From f5086e0845b6421e782ccebb9fa1f6382cb01987 Mon Sep 17 00:00:00 2001
From: Vladimir Serbinenko <phcoder@gmail.com>
Date: Mon, 13 Mar 2023 20:38:09 +0100
Subject: [PATCH] SCUMM: Add a tool for extracting nd4 archive as used by
 floppy version of indy4

---
 Makefile.common               |   6 ++
 engines/scumm/extract_lfg.cpp | 114 ++++++++++++++++++++++++++++++++++
 2 files changed, 120 insertions(+)
 create mode 100644 engines/scumm/extract_lfg.cpp

diff --git a/Makefile.common b/Makefile.common
index af5e53d7..1ec1a5ac 100644
--- a/Makefile.common
+++ b/Makefile.common
@@ -41,6 +41,7 @@ PROGRAMS = \
 	extract_hadesch_img \
 	extract_lokalizator \
 	extract_mps \
+	extract_lfg \
 	grim_animb2txt \
 	grim_bm2bmp \
 	grim_cosb2cos \
@@ -160,6 +161,11 @@ extract_mps_OBJS := \
 	common/dcl.o \
 	$(UTILS)
 
+extract_lfg_OBJS := \
+	engines/scumm/extract_lfg.o \
+	common/dcl.o \
+	$(UTILS)
+
 deprince_OBJS := \
 	engines/prince/deprince.o \
 	engines/prince/flags.o \
diff --git a/engines/scumm/extract_lfg.cpp b/engines/scumm/extract_lfg.cpp
new file mode 100644
index 00000000..8bd86196
--- /dev/null
+++ b/engines/scumm/extract_lfg.cpp
@@ -0,0 +1,114 @@
+/* ScummVM Tools
+ *
+ * ScummVM Tools is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "common/endian.h"
+#include "common/memstream.h"
+#include "common/file.h"
+#include "common/str.h"
+#include "common/util.h"
+#include "common/dcl.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+int main (int argc, char **argv) {
+	unsigned char *buf = nullptr;
+	size_t inSize = 0;
+
+	if (argc < 3) {
+		fprintf (stderr, "USAGE: %s OUTDIR VOLUMES\n", argv[0]);
+		return -1;
+	}
+
+	for (int i = 2; i < argc; i++) {
+		FILE *fin = fopen (argv[i], "rb");
+		byte head[8];
+		if (fin == NULL) {
+			fprintf (stderr, "Unable to open %s: %s\n", argv[i], strerror(errno));
+			free (buf);
+			return -2;
+		}
+		fread (head, 1, 8, fin);
+		if (READ_BE_UINT32(head) != MKTAG('L', 'F', 'G', '!')) {
+			fprintf (stderr, "%s doesn't contain magic\n", argv[i]);
+			free (buf);
+			return -2;			
+		}
+		uint32 volumeSize = READ_LE_UINT32(head + 4);
+		uint32 oldInSize = inSize;
+		inSize += volumeSize;
+
+		buf = (byte *) realloc (buf, inSize);
+		fread (buf + oldInSize, 1, volumeSize, fin);
+		fclose (fin);
+	}
+
+	printf("Archive name: %s\n", buf);
+	printf("Value A=0x%x\n", buf[13]);
+	printf("Value B=0x%x\n", READ_LE_UINT16(buf+14));
+	printf("Total number of bytes=0x%x\n", READ_LE_UINT32(buf+16));
+
+	for (byte *ptr = buf + 0x14; ptr < buf + inSize;) {
+		uint32 magic = READ_BE_UINT32(ptr);
+		if (magic != MKTAG('F', 'I', 'L', 'E')) {
+			printf("Wrong magic: %x @ %x\n", magic, (int)(ptr - buf));
+			free (buf);
+			return 0;
+		}
+		uint32 blocklen = READ_LE_UINT32(ptr + 4);
+		byte *blockend = ptr + 8 + blocklen;
+		ptr += 8;
+		Common::String name((char *)ptr, 13);
+		ptr += 13;
+		Common::File fout(Common::String::format("%s/%s", argv[1], name.c_str()), "wb");
+		uint32 uncompressedSize = READ_LE_UINT32(ptr + 1);
+		printf("name: %s\n", name.c_str());
+		printf("value C=0x%x\n", ptr[0]);
+		// ptr[0] is always 0x17 or 0x19 so far
+		// ptr + 5 is always 02 00 01 00 00 00 so far
+		printf("value D:\n");
+		hexdump(ptr + 5, 6);
+		// Most likely it contains compression somewhere
+		ptr += 11;
+
+		uint32 compressedSize = blockend - ptr;
+		byte *uncompressedBuf = nullptr;
+
+		// DCL. TODO: Support uncompressed if needed
+		Common::MemoryReadStream compressedReadStream(ptr, compressedSize);
+		uncompressedBuf = new byte[uncompressedSize];
+		if (!Common::decompressDCL(&compressedReadStream, uncompressedBuf, compressedSize, uncompressedSize)) {
+			fprintf (stderr, "Unable to decompress %s\n", name.c_str());
+			delete[] uncompressedBuf;
+			continue;
+		}
+		
+		fout.write(uncompressedBuf, uncompressedSize);
+		ptr = blockend;
+
+		delete[] uncompressedBuf;
+	}
+
+	free (buf);
+
+	return 0;
+}