Minor cleanup of the Mass Storage bootloader VirtualFAT code.

[pub/USBasp.git] / Bootloaders / MassStorage / Lib / VirtualFAT.c

diff --git a/Bootloaders/MassStorage/Lib/VirtualFAT.c b/Bootloaders/MassStorage/Lib/VirtualFAT.c
index e50014b..569b754 100644 (file)
--- a/Bootloaders/MassStorage/Lib/VirtualFAT.c
+++ b/Bootloaders/MassStorage/Lib/VirtualFAT.c
@@ -72,7 +72,7 @@ static const FATBootBlock_t BootBlock =
        };
 
 /** FAT 8.3 style directory entry, for the virtual FLASH contents file. */
-FATDirectoryEntry_t FirmwareFileEntries[] =
+static FATDirectoryEntry_t FirmwareFileEntries[] =
        {
                /* Root volume label entry; disk label is contained in the Filename and
                 * Extension fields (concatenated) with a special attribute flag - other
@@ -143,7 +143,7 @@ FATDirectoryEntry_t FirmwareFileEntries[] =
  *  are (usually?) replaced using the original file's physical sectors. On Linux
  *  file replacements are performed with an offset.
  */
-uint16_t FileStartBlock = DISK_BLOCK_DataStartBlock;
+static uint16_t FileStartBlock = DISK_BLOCK_DataStartBlock;
 
 
 /** Updates a FAT12 cluster entry in the FAT file table with the specified next
@@ -252,19 +252,30 @@ void VirtualFAT_WriteBlock(const uint16_t BlockNumber)
        Endpoint_Read_Stream_LE(BlockBuffer, sizeof(BlockBuffer), NULL);
        Endpoint_ClearOUT();
 
-       if (BlockNumber == DISK_BLOCK_RootFilesBlock)
+       switch (BlockNumber)
        {
-               /* Copy over the updated directory entries */
-               memcpy(FirmwareFileEntries, BlockBuffer, sizeof(FirmwareFileEntries));
+               case DISK_BLOCK_BootBlock:
+               case DISK_BLOCK_FATBlock1:
+               case DISK_BLOCK_FATBlock2:
+                       /* Ignore writes to the boot and FAT blocks */
 
-               /* Save the new firmware file block offset so the written and read file
-                * contents can be correctly mapped to the device's FLASH pages */
-               FileStartBlock = DISK_BLOCK_DataStartBlock +
-                                (FirmwareFileEntries[DISK_FILE_ENTRY_FirmwareMSDOS].MSDOS_File.StartingCluster - 2) * SECTOR_PER_CLUSTER;
-       }
-       else
-       {
-               ReadWriteFirmwareFileBlock(BlockNumber, BlockBuffer, false);
+                       break;
+
+               case DISK_BLOCK_RootFilesBlock:
+                       /* Copy over the updated directory entries */
+                       memcpy(FirmwareFileEntries, BlockBuffer, sizeof(FirmwareFileEntries));
+
+                       /* Save the new firmware file block offset so the written and read file
+                        * contents can be correctly mapped to the device's FLASH pages */
+                       FileStartBlock = DISK_BLOCK_DataStartBlock +
+                                        (FirmwareFileEntries[DISK_FILE_ENTRY_FirmwareMSDOS].MSDOS_File.StartingCluster - 2) * SECTOR_PER_CLUSTER;
+
+                       break;
+
+               default:
+                       ReadWriteFirmwareFileBlock(BlockNumber, BlockBuffer, false);
+
+                       break;
        }
 }
 
@@ -317,7 +328,7 @@ void VirtualFAT_ReadBlock(const uint16_t BlockNumber)
 
                        break;
 
-               default: /* Blocks 4 onwards: Data allocation section */
+               default:
                        ReadWriteFirmwareFileBlock(BlockNumber, BlockBuffer, true);
 
                        break;