Dircache: Don't expose struct dircache_entry and pointers into the cache, use IDs instead.

Only integer IDs are exposed from dircache with this. This way the cache is isolated from other modules.
This is needed for my buflib gsoc project.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30038 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 17 insertions, 40 deletions

diff --git a/apps/tagcache.c b/apps/tagcache.c
index 080f4198c3..c5a8dcbae5 100644
--- a/apps/tagcache.c
+++ b/apps/tagcache.c
@@ -383,8 +383,9 @@ static bool do_timed_yield(void)
 #endif
 
 #if defined(HAVE_TC_RAMCACHE) && defined(HAVE_DIRCACHE)
-static long find_entry_ram(const char *filename,
-                           const struct dircache_entry *dc)
+/* find the ramcache entry corresponding to the file indicated by
+ * filename and dc (it's corresponding dircache id). */
+static long find_entry_ram(const char *filename, int dc)
 {
     static long last_pos = 0;
     int i;
@@ -393,10 +394,10 @@ static long find_entry_ram(const char *filename,
     if (!tc_stat.ramcache)
         return -1;
 
-    if (dc == NULL)
-        dc = dircache_get_entry_ptr(filename);
+    if (dc < 0)
+        dc = dircache_get_entry_id(filename);
     
-    if (dc == NULL)
+    if (dc < 0)
     {
         logf("tagcache: file not found.");
         return -1;
@@ -411,7 +412,7 @@ static long find_entry_ram(const char *filename,
     
     for (; i < current_tcmh.tch.entry_count; i++)
     {
-        if (hdr->indices[i].tag_seek[tag_filename] == (long)dc)
+        if (hdr->indices[i].tag_seek[tag_filename] == dc)
         {
             last_pos = MAX(0, i - 3);
             return i;
@@ -539,7 +540,7 @@ static int find_index(const char *filename)
     
 #if defined(HAVE_TC_RAMCACHE) && defined(HAVE_DIRCACHE)
     if (tc_stat.ramcache && is_dircache_intact())
-        idx_id = find_entry_ram(filename, NULL);
+        idx_id = find_entry_ram(filename, -1);
 #endif
     
     if (idx_id < 0)
@@ -723,8 +724,8 @@ static bool retrieve(struct tagcache_search *tcs, struct index_entry *idx,
         if (tag == tag_filename && (idx->flag & FLAG_DIRCACHE)
             && is_dircache_intact())
         {
-            dircache_copy_path((struct dircache_entry *)seek,
-                               buf, size);
+            /* for tag_filename, seek is a dircache index */
+            dircache_copy_path(seek, buf, size);
             return true;
         }
         else
@@ -1481,8 +1482,7 @@ static bool get_next(struct tagcache_search *tcs)
         if (tcs->type == tag_filename && (flag & FLAG_DIRCACHE)
             && is_dircache_intact())
         {
-            size_t len = dircache_copy_path((struct dircache_entry *)tcs->position,
-                               buf, sizeof buf);
+            size_t len = dircache_copy_path(tcs->position, buf, sizeof buf);
             tcs->result_len = len + 1;
             tcs->result = buf;
             tcs->ramresult = false;
@@ -1599,29 +1599,6 @@ static bool update_master_header(void)
     return true;
 }
 
-#if 0
-
-void tagcache_modify(struct tagcache_search *tcs, int type, const char *text)
-{
-    struct tagentry *entry;
-    
-    if (tcs->type != tag_title)
-        return ;
-
-    /* We will need reserve buffer for this. */
-    if (tcs->ramcache)
-    {
-        struct tagfile_entry *ep;
-
-        ep = (struct tagfile_entry *)&hdr->tags[tcs->type][tcs->result_seek];
-        tcs->seek_list[tcs->seek_list_count];
-    }
-
-    entry = find_entry_ram();
-    
-}
-#endif
-
 void tagcache_search_finish(struct tagcache_search *tcs)
 {
     int i;
@@ -1677,7 +1654,7 @@ bool tagcache_fill_tags(struct mp3entry *id3, const char *filename)
         return false;
     
     /* Find the corresponding entry in tagcache. */
-    idx_id = find_entry_ram(filename, NULL);
+    idx_id = find_entry_ram(filename, -1);
     if (idx_id < 0)
         return false;
     
@@ -1761,7 +1738,7 @@ static int check_if_empty(char **tag)
 static void __attribute__ ((noinline)) add_tagcache(char *path,
                                                     unsigned long mtime
 #if defined(HAVE_TC_RAMCACHE) && defined(HAVE_DIRCACHE)
-                                                    ,const struct dircache_entry *dc
+                                                    ,int dc
 #endif
                                                    )
 {
@@ -4017,7 +3994,7 @@ static bool load_tagcache(void)
             if (tag == tag_filename)
             {
 # ifdef HAVE_DIRCACHE
-                const struct dircache_entry *dc;
+                int dc;
 # endif
                 
                 // FIXME: This is wrong!
@@ -4064,8 +4041,8 @@ static bool load_tagcache(void)
 # ifdef HAVE_DIRCACHE
                 if (dircache_is_enabled())
                 {
-                    dc = dircache_get_entry_ptr(buf);
-                    if (dc == NULL)
+                    dc = dircache_get_entry_id(buf);
+                    if (dc < 0)
                     {
                         logf("Entry no longer valid.");
                         logf("-> %s", buf);
@@ -4075,7 +4052,7 @@ static bool load_tagcache(void)
                     }
 
                     idx->flag |= FLAG_DIRCACHE;
-                    idx->tag_seek[tag_filename] = (long)dc;
+                    idx->tag_seek[tag_filename] = dc;
                 }
                 else
 # endif