X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/rsbs2/blobdiff_plain/6b2c0993a746ebda6ae633e75a8a82533c50b506..c9427cf83b4389d0a3f03844c55ae990d5bec6f3:/rsb-lz.c?ds=inline

diff --git a/rsb-lz.c b/rsb-lz.c
index 7d20942..bb735d6 100644
--- a/rsb-lz.c
+++ b/rsb-lz.c
@@ -15,10 +15,10 @@ void err_exit(const char *fname)
 }
 
 struct data_in_s {
-	unsigned char *start; /* 0 */
-	unsigned char *stop; /* 4 */
-	unsigned char bit; /* 8 */
-	unsigned char x; /* 9 */
+	unsigned char *start;
+	unsigned char *stop;
+	unsigned char bitpos;
+	unsigned char byte;
 };
 
 struct data_out_s {
@@ -39,167 +39,240 @@ unsigned char get_next_in_byte(struct data_in_s *data_in)
 	return byte;
 }
 
-unsigned int fn_59848(struct data_in_s *data_in)
+unsigned char get_next_bit(struct data_in_s *data_in)
 {
-	unsigned int r5;
+	unsigned char bitval;
 
-	if (data_in->bit == 0x80) {
-		data_in->x = get_next_in_byte(data_in);
+	if (data_in->bitpos == 0x80) {
+		data_in->byte = get_next_in_byte(data_in);
 	}
 
-	r5 = data_in->bit & data_in->x & 0xff;
+	bitval = data_in->bitpos & data_in->byte;
 
-	data_in->bit >>= 1;
-	if (data_in->bit == 0) {
-		data_in->bit = 0x80;
+	data_in->bitpos >>= 1;
+	if (data_in->bitpos == 0) {
+		data_in->bitpos = 0x80;
 	}
 
-	if (r5 == 0)
+	if (bitval == 0)
 		return 0;
 
 	return 1;
 }
 
-unsigned int fn_598b4(struct data_in_s *r11_data, unsigned int r10_arg2)
+unsigned int get_next_bits(struct data_in_s *data_in, unsigned int bits)
 {
-	unsigned int r1;
-	unsigned int r2;
-	unsigned int r6;
-	unsigned int r7;
-
-	r1 = r10_arg2 - 1;
-	r6 = 1 << r1;
-
-	r7 = 0;
-	while (r6 != 0) {
-		r1 = r11_data->bit;
-		if (r1 == 0x80) {
-			r1 = get_next_in_byte(r11_data);
-			r11_data->x = r1;
+	unsigned int bit;
+	unsigned int next_bits;
+
+	bit = 1 << (bits - 1);
+
+	next_bits = 0;
+	while (bit != 0) {
+		if (data_in->bitpos == 0x80) {
+			data_in->byte = get_next_in_byte(data_in);
 		}
-		r1 = r11_data->bit;
-		r2 = r11_data->x;
-		r1 = r1 & r2;
-		if (r1 != 0)
-			r7 = r7 | r6;
 
-		r6 = r6 >> 1;
+		if ((data_in->bitpos & data_in->byte) != 0)
+			next_bits = next_bits | bit;
 
-		r2 = r11_data->bit;
-		r2 = r2 >> 1;
-		r11_data->bit = r2;
+		bit = bit >> 1;
 
-		r1 = r11_data->bit;
-		if(r1 == 0) {
-			r11_data->bit = 0x80;
+		data_in->bitpos >>= 1;
+
+		if(data_in->bitpos == 0) {
+			data_in->bitpos = 0x80;
 		}
 	}
 
-	return r7;
+	return next_bits;
 }
 
-void fn_5980c(unsigned int arg1, struct data_out_s *data_out)
+void write_byte(unsigned char byte, struct data_out_s *data_out)
 {
-	unsigned char *r1;
-	unsigned char *r2;
-
-	r1 = data_out->pos;
-	r2 = data_out->end;
-
-	if (r1 > r2) {
-		printf("r1: 0x%08x, r2: 0x%08x\n", (unsigned int)r1, (unsigned int)r2);
+	if (data_out->pos > data_out->end) {
 		err_exit(__func__);
 	}
 
-	*r1 = arg1 & 0xff;
-
-	r1++;
-	data_out->pos = r1;
+	*(data_out->pos) = byte;
+	data_out->pos++;
 }
 
-void lz_expand(struct data_in_s *r10_data, struct data_out_s *data_out)
+void lz_expand(struct data_in_s *data_in, struct data_out_s *data_out)
 {
-	unsigned int r5;
-	unsigned int r2;
-	unsigned char r4;
-	unsigned int r6;
-	unsigned int r7;
-	unsigned int r11;
-	unsigned char arr_59b64[1024];
+	unsigned int pos;
+	unsigned int wordoffset;
+	unsigned int i;
+	unsigned char byte;
+	unsigned int wordlen;
+	unsigned char buf[1024];
 
-	r5 = 1;
+	pos = 1;
 
 	while (1) {
 		while (1) {
-			r2 = fn_59848(r10_data);
-			if (r2 == 0)
+			/* Compressed/uncompressed? */
+			if (get_next_bit(data_in) == 0)
 				break;
 
-			r2 = fn_598b4(r10_data, 8) & 0xff;
+			/* Uncompressed byte */
+			byte = get_next_bits(data_in, 8);
+
+			write_byte(byte, data_out);
 
-			fn_5980c(r2, data_out);
-			arr_59b64[r5] = r2 & 0xff;
-			r5 = (r5 + 1) & 0x3ff;
+			/* Save byte in buffer, to be reused later */
+			buf[pos] = byte;
+			pos = (pos + 1) & 0x3ff;
 		}
 
-		r11 = fn_598b4(r10_data, 0x0a);
-		if(r11 == 0)
+		/* offset for start of dictionary word */
+		wordoffset = get_next_bits(data_in, 0x0a);
+		if(wordoffset == 0)
 			return;
 
-		r2 = fn_598b4(r10_data, 0x04);
-		r7 = r2 + 1;
-		r6 = 0;
-		while (r6 <= r7) {
-			r2 = (r6 + r11) & 0x3ff;
-			r4 = arr_59b64[r2];
-			fn_5980c(r4, data_out);
-			arr_59b64[r5] = r4;
-			r5 = (r5 + 1) & 0x3ff;
-			r6++;
+		/* length of dictionary word used */
+		wordlen = get_next_bits(data_in, 0x04) + 1;
+		for (i = 0; i <= wordlen ; i++) {
+			/* lookup dictionary byte */
+			byte = buf[(wordoffset + i) & 0x3ff];
+			write_byte(byte, data_out);
+			/* Save byte in buffer, to be reused later */
+			buf[pos] = byte;
+			pos = (pos + 1) & 0x3ff;
 		}
 	}
 }
 
-/* Checksum is only used for the compressed firmware in 'firmware' */
-#if 0
-unsigned int crc_check_59684(unsigned char *arg1, unsigned int arg2, unsigned int magic)
+void set_next_bit(unsigned char *buf, unsigned int set, unsigned int *currbit) {
+	unsigned char *pos;
+	unsigned char bitpos;
+
+	if (set) {
+		pos = buf + ((*currbit) / 8);
+		bitpos = 0x80 >> ((*currbit) % 8);
+		*pos |= bitpos;
+	}
+
+	*currbit = *currbit + 1;
+}
+
+void write_bits(unsigned char *buf, unsigned int data, unsigned int bits, unsigned int *currbit) {
+	int i;
+	unsigned int bitpos;
+
+	bitpos = 1 << (bits - 1);
+
+	for (i = 0; i < bits; i++) {
+		set_next_bit(buf, data & bitpos, currbit);
+		bitpos >>= 1;
+	}
+}
+
+unsigned char *compress_lz(unsigned char *inbuf, int inlen, int *outlen)
 {
-	unsigned int r3;
-	unsigned int r4;
-	unsigned int r5;
+	unsigned char *end = inbuf + inlen;
+	unsigned char *outbuf;
+	unsigned char window[1024];
+	int pos = 0;
+	int fill = 0;
+	unsigned int currbit = 0;
+	int offset;
+	int wordlen;
+	int found;
+	int i;
+
+	if ((outbuf = malloc((inlen * 2) + 4)) == NULL) {
+		perror("malloc");
+	}
+
+	*((unsigned int*)outbuf) = LZ_MAGIC;
+	currbit = 8 * 8;
+
+	while(inbuf < end) {
+		found = 0;
+		for (wordlen = 17; wordlen > 1; wordlen--) {
+			for (offset = 1; offset < ((fill < 1023) ? fill : 1023); offset++) {
+				if ((fill < 1023) &&
+				    (wordlen + offset > fill))
+					break;
+
+				for (i = 0; i < wordlen; i++) {
+					if (inbuf[i] != window[(offset + i) & 0x3ff]) {
+						break;
+					}
+				}
+				if (i == wordlen)
+					found = 1;
+			}
+			if (found)
+				break;
+		}
+
+		if (found) {
+			write_bits(outbuf, 0x00, 0x01, &currbit);
+			write_bits(outbuf, offset, 0x0a, &currbit);
+			write_bits(outbuf, wordlen - 1, 0x04, &currbit);
+			for (i = 0; i < wordlen; i++) {
+				window[pos] = *(inbuf + i);
+				pos = (pos + 1) & 0x3ff;
+			}
+			inbuf += wordlen;
+
+			if (fill < sizeof(window))
+				fill += wordlen;
+		} else {
+			write_bits(outbuf, 0x01, 0x01, &currbit);
+			write_bits(outbuf, *inbuf, 0x08, &currbit);
+			window[pos] = *inbuf;
+			pos = (pos + 1) & 0x3ff;
+			inbuf++;
+			if (fill < sizeof(window))
+				fill++;
+		}
+	}
+
+	write_bits(outbuf, 0x00, 0x01, &currbit);
+	write_bits(outbuf, 0x00, 0x0a, &currbit);
+
+	*outlen = (currbit / 8) + 1;
+
+	*((unsigned int*)(outbuf + 4)) = *outlen;
 
-#if 0
-	if (r0 < 0xc0000000)
-		return 1;
-#endif
+	return outbuf;
+}
+
+/* Checksum is only used for the compressed firmware in 'firmware' */
+unsigned int crc_check(unsigned char *buf, unsigned int len, unsigned int magic)
+{
+	unsigned int file_crc;
+	unsigned int my_len;
+	unsigned int crc;
+	unsigned int my_magic;
 
-	/* ??? */
-	r4 = *((unsigned int*)arg1 + 0x20);
-	r5 = *((unsigned int*)arg1 + 0x24);
+	my_len = *((unsigned int*)(buf + 0x20));
+	my_magic = *((unsigned int*)(buf + 0x24));
 
-	printf("magic: 0x%08x <-> 0x%08x\n", r5, magic);
-	if (r5 != magic)
+	if (my_magic != magic) {
+		printf("\nmagic: 0x%08x <-> 0x%08x\n", my_magic, magic);
 		return 2;
+	}
 	
-	if (arg2 >= r4)
-		r5 = 0;
-	else
+	if (len < my_len)
 		return 3;
 
-	r5 = ~rsb_crc(~0x00, arg1, r4);
-	r3 = *((unsigned int*)(arg1 + r4));
-	printf("Checksums: 0x%02x <-> 0x%02x\n", r5, r3);
+	crc = ~rsb_crc(~0x00, buf, len);
+	file_crc = *((unsigned int*)(buf + len));
 
-	if (r3 == r5)
-		return 0;
+	if (file_crc != crc) {
+		printf("\nChecksums: 0x%08x <-> 0x%08x!\n", crc, file_crc);
+		return 4;
+	}
 
-	return 4;
+	return 0;
 }
-#endif
 
-void extract_lz_file(unsigned char *inbuf, unsigned char *name)
+unsigned char *extract_lz_file(unsigned char *inbuf, unsigned int *outlen , unsigned char check_crc)
 {
-	unsigned int len;
 	unsigned char *outbuf;
 	struct data_in_s data_in;
 	struct data_out_s data_out;
@@ -207,38 +280,37 @@ void extract_lz_file(unsigned char *inbuf, unsigned char *name)
 	if (*((unsigned int*)inbuf) != LZ_MAGIC)
 		err_exit(__func__);
 
-	len = *((unsigned int*)(inbuf + 4));
-	printf(", length: %d", len);
+	*outlen = *((unsigned int*)(inbuf + 4));
+	printf(", length: %d", *outlen);
 
-	if ((outbuf = malloc(len)) == NULL) {
+	if ((outbuf = malloc(*outlen)) == NULL) {
 		perror("malloc");
 		exit(1);
 	}
 
-	bzero(outbuf, len);
+	bzero(outbuf, *outlen);
 
 	data_in.start = inbuf + 8;
-	data_in.stop = inbuf + len;
-	data_in.x = 0;
-	data_in.bit = 0x80;
+	data_in.stop = inbuf + *outlen;
+	data_in.byte = 0x00;
+	data_in.bitpos = 0x80;
 
 	data_out.pos = outbuf;
-	data_out.end = outbuf + len;
+	data_out.end = outbuf + *outlen;
 
 	lz_expand(&data_in, &data_out);
 
-#if 0
-	/* Checksum is only used for the compressed firmware in 'firmware' */
-	r3 = r7 + 0x20;
-	r5 = *((unsigned int*)r3);
+	if (check_crc) {
+		unsigned int crclen;
+		int ret;
 
-	if ((ret = crc_check_59684(r7, r5, 0x46335053)) != 0) {
-		printf("crc_check return: %d\n", ret);
-		err_exit(__func__);
+		crclen = *((unsigned int*)(outbuf + 0x20));
+
+		if ((ret = crc_check(outbuf, crclen, 0x46335053)) != 0) {
+			printf("crc_check return: %d\n", ret);
+			err_exit(__func__);
+		}
 	}
-#endif
 
-	write_file((char*)name, outbuf, len);
-	
-	free(outbuf);
+	return outbuf;
 }