X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/0be976ec0a449279486eec94c33bd58b8c74201b..a2687b64a2eccb39cff400eafdedcaf0f9a2875a:/uidlist.c

diff --git a/uidlist.c b/uidlist.c
index bee35384..d4cb7a03 100644
--- a/uidlist.c
+++ b/uidlist.c
@@ -25,6 +25,13 @@
 
 #include "rsync.h"
 
+#ifdef GETGROUPS_T
+# ifndef NGROUPS_MAX
+/* It ought to be defined, but just in case. */
+#  define NGROUPS_MAX 32
+# endif
+#endif
+
 extern int preserve_uid;
 extern int preserve_gid;
 extern int numeric_ids;
@@ -90,7 +97,8 @@ static uid_t match_uid(uid_t uid)
 	static uid_t last_in, last_out;
 	struct idlist *list = uidlist;
 
-	if (uid == last_in) return last_out;
+	if (uid == last_in)
+		return last_out;
 
 	last_in = uid;
 
@@ -109,7 +117,7 @@ static uid_t match_uid(uid_t uid)
 static int is_in_group(gid_t gid)
 {
 #ifdef GETGROUPS_T
-	static gid_t last_in = (gid_t) -2, last_out;
+	static gid_t last_in = GID_NONE, last_out;
 	static int ngroups = -2;
 	static GETGROUPS_T *gidset;
 	int n;
@@ -117,35 +125,45 @@ static int is_in_group(gid_t gid)
 	if (gid == last_in)
 		return last_out;
 	if (ngroups < -1) {
-		/* treat failure (-1) as if not member of any group */
+		gid_t mygid = getgid();
 		ngroups = getgroups(0, 0);
-		if (ngroups > 0) {
-			gidset = new_array(GETGROUPS_T, ngroups);
+		/* If that didn't work, perhaps 0 isn't treated specially? */
+		if (ngroups <= 0)
+			ngroups = NGROUPS_MAX;
+		gidset = new_array(GETGROUPS_T, ngroups+1);
+		if (ngroups > 0)
 			ngroups = getgroups(ngroups, gidset);
+		/* The default gid might not be in the list on some systems. */
+		for (n = 0; n < ngroups; n++) {
+			if (gidset[n] == mygid)
+				break;
 		}
+		if (n == ngroups)
+			gidset[ngroups++] = mygid;
 	}
 
 	last_in = gid;
-	last_out = 0;
 	for (n = 0; n < ngroups; n++) {
-		if (gidset[n] == gid) {
-			last_out = 1;
-			break;
-		}
+		if (gidset[n] == gid)
+			return last_out = 1;
 	}
-	return last_out;
+	return last_out = 0;
 
 #else
-	return 0;
+	static gid_t mygid = GID_NONE;
+	if (mygid == GID_NONE)
+		mygid = getgid();
+	return gid == mygid;
 #endif
 }
 
 static gid_t match_gid(gid_t gid)
 {
-	static gid_t last_in, last_out;
+	static gid_t last_in = GID_NONE, last_out = GID_NONE;
 	struct idlist *list = gidlist;
 
-	if (gid == last_in) return last_out;
+	if (gid == last_in)
+		return last_out;
 
 	last_in = gid;