The Tor Browser: toolkit/crashreporter/google-breakpad/src/processor/stackwalker

toolkit/crashreporter/google-breakpad/src/processor/stackwalker_selftest.cc@b8a032363ba2 (annotated)

toolkit/crashreporter/google-breakpad/src/processor/stackwalker_selftest.cc

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 // Copyright (c) 2006, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 // copyright notice, this list of conditions and the following disclaimer
 // in the documentation and/or other materials provided with the
 // distribution.
 //     * Neither the name of Google Inc. nor the names of its
 // contributors may be used to endorse or promote products derived from
 // this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 // stackwalker_selftest.cc: Tests StackwalkerX86 or StackwalkerPPC using the
 // running process' stack as test data, if running on an x86 or ppc and
 // compiled with gcc.  This test is not enabled in the "make check" suite
 // by default, because certain optimizations interfere with its proper
 // operation.  To turn it on, configure with --enable-selftest.
 //
 // Optimizations that cause problems:
 //  - stack frame reuse.  The Recursor function here calls itself with
 //    |return Recursor|.  When the caller's frame is reused, it will cause
 //    CountCallerFrames to correctly return the same number of frames
 //    in both the caller and callee.  This is considered an unexpected
 //    condition in the test, which expects a callee to have one more
 //    caller frame in the stack than its caller.
 //  - frame pointer omission.  Even with a stackwalker that understands
 //    this optimization, the code to harness debug information currently
 //    only exists to retrieve it from minidumps, not the current process.
 //
 // This test can also serve as a developmental and debugging aid if
 // PRINT_STACKS is defined.
 //
 // Author: Mark Mentovai
 #include "processor/logging.h"
 #if defined(__i386) && !defined(__i386__)
 #define __i386__
 #endif
 #if defined(__sparc) && !defined(__sparc__)
 #define __sparc__
 #endif
 #if (defined(__SUNPRO_CC) || defined(__GNUC__)) && \
     (defined(__i386__) || defined(__ppc__) || defined(__sparc__))
 #include <stdio.h>
 #include "common/scoped_ptr.h"
 #include "google_breakpad/common/breakpad_types.h"
 #include "google_breakpad/common/minidump_format.h"
 #include "google_breakpad/processor/basic_source_line_resolver.h"
 #include "google_breakpad/processor/call_stack.h"
 #include "google_breakpad/processor/code_module.h"
 #include "google_breakpad/processor/memory_region.h"
 #include "google_breakpad/processor/stack_frame.h"
 #include "google_breakpad/processor/stack_frame_cpu.h"
 using google_breakpad::BasicSourceLineResolver;
 using google_breakpad::CallStack;
 using google_breakpad::CodeModule;
 using google_breakpad::MemoryRegion;
 using google_breakpad::scoped_ptr;
 using google_breakpad::StackFrame;
 using google_breakpad::StackFramePPC;
 using google_breakpad::StackFrameX86;
 using google_breakpad::StackFrameSPARC;
 #if defined(__i386__)
 #include "processor/stackwalker_x86.h"
 using google_breakpad::StackwalkerX86;
 #elif defined(__ppc__)
 #include "processor/stackwalker_ppc.h"
 using google_breakpad::StackwalkerPPC;
 #elif defined(__sparc__)
 #include "processor/stackwalker_sparc.h"
 using google_breakpad::StackwalkerSPARC;
 #endif  // __i386__ || __ppc__ || __sparc__
 #define RECURSION_DEPTH 100
 // A simple MemoryRegion subclass that provides direct access to this
 // process' memory space by pointer.
 class SelfMemoryRegion : public MemoryRegion {
  public:
   virtual uint64_t GetBase() { return 0; }
   virtual uint32_t GetSize() { return 0xffffffff; }
   bool GetMemoryAtAddress(uint64_t address, uint8_t*  value) {
       return GetMemoryAtAddressInternal(address, value); }
   bool GetMemoryAtAddress(uint64_t address, uint16_t* value) {
       return GetMemoryAtAddressInternal(address, value); }
   bool GetMemoryAtAddress(uint64_t address, uint32_t* value) {
       return GetMemoryAtAddressInternal(address, value); }
   bool GetMemoryAtAddress(uint64_t address, uint64_t* value) {
       return GetMemoryAtAddressInternal(address, value); }
  private:
   template<typename T> bool GetMemoryAtAddressInternal(uint64_t address,
                                                        T*        value) {
     // Without knowing what addresses are actually mapped, just assume that
     // everything low is not mapped.  This helps the stackwalker catch the
     // end of a stack when it tries to dereference a null or low pointer
     // in an attempt to find the caller frame.  Other unmapped accesses will
     // cause the program to crash, but that would properly be a test failure.
     if (address < 0x100)
       return false;
     uint8_t* memory = 0;
     *value = *reinterpret_cast<const T*>(&memory[address]);
     return true;
   }
 };
 #if defined(__GNUC__)
 #if defined(__i386__)
 // GetEBP returns the current value of the %ebp register.  Because it's
 // implemented as a function, %ebp itself contains GetEBP's frame pointer
 // and not the caller's frame pointer.  Dereference %ebp to obtain the
 // caller's frame pointer, which the compiler-generated preamble stored
 // on the stack (provided frame pointers are not being omitted.)  Because
 // this function depends on the compiler-generated preamble, inlining is
 // disabled.
 static uint32_t GetEBP() __attribute__((noinline));
 static uint32_t GetEBP() {
   uint32_t ebp;
   __asm__ __volatile__(
     "movl (%%ebp), %0"
     : "=a" (ebp)
   );
   return ebp;
 }
 // The caller's %esp is 8 higher than the value of %ebp in this function,
 // assuming that it's not inlined and that the standard prolog is used.
 // The CALL instruction places a 4-byte return address on the stack above
 // the caller's %esp, and this function's prolog will save the caller's %ebp
 // on the stack as well, for another 4 bytes, before storing %esp in %ebp.
 static uint32_t GetESP() __attribute__((noinline));
 static uint32_t GetESP() {
   uint32_t ebp;
   __asm__ __volatile__(
     "movl %%ebp, %0"
     : "=a" (ebp)
   );
   return ebp + 8;
 }
 // GetEIP returns the instruction pointer identifying the next instruction
 // to execute after GetEIP returns.  It obtains this information from the
 // stack, where it was placed by the call instruction that called GetEIP.
 // This function depends on frame pointers not being omitted.  It is possible
 // to write a pure asm version of this routine that has no compiler-generated
 // preamble and uses %esp instead of %ebp; that would function in the
 // absence of frame pointers.  However, the simpler approach is used here
 // because GetEBP and stackwalking necessarily depends on access to frame
 // pointers.  Because this function depends on a call instruction and the
 // compiler-generated preamble, inlining is disabled.
 static uint32_t GetEIP() __attribute__((noinline));
 static uint32_t GetEIP() {
   uint32_t eip;
   __asm__ __volatile__(
     "movl 4(%%ebp), %0"
     : "=a" (eip)
   );
   return eip;
 }
 #elif defined(__ppc__)
 // GetSP returns the current value of the %r1 register, which by convention,
 // is the stack pointer on ppc.  Because it's implemented as a function,
 // %r1 itself contains GetSP's own stack pointer and not the caller's stack
 // pointer.  Dereference %r1 to obtain the caller's stack pointer, which the
 // compiler-generated prolog stored on the stack.  Because this function
 // depends on the compiler-generated prolog, inlining is disabled.
 static uint32_t GetSP() __attribute__((noinline));
 static uint32_t GetSP() {
   uint32_t sp;
   __asm__ __volatile__(
     "lwz %0, 0(r1)"
     : "=r" (sp)
   );
   return sp;
 }
 // GetPC returns the program counter identifying the next instruction to
 // execute after GetPC returns.  It obtains this information from the
 // link register, where it was placed by the branch instruction that called
 // GetPC.  Because this function depends on the caller's use of a branch
 // instruction, inlining is disabled.
 static uint32_t GetPC() __attribute__((noinline));
 static uint32_t GetPC() {
   uint32_t lr;
   __asm__ __volatile__(
     "mflr %0"
     : "=r" (lr)
   );
   return lr;
 }
 #elif defined(__sparc__)
 // GetSP returns the current value of the %sp/%o6/%g_r[14] register, which
 // by convention, is the stack pointer on sparc.  Because it's implemented
 // as a function, %sp itself contains GetSP's own stack pointer and not
 // the caller's stack pointer.  Dereference  to obtain the caller's stack
 // pointer, which the compiler-generated prolog stored on the stack.
 // Because this function depends on the compiler-generated prolog, inlining
 // is disabled.
 static uint32_t GetSP() __attribute__((noinline));
 static uint32_t GetSP() {
   uint32_t sp;
   __asm__ __volatile__(
     "mov %%fp, %0"
     : "=r" (sp)
   );
   return sp;
 }
 // GetFP returns the current value of the %fp register.  Because it's
 // implemented as a function, %fp itself contains GetFP's frame pointer
 // and not the caller's frame pointer.  Dereference %fp to obtain the
 // caller's frame pointer, which the compiler-generated preamble stored
 // on the stack (provided frame pointers are not being omitted.)  Because
 // this function depends on the compiler-generated preamble, inlining is
 // disabled.
 static uint32_t GetFP() __attribute__((noinline));
 static uint32_t GetFP() {
   uint32_t fp;
   __asm__ __volatile__(
     "ld [%%fp+56], %0"
     : "=r" (fp)
   );
   return fp;
 }
 // GetPC returns the program counter identifying the next instruction to
 // execute after GetPC returns.  It obtains this information from the
 // link register, where it was placed by the branch instruction that called
 // GetPC.  Because this function depends on the caller's use of a branch
 // instruction, inlining is disabled.
 static uint32_t GetPC() __attribute__((noinline));
 static uint32_t GetPC() {
   uint32_t pc;
   __asm__ __volatile__(
     "mov %%i7, %0"
     : "=r" (pc)
   );
   return pc + 8;
 }
 #endif  // __i386__ || __ppc__ || __sparc__
 #elif defined(__SUNPRO_CC)
 #if defined(__i386__)
 extern "C" {
 extern uint32_t GetEIP();
 extern uint32_t GetEBP();
 extern uint32_t GetESP();
 }
 #elif defined(__sparc__)
 extern "C" {
 extern uint32_t GetPC();
 extern uint32_t GetFP();
 extern uint32_t GetSP();
 }
 #endif // __i386__ || __sparc__
 #endif // __GNUC__ || __SUNPRO_CC
 // CountCallerFrames returns the number of stack frames beneath the function
 // that called CountCallerFrames.  Because this function's return value
 // is dependent on the size of the stack beneath it, inlining is disabled,
 // and any function that calls this should not be inlined either.
 #if defined(__GNUC__)
 static unsigned int CountCallerFrames() __attribute__((noinline));
 #elif defined(__SUNPRO_CC)
 static unsigned int CountCallerFrames();
 #endif
 static unsigned int CountCallerFrames() {
   SelfMemoryRegion memory;
   BasicSourceLineResolver resolver;
 #if defined(__i386__)
   MDRawContextX86 context = MDRawContextX86();
   context.eip = GetEIP();
   context.ebp = GetEBP();
   context.esp = GetESP();
   StackwalkerX86 stackwalker = StackwalkerX86(NULL, &context, &memory, NULL,
                                               NULL, &resolver);
 #elif defined(__ppc__)
   MDRawContextPPC context = MDRawContextPPC();
   context.srr0 = GetPC();
   context.gpr[1] = GetSP();
   StackwalkerPPC stackwalker = StackwalkerPPC(NULL, &context, &memory, NULL,
                                               NULL, &resolver);
 #elif defined(__sparc__)
   MDRawContextSPARC context = MDRawContextSPARC();
   context.pc = GetPC();
   context.g_r[14] = GetSP();
   context.g_r[30] = GetFP();
   StackwalkerSPARC stackwalker = StackwalkerSPARC(NULL, &context, &memory,
                                                   NULL, NULL, &resolver);
 #endif  // __i386__ || __ppc__ || __sparc__
   CallStack stack;
   vector<const CodeModule*> modules_without_symbols;
   stackwalker.Walk(&stack, &modules_without_symbols);
 #ifdef PRINT_STACKS
   printf("\n");
   for (unsigned int frame_index = 0;
       frame_index < stack.frames()->size();
       ++frame_index) {
     StackFrame *frame = stack.frames()->at(frame_index);
     printf("frame %-3d  instruction = 0x%08" PRIx64,
            frame_index, frame->instruction);
 #if defined(__i386__)
     StackFrameX86 *frame_x86 = reinterpret_cast<StackFrameX86*>(frame);
     printf("  esp = 0x%08x  ebp = 0x%08x\n",
            frame_x86->context.esp, frame_x86->context.ebp);
 #elif defined(__ppc__)
     StackFramePPC *frame_ppc = reinterpret_cast<StackFramePPC*>(frame);
     printf("  gpr[1] = 0x%08x\n", frame_ppc->context.gpr[1]);
 #elif defined(__sparc__)
     StackFrameSPARC *frame_sparc = reinterpret_cast<StackFrameSPARC*>(frame);
     printf("  sp = 0x%08x  fp = 0x%08x\n",
            frame_sparc->context.g_r[14], frame_sparc->context.g_r[30]);
 #endif  // __i386__ || __ppc__ || __sparc__
   }
 #endif  // PRINT_STACKS
   // Subtract 1 because the caller wants the number of frames beneath
   // itself.  Because the caller called us, subract two for our frame and its
   // frame, which are included in stack.size().
   return stack.frames()->size() - 2;
 }
 // Recursor verifies that the number stack frames beneath itself is one more
 // than the number of stack frames beneath its parent.  When depth frames
 // have been reached, Recursor stops checking and returns success.  If the
 // frame count check fails at any depth, Recursor will stop and return false.
 // Because this calls CountCallerFrames, inlining is disabled.
 #if defined(__GNUC__)
 static bool Recursor(unsigned int depth, unsigned int parent_callers)
     __attribute__((noinline));
 #elif defined(__SUNPRO_CC)
 static bool Recursor(unsigned int depth, unsigned int parent_callers);
 #endif
 static bool Recursor(unsigned int depth, unsigned int parent_callers) {
   unsigned int callers = CountCallerFrames();
   if (callers != parent_callers + 1)
     return false;
   if (depth)
     return Recursor(depth - 1, callers);
   // depth == 0
   return true;
 }
 // Because this calls CountCallerFrames, inlining is disabled - but because
 // it's main (and nobody calls it other than the entry point), it wouldn't
 // be inlined anyway.
 #if defined(__GNUC__)
 int main(int argc, char** argv) __attribute__((noinline));
 #elif defined(__SUNPRO_CC)
 int main(int argc, char** argv);
 #endif
 int main(int argc, char** argv) {
   BPLOG_INIT(&argc, &argv);
   return Recursor(RECURSION_DEPTH, CountCallerFrames()) ? 0 : 1;
 }
 #else
 // Not i386 or ppc or sparc?  We can only test stacks we know how to walk.
 int main(int argc, char **argv) {
   BPLOG_INIT(&argc, &argv);
   // "make check" interprets an exit status of 77 to mean that the test is
   // not supported.
   BPLOG(ERROR) << "Selftest not supported here";
   return 77;
 }
 #endif  // (__GNUC__ || __SUNPRO_CC) && (__i386__ || __ppc__ || __sparc__)

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toolkit/crashreporter/google-breakpad/src/processor/stackwalker_selftest.cc@b8a032363ba2 (annotated)

toolkit/crashreporter/google-breakpad/src/processor/stackwalker_selftest.cc