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Diffstat (limited to 'absl/debugging/internal')
-rw-r--r-- | absl/debugging/internal/symbolize.h | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/absl/debugging/internal/symbolize.h b/absl/debugging/internal/symbolize.h new file mode 100644 index 000000000000..802ea22240df --- /dev/null +++ b/absl/debugging/internal/symbolize.h @@ -0,0 +1,122 @@ +// Copyright 2018 The Abseil Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// This file contains internal parts of the Abseil symbolizer. +// Do not depend on the anything in this file, it may change at anytime. + +#ifndef ABSL_DEBUGGING_INTERNAL_SYMBOLIZE_H_ +#define ABSL_DEBUGGING_INTERNAL_SYMBOLIZE_H_ + +#include <cstddef> +#include <cstdint> + +#ifdef ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE +#error ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE cannot be directly set +#elif defined(__ELF__) && defined(__GLIBC__) && !defined(__native_client__) && \ + !defined(__asmjs__) +#define ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE 1 + +#include <elf.h> +#include <link.h> // For ElfW() macro. +#include <functional> +#include <string> + +namespace absl { +namespace debugging_internal { + +// Iterates over all sections, invoking callback on each with the section name +// and the section header. +// +// Returns true on success; otherwise returns false in case of errors. +// +// This is not async-signal-safe. +bool ForEachSection( + int fd, const std::function<bool(const std::string& name, const ElfW(Shdr) &)>& + callback); + +// 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); + +} // namespace debugging_internal +} // namespace absl + +#endif // ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE + +namespace absl { +namespace debugging_internal { + +struct SymbolDecoratorArgs { + // The program counter we are getting symbolic name for. + const void *pc; + // 0 for main executable, load address for shared libraries. + ptrdiff_t relocation; + // Read-only file descriptor for ELF image covering "pc", + // or -1 if no such ELF image exists in /proc/self/maps. + int fd; + // Output buffer, size. + // Note: the buffer may not be empty -- default symbolizer may have already + // produced some output, and earlier decorators may have adorned it in + // some way. You are free to replace or augment the contents (within the + // symbol_buf_size limit). + char *const symbol_buf; + size_t symbol_buf_size; + // Temporary scratch space, size. + // Use that space in preference to allocating your own stack buffer to + // conserve stack. + char *const tmp_buf; + size_t tmp_buf_size; + // User-provided argument + void* arg; +}; +using SymbolDecorator = void (*)(const SymbolDecoratorArgs *); + +// Installs a function-pointer as a decorator. Returns a value less than zero +// if the system cannot install the decorator. Otherwise, returns a unique +// identifier corresponding to the decorator. This identifier can be used to +// uninstall the decorator - See RemoveSymbolDecorator() below. +int InstallSymbolDecorator(SymbolDecorator decorator, void* arg); + +// Removes a previously installed function-pointer decorator. Parameter "ticket" +// is the return-value from calling InstallSymbolDecorator(). +bool RemoveSymbolDecorator(int ticket); + +// Remove all installed decorators. Returns true if successful, false if +// symbolization is currently in progress. +bool RemoveAllSymbolDecorators(void); + +// Registers an address range to a file mapping. +// +// Preconditions: +// start <= end +// filename != nullptr +// +// Returns true if the file was successfully registered. +bool RegisterFileMappingHint( + const void* start, const void* end, uint64_t offset, const char* filename); + +// Looks up the file mapping registered by RegisterFileMappingHint for an +// address range. If there is one, the file name is stored in *filename and +// *start and *end are modified to reflect the registered mapping. Returns +// whether any hint was found. +bool GetFileMappingHint(const void** start, + const void** end, + uint64_t * offset, + const char** filename); + +} // namespace debugging_internal +} // namespace absl + +#endif // ABSL_DEBUGGING_INTERNAL_SYMBOLIZE_H_ |