| //===-- sanitizer_symbolizer_libcdep.cc -----------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file is shared between AddressSanitizer and ThreadSanitizer |
| // run-time libraries. See sanitizer_symbolizer.h for details. |
| //===----------------------------------------------------------------------===// |
| |
| #include "sanitizer_allocator_internal.h" |
| #include "sanitizer_common.h" |
| #include "sanitizer_placement_new.h" |
| #include "sanitizer_procmaps.h" |
| #include "sanitizer_symbolizer.h" |
| |
| namespace __sanitizer { |
| |
| void AddressInfo::Clear() { |
| InternalFree(module); |
| InternalFree(function); |
| InternalFree(file); |
| internal_memset(this, 0, sizeof(AddressInfo)); |
| } |
| |
| LoadedModule::LoadedModule(const char *module_name, uptr base_address) { |
| full_name_ = internal_strdup(module_name); |
| base_address_ = base_address; |
| n_ranges_ = 0; |
| } |
| |
| void LoadedModule::addAddressRange(uptr beg, uptr end) { |
| CHECK_LT(n_ranges_, kMaxNumberOfAddressRanges); |
| ranges_[n_ranges_].beg = beg; |
| ranges_[n_ranges_].end = end; |
| n_ranges_++; |
| } |
| |
| bool LoadedModule::containsAddress(uptr address) const { |
| for (uptr i = 0; i < n_ranges_; i++) { |
| if (ranges_[i].beg <= address && address < ranges_[i].end) |
| return true; |
| } |
| return false; |
| } |
| |
| // Extracts the prefix of "str" that consists of any characters not |
| // present in "delims" string, and copies this prefix to "result", allocating |
| // space for it. |
| // Returns a pointer to "str" after skipping extracted prefix and first |
| // delimiter char. |
| static const char *ExtractToken(const char *str, const char *delims, |
| char **result) { |
| uptr prefix_len = internal_strcspn(str, delims); |
| *result = (char*)InternalAlloc(prefix_len + 1); |
| internal_memcpy(*result, str, prefix_len); |
| (*result)[prefix_len] = '\0'; |
| const char *prefix_end = str + prefix_len; |
| if (*prefix_end != '\0') prefix_end++; |
| return prefix_end; |
| } |
| |
| // Same as ExtractToken, but converts extracted token to integer. |
| static const char *ExtractInt(const char *str, const char *delims, |
| int *result) { |
| char *buff; |
| const char *ret = ExtractToken(str, delims, &buff); |
| if (buff != 0) { |
| *result = (int)internal_atoll(buff); |
| } |
| InternalFree(buff); |
| return ret; |
| } |
| |
| static const char *ExtractUptr(const char *str, const char *delims, |
| uptr *result) { |
| char *buff; |
| const char *ret = ExtractToken(str, delims, &buff); |
| if (buff != 0) { |
| *result = (uptr)internal_atoll(buff); |
| } |
| InternalFree(buff); |
| return ret; |
| } |
| |
| // ExternalSymbolizer encapsulates communication between the tool and |
| // external symbolizer program, running in a different subprocess, |
| // For now we assume the following protocol: |
| // For each request of the form |
| // <module_name> <module_offset> |
| // passed to STDIN, external symbolizer prints to STDOUT response: |
| // <function_name> |
| // <file_name>:<line_number>:<column_number> |
| // <function_name> |
| // <file_name>:<line_number>:<column_number> |
| // ... |
| // <empty line> |
| class ExternalSymbolizer { |
| public: |
| ExternalSymbolizer(const char *path, int input_fd, int output_fd) |
| : path_(path), |
| input_fd_(input_fd), |
| output_fd_(output_fd), |
| times_restarted_(0) { |
| CHECK(path_); |
| CHECK_NE(input_fd_, kInvalidFd); |
| CHECK_NE(output_fd_, kInvalidFd); |
| } |
| |
| char *SendCommand(bool is_data, const char *module_name, uptr module_offset) { |
| CHECK(module_name); |
| internal_snprintf(buffer_, kBufferSize, "%s\"%s\" 0x%zx\n", |
| is_data ? "DATA " : "", module_name, module_offset); |
| if (!writeToSymbolizer(buffer_, internal_strlen(buffer_))) |
| return 0; |
| if (!readFromSymbolizer(buffer_, kBufferSize)) |
| return 0; |
| return buffer_; |
| } |
| |
| bool Restart() { |
| if (times_restarted_ >= kMaxTimesRestarted) return false; |
| times_restarted_++; |
| internal_close(input_fd_); |
| internal_close(output_fd_); |
| return StartSymbolizerSubprocess(path_, &input_fd_, &output_fd_); |
| } |
| |
| void Flush() { |
| } |
| |
| private: |
| bool readFromSymbolizer(char *buffer, uptr max_length) { |
| if (max_length == 0) |
| return true; |
| uptr read_len = 0; |
| while (true) { |
| uptr just_read = internal_read(input_fd_, buffer + read_len, |
| max_length - read_len); |
| // We can't read 0 bytes, as we don't expect external symbolizer to close |
| // its stdout. |
| if (just_read == 0 || just_read == (uptr)-1) { |
| Report("WARNING: Can't read from symbolizer at fd %d\n", input_fd_); |
| return false; |
| } |
| read_len += just_read; |
| // Empty line marks the end of symbolizer output. |
| if (read_len >= 2 && buffer[read_len - 1] == '\n' && |
| buffer[read_len - 2] == '\n') { |
| break; |
| } |
| } |
| return true; |
| } |
| |
| bool writeToSymbolizer(const char *buffer, uptr length) { |
| if (length == 0) |
| return true; |
| uptr write_len = internal_write(output_fd_, buffer, length); |
| if (write_len == 0 || write_len == (uptr)-1) { |
| Report("WARNING: Can't write to symbolizer at fd %d\n", output_fd_); |
| return false; |
| } |
| return true; |
| } |
| |
| const char *path_; |
| int input_fd_; |
| int output_fd_; |
| |
| static const uptr kBufferSize = 16 * 1024; |
| char buffer_[kBufferSize]; |
| |
| static const uptr kMaxTimesRestarted = 5; |
| uptr times_restarted_; |
| }; |
| |
| static LowLevelAllocator symbolizer_allocator; // Linker initialized. |
| |
| #if SANITIZER_SUPPORTS_WEAK_HOOKS |
| extern "C" { |
| SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE |
| bool __sanitizer_symbolize_code(const char *ModuleName, u64 ModuleOffset, |
| char *Buffer, int MaxLength); |
| SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE |
| bool __sanitizer_symbolize_data(const char *ModuleName, u64 ModuleOffset, |
| char *Buffer, int MaxLength); |
| SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE |
| void __sanitizer_symbolize_flush(); |
| SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE |
| int __sanitizer_symbolize_demangle(const char *Name, char *Buffer, |
| int MaxLength); |
| } // extern "C" |
| |
| class InternalSymbolizer { |
| public: |
| typedef bool (*SanitizerSymbolizeFn)(const char*, u64, char*, int); |
| |
| static InternalSymbolizer *get() { |
| if (__sanitizer_symbolize_code != 0 && |
| __sanitizer_symbolize_data != 0) { |
| void *mem = symbolizer_allocator.Allocate(sizeof(InternalSymbolizer)); |
| return new(mem) InternalSymbolizer(); |
| } |
| return 0; |
| } |
| |
| char *SendCommand(bool is_data, const char *module_name, uptr module_offset) { |
| SanitizerSymbolizeFn symbolize_fn = is_data ? __sanitizer_symbolize_data |
| : __sanitizer_symbolize_code; |
| if (symbolize_fn(module_name, module_offset, buffer_, kBufferSize)) |
| return buffer_; |
| return 0; |
| } |
| |
| void Flush() { |
| if (__sanitizer_symbolize_flush) |
| __sanitizer_symbolize_flush(); |
| } |
| |
| const char *Demangle(const char *name) { |
| if (__sanitizer_symbolize_demangle) { |
| for (uptr res_length = 1024; |
| res_length <= InternalSizeClassMap::kMaxSize;) { |
| char *res_buff = static_cast<char*>(InternalAlloc(res_length)); |
| uptr req_length = |
| __sanitizer_symbolize_demangle(name, res_buff, res_length); |
| if (req_length > res_length) { |
| res_length = req_length + 1; |
| InternalFree(res_buff); |
| continue; |
| } |
| return res_buff; |
| } |
| } |
| return name; |
| } |
| |
| private: |
| InternalSymbolizer() { } |
| |
| static const int kBufferSize = 16 * 1024; |
| static const int kMaxDemangledNameSize = 1024; |
| char buffer_[kBufferSize]; |
| }; |
| #else // SANITIZER_SUPPORTS_WEAK_HOOKS |
| |
| class InternalSymbolizer { |
| public: |
| static InternalSymbolizer *get() { return 0; } |
| char *SendCommand(bool is_data, const char *module_name, uptr module_offset) { |
| return 0; |
| } |
| void Flush() { } |
| const char *Demangle(const char *name) { return name; } |
| }; |
| |
| #endif // SANITIZER_SUPPORTS_WEAK_HOOKS |
| |
| class Symbolizer { |
| // This class has no constructor, as global constructors are forbidden in |
| // sanitizer_common. It should be linker initialized instead. |
| public: |
| uptr SymbolizeCode(uptr addr, AddressInfo *frames, uptr max_frames) { |
| if (max_frames == 0) |
| return 0; |
| LoadedModule *module = FindModuleForAddress(addr); |
| if (module == 0) |
| return 0; |
| const char *module_name = module->full_name(); |
| uptr module_offset = addr - module->base_address(); |
| const char *str = SendCommand(false, module_name, module_offset); |
| if (str == 0) { |
| // External symbolizer was not initialized or failed. Fill only data |
| // about module name and offset. |
| AddressInfo *info = &frames[0]; |
| info->Clear(); |
| info->FillAddressAndModuleInfo(addr, module_name, module_offset); |
| return 1; |
| } |
| uptr frame_id = 0; |
| for (frame_id = 0; frame_id < max_frames; frame_id++) { |
| AddressInfo *info = &frames[frame_id]; |
| char *function_name = 0; |
| str = ExtractToken(str, "\n", &function_name); |
| CHECK(function_name); |
| if (function_name[0] == '\0') { |
| // There are no more frames. |
| break; |
| } |
| info->Clear(); |
| info->FillAddressAndModuleInfo(addr, module_name, module_offset); |
| info->function = function_name; |
| // Parse <file>:<line>:<column> buffer. |
| char *file_line_info = 0; |
| str = ExtractToken(str, "\n", &file_line_info); |
| CHECK(file_line_info); |
| const char *line_info = ExtractToken(file_line_info, ":", &info->file); |
| line_info = ExtractInt(line_info, ":", &info->line); |
| line_info = ExtractInt(line_info, "", &info->column); |
| InternalFree(file_line_info); |
| |
| // Functions and filenames can be "??", in which case we write 0 |
| // to address info to mark that names are unknown. |
| if (0 == internal_strcmp(info->function, "??")) { |
| InternalFree(info->function); |
| info->function = 0; |
| } |
| if (0 == internal_strcmp(info->file, "??")) { |
| InternalFree(info->file); |
| info->file = 0; |
| } |
| } |
| if (frame_id == 0) { |
| // Make sure we return at least one frame. |
| AddressInfo *info = &frames[0]; |
| info->Clear(); |
| info->FillAddressAndModuleInfo(addr, module_name, module_offset); |
| frame_id = 1; |
| } |
| return frame_id; |
| } |
| |
| bool SymbolizeData(uptr addr, DataInfo *info) { |
| LoadedModule *module = FindModuleForAddress(addr); |
| if (module == 0) |
| return false; |
| const char *module_name = module->full_name(); |
| uptr module_offset = addr - module->base_address(); |
| internal_memset(info, 0, sizeof(*info)); |
| info->address = addr; |
| info->module = internal_strdup(module_name); |
| info->module_offset = module_offset; |
| const char *str = SendCommand(true, module_name, module_offset); |
| if (str == 0) |
| return true; |
| str = ExtractToken(str, "\n", &info->name); |
| str = ExtractUptr(str, " ", &info->start); |
| str = ExtractUptr(str, "\n", &info->size); |
| info->start += module->base_address(); |
| return true; |
| } |
| |
| bool InitializeExternalSymbolizer(const char *path_to_symbolizer) { |
| int input_fd, output_fd; |
| if (!StartSymbolizerSubprocess(path_to_symbolizer, &input_fd, &output_fd)) |
| return false; |
| void *mem = symbolizer_allocator.Allocate(sizeof(ExternalSymbolizer)); |
| external_symbolizer_ = new(mem) ExternalSymbolizer(path_to_symbolizer, |
| input_fd, output_fd); |
| return true; |
| } |
| |
| bool IsSymbolizerAvailable() { |
| if (internal_symbolizer_ == 0) |
| internal_symbolizer_ = InternalSymbolizer::get(); |
| return internal_symbolizer_ || external_symbolizer_; |
| } |
| |
| void Flush() { |
| if (internal_symbolizer_) |
| internal_symbolizer_->Flush(); |
| if (external_symbolizer_) |
| external_symbolizer_->Flush(); |
| } |
| |
| const char *Demangle(const char *name) { |
| if (IsSymbolizerAvailable() && internal_symbolizer_ != 0) |
| return internal_symbolizer_->Demangle(name); |
| return DemangleCXXABI(name); |
| } |
| |
| private: |
| char *SendCommand(bool is_data, const char *module_name, uptr module_offset) { |
| // First, try to use internal symbolizer. |
| if (!IsSymbolizerAvailable()) { |
| return 0; |
| } |
| if (internal_symbolizer_) { |
| return internal_symbolizer_->SendCommand(is_data, module_name, |
| module_offset); |
| } |
| // Otherwise, fall back to external symbolizer. |
| if (external_symbolizer_ == 0) { |
| ReportExternalSymbolizerError( |
| "WARNING: Trying to symbolize code, but external " |
| "symbolizer is not initialized!\n"); |
| return 0; |
| } |
| for (;;) { |
| char *reply = external_symbolizer_->SendCommand(is_data, module_name, |
| module_offset); |
| if (reply) |
| return reply; |
| // Try to restart symbolizer subprocess. If we don't succeed, forget |
| // about it and don't try to use it later. |
| if (!external_symbolizer_->Restart()) { |
| ReportExternalSymbolizerError( |
| "WARNING: Failed to use and restart external symbolizer!\n"); |
| external_symbolizer_ = 0; |
| return 0; |
| } |
| } |
| } |
| |
| LoadedModule *FindModuleForAddress(uptr address) { |
| bool modules_were_reloaded = false; |
| if (modules_ == 0 || !modules_fresh_) { |
| modules_ = (LoadedModule*)(symbolizer_allocator.Allocate( |
| kMaxNumberOfModuleContexts * sizeof(LoadedModule))); |
| CHECK(modules_); |
| n_modules_ = GetListOfModules(modules_, kMaxNumberOfModuleContexts, |
| /* filter */ 0); |
| // FIXME: Return this check when GetListOfModules is implemented on Mac. |
| // CHECK_GT(n_modules_, 0); |
| CHECK_LT(n_modules_, kMaxNumberOfModuleContexts); |
| modules_fresh_ = true; |
| modules_were_reloaded = true; |
| } |
| for (uptr i = 0; i < n_modules_; i++) { |
| if (modules_[i].containsAddress(address)) { |
| return &modules_[i]; |
| } |
| } |
| // Reload the modules and look up again, if we haven't tried it yet. |
| if (!modules_were_reloaded) { |
| // FIXME: set modules_fresh_ from dlopen()/dlclose() interceptors. |
| // It's too aggressive to reload the list of modules each time we fail |
| // to find a module for a given address. |
| modules_fresh_ = false; |
| return FindModuleForAddress(address); |
| } |
| return 0; |
| } |
| |
| void ReportExternalSymbolizerError(const char *msg) { |
| // Don't use atomics here for now, as SymbolizeCode can't be called |
| // from multiple threads anyway. |
| static bool reported; |
| if (!reported) { |
| Report(msg); |
| reported = true; |
| } |
| } |
| |
| // 16K loaded modules should be enough for everyone. |
| static const uptr kMaxNumberOfModuleContexts = 1 << 14; |
| LoadedModule *modules_; // Array of module descriptions is leaked. |
| uptr n_modules_; |
| // If stale, need to reload the modules before looking up addresses. |
| bool modules_fresh_; |
| |
| ExternalSymbolizer *external_symbolizer_; // Leaked. |
| InternalSymbolizer *internal_symbolizer_; // Leaked. |
| }; |
| |
| static Symbolizer symbolizer; // Linker initialized. |
| |
| uptr SymbolizeCode(uptr address, AddressInfo *frames, uptr max_frames) { |
| return symbolizer.SymbolizeCode(address, frames, max_frames); |
| } |
| |
| bool SymbolizeData(uptr address, DataInfo *info) { |
| return symbolizer.SymbolizeData(address, info); |
| } |
| |
| bool InitializeExternalSymbolizer(const char *path_to_symbolizer) { |
| return symbolizer.InitializeExternalSymbolizer(path_to_symbolizer); |
| } |
| |
| bool IsSymbolizerAvailable() { |
| return symbolizer.IsSymbolizerAvailable(); |
| } |
| |
| void FlushSymbolizer() { |
| symbolizer.Flush(); |
| } |
| |
| const char *Demangle(const char *name) { |
| return symbolizer.Demangle(name); |
| } |
| |
| } // namespace __sanitizer |