implement PID 0 exceptions in C

psutil/_psbsd.py

@@ -911,14 +911,7 @@ def _not_implemented(self):
         @wrap_exceptions
         def open_files(self):
             """Return files opened by process as a list of namedtuples."""
-            if OPENBSD and self.pid == 0:
-                try:
-                    rawlist = cext.proc_open_files(self.pid)
-                except ProcessLookupError:
-                    return []
-            else:
-                rawlist = cext.proc_open_files(self.pid)
-
+            rawlist = cext.proc_open_files(self.pid)
             return [_common.popenfile(path, fd) for path, fd in rawlist]
 
     else:
@@ -931,15 +924,10 @@ def open_files(self):
         @wrap_exceptions
         def num_fds(self):
             """Return the number of file descriptors opened by this process."""
-            if OPENBSD and self.pid == 0:
-                try:
-                    return cext.proc_num_fds(self.pid)
-                except ProcessLookupError:
-                    return 0
-            elif NETBSD:
+            ret = cext.proc_num_fds(self.pid)
+            if NETBSD:
                 self._assert_alive()
-
-            return cext.proc_num_fds(self.pid)
+            return ret
 
     else:
         num_fds = _not_implemented

psutil/arch/bsd/proc.c

@@ -442,8 +442,16 @@ psutil_proc_open_files(PyObject *self, PyObject *args) {
 
     errno = 0;
     freep = kinfo_getfile(pid, &cnt);
+
     if (freep == NULL) {
-#if !defined(PSUTIL_OPENBSD)
+#if defined(PSUTIL_OPENBSD)
+        if ((pid == 0) && (errno == ESRCH)) {
+            psutil_debug(
+                "open_files() returned ESRCH for PID 0; forcing `return []`"
+            );
+            return py_retlist;
+        }
+#else
         psutil_raise_for_pid(pid, "kinfo_getfile()");
 #endif
         goto error;

psutil/arch/openbsd/proc.c

@@ -288,8 +288,17 @@ psutil_proc_num_fds(PyObject *self, PyObject *args) {
         return NULL;
 
     freep = kinfo_getfile(pid, &cnt);
-    if (freep == NULL)
+    if (freep == NULL) {
+#if defined(PSUTIL_OPENBSD)
+        if ((pid == 0) && (errno == ESRCH)) {
+            psutil_debug(
+                "num_fds() returned ESRCH for PID 0; forcing `return 0`"
+            );
+            return Py_BuildValue("i", 0);
+        }
+#endif
         return NULL;
+    }
 
     free(freep);
     return Py_BuildValue("i", cnt);