Improve the label completion hash table usage.

Move the hash table inside the Context.  Hook message arrival/deletion
to update the label hash.

Change the label hash to strdup keys.

Use hash_find_elem when updating the counter, to reduce unnecessary
add/delete operations.

1 files changed, 2 insertions, 0 deletions

diff --git a/mbox.c b/mbox.c
index 37f426d8..74affebc 100644
--- a/mbox.c
+++ b/mbox.c
@@ -1198,6 +1198,7 @@ int mutt_reopen_mailbox (CONTEXT *ctx, int *index_hint)
     hash_destroy (&ctx->id_hash, NULL);
   if (ctx->subj_hash)
     hash_destroy (&ctx->subj_hash, NULL);
+  hash_destroy (&ctx->label_hash, NULL);
   mutt_clear_threads (ctx);
   FREE (&ctx->v2r);
   if (ctx->readonly)
@@ -1225,6 +1226,7 @@ int mutt_reopen_mailbox (CONTEXT *ctx, int *index_hint)
   ctx->changed = 0;
   ctx->id_hash = NULL;
   ctx->subj_hash = NULL;
+  mutt_make_label_hash (ctx);
 
   switch (ctx->magic)
   {