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author | Colin Snover | 2016-12-31 20:39:57 -0600 |
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committer | Colin Snover | 2017-03-27 19:42:31 -0500 |
commit | 31daa956d62b39429cb6638ed3fb549ac488833a (patch) | |
tree | fa831adefae05d82209b3f565055f7b761ca8691 /engines/sci/graphics/font.cpp | |
parent | 1298762b7665dc1b7aeedf0271eadfb284309ef1 (diff) | |
download | scummvm-rg350-31daa956d62b39429cb6638ed3fb549ac488833a.tar.gz scummvm-rg350-31daa956d62b39429cb6638ed3fb549ac488833a.tar.bz2 scummvm-rg350-31daa956d62b39429cb6638ed3fb549ac488833a.zip |
SCI: Implement bounds-checked reads of game resources
Diffstat (limited to 'engines/sci/graphics/font.cpp')
-rw-r--r-- | engines/sci/graphics/font.cpp | 50 |
1 files changed, 35 insertions, 15 deletions
diff --git a/engines/sci/graphics/font.cpp b/engines/sci/graphics/font.cpp index 2268ec0459..ff2f361d93 100644 --- a/engines/sci/graphics/font.cpp +++ b/engines/sci/graphics/font.cpp @@ -40,16 +40,15 @@ GfxFontFromResource::GfxFontFromResource(ResourceManager *resMan, GfxScreen *scr if (!_resource) { error("font resource %d not found", resourceId); } - _resourceData = _resource->data; - _numChars = READ_SCI32ENDIAN_UINT16(_resourceData + 2); - _fontHeight = READ_SCI32ENDIAN_UINT16(_resourceData + 4); + _numChars = _resource->getUint16SE32At(2); + _fontHeight = _resource->getUint16SE32At(4); _chars = new Charinfo[_numChars]; // filling info for every char for (int16 i = 0; i < _numChars; i++) { - _chars[i].offset = READ_SCI32ENDIAN_UINT16(_resourceData + 6 + i * 2); - _chars[i].width = _resourceData[_chars[i].offset]; - _chars[i].height = _resourceData[_chars[i].offset + 1]; + _chars[i].offset = _resource->getUint16SE32At(6 + i * 2); + _chars[i].width = _resource->getUint8At(_chars[i].offset); + _chars[i].height = _resource->getUint8At(_chars[i].offset + 1); } } @@ -62,20 +61,33 @@ GuiResourceId GfxFontFromResource::getResourceId() { return _resourceId; } -byte GfxFontFromResource::getHeight() { +uint8 GfxFontFromResource::getHeight() { return _fontHeight; } -byte GfxFontFromResource::getCharWidth(uint16 chr) { +uint8 GfxFontFromResource::getCharWidth(uint16 chr) { return chr < _numChars ? _chars[chr].width : 0; } -byte GfxFontFromResource::getCharHeight(uint16 chr) { +uint8 GfxFontFromResource::getCharHeight(uint16 chr) { return chr < _numChars ? _chars[chr].height : 0; } -byte *GfxFontFromResource::getCharData(uint16 chr) { - return chr < _numChars ? _resourceData + _chars[chr].offset + 2 : 0; +SciSpan<const byte> GfxFontFromResource::getCharData(uint16 chr) { + if (chr >= _numChars) { + return SciSpan<const byte>(); + } + + const uint32 size = (chr + 1 >= _numChars ? _resource->size() : _chars[chr + 1].offset) - _chars[chr].offset - 2; + return _resource->subspan(_chars[chr].offset + 2, size); } void GfxFontFromResource::draw(uint16 chr, int16 top, int16 left, byte color, bool greyedOutput) { + if (chr >= _numChars) { + // SSCI silently ignores attempts to draw characters that do not exist + // in the font; for now, emit warnings if this happens, to learn if + // it leads to any bugs + warning("%s is missing glyph %d", _resource->name().c_str(), chr); + return; + } + // Make sure we're comparing against the correct dimensions // If the font we're drawing is already upscaled, make sure we use the full screen width/height uint16 screenWidth = _screen->fontIsUpscaled() ? _screen->getDisplayWidth() : _screen->getWidth(); @@ -87,13 +99,13 @@ void GfxFontFromResource::draw(uint16 chr, int16 top, int16 left, byte color, bo int y = 0; int16 greyedTop = top; - byte *pIn = getCharData(chr); + SciSpan<const byte> charData = getCharData(chr); for (int i = 0; i < charHeight; i++, y++) { if (greyedOutput) mask = ((greyedTop++) % 2) ? 0xAA : 0x55; for (int done = 0; done < charWidth; done++) { if ((done & 7) == 0) // fetching next data byte - b = *(pIn++) & mask; + b = *(charData++) & mask; if (b & 0x80) // if MSB is set - paint it _screen->putFontPixel(top, left + done, y, color); b = b << 1; @@ -104,19 +116,27 @@ void GfxFontFromResource::draw(uint16 chr, int16 top, int16 left, byte color, bo #ifdef ENABLE_SCI32 void GfxFontFromResource::drawToBuffer(uint16 chr, int16 top, int16 left, byte color, bool greyedOutput, byte *buffer, int16 bufWidth, int16 bufHeight) { + if (chr >= _numChars) { + // SSCI silently ignores attempts to draw characters that do not exist + // in the font; for now, emit warnings if this happens, to learn if + // it leads to any bugs + warning("%s is missing glyph %d", _resource->name().c_str(), chr); + return; + } + int charWidth = MIN<int>(getCharWidth(chr), bufWidth - left); int charHeight = MIN<int>(getCharHeight(chr), bufHeight - top); byte b = 0, mask = 0xFF; int y = 0; int16 greyedTop = top; - byte *pIn = getCharData(chr); + SciSpan<const byte> charData = getCharData(chr); for (int i = 0; i < charHeight; i++, y++) { if (greyedOutput) mask = ((greyedTop++) % 2) ? 0xAA : 0x55; for (int done = 0; done < charWidth; done++) { if ((done & 7) == 0) // fetching next data byte - b = *(pIn++) & mask; + b = *(charData++) & mask; if (b & 0x80) { // if MSB is set - paint it int offset = (top + y) * bufWidth + (left + done); buffer[offset] = color; |