src/w_file_stdc.c

   1 // Emacs style mode select   -*- C++ -*-
   2 //-----------------------------------------------------------------------------
   3 //
   4 // Copyright(C) 1993-1996 Id Software, Inc.
   5 // Copyright(C) 2008 Simon Howard
   6 //
   7 // This program is free software; you can redistribute it and/or
   8 // modify it under the terms of the GNU General Public License
   9 // as published by the Free Software Foundation; either version 2
  10 // of the License, or (at your option) any later version.
  11 //
  12 // This program is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16 //
  17 // You should have received a copy of the GNU General Public License
  18 // along with this program; if not, write to the Free Software
  19 // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  20 // 02111-1307, USA.
  21 //
  22 // DESCRIPTION:
  23 //      WAD I/O functions.
  24 //
  25 //-----------------------------------------------------------------------------
  26
  27 #include <stdio.h>
  28
  29 #include "m_misc.h"
  30 #include "w_file.h"
  31 #include "z_zone.h"
  32
  33 typedef struct
  34 {
  35     wad_file_t wad;
  36     FILE *fstream;
  37 } stdc_wad_file_t;
  38
  39 extern wad_file_class_t stdc_wad_file;
  40
  41 static wad_file_t *W_StdC_OpenFile(char *path)
  42 {
  43     stdc_wad_file_t *result;
  44     FILE *fstream;
  45
  46     fstream = fopen(path, "rb");
  47
  48     if (fstream == NULL)
  49     {
  50         return NULL;
  51     }
  52
  53     // Create a new stdc_wad_file_t to hold the file handle.
  54
  55     result = Z_Malloc(sizeof(stdc_wad_file_t), PU_STATIC, 0);
  56     result->wad.file_class = &stdc_wad_file;
  57     result->wad.mapped = NULL;
  58     result->wad.length = M_FileLength(fstream);
  59     result->fstream = fstream;
  60
  61     return &result->wad;
  62 }
  63
  64 static void W_StdC_CloseFile(wad_file_t *wad)
  65 {
  66     stdc_wad_file_t *stdc_wad;
  67
  68     stdc_wad = (stdc_wad_file_t *) wad;
  69
  70     fclose(stdc_wad->fstream);
  71     Z_Free(stdc_wad);
  72 }
  73
  74 // Read data from the specified position in the file into the
  75 // provided buffer.  Returns the number of bytes read.
  76
  77 size_t W_StdC_Read(wad_file_t *wad, unsigned int offset,
  78                    void *buffer, size_t buffer_len)
  79 {
  80     stdc_wad_file_t *stdc_wad;
  81     size_t result;
  82
  83     stdc_wad = (stdc_wad_file_t *) wad;
  84
  85     // Jump to the specified position in the file.
  86
  87     fseek(stdc_wad->fstream, offset, SEEK_SET);
  88
  89     // Read into the buffer.
  90
  91     result = fread(buffer, 1, buffer_len, stdc_wad->fstream);
  92
  93     return result;
  94 }
  95
  96
  97 wad_file_class_t stdc_wad_file =
  98 {
  99     W_StdC_OpenFile,
 100     W_StdC_CloseFile,
 101     W_StdC_Read,
 102 };
 103
 104