From: Jean-Paul Mari <djipi.mari@gmail.com>
Date: Sun, 16 Sep 2018 05:41:16 +0000 (-0400)
Subject: Added LEB128 decoding functions
X-Git-Tag: v2.1.3-R4~33
X-Git-Url: http://git.hcoop.net/clinton/Virtual-Jaguar-Rx.git/commitdiff_plain/68ca35f35bfa4122b75f65c51fff8de3d8de40e4?ds=sidebyside

Added LEB128 decoding functions
---

diff --git a/Win-VS2017/virtualjaguar.vcxproj b/Win-VS2017/virtualjaguar.vcxproj
index 3561824..4f8b2c8 100644
--- a/Win-VS2017/virtualjaguar.vcxproj
+++ b/Win-VS2017/virtualjaguar.vcxproj
@@ -286,6 +286,7 @@
     <ClCompile Include="..\src\file.cpp" />
     <ClCompile Include="..\src\gui\keybindingstab.cpp" />
     <ClCompile Include="..\src\gui\modelsbiostab.cpp" />
+    <ClCompile Include="..\src\LEB128.cpp" />
     <ClCompile Include="..\src\log.cpp" />
     <ClCompile Include="..\src\settings.cpp" />
     <ClCompile Include="..\src\unzip.cpp" />
@@ -696,6 +697,7 @@
       <Outputs Condition="'$(Configuration)|$(Platform)'=='Release|x64'">.\GeneratedFiles\$(ConfigurationName)\moc_%(Filename).cpp</Outputs>
       <Command Condition="'$(Configuration)|$(Platform)'=='Release|x64'">"$(QTDIR)\bin\moc.exe"  "%(FullPath)" -o ".\GeneratedFiles\$(ConfigurationName)\moc_%(Filename).cpp"  -D_CRT_SECURE_NO_WARNINGS -D_WINDOWS -DUNICODE -DWIN32 -DWIN64 -D__GCCWIN32__ -DQT_NO_DEBUG -DQT_OPENGL_LIB -DNDEBUG -DQT_CORE_LIB -DQT_GUI_LIB -DQT_WIDGETS_LIB -D_UNICODE "-I." "-I.\..\src" "-I.\..\src\gui" "-I$(QTDIR)\include" "-I$(QTDIR)\include\QtCore" "-I$(QTDIR)\include\QtGui" "-I$(QTDIR)\include\QtWidgets" "-I$(QTDIR)\include\QtOpenGL" "-IC:\SDK\OpenGL\include" "-IC:\SDK\SDL\SDL-1.2.15\include" "-IC:\SDK\DWARF\libdwarf-VS2015\include" "-IC:\SDK\Elf\libelf-0.8.13\include" "-IC:\SDK\zlib\zlib-1.2.11\include" "-I.\GeneratedFiles\$(ConfigurationName)\."</Command>
     </CustomBuild>
+    <ClInclude Include="..\src\LEB128.h" />
     <ClInclude Include="..\src\log.h" />
     <ClInclude Include="..\src\settings.h" />
     <ClInclude Include="..\src\unzip.h" />
diff --git a/Win-VS2017/virtualjaguar.vcxproj.filters b/Win-VS2017/virtualjaguar.vcxproj.filters
index 720a840..bf19ace 100644
--- a/Win-VS2017/virtualjaguar.vcxproj.filters
+++ b/Win-VS2017/virtualjaguar.vcxproj.filters
@@ -400,6 +400,9 @@
     <ClCompile Include="..\src\gui\modelsbiostab.cpp">
       <Filter>Source Files\gui\tab</Filter>
     </ClCompile>
+    <ClCompile Include="..\src\LEB128.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\src\debugger\DWARFManager.h">
@@ -450,6 +453,9 @@
     <ClInclude Include="..\src\settings.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="..\src\LEB128.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <None Include="..\res\alpine-file.png">
diff --git a/src/LEB128.cpp b/src/LEB128.cpp
new file mode 100644
index 0000000..159b5f3
--- /dev/null
+++ b/src/LEB128.cpp
@@ -0,0 +1,46 @@
+
+
+// Decode an unsigned LEB128
+// Algorithm from Appendix C of the DWARF 2, and 3, spec section "7.6"
+unsigned long ReadULEB128(char *addr)
+{
+	unsigned long result = 0;
+	size_t shift = 0;
+	unsigned char byte;
+
+	do
+	{
+		byte = *addr++;
+		result |= (byte & 0x7f) << shift;
+		shift += 7;
+	}
+	while ((byte & 0x80));
+
+	return result;
+}
+
+
+// Decode a signed LEB128
+// Algorithm from Appendix C of the DWARF 2, and 3, spec section "7.6"
+long ReadLEB128(char *addr)
+{
+	long result = 0;
+	size_t shift = 0;
+	unsigned char byte;
+
+	do
+	{
+		byte = *addr++;
+		result |= (byte & 0x7f) << shift;
+		shift += 7;
+	}
+	while ((byte & 0x80));
+
+	if ((shift < (8 * sizeof(result))) && (byte & 0x40))
+	{
+		result |= (~0 << shift);
+	}
+
+	return result;
+}
+
diff --git a/src/LEB128.h b/src/LEB128.h
new file mode 100644
index 0000000..7f2c527
--- /dev/null
+++ b/src/LEB128.h
@@ -0,0 +1,6 @@
+
+// LEB128 handler
+
+//
+extern unsigned long ReadULEB128(char *addr);
+extern long ReadLEB128(char *addr);
diff --git a/virtualjaguar.pro b/virtualjaguar.pro
index 60043d3..c3ca4c0 100644
--- a/virtualjaguar.pro
+++ b/virtualjaguar.pro
@@ -127,7 +127,8 @@ HEADERS = \
 	src/crc32.h \
 	src/settings.h \
 	src/modelsBIOS.h \
-	src/file.h
+	src/file.h \
+	src/LEB128.h
 
 SOURCES = \
 	src/gui/about.cpp \
@@ -178,5 +179,6 @@ SOURCES = \
 	src/crc32.cpp \
 	src/settings.cpp \
 	src/modelsBIOS.cpp \	
-	src/file.cpp
+	src/file.cpp \
+	src/LEB128.cpp
 		
\ No newline at end of file