diff options
| -rw-r--r-- | .udbinit | 1 | ||||
| -rw-r--r-- | buildscripts/gdb/udb.py | 260 |
2 files changed, 261 insertions, 0 deletions
diff --git a/.udbinit b/.udbinit new file mode 100644 index 00000000000..72c8795e3ec --- /dev/null +++ b/.udbinit @@ -0,0 +1 @@ +source buildscripts/gdb/udb.py diff --git a/buildscripts/gdb/udb.py b/buildscripts/gdb/udb.py new file mode 100644 index 00000000000..98fff5b284e --- /dev/null +++ b/buildscripts/gdb/udb.py @@ -0,0 +1,260 @@ +"""Utility functions for udb.""" + +# pylint: disable=unused-argument,missing-docstring,no-self-use +import os +import re +from typing import Optional +import gdb + +# Pattern to match output of 'info files' +PATTERN_ELF_SECTIONS = re.compile( + r'(?P<begin>[0x0-9a-fA-F]+)\s-\s(?P<end>[0x0-9a-fA-F]+)\s\bis\b\s(?P<section>\.[a-z]+$)') + + +def parse_sections(): + """Find addresses for .text, .data, and .bss sections.""" + file_info = gdb.execute('info files', to_string=True) + section_map = {} + for line in file_info.splitlines(): + line = line.strip() + match = PATTERN_ELF_SECTIONS.match(line) + if match is None: + continue + + section = match.group('section') + if section not in ('.text', '.data', '.bss'): + continue + begin = match.group('begin') + section_map[section] = begin + + return section_map + + +def load_sym_file_at_addrs(dbg_file, smap): + """Invoke add-symbol-file with addresses.""" + cmd = 'add-symbol-file {} {} -s .data {} -s .bss {}'.format(dbg_file, smap['.text'], + smap['.data'], smap['.bss']) + gdb.execute(cmd, to_string=True) + + +class LoadDebugFile(gdb.Command): + """Loads the debug symbol file with the correct address for .text, .data and .bss sections.""" + + def __init__(self): + """GDB Command API init.""" + super(LoadDebugFile, self).__init__('load-debug-symbols', gdb.COMPLETE_EXPRESSION) + + def invoke(self, args, from_tty): + """GDB Command API invoke.""" + arglist = args.split() + if len(arglist) != 1: + print('Usage: load-debug-symbols <file_path>') + return + + dbg_file = arglist[0] + if not os.path.exists(dbg_file): + print('{} is not a valid file path'.format(dbg_file)) + return + + try: + section_map = parse_sections() + load_sym_file_at_addrs(dbg_file, section_map) + except Exception as err: # pylint: disable=broad-except + print(err) + + +LoadDebugFile() + +PATTERN_ELF_SOLIB_SECTIONS = re.compile( + r'(?P<begin>[0x0-9a-fA-F]+)\s-\s(?P<end>[0x0-9a-fA-F]+)\s\bis\b\s(?P<section>\.[a-z]+)\s\bin\b\s(?P<file>.*$)' +) + + +def parse_solib_sections(): + """Find addresses for .text, .data, and .bss sections.""" + file_info = gdb.execute('info files', to_string=True) + section_map = {} + for line in file_info.splitlines(): + line = line.strip() + match = PATTERN_ELF_SOLIB_SECTIONS.match(line) + if match is None: + continue + + section = match.group('section') + if section not in ('.text', '.data', '.bss'): + continue + begin = match.group('begin') + # TODO duplicate fnames? + fname = os.path.basename(match.group('file')) + + if fname.startswith("system-supplied DSO") or match.group('file').startswith( + "/lib") or match.group('file').startswith("/usr/lib"): + continue + fname = f"{fname}.debug" + section_map.setdefault(fname, {}) + section_map[fname][section] = begin + + return section_map + + +def is_probably_dwarf_file(fname): + """Check if it's a file, and ends in .debug.""" + return os.path.isfile(fname) and fname.endswith(".debug") + + +def find_dwarf_files(path): + """Given a directory, collect a list of files in it that pass the is_probably_dwarf_file test.""" + out = [] + for fname in os.listdir(path): + full_path = os.path.join(path, fname) + if is_probably_dwarf_file(full_path): + out.append(full_path) + return out + + +SOLIB_SEARCH_PATH_PREFIX = "The search path for loading non-absolute shared library symbol files is " + + +def extend_solib_search_path(new_path: str): + """Extend solib-search-path.""" + solib_search_path = gdb.execute("show solib-search-path", to_string=True) + # remove the prefix and suffix (which is a period and space) from the + # search path + solib_search_path = solib_search_path[len(SOLIB_SEARCH_PATH_PREFIX):-2] + solib_search_path = f"{new_path}:{solib_search_path}" + if solib_search_path.endswith(":"): + solib_search_path = solib_search_path[:-1] + + gdb.execute(f"set solib-search-path {solib_search_path}", to_string=True) + + +DEBUG_FILE_DIRECTORY_PREFIX = 'The directory where separate debug symbols are searched for is "' + + +def extend_debug_file_directory(new_path: str): + """Extend debug-file-directory.""" + debug_file_directory = gdb.execute("show debug-file-directory", to_string=True) + # remove the prefix and suffix (which is a period and space) from the + # search path + debug_file_directory = debug_file_directory[len(DEBUG_FILE_DIRECTORY_PREFIX):-3] + debug_file_directory = f"{new_path}:{debug_file_directory}" + if debug_file_directory.endswith(":"): + debug_file_directory = debug_file_directory[:-1] + + gdb.execute(f"set debug-file-directory {debug_file_directory}", to_string=True) + + +class LoadDistTest(gdb.Command): + """Load all symbol files in a dist-test directory. + + Command assumes provided directory has a bin and lib subdir, and will + add-symbol-file all .debug files in those directories. + """ + + def __init__(self): + """GDB Command API init.""" + super(LoadDistTest, self).__init__('load-dist-test', gdb.COMPLETE_EXPRESSION) + + try: + # test if we're running udb + gdb.execute("help uinfo", to_string=True) + self._is_udb = True + except gdb.error: + self._is_udb = False + + @staticmethod + def binary_name(): + """Fetch the name of the binary gdb is attached to.""" + main_binary_name = gdb.objfiles()[0].filename + main_binary_name = os.path.splitext(os.path.basename(main_binary_name))[0] + if main_binary_name.endswith('mongod'): + return "mongod" + if main_binary_name.endswith('mongo'): + return "mongo" + if main_binary_name.endswith('mongos'): + return "mongos" + + return None + + # pylint: disable=too-many-branches,too-many-locals + def invoke(self, args, from_tty): + """GDB Command API invoke.""" + arglist = args.split() + if not arglist: + arglist = [os.path.abspath("./dist-test")] + print(f"No path provided, assuming '{arglist[0]}'") + + if len(arglist) != 1: + print('Usage: load-dist-test <path/to/dist-test>') + return + + dist_test = arglist[0] + if not os.path.isdir(dist_test): + print(f"'{dist_test}' does not exist, or is not a directory") + return + + if self._is_udb: + # if this is an instance of udb, save a bookmark for the current + # location, and jump to the recording's end + # to make sure the shared libraries have been dlopen'd. This + # ensures that when we try to parse the solib sections, we know + # we have the .text, .bss, .data section addresses available + gdb.execute("ubookmark ____dist_test", to_string=True) + gdb.execute("ugo end", to_string=True) + + dwarf_files = [] + + bin_dir = os.path.join(dist_test, "bin") + if bin_dir: + dwarf_files.extend(find_dwarf_files(bin_dir)) + extend_debug_file_directory(bin_dir) + + lib_dir = os.path.join(dist_test, "lib") + if lib_dir: + dwarf_files.extend(find_dwarf_files(lib_dir)) + extend_solib_search_path(lib_dir) + + if not dwarf_files: + return + + yell_at_user_main_bin = False + try: + print("Loading symbols. This will take a while..") + main_bin = LoadDistTest.binary_name() + if main_bin: + # if we know the name of this executable, load its symbol file + main_bin_sections = parse_sections() + dbg_file = os.path.join(dist_test, "bin", f"{main_bin}.debug") + load_sym_file_at_addrs(dbg_file, main_bin_sections) + + else: + # if we print here, the message will get lost in the noise, so + # we delay that until the end of this function + yell_at_user_main_bin = True + + section_map = parse_solib_sections() + for idx, dwarf_file in enumerate(dwarf_files): + base_name = os.path.basename(dwarf_file) + if base_name not in section_map: + continue + + load_sym_file_at_addrs(dwarf_file, section_map[base_name]) + if (idx + 1) % 50 == 0 or len(dwarf_files) == idx + 1: + print(f"{idx+1}/{len(dwarf_files)} symbol files loaded") + + except Exception as err: # pylint: disable=broad-except + print(err) + + if self._is_udb: + # if this is an instance of udb, jump to the bookmark we made + # earlier to be nice to the user + gdb.execute("ugo bookmark ____dist_test", to_string=True) + + if yell_at_user_main_bin: + print( + f"Failed to automagically locate debug symbols for main binary. Try loading them manually, 'load-debug-symbols {dist_test}/bin/[your_binary_symbols.debug]'" + ) + print("^^^^^^ HEY LISTEN ^^^^^^") + + +LoadDistTest() |