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//===-- sanitizer_symbolizer.h ----------------------------------*- C++ -*-===//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
// Symbolizer is used by sanitizers to map instruction address to a location in
// source code at run-time. Symbolizer either uses __sanitizer_symbolize_*
// defined in the program, or (if they are missing) tries to find and
// launch "llvm-symbolizer" commandline tool in a separate process and
// communicate with it.
// Generally we should try to avoid calling system library functions during
// symbolization (and use their replacements from sanitizer_libc.h instead).
#include "sanitizer_allocator_internal.h"
#include "sanitizer_internal_defs.h"
#include "sanitizer_libc.h"
namespace __sanitizer {
struct AddressInfo {
uptr address;
char *module;
uptr module_offset;
static const uptr kUnknown = ~(uptr)0;
char *function;
uptr function_offset;
char *file;
int line;
int column;
AddressInfo() {
internal_memset(this, 0, sizeof(AddressInfo));
function_offset = kUnknown;
// Deletes all strings and resets all fields.
void Clear() {
internal_memset(this, 0, sizeof(AddressInfo));
function_offset = kUnknown;
void FillAddressAndModuleInfo(uptr addr, const char *mod_name,
uptr mod_offset) {
address = addr;
module = internal_strdup(mod_name);
module_offset = mod_offset;
struct DataInfo {
uptr address;
char *module;
uptr module_offset;
char *name;
uptr start;
uptr size;
class Symbolizer {
/// Returns platform-specific implementation of Symbolizer. The symbolizer
/// must be initialized (with init or disable) before calling this function.
static Symbolizer *Get();
/// Returns platform-specific implementation of Symbolizer, or null if not
/// initialized.
static Symbolizer *GetOrNull();
/// Returns platform-specific implementation of Symbolizer. Will
/// automatically initialize symbolizer as if by calling Init(0) if needed.
static Symbolizer *GetOrInit();
/// Initialize and return the symbolizer, given an optional path to an
/// external symbolizer. The path argument is only required for legacy
/// reasons as this function will check $PATH for an external symbolizer. Not
/// thread safe.
static Symbolizer *Init(const char* path_to_external = 0);
// Fills at most "max_frames" elements of "frames" with descriptions
// for a given address (in all inlined functions). Returns the number
// of descriptions actually filled.
virtual uptr SymbolizePC(uptr address, AddressInfo *frames, uptr max_frames) {
return 0;
virtual bool SymbolizeData(uptr address, DataInfo *info) {
return false;
virtual bool GetModuleNameAndOffsetForPC(uptr pc, const char **module_name,
uptr *module_address) {
return false;
virtual bool CanReturnFileLineInfo() {
return false;
// Release internal caches (if any).
virtual void Flush() {}
// Attempts to demangle the provided C++ mangled name.
virtual const char *Demangle(const char *name) {
return name;
virtual void PrepareForSandboxing() {}
// Allow user to install hooks that would be called before/after Symbolizer
// does the actual file/line info fetching. Specific sanitizers may need this
// to distinguish system library calls made in user code from calls made
// during in-process symbolization.
typedef void (*StartSymbolizationHook)();
typedef void (*EndSymbolizationHook)();
// May be called at most once.
void AddHooks(StartSymbolizationHook start_hook,
EndSymbolizationHook end_hook);
/// Platform-specific function for creating a Symbolizer object.
static Symbolizer *PlatformInit(const char *path_to_external);
/// Create a symbolizer and store it to symbolizer_ without checking if one
/// already exists. Not thread safe.
static Symbolizer *CreateAndStore(const char *path_to_external);
/// Initialize the symbolizer in a disabled state. Not thread safe.
static Symbolizer *Disable();
static Symbolizer *symbolizer_;
static StaticSpinMutex init_mu_;
static LowLevelAllocator symbolizer_allocator_;
StartSymbolizationHook start_hook_;
EndSymbolizationHook end_hook_;
class SymbolizerScope {
explicit SymbolizerScope(const Symbolizer *sym);
const Symbolizer *sym_;
} // namespace __sanitizer