diff options
Diffstat (limited to 'src/symbolize.h')
| -rw-r--r-- | src/symbolize.h | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/src/symbolize.h b/src/symbolize.h new file mode 100644 index 0000000000..c6f9ec4360 --- /dev/null +++ b/src/symbolize.h @@ -0,0 +1,158 @@ +// 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 +// +// This library provides Symbolize() function that symbolizes program +// counters to their corresponding symbol names on linux platforms. +// This library has a minimal implementation of an ELF symbol table +// reader (i.e. it doesn't depend on libelf, etc.). +// +// The algorithm used in Symbolize() is as follows. +// +// 1. Go through a list of maps in /proc/self/maps and find the map +// containing the program counter. +// +// 2. Open the mapped file and find a regular symbol table inside. +// Iterate over symbols in the symbol table and look for the symbol +// containing the program counter. If such a symbol is found, +// obtain the symbol name, and demangle the symbol if possible. +// If the symbol isn't found in the regular symbol table (binary is +// stripped), try the same thing with a dynamic symbol table. +// +// Note that Symbolize() is originally implemented to be used in +// FailureSignalHandler() in base/google.cc. Hence it doesn't use +// malloc() and other unsafe operations. It should be both +// thread-safe and async-signal-safe. + +#ifndef BASE_SYMBOLIZE_H_ +#define BASE_SYMBOLIZE_H_ + +#include "utilities.h" +#include "config.h" +#include "glog/logging.h" + +#ifdef HAVE_SYMBOLIZE + +#if defined(__ELF__) // defined by gcc +#if defined(__OpenBSD__) +#include <sys/exec_elf.h> +#else +#include <elf.h> +#endif + +#if !defined(ANDROID) +#include <link.h> // For ElfW() macro. +#endif + +// For systems where SIZEOF_VOID_P is not defined, determine it +// based on __LP64__ (defined by gcc on 64-bit systems) +#if !defined(SIZEOF_VOID_P) +# if defined(__LP64__) +# define SIZEOF_VOID_P 8 +# else +# define SIZEOF_VOID_P 4 +# endif +#endif + +// If there is no ElfW macro, let's define it by ourself. +#ifndef ElfW +# if SIZEOF_VOID_P == 4 +# define ElfW(type) Elf32_##type +# elif SIZEOF_VOID_P == 8 +# define ElfW(type) Elf64_##type +# else +# error "Unknown sizeof(void *)" +# endif +#endif + +_START_GOOGLE_NAMESPACE_ + +// Gets the section header for the given name, if it exists. Returns true on +// success. Otherwise, returns false. +bool GetSectionHeaderByName(int fd, const char *name, size_t name_len, + ElfW(Shdr) *out); + +_END_GOOGLE_NAMESPACE_ + +#endif /* __ELF__ */ + +_START_GOOGLE_NAMESPACE_ + +// Restrictions on the callbacks that follow: +// - The callbacks must not use heaps but only use stacks. +// - The callbacks must be async-signal-safe. + +// Installs a callback function, which will be called right before a symbol name +// is printed. The callback is intended to be used for showing a file name and a +// line number preceding a symbol name. +// "fd" is a file descriptor of the object file containing the program +// counter "pc". The callback function should write output to "out" +// and return the size of the output written. On error, the callback +// function should return -1. +typedef int (*SymbolizeCallback)(int fd, + void* pc, + char* out, + size_t out_size, + uint64_t relocation); +void InstallSymbolizeCallback(SymbolizeCallback callback); + +// Installs a callback function, which will be called instead of +// OpenObjectFileContainingPcAndGetStartAddress. The callback is expected +// to searches for the object file (from /proc/self/maps) that contains +// the specified pc. If found, sets |start_address| to the start address +// of where this object file is mapped in memory, sets the module base +// address into |base_address|, copies the object file name into +// |out_file_name|, and attempts to open the object file. If the object +// file is opened successfully, returns the file descriptor. Otherwise, +// returns -1. |out_file_name_size| is the size of the file name buffer +// (including the null-terminator). +typedef int (*SymbolizeOpenObjectFileCallback)(uint64_t pc, + uint64_t& start_address, + uint64_t& base_address, + char* out_file_name, + int out_file_name_size); +void InstallSymbolizeOpenObjectFileCallback( + SymbolizeOpenObjectFileCallback callback); + +_END_GOOGLE_NAMESPACE_ + +#endif + +_START_GOOGLE_NAMESPACE_ + +// Symbolizes a program counter. On success, returns true and write the +// symbol name to "out". The symbol name is demangled if possible +// (supports symbols generated by GCC 3.x or newer). Otherwise, +// returns false. +GOOGLE_GLOG_DLL_DECL bool Symbolize(void *pc, char *out, int out_size); + +_END_GOOGLE_NAMESPACE_ + +#endif // BASE_SYMBOLIZE_H_ |