| // Copyright 2016 The Chromium OS Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "dso.h" |
| |
| #include <elf.h> |
| #include <fcntl.h> |
| #include <string.h> |
| #include <sys/stat.h> |
| #include <sys/sysmacros.h> |
| #include <unistd.h> |
| |
| #include <algorithm> |
| #include <vector> |
| |
| #include <build_id.h> |
| #include <read_elf.h> |
| |
| #include "base/logging.h" |
| #include "compat/string.h" |
| #include "file_reader.h" |
| |
| namespace quipper { |
| |
| void InitializeLibelf() { |
| // Unnecessary. |
| } |
| |
| bool ReadElfBuildId(const string &filename, string *buildid) { |
| BuildId id; |
| ElfStatus status = GetBuildIdFromElfFile(filename, &id); |
| if (status == ElfStatus::NO_ERROR) { |
| *buildid = id.ToString(); |
| return true; |
| } |
| return false; |
| } |
| |
| bool ReadElfBuildId(int fd, string *buildid) { |
| // TODO: Implement. b/74410255. |
| return false; |
| } |
| |
| // read /sys/module/<module_name>/notes/.note.gnu.build-id |
| bool ReadModuleBuildId(const string &module_name, string *buildid) { |
| string note_filename = |
| "/sys/module/" + module_name + "/notes/.note.gnu.build-id"; |
| |
| FileReader file(note_filename); |
| if (!file.IsOpen()) return false; |
| |
| return ReadBuildIdNote(&file, buildid); |
| } |
| |
| bool ReadBuildIdNote(DataReader *data, string *buildid) { |
| // Non-simpleperf implementation, as a reader is given. |
| Elf64_Nhdr note_header; |
| |
| while (data->ReadData(sizeof(note_header), ¬e_header)) { |
| size_t name_size = Align<4>(note_header.n_namesz); |
| size_t desc_size = Align<4>(note_header.n_descsz); |
| |
| string name; |
| if (!data->ReadString(name_size, &name)) return false; |
| string desc; |
| if (!data->ReadDataString(desc_size, &desc)) return false; |
| if (note_header.n_type == NT_GNU_BUILD_ID && name == ELF_NOTE_GNU) { |
| *buildid = desc; |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| bool IsKernelNonModuleName(string name) { |
| // List from kernel: tools/perf/util/dso.c : __kmod_path__parse() |
| static const std::vector<string> kKernelNonModuleNames{ |
| "[kernel.kallsyms]", |
| "[guest.kernel.kallsyms", |
| "[vdso]", |
| "[vsyscall]", |
| }; |
| |
| for (const auto &n : kKernelNonModuleNames) { |
| if (name.compare(0, n.size(), n) == 0) return true; |
| } |
| return false; |
| } |
| |
| // Do the |DSOInfo| and |struct stat| refer to the same inode? |
| bool SameInode(const DSOInfo &dso, const struct stat *s) { |
| return dso.maj == major(s->st_dev) && dso.min == minor(s->st_dev) && |
| dso.ino == s->st_ino; |
| } |
| |
| } // namespace quipper |