Issue #17557: Fix os.getgroups() to work with the modified behavior of
getgroups(2) on OS X 10.8. Original patch by Mateusz Lenik.
diff --git a/Misc/ACKS b/Misc/ACKS
index aaa8dd4..54fa661f 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -721,6 +721,7 @@
Luke Kenneth Casson Leighton
Tshepang Lekhonkhobe
Marc-André Lemburg
+Mateusz Lenik
John Lenton
Kostyantyn Leschenko
Christopher Tur Lesniewski-Laas
diff --git a/Misc/NEWS b/Misc/NEWS
index 825f6b3..f0cbca2 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -59,6 +59,9 @@
Library
-------
+- Issue #17557: Fix os.getgroups() to work with the modified behavior of
+ getgroups(2) on OS X 10.8. Original patch by Mateusz Lenik.
+
- Issue #18599: Fix name attribute of _sha1.sha1() object. It now returns
'SHA1' instead of 'SHA'.
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 56903c4..32c85b8 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -6331,6 +6331,34 @@
gid_t* alt_grouplist = grouplist;
int n;
+#ifdef __APPLE__
+ /* Issue #17557: As of OS X 10.8, getgroups(2) no longer raises EINVAL if
+ * there are more groups than can fit in grouplist. Therefore, on OS X
+ * always first call getgroups with length 0 to get the actual number
+ * of groups.
+ */
+ n = getgroups(0, NULL);
+ if (n < 0) {
+ return posix_error();
+ } else if (n <= MAX_GROUPS) {
+ /* groups will fit in existing array */
+ alt_grouplist = grouplist;
+ } else {
+ alt_grouplist = PyMem_Malloc(n * sizeof(gid_t));
+ if (alt_grouplist == NULL) {
+ errno = EINVAL;
+ return posix_error();
+ }
+ }
+
+ n = getgroups(n, alt_grouplist);
+ if (n == -1) {
+ if (alt_grouplist != grouplist) {
+ PyMem_Free(alt_grouplist);
+ }
+ return posix_error();
+ }
+#else
n = getgroups(MAX_GROUPS, grouplist);
if (n < 0) {
if (errno == EINVAL) {
@@ -6357,6 +6385,8 @@
return posix_error();
}
}
+#endif
+
result = PyList_New(n);
if (result != NULL) {
int i;