GSoC/Buflib: Add buflib memory alocator to the core.

The buflib memory allocator is handle based and can free and
compact, move or resize memory on demand. This allows to effeciently
allocate memory dynamically without an MMU, by avoiding fragmentation
through memory compaction.

This patch adds the buflib library to the core, along with
convinience wrappers to omit the context parameter. Compaction is
not yet enabled, but will be in a later patch. Therefore, this acts as a
replacement for buffer_alloc/buffer_get_buffer() with the benifit of a debug
menu.

See buflib.h for some API documentation.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30380 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 15 insertions, 8 deletions

diff --git a/firmware/common/dircache.c b/firmware/common/dircache.c
index f47e65e428..334801ce57 100644
--- a/firmware/common/dircache.c
+++ b/firmware/common/dircache.c
@@ -38,7 +38,7 @@
 #include "kernel.h"
 #include "usb.h"
 #include "file.h"
-#include "buffer.h"
+#include "core_alloc.h"
 #include "dir.h"
 #include "storage.h"
 #if CONFIG_RTC
@@ -57,6 +57,8 @@
 #else
 #define MAX_OPEN_DIRS 8
 #endif
+static DIR_CACHED opendirs[MAX_OPEN_DIRS];
+static char       opendir_dnames[MAX_OPEN_DIRS][MAX_PATH];
 
 #define MAX_PENDING_BINDINGS 2
 struct fdbind_queue {
@@ -571,7 +573,8 @@ int dircache_load(void)
     }
     
     allocated_size = maindata.size + DIRCACHE_RESERVE;
-    dircache_root = buffer_alloc(allocated_size);
+    int handle = core_alloc("dircache", allocated_size);
+    dircache_root = core_get_data(handle);
     /* needs to be struct-size aligned so that the pointer arithmetic below works */
     ALIGN_BUFFER(dircache_root, allocated_size, sizeof(struct dircache_entry));
     entry_count = maindata.entry_count;
@@ -814,6 +817,7 @@ static void generate_dot_d_names(void)
     strcpy(dot, ".");
     strcpy(dotdot, "..");
 }
+
 /**
  * Start scanning the disk to build the dircache.
  * Either transparent or non-transparent build method is used.
@@ -841,11 +845,13 @@ int dircache_build(int last_size)
         queue_post(&dircache_queue, DIRCACHE_BUILD, 0);
         return 2;
     }
-    
+
     if (last_size > DIRCACHE_RESERVE && last_size < DIRCACHE_LIMIT )
     {
+        int handle;
         allocated_size = last_size + DIRCACHE_RESERVE;
-        dircache_root = buffer_alloc(allocated_size);
+        handle = core_alloc("dircache", allocated_size);
+        dircache_root = core_get_data(handle);
         ALIGN_BUFFER(dircache_root, allocated_size, sizeof(struct dircache_entry));
         d_names_start = d_names_end = ((char*)dircache_root)+allocated_size-1;
         dircache_size = 0;
@@ -863,7 +869,8 @@ int dircache_build(int last_size)
      * after generation the buffer will be compacted with DIRCACHE_RESERVE
      * free bytes inbetween */
     size_t got_size;
-    char* buf = buffer_get_buffer(&got_size);
+    int handle = core_alloc_maximum("dircache", &got_size, NULL);
+    char* buf = core_get_data(handle);
     dircache_root = (struct dircache_entry*)ALIGN_UP(buf,
                                                 sizeof(struct dircache_entry));
     d_names_start = d_names_end = buf + got_size - 1;
@@ -902,11 +909,11 @@ int dircache_build(int last_size)
     allocated_size = (d_names_end - buf);
     reserve_used = 0;
 
-    buffer_release_buffer(allocated_size);
+    core_shrink(handle, dircache_root, allocated_size);
     return res;
 fail:
     dircache_disable();
-    buffer_release_buffer(0);
+    core_free(handle);
     return res;
 }
 
@@ -942,7 +949,7 @@ void dircache_init(void)
     memset(opendirs, 0, sizeof(opendirs));
     for (i = 0; i < MAX_OPEN_DIRS; i++)
     {
-        opendirs[i].theent.d_name = buffer_alloc(MAX_PATH);
+        opendirs[i].theent.d_name = opendir_dnames[i];
     }
     
     queue_init(&dircache_queue, true);