bpo-33441: Make the sigset_t converter available in other modules. (GH-6720)

* Expose the sigset_t converter via private API _Py_Sigset_Converter().
* Use Argument Clinic for parsing sigset_t in signalmodule.c.
* Raise ValueError instead OverflowError for integers out of
  the C long range.

Based on patch by Pablo Galindo Salgado.

1 files changed, 25 insertions, 95 deletions

diff --git a/Modules/signalmodule.c b/Modules/signalmodule.c
index 003bbb60e3..818df7d46e 100644
--- a/Modules/signalmodule.c
+++ b/Modules/signalmodule.c
@@ -59,6 +59,14 @@ module signal
 [clinic start generated code]*/
 /*[clinic end generated code: output=da39a3ee5e6b4b0d input=b0301a3bde5fe9d3]*/
 
+/*[python input]
+
+class sigset_t_converter(CConverter):
+    type = 'sigset_t'
+    converter = '_Py_Sigset_Converter'
+
+[python start generated code]*/
+/*[python end generated code: output=da39a3ee5e6b4b0d input=b5689d14466b6823]*/
 
 /*
    NOTES ON THE INTERACTION BETWEEN SIGNALS AND THREADS
@@ -808,69 +816,6 @@ signal_getitimer_impl(PyObject *module, int which)
 
 #endif
 
-#if defined(PYPTHREAD_SIGMASK) || defined(HAVE_SIGWAIT) || \
-        defined(HAVE_SIGWAITINFO) || defined(HAVE_SIGTIMEDWAIT)
-/* Convert an iterable to a sigset.
-   Return 0 on success, return -1 and raise an exception on error. */
-
-static int
-iterable_to_sigset(PyObject *iterable, sigset_t *mask)
-{
-    int result = -1;
-    PyObject *iterator, *item;
-    long signum;
-
-    sigemptyset(mask);
-
-    iterator = PyObject_GetIter(iterable);
-    if (iterator == NULL)
-        goto error;
-
-    while (1)
-    {
-        item = PyIter_Next(iterator);
-        if (item == NULL) {
-            if (PyErr_Occurred())
-                goto error;
-            else
-                break;
-        }
-
-        signum = PyLong_AsLong(item);
-        Py_DECREF(item);
-        if (signum == -1 && PyErr_Occurred())
-            goto error;
-        if (0 < signum && signum < NSIG) {
-            if (sigaddset(mask, (int)signum)) {
-                if (errno != EINVAL) {
-                    /* Probably impossible */
-                    PyErr_SetFromErrno(PyExc_OSError);
-                    goto error;
-                }
-                /* For backwards compatibility, allow idioms such as
-                 * `range(1, NSIG)` but warn about invalid signal numbers
-                 */
-                const char *msg =
-                    "invalid signal number %ld, please use valid_signals()";
-                if (PyErr_WarnFormat(PyExc_RuntimeWarning, 1, msg, signum)) {
-                    goto error;
-                }
-            }
-        }
-        else {
-            PyErr_Format(PyExc_ValueError,
-                         "signal number %ld out of range", signum);
-            goto error;
-        }
-    }
-    result = 0;
-
-error:
-    Py_XDECREF(iterator);
-    return result;
-}
-#endif
-
 #if defined(PYPTHREAD_SIGMASK) || defined(HAVE_SIGPENDING)
 static PyObject*
 sigset_to_set(sigset_t mask)
@@ -913,23 +858,20 @@ sigset_to_set(sigset_t mask)
 signal.pthread_sigmask
 
     how:  int
-    mask: object
+    mask: sigset_t
     /
 
 Fetch and/or change the signal mask of the calling thread.
 [clinic start generated code]*/
 
 static PyObject *
-signal_pthread_sigmask_impl(PyObject *module, int how, PyObject *mask)
-/*[clinic end generated code: output=ff640fe092bc9181 input=f3b7d7a61b7b8283]*/
+signal_pthread_sigmask_impl(PyObject *module, int how, sigset_t mask)
+/*[clinic end generated code: output=0562c0fb192981a8 input=85bcebda442fa77f]*/
 {
-    sigset_t newmask, previous;
+    sigset_t previous;
     int err;
 
-    if (iterable_to_sigset(mask, &newmask))
-        return NULL;
-
-    err = pthread_sigmask(how, &newmask, &previous);
+    err = pthread_sigmask(how, &mask, &previous);
     if (err != 0) {
         errno = err;
         PyErr_SetFromErrno(PyExc_OSError);
@@ -977,7 +919,7 @@ signal_sigpending_impl(PyObject *module)
 /*[clinic input]
 signal.sigwait
 
-    sigset: object
+    sigset: sigset_t
     /
 
 Wait for a signal.
@@ -988,17 +930,13 @@ and returns the signal number.
 [clinic start generated code]*/
 
 static PyObject *
-signal_sigwait(PyObject *module, PyObject *sigset)
-/*[clinic end generated code: output=557173647424f6e4 input=11af2d82d83c2e94]*/
+signal_sigwait_impl(PyObject *module, sigset_t sigset)
+/*[clinic end generated code: output=f43770699d682f96 input=a6fbd47b1086d119]*/
 {
-    sigset_t set;
     int err, signum;
 
-    if (iterable_to_sigset(sigset, &set))
-        return NULL;
-
     Py_BEGIN_ALLOW_THREADS
-    err = sigwait(&set, &signum);
+    err = sigwait(&sigset, &signum);
     Py_END_ALLOW_THREADS
     if (err) {
         errno = err;
@@ -1113,7 +1051,7 @@ fill_siginfo(siginfo_t *si)
 /*[clinic input]
 signal.sigwaitinfo
 
-    sigset: object
+    sigset: sigset_t
     /
 
 Wait synchronously until one of the signals in *sigset* is delivered.
@@ -1122,20 +1060,16 @@ Returns a struct_siginfo containing information about the signal.
 [clinic start generated code]*/
 
 static PyObject *
-signal_sigwaitinfo(PyObject *module, PyObject *sigset)
-/*[clinic end generated code: output=c40f27b269cd2309 input=f3779a74a991e171]*/
+signal_sigwaitinfo_impl(PyObject *module, sigset_t sigset)
+/*[clinic end generated code: output=1eb2f1fa236fdbca input=3d1a7e1f27fc664c]*/
 {
-    sigset_t set;
     siginfo_t si;
     int err;
     int async_err = 0;
 
-    if (iterable_to_sigset(sigset, &set))
-        return NULL;
-
     do {
         Py_BEGIN_ALLOW_THREADS
-        err = sigwaitinfo(&set, &si);
+        err = sigwaitinfo(&sigset, &si);
         Py_END_ALLOW_THREADS
     } while (err == -1
              && errno == EINTR && !(async_err = PyErr_CheckSignals()));
@@ -1152,7 +1086,7 @@ signal_sigwaitinfo(PyObject *module, PyObject *sigset)
 /*[clinic input]
 signal.sigtimedwait
 
-    sigset:  object
+    sigset: sigset_t
     timeout as timeout_obj: object
     /
 
@@ -1162,12 +1096,11 @@ The timeout is specified in seconds, with floating point numbers allowed.
 [clinic start generated code]*/
 
 static PyObject *
-signal_sigtimedwait_impl(PyObject *module, PyObject *sigset,
+signal_sigtimedwait_impl(PyObject *module, sigset_t sigset,
                          PyObject *timeout_obj)
-/*[clinic end generated code: output=f7eff31e679f4312 input=53fd4ea3e3724eb8]*/
+/*[clinic end generated code: output=59c8971e8ae18a64 input=87fd39237cf0b7ba]*/
 {
     struct timespec ts;
-    sigset_t set;
     siginfo_t si;
     int res;
     _PyTime_t timeout, deadline, monotonic;
@@ -1181,9 +1114,6 @@ signal_sigtimedwait_impl(PyObject *module, PyObject *sigset,
         return NULL;
     }
 
-    if (iterable_to_sigset(sigset, &set))
-        return NULL;
-
     deadline = _PyTime_GetMonotonicClock() + timeout;
 
     do {
@@ -1191,7 +1121,7 @@ signal_sigtimedwait_impl(PyObject *module, PyObject *sigset,
             return NULL;
 
         Py_BEGIN_ALLOW_THREADS
-        res = sigtimedwait(&set, &si, &ts);
+        res = sigtimedwait(&sigset, &si, &ts);
         Py_END_ALLOW_THREADS
 
         if (res != -1)