1 files changed, 91 insertions, 0 deletions
diff --git a/liblogfs/groupset.c b/liblogfs/groupset.c
new file mode 100644
index 00000000..91b18c9e
--- /dev/null
+++ b/liblogfs/groupset.c
@@ -0,0 +1,91 @@
+#include "lib9.h"
+#include "logfs.h"
+#include "local.h"
+
+struct GroupSet {
+	int maxentries;
+	int nentries;
+	Group **entry;
+};
+
+char *
+logfsgroupsetnew(GroupSet **gsp)
+{
+	GroupSet *gs = logfsrealloc(nil, sizeof(*gs));
+	if(gs == nil)
+		return Enomem;
+	gs->entry = logfsrealloc(nil, sizeof(Group *));
+	if(gs->entry == nil) {
+		logfsfreemem(gs);
+		return Enomem;
+	}
+	gs->maxentries = 1;		/* most groups have one member */
+	gs->nentries = 0;
+	*gsp = gs;
+	return nil;
+}
+
+void
+logfsgroupsetfree(GroupSet **gsp)
+{
+	GroupSet *gs = *gsp;
+	if(gs) {
+		logfsfreemem(gs->entry);
+		logfsfreemem(gs);
+		*gsp = nil;
+	}
+}
+
+int
+logfsgroupsetadd(GroupSet *gs, Group *g)
+{
+	int x;
+	for(x = 0; x < gs->nentries; x++)
+		if(gs->entry[x] == g)
+			return 1;
+	if(gs->nentries >= gs->maxentries) {
+		Group **ne = logfsrealloc(gs->entry, sizeof(Group *) + (gs->maxentries * 2));
+		if(ne)
+			return 0;
+		gs->entry = ne;
+		gs->maxentries *= 2;
+	}
+	gs->entry[gs->nentries++] = g;
+	return 1;
+}
+
+int
+logfsgroupsetremove(GroupSet *gs, Group *g)
+{
+	int x;
+	for(x = 0; x < gs->nentries; x++)
+		if(gs->entry[x] == g)
+			break;
+	if(x == gs->nentries)
+		return 0;
+	gs->nentries--;
+	memmove(&gs->entry[x], &gs->entry[x + 1], sizeof(Group *) * (gs->nentries - x));
+	return 1;
+}
+
+int
+logfsgroupsetwalk(GroupSet *gs, LOGFSGROUPSETWALKFN *func, void *magic)
+{
+	int x;
+	for(x = 0; x < gs->nentries; x++) {
+		int rv = (*func)(magic, gs->entry[x]);
+		if(rv <= 0)
+			return rv;
+	}
+	return 1;
+}
+
+int
+logfsgroupsetismember(GroupSet *gs, Group *g)
+{
+	int x;
+	for(x = 0; x < gs->nentries; x++)
+		if(gs->entry[x] == g)
+			return 1;
+	return 0;
+}