[libglnx] macros: add GLNX_HASH_TABLE_FOREACH_V

[Colin Walters <walters src gnome org>]

commit 5ab15ac175ca45fce1b63a910f8ae2c488b92cfe
Author: Jonathan Lebon <jlebon redhat com>
Date:   Tue Jun 27 20:07:16 2017 -0700

    macros: add GLNX_HASH_TABLE_FOREACH_V
    
    Looking at converting the ostree codebase, iterating over only the
    values of a hash table (while ignoring the key) is actually a more
    common pattern than I thought. So let's give it its own macro as well so
    users don't have to resort to the _KV variant.

 glnx-macros.h               |   11 ++++++++++-
 tests/test-libglnx-macros.c |    8 ++++++++
 2 files changed, 18 insertions(+), 1 deletions(-)
---
diff --git a/glnx-macros.h b/glnx-macros.h
index cee068d..b5127b7 100644
--- a/glnx-macros.h
+++ b/glnx-macros.h
@@ -146,9 +146,10 @@ G_BEGIN_DECLS
  * All variables are scoped within the loop. You may use the `it` variable as
  * usual, e.g. to remove an element using g_hash_table_iter_remove(&it). There
  * are shorter variants for the more common cases where you do not need access
- * to the iterator or to values:
+ * to the iterator or to keys/values:
  *
  *   GLNX_HASH_TABLE_FOREACH (table, const char*, str) { ... }
+ *   GLNX_HASH_TABLE_FOREACH_V (table, MyData*, data) { ... }
  *   GLNX_HASH_TABLE_FOREACH_KV (table, const char*, str, MyData*, data) { ... }
  *
  */
@@ -163,6 +164,14 @@ G_BEGIN_DECLS
          _GLNX_MAKE_ANONYMOUS(_glnx_ht_iter_guard_), ht, \
          _GLNX_MAKE_ANONYMOUS(_glnx_ht_iter_it_), kt, k, vt, v)
 
+/* Variant of GLNX_HASH_TABLE_FOREACH_KV which omits unpacking keys. */
+#define GLNX_HASH_TABLE_FOREACH_V(ht, vt, v) \
+    _GLNX_HASH_TABLE_FOREACH_IMPL_KV( \
+         _GLNX_MAKE_ANONYMOUS(_glnx_ht_iter_guard_), ht, \
+         _GLNX_MAKE_ANONYMOUS(_glnx_ht_iter_it_), \
+         gpointer, _GLNX_MAKE_ANONYMOUS(_glnx_ht_iter_v_), \
+         vt, v)
+
 /* Variant of GLNX_HASH_TABLE_FOREACH_KV which omits unpacking vals. */
 #define GLNX_HASH_TABLE_FOREACH(ht, kt, k) \
     _GLNX_HASH_TABLE_FOREACH_IMPL_KV( \
diff --git a/tests/test-libglnx-macros.c b/tests/test-libglnx-macros.c
index 2a115fc..ffde8fa 100644
--- a/tests/test-libglnx-macros.c
+++ b/tests/test-libglnx-macros.c
@@ -90,6 +90,14 @@ test_hash_table_foreach (void)
       i++;
     }
   g_assert_cmpuint (i, ==, 2);
+
+  i = 0;
+  GLNX_HASH_TABLE_FOREACH_V (table, const char*, val)
+    {
+      g_assert_cmpstr (val, ==, vals[i]);
+      i++;
+    }
+  g_assert_cmpuint (i, ==, 2);
 }
 
 int main (int argc, char **argv)