Convert InfoStore to TAILQ.

[somiaj]

Use TAILQ instead of a linked list for InfoStore. This also reduces looping over the list multiple times in some situations.

This fixes #993.

[ThomasAdam]

Hi @somiaj

I think this looks good overall. I would apply the following diff on top though:

diff --git a/fvwm/infostore.c b/fvwm/infostore.c
index 07cb5aafd..315b33127 100644
--- a/fvwm/infostore.c
+++ b/fvwm/infostore.c
@@ -83,7 +83,7 @@ void insert_metainfo(char *key, char *value)
 
 static void delete_metainfo(const char *key)
 {
-       MetaInfo *mi;
+       MetaInfo *mi = NULL;
 
        TAILQ_FOREACH(mi, &meta_info_q, entry)
        {
@@ -119,22 +119,17 @@ inline char *get_metainfo_value(const char *key)
 void print_infostore(void)
 {
        MetaInfo *mi;
-       bool not_found = 1;
-
-       fvwm_debug(__func__, "Current items in infostore (key, value):\n\n");
-       TAILQ_FOREACH(mi, &meta_info_q, entry)
-       {
-               fvwm_debug(__func__, "%s\t%s\n", mi->key, mi->value);
-               not_found = 0;
-       }
 
-       if (not_found)
-       {
+       if (TAILQ_EMPTY(&meta_info_q)) {
                fvwm_debug(__func__,
                           "No items are currently stored in the infostore.\n");
                return;
        }
 
+       fvwm_debug(__func__, "Current items in infostore (key, value):\n\n");
+       TAILQ_FOREACH(mi, &meta_info_q, entry)
+               fvwm_debug(__func__, "%s\t%s", mi->key, mi->value);
+
        return;
 }

[somiaj]

Patched applied, thanks.