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-rw-r--r--engines/sci/scicore/decompress0.cpp123
1 files changed, 52 insertions, 71 deletions
diff --git a/engines/sci/scicore/decompress0.cpp b/engines/sci/scicore/decompress0.cpp
index c132edebd1..4768e033de 100644
--- a/engines/sci/scicore/decompress0.cpp
+++ b/engines/sci/scicore/decompress0.cpp
@@ -33,13 +33,11 @@
namespace Sci {
-/* #define _SCI_DECOMPRESS_DEBUG */
+//#define _SCI_DECOMPRESS_DEBUG
-/* 9-12 bit LZW encoding */
-int
-decrypt1(guint8 *dest, guint8 *src, int length, int complength)
-/* Doesn't do length checking yet */
-{
+// 9-12 bit LZW encoding
+int decrypt1(guint8 *dest, guint8 *src, int length, int complength) {
+ // Doesn't do length checking yet
/* Theory: Considering the input as a bit stream, we get a series of
** 9 bit elements in the beginning. Every one of them is a 'token'
** and either represents a literal (if < 0x100), or a link to a previous
@@ -56,16 +54,16 @@ decrypt1(guint8 *dest, guint8 *src, int length, int complength)
** be faster than the recursive approach.
*/
- guint16 bitlen = 9; /* no. of bits to read (max. 12) */
+ guint16 bitlen = 9; // no. of bits to read (max. 12)
guint16 bitmask = 0x01ff;
- guint16 bitctr = 0; /* current bit position */
- guint16 bytectr = 0; /* current byte position */
- guint16 token; /* The last received value */
- guint16 maxtoken = 0x200; /* The biggest token */
+ guint16 bitctr = 0; // current bit position
+ guint16 bytectr = 0; // current byte position
+ guint16 token; // The last received value
+ guint16 maxtoken = 0x200; // The biggest token
- guint16 tokenlist[4096]; /* pointers to dest[] */
- guint16 tokenlengthlist[4096]; /* char length of each token */
- guint16 tokenctr = 0x102; /* no. of registered tokens (starts here)*/
+ guint16 tokenlist[4096]; // pointers to dest[]
+ guint16 tokenlengthlist[4096]; // char length of each token
+ guint16 tokenctr = 0x102; // no. of registered tokens (starts here)
guint16 tokenlastlength = 0;
@@ -88,14 +86,14 @@ decrypt1(guint8 *dest, guint8 *src, int length, int complength)
bytectr++;
}
- if (token == 0x101) return 0; /* terminator */
- if (token == 0x100) { /* reset command */
+ if (token == 0x101)
+ return 0; // terminator
+ if (token == 0x100) { // reset command
maxtoken = 0x200;
bitlen = 9;
bitmask = 0x01ff;
tokenctr = 0x0102;
} else {
-
{
int i;
@@ -104,18 +102,16 @@ decrypt1(guint8 *dest, guint8 *src, int length, int complength)
#ifdef _SCI_DECOMPRESS_DEBUG
error("decrypt1: Bad token %x", token);
#endif
- /* Well this is really bad */
- /* May be it should throw something like SCI_ERROR_DECOMPRESSION_INSANE */
+ // Well this is really bad
+ // May be it should throw something like SCI_ERROR_DECOMPRESSION_INSANE
} else {
tokenlastlength = tokenlengthlist[token] + 1;
if (destctr + tokenlastlength > length) {
#ifdef _SCI_DECOMPRESS_DEBUG
-
- /* For me this seems a normal situation, It's necessary to handle it*/
+ // For me this seems a normal situation, It's necessary to handle it
printf("decrypt1: Trying to write beyond the end of array(len=%d, destctr=%d, tok_len=%d)",
length, destctr, tokenlastlength);
#endif
-
i = 0;
for (; destctr < length; destctr++) {
dest[destctr++] = dest [tokenlist[token] + i];
@@ -144,30 +140,26 @@ decrypt1(guint8 *dest, guint8 *src, int length, int complength)
bitmask <<= 1;
bitmask |= 1;
maxtoken <<= 1;
- } else continue; /* no further tokens allowed */
+ } else
+ continue; // no further tokens allowed
}
tokenlist[tokenctr] = destctr - tokenlastlength;
tokenlengthlist[tokenctr++] = tokenlastlength;
-
}
-
}
return 0;
-
}
-
-/* Huffman-style token encoding */
+// Huffman-style token encoding
/***************************************************************************/
/* This code was taken from Carl Muckenhoupt's sde.c, with some minor */
/* modifications. */
/***************************************************************************/
-/* decrypt2 helper function */
-gint16 getc2(guint8 *node, guint8 *src,
- guint16 *bytectr, guint16 *bitctr, int complength) {
+// decrypt2 helper function
+gint16 getc2(guint8 *node, guint8 *src, guint16 *bytectr, guint16 *bitctr, int complength) {
guint16 next;
while (node[1] != 0) {
@@ -179,7 +171,7 @@ gint16 getc2(guint8 *node, guint8 *src,
}
if (value & 0x80) {
- next = node[1] & 0x0f; /* low 4 bits */
+ next = node[1] & 0x0f; // low 4 bits
if (next == 0) {
guint16 result = (src[*bytectr] << (*bitctr));
@@ -192,17 +184,17 @@ gint16 getc2(guint8 *node, guint8 *src,
return (result | 0x100);
}
} else {
- next = node[1] >> 4; /* high 4 bits */
+ next = node[1] >> 4; // high 4 bits
}
node += next << 1;
}
+
return getInt16(node);
}
-/* Huffman token decryptor */
-int decrypt2(guint8* dest, guint8* src, int length, int complength)
-/* no complength checking atm */
-{
+// Huffman token decryptor
+int decrypt2(guint8* dest, guint8* src, int length, int complength) {
+ // no complength checking atm */
guint8 numnodes, terminator;
guint8 *nodes;
gint16 c;
@@ -213,9 +205,9 @@ int decrypt2(guint8* dest, guint8* src, int length, int complength)
bytectr = 2 + (numnodes << 1);
nodes = src + 2;
- while (((c = getc2(nodes, src, &bytectr, &bitctr, complength))
- != (0x0100 | terminator)) && (c >= 0)) {
- if (length-- == 0) return SCI_ERROR_DECOMPRESSION_OVERFLOW;
+ while (((c = getc2(nodes, src, &bytectr, &bitctr, complength)) != (0x0100 | terminator)) && (c >= 0)) {
+ if (length-- == 0)
+ return SCI_ERROR_DECOMPRESSION_OVERFLOW;
*dest = (guint8)c;
dest++;
@@ -224,22 +216,19 @@ int decrypt2(guint8* dest, guint8* src, int length, int complength)
return (c == -1) ? SCI_ERROR_DECOMPRESSION_OVERFLOW : 0;
}
-/***************************************************************************/
-/* Carl Muckenhoupt's decompression code ends here */
-/***************************************************************************/
+
+// Carl Muckenhoupt's decompression code ends here
int sci0_get_compression_method(Common::ReadStream &stream) {
guint16 compressedLength;
guint16 compressionMethod;
guint16 result_size;
- /* Dummy variable */
+ // Dummy variable
if (stream.read(&result_size, 2) != 2)
return SCI_ERROR_IO_ERROR;
- if ((stream.read(&compressedLength, 2) != 2) ||
- (stream.read(&result_size, 2) != 2) ||
- (stream.read(&compressionMethod, 2) != 2))
+ if ((stream.read(&compressedLength, 2) != 2) || (stream.read(&result_size, 2) != 2) || (stream.read(&compressionMethod, 2) != 2))
return SCI_ERROR_IO_ERROR;
#ifdef WORDS_BIGENDIAN
@@ -249,7 +238,6 @@ int sci0_get_compression_method(Common::ReadStream &stream) {
return compressionMethod;
}
-
int decompress0(resource_t *result, Common::ReadStream &stream, int sci_version) {
uint16 compressedLength;
uint16 compressionMethod;
@@ -268,9 +256,7 @@ int decompress0(resource_t *result, Common::ReadStream &stream, int sci_version)
if ((result->number > sci_max_resource_nr[sci_version]) || (result->type > sci_invalid_resource))
return SCI_ERROR_DECOMPRESSION_INSANE;
- if ((stream.read(&compressedLength, 2) != 2) ||
- (stream.read(&result_size, 2) != 2) ||
- (stream.read(&compressionMethod, 2) != 2))
+ if ((stream.read(&compressedLength, 2) != 2) || (stream.read(&result_size, 2) != 2) || (stream.read(&compressionMethod, 2) != 2))
return SCI_ERROR_IO_ERROR;
#ifdef WORDS_BIGENDIAN
@@ -282,18 +268,18 @@ int decompress0(resource_t *result, Common::ReadStream &stream, int sci_version)
if (result->size > SCI_MAX_RESOURCE_SIZE)
return SCI_ERROR_RESOURCE_TOO_BIG;
- /* With SCI0, this simply cannot happen. */
+ // With SCI0, this simply cannot happen.
if (compressedLength > 4)
compressedLength -= 4;
- else { /* Object has size zero (e.g. view.000 in sq3) (does this really exist?) */
+ else { // Object has size zero (e.g. view.000 in sq3) (does this really exist?)
result->data = 0;
result->status = SCI_STATUS_NOMALLOC;
return SCI_ERROR_EMPTY_OBJECT;
}
buffer = (guint8*)sci_malloc(compressedLength);
- result->data = (unsigned char*)sci_malloc(result->size);
+ result->data = (unsigned char *)sci_malloc(result->size);
if (stream.read(buffer, compressedLength) != compressedLength) {
free(result->data);
@@ -303,18 +289,13 @@ int decompress0(resource_t *result, Common::ReadStream &stream, int sci_version)
#ifdef _SCI_DECOMPRESS_DEBUG
- error("Resource %s.%03hi encrypted with method %hi at %.2f%%"
- " ratio\n",
- sci_resource_types[result->type], result->number, compressionMethod,
- (result->size == 0) ? -1.0 :
- (100.0 * compressedLength / result->size));
- error(" compressedLength = 0x%hx, actualLength=0x%hx\n",
- compressedLength, result->size);
+ error("Resource %s.%03hi encrypted with method %hi at %.2f%% ratio\n", sci_resource_types[result->type],
+ result->number, compressionMethod, (result->size == 0) ? -1.0 : (100.0 * compressedLength / result->size));
+ error(" compressedLength = 0x%hx, actualLength=0x%hx\n", compressedLength, result->size);
#endif
switch (compressionMethod) {
-
- case 0: /* no compression */
+ case 0: // no compression
if (result->size != compressedLength) {
free(result->data);
result->data = NULL;
@@ -326,10 +307,10 @@ int decompress0(resource_t *result, Common::ReadStream &stream, int sci_version)
result->status = SCI_STATUS_ALLOCATED;
break;
- case 1: /* LZW compression */
+ case 1: // LZW compression
if (decrypt1(result->data, buffer, result->size, compressedLength)) {
free(result->data);
- result->data = 0; /* So that we know that it didn't work */
+ result->data = 0; // So that we know that it didn't work
result->status = SCI_STATUS_NOMALLOC;
free(buffer);
return SCI_ERROR_DECOMPRESSION_OVERFLOW;
@@ -337,10 +318,10 @@ int decompress0(resource_t *result, Common::ReadStream &stream, int sci_version)
result->status = SCI_STATUS_ALLOCATED;
break;
- case 2: /* Some sort of Huffman encoding */
+ case 2: // Some sort of Huffman encoding
if (decrypt2(result->data, buffer, result->size, compressedLength)) {
free(result->data);
- result->data = 0; /* So that we know that it didn't work */
+ result->data = 0; // So that we know that it didn't work
result->status = SCI_STATUS_NOMALLOC;
free(buffer);
return SCI_ERROR_DECOMPRESSION_OVERFLOW;
@@ -349,17 +330,17 @@ int decompress0(resource_t *result, Common::ReadStream &stream, int sci_version)
break;
default:
- error("Resource %s.%03hi: Compression method %hi not "
- "supported", sci_resource_types[result->type], result->number,
- compressionMethod);
+ error("Resource %s.%03hi: Compression method %hi not supported", sci_resource_types[result->type],
+ result->number, compressionMethod);
free(result->data);
- result->data = 0; /* So that we know that it didn't work */
+ result->data = 0; // So that we know that it didn't work
result->status = SCI_STATUS_NOMALLOC;
free(buffer);
return SCI_ERROR_UNKNOWN_COMPRESSION;
}
free(buffer);
+
return 0;
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-02-08 18:38:05 +0000