Changeset 291 for soft/giet_vm/giet_fat32/fat32.h

Timestamp:

Feb 13, 2014, 3:29:33 PM (11 years ago)

Author:

devigne

Message:

• Added fat_allocate function to enlarge the size of a file.

• Recovery of FS_INFO in fat_init function, FS_INFO contains important information for the allocation of new clusters such as the last cluster allocated and the number of still free cluster.

• Added update functions :
  • For FAT : update the chaining of clusters after allocation.
  • For DIR_ENTRY : update a field into a DIR_ENTRY, eg FILE_SIZE field after a write.
  • For FS_INFO : after allocation we must update the last cluster allocated and number of free cluster fields.

File:

• soft/giet_vm/giet_fat32/fat32.h (modified) (4 diffs)

soft/giet_vm/giet_fat32/fat32.h

@@ -67 +67 @@
 #define FS_SIGNATURE_POSITION_2           484 , 4
 #define FS_SIGNATURE_POSITION_3           508 , 4  
-#define FS_FREE_CLUSTER                   492 , 4
-#define FS_FREE_CLUSTER_HINT              496 , 4
+#define FS_FREE_CLUSTER                   488 , 4
+#define FS_FREE_CLUSTER_HINT              492 , 4
 /***************************************************************************************/
 
@@ -98 +98 @@
 /***************************************************************************************/
 
-/***********************  DIR_ATTR values  (attributes) ********************************/  
+/***********************  DIR_ATTR values  (attributes) ********************************/
 #define ATTR_READ_ONLY          0x01
 #define ATTR_HIDDEN             0x02
@@ -128 +128 @@
    unsigned int  first_cluster;             // first cluster index in partition
    unsigned int  file_size;                 // number of bytes    
+   unsigned int  lba_dir_entry;             // lba of dir_entry for an open file 
    char          name[244];                 // pathname
 }  file_desc_t;
@@ -146 +147 @@
     unsigned int    data_lba;                // lba of first data sector  
     unsigned int    cache_lba;               // lba of sector loaded in fat_cache
+    unsigned int    last_cluster_allocated;  // Last known cluster allocated
+    unsigned int    number_free_cluster;     // number of free clusters
+    unsigned int    fs_info_lba;             // lba of fs_info
 } fat32_fs_t;
 /***************************************************************************************/