https://github.com/python/cpython/commit/bfc16a71cf18015c47c1b9cae9196e279d8f60d7 commit: bfc16a71cf18015c47c1b9cae9196e279d8f60d7 branch: main author: Serhiy Storchaka <[email protected]> committer: serhiy-storchaka <[email protected]> date: 2026-07-29T17:47:52+03:00 summary:
gh-131565: Implement ctypes.util.dllist() in the _ctypes extension (GH-154255) On NetBSD dl_iterate_phdr() reports only the link-map group of the calling object. Called through ctypes, the caller is libffi's closure trampoline, which belongs to no object, so only the main executable was reported. Calling dl_iterate_phdr() from the _ctypes extension module makes _ctypes the caller and reports all loaded shared libraries. Co-Authored-By: Claude Fable 5 <[email protected]> files: A Misc/NEWS.d/next/Library/2026-07-20-17-15-00.gh-issue-131565.dllist.rst M Lib/ctypes/util.py M Modules/_ctypes/callproc.c M configure M configure.ac M pyconfig.h.in diff --git a/Lib/ctypes/util.py b/Lib/ctypes/util.py index c0a578c86549ec9..141d3fbe9382472 100644 --- a/Lib/ctypes/util.py +++ b/Lib/ctypes/util.py @@ -412,53 +412,12 @@ def find_library(name): _get_soname(_findLib_gcc(name)) or _get_soname(_findLib_ld(name)) -# Listing loaded libraries on other systems will try to use -# functions common to Linux and a few other Unix-like systems. -# See the following for several platforms' documentation of the same API: -# https://man7.org/linux/man-pages/man3/dl_iterate_phdr.3.html -# https://man.freebsd.org/cgi/man.cgi?query=dl_iterate_phdr -# https://man.openbsd.org/dl_iterate_phdr -# https://docs.oracle.com/cd/E88353_01/html/E37843/dl-iterate-phdr-3c.html -if (os.name == "posix" and - sys.platform not in {"darwin", "ios", "tvos", "watchos"}): - import ctypes - if hasattr((_libc := ctypes.CDLL(None)), "dl_iterate_phdr"): - - class _dl_phdr_info(ctypes.Structure): - _fields_ = [ - ("dlpi_addr", ctypes.c_void_p), - ("dlpi_name", ctypes.c_char_p), - ("dlpi_phdr", ctypes.c_void_p), - ("dlpi_phnum", ctypes.c_ushort), - ] - - _dl_phdr_callback = ctypes.CFUNCTYPE( - ctypes.c_int, - ctypes.POINTER(_dl_phdr_info), - ctypes.c_size_t, - ctypes.POINTER(ctypes.py_object), - ) - - @_dl_phdr_callback - def _info_callback(info, _size, data): - libraries = data.contents.value - name = os.fsdecode(info.contents.dlpi_name) - libraries.append(name) - return 0 - - _dl_iterate_phdr = _libc["dl_iterate_phdr"] - _dl_iterate_phdr.argtypes = [ - _dl_phdr_callback, - ctypes.POINTER(ctypes.py_object), - ] - _dl_iterate_phdr.restype = ctypes.c_int - - def dllist(): - """Return a list of loaded shared libraries in the current process.""" - libraries = [] - _dl_iterate_phdr(_info_callback, - ctypes.byref(ctypes.py_object(libraries))) - return libraries +# On platforms which provide dl_iterate_phdr(), dllist() is implemented +# in _ctypes. +try: + from _ctypes import dllist +except ImportError: + pass @dataclass(slots=True, frozen=True) diff --git a/Misc/NEWS.d/next/Library/2026-07-20-17-15-00.gh-issue-131565.dllist.rst b/Misc/NEWS.d/next/Library/2026-07-20-17-15-00.gh-issue-131565.dllist.rst new file mode 100644 index 000000000000000..5fb2dd099bd419f --- /dev/null +++ b/Misc/NEWS.d/next/Library/2026-07-20-17-15-00.gh-issue-131565.dllist.rst @@ -0,0 +1,4 @@ +:func:`ctypes.util.dllist` now works on NetBSD. It is implemented in the +:mod:`!_ctypes` extension module so that ``dl_iterate_phdr()`` reports all +loaded shared libraries: on NetBSD it only reports the link-map group of +the calling object, which excluded them when called through ctypes. diff --git a/Modules/_ctypes/callproc.c b/Modules/_ctypes/callproc.c index ccc57e347b07acf..746034c8004c5c4 100644 --- a/Modules/_ctypes/callproc.c +++ b/Modules/_ctypes/callproc.c @@ -1660,6 +1660,42 @@ static PyObject *py_dl_sym(PyObject *self, PyObject *args) PyErr_Format(PyExc_OSError, "symbol '%s' not found", name); return NULL; } + +// Apple platforms use the dyld API in ctypes.util instead. +#if defined(HAVE_DL_ITERATE_PHDR) && !defined(__APPLE__) +#include <link.h> + +static int +_dllist_callback(struct dl_phdr_info *info, size_t size, void *data) +{ + PyObject *list = (PyObject *)data; + PyObject *name = PyUnicode_DecodeFSDefault(info->dlpi_name); + if (name == NULL) { + return -1; + } + int res = PyList_Append(list, name); + Py_DECREF(name); + return res; +} + +static PyObject * +dllist(PyObject *self, PyObject *Py_UNUSED(ignored)) +{ + // On NetBSD dl_iterate_phdr() only reports the link-map group of the + // caller, so it cannot be called via a libffi trampoline. + PyObject *list = PyList_New(0); + if (list == NULL) { + return NULL; + } + // The return value only echoes the callback result. + dl_iterate_phdr(_dllist_callback, list); + if (PyErr_Occurred()) { + Py_DECREF(list); + return NULL; + } + return list; +} +#endif #endif /* @@ -2036,6 +2072,10 @@ PyMethodDef _ctypes_module_methods[] = { "dlopen(name, flag={RTLD_GLOBAL|RTLD_LOCAL}) open a shared library"}, {"dlclose", py_dl_close, METH_VARARGS, "dlclose a library"}, {"dlsym", py_dl_sym, METH_VARARGS, "find symbol in shared library"}, +#if defined(HAVE_DL_ITERATE_PHDR) && !defined(__APPLE__) + {"dllist", dllist, METH_NOARGS, + "dllist() return a list of loaded shared libraries"}, +#endif #endif #ifdef __APPLE__ {"_dyld_shared_cache_contains_path", py_dyld_shared_cache_contains_path, METH_VARARGS, "check if path is in the shared cache"}, diff --git a/configure b/configure index 8e7accb4bc793da..2c82da923f68d4a 100755 --- a/configure +++ b/configure @@ -20229,6 +20229,15 @@ then : fi +# Used by ctypes.util.dllist(). +ac_fn_c_check_func "$LINENO" "dl_iterate_phdr" "ac_cv_func_dl_iterate_phdr" +if test "x$ac_cv_func_dl_iterate_phdr" = xyes +then : + printf "%s\n" "#define HAVE_DL_ITERATE_PHDR 1" >>confdefs.h + +fi + + # DYNLOADFILE specifies which dynload_*.o file we will use for dynamic # loading of modules. diff --git a/configure.ac b/configure.ac index ce146cfa1cbc4cd..771260c76b7f094 100644 --- a/configure.ac +++ b/configure.ac @@ -5421,6 +5421,9 @@ DLINCLDIR=. # platforms have dlopen(), but don't want to use it. AC_CHECK_FUNCS([dlopen]) +# Used by ctypes.util.dllist(). +AC_CHECK_FUNCS([dl_iterate_phdr]) + # DYNLOADFILE specifies which dynload_*.o file we will use for dynamic # loading of modules. AC_SUBST([DYNLOADFILE]) diff --git a/pyconfig.h.in b/pyconfig.h.in index 2658fe8116781db..691c6c0d9feb6d0 100644 --- a/pyconfig.h.in +++ b/pyconfig.h.in @@ -398,6 +398,9 @@ /* Define to 1 if you have the 'dlopen' function. */ #undef HAVE_DLOPEN +/* Define to 1 if you have the 'dl_iterate_phdr' function. */ +#undef HAVE_DL_ITERATE_PHDR + /* Define to 1 if you have the 'dup' function. */ #undef HAVE_DUP _______________________________________________ Python-checkins mailing list -- [email protected] To unsubscribe send an email to [email protected] https://mail.python.org/mailman3//lists/python-checkins.python.org Member address: [email protected]
