Wow I forgot I have stuff here that wasn't added.

iwad64ex.c

@@ -0,0 +1,128 @@
+/*
+	iwad64ex.c : Extracts the embedded IWAD in Hexen 64.
+	Currently does not decompress the data (or fix the endianness in data).
+	(C)2019 Marisa Kirisame, UnSX Team.
+	Released under the GNU General Public License version 3.
+*/
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <errno.h>
+
+typedef struct
+{
+	char sig[4];
+	uint32_t nlumps;
+	uint32_t dirpos;
+} wad_t;
+
+typedef struct
+{
+	uint32_t filepos, size;
+	char name[8];
+} lump_t;
+
+char *data;
+wad_t *wad;
+lump_t *lumps;
+
+uint32_t btl( uint32_t b )
+{
+	return ((b>>24)&0xff)|((b<<8)&0xff0000)
+		|((b>>8)&0xff00)|((b<<24)&0xff000000);
+}
+
+int main( int argc, char **argv )
+{
+	if ( argc < 3 )
+	{
+		fprintf(stderr,"usage: iwad64ex <romfile> <wadfile>\n");
+		return 1;
+	}
+	FILE *romfile = fopen(argv[1],"rb");
+	if ( !romfile )
+	{
+		fprintf(stderr,"failed to open %s for reading: %s\n",
+			argv[1],strerror(errno));
+		return 2;
+	}
+	ssize_t fpos = 0;
+	char buf[4096];
+	ssize_t found = 0;
+	while ( !feof(romfile) )
+	{
+		memset(buf,0,4096);
+		int bsiz = fread(buf,1,4096,romfile);
+		// to avoid GNU-exclusive memmem function I'll just roll out
+		// my own thing here (fuckin' GNU and their exclusives...)
+		for ( int i=0; i<bsiz-5; i++ )
+		{
+			if ( !memcmp(buf+i,"IWAD",4)
+				|| !memcmp(buf+i,"PWAD",4) )
+			{
+				fpos += i;
+				found = 1;
+				break;
+			}
+		}
+		if ( found ) break;
+		fpos += bsiz;
+	}
+	if ( !found )
+	{
+		fclose(romfile);
+		fprintf(stderr,"WAD signature not found in ROM\n");
+		return 8;
+	}
+	printf("Embedded wad found at %#zx\n",fpos);
+	data = malloc(12);
+	if ( !data )
+	{
+		fclose(romfile);
+		fprintf(stderr,"cannot allocate 12 bytes for wad header: %s",
+			strerror(errno));
+		return 16;
+	}
+	fseek(romfile,fpos,SEEK_SET);
+	fread(data,1,12,romfile);
+	wad = (wad_t*)data;
+	// fix endianness
+	wad->nlumps = btl(wad->nlumps);
+	wad->dirpos = btl(wad->dirpos);
+	// reallocate to fit
+	size_t fullsiz = wad->dirpos+wad->nlumps*16;
+	data = realloc(data,fullsiz);
+	wad = (wad_t*)data;
+	if ( errno )
+	{
+		fclose(romfile);
+		free(data);
+		fprintf(stderr,"cannot allocate %zd bytes for full wad: %s",
+			fullsiz,strerror(errno));
+		return 32;
+	}
+	fread(data+12,1,fullsiz-12,romfile);
+	lumps = (lump_t*)(data+wad->dirpos);
+	// loop and fix endianness
+	for ( int i=0; i<wad->nlumps; i++ )
+	{
+		lumps[i].filepos = btl(lumps[i].filepos);
+		lumps[i].size = btl(lumps[i].size);
+		printf("%.8s %d %d\n",lumps[i].name,lumps[i].size,
+			lumps[i].filepos);
+	}
+	fclose(romfile);
+	FILE *wadfile = fopen(argv[2],"wb");
+	if ( !wadfile )
+	{
+		fprintf(stderr,"failed to open %s for writing: %s\n",
+			argv[2],strerror(errno));
+		return 4;
+	}
+	fwrite(data,1,fullsiz,wadfile);
+	fclose(wadfile);
+	free(data);
+	printf("wrote %s, %d bytes\n",argv[2],fullsiz);
+	return 0;
+}