From 6b250f8c9be45a4076504263fddab77f58ee9a6a Mon Sep 17 00:00:00 2001 From: Filippos Karapetis Date: Fri, 7 Jan 2011 18:25:38 +0000 Subject: SCI2/2.1: Improvements to the find_callk debug function, and some kernel function updates - Improved the find_callk function to properly find the end of script objects, by monitoring jump calls - Added three extra special calls to find_callk: find kernel function calls to dummy, unused and unmapped kernel functions - Updated several kernel function calls because of the above functionality - The above functionality has also uncovered a VM bug in some SCI2/2.1 opcode - added a FIXME for it svn-id: r55151 --- engines/sci/console.cpp | 106 ++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 88 insertions(+), 18 deletions(-) (limited to 'engines/sci/console.cpp') diff --git a/engines/sci/console.cpp b/engines/sci/console.cpp index e25b4cdc1a..c515d45a1a 100644 --- a/engines/sci/console.cpp +++ b/engines/sci/console.cpp @@ -2710,27 +2710,13 @@ bool Console::cmdDisassembleAddress(int argc, const char **argv) { return true; } -bool Console::cmdFindKernelFunctionCall(int argc, const char **argv) { - if (argc < 2) { - DebugPrintf("Finds the scripts and methods that call a specific kernel function.\n"); - DebugPrintf("Usage: %s \n", argv[0]); - DebugPrintf("Example: %s Display\n", argv[0]); - return true; - } - - // Find the number of the kernel function call - int kernelFuncNum = _engine->getKernel()->findKernelFuncPos(argv[1]); - - if (kernelFuncNum < 0) { - DebugPrintf("Invalid kernel function requested\n"); - return true; - } - +void Console::printKernelCallsFound(int kernelFuncNum, bool showFoundScripts) { Common::List *resources = _engine->getResMan()->listResources(kResourceTypeScript); Common::sort(resources->begin(), resources->end()); Common::List::iterator itr = resources->begin(); - DebugPrintf("%d scripts found, dissassembling...\n", resources->size()); + if (showFoundScripts) + DebugPrintf("%d scripts found, dissassembling...\n", resources->size()); int scriptSegment; Script *script; @@ -2762,6 +2748,7 @@ bool Console::cmdFindKernelFunctionCall(int argc, const char **argv) { int16 opparams[4]; byte extOpcode; byte opcode; + uint16 maxJmpOffset = 0; while (true) { offset += readPMachineInstruction(script->getBuf(offset), extOpcode, opparams); @@ -2778,8 +2765,28 @@ bool Console::cmdFindKernelFunctionCall(int argc, const char **argv) { } } + // Monitor all jump opcodes (bt, bnt and jmp), so that if + // there is a jump after a ret, we don't stop processing + if (opcode == op_bt || opcode == op_bnt || opcode == op_jmp) { + uint16 curJmpOffset = offset + (uint16)opparams[0]; + if (curJmpOffset > maxJmpOffset) + maxJmpOffset = curJmpOffset; + // FIXME: There seems to be a bug in the way we handle the SCI2 debug opcode + // (i.e. 0x7e/0x3f), which is probably why the bugs below occur + if (maxJmpOffset >= script->getBufSize()) { + warning("Called from script %d, object %s, method %s(%d) with %d parameters", + itr->getNumber(), objName, + _engine->getKernel()->getSelectorName(obj->getFuncSelector(i)).c_str(), i, 0); + warning("Script %d has a jump to an invalid offset (%d, script size is %d) - adjusting", + script->getScriptNumber(), maxJmpOffset, script->getBufSize()); + maxJmpOffset = script->getBufSize() - 1; + } + } + // Check for end of function/script - if (opcode == op_ret || offset >= script->getBufSize()) + if (offset >= script->getBufSize()) + break; + if (opcode == op_ret)// && offset >= maxJmpOffset) break; } // while (true) } // for (uint16 i = 0; i < obj->getMethodCount(); i++) @@ -2790,6 +2797,69 @@ bool Console::cmdFindKernelFunctionCall(int argc, const char **argv) { } delete resources; +} + +bool Console::cmdFindKernelFunctionCall(int argc, const char **argv) { + if (argc < 2) { + DebugPrintf("Finds the scripts and methods that call a specific kernel function.\n"); + DebugPrintf("Usage: %s \n", argv[0]); + DebugPrintf("Example: %s Display\n", argv[0]); + DebugPrintf("Special usage:\n"); + DebugPrintf("%s Dummy - find all calls to actual dummy functions " + "(mapped to kDummy, and dummy in the kernel table). " + "There shouldn't be calls to these (apart from a known " + "one in Shivers)\n", argv[0]); + DebugPrintf("%s Unused - find all calls to unused functions (mapped to " + "kDummy - i.e. mapped in SSCI but dummy in ScummVM, thus " + "they'll error out when called). Only debug scripts should " + "be calling these\n", argv[0]); + DebugPrintf("%s Unmapped - find all calls to currently unmapped or " + "unimplemented functions (mapped to kStub/kStubNull)\n", argv[0]); + return true; + } + + Kernel *kernel = _engine->getKernel(); + Common::String funcName(argv[1]); + + if (funcName != "Dummy" && funcName != "Unused" && funcName != "Unmapped") { + // Find the number of the kernel function call + int kernelFuncNum = kernel->findKernelFuncPos(argv[1]); + + if (kernelFuncNum < 0) { + DebugPrintf("Invalid kernel function requested\n"); + return true; + } + + printKernelCallsFound(kernelFuncNum, true); + } else if (funcName == "Dummy") { + // Find all actual dummy kernel functions (mapped to kDummy, and dummy + // in the kernel table) + for (uint i = 0; i < kernel->_kernelFuncs.size(); i++) { + if (kernel->_kernelFuncs[i].function == &kDummy && kernel->getKernelName(i) == "Dummy") { + DebugPrintf("Searching for kernel function %d (%s)...\n", i, kernel->getKernelName(i).c_str()); + printKernelCallsFound(i, false); + } + } + } else if (funcName == "Unused") { + // Find all actual dummy kernel functions (mapped to kDummy - i.e. + // mapped in SSCI but dummy in ScummVM, thus they'll error out when + // called) + for (uint i = 0; i < kernel->_kernelFuncs.size(); i++) { + if (kernel->_kernelFuncs[i].function == &kDummy && kernel->getKernelName(i) != "Dummy") { + DebugPrintf("Searching for kernel function %d (%s)...\n", i, kernel->getKernelName(i).c_str()); + printKernelCallsFound(i, false); + } + } + } else if (funcName == "Unmapped") { + // Find all unmapped kernel functions (mapped to kStub/kStubNull) + for (uint i = 0; i < kernel->_kernelFuncs.size(); i++) { + if (kernel->_kernelFuncs[i].function == &kStub || + kernel->_kernelFuncs[i].function == &kStubNull) { + DebugPrintf("Searching for kernel function %d (%s)...\n", i, kernel->getKernelName(i).c_str()); + printKernelCallsFound(i, false); + } + } + } return true; } -- cgit v1.2.3