))) + { + MAYBE_SET_EINVAL; + return NULL; + } + + /* The May 93 draft of P1003.4/D14.1 (redesignated as 1003.1b) + [System Application Program Interface (API) Amendment 1: + Realtime Extensions], Rationale B.8.3.3 + Open a Stream on a File Descriptor says: + + Although not explicitly required by POSIX.1, a good + implementation of append ("a") mode would cause the + O_APPEND flag to be set. + + (Historical implementations [such as Solaris2] do a one-time + seek in fdopen.) + + However, we do not turn O_APPEND off if the mode is "w" (even + though that would seem consistent) because that would be more + likely to break historical programs. + */ + if ((read_write & _IO_IS_APPENDING) && !(fd_flags & O_APPEND)) + { + do_seek = true; +#ifdef F_SETFL + if (_IO_fcntl (fd, F_SETFL, fd_flags | O_APPEND) == -1) +#endif + return NULL; + } +#endif + + new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE)); + if (new_f == NULL) + return NULL; +#ifdef _IO_MTSAFE_IO + new_f->fp.file._lock = &new_f->lock; +#endif + _IO_no_init (&new_f->fp.file, 0, 0, &new_f->wd, +#ifdef _G_HAVE_MMAP + (use_mmap && (read_write & _IO_NO_WRITES)) + ? &_IO_wfile_jumps_maybe_mmap : +#endif + &_IO_wfile_jumps); + _IO_JUMPS (&new_f->fp) = +#ifdef _G_HAVE_MMAP + (use_mmap && (read_write & _IO_NO_WRITES)) ? &_IO_file_jumps_maybe_mmap : +#endif + &_IO_file_jumps; + _IO_new_file_init_internal (&new_f->fp); +#if !_IO_UNIFIED_JUMPTABLES + new_f->fp.vtable = NULL; +#endif + /* We only need to record the fd because _IO_file_init_internal will + have unset the offset. It is important to unset the cached + offset because the real offset in the file could change between + now and when the handle is activated and we would then mislead + ftell into believing that we have a valid offset. */ + new_f->fp.file._fileno = fd; + new_f->fp.file._flags &= ~_IO_DELETE_DONT_CLOSE; + + _IO_mask_flags (&new_f->fp.file, read_write, + _IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING); + + /* For append mode, set the file offset to the end of the file if we added + O_APPEND to the file descriptor flags. Don't update the offset cache + though, since the file handle is not active. */ + if (do_seek && ((read_write & (_IO_IS_APPENDING | _IO_NO_READS)) + == (_IO_IS_APPENDING | _IO_NO_READS))) + { + _IO_off64_t new_pos = _IO_SYSSEEK (&new_f->fp.file, 0, _IO_seek_end); + if (new_pos == _IO_pos_BAD && errno != ESPIPE) + return NULL; + } + return &new_f->fp.file; +} +libc_hidden_ver (_IO_new_fdopen, _IO_fdopen) + +strong_alias (_IO_new_fdopen, __new_fdopen) +versioned_symbol (libc, _IO_new_fdopen, _IO_fdopen, GLIBC_2_1); +versioned_symbol (libc, __new_fdopen, fdopen, GLIBC_2_1); |