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Diffstat (limited to 'src/symbolize_unittest.cc')
| -rw-r--r-- | src/symbolize_unittest.cc | 425 |
1 files changed, 425 insertions, 0 deletions
diff --git a/src/symbolize_unittest.cc b/src/symbolize_unittest.cc new file mode 100644 index 000000000000..35cc2d31ff9b --- /dev/null +++ b/src/symbolize_unittest.cc @@ -0,0 +1,425 @@ +// 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. +// +// Author: Satoru Takabayashi +// +// Unit tests for functions in symbolize.cc. + +#include "utilities.h" + +#include <signal.h> +#include <iostream> + +#include "glog/logging.h" +#include "symbolize.h" +#include "googletest.h" +#include "config.h" + +#ifdef HAVE_LIB_GFLAGS +#include <gflags/gflags.h> +using namespace GFLAGS_NAMESPACE; +#endif + +using namespace std; +using namespace GOOGLE_NAMESPACE; + +#if defined(HAVE_STACKTRACE) + +#define always_inline + +// A wrapper function for Symbolize() to make the unit test simple. +static const char *TrySymbolize(void *pc) { + static char symbol[4096]; + if (Symbolize(pc, symbol, sizeof(symbol))) { + return symbol; + } else { + return NULL; + } +} + +# if defined(__ELF__) + +// This unit tests make sense only with GCC. +// Uses lots of GCC specific features. +#if defined(__GNUC__) && !defined(__OPENCC__) +# if __GNUC__ >= 4 +# define TEST_WITH_MODERN_GCC +# if __i386__ // always_inline isn't supported for x86_64 with GCC 4.1.0. +# undef always_inline +# define always_inline __attribute__((always_inline)) +# define HAVE_ALWAYS_INLINE +# endif // __i386__ +# else +# endif // __GNUC__ >= 4 +# if defined(__i386__) || defined(__x86_64__) +# define TEST_X86_32_AND_64 1 +# endif // defined(__i386__) || defined(__x86_64__) +#endif + +// Make them C linkage to avoid mangled names. +extern "C" { +void nonstatic_func(); +void nonstatic_func() { + volatile int a = 0; + ++a; +} + +static void static_func() { + volatile int a = 0; + ++a; +} +} + +TEST(Symbolize, Symbolize) { + // We do C-style cast since GCC 2.95.3 doesn't allow + // reinterpret_cast<void *>(&func). + + // Compilers should give us pointers to them. + EXPECT_STREQ("nonstatic_func", TrySymbolize((void *)(&nonstatic_func))); + + // The name of an internal linkage symbol is not specified; allow either a + // mangled or an unmangled name here. + const char *static_func_symbol = TrySymbolize((void *)(&static_func)); + CHECK(NULL != static_func_symbol); + EXPECT_TRUE(strcmp("static_func", static_func_symbol) == 0 || + strcmp("static_func()", static_func_symbol) == 0); + + EXPECT_TRUE(NULL == TrySymbolize(NULL)); +} + +struct Foo { + static void func(int x); +}; + +void ATTRIBUTE_NOINLINE Foo::func(int x) { + volatile int a = x; + ++a; +} + +// With a modern GCC, Symbolize() should return demangled symbol +// names. Function parameters should be omitted. +#ifdef TEST_WITH_MODERN_GCC +TEST(Symbolize, SymbolizeWithDemangling) { + Foo::func(100); + EXPECT_STREQ("Foo::func()", TrySymbolize((void *)(&Foo::func))); +} +#endif + +// Tests that verify that Symbolize footprint is within some limit. + +// To measure the stack footprint of the Symbolize function, we create +// a signal handler (for SIGUSR1 say) that calls the Symbolize function +// on an alternate stack. This alternate stack is initialized to some +// known pattern (0x55, 0x55, 0x55, ...). We then self-send this signal, +// and after the signal handler returns, look at the alternate stack +// buffer to see what portion has been touched. +// +// This trick gives us the the stack footprint of the signal handler. +// But the signal handler, even before the call to Symbolize, consumes +// some stack already. We however only want the stack usage of the +// Symbolize function. To measure this accurately, we install two signal +// handlers: one that does nothing and just returns, and another that +// calls Symbolize. The difference between the stack consumption of these +// two signals handlers should give us the Symbolize stack foorprint. + +static void *g_pc_to_symbolize; +static char g_symbolize_buffer[4096]; +static char *g_symbolize_result; + +static void EmptySignalHandler(int signo) {} + +static void SymbolizeSignalHandler(int signo) { + if (Symbolize(g_pc_to_symbolize, g_symbolize_buffer, + sizeof(g_symbolize_buffer))) { + g_symbolize_result = g_symbolize_buffer; + } else { + g_symbolize_result = NULL; + } +} + +const int kAlternateStackSize = 8096; +const char kAlternateStackFillValue = 0x55; + +// These helper functions look at the alternate stack buffer, and figure +// out what portion of this buffer has been touched - this is the stack +// consumption of the signal handler running on this alternate stack. +static ATTRIBUTE_NOINLINE bool StackGrowsDown(int *x) { + int y; + return &y < x; +} +static int GetStackConsumption(const char* alt_stack) { + int x; + if (StackGrowsDown(&x)) { + for (int i = 0; i < kAlternateStackSize; i++) { + if (alt_stack[i] != kAlternateStackFillValue) { + return (kAlternateStackSize - i); + } + } + } else { + for (int i = (kAlternateStackSize - 1); i >= 0; i--) { + if (alt_stack[i] != kAlternateStackFillValue) { + return i; + } + } + } + return -1; +} + +#ifdef HAVE_SIGALTSTACK + +// Call Symbolize and figure out the stack footprint of this call. +static const char *SymbolizeStackConsumption(void *pc, int *stack_consumed) { + + g_pc_to_symbolize = pc; + + // The alt-signal-stack cannot be heap allocated because there is a + // bug in glibc-2.2 where some signal handler setup code looks at the + // current stack pointer to figure out what thread is currently running. + // Therefore, the alternate stack must be allocated from the main stack + // itself. + char altstack[kAlternateStackSize]; + memset(altstack, kAlternateStackFillValue, kAlternateStackSize); + + // Set up the alt-signal-stack (and save the older one). + stack_t sigstk; + memset(&sigstk, 0, sizeof(stack_t)); + stack_t old_sigstk; + sigstk.ss_sp = altstack; + sigstk.ss_size = kAlternateStackSize; + sigstk.ss_flags = 0; + CHECK_ERR(sigaltstack(&sigstk, &old_sigstk)); + + // Set up SIGUSR1 and SIGUSR2 signal handlers (and save the older ones). + struct sigaction sa; + memset(&sa, 0, sizeof(struct sigaction)); + struct sigaction old_sa1, old_sa2; + sigemptyset(&sa.sa_mask); + sa.sa_flags = SA_ONSTACK; + + // SIGUSR1 maps to EmptySignalHandler. + sa.sa_handler = EmptySignalHandler; + CHECK_ERR(sigaction(SIGUSR1, &sa, &old_sa1)); + + // SIGUSR2 maps to SymbolizeSignalHanlder. + sa.sa_handler = SymbolizeSignalHandler; + CHECK_ERR(sigaction(SIGUSR2, &sa, &old_sa2)); + + // Send SIGUSR1 signal and measure the stack consumption of the empty + // signal handler. + CHECK_ERR(kill(getpid(), SIGUSR1)); + int stack_consumption1 = GetStackConsumption(altstack); + + // Send SIGUSR2 signal and measure the stack consumption of the symbolize + // signal handler. + CHECK_ERR(kill(getpid(), SIGUSR2)); + int stack_consumption2 = GetStackConsumption(altstack); + + // The difference between the two stack consumption values is the + // stack footprint of the Symbolize function. + if (stack_consumption1 != -1 && stack_consumption2 != -1) { + *stack_consumed = stack_consumption2 - stack_consumption1; + } else { + *stack_consumed = -1; + } + + // Log the stack consumption values. + LOG(INFO) << "Stack consumption of empty signal handler: " + << stack_consumption1; + LOG(INFO) << "Stack consumption of symbolize signal handler: " + << stack_consumption2; + LOG(INFO) << "Stack consumption of Symbolize: " << *stack_consumed; + + // Now restore the old alt-signal-stack and signal handlers. + CHECK_ERR(sigaltstack(&old_sigstk, NULL)); + CHECK_ERR(sigaction(SIGUSR1, &old_sa1, NULL)); + CHECK_ERR(sigaction(SIGUSR2, &old_sa2, NULL)); + + return g_symbolize_result; +} + +#ifdef __ppc64__ +// Symbolize stack consumption should be within 4kB. +const int kStackConsumptionUpperLimit = 4096; +#else +// Symbolize stack consumption should be within 2kB. +const int kStackConsumptionUpperLimit = 2048; +#endif + +TEST(Symbolize, SymbolizeStackConsumption) { + int stack_consumed; + const char* symbol; + + symbol = SymbolizeStackConsumption((void *)(&nonstatic_func), + &stack_consumed); + EXPECT_STREQ("nonstatic_func", symbol); + EXPECT_GT(stack_consumed, 0); + EXPECT_LT(stack_consumed, kStackConsumptionUpperLimit); + + // The name of an internal linkage symbol is not specified; allow either a + // mangled or an unmangled name here. + symbol = SymbolizeStackConsumption((void *)(&static_func), + &stack_consumed); + CHECK(NULL != symbol); + EXPECT_TRUE(strcmp("static_func", symbol) == 0 || + strcmp("static_func()", symbol) == 0); + EXPECT_GT(stack_consumed, 0); + EXPECT_LT(stack_consumed, kStackConsumptionUpperLimit); +} + +#ifdef TEST_WITH_MODERN_GCC +TEST(Symbolize, SymbolizeWithDemanglingStackConsumption) { + Foo::func(100); + int stack_consumed; + const char* symbol; + + symbol = SymbolizeStackConsumption((void *)(&Foo::func), &stack_consumed); + + EXPECT_STREQ("Foo::func()", symbol); + EXPECT_GT(stack_consumed, 0); + EXPECT_LT(stack_consumed, kStackConsumptionUpperLimit); +} +#endif + +#endif // HAVE_SIGALTSTACK + +// x86 specific tests. Uses some inline assembler. +extern "C" { +inline void* always_inline inline_func() { + void *pc = NULL; +#ifdef TEST_X86_32_AND_64 + __asm__ __volatile__("call 1f; 1: pop %0" : "=r"(pc)); +#endif + return pc; +} + +void* ATTRIBUTE_NOINLINE non_inline_func(); +void* ATTRIBUTE_NOINLINE non_inline_func() { + void *pc = NULL; +#ifdef TEST_X86_32_AND_64 + __asm__ __volatile__("call 1f; 1: pop %0" : "=r"(pc)); +#endif + return pc; +} + +static void ATTRIBUTE_NOINLINE TestWithPCInsideNonInlineFunction() { +#if defined(TEST_X86_32_AND_64) && defined(HAVE_ATTRIBUTE_NOINLINE) + void *pc = non_inline_func(); + const char *symbol = TrySymbolize(pc); + CHECK(symbol != NULL); + CHECK_STREQ(symbol, "non_inline_func"); + cout << "Test case TestWithPCInsideNonInlineFunction passed." << endl; +#endif +} + +static void ATTRIBUTE_NOINLINE TestWithPCInsideInlineFunction() { +#if defined(TEST_X86_32_AND_64) && defined(HAVE_ALWAYS_INLINE) + void *pc = inline_func(); // Must be inlined. + const char *symbol = TrySymbolize(pc); + CHECK(symbol != NULL); + CHECK_STREQ(symbol, __FUNCTION__); + cout << "Test case TestWithPCInsideInlineFunction passed." << endl; +#endif +} +} + +// Test with a return address. +static void ATTRIBUTE_NOINLINE TestWithReturnAddress() { +#if defined(HAVE_ATTRIBUTE_NOINLINE) + void *return_address = __builtin_return_address(0); + const char *symbol = TrySymbolize(return_address); + CHECK(symbol != NULL); + CHECK_STREQ(symbol, "main"); + cout << "Test case TestWithReturnAddress passed." << endl; +#endif +} + +# elif defined(OS_WINDOWS) || defined(OS_CYGWIN) + +#ifdef _MSC_VER +#include <intrin.h> +#pragma intrinsic(_ReturnAddress) +#endif + +struct Foo { + static void func(int x); +}; + +__declspec(noinline) void Foo::func(int x) { + volatile int a = x; + ++a; +} + +TEST(Symbolize, SymbolizeWithDemangling) { + Foo::func(100); + const char* ret = TrySymbolize((void *)(&Foo::func)); + EXPECT_STREQ("public: static void __cdecl Foo::func(int)", ret); +} + +__declspec(noinline) void TestWithReturnAddress() { + void *return_address = +#ifdef __GNUC__ // Cygwin and MinGW support + __builtin_return_address(0) +#else + _ReturnAddress() +#endif + ; + const char *symbol = TrySymbolize(return_address); + CHECK(symbol != NULL); + CHECK_STREQ(symbol, "main"); + cout << "Test case TestWithReturnAddress passed." << endl; +} +# endif // __ELF__ +#endif // HAVE_STACKTRACE + +int main(int argc, char **argv) { + FLAGS_logtostderr = true; + InitGoogleLogging(argv[0]); + InitGoogleTest(&argc, argv); +#if defined(HAVE_SYMBOLIZE) && defined(HAVE_STACKTRACE) +# if defined(__ELF__) + // We don't want to get affected by the callback interface, that may be + // used to install some callback function at InitGoogle() time. + InstallSymbolizeCallback(NULL); + + TestWithPCInsideInlineFunction(); + TestWithPCInsideNonInlineFunction(); + TestWithReturnAddress(); + return RUN_ALL_TESTS(); +# elif defined(OS_WINDOWS) || defined(OS_CYGWIN) + TestWithReturnAddress(); + return RUN_ALL_TESTS(); +# else // OS_WINDOWS + printf("PASS (no symbolize_unittest support)\n"); + return 0; +# endif // __ELF__ +#else + printf("PASS (no symbolize support)\n"); + return 0; +#endif // HAVE_SYMBOLIZE +} |