share/fs_rwops.c

   1 /*
   2  * Copyright (C) 2003-2010 Neverball authors
   3  *
   4  * NEVERBALL is  free software; you can redistribute  it and/or modify
   5  * it under the  terms of the GNU General  Public License as published
   6  * by the Free  Software Foundation; either version 2  of the License,
   7  * or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT  ANY  WARRANTY;  without   even  the  implied  warranty  of
  11  * MERCHANTABILITY or  FITNESS FOR A PARTICULAR PURPOSE.   See the GNU
  12  * General Public License for more details.
  13  */
  14
  15 #include "fs_rwops.h"
  16
  17 static Sint64 rwops_seek(SDL_RWops *ctx, Sint64 offset, int whence)
  18 {
  19     fs_file fh = ctx->hidden.unknown.data1;
  20     return fs_seek(fh, offset, whence) ? fs_tell(fh) : -1;
  21 }
  22
  23 static size_t rwops_read(SDL_RWops *ctx, void *ptr, size_t size, size_t maxnum)
  24 {
  25     return fs_read(ptr, size, maxnum, ctx->hidden.unknown.data1);
  26 }
  27
  28 static size_t rwops_write(SDL_RWops *ctx, const void *ptr, size_t size, size_t num)
  29 {
  30     return fs_write(ptr, size, num, ctx->hidden.unknown.data1);
  31 }
  32
  33 static int rwops_close(SDL_RWops *ctx)
  34 {
  35     fs_file fh = ctx->hidden.unknown.data1;
  36
  37     if (!fs_close(fh))
  38         return -1;
  39
  40     SDL_FreeRW(ctx);
  41     return 0;
  42 }
  43
  44 SDL_RWops *fs_rwops_make(fs_file fh)
  45 {
  46     SDL_RWops *ctx;
  47
  48     if ((ctx = SDL_AllocRW()))
  49     {
  50         ctx->seek  = rwops_seek;
  51         ctx->read  = rwops_read;
  52         ctx->write = rwops_write;
  53         ctx->close = rwops_close;
  54
  55         ctx->hidden.unknown.data1 = fh;
  56     }
  57
  58     return ctx;
  59 }
  60
  61 SDL_RWops *fs_rwops_open(const char *path, const char *mode)
  62 {
  63     fs_file fh;
  64
  65     if ((fh = fs_open(path, mode)))
  66         return fs_rwops_make(fh);
  67
  68     return NULL;
  69 }