change track loading to use stdio (FILE)

src/editor.c

@@ -33,6 +33,7 @@
 #include "peep/staff.h"
 #include "ride/ride.h"
 #include "util/sawyercoding.h"
+#include "util/util.h"
 #include "world/banner.h"
 #include "world/map.h"
 #include "world/park.h"
@@ -247,12 +248,8 @@ static int editor_load_landscape_from_sv4(const char *path)
 		return 0;
 	}
 
-	// Get length
-	fseek(fp, 0, SEEK_END);
-	fpLength = ftell(fp);
-	rewind(fp);
-
 	// Read whole file into a buffer
+	fpLength = fsize(fp);
 	fpBuffer = malloc(fpLength);
 	fread(fpBuffer, fpLength, 1, fp);
 	fclose(fp);

src/ride/track.c

@@ -18,10 +18,10 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *****************************************************************************/
 
-#include <string.h>
-#include <windows.h>
 #include "../addresses.h"
 #include "../platform/osinterface.h"
+#include "../util/sawyercoding.h"
+#include "../util/util.h"
 #include "ride.h"
 #include "track.h"
 
@@ -229,26 +229,10 @@ void track_load_list(ride_list_item item)
     RCT2_CALLPROC_X(0x006CED50, 0, 0, 0, *((uint16*)&item), 0, 0, 0);
 }
 
-/**
- *
- *  rct2: 0x00676EBA
- */
-static uint8 sub_676EBA()
+static void read(void *dst, void **src, int length)
 {
-	int eax, ebx, ecx, edx, esi, edi, ebp;
-	RCT2_CALLFUNC_X(0x00676EBA, &eax, &ebx, &ecx, &edx, &esi, &edi, &ebp);
-	return eax & 0xFF;
-}
-
-/**
- *
- *  rct2: 0x00676EAF
- */
-static void sub_676EAF(uint8 *esi, int ecx)
-{
-	do {
-		*esi++ = sub_676EBA();
-	} while (--ecx != 0);
+	memcpy(dst, *src, length);
+	*((char**)src) += length;
 }
 
 /**
@@ -258,10 +242,11 @@ static void sub_676EAF(uint8 *esi, int ecx)
  */
 int sub_67726A(const char *path)
 {
-	HANDLE *hFile;
+	FILE *fp;
+	long fpLength;
 	const char *ch;
-	char trackFilename[MAX_PATH], *dst;
-	int i;
+	char trackFilename[MAX_PATH], *fpBuffer, *decoded, *src, *dst;
+	int i, decodedLength;
 	uint8* edi;
 
 	RCT2_GLOBAL(0x009AAC54, uint8) = 1;
@@ -275,30 +260,41 @@ int sub_67726A(const char *path)
 	}
 	*dst = 0;
 
-	hFile = osinterface_file_open(path);
-	if (hFile == INVALID_HANDLE_VALUE)
+	fp = fopen(path, "rb");
+	if (fp == NULL)
 		return 0;
 
-	RCT2_GLOBAL(0x009E382C, HANDLE) = hFile;
-	if (!RCT2_CALLPROC_X(0x006770C1, 0, 0, 0, 0, 0, 0, 0)) {
-		CloseHandle(hFile);
-		return 0;
-	}
+	// Read whole file into a buffer
+	fpLength = fsize(fp);
+	fpBuffer = malloc(fpLength);
+	fread(fpBuffer, fpLength, 1, fp);
+	fclose(fp);
 
-	RCT2_CALLPROC_EBPSAFE(0x00676E7A);
+	// Validate the checksum
+	// Not the same checksum algorithm as scenarios and saved games
+	// sub_6770C1();
+
+	// Decode the track data
+	decoded = malloc(0x10000);
+	decodedLength = sawyercoding_decode_td6(fpBuffer, decoded, fpLength);
+	realloc(decoded, decodedLength);
+	free(fpBuffer);
+
+	// Read decoded data
+	src = decoded;
 	memset((void*)0x009D81D8, 0, 67);
-	sub_676EAF((void*)0x009D8178, 32);
+	read((void*)0x009D8178, &src, 32);
 
 	uint8 al = RCT2_GLOBAL(0x009D817F, uint8) >> 2;
 	if (al >= 2)
-		sub_676EAF((void*)0x009D8198, 40);
+		read((void*)0x009D8198, &src, 40);
 
-	sub_676EAF((void*)0x009D81C0, 24);
+	read((void*)0x009D81C0, &src, 24);
 	al = RCT2_GLOBAL(0x009D817F, uint8) >> 2;
 	if (al != 0)
-		sub_676EAF((void*)0x009D81D8, al == 1 ? 140 : 67);
+		read((void*)0x009D81D8, &src, al == 1 ? 140 : 67);
 
-	sub_676EAF((void*)0x009D821B, 24572);
+	read((void*)0x009D821B, &src, 24572);
 	al = RCT2_GLOBAL(0x009D817F, uint8) >> 2;
 	if (al < 2) {
 		if (RCT2_GLOBAL(0x009D8178, uint8) == 20) {
@@ -317,9 +313,9 @@ int sub_67726A(const char *path)
 			memset(edi, 255, (uint8*)0x009DE217 - edi);
 		}
 	}
+	free(decoded);
 
-	CloseHandle(hFile);
-
+	// 
 	al = RCT2_GLOBAL(0x009D817F, uint8) >> 2;
 	if (al > 2)
 		return 0;

src/util/sawyercoding.c

@@ -345,4 +345,9 @@ int sawyercoding_encode_sv4(char *src, char *dst, int length)
 	*((uint32*)&dst[encodedLength]) = checksum;
 
 	return encodedLength + 4;
+}
+
+int sawyercoding_decode_td6(char *src, char *dst, int length)
+{
+	return decode_chunk_rle(src, dst, length - 4);
 }

src/util/sawyercoding.h

@@ -43,5 +43,6 @@ int sawyercoding_write_chunk_buffer(uint8 *dst_file, uint8* buffer, sawyercoding
 int sawyercoding_decode_sv4(char *src, char *dst, int length);
 int sawyercoding_decode_sc4(char *src, char *dst, int length);
 int sawyercoding_encode_sv4(char *src, char *dst, int length);
+int sawyercoding_decode_td6(char *src, char *dst, int length);
 
 #endif

src/util/util.c

@@ -39,4 +39,16 @@ int mph_to_kmph(int mph)
 	// 1 mph = 1.60934 kmph
 	// RCT2 approximates as 1.609375
 	return (mph * 1648) / 1024;
+}
+
+long fsize(FILE *fp)
+{
+	long originalPosition, size;
+
+	originalPosition = ftell(fp);
+	fseek(fp, 0, SEEK_END);
+	size = ftell(fp);
+	fseek(fp, originalPosition, SEEK_SET);
+
+	return size;
 }

src/util/util.h

@@ -21,8 +21,12 @@
 #ifndef _UTIL_H_
 #define _UTIL_H_
 
+#include "../common.h"
+
 int squaredmetres_to_squaredfeet(int squaredMetres);
 int metres_to_feet(int metres);
 int mph_to_kmph(int mph);
 
+long fsize(FILE *fp);
+
 #endif