misc/physfs/src/archiver_wad.c
branchphysfslayer
changeset 7768 13e2037ebc79
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/misc/physfs/src/archiver_wad.c	Sat Oct 20 00:20:39 2012 +0400
@@ -0,0 +1,127 @@
+/*
+ * WAD support routines for PhysicsFS.
+ *
+ * This driver handles DOOM engine archives ("wads"). 
+ * This format (but not this driver) was designed by id Software for use
+ *  with the DOOM engine.
+ * The specs of the format are from the unofficial doom specs v1.666
+ * found here: http://www.gamers.org/dhs/helpdocs/dmsp1666.html
+ * The format of the archive: (from the specs)
+ *
+ *  A WAD file has three parts:
+ *  (1) a twelve-byte header
+ *  (2) one or more "lumps"
+ *  (3) a directory or "info table" that contains the names, offsets, and
+ *      sizes of all the lumps in the WAD
+ *
+ *  The header consists of three four-byte parts:
+ *    (a) an ASCII string which must be either "IWAD" or "PWAD"
+ *    (b) a 4-byte (long) integer which is the number of lumps in the wad
+ *    (c) a long integer which is the file offset to the start of
+ *    the directory
+ *
+ *  The directory has one 16-byte entry for every lump. Each entry consists
+ *  of three parts:
+ *
+ *    (a) a long integer, the file offset to the start of the lump
+ *    (b) a long integer, the size of the lump in bytes
+ *    (c) an 8-byte ASCII string, the name of the lump, padded with zeros.
+ *        For example, the "DEMO1" entry in hexadecimal would be
+ *        (44 45 4D 4F 31 00 00 00)
+ * 
+ * Note that there is no way to tell if an opened WAD archive is a
+ *  IWAD or PWAD with this archiver.
+ * I couldn't think of a way to provide that information, without being too
+ *  hacky.
+ * I don't think it's really that important though.
+ *
+ *
+ * Please see the file LICENSE.txt in the source's root directory.
+ *
+ * This file written by Travis Wells, based on the GRP archiver by
+ *  Ryan C. Gordon.
+ */
+
+#define __PHYSICSFS_INTERNAL__
+#include "physfs_internal.h"
+
+#if PHYSFS_SUPPORTS_WAD
+
+static UNPKentry *wadLoadEntries(PHYSFS_Io *io, PHYSFS_uint32 fileCount)
+{
+    PHYSFS_uint32 directoryOffset;
+    UNPKentry *entries = NULL;
+    UNPKentry *entry = NULL;
+
+    BAIL_IF_MACRO(!__PHYSFS_readAll(io, &directoryOffset, 4), ERRPASS, 0);
+    directoryOffset = PHYSFS_swapULE32(directoryOffset);
+
+    BAIL_IF_MACRO(!io->seek(io, directoryOffset), ERRPASS, 0);
+
+    entries = (UNPKentry *) allocator.Malloc(sizeof (UNPKentry) * fileCount);
+    BAIL_IF_MACRO(!entries, PHYSFS_ERR_OUT_OF_MEMORY, NULL);
+
+    for (entry = entries; fileCount > 0; fileCount--, entry++)
+    {
+        if (!__PHYSFS_readAll(io, &entry->startPos, 4)) goto failed;
+        if (!__PHYSFS_readAll(io, &entry->size, 4)) goto failed;
+        if (!__PHYSFS_readAll(io, &entry->name, 8)) goto failed;
+
+        entry->name[8] = '\0'; /* name might not be null-terminated in file. */
+        entry->size = PHYSFS_swapULE32(entry->size);
+        entry->startPos = PHYSFS_swapULE32(entry->startPos);
+    } /* for */
+
+    return entries;
+
+failed:
+    allocator.Free(entries);
+    return NULL;
+} /* wadLoadEntries */
+
+
+static void *WAD_openArchive(PHYSFS_Io *io, const char *name, int forWriting)
+{
+    PHYSFS_uint8 buf[4];
+    UNPKentry *entries = NULL;
+    PHYSFS_uint32 count = 0;
+
+    assert(io != NULL);  /* shouldn't ever happen. */
+
+    BAIL_IF_MACRO(forWriting, PHYSFS_ERR_READ_ONLY, NULL);
+    BAIL_IF_MACRO(!__PHYSFS_readAll(io, buf, sizeof (buf)), ERRPASS, NULL);
+    if ((memcmp(buf, "IWAD", 4) != 0) && (memcmp(buf, "PWAD", 4) != 0))
+        BAIL_MACRO(PHYSFS_ERR_UNSUPPORTED, NULL);
+
+    BAIL_IF_MACRO(!__PHYSFS_readAll(io, &count, sizeof (count)), ERRPASS, NULL);
+    count = PHYSFS_swapULE32(count);
+
+    entries = wadLoadEntries(io, count);
+    BAIL_IF_MACRO(!entries, ERRPASS, NULL);
+    return UNPK_openArchive(io, entries, count);
+} /* WAD_openArchive */
+
+
+const PHYSFS_Archiver __PHYSFS_Archiver_WAD =
+{
+    {
+        "WAD",
+        "DOOM engine format",
+        "Travis Wells <traviswells@mchsi.com>",
+        "http://www.3dmm2.com/doom/",
+    },
+    WAD_openArchive,        /* openArchive() method    */
+    UNPK_enumerateFiles,     /* enumerateFiles() method */
+    UNPK_openRead,           /* openRead() method       */
+    UNPK_openWrite,          /* openWrite() method      */
+    UNPK_openAppend,         /* openAppend() method     */
+    UNPK_remove,             /* remove() method         */
+    UNPK_mkdir,              /* mkdir() method          */
+    UNPK_closeArchive,       /* closeArchive() method   */
+    UNPK_stat                /* stat() method           */
+};
+
+#endif  /* defined PHYSFS_SUPPORTS_WAD */
+
+/* end of wad.c ... */
+