X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=blobdiff_plain;ds=sidebyside;f=deps%2Flibchdr%2Fhuffman.c;h=a58b6be8248659b8ff32a0b2eac37f4de29e5fa8;hb=e3e1b865f7c06f57918b97f7293b5b2959fb7b7d;hp=f48210ea510c4ce19a445057286ebf5ff2183092;hpb=a34093eb63d1645fd2de9b412efe2587df9fdb3f;p=pcsx_rearmed.git

diff --git a/deps/libchdr/huffman.c b/deps/libchdr/huffman.c
index f48210ea..a58b6be8 100644
--- a/deps/libchdr/huffman.c
+++ b/deps/libchdr/huffman.c
@@ -125,11 +125,13 @@
 
 struct huffman_decoder* create_huffman_decoder(int numcodes, int maxbits)
 {
+	struct huffman_decoder* decoder = NULL;
+
 	/* limit to 24 bits */
 	if (maxbits > 24)
 		return NULL;
 
-	struct huffman_decoder* decoder = (struct huffman_decoder*)malloc(sizeof(struct huffman_decoder));
+	decoder = (struct huffman_decoder*)malloc(sizeof(struct huffman_decoder));
 	decoder->numcodes = numcodes;
 	decoder->maxbits = maxbits;
 	decoder->lookup = (lookup_value*)malloc(sizeof(lookup_value) * (1 << maxbits));
@@ -167,8 +169,10 @@ uint32_t huffman_decode_one(struct huffman_decoder* decoder, struct bitstream* b
 
 enum huffman_error huffman_import_tree_rle(struct huffman_decoder* decoder, struct bitstream* bitbuf)
 {
+	int numbits, curnode;
+	enum huffman_error error;
+
 	/* bits per entry depends on the maxbits */
-	int numbits;
 	if (decoder->maxbits >= 16)
 		numbits = 5;
 	else if (decoder->maxbits >= 8)
@@ -177,7 +181,6 @@ enum huffman_error huffman_import_tree_rle(struct huffman_decoder* decoder, stru
 		numbits = 3;
 
 	/* loop until we read all the nodes */
-	int curnode;
 	for (curnode = 0; curnode < decoder->numcodes; )
 	{
 		/* a non-one value is just raw */
@@ -208,7 +211,7 @@ enum huffman_error huffman_import_tree_rle(struct huffman_decoder* decoder, stru
 		return HUFFERR_INVALID_DATA;
 
 	/* assign canonical codes for all nodes based on their code lengths */
-	enum huffman_error error = huffman_assign_canonical_codes(decoder);
+	error = huffman_assign_canonical_codes(decoder);
 	if (error != HUFFERR_NONE)
 		return error;
 
@@ -228,12 +231,19 @@ enum huffman_error huffman_import_tree_rle(struct huffman_decoder* decoder, stru
 
 enum huffman_error huffman_import_tree_huffman(struct huffman_decoder* decoder, struct bitstream* bitbuf)
 {
+	int start;
+	int last = 0;
+	int count = 0;
+	int index;
+	int curcode;
+	uint8_t rlefullbits = 0;
+	uint32_t temp;
+	enum huffman_error error;
 	/* start by parsing the lengths for the small tree */
 	struct huffman_decoder* smallhuff = create_huffman_decoder(24, 6);
 	smallhuff->huffnode[0].numbits = bitstream_read(bitbuf, 3);
-	int start = bitstream_read(bitbuf, 3) + 1;
-	int count = 0;
-	for (int index = 1; index < 24; index++)
+	start = bitstream_read(bitbuf, 3) + 1;
+	for (index = 1; index < 24; index++)
 	{
 		if (index < start || count == 7)
 			smallhuff->huffnode[index].numbits = 0;
@@ -245,20 +255,17 @@ enum huffman_error huffman_import_tree_huffman(struct huffman_decoder* decoder,
 	}
 
 	/* then regenerate the tree */
-	enum huffman_error error = huffman_assign_canonical_codes(smallhuff);
+	error = huffman_assign_canonical_codes(smallhuff);
 	if (error != HUFFERR_NONE)
 		return error;
 	huffman_build_lookup_table(smallhuff);
 
 	/* determine the maximum length of an RLE count */
-	uint32_t temp = decoder->numcodes - 9;
-	uint8_t rlefullbits = 0;
+	temp = decoder->numcodes - 9;
 	while (temp != 0)
 		temp >>= 1, rlefullbits++;
 
 	/* now process the rest of the data */
-	int last = 0;
-	int curcode;
 	for (curcode = 0; curcode < decoder->numcodes; )
 	{
 		int value = huffman_decode_one(smallhuff, bitbuf);
@@ -298,14 +305,17 @@ enum huffman_error huffman_import_tree_huffman(struct huffman_decoder* decoder,
 
 enum huffman_error huffman_compute_tree_from_histo(struct huffman_decoder* decoder)
 {
+	int i;
+	uint32_t lowerweight;
+	uint32_t upperweight;
 	/* compute the number of data items in the histogram */
 	uint32_t sdatacount = 0;
-	for (int i = 0; i < decoder->numcodes; i++)
+	for (i = 0; i < decoder->numcodes; i++)
 		sdatacount += decoder->datahisto[i];
 
 	/* binary search to achieve the optimum encoding */
-	uint32_t lowerweight = 0;
-	uint32_t upperweight = sdatacount * 2;
+	lowerweight = 0;
+	upperweight = sdatacount * 2;
 	while (1)
 	{
 		/* build a tree using the current weight */
@@ -359,11 +369,14 @@ static int huffman_tree_node_compare(const void *item1, const void *item2)
 
 int huffman_build_tree(struct huffman_decoder* decoder, uint32_t totaldata, uint32_t totalweight)
 {
+	int curcode;
+	int nextalloc;
+	int listitems = 0;
+	int maxbits = 0;
 	/* make a list of all non-zero nodes */
 	struct node_t** list = (struct node_t**)malloc(sizeof(struct node_t*) * decoder->numcodes * 2);
-	int listitems = 0;
 	memset(decoder->huffnode, 0, decoder->numcodes * sizeof(decoder->huffnode[0]));
-	for (int curcode = 0; curcode < decoder->numcodes; curcode++)
+	for (curcode = 0; curcode < decoder->numcodes; curcode++)
 		if (decoder->datahisto[curcode] != 0)
 		{
 			list[listitems++] = &decoder->huffnode[curcode];
@@ -395,7 +408,7 @@ int huffman_build_tree(struct huffman_decoder* decoder, uint32_t totaldata, uint
 #endif
 
 	/* now build the tree */
-	int nextalloc = decoder->numcodes;
+	nextalloc = decoder->numcodes;
 	while (listitems > 1)
 	{
 		/* remove lowest two items */
@@ -421,8 +434,7 @@ int huffman_build_tree(struct huffman_decoder* decoder, uint32_t totaldata, uint
 	}
 
 	/* compute the number of bits in each code, and fill in another histogram */
-	int maxbits = 0;
-	for (int curcode = 0; curcode < decoder->numcodes; curcode++)
+	for (curcode = 0; curcode < decoder->numcodes; curcode++)
 	{
 		struct node_t* node = &decoder->huffnode[curcode];
 		node->numbits = 0;
@@ -453,9 +465,11 @@ int huffman_build_tree(struct huffman_decoder* decoder, uint32_t totaldata, uint
 
 enum huffman_error huffman_assign_canonical_codes(struct huffman_decoder* decoder)
 {
+	int curcode, codelen;
+	uint32_t curstart = 0;
 	/* build up a histogram of bit lengths */
 	uint32_t bithisto[33] = { 0 };
-	for (int curcode = 0; curcode < decoder->numcodes; curcode++)
+	for (curcode = 0; curcode < decoder->numcodes; curcode++)
 	{
 		struct node_t* node = &decoder->huffnode[curcode];
 		if (node->numbits > decoder->maxbits)
@@ -465,8 +479,7 @@ enum huffman_error huffman_assign_canonical_codes(struct huffman_decoder* decode
 	}
 
 	/* for each code length, determine the starting code number */
-	uint32_t curstart = 0;
-	for (int codelen = 32; codelen > 0; codelen--)
+	for (codelen = 32; codelen > 0; codelen--)
 	{
 		uint32_t nextstart = (curstart + bithisto[codelen]) >> 1;
 		if (codelen != 1 && nextstart * 2 != (curstart + bithisto[codelen]))
@@ -476,7 +489,7 @@ enum huffman_error huffman_assign_canonical_codes(struct huffman_decoder* decode
 	}
 
 	/* now assign canonical codes */
-	for (int curcode = 0; curcode < decoder->numcodes; curcode++)
+	for (curcode = 0; curcode < decoder->numcodes; curcode++)
 	{
 		struct node_t* node = &decoder->huffnode[curcode];
 		if (node->numbits > 0)
@@ -493,8 +506,9 @@ enum huffman_error huffman_assign_canonical_codes(struct huffman_decoder* decode
 
 void huffman_build_lookup_table(struct huffman_decoder* decoder)
 {
+	int curcode;
 	/* iterate over all codes */
-	for (int curcode = 0; curcode < decoder->numcodes; curcode++)
+	for (curcode = 0; curcode < decoder->numcodes; curcode++)
 	{
 		/* process all nodes which have non-zero bits */
 		struct node_t* node = &decoder->huffnode[curcode];