[Scummvm-git-logs] scummvm master -> d06bcf29c5a8b7853db1c40e912e6637fba3c5f3

[bluegr]

This automated email contains information about 2 new commits which have been
pushed to the 'scummvm' repo located at https://github.com/scummvm/scummvm .

Summary:
39f0c165c3 M4: Avoid unaligned memory access in the memory stash code
d06bcf29c5 M4: Avoid unaligned memory access in the font loader


Commit: 39f0c165c30118919ba082372acdd18ea72f2b3d
    https://github.com/scummvm/scummvm/commit/39f0c165c30118919ba082372acdd18ea72f2b3d
Author: Cameron Cawley (ccawley2011 at gmail.com)
Date: 2024-10-30T14:01:32+02:00

Commit Message:
M4: Avoid unaligned memory access in the memory stash code

Changed paths:
    engines/m4/mem/mem.cpp


diff --git a/engines/m4/mem/mem.cpp b/engines/m4/mem/mem.cpp
index ea68f89c00d..cca1fa6c14a 100644
--- a/engines/m4/mem/mem.cpp
+++ b/engines/m4/mem/mem.cpp
@@ -67,8 +67,8 @@ bool mem_register_stash_type(int32 *memType, int32 blockSize, int32 maxNumReques
 
 		_G(requests)[i] = maxNumRequests;
 
-		_G(memBlock)[i] = mem_alloc((blockSize + 1) * maxNumRequests, name.c_str());
-		memset(_G(memBlock)[i], 0, (blockSize + 1) * maxNumRequests);
+		_G(memBlock)[i] = mem_alloc((blockSize + sizeof(uintptr)) * maxNumRequests, name.c_str());
+		memset(_G(memBlock)[i], 0, (blockSize + sizeof(uintptr)) * maxNumRequests);
 
 		return true;
 	}
@@ -80,12 +80,12 @@ bool mem_register_stash_type(int32 *memType, int32 blockSize, int32 maxNumReques
 void mem_free_to_stash(void *mem, int32 memType) {
 	// _G(memBlock)[memType] is block associated with memType
 	int8 *b_ptr = (int8 *)_G(memBlock)[memType];
-	int32 index = ((intptr)mem - (intptr)_G(memBlock)[memType]) / (_G(sizeMem)[memType] + 1);
+	int32 index = ((intptr)mem - (intptr)_G(memBlock)[memType]) / (_G(sizeMem)[memType] + sizeof(uintptr));
 
 	if (index < 0 || index > _G(requests)[memType])
 		error_show(FL, 'MSGF');
 
-	b_ptr += index * (_G(sizeMem)[memType] + 1);
+	b_ptr += index * (_G(sizeMem)[memType] + sizeof(uintptr));
 	*b_ptr = 0;
 }
 
@@ -95,13 +95,13 @@ void *mem_get_from_stash(int32 memType, const Common::String &name) {
 
 	for (i = 0; i < _G(requests)[memType]; i++) {
 		if (!*b_ptr) {
-			*b_ptr = 1;
-			void *result = (void *)(b_ptr + 1);
+			*(uintptr *)b_ptr = 1;
+			void *result = (void *)(b_ptr + sizeof(uintptr));
 			Common::fill((byte *)result, (byte *)result + _G(sizeMem)[memType], 0);
 			return result;
 
 		} else {
-			b_ptr += _G(sizeMem)[memType] + 1;
+			b_ptr += _G(sizeMem)[memType] + sizeof(uintptr);
 		}
 	}
 


Commit: d06bcf29c5a8b7853db1c40e912e6637fba3c5f3
    https://github.com/scummvm/scummvm/commit/d06bcf29c5a8b7853db1c40e912e6637fba3c5f3
Author: Cameron Cawley (ccawley2011 at gmail.com)
Date: 2024-10-30T14:01:32+02:00

Commit Message:
M4: Avoid unaligned memory access in the font loader

Changed paths:
    engines/m4/fileio/sys_file.cpp
    engines/m4/fileio/sys_file.h
    engines/m4/graphics/gr_font.cpp


diff --git a/engines/m4/fileio/sys_file.cpp b/engines/m4/fileio/sys_file.cpp
index 3b86df021f7..3cf0d7fbb9b 100644
--- a/engines/m4/fileio/sys_file.cpp
+++ b/engines/m4/fileio/sys_file.cpp
@@ -631,6 +631,14 @@ int32 SysFile::read(MemHandle bufferHandle, int32 n) {
 	}
 }
 
+byte SysFile::readByte() {
+	byte buf[1];
+	void *ptr = (void *)buf;
+	read(&ptr, 1);
+
+	return buf[0];
+}
+
 uint32 SysFile::readUint32LE() {
 	byte buf[4];
 	void *ptr = (void *)buf;
diff --git a/engines/m4/fileio/sys_file.h b/engines/m4/fileio/sys_file.h
index 4b843b5e8d8..9366c8ba2bc 100644
--- a/engines/m4/fileio/sys_file.h
+++ b/engines/m4/fileio/sys_file.h
@@ -123,6 +123,14 @@ public:
 	uint32 read(MemHandle bufferHandle);
 	int32 read(MemHandle bufferHandle, int32 n);
 
+	/**
+	 * Read in a 8-bit value
+	 */
+	byte readByte();
+	int8 readSByte() {
+		return (int8)readByte();
+	}
+
 	/**
 	 * Read in a 32-bit value
 	 */
diff --git a/engines/m4/graphics/gr_font.cpp b/engines/m4/graphics/gr_font.cpp
index 069dbb37984..614fbae4e69 100644
--- a/engines/m4/graphics/gr_font.cpp
+++ b/engines/m4/graphics/gr_font.cpp
@@ -356,21 +356,15 @@ int32 gr_font_write(Buffer *target, const char *out_string, int32 x, int32 y, in
 }
 
 Font *gr_font_load(const char *fontName) {
-	uint8 buffer[10];
 	uint32 tag;
-	uint32 *bumpf;
 	Font *newFont;
-	void *bufferHandle = &buffer[0];
+	void *bufferHandle;
 
 	SysFile fontFile(fontName, BINARY);
 	if (!fontFile.exists())
 		return nullptr;
 
-	bufferHandle = &buffer[0];
-	fontFile.read(&bufferHandle, 10);
-
-	bumpf = (uint32 *)&buffer[0];
-	tag = convert_intel32(*bumpf);
+	tag = fontFile.readUint32LE();
 	if (tag != 'FONT')
 		error_show(FL, 'FNTL', "font: %s chkpnt: %d", (const char *)fontName, 0);
 
@@ -378,16 +372,12 @@ Font *gr_font_load(const char *fontName) {
 	if (!newFont)
 		error_show(FL, 'OOM!', "_G(font) struct");
 
-	newFont->max_y_size = buffer[4];
-	newFont->max_x_size = buffer[5];
-	newFont->dataSize = *((uint32 *)&buffer[6]);
-	newFont->dataSize = convert_intel32(newFont->dataSize);
+	newFont->max_y_size = fontFile.readByte();
+	newFont->max_x_size = fontFile.readByte();
+	newFont->dataSize = fontFile.readUint32LE();
 
 	// read 'WIDT' into tag
-	bufferHandle = &buffer[0];
-	fontFile.read(&bufferHandle, 4);
-	bumpf = (uint32 *)&buffer[0];
-	tag = convert_intel32(*bumpf);
+	tag = fontFile.readUint32LE();
 	if (tag != 'WIDT')
 		error_show(FL, 'FNTL', "font: %s chkpnt: %d", fontName, 1);
 
@@ -400,10 +390,7 @@ Font *gr_font_load(const char *fontName) {
 	fontFile.read(&bufferHandle, 256);
 
 	// read 'OFFS' into tag
-	bufferHandle = &buffer[0];
-	fontFile.read(&bufferHandle, 4);
-	bumpf = (uint32 *)&buffer[0];
-	tag = convert_intel32(*bumpf);
+	tag = fontFile.readUint32LE();
 	if (tag != 'OFFS')
 		error_show(FL, 'FNTL', "font: %s chkpnt: %d", fontName, 2);
 
@@ -419,10 +406,7 @@ Font *gr_font_load(const char *fontName) {
 		newFont->offset[i] = convert_intel16(newFont->offset[i]);
 
 	// read 'PIXS' into tag
-	bufferHandle = &buffer[0];
-	fontFile.read(&bufferHandle, 4);
-	bumpf = (uint32 *)&buffer[0];
-	tag = convert_intel32(*bumpf);
+	tag = fontFile.readUint32LE();
 	if (tag != 'PIXS')
 		error_show(FL, 'FNTL', "font: %s chkpnt: %d", fontName, 3);