1 /*

     2  * MVL support routines for PhysicsFS.

     3  *

     4  * This driver handles Descent II Movielib archives.

     5  *

     6  * The file format of MVL is quite easy...

     7  *

     8  *   //MVL File format - Written by Heiko Herrmann

     9  *   char sig[4] = {'D','M', 'V', 'L'}; // "DMVL"=Descent MoVie Library

    10  *

    11  *   int num_files; // the number of files in this MVL

    12  *

    13  *   struct {

    14  *    char file_name[13]; // Filename, padded to 13 bytes with 0s

    15  *    int file_size; // filesize in bytes

    16  *   }DIR_STRUCT[num_files];

    17  *

    18  *   struct {

    19  *    char data[file_size]; // The file data

    20  *   }FILE_STRUCT[num_files];

    21  *

    22  * (That info is from http://www.descent2.com/ddn/specs/mvl/)

    23  *

    24  * Please see the file LICENSE.txt in the source's root directory.

    25  *

    26  *  This file written by Bradley Bell.

    27  *  Based on grp.c by Ryan C. Gordon.

    28  */

    29 

    30 #define __PHYSICSFS_INTERNAL__

    31 #include "physfs_internal.h"

    32 

    33 #if PHYSFS_SUPPORTS_MVL

    34 

    35 static UNPKentry *mvlLoadEntries(PHYSFS_Io *io, PHYSFS_uint32 fileCount)

    36 {

    37     PHYSFS_uint32 location = 8;  /* sizeof sig. */

    38     UNPKentry *entries = NULL;

    39     UNPKentry *entry = NULL;

    40 

    41     entries = (UNPKentry *) allocator.Malloc(sizeof (UNPKentry) * fileCount);

    42     BAIL_IF_MACRO(entries == NULL, PHYSFS_ERR_OUT_OF_MEMORY, NULL);

    43 

    44     location += (17 * fileCount);

    45 

    46     for (entry = entries; fileCount > 0; fileCount--, entry++)

    47     {

    48         if (!__PHYSFS_readAll(io, &entry->name, 13)) goto failed;

    49         if (!__PHYSFS_readAll(io, &entry->size, 4)) goto failed;

    50         entry->size = PHYSFS_swapULE32(entry->size);

    51         entry->startPos = location;

    52         location += entry->size;

    53     } /* for */

    54 

    55     return entries;

    56 

    57 failed:

    58     allocator.Free(entries);

    59     return NULL;

    60 } /* mvlLoadEntries */

    61 

    62 

    63 static void *MVL_openArchive(PHYSFS_Io *io, const char *name, int forWriting)

    64 {

    65     PHYSFS_uint8 buf[4];

    66     PHYSFS_uint32 count = 0;

    67     UNPKentry *entries = NULL;

    68 

    69     assert(io != NULL);  /* shouldn't ever happen. */

    70     BAIL_IF_MACRO(forWriting, PHYSFS_ERR_READ_ONLY, NULL);

    71     BAIL_IF_MACRO(!__PHYSFS_readAll(io, buf, 4), ERRPASS, NULL);

    72     BAIL_IF_MACRO(memcmp(buf, "DMVL", 4) != 0, PHYSFS_ERR_UNSUPPORTED, NULL);

    73     BAIL_IF_MACRO(!__PHYSFS_readAll(io, &count, sizeof(count)), ERRPASS, NULL);

    74 

    75     count = PHYSFS_swapULE32(count);

    76     entries = mvlLoadEntries(io, count);

    77     return (!entries) ? NULL : UNPK_openArchive(io, entries, count);

    78 } /* MVL_openArchive */

    79 

    80 

    81 const PHYSFS_Archiver __PHYSFS_Archiver_MVL =

    82 {

    83     CURRENT_PHYSFS_ARCHIVER_API_VERSION,

    84     {

    85         "MVL",

    86         "Descent II Movielib format",

    87         "Bradley Bell <btb@icculus.org>",

    88         "https://icculus.org/physfs/",

    89         0,  /* supportsSymlinks */

    90     },

    91     MVL_openArchive,

    92     UNPK_enumerateFiles,

    93     UNPK_openRead,

    94     UNPK_openWrite,

    95     UNPK_openAppend,

    96     UNPK_remove,

    97     UNPK_mkdir,

    98     UNPK_stat,

    99     UNPK_closeArchive

   100 };

   101 

   102 #endif  /* defined PHYSFS_SUPPORTS_MVL */

   103 

   104 /* end of archiver_mvl.c ... */

   105