misc/libphyslayer/physfsrwops.c
branchphysfslayer
changeset 8524 a65e9bcf0a03
parent 8522 1853628ae285
child 9309 7e8f91634f80
equal deleted inserted replaced
8522:1853628ae285 8524:a65e9bcf0a03
       
     1 /*
       
     2  * This code provides a glue layer between PhysicsFS and Simple Directmedia
       
     3  *  Layer's (SDL) RWops i/o abstraction.
       
     4  *
       
     5  * License: this code is public domain. I make no warranty that it is useful,
       
     6  *  correct, harmless, or environmentally safe.
       
     7  *
       
     8  * This particular file may be used however you like, including copying it
       
     9  *  verbatim into a closed-source project, exploiting it commercially, and
       
    10  *  removing any trace of my name from the source (although I hope you won't
       
    11  *  do that). I welcome enhancements and corrections to this file, but I do
       
    12  *  not require you to send me patches if you make changes. This code has
       
    13  *  NO WARRANTY.
       
    14  *
       
    15  * Unless otherwise stated, the rest of PhysicsFS falls under the zlib license.
       
    16  *  Please see LICENSE.txt in the root of the source tree.
       
    17  *
       
    18  * SDL 1.2 falls under the LGPL license. SDL 1.3+ is zlib, like PhysicsFS.
       
    19  *  You can get SDL at http://www.libsdl.org/
       
    20  *
       
    21  *  This file was written by Ryan C. Gordon. (icculus@icculus.org).
       
    22  */
       
    23 
       
    24 #include <stdio.h>  /* used for SEEK_SET, SEEK_CUR, SEEK_END ... */
       
    25 #include "physfsrwops.h"
       
    26 
       
    27 /* SDL's RWOPS interface changed a little in SDL 1.3... */
       
    28 #if defined(SDL_VERSION_ATLEAST)
       
    29 #if SDL_VERSION_ATLEAST(1, 3, 0)
       
    30 #define TARGET_SDL13 1
       
    31 #endif
       
    32 #endif
       
    33 
       
    34 #if TARGET_SDL13
       
    35 static long SDLCALL physfsrwops_seek(struct SDL_RWops *rw, long offset, int whence)
       
    36 #else
       
    37 static int physfsrwops_seek(SDL_RWops *rw, int offset, int whence)
       
    38 #endif
       
    39 {
       
    40     PHYSFS_File *handle = (PHYSFS_File *) rw->hidden.unknown.data1;
       
    41     PHYSFS_sint64 pos = 0;
       
    42 
       
    43     if (whence == SEEK_SET)
       
    44         pos = (PHYSFS_sint64) offset;
       
    45 
       
    46     else if (whence == SEEK_CUR)
       
    47     {
       
    48         const PHYSFS_sint64 current = PHYSFS_tell(handle);
       
    49         if (current == -1)
       
    50         {
       
    51             SDL_SetError("Can't find position in file: %s",
       
    52                           PHYSFS_getLastError());
       
    53             return -1;
       
    54         } /* if */
       
    55 
       
    56         if (offset == 0)  /* this is a "tell" call. We're done. */
       
    57         {
       
    58             #if TARGET_SDL13
       
    59             return (long) current;
       
    60             #else
       
    61             return (int) current;
       
    62             #endif
       
    63         } /* if */
       
    64 
       
    65         pos = current + ((PHYSFS_sint64) offset);
       
    66     } /* else if */
       
    67 
       
    68     else if (whence == SEEK_END)
       
    69     {
       
    70         const PHYSFS_sint64 len = PHYSFS_fileLength(handle);
       
    71         if (len == -1)
       
    72         {
       
    73             SDL_SetError("Can't find end of file: %s", PHYSFS_getLastError());
       
    74             return -1;
       
    75         } /* if */
       
    76 
       
    77         pos = len + ((PHYSFS_sint64) offset);
       
    78     } /* else if */
       
    79 
       
    80     else
       
    81     {
       
    82         SDL_SetError("Invalid 'whence' parameter.");
       
    83         return -1;
       
    84     } /* else */
       
    85 
       
    86     if ( pos < 0 )
       
    87     {
       
    88         SDL_SetError("Attempt to seek past start of file.");
       
    89         return -1;
       
    90     } /* if */
       
    91     
       
    92     if (!PHYSFS_seek(handle, (PHYSFS_uint64) pos))
       
    93     {
       
    94         SDL_SetError("PhysicsFS error: %s", PHYSFS_getLastError());
       
    95         return -1;
       
    96     } /* if */
       
    97 
       
    98     #if TARGET_SDL13
       
    99     return (long) pos;
       
   100     #else
       
   101     return (int) pos;
       
   102     #endif
       
   103 } /* physfsrwops_seek */
       
   104 
       
   105 
       
   106 #if TARGET_SDL13
       
   107 static size_t SDLCALL physfsrwops_read(struct SDL_RWops *rw, void *ptr,
       
   108                                        size_t size, size_t maxnum)
       
   109 #else
       
   110 static int physfsrwops_read(SDL_RWops *rw, void *ptr, int size, int maxnum)
       
   111 #endif
       
   112 {
       
   113     PHYSFS_File *handle = (PHYSFS_File *) rw->hidden.unknown.data1;
       
   114     const PHYSFS_uint64 readlen = (PHYSFS_uint64) (maxnum * size);
       
   115     const PHYSFS_sint64 rc = PHYSFS_readBytes(handle, ptr, readlen);
       
   116     if (rc != ((PHYSFS_sint64) readlen))
       
   117     {
       
   118         if (!PHYSFS_eof(handle)) /* not EOF? Must be an error. */
       
   119             SDL_SetError("PhysicsFS error: %s", PHYSFS_getLastError());
       
   120     } /* if */
       
   121 
       
   122     #if TARGET_SDL13
       
   123     return (size_t) rc;
       
   124     #else
       
   125     return (int) rc;
       
   126     #endif
       
   127 } /* physfsrwops_read */
       
   128 
       
   129 
       
   130 #if TARGET_SDL13
       
   131 static size_t SDLCALL physfsrwops_write(struct SDL_RWops *rw, const void *ptr,
       
   132                                         size_t size, size_t num)
       
   133 #else
       
   134 static int physfsrwops_write(SDL_RWops *rw, const void *ptr, int size, int num)
       
   135 #endif
       
   136 {
       
   137     PHYSFS_File *handle = (PHYSFS_File *) rw->hidden.unknown.data1;
       
   138     const PHYSFS_uint64 writelen = (PHYSFS_uint64) (num * size);
       
   139     const PHYSFS_sint64 rc = PHYSFS_writeBytes(handle, ptr, writelen);
       
   140     if (rc != ((PHYSFS_sint64) writelen))
       
   141         SDL_SetError("PhysicsFS error: %s", PHYSFS_getLastError());
       
   142 
       
   143     #if TARGET_SDL13
       
   144     return (size_t) rc;
       
   145     #else
       
   146     return (int) rc;
       
   147     #endif
       
   148 } /* physfsrwops_write */
       
   149 
       
   150 
       
   151 static int physfsrwops_close(SDL_RWops *rw)
       
   152 {
       
   153     PHYSFS_File *handle = (PHYSFS_File *) rw->hidden.unknown.data1;
       
   154     if (!PHYSFS_close(handle))
       
   155     {
       
   156         SDL_SetError("PhysicsFS error: %s", PHYSFS_getLastError());
       
   157         return -1;
       
   158     } /* if */
       
   159 
       
   160     SDL_FreeRW(rw);
       
   161     return 0;
       
   162 } /* physfsrwops_close */
       
   163 
       
   164 
       
   165 static SDL_RWops *create_rwops(PHYSFS_File *handle)
       
   166 {
       
   167     SDL_RWops *retval = NULL;
       
   168 
       
   169     if (handle == NULL)
       
   170         SDL_SetError("PhysicsFS error: %s", PHYSFS_getLastError());
       
   171     else
       
   172     {
       
   173         retval = SDL_AllocRW();
       
   174         if (retval != NULL)
       
   175         {
       
   176             retval->seek  = physfsrwops_seek;
       
   177             retval->read  = physfsrwops_read;
       
   178             retval->write = physfsrwops_write;
       
   179             retval->close = physfsrwops_close;
       
   180             retval->hidden.unknown.data1 = handle;
       
   181         } /* if */
       
   182     } /* else */
       
   183 
       
   184     return retval;
       
   185 } /* create_rwops */
       
   186 
       
   187 
       
   188 SDL_RWops *PHYSFSRWOPS_makeRWops(PHYSFS_File *handle)
       
   189 {
       
   190     SDL_RWops *retval = NULL;
       
   191     if (handle == NULL)
       
   192         SDL_SetError("NULL pointer passed to PHYSFSRWOPS_makeRWops().");
       
   193     else
       
   194         retval = create_rwops(handle);
       
   195 
       
   196     return retval;
       
   197 } /* PHYSFSRWOPS_makeRWops */
       
   198 
       
   199 
       
   200 SDL_RWops *PHYSFSRWOPS_openRead(const char *fname)
       
   201 {
       
   202     return create_rwops(PHYSFS_openRead(fname));
       
   203 } /* PHYSFSRWOPS_openRead */
       
   204 
       
   205 
       
   206 SDL_RWops *PHYSFSRWOPS_openWrite(const char *fname)
       
   207 {
       
   208     return create_rwops(PHYSFS_openWrite(fname));
       
   209 } /* PHYSFSRWOPS_openWrite */
       
   210 
       
   211 
       
   212 SDL_RWops *PHYSFSRWOPS_openAppend(const char *fname)
       
   213 {
       
   214     return create_rwops(PHYSFS_openAppend(fname));
       
   215 } /* PHYSFSRWOPS_openAppend */
       
   216 
       
   217 
       
   218 /* end of physfsrwops.c ... */
       
   219