michael@0: // Copyright (c) 2010 Google Inc.
michael@0: // All rights reserved.
michael@0: //
michael@0: // Redistribution and use in source and binary forms, with or without
michael@0: // modification, are permitted provided that the following conditions are
michael@0: // met:
michael@0: //
michael@0: //     * Redistributions of source code must retain the above copyright
michael@0: // notice, this list of conditions and the following disclaimer.
michael@0: //     * Redistributions in binary form must reproduce the above
michael@0: // copyright notice, this list of conditions and the following disclaimer
michael@0: // in the documentation and/or other materials provided with the
michael@0: // distribution.
michael@0: //     * Neither the name of Google Inc. nor the names of its
michael@0: // contributors may be used to endorse or promote products derived from
michael@0: // this software without specific prior written permission.
michael@0: //
michael@0: // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
michael@0: // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
michael@0: // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
michael@0: // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
michael@0: // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
michael@0: // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
michael@0: // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
michael@0: // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
michael@0: // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
michael@0: // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
michael@0: // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
michael@0: 
michael@0: // stackwalker.cc: Generic stackwalker.
michael@0: //
michael@0: // See stackwalker.h for documentation.
michael@0: //
michael@0: // Author: Mark Mentovai
michael@0: 
michael@0: #include "google_breakpad/processor/stackwalker.h"
michael@0: 
michael@0: #include <assert.h>
michael@0: 
michael@0: #include "common/scoped_ptr.h"
michael@0: #include "google_breakpad/processor/call_stack.h"
michael@0: #include "google_breakpad/processor/code_module.h"
michael@0: #include "google_breakpad/processor/code_modules.h"
michael@0: #include "google_breakpad/processor/minidump.h"
michael@0: #include "google_breakpad/processor/stack_frame.h"
michael@0: #include "google_breakpad/processor/stack_frame_symbolizer.h"
michael@0: #include "google_breakpad/processor/system_info.h"
michael@0: #include "processor/linked_ptr.h"
michael@0: #include "common/logging.h"
michael@0: #include "processor/stackwalker_ppc.h"
michael@0: #include "processor/stackwalker_sparc.h"
michael@0: #include "processor/stackwalker_x86.h"
michael@0: #include "processor/stackwalker_amd64.h"
michael@0: #include "processor/stackwalker_arm.h"
michael@0: 
michael@0: namespace google_breakpad {
michael@0: 
michael@0: const int Stackwalker::kRASearchWords = 30;
michael@0: 
michael@0: uint32_t Stackwalker::max_frames_ = 1024;
michael@0: bool Stackwalker::max_frames_set_ = false;
michael@0: 
michael@0: uint32_t Stackwalker::max_frames_scanned_ = 1024;
michael@0: 
michael@0: Stackwalker::Stackwalker(const SystemInfo* system_info,
michael@0:                          MemoryRegion* memory,
michael@0:                          const CodeModules* modules,
michael@0:                          StackFrameSymbolizer* frame_symbolizer)
michael@0:     : system_info_(system_info),
michael@0:       memory_(memory),
michael@0:       modules_(modules),
michael@0:       frame_symbolizer_(frame_symbolizer) {
michael@0:   assert(frame_symbolizer_);
michael@0: }
michael@0: 
michael@0: 
michael@0: bool Stackwalker::Walk(CallStack* stack,
michael@0:                        vector<const CodeModule*>* modules_without_symbols) {
michael@0:   BPLOG_IF(ERROR, !stack) << "Stackwalker::Walk requires |stack|";
michael@0:   assert(stack);
michael@0:   stack->Clear();
michael@0: 
michael@0:   BPLOG_IF(ERROR, !modules_without_symbols) << "Stackwalker::Walk requires "
michael@0:                                             << "|modules_without_symbols|";
michael@0:   assert(modules_without_symbols);
michael@0: 
michael@0:   // Begin with the context frame, and keep getting callers until there are
michael@0:   // no more.
michael@0: 
michael@0:   // Keep track of the number of scanned or otherwise dubious frames seen
michael@0:   // so far, as the caller may have set a limit.
michael@0:   uint32_t n_scanned_frames = 0;
michael@0: 
michael@0:   // Take ownership of the pointer returned by GetContextFrame.
michael@0:   scoped_ptr<StackFrame> frame(GetContextFrame());
michael@0: 
michael@0:   while (frame.get()) {
michael@0:     // frame already contains a good frame with properly set instruction and
michael@0:     // frame_pointer fields.  The frame structure comes from either the
michael@0:     // context frame (above) or a caller frame (below).
michael@0: 
michael@0:     // Resolve the module information, if a module map was provided.
michael@0:     StackFrameSymbolizer::SymbolizerResult symbolizer_result =
michael@0:         frame_symbolizer_->FillSourceLineInfo(modules_, system_info_,
michael@0:                                              frame.get());
michael@0:     if (symbolizer_result == StackFrameSymbolizer::kInterrupt) {
michael@0:       BPLOG(INFO) << "Stack walk is interrupted.";
michael@0:       return false;
michael@0:     }
michael@0: 
michael@0:     // Keep track of modules that have no symbols.
michael@0:     if (symbolizer_result == StackFrameSymbolizer::kError &&
michael@0:         frame->module != NULL) {
michael@0:       bool found = false;
michael@0:       vector<const CodeModule*>::iterator iter;
michael@0:       for (iter = modules_without_symbols->begin();
michael@0:            iter != modules_without_symbols->end();
michael@0:            ++iter) {
michael@0:         if (*iter == frame->module) {
michael@0:           found = true;
michael@0:           break;
michael@0:         }
michael@0:       }
michael@0:       if (!found) {
michael@0:         BPLOG(INFO) << "Couldn't load symbols for: "
michael@0:                     << frame->module->debug_file() << "|"
michael@0:                     << frame->module->debug_identifier();
michael@0:         modules_without_symbols->push_back(frame->module);
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     // Keep track of the number of dubious frames so far.
michael@0:     switch (frame.get()->trust) {
michael@0:        case StackFrame::FRAME_TRUST_NONE:
michael@0:        case StackFrame::FRAME_TRUST_SCAN:
michael@0:        case StackFrame::FRAME_TRUST_CFI_SCAN:
michael@0:          n_scanned_frames++;
michael@0:          break;
michael@0:       default:
michael@0:         break;
michael@0:     }
michael@0: 
michael@0:     // Add the frame to the call stack.  Relinquish the ownership claim
michael@0:     // over the frame, because the stack now owns it.
michael@0:     stack->frames_.push_back(frame.release());
michael@0:     if (stack->frames_.size() > max_frames_) {
michael@0:       // Only emit an error message in the case where the limit that we
michael@0:       // reached is the default limit, not set by the user.
michael@0:       if (!max_frames_set_)
michael@0:         BPLOG(ERROR) << "The stack is over " << max_frames_ << " frames.";
michael@0:       break;
michael@0:     }
michael@0: 
michael@0:     // Get the next frame and take ownership.
michael@0:     bool stack_scan_allowed = n_scanned_frames < max_frames_scanned_;
michael@0:     frame.reset(GetCallerFrame(stack, stack_scan_allowed));
michael@0:   }
michael@0: 
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: 
michael@0: // static
michael@0: Stackwalker* Stackwalker::StackwalkerForCPU(
michael@0:     const SystemInfo* system_info,
michael@0:     MinidumpContext* context,
michael@0:     MemoryRegion* memory,
michael@0:     const CodeModules* modules,
michael@0:     StackFrameSymbolizer* frame_symbolizer) {
michael@0:   if (!context) {
michael@0:     BPLOG(ERROR) << "Can't choose a stackwalker implementation without context";
michael@0:     return NULL;
michael@0:   }
michael@0: 
michael@0:   Stackwalker* cpu_stackwalker = NULL;
michael@0: 
michael@0:   uint32_t cpu = context->GetContextCPU();
michael@0:   switch (cpu) {
michael@0:     case MD_CONTEXT_X86:
michael@0:       cpu_stackwalker = new StackwalkerX86(system_info,
michael@0:                                            context->GetContextX86(),
michael@0:                                            memory, modules, frame_symbolizer);
michael@0:       break;
michael@0: 
michael@0:     case MD_CONTEXT_PPC:
michael@0:       cpu_stackwalker = new StackwalkerPPC(system_info,
michael@0:                                            context->GetContextPPC(),
michael@0:                                            memory, modules, frame_symbolizer);
michael@0:       break;
michael@0: 
michael@0:     case MD_CONTEXT_AMD64:
michael@0:       cpu_stackwalker = new StackwalkerAMD64(system_info,
michael@0:                                              context->GetContextAMD64(),
michael@0:                                              memory, modules, frame_symbolizer);
michael@0:       break;
michael@0: 
michael@0:     case MD_CONTEXT_SPARC:
michael@0:       cpu_stackwalker = new StackwalkerSPARC(system_info,
michael@0:                                              context->GetContextSPARC(),
michael@0:                                              memory, modules, frame_symbolizer);
michael@0:       break;
michael@0: 
michael@0:     case MD_CONTEXT_ARM:
michael@0:       int fp_register = -1;
michael@0:       if (system_info->os_short == "ios")
michael@0:         fp_register = MD_CONTEXT_ARM_REG_IOS_FP;
michael@0:       cpu_stackwalker = new StackwalkerARM(system_info,
michael@0:                                            context->GetContextARM(),
michael@0:                                            fp_register, memory, modules,
michael@0:                                            frame_symbolizer);
michael@0:       break;
michael@0:   }
michael@0: 
michael@0:   BPLOG_IF(ERROR, !cpu_stackwalker) << "Unknown CPU type " << HexString(cpu) <<
michael@0:                                        ", can't choose a stackwalker "
michael@0:                                        "implementation";
michael@0:   return cpu_stackwalker;
michael@0: }
michael@0: 
michael@0: bool Stackwalker::InstructionAddressSeemsValid(uint64_t address) {
michael@0:   StackFrame frame;
michael@0:   frame.instruction = address;
michael@0:   StackFrameSymbolizer::SymbolizerResult symbolizer_result =
michael@0:       frame_symbolizer_->FillSourceLineInfo(modules_, system_info_, &frame);
michael@0: 
michael@0:   if (!frame.module) {
michael@0:     // not inside any loaded module
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   if (!frame_symbolizer_->HasImplementation()) {
michael@0:     // No valid implementation to symbolize stack frame, but the address is
michael@0:     // within a known module.
michael@0:     return true;
michael@0:   }
michael@0: 
michael@0:   if (symbolizer_result != StackFrameSymbolizer::kNoError) {
michael@0:     // Some error occurred during symbolization, but the address is within a
michael@0:     // known module
michael@0:     return true;
michael@0:   }
michael@0: 
michael@0:   return !frame.function_name.empty();
michael@0: }
michael@0: 
michael@0: }  // namespace google_breakpad