Method CoreFileAnalyzer

src/pystack/_pystack/elf_common.cpp:58–117

}

CoreFileAnalyzer::CoreFileAnalyzer(
        std::string corefile,
        std::optional<std::string> executable,
        const std::optional<std::string>& lib_search_path)
: d_dwfl(nullptr)
, d_debuginfo_path(nullptr)
, d_callbacks()
, d_filename(std::move(corefile))
, d_executable(std::move(executable))
, d_lib_search_path(std::move(lib_search_path))
, d_fd(0)
, d_elf(nullptr)
{
    if (elf_version(EV_CURRENT) == EV_NONE) {
        throw ElfAnalyzerError("libelf library ELF version too old");
    }

    d_fd = open(d_filename.c_str(), O_RDONLY);
    if (d_fd == -1) {
        throw ElfAnalyzerError(
                "Failed to open ELF file '" + d_filename + "' (" + std::strerror(errno) + ")");
    }

    d_elf = elf_unique_ptr(elf_begin(d_fd, ELF_C_READ_MMAP, nullptr), elf_end);
    if (!d_elf) {
        close(d_fd);
        throw ElfAnalyzerError("Cannot read elf file");
    }

    std::memset(&d_callbacks, 0, sizeof(d_callbacks));
    d_callbacks.find_elf = pystack_find_elf;
    d_callbacks.find_debuginfo = dwfl_standard_find_debuginfo;
    d_callbacks.debuginfo_path = &d_debuginfo_path;

    d_dwfl = dwfl_unique_ptr(dwfl_begin(&d_callbacks), dwfl_end);

    if (!d_dwfl) {
        throw ElfAnalyzerError("Failed to initialize core analyzer");
    }

    const char* the_executable = d_executable.has_value() ? d_executable.value().c_str() : nullptr;

    if (dwfl_core_file_report(d_dwfl.get(), d_elf.get(), the_executable) < 0
        || dwfl_report_end(d_dwfl.get(), nullptr, nullptr) != 0)
    {
        throw ElfAnalyzerError(
                "Failed to analyze DWARF information for the core file. '" + d_filename
                + "' doesn't look like a valid core file.");
    }

    resolveLibraries();

    int result = dwfl_core_file_attach(d_dwfl.get(), d_elf.get());
    if (result < 0) {
        throw ElfAnalyzerError(
                "Could not attach the core map analyzer. '" + d_filename
                + "' doesn't look like a valid core file.");
    }