Am 03.02.2014 13:02, schrieb Andreas Schwab:

Wolfgang Rosenauer writes:

...

So the following question: - what does find-debuginfo.sh do which changes the breakpad ID

How is the breakpad ID computed?

hmm, for details I would need to point you to the google-breakpad project and source code but a quick and overall explanation I got is: "the debug id is either the build ID from the ELF headers, or a hash of the first page of .text" Just found the relevant code: // Attempt to locate a .note.gnu.build-id section in an ELF binary // and copy as many bytes of it as will fit into |identifier|. static bool FindElfBuildIDNote(const void *elf_mapped_base, uint8_t identifier[kMDGUIDSize]) { void* note_section; int note_size, elfclass; if ((!FindElfSegment(elf_mapped_base, PT_NOTE, (const void**)¬e_section, ¬e_size, &elfclass) || note_size == 0) && (!FindElfSection(elf_mapped_base, ".note.gnu.build-id", SHT_NOTE, (const void**)¬e_section, ¬e_size, &elfclass) || note_size == 0)) { return false; } if (elfclass == ELFCLASS32) { return ElfClassBuildIDNoteIdentifier<ElfClass32>(note_section, note_size, identifier); } else if (elfclass == ELFCLASS64) { return ElfClassBuildIDNoteIdentifier<ElfClass64>(note_section, note_size, identifier); } return false; } // Attempt to locate the .text section of an ELF binary and generate // a simple hash by XORing the first page worth of bytes into |identifier|. static bool HashElfTextSection(const void *elf_mapped_base, uint8_t identifier[kMDGUIDSize]) { void* text_section; int text_size; if (!FindElfSection(elf_mapped_base, ".text", SHT_PROGBITS, (const void**)&text_section, &text_size, NULL) || text_size == 0) { return false; } my_memset(identifier, 0, kMDGUIDSize); const uint8_t* ptr = reinterpret_cast(text_section); const uint8_t* ptr_end = ptr + std::min(text_size, 4096); while (ptr < ptr_end) { for (unsigned i = 0; i < kMDGUIDSize; i++) identifier[i] ^= ptr[i]; ptr += kMDGUIDSize; } return true; } // static bool FileID::ElfFileIdentifierFromMappedFile(const void* base, uint8_t identifier[kMDGUIDSize]) { // Look for a build id note first. if (FindElfBuildIDNote(base, identifier)) return true; // Fall back on hashing the first page of the text section. return HashElfTextSection(base, identifier); } -- To unsubscribe, e-mail: opensuse-packaging+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-packaging+owner@opensuse.org