Pythonで広がるXcodeデバッグの世界(pixiv App Night 2025/11/06) / pixiv App Night Xcode debugger with Python

XcodeのデフォルトデバッガであるLLDBは、Pythonを使って拡張することができます。 手軽で便利なものから、外部との連携を行うものまで、いくつかの応用例を紹介します。

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1. 2025/11/06 pixiv App Night PythonͰ޿͕ΔXcodeσόοάͷੈք glass fi ber
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3. • iPad༻͓ֆඳ͖πʔϧ • ΄ͱΜͲͷػೳ͸ແྉͰ࢖༻Մೳ
4. ֓ཁ • XcodeσόοΨ͔ΒݺͿίϚϯυΛPythonͰ࡞Δ • Python͔ΒΞϓϦͷม਺ʹΞΫηε͢Δํ๏ • ίϚϯυͷొ࿥ํ๏ • Ԡ༻ྫ • ωοτϫʔΫܦ༝ͰϓϨϏϡʔΛϦΞϧλΠϜදࣔ
5. • UI͸SwiftɺίΞͷը૾ॲཧ͸C++Ͱهड़
6. σόοΨͰ͸C++ͷը૾ΛϓϨϏϡʔͰ͖ͳ͍ • UIImage΍CGImage͸XcodeͰϓϨϏϡʔͰ͖Δ • C++Ͱ͍࣋ͬͯΔσʔλ͸ϓϨϏϡʔͰ͖ͳ͍ • ഑ྻͱͯ͠਺஋ͷཏྻ͸ݟΕΔ͕… ໨ۄΞΠίϯ ը૾͕දࣔ͞ΕΔ
7. ͦ͏ͩɺPythonΛ࢖͓͏ • XcodeσόοΨ͔ΒPythonεΫϦϓτΛίϚϯυͱͯ͠ݺ΂Δ • Python͔ΒΞϓϦͷม਺ʹΞΫηεͰ͖Δ →PythonͰʮݟΕΔʯܗࣜʹม׵ͯ͠දࣔ͢Ε͹ →ը૾ΛϓϨϏϡʔ͢ΔίϚϯυ͕࡞ΕΔʂ
8. Pythonͷ๛෋ͳϥΠϒϥϦΛ࢖࣮ͬͯݱ • Xcode͔Βݺͼग़͢PythonεΫϦϓτͰ΋ɺpipͰΠϯετʔϧͰ͖Δ ϥΠϒϥϦΛ࢖༻Մೳ • ը૾ม׵ϥΠϒϥϦ Pillow Λ࢖ͬͯRGBA഑ྻΛpngʹม׵ • ม׵ͨ͠pngΛςϯϙϥϦϑΝΠϧʹग़ྗ →ϓϨϏϡʔΞϓϦͰදࣔ
9. ม਺΁ͷΞΫηε def display_CImage(debugger, command, result, internal_dict): args = command.split() var_name = args[0] target = debugger.GetSelectedTarget() process = target.GetProcess() thread = process.GetSelectedThread() frame = thread.GetSelectedFrame() val = frame.FindVariable(var_name) if not val or not val.IsValid(): result.SetError(f"Could not find valiable '{var_name}'") return width_val = val.GetChildMemberWithName('m_width') height_val = val.GetChildMemberWithName('m_height') data_ptr_val = val.GetChildMemberWithName(‘m_buffer') width = width_val.GetValueAsUnsigned(0) height = height_val.GetValueAsUnsigned(0) data_addr = data_ptr_val.GetValueAsUnsigned(0) data_size = width * height * 4 ίϚϯυҾ਺ (ݟ͍ͨը૾ͷม਺໊) ม਺Λݟ͚ͭΔ ϝϯόม਺Λऔಘ PythonͰѻ͑Δ஋ʹ͢Δ σόοΨͷ৘ใ
10. ը૾Λม׵͢Δ image_data = process.ReadMemory(data_addr, data_size, error) try: img = Image.frombytes('RGBA', (width, height), image_data) with tempfile.NamedTemporaryFile(prefix=TEMP_FILE_PREFIX, suffix=“.png”, delete=False) as temp_f: temp_path = temp_f.name img.save(temp_path, 'PNG') try: subprocess.run(['/usr/bin/qlmanage', '-p', temp_path], check=True, stderr=subprocess.DEVNULL, stdout=subprocess.DEVNULL) except FileNotFoundError: … except Exception as e: … RGBA഑ྻ͔Β ը૾ʹม׵ PNGͱͯ͠อଘ Quick LookΛىಈ ྫ֎ॲཧ(লུ)
11. ίϚϯυͱͯ͠ొ࿥͢Δ • __lldb_init_moduleͱ͍͏ؔ਺Λఆ͓͖ٛͯ͠ɺ~/.lldbinitͰimport͢Δ (image_display.py) def __lldb_init_module(debugger, internal_dict): # -f Ϟδϡʔϧ໊.ؔ਺໊ ͷؔ਺Λ disp ͱ͍͏ίϚϯυ໊Ͱొ࿥ debugger.HandleCommand('command script add -f image_display.display_CImage disp') (.lldbinit) command script import ~/lldb_scripts/image_display.py ίϚϯυ໊ εΫϦϓτϑΝΠϧ໊
12. ίϚϯυ࢖༻ྫ
13. ίϚϯυ࢖༻ྫ
14. Ԡ༻ɾωοτϫʔΫͰૹ৴͢Δ • Python͸ωοτϫʔΫΞΫηε΋ࣗ༝ࣗࡏ • ϩʔΧϧͰhttpαʔόʔΛಈ͔͠ɺૹ৴͢Δ • ϒϥ΢βͰࣗಈߋ৽͠ͳ͕Βදࣔ • ϒϨʔΫϙΠϯτͷઃఆ • ActionΛDebugger Commandʹͯ͠ ࡞੒ͨ͠ίϚϯυΛݺͿ • Automatically continue after evaluating actionsΛ༗ޮʹͯ͠ࢭ·Βͳ͍Α͏ʹ͢Δ
15. Ԡ༻ɾωοτϫʔΫͰૹ৴͢Δ • Python͸ωοτϫʔΫΞΫηε΋ࣗ༝ࣗࡏ • ϩʔΧϧͰwebαʔόʔΛಈ͔͠ɺૹ৴͢Δ • ϒϥ΢βͰࣗಈߋ৽͠ͳ͕Βදࣔ
16. Ԡ༻ɾωοτϫʔΫͰૹ৴͢Δ • Python͸ωοτϫʔΫΞΫηε΋ࣗ༝ࣗࡏ • ϩʔΧϧͰwebαʔόʔΛಈ͔͠ɺૹ৴͢Δ • ϒϥ΢βͰࣗಈߋ৽͠ͳ͕Βදࣔ
17. Ԡ༻ɾωοτϫʔΫͰૹ৴͢Δ • Python͸ωοτϫʔΫΞΫηε΋ࣗ༝ࣗࡏ • ϩʔΧϧͰwebαʔόʔΛಈ͔͠ɺૹ৴͢Δ • ϒϥ΢βͰࣗಈߋ৽͠ͳ͕Βදࣔ
18. ·ͱΊ • PythonͰࣗ෼༻ίϚϯυΛ࡞Δ͜ͱͰɺXcodeͰͷσόοά͕ḿΔ • ͱ͸͍͑ɺҰ͔Β࡞Δͷ͸େม… • Facebook(Meta)͕Chiselͱ͍͏LLDBίϚϯυूΛެ։͍ͯ͠Δ • https://github.com/facebook/chisel • ·ͣ͸͜ΕΛಋೖ͠ɺ଍Γͳ͍΋ͷ͚ͩࣗ෼Ͱ࡞Δ