Branch data     Line data    Source code

       1                 :            : /* read-file.c -- read file contents into a string
       2                 :            :    Copyright (C) 2006, 2009, 2010 Free Software Foundation, Inc.
       3                 :            :    Written by Simon Josefsson and Bruno Haible.
       4                 :            : 
       5                 :            :    This program is free software; you can redistribute it and/or modify
       6                 :            :    it under the terms of the GNU General Public License as published by
       7                 :            :    the Free Software Foundation; either version 3, or (at your option)
       8                 :            :    any later version.
       9                 :            : 
      10                 :            :    This program is distributed in the hope that it will be useful,
      11                 :            :    but WITHOUT ANY WARRANTY; without even the implied warranty of
      12                 :            :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      13                 :            :    GNU General Public License for more details.
      14                 :            : 
      15                 :            :    You should have received a copy of the GNU General Public License
      16                 :            :    along with this program; if not, write to the Free Software Foundation,
      17                 :            :    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
      18                 :            : 
      19                 :            : #include <config.h>
      20                 :            : 
      21                 :            : #include "read-file.h"
      22                 :            : 
      23                 :            : /* Get realloc, free. */
      24                 :            : #include <stdlib.h>
      25                 :            : 
      26                 :            : /* Get errno. */
      27                 :            : #include <errno.h>
      28                 :            : 
      29                 :            : /* Read a STREAM and return a newly allocated string with the content,
      30                 :            :    and set *LENGTH to the length of the string.  The string is
      31                 :            :    zero-terminated, but the terminating zero byte is not counted in
      32                 :            :    *LENGTH.  On errors, *LENGTH is undefined, errno preserves the
      33                 :            :    values set by system functions (if any), and NULL is returned. */
      34                 :            : char *
      35                 :          2 : fread_file (FILE * stream, size_t * length)
      36                 :            : {
      37                 :          2 :   char *buf = NULL;
      38                 :          2 :   size_t alloc = 0;
      39                 :          2 :   size_t size = 0;
      40                 :            :   int save_errno;
      41                 :            : 
      42                 :            :   for (;;)
      43                 :            :     {
      44                 :            :       size_t count;
      45                 :            :       size_t requested;
      46                 :            : 
      47         [ +  - ]:          2 :       if (size + BUFSIZ + 1 > alloc)
      48                 :            :         {
      49                 :            :           char *new_buf;
      50                 :            : 
      51                 :          2 :           alloc += alloc / 2;
      52         [ +  - ]:          2 :           if (alloc < size + BUFSIZ + 1)
      53                 :          2 :             alloc = size + BUFSIZ + 1;
      54                 :            : 
      55                 :          2 :           new_buf = realloc (buf, alloc);
      56         [ -  + ]:          2 :           if (!new_buf)
      57                 :            :             {
      58                 :          0 :               save_errno = errno;
      59                 :          0 :               break;
      60                 :            :             }
      61                 :            : 
      62                 :          2 :           buf = new_buf;
      63                 :            :         }
      64                 :            : 
      65                 :          2 :       requested = alloc - size - 1;
      66                 :          2 :       count = fread (buf + size, 1, requested, stream);
      67                 :          2 :       size += count;
      68                 :            : 
      69         [ +  - ]:          2 :       if (count != requested)
      70                 :            :         {
      71                 :          2 :           save_errno = errno;
      72         [ -  + ]:          2 :           if (ferror (stream))
      73                 :          0 :             break;
      74                 :          2 :           buf[size] = '\0';
      75                 :          2 :           *length = size;
      76                 :          2 :           return buf;
      77                 :            :         }
      78                 :          0 :     }
      79                 :            : 
      80                 :          0 :   free (buf);
      81                 :          0 :   errno = save_errno;
      82                 :          2 :   return NULL;
      83                 :            : }
      84                 :            : 
      85                 :            : static char *
      86                 :          2 : internal_read_file (const char *filename, size_t * length, const char *mode)
      87                 :            : {
      88                 :          2 :   FILE *stream = fopen (filename, mode);
      89                 :            :   char *out;
      90                 :            :   int save_errno;
      91                 :            : 
      92         [ -  + ]:          2 :   if (!stream)
      93                 :          0 :     return NULL;
      94                 :            : 
      95                 :          2 :   out = fread_file (stream, length);
      96                 :            : 
      97                 :          2 :   save_errno = errno;
      98                 :            : 
      99         [ -  + ]:          2 :   if (fclose (stream) != 0)
     100                 :            :     {
     101         [ #  # ]:          0 :       if (out)
     102                 :            :         {
     103                 :          0 :           save_errno = errno;
     104                 :          0 :           free (out);
     105                 :            :         }
     106                 :          0 :       errno = save_errno;
     107                 :          0 :       return NULL;
     108                 :            :     }
     109                 :            : 
     110                 :          2 :   return out;
     111                 :            : }
     112                 :            : 
     113                 :            : /* Open and read the contents of FILENAME, and return a newly
     114                 :            :    allocated string with the content, and set *LENGTH to the length of
     115                 :            :    the string.  The string is zero-terminated, but the terminating
     116                 :            :    zero byte is not counted in *LENGTH.  On errors, *LENGTH is
     117                 :            :    undefined, errno preserves the values set by system functions (if
     118                 :            :    any), and NULL is returned.  */
     119                 :            : char *
     120                 :          0 : read_file (const char *filename, size_t * length)
     121                 :            : {
     122                 :          0 :   return internal_read_file (filename, length, "r");
     123                 :            : }
     124                 :            : 
     125                 :            : /* Open (on non-POSIX systems, in binary mode) and read the contents
     126                 :            :    of FILENAME, and return a newly allocated string with the content,
     127                 :            :    and set LENGTH to the length of the string.  The string is
     128                 :            :    zero-terminated, but the terminating zero byte is not counted in
     129                 :            :    the LENGTH variable.  On errors, *LENGTH is undefined, errno
     130                 :            :    preserves the values set by system functions (if any), and NULL is
     131                 :            :    returned.  */
     132                 :            : char *
     133                 :          2 : read_binary_file (const char *filename, size_t * length)
     134                 :            : {
     135                 :          2 :   return internal_read_file (filename, length, "rb");
     136                 :            : }