1 /* Copyright (C) 1993,1994,1997-1999,2000,2002 Free Software Foundation, Inc. 2 This file is part of the GNU C Library. 3 4 The GNU C Library is free software; you can redistribute it and/or 5 modify it under the terms of the GNU Lesser General Public 6 License as published by the Free Software Foundation; either 7 version 2.1 of the License, or (at your option) any later version. 8 9 The GNU C Library is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 Lesser General Public License for more details. 13 14 You should have received a copy of the GNU Lesser General Public 15 License along with the GNU C Library; if not, write to the Free 16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 17 02111-1307 USA. 18 19 As a special exception, if you link the code in this file with 20 files compiled with a GNU compiler to produce an executable, 21 that does not cause the resulting executable to be covered by 22 the GNU Lesser General Public License. This exception does not 23 however invalidate any other reasons why the executable file 24 might be covered by the GNU Lesser General Public License. 25 This exception applies to code released by its copyright holders 26 in files containing the exception. 27 */ 28 29 30 #include "libioP.h" 31 #include <stdlib.h> 32 #include <fcntl.h> 33 34 #ifdef _LIBC 35 # include <shlib-compat.h> 36 #endif 37 38 39 _IO_FILE * 40 _IO_new_fdopen (int fd, const char *mode) 41 { 42 int read_write; 43 int posix_mode = 0; 44 struct locked_FILE 45 { 46 struct _IO_FILE_plus fp; 47 #ifdef _IO_MTSAFE_IO 48 _IO_lock_t lock; 49 #endif 50 struct _IO_wide_data wd; 51 } *new_f; 52 int fd_flags; 53 int i; 54 int use_mmap = 0; 55 56 switch (*mode) 57 { 58 case 'r': 59 read_write = _IO_NO_WRITES; 60 break; 61 case 'w': 62 read_write = _IO_NO_READS; 63 break; 64 case 'a': 65 posix_mode = O_APPEND; 66 read_write = _IO_NO_READS|_IO_IS_APPENDING; 67 break; 68 default: 69 MAYBE_SET_EINVAL; 70 return NULL; 71 } 72 for (i = 1; i < 5; ++i) 73 { 74 switch (*++mode) 75 { 76 case '\0': 77 break; 78 case '+': 79 read_write &= _IO_IS_APPENDING; 80 break; 81 case 'm': 82 use_mmap = 1; 83 continue; 84 case 'x': 85 case 'b': 86 default: 87 /* Ignore */ 88 continue; 89 } 90 break; 91 } 92 #ifdef F_GETFL 93 fd_flags = fcntl(fd, F_GETFL); 94 #ifndef O_ACCMODE 95 #define O_ACCMODE (O_RDONLY|O_WRONLY|O_RDWR) 96 #endif 97 if (fd_flags == -1) 98 return NULL; 99 100 if (((fd_flags & O_ACCMODE) == O_RDONLY && !(read_write & _IO_NO_WRITES)) 101 || ((fd_flags & O_ACCMODE) == O_WRONLY && !(read_write & _IO_NO_READS))) 102 { 103 MAYBE_SET_EINVAL; 104 return NULL; 105 } 106 107 /* The May 93 draft of P1003.4/D14.1 (redesignated as 1003.1b) 108 [System Application Program Interface (API) Amendment 1: 109 Realtime Extensions], Rationale B.8.3.3 110 Open a Stream on a File Descriptor says: 111 112 Although not explicitly required by POSIX.1, a good 113 implementation of append ("a") mode would cause the 114 O_APPEND flag to be set. 115 116 (Historical implementations [such as Solaris2] do a one-time 117 seek in fdopen.) 118 119 However, we do not turn O_APPEND off if the mode is "w" (even 120 though that would seem consistent) because that would be more 121 likely to break historical programs. 122 */ 123 if ((posix_mode & O_APPEND) && !(fd_flags & O_APPEND)) 124 { 125 #ifdef F_SETFL 126 if (fcntl(fd, F_SETFL, fd_flags | O_APPEND) == -1) 127 #endif 128 return NULL; 129 } 130 #endif 131 132 new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE)); 133 if (new_f == NULL) 134 return NULL; 135 #ifdef _IO_MTSAFE_IO 136 new_f->fp.file._lock = &new_f->lock; 137 #endif 138 /* Set up initially to use the `maybe_mmap' jump tables rather than using 139 __fopen_maybe_mmap to do it, because we need them in place before we 140 call _IO_file_attach or else it will allocate a buffer immediately. */ 141 _IO_no_init (&new_f->fp.file, 0, 0, &new_f->wd, 142 #ifdef _G_HAVE_MMAP 143 (use_mmap && (read_write & _IO_NO_WRITES)) 144 ? &_IO_wfile_jumps_maybe_mmap : 145 #endif 146 &INTUSE(_IO_wfile_jumps)); 147 _IO_JUMPS (&new_f->fp) = 148 #ifdef _G_HAVE_MMAP 149 (use_mmap && (read_write & _IO_NO_WRITES)) ? &_IO_file_jumps_maybe_mmap : 150 #endif 151 &INTUSE(_IO_file_jumps); 152 INTUSE(_IO_file_init) (&new_f->fp); 153 #if !_IO_UNIFIED_JUMPTABLES 154 new_f->fp.vtable = NULL; 155 #endif 156 if (INTUSE(_IO_file_attach) ((_IO_FILE *) &new_f->fp, fd) == NULL) 157 { 158 INTUSE(_IO_setb) (&new_f->fp.file, NULL, NULL, 0); 159 INTUSE(_IO_un_link) (&new_f->fp); 160 free (new_f); 161 return NULL; 162 } 163 new_f->fp.file._flags &= ~_IO_DELETE_DONT_CLOSE; 164 165 new_f->fp.file._IO_file_flags = 166 _IO_mask_flags (&new_f->fp.file, read_write, 167 _IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING); 168 169 return &new_f->fp.file; 170 } 171 INTDEF2(_IO_new_fdopen, _IO_fdopen) 172 173 strong_alias (_IO_new_fdopen, __new_fdopen) 174 versioned_symbol (libc, _IO_new_fdopen, _IO_fdopen, GLIBC_2_1); 175 versioned_symbol (libc, __new_fdopen, fdopen, GLIBC_2_1); 176