| Index: base/third_party/symbolize/symbolize.cc
|
| diff --git a/base/third_party/symbolize/symbolize.cc b/base/third_party/symbolize/symbolize.cc
|
| deleted file mode 100644
|
| index f4861dfe523e7cd7e157603fddb4da6d513c688a..0000000000000000000000000000000000000000
|
| --- a/base/third_party/symbolize/symbolize.cc
|
| +++ /dev/null
|
| @@ -1,849 +0,0 @@
|
| -// 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
|
| -// Stack-footprint reduction work done by Raksit Ashok
|
| -//
|
| -// Implementation note:
|
| -//
|
| -// We don't use heaps but only use stacks. We want to reduce the
|
| -// stack consumption so that the symbolizer can run on small stacks.
|
| -//
|
| -// Here are some numbers collected with GCC 4.1.0 on x86:
|
| -// - sizeof(Elf32_Sym) = 16
|
| -// - sizeof(Elf32_Shdr) = 40
|
| -// - sizeof(Elf64_Sym) = 24
|
| -// - sizeof(Elf64_Shdr) = 64
|
| -//
|
| -// This implementation is intended to be async-signal-safe but uses
|
| -// some functions which are not guaranteed to be so, such as memchr()
|
| -// and memmove(). We assume they are async-signal-safe.
|
| -//
|
| -// Additional header can be specified by the GLOG_BUILD_CONFIG_INCLUDE
|
| -// macro to add platform specific defines (e.g. OS_OPENBSD).
|
| -
|
| -#ifdef GLOG_BUILD_CONFIG_INCLUDE
|
| -#include GLOG_BUILD_CONFIG_INCLUDE
|
| -#endif // GLOG_BUILD_CONFIG_INCLUDE
|
| -
|
| -#include "utilities.h"
|
| -
|
| -#if defined(HAVE_SYMBOLIZE)
|
| -
|
| -#include <limits>
|
| -
|
| -#include "symbolize.h"
|
| -#include "demangle.h"
|
| -
|
| -_START_GOOGLE_NAMESPACE_
|
| -
|
| -// We don't use assert() since it's not guaranteed to be
|
| -// async-signal-safe. Instead we define a minimal assertion
|
| -// macro. So far, we don't need pretty printing for __FILE__, etc.
|
| -
|
| -// A wrapper for abort() to make it callable in ? :.
|
| -static int AssertFail() {
|
| - abort();
|
| - return 0; // Should not reach.
|
| -}
|
| -
|
| -#define SAFE_ASSERT(expr) ((expr) ? 0 : AssertFail())
|
| -
|
| -static SymbolizeCallback g_symbolize_callback = NULL;
|
| -void InstallSymbolizeCallback(SymbolizeCallback callback) {
|
| - g_symbolize_callback = callback;
|
| -}
|
| -
|
| -static SymbolizeOpenObjectFileCallback g_symbolize_open_object_file_callback =
|
| - NULL;
|
| -void InstallSymbolizeOpenObjectFileCallback(
|
| - SymbolizeOpenObjectFileCallback callback) {
|
| - g_symbolize_open_object_file_callback = callback;
|
| -}
|
| -
|
| -// This function wraps the Demangle function to provide an interface
|
| -// where the input symbol is demangled in-place.
|
| -// To keep stack consumption low, we would like this function to not
|
| -// get inlined.
|
| -static ATTRIBUTE_NOINLINE void DemangleInplace(char *out, int out_size) {
|
| - char demangled[256]; // Big enough for sane demangled symbols.
|
| - if (Demangle(out, demangled, sizeof(demangled))) {
|
| - // Demangling succeeded. Copy to out if the space allows.
|
| - size_t len = strlen(demangled);
|
| - if (len + 1 <= (size_t)out_size) { // +1 for '\0'.
|
| - SAFE_ASSERT(len < sizeof(demangled));
|
| - memmove(out, demangled, len + 1);
|
| - }
|
| - }
|
| -}
|
| -
|
| -_END_GOOGLE_NAMESPACE_
|
| -
|
| -#if defined(__ELF__)
|
| -
|
| -#include <dlfcn.h>
|
| -#if defined(OS_OPENBSD)
|
| -#include <sys/exec_elf.h>
|
| -#else
|
| -#include <elf.h>
|
| -#endif
|
| -#include <errno.h>
|
| -#include <fcntl.h>
|
| -#include <limits.h>
|
| -#include <stdint.h>
|
| -#include <stdio.h>
|
| -#include <stdlib.h>
|
| -#include <stddef.h>
|
| -#include <string.h>
|
| -#include <sys/stat.h>
|
| -#include <sys/types.h>
|
| -#include <unistd.h>
|
| -
|
| -#include "symbolize.h"
|
| -#include "config.h"
|
| -#include "glog/raw_logging.h"
|
| -
|
| -// Re-runs fn until it doesn't cause EINTR.
|
| -#define NO_INTR(fn) do {} while ((fn) < 0 && errno == EINTR)
|
| -
|
| -_START_GOOGLE_NAMESPACE_
|
| -
|
| -// Read up to "count" bytes from file descriptor "fd" into the buffer
|
| -// starting at "buf" while handling short reads and EINTR. On
|
| -// success, return the number of bytes read. Otherwise, return -1.
|
| -static ssize_t ReadPersistent(const int fd, void *buf, const size_t count) {
|
| - SAFE_ASSERT(fd >= 0);
|
| - SAFE_ASSERT(count <= std::numeric_limits<ssize_t>::max());
|
| - char *buf0 = reinterpret_cast<char *>(buf);
|
| - ssize_t num_bytes = 0;
|
| - while (num_bytes < count) {
|
| - ssize_t len;
|
| - NO_INTR(len = read(fd, buf0 + num_bytes, count - num_bytes));
|
| - if (len < 0) { // There was an error other than EINTR.
|
| - return -1;
|
| - }
|
| - if (len == 0) { // Reached EOF.
|
| - break;
|
| - }
|
| - num_bytes += len;
|
| - }
|
| - SAFE_ASSERT(num_bytes <= count);
|
| - return num_bytes;
|
| -}
|
| -
|
| -// Read up to "count" bytes from "offset" in the file pointed by file
|
| -// descriptor "fd" into the buffer starting at "buf". On success,
|
| -// return the number of bytes read. Otherwise, return -1.
|
| -static ssize_t ReadFromOffset(const int fd, void *buf,
|
| - const size_t count, const off_t offset) {
|
| - off_t off = lseek(fd, offset, SEEK_SET);
|
| - if (off == (off_t)-1) {
|
| - return -1;
|
| - }
|
| - return ReadPersistent(fd, buf, count);
|
| -}
|
| -
|
| -// Try reading exactly "count" bytes from "offset" bytes in a file
|
| -// pointed by "fd" into the buffer starting at "buf" while handling
|
| -// short reads and EINTR. On success, return true. Otherwise, return
|
| -// false.
|
| -static bool ReadFromOffsetExact(const int fd, void *buf,
|
| - const size_t count, const off_t offset) {
|
| - ssize_t len = ReadFromOffset(fd, buf, count, offset);
|
| - return len == count;
|
| -}
|
| -
|
| -// Returns elf_header.e_type if the file pointed by fd is an ELF binary.
|
| -static int FileGetElfType(const int fd) {
|
| - ElfW(Ehdr) elf_header;
|
| - if (!ReadFromOffsetExact(fd, &elf_header, sizeof(elf_header), 0)) {
|
| - return -1;
|
| - }
|
| - if (memcmp(elf_header.e_ident, ELFMAG, SELFMAG) != 0) {
|
| - return -1;
|
| - }
|
| - return elf_header.e_type;
|
| -}
|
| -
|
| -// Read the section headers in the given ELF binary, and if a section
|
| -// of the specified type is found, set the output to this section header
|
| -// and return true. Otherwise, return false.
|
| -// To keep stack consumption low, we would like this function to not get
|
| -// inlined.
|
| -static ATTRIBUTE_NOINLINE bool
|
| -GetSectionHeaderByType(const int fd, ElfW(Half) sh_num, const off_t sh_offset,
|
| - ElfW(Word) type, ElfW(Shdr) *out) {
|
| - // Read at most 16 section headers at a time to save read calls.
|
| - ElfW(Shdr) buf[16];
|
| - for (int i = 0; i < sh_num;) {
|
| - const ssize_t num_bytes_left = (sh_num - i) * sizeof(buf[0]);
|
| - const ssize_t num_bytes_to_read =
|
| - (sizeof(buf) > num_bytes_left) ? num_bytes_left : sizeof(buf);
|
| - const ssize_t len = ReadFromOffset(fd, buf, num_bytes_to_read,
|
| - sh_offset + i * sizeof(buf[0]));
|
| - SAFE_ASSERT(len % sizeof(buf[0]) == 0);
|
| - const ssize_t num_headers_in_buf = len / sizeof(buf[0]);
|
| - SAFE_ASSERT(num_headers_in_buf <= sizeof(buf) / sizeof(buf[0]));
|
| - for (int j = 0; j < num_headers_in_buf; ++j) {
|
| - if (buf[j].sh_type == type) {
|
| - *out = buf[j];
|
| - return true;
|
| - }
|
| - }
|
| - i += num_headers_in_buf;
|
| - }
|
| - return false;
|
| -}
|
| -
|
| -// There is no particular reason to limit section name to 63 characters,
|
| -// but there has (as yet) been no need for anything longer either.
|
| -const int kMaxSectionNameLen = 64;
|
| -
|
| -// name_len should include terminating '\0'.
|
| -bool GetSectionHeaderByName(int fd, const char *name, size_t name_len,
|
| - ElfW(Shdr) *out) {
|
| - ElfW(Ehdr) elf_header;
|
| - if (!ReadFromOffsetExact(fd, &elf_header, sizeof(elf_header), 0)) {
|
| - return false;
|
| - }
|
| -
|
| - ElfW(Shdr) shstrtab;
|
| - off_t shstrtab_offset = (elf_header.e_shoff +
|
| - elf_header.e_shentsize * elf_header.e_shstrndx);
|
| - if (!ReadFromOffsetExact(fd, &shstrtab, sizeof(shstrtab), shstrtab_offset)) {
|
| - return false;
|
| - }
|
| -
|
| - for (int i = 0; i < elf_header.e_shnum; ++i) {
|
| - off_t section_header_offset = (elf_header.e_shoff +
|
| - elf_header.e_shentsize * i);
|
| - if (!ReadFromOffsetExact(fd, out, sizeof(*out), section_header_offset)) {
|
| - return false;
|
| - }
|
| - char header_name[kMaxSectionNameLen];
|
| - if (sizeof(header_name) < name_len) {
|
| - RAW_LOG(WARNING, "Section name '%s' is too long (%" PRIuS "); "
|
| - "section will not be found (even if present).", name, name_len);
|
| - // No point in even trying.
|
| - return false;
|
| - }
|
| - off_t name_offset = shstrtab.sh_offset + out->sh_name;
|
| - ssize_t n_read = ReadFromOffset(fd, &header_name, name_len, name_offset);
|
| - if (n_read == -1) {
|
| - return false;
|
| - } else if (n_read != name_len) {
|
| - // Short read -- name could be at end of file.
|
| - continue;
|
| - }
|
| - if (memcmp(header_name, name, name_len) == 0) {
|
| - return true;
|
| - }
|
| - }
|
| - return false;
|
| -}
|
| -
|
| -// Read a symbol table and look for the symbol containing the
|
| -// pc. Iterate over symbols in a symbol table and look for the symbol
|
| -// containing "pc". On success, return true and write the symbol name
|
| -// to out. Otherwise, return false.
|
| -// To keep stack consumption low, we would like this function to not get
|
| -// inlined.
|
| -static ATTRIBUTE_NOINLINE bool
|
| -FindSymbol(uint64_t pc, const int fd, char *out, int out_size,
|
| - uint64_t symbol_offset, const ElfW(Shdr) *strtab,
|
| - const ElfW(Shdr) *symtab) {
|
| - if (symtab == NULL) {
|
| - return false;
|
| - }
|
| - const int num_symbols = symtab->sh_size / symtab->sh_entsize;
|
| - for (int i = 0; i < num_symbols;) {
|
| - off_t offset = symtab->sh_offset + i * symtab->sh_entsize;
|
| -
|
| - // If we are reading Elf64_Sym's, we want to limit this array to
|
| - // 32 elements (to keep stack consumption low), otherwise we can
|
| - // have a 64 element Elf32_Sym array.
|
| -#if __WORDSIZE == 64
|
| -#define NUM_SYMBOLS 32
|
| -#else
|
| -#define NUM_SYMBOLS 64
|
| -#endif
|
| -
|
| - // Read at most NUM_SYMBOLS symbols at once to save read() calls.
|
| - ElfW(Sym) buf[NUM_SYMBOLS];
|
| - const ssize_t len = ReadFromOffset(fd, &buf, sizeof(buf), offset);
|
| - SAFE_ASSERT(len % sizeof(buf[0]) == 0);
|
| - const ssize_t num_symbols_in_buf = len / sizeof(buf[0]);
|
| - SAFE_ASSERT(num_symbols_in_buf <= sizeof(buf)/sizeof(buf[0]));
|
| - for (int j = 0; j < num_symbols_in_buf; ++j) {
|
| - const ElfW(Sym)& symbol = buf[j];
|
| - uint64_t start_address = symbol.st_value;
|
| - start_address += symbol_offset;
|
| - uint64_t end_address = start_address + symbol.st_size;
|
| - if (symbol.st_value != 0 && // Skip null value symbols.
|
| - symbol.st_shndx != 0 && // Skip undefined symbols.
|
| - start_address <= pc && pc < end_address) {
|
| - ssize_t len1 = ReadFromOffset(fd, out, out_size,
|
| - strtab->sh_offset + symbol.st_name);
|
| - if (len1 <= 0 || memchr(out, '\0', out_size) == NULL) {
|
| - return false;
|
| - }
|
| - return true; // Obtained the symbol name.
|
| - }
|
| - }
|
| - i += num_symbols_in_buf;
|
| - }
|
| - return false;
|
| -}
|
| -
|
| -// Get the symbol name of "pc" from the file pointed by "fd". Process
|
| -// both regular and dynamic symbol tables if necessary. On success,
|
| -// write the symbol name to "out" and return true. Otherwise, return
|
| -// false.
|
| -static bool GetSymbolFromObjectFile(const int fd, uint64_t pc,
|
| - char *out, int out_size,
|
| - uint64_t map_start_address) {
|
| - // Read the ELF header.
|
| - ElfW(Ehdr) elf_header;
|
| - if (!ReadFromOffsetExact(fd, &elf_header, sizeof(elf_header), 0)) {
|
| - return false;
|
| - }
|
| -
|
| - uint64_t symbol_offset = 0;
|
| - if (elf_header.e_type == ET_DYN) { // DSO needs offset adjustment.
|
| - symbol_offset = map_start_address;
|
| - }
|
| -
|
| - ElfW(Shdr) symtab, strtab;
|
| -
|
| - // Consult a regular symbol table first.
|
| - if (GetSectionHeaderByType(fd, elf_header.e_shnum, elf_header.e_shoff,
|
| - SHT_SYMTAB, &symtab)) {
|
| - if (!ReadFromOffsetExact(fd, &strtab, sizeof(strtab), elf_header.e_shoff +
|
| - symtab.sh_link * sizeof(symtab))) {
|
| - return false;
|
| - }
|
| - if (FindSymbol(pc, fd, out, out_size, symbol_offset,
|
| - &strtab, &symtab)) {
|
| - return true; // Found the symbol in a regular symbol table.
|
| - }
|
| - }
|
| -
|
| - // If the symbol is not found, then consult a dynamic symbol table.
|
| - if (GetSectionHeaderByType(fd, elf_header.e_shnum, elf_header.e_shoff,
|
| - SHT_DYNSYM, &symtab)) {
|
| - if (!ReadFromOffsetExact(fd, &strtab, sizeof(strtab), elf_header.e_shoff +
|
| - symtab.sh_link * sizeof(symtab))) {
|
| - return false;
|
| - }
|
| - if (FindSymbol(pc, fd, out, out_size, symbol_offset,
|
| - &strtab, &symtab)) {
|
| - return true; // Found the symbol in a dynamic symbol table.
|
| - }
|
| - }
|
| -
|
| - return false;
|
| -}
|
| -
|
| -namespace {
|
| -// Thin wrapper around a file descriptor so that the file descriptor
|
| -// gets closed for sure.
|
| -struct FileDescriptor {
|
| - const int fd_;
|
| - explicit FileDescriptor(int fd) : fd_(fd) {}
|
| - ~FileDescriptor() {
|
| - if (fd_ >= 0) {
|
| - NO_INTR(close(fd_));
|
| - }
|
| - }
|
| - int get() { return fd_; }
|
| -
|
| - private:
|
| - explicit FileDescriptor(const FileDescriptor&);
|
| - void operator=(const FileDescriptor&);
|
| -};
|
| -
|
| -// Helper class for reading lines from file.
|
| -//
|
| -// Note: we don't use ProcMapsIterator since the object is big (it has
|
| -// a 5k array member) and uses async-unsafe functions such as sscanf()
|
| -// and snprintf().
|
| -class LineReader {
|
| - public:
|
| - explicit LineReader(int fd, char *buf, int buf_len) : fd_(fd),
|
| - buf_(buf), buf_len_(buf_len), bol_(buf), eol_(buf), eod_(buf) {
|
| - }
|
| -
|
| - // Read '\n'-terminated line from file. On success, modify "bol"
|
| - // and "eol", then return true. Otherwise, return false.
|
| - //
|
| - // Note: if the last line doesn't end with '\n', the line will be
|
| - // dropped. It's an intentional behavior to make the code simple.
|
| - bool ReadLine(const char **bol, const char **eol) {
|
| - if (BufferIsEmpty()) { // First time.
|
| - const ssize_t num_bytes = ReadPersistent(fd_, buf_, buf_len_);
|
| - if (num_bytes <= 0) { // EOF or error.
|
| - return false;
|
| - }
|
| - eod_ = buf_ + num_bytes;
|
| - bol_ = buf_;
|
| - } else {
|
| - bol_ = eol_ + 1; // Advance to the next line in the buffer.
|
| - SAFE_ASSERT(bol_ <= eod_); // "bol_" can point to "eod_".
|
| - if (!HasCompleteLine()) {
|
| - const int incomplete_line_length = eod_ - bol_;
|
| - // Move the trailing incomplete line to the beginning.
|
| - memmove(buf_, bol_, incomplete_line_length);
|
| - // Read text from file and append it.
|
| - char * const append_pos = buf_ + incomplete_line_length;
|
| - const int capacity_left = buf_len_ - incomplete_line_length;
|
| - const ssize_t num_bytes = ReadPersistent(fd_, append_pos,
|
| - capacity_left);
|
| - if (num_bytes <= 0) { // EOF or error.
|
| - return false;
|
| - }
|
| - eod_ = append_pos + num_bytes;
|
| - bol_ = buf_;
|
| - }
|
| - }
|
| - eol_ = FindLineFeed();
|
| - if (eol_ == NULL) { // '\n' not found. Malformed line.
|
| - return false;
|
| - }
|
| - *eol_ = '\0'; // Replace '\n' with '\0'.
|
| -
|
| - *bol = bol_;
|
| - *eol = eol_;
|
| - return true;
|
| - }
|
| -
|
| - // Beginning of line.
|
| - const char *bol() {
|
| - return bol_;
|
| - }
|
| -
|
| - // End of line.
|
| - const char *eol() {
|
| - return eol_;
|
| - }
|
| -
|
| - private:
|
| - explicit LineReader(const LineReader&);
|
| - void operator=(const LineReader&);
|
| -
|
| - char *FindLineFeed() {
|
| - return reinterpret_cast<char *>(memchr(bol_, '\n', eod_ - bol_));
|
| - }
|
| -
|
| - bool BufferIsEmpty() {
|
| - return buf_ == eod_;
|
| - }
|
| -
|
| - bool HasCompleteLine() {
|
| - return !BufferIsEmpty() && FindLineFeed() != NULL;
|
| - }
|
| -
|
| - const int fd_;
|
| - char * const buf_;
|
| - const int buf_len_;
|
| - char *bol_;
|
| - char *eol_;
|
| - const char *eod_; // End of data in "buf_".
|
| -};
|
| -} // namespace
|
| -
|
| -// Place the hex number read from "start" into "*hex". The pointer to
|
| -// the first non-hex character or "end" is returned.
|
| -static char *GetHex(const char *start, const char *end, uint64_t *hex) {
|
| - *hex = 0;
|
| - const char *p;
|
| - for (p = start; p < end; ++p) {
|
| - int ch = *p;
|
| - if ((ch >= '0' && ch <= '9') ||
|
| - (ch >= 'A' && ch <= 'F') || (ch >= 'a' && ch <= 'f')) {
|
| - *hex = (*hex << 4) | (ch < 'A' ? ch - '0' : (ch & 0xF) + 9);
|
| - } else { // Encountered the first non-hex character.
|
| - break;
|
| - }
|
| - }
|
| - SAFE_ASSERT(p <= end);
|
| - return const_cast<char *>(p);
|
| -}
|
| -
|
| -// 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).
|
| -static ATTRIBUTE_NOINLINE int
|
| -OpenObjectFileContainingPcAndGetStartAddress(uint64_t pc,
|
| - uint64_t &start_address,
|
| - uint64_t &base_address,
|
| - char *out_file_name,
|
| - int out_file_name_size) {
|
| - int object_fd;
|
| -
|
| - // Open /proc/self/maps.
|
| - int maps_fd;
|
| - NO_INTR(maps_fd = open("/proc/self/maps", O_RDONLY));
|
| - FileDescriptor wrapped_maps_fd(maps_fd);
|
| - if (wrapped_maps_fd.get() < 0) {
|
| - return -1;
|
| - }
|
| -
|
| - // Iterate over maps and look for the map containing the pc. Then
|
| - // look into the symbol tables inside.
|
| - char buf[1024]; // Big enough for line of sane /proc/self/maps
|
| - int num_maps = 0;
|
| - LineReader reader(wrapped_maps_fd.get(), buf, sizeof(buf));
|
| - while (true) {
|
| - num_maps++;
|
| - const char *cursor;
|
| - const char *eol;
|
| - if (!reader.ReadLine(&cursor, &eol)) { // EOF or malformed line.
|
| - return -1;
|
| - }
|
| -
|
| - // Start parsing line in /proc/self/maps. Here is an example:
|
| - //
|
| - // 08048000-0804c000 r-xp 00000000 08:01 2142121 /bin/cat
|
| - //
|
| - // We want start address (08048000), end address (0804c000), flags
|
| - // (r-xp) and file name (/bin/cat).
|
| -
|
| - // Read start address.
|
| - cursor = GetHex(cursor, eol, &start_address);
|
| - if (cursor == eol || *cursor != '-') {
|
| - return -1; // Malformed line.
|
| - }
|
| - ++cursor; // Skip '-'.
|
| -
|
| - // Read end address.
|
| - uint64_t end_address;
|
| - cursor = GetHex(cursor, eol, &end_address);
|
| - if (cursor == eol || *cursor != ' ') {
|
| - return -1; // Malformed line.
|
| - }
|
| - ++cursor; // Skip ' '.
|
| -
|
| - // Check start and end addresses.
|
| - if (!(start_address <= pc && pc < end_address)) {
|
| - continue; // We skip this map. PC isn't in this map.
|
| - }
|
| -
|
| - // Read flags. Skip flags until we encounter a space or eol.
|
| - const char * const flags_start = cursor;
|
| - while (cursor < eol && *cursor != ' ') {
|
| - ++cursor;
|
| - }
|
| - // We expect at least four letters for flags (ex. "r-xp").
|
| - if (cursor == eol || cursor < flags_start + 4) {
|
| - return -1; // Malformed line.
|
| - }
|
| -
|
| - // Check flags. We are only interested in "r-x" maps.
|
| - if (memcmp(flags_start, "r-x", 3) != 0) { // Not a "r-x" map.
|
| - continue; // We skip this map.
|
| - }
|
| - ++cursor; // Skip ' '.
|
| -
|
| - // Read file offset.
|
| - uint64_t file_offset;
|
| - cursor = GetHex(cursor, eol, &file_offset);
|
| - if (cursor == eol || *cursor != ' ') {
|
| - return -1; // Malformed line.
|
| - }
|
| - ++cursor; // Skip ' '.
|
| -
|
| - // Don't subtract 'start_address' from the first entry:
|
| - // * If a binary is compiled w/o -pie, then the first entry in
|
| - // process maps is likely the binary itself (all dynamic libs
|
| - // are mapped higher in address space). For such a binary,
|
| - // instruction offset in binary coincides with the actual
|
| - // instruction address in virtual memory (as code section
|
| - // is mapped to a fixed memory range).
|
| - // * If a binary is compiled with -pie, all the modules are
|
| - // mapped high at address space (in particular, higher than
|
| - // shadow memory of the tool), so the module can't be the
|
| - // first entry.
|
| - base_address = ((num_maps == 1) ? 0U : start_address) - file_offset;
|
| -
|
| - // Skip to file name. "cursor" now points to dev. We need to
|
| - // skip at least two spaces for dev and inode.
|
| - int num_spaces = 0;
|
| - while (cursor < eol) {
|
| - if (*cursor == ' ') {
|
| - ++num_spaces;
|
| - } else if (num_spaces >= 2) {
|
| - // The first non-space character after skipping two spaces
|
| - // is the beginning of the file name.
|
| - break;
|
| - }
|
| - ++cursor;
|
| - }
|
| - if (cursor == eol) {
|
| - return -1; // Malformed line.
|
| - }
|
| -
|
| - // Finally, "cursor" now points to file name of our interest.
|
| - NO_INTR(object_fd = open(cursor, O_RDONLY));
|
| - if (object_fd < 0) {
|
| - // Failed to open object file. Copy the object file name to
|
| - // |out_file_name|.
|
| - strncpy(out_file_name, cursor, out_file_name_size);
|
| - // Making sure |out_file_name| is always null-terminated.
|
| - out_file_name[out_file_name_size - 1] = '\0';
|
| - return -1;
|
| - }
|
| - return object_fd;
|
| - }
|
| -}
|
| -
|
| -// POSIX doesn't define any async-signal safe function for converting
|
| -// an integer to ASCII. We'll have to define our own version.
|
| -// itoa_r() converts a (signed) integer to ASCII. It returns "buf", if the
|
| -// conversion was successful or NULL otherwise. It never writes more than "sz"
|
| -// bytes. Output will be truncated as needed, and a NUL character is always
|
| -// appended.
|
| -// NOTE: code from sandbox/linux/seccomp-bpf/demo.cc.
|
| -char *itoa_r(intptr_t i, char *buf, size_t sz, int base, size_t padding) {
|
| - // Make sure we can write at least one NUL byte.
|
| - size_t n = 1;
|
| - if (n > sz)
|
| - return NULL;
|
| -
|
| - if (base < 2 || base > 16) {
|
| - buf[0] = '\000';
|
| - return NULL;
|
| - }
|
| -
|
| - char *start = buf;
|
| -
|
| - uintptr_t j = i;
|
| -
|
| - // Handle negative numbers (only for base 10).
|
| - if (i < 0 && base == 10) {
|
| - // This does "j = -i" while avoiding integer overflow.
|
| - j = static_cast<uintptr_t>(-(i + 1)) + 1;
|
| -
|
| - // Make sure we can write the '-' character.
|
| - if (++n > sz) {
|
| - buf[0] = '\000';
|
| - return NULL;
|
| - }
|
| - *start++ = '-';
|
| - }
|
| -
|
| - // Loop until we have converted the entire number. Output at least one
|
| - // character (i.e. '0').
|
| - char *ptr = start;
|
| - do {
|
| - // Make sure there is still enough space left in our output buffer.
|
| - if (++n > sz) {
|
| - buf[0] = '\000';
|
| - return NULL;
|
| - }
|
| -
|
| - // Output the next digit.
|
| - *ptr++ = "0123456789abcdef"[j % base];
|
| - j /= base;
|
| -
|
| - if (padding > 0)
|
| - padding--;
|
| - } while (j > 0 || padding > 0);
|
| -
|
| - // Terminate the output with a NUL character.
|
| - *ptr = '\000';
|
| -
|
| - // Conversion to ASCII actually resulted in the digits being in reverse
|
| - // order. We can't easily generate them in forward order, as we can't tell
|
| - // the number of characters needed until we are done converting.
|
| - // So, now, we reverse the string (except for the possible "-" sign).
|
| - while (--ptr > start) {
|
| - char ch = *ptr;
|
| - *ptr = *start;
|
| - *start++ = ch;
|
| - }
|
| - return buf;
|
| -}
|
| -
|
| -// Safely appends string |source| to string |dest|. Never writes past the
|
| -// buffer size |dest_size| and guarantees that |dest| is null-terminated.
|
| -void SafeAppendString(const char* source, char* dest, int dest_size) {
|
| - int dest_string_length = strlen(dest);
|
| - SAFE_ASSERT(dest_string_length < dest_size);
|
| - dest += dest_string_length;
|
| - dest_size -= dest_string_length;
|
| - strncpy(dest, source, dest_size);
|
| - // Making sure |dest| is always null-terminated.
|
| - dest[dest_size - 1] = '\0';
|
| -}
|
| -
|
| -// Converts a 64-bit value into a hex string, and safely appends it to |dest|.
|
| -// Never writes past the buffer size |dest_size| and guarantees that |dest| is
|
| -// null-terminated.
|
| -void SafeAppendHexNumber(uint64_t value, char* dest, int dest_size) {
|
| - // 64-bit numbers in hex can have up to 16 digits.
|
| - char buf[17] = {'\0'};
|
| - SafeAppendString(itoa_r(value, buf, sizeof(buf), 16, 0), dest, dest_size);
|
| -}
|
| -
|
| -// The implementation of our symbolization routine. If it
|
| -// successfully finds the symbol containing "pc" and obtains the
|
| -// symbol name, returns true and write the symbol name to "out".
|
| -// Otherwise, returns false. If Callback function is installed via
|
| -// InstallSymbolizeCallback(), the function is also called in this function,
|
| -// and "out" is used as its output.
|
| -// To keep stack consumption low, we would like this function to not
|
| -// get inlined.
|
| -static ATTRIBUTE_NOINLINE bool SymbolizeAndDemangle(void *pc, char *out,
|
| - int out_size) {
|
| - uint64_t pc0 = reinterpret_cast<uintptr_t>(pc);
|
| - uint64_t start_address = 0;
|
| - uint64_t base_address = 0;
|
| - int object_fd = -1;
|
| -
|
| - if (out_size < 1) {
|
| - return false;
|
| - }
|
| - out[0] = '\0';
|
| - SafeAppendString("(", out, out_size);
|
| -
|
| - if (g_symbolize_open_object_file_callback) {
|
| - object_fd = g_symbolize_open_object_file_callback(pc0, start_address,
|
| - base_address, out + 1,
|
| - out_size - 1);
|
| - } else {
|
| - object_fd = OpenObjectFileContainingPcAndGetStartAddress(pc0, start_address,
|
| - base_address,
|
| - out + 1,
|
| - out_size - 1);
|
| - }
|
| -
|
| - // Check whether a file name was returned.
|
| - if (object_fd < 0) {
|
| - if (out[1]) {
|
| - // The object file containing PC was determined successfully however the
|
| - // object file was not opened successfully. This is still considered
|
| - // success because the object file name and offset are known and tools
|
| - // like asan_symbolize.py can be used for the symbolization.
|
| - out[out_size - 1] = '\0'; // Making sure |out| is always null-terminated.
|
| - SafeAppendString("+0x", out, out_size);
|
| - SafeAppendHexNumber(pc0 - base_address, out, out_size);
|
| - SafeAppendString(")", out, out_size);
|
| - return true;
|
| - }
|
| - // Failed to determine the object file containing PC. Bail out.
|
| - return false;
|
| - }
|
| - FileDescriptor wrapped_object_fd(object_fd);
|
| - int elf_type = FileGetElfType(wrapped_object_fd.get());
|
| - if (elf_type == -1) {
|
| - return false;
|
| - }
|
| - if (g_symbolize_callback) {
|
| - // Run the call back if it's installed.
|
| - // Note: relocation (and much of the rest of this code) will be
|
| - // wrong for prelinked shared libraries and PIE executables.
|
| - uint64 relocation = (elf_type == ET_DYN) ? start_address : 0;
|
| - int num_bytes_written = g_symbolize_callback(wrapped_object_fd.get(),
|
| - pc, out, out_size,
|
| - relocation);
|
| - if (num_bytes_written > 0) {
|
| - out += num_bytes_written;
|
| - out_size -= num_bytes_written;
|
| - }
|
| - }
|
| - if (!GetSymbolFromObjectFile(wrapped_object_fd.get(), pc0,
|
| - out, out_size, start_address)) {
|
| - return false;
|
| - }
|
| -
|
| - // Symbolization succeeded. Now we try to demangle the symbol.
|
| - DemangleInplace(out, out_size);
|
| - return true;
|
| -}
|
| -
|
| -_END_GOOGLE_NAMESPACE_
|
| -
|
| -#elif defined(OS_MACOSX) && defined(HAVE_DLADDR)
|
| -
|
| -#include <dlfcn.h>
|
| -#include <string.h>
|
| -
|
| -_START_GOOGLE_NAMESPACE_
|
| -
|
| -static ATTRIBUTE_NOINLINE bool SymbolizeAndDemangle(void *pc, char *out,
|
| - int out_size) {
|
| - Dl_info info;
|
| - if (dladdr(pc, &info)) {
|
| - if ((int)strlen(info.dli_sname) < out_size) {
|
| - strcpy(out, info.dli_sname);
|
| - // Symbolization succeeded. Now we try to demangle the symbol.
|
| - DemangleInplace(out, out_size);
|
| - return true;
|
| - }
|
| - }
|
| - return false;
|
| -}
|
| -
|
| -_END_GOOGLE_NAMESPACE_
|
| -
|
| -#else
|
| -# error BUG: HAVE_SYMBOLIZE was wrongly set
|
| -#endif
|
| -
|
| -_START_GOOGLE_NAMESPACE_
|
| -
|
| -bool Symbolize(void *pc, char *out, int out_size) {
|
| - SAFE_ASSERT(out_size >= 0);
|
| - return SymbolizeAndDemangle(pc, out, out_size);
|
| -}
|
| -
|
| -_END_GOOGLE_NAMESPACE_
|
| -
|
| -#else /* HAVE_SYMBOLIZE */
|
| -
|
| -#include <assert.h>
|
| -
|
| -#include "config.h"
|
| -
|
| -_START_GOOGLE_NAMESPACE_
|
| -
|
| -// TODO: Support other environments.
|
| -bool Symbolize(void *pc, char *out, int out_size) {
|
| - assert(0);
|
| - return false;
|
| -}
|
| -
|
| -_END_GOOGLE_NAMESPACE_
|
| -
|
| -#endif
|
|
|