From 3eeb0a833207ecd96f44ad5882b881f8b196f527 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Motiejus=20Jak=C5=A1tys?= <motiejus@jakstys.lt>
Date: Tue, 19 Apr 2022 10:08:37 +0300
Subject: [PATCH] getgrgid

---
 lib/DB.zig | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/lib/DB.zig b/lib/DB.zig
index 36f09e3..78c9462 100644
--- a/lib/DB.zig
+++ b/lib/DB.zig
@@ -276,6 +276,15 @@ fn getgrnam(self: *const DB, name: []const u8, buf: *[]u8) error{OutOfMemory}!?C
     return try self.getGroup(group, buf);
 }
 
+// get a CGroup entry by it's gid.
+fn getgrgid(self: *const DB, gid: u32, buf: *[]u8) error{OutOfMemory}!?CGroup {
+    const idx = bdz.search_u32(self.bdz_gid, gid);
+    const offset = self.idx_gid2group[idx];
+    const group = PackedGroup.fromBytes(self.groups[offset << 3 ..]).group;
+    if (gid != group.gid()) return null;
+    return try self.getGroup(group, buf);
+}
+
 fn shellSections(
     allocator: Allocator,
     corpus: *const Corpus,
@@ -610,6 +619,11 @@ test "high-level API" {
     try testing.expectEqual(cgroup.name[1], 'l');
     try testing.expectEqual(cgroup.name[2], 'l');
     try testing.expectEqual(cgroup.name[3], 0);
+
+    const all_gid = try db.getgrgid(9999, &buf);
+    try testing.expect(all_gid != null);
+    try testing.expectEqual(all_gid.?.gid, 9999);
+    try testing.expectEqualStrings(mem.sliceTo(all_gid.?.name, 0), "all");
 }
 
 test "getgr_bufsize" {