]> git.kernelconcepts.de Git - karo-tx-uboot.git/commitdiff
FAT: Add FAT write feature
authorDonggeun Kim <dg77.kim@samsung.com>
Mon, 24 Oct 2011 21:15:28 +0000 (21:15 +0000)
committerWolfgang Denk <wd@denx.de>
Wed, 26 Oct 2011 19:40:44 +0000 (21:40 +0200)
In some cases, saving data in RAM as a file with FAT format is required.
This patch allows the file to be written in FAT formatted partition.

The usage is similar with reading a file.
First, fat_register_device function is called before file_fat_write function
in order to set target partition.
Then, file_fat_write function is invoked with desired file name,
start ram address for writing data, and file size.

Signed-off-by: Donggeun Kim <dg77.kim@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
README
fs/fat/Makefile
fs/fat/fat.c
fs/fat/fat_write.c [new file with mode: 0644]
include/fat.h

diff --git a/README b/README
index a3b62e14dbb0827d0de52ba7ed7f4b73038e22c3..a1910dcfea0af9418851401fe1412e85ed9177ec 100644 (file)
--- a/README
+++ b/README
@@ -1175,6 +1175,11 @@ The following options need to be configured:
                to disable the command chpart. This is the default when you
                have not defined a custom partition
 
+- FAT(File Allocation Table) filesystem write function support:
+               CONFIG_FAT_WRITE
+               Support for saving memory data as a file
+               in FAT formatted partition
+
 - Keyboard Support:
                CONFIG_ISA_KEYBOARD
 
index 93b6f07389637e34c3e900b7e3b0bddc6628f9c5..9635d36fcf9caa4f2023c94b9a48bd08ec13517b 100644 (file)
@@ -25,6 +25,7 @@ LIB   = $(obj)libfat.o
 
 AOBJS  =
 COBJS-$(CONFIG_CMD_FAT)        := fat.o
+COBJS-$(CONFIG_FAT_WRITE):= fat_write.o
 
 ifndef CONFIG_SPL_BUILD
 COBJS-$(CONFIG_CMD_FAT)        += file.o
index 756ac64a8b7b98287788702728134947f22b15ce..7cf173caaaae7b1f0f6c96de6e3dc1105ce5accb 100644 (file)
@@ -46,6 +46,7 @@ static void downcase (char *str)
 static block_dev_desc_t *cur_dev = NULL;
 
 static unsigned long part_offset = 0;
+static unsigned long part_size;
 
 static int cur_part = 1;
 
@@ -99,6 +100,7 @@ int fat_register_device (block_dev_desc_t * dev_desc, int part_no)
        if (!get_partition_info(dev_desc, part_no, &info)) {
                part_offset = info.start;
                cur_part = part_no;
+               part_size = info.size;
        } else if ((strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3) == 0) ||
                   (strncmp((char *)&buffer[DOS_FS32_TYPE_OFFSET], "FAT32", 5) == 0)) {
                /* ok, we assume we are on a PBR only */
diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c
new file mode 100644 (file)
index 0000000..4f1772f
--- /dev/null
@@ -0,0 +1,1090 @@
+/*
+ * fat_write.c
+ *
+ * R/W (V)FAT 12/16/32 filesystem implementation by Donggeun Kim
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <command.h>
+#include <config.h>
+#include <fat.h>
+#include <asm/byteorder.h>
+#include <part.h>
+#include "fat.c"
+
+static void uppercase(char *str, int len)
+{
+       int i;
+
+       for (i = 0; i < len; i++) {
+               TOUPPER(*str);
+               str++;
+       }
+}
+
+static int total_sector;
+static int disk_write(__u32 startblock, __u32 getsize, __u8 *bufptr)
+{
+       if (cur_dev == NULL)
+               return -1;
+
+       if (startblock + getsize > total_sector) {
+               printf("error: overflow occurs\n");
+               return -1;
+       }
+
+       startblock += part_offset;
+
+       if (cur_dev->block_read) {
+               return cur_dev->block_write(cur_dev->dev, startblock, getsize,
+                                          (unsigned long *) bufptr);
+       }
+       return -1;
+}
+
+/*
+ * Set short name in directory entry
+ */
+static void set_name(dir_entry *dirent, const char *filename)
+{
+       char s_name[VFAT_MAXLEN_BYTES];
+       char *period;
+       int period_location, len, i, ext_num;
+
+       if (filename == NULL)
+               return;
+
+       len = strlen(filename);
+       if (len == 0)
+               return;
+
+       memcpy(s_name, filename, len);
+       uppercase(s_name, len);
+
+       period = strchr(s_name, '.');
+       if (period == NULL) {
+               period_location = len;
+               ext_num = 0;
+       } else {
+               period_location = period - s_name;
+               ext_num = len - period_location - 1;
+       }
+
+       /* Pad spaces when the length of file name is shorter than eight */
+       if (period_location < 8) {
+               memcpy(dirent->name, s_name, period_location);
+               for (i = period_location; i < 8; i++)
+                       dirent->name[i] = ' ';
+       } else if (period_location == 8) {
+               memcpy(dirent->name, s_name, period_location);
+       } else {
+               memcpy(dirent->name, s_name, 6);
+               dirent->name[6] = '~';
+               dirent->name[7] = '1';
+       }
+
+       if (ext_num < 3) {
+               memcpy(dirent->ext, s_name + period_location + 1, ext_num);
+               for (i = ext_num; i < 3; i++)
+                       dirent->ext[i] = ' ';
+       } else
+               memcpy(dirent->ext, s_name + period_location + 1, 3);
+
+       debug("name : %s\n", dirent->name);
+       debug("ext : %s\n", dirent->ext);
+}
+
+/*
+ * Write fat buffer into block device
+ */
+static int flush_fat_buffer(fsdata *mydata)
+{
+       int getsize = FATBUFBLOCKS;
+       __u32 fatlength = mydata->fatlength;
+       __u8 *bufptr = mydata->fatbuf;
+       __u32 startblock = mydata->fatbufnum * FATBUFBLOCKS;
+
+       fatlength *= mydata->sect_size;
+       startblock += mydata->fat_sect;
+
+       if (getsize > fatlength)
+               getsize = fatlength;
+
+       /* Write FAT buf */
+       if (disk_write(startblock, getsize, bufptr) < 0) {
+               debug("error: writing FAT blocks\n");
+               return -1;
+       }
+
+       return 0;
+}
+
+/*
+ * Get the entry at index 'entry' in a FAT (12/16/32) table.
+ * On failure 0x00 is returned.
+ * When bufnum is changed, write back the previous fatbuf to the disk.
+ */
+static __u32 get_fatent_value(fsdata *mydata, __u32 entry)
+{
+       __u32 bufnum;
+       __u32 off16, offset;
+       __u32 ret = 0x00;
+       __u16 val1, val2;
+
+       switch (mydata->fatsize) {
+       case 32:
+               bufnum = entry / FAT32BUFSIZE;
+               offset = entry - bufnum * FAT32BUFSIZE;
+               break;
+       case 16:
+               bufnum = entry / FAT16BUFSIZE;
+               offset = entry - bufnum * FAT16BUFSIZE;
+               break;
+       case 12:
+               bufnum = entry / FAT12BUFSIZE;
+               offset = entry - bufnum * FAT12BUFSIZE;
+               break;
+
+       default:
+               /* Unsupported FAT size */
+               return ret;
+       }
+
+       debug("FAT%d: entry: 0x%04x = %d, offset: 0x%04x = %d\n",
+              mydata->fatsize, entry, entry, offset, offset);
+
+       /* Read a new block of FAT entries into the cache. */
+       if (bufnum != mydata->fatbufnum) {
+               int getsize = FATBUFBLOCKS;
+               __u8 *bufptr = mydata->fatbuf;
+               __u32 fatlength = mydata->fatlength;
+               __u32 startblock = bufnum * FATBUFBLOCKS;
+
+               if (getsize > fatlength)
+                       getsize = fatlength;
+
+               fatlength *= mydata->sect_size; /* We want it in bytes now */
+               startblock += mydata->fat_sect; /* Offset from start of disk */
+
+               /* Write back the fatbuf to the disk */
+               if (mydata->fatbufnum != -1) {
+                       if (flush_fat_buffer(mydata) < 0)
+                               return -1;
+               }
+
+               if (disk_read(startblock, getsize, bufptr) < 0) {
+                       debug("Error reading FAT blocks\n");
+                       return ret;
+               }
+               mydata->fatbufnum = bufnum;
+       }
+
+       /* Get the actual entry from the table */
+       switch (mydata->fatsize) {
+       case 32:
+               ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
+               break;
+       case 16:
+               ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
+               break;
+       case 12:
+               off16 = (offset * 3) / 4;
+
+               switch (offset & 0x3) {
+               case 0:
+                       ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
+                       ret &= 0xfff;
+                       break;
+               case 1:
+                       val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
+                       val1 &= 0xf000;
+                       val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
+                       val2 &= 0x00ff;
+                       ret = (val2 << 4) | (val1 >> 12);
+                       break;
+               case 2:
+                       val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
+                       val1 &= 0xff00;
+                       val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
+                       val2 &= 0x000f;
+                       ret = (val2 << 8) | (val1 >> 8);
+                       break;
+               case 3:
+                       ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
+                       ret = (ret & 0xfff0) >> 4;
+                       break;
+               default:
+                       break;
+               }
+               break;
+       }
+       debug("FAT%d: ret: %08x, entry: %08x, offset: %04x\n",
+              mydata->fatsize, ret, entry, offset);
+
+       return ret;
+}
+
+#ifdef CONFIG_SUPPORT_VFAT
+/*
+ * Set the file name information from 'name' into 'slotptr',
+ */
+static int str2slot(dir_slot *slotptr, const char *name, int *idx)
+{
+       int j, end_idx = 0;
+
+       for (j = 0; j <= 8; j += 2) {
+               if (name[*idx] == 0x00) {
+                       slotptr->name0_4[j] = 0;
+                       slotptr->name0_4[j + 1] = 0;
+                       end_idx++;
+                       goto name0_4;
+               }
+               slotptr->name0_4[j] = name[*idx];
+               (*idx)++;
+               end_idx++;
+       }
+       for (j = 0; j <= 10; j += 2) {
+               if (name[*idx] == 0x00) {
+                       slotptr->name5_10[j] = 0;
+                       slotptr->name5_10[j + 1] = 0;
+                       end_idx++;
+                       goto name5_10;
+               }
+               slotptr->name5_10[j] = name[*idx];
+               (*idx)++;
+               end_idx++;
+       }
+       for (j = 0; j <= 2; j += 2) {
+               if (name[*idx] == 0x00) {
+                       slotptr->name11_12[j] = 0;
+                       slotptr->name11_12[j + 1] = 0;
+                       end_idx++;
+                       goto name11_12;
+               }
+               slotptr->name11_12[j] = name[*idx];
+               (*idx)++;
+               end_idx++;
+       }
+
+       if (name[*idx] == 0x00)
+               return 1;
+
+       return 0;
+/* Not used characters are filled with 0xff 0xff */
+name0_4:
+       for (; end_idx < 5; end_idx++) {
+               slotptr->name0_4[end_idx * 2] = 0xff;
+               slotptr->name0_4[end_idx * 2 + 1] = 0xff;
+       }
+       end_idx = 5;
+name5_10:
+       end_idx -= 5;
+       for (; end_idx < 6; end_idx++) {
+               slotptr->name5_10[end_idx * 2] = 0xff;
+               slotptr->name5_10[end_idx * 2 + 1] = 0xff;
+       }
+       end_idx = 11;
+name11_12:
+       end_idx -= 11;
+       for (; end_idx < 2; end_idx++) {
+               slotptr->name11_12[end_idx * 2] = 0xff;
+               slotptr->name11_12[end_idx * 2 + 1] = 0xff;
+       }
+
+       return 1;
+}
+
+static int is_next_clust(fsdata *mydata, dir_entry *dentptr);
+static void flush_dir_table(fsdata *mydata, dir_entry **dentptr);
+
+/*
+ * Fill dir_slot entries with appropriate name, id, and attr
+ * The real directory entry is returned by 'dentptr'
+ */
+static void
+fill_dir_slot(fsdata *mydata, dir_entry **dentptr, const char *l_name)
+{
+       dir_slot *slotptr = (dir_slot *)get_vfatname_block;
+       __u8 counter, checksum;
+       int idx = 0, ret;
+       char s_name[16];
+
+       /* Get short file name and checksum value */
+       strncpy(s_name, (*dentptr)->name, 16);
+       checksum = mkcksum(s_name);
+
+       do {
+               memset(slotptr, 0x00, sizeof(dir_slot));
+               ret = str2slot(slotptr, l_name, &idx);
+               slotptr->id = ++counter;
+               slotptr->attr = ATTR_VFAT;
+               slotptr->alias_checksum = checksum;
+               slotptr++;
+       } while (ret == 0);
+
+       slotptr--;
+       slotptr->id |= LAST_LONG_ENTRY_MASK;
+
+       while (counter >= 1) {
+               if (is_next_clust(mydata, *dentptr)) {
+                       /* A new cluster is allocated for directory table */
+                       flush_dir_table(mydata, dentptr);
+               }
+               memcpy(*dentptr, slotptr, sizeof(dir_slot));
+               (*dentptr)++;
+               slotptr--;
+               counter--;
+       }
+
+       if (is_next_clust(mydata, *dentptr)) {
+               /* A new cluster is allocated for directory table */
+               flush_dir_table(mydata, dentptr);
+       }
+}
+
+static __u32 dir_curclust;
+
+/*
+ * Extract the full long filename starting at 'retdent' (which is really
+ * a slot) into 'l_name'. If successful also copy the real directory entry
+ * into 'retdent'
+ * If additional adjacent cluster for directory entries is read into memory,
+ * then 'get_vfatname_block' is copied into 'get_dentfromdir_block' and
+ * the location of the real directory entry is returned by 'retdent'
+ * Return 0 on success, -1 otherwise.
+ */
+static int
+get_long_file_name(fsdata *mydata, int curclust, __u8 *cluster,
+             dir_entry **retdent, char *l_name)
+{
+       dir_entry *realdent;
+       dir_slot *slotptr = (dir_slot *)(*retdent);
+       dir_slot *slotptr2 = NULL;
+       __u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ?
+                                                       PREFETCH_BLOCKS :
+                                                       mydata->clust_size);
+       __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
+       int idx = 0, cur_position = 0;
+
+       if (counter > VFAT_MAXSEQ) {
+               debug("Error: VFAT name is too long\n");
+               return -1;
+       }
+
+       while ((__u8 *)slotptr < buflimit) {
+               if (counter == 0)
+                       break;
+               if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
+                       return -1;
+               slotptr++;
+               counter--;
+       }
+
+       if ((__u8 *)slotptr >= buflimit) {
+               if (curclust == 0)
+                       return -1;
+               curclust = get_fatent_value(mydata, dir_curclust);
+               if (CHECK_CLUST(curclust, mydata->fatsize)) {
+                       debug("curclust: 0x%x\n", curclust);
+                       printf("Invalid FAT entry\n");
+                       return -1;
+               }
+
+               dir_curclust = curclust;
+
+               if (get_cluster(mydata, curclust, get_vfatname_block,
+                               mydata->clust_size * mydata->sect_size) != 0) {
+                       debug("Error: reading directory block\n");
+                       return -1;
+               }
+
+               slotptr2 = (dir_slot *)get_vfatname_block;
+               while (counter > 0) {
+                       if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
+                           & 0xff) != counter)
+                               return -1;
+                       slotptr2++;
+                       counter--;
+               }
+
+               /* Save the real directory entry */
+               realdent = (dir_entry *)slotptr2;
+               while ((__u8 *)slotptr2 > get_vfatname_block) {
+                       slotptr2--;
+                       slot2str(slotptr2, l_name, &idx);
+               }
+       } else {
+               /* Save the real directory entry */
+               realdent = (dir_entry *)slotptr;
+       }
+
+       do {
+               slotptr--;
+               if (slot2str(slotptr, l_name, &idx))
+                       break;
+       } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
+
+       l_name[idx] = '\0';
+       if (*l_name == DELETED_FLAG)
+               *l_name = '\0';
+       else if (*l_name == aRING)
+               *l_name = DELETED_FLAG;
+       downcase(l_name);
+
+       /* Return the real directory entry */
+       *retdent = realdent;
+
+       if (slotptr2) {
+               memcpy(get_dentfromdir_block, get_vfatname_block,
+                       mydata->clust_size * mydata->sect_size);
+               cur_position = (__u8 *)realdent - get_vfatname_block;
+               *retdent = (dir_entry *) &get_dentfromdir_block[cur_position];
+       }
+
+       return 0;
+}
+
+#endif
+
+/*
+ * Set the entry at index 'entry' in a FAT (16/32) table.
+ */
+static int set_fatent_value(fsdata *mydata, __u32 entry, __u32 entry_value)
+{
+       __u32 bufnum, offset;
+
+       switch (mydata->fatsize) {
+       case 32:
+               bufnum = entry / FAT32BUFSIZE;
+               offset = entry - bufnum * FAT32BUFSIZE;
+               break;
+       case 16:
+               bufnum = entry / FAT16BUFSIZE;
+               offset = entry - bufnum * FAT16BUFSIZE;
+               break;
+       default:
+               /* Unsupported FAT size */
+               return -1;
+       }
+
+       /* Read a new block of FAT entries into the cache. */
+       if (bufnum != mydata->fatbufnum) {
+               int getsize = FATBUFBLOCKS;
+               __u8 *bufptr = mydata->fatbuf;
+               __u32 fatlength = mydata->fatlength;
+               __u32 startblock = bufnum * FATBUFBLOCKS;
+
+               fatlength *= mydata->sect_size;
+               startblock += mydata->fat_sect;
+
+               if (getsize > fatlength)
+                       getsize = fatlength;
+
+               if (mydata->fatbufnum != -1) {
+                       if (flush_fat_buffer(mydata) < 0)
+                               return -1;
+               }
+
+               if (disk_read(startblock, getsize, bufptr) < 0) {
+                       debug("Error reading FAT blocks\n");
+                       return -1;
+               }
+               mydata->fatbufnum = bufnum;
+       }
+
+       /* Set the actual entry */
+       switch (mydata->fatsize) {
+       case 32:
+               ((__u32 *) mydata->fatbuf)[offset] = cpu_to_le32(entry_value);
+               break;
+       case 16:
+               ((__u16 *) mydata->fatbuf)[offset] = cpu_to_le16(entry_value);
+               break;
+       default:
+               return -1;
+       }
+
+       return 0;
+}
+
+/*
+ * Determine the entry value at index 'entry' in a FAT (16/32) table
+ */
+static __u32 determine_fatent(fsdata *mydata, __u32 entry)
+{
+       __u32 next_fat, next_entry = entry + 1;
+
+       while (1) {
+               next_fat = get_fatent_value(mydata, next_entry);
+               if (next_fat == 0) {
+                       set_fatent_value(mydata, entry, next_entry);
+                       break;
+               }
+               next_entry++;
+       }
+       debug("FAT%d: entry: %08x, entry_value: %04x\n",
+              mydata->fatsize, entry, next_entry);
+
+       return next_entry;
+}
+
+/*
+ * Write at most 'size' bytes from 'buffer' into the specified cluster.
+ * Return 0 on success, -1 otherwise.
+ */
+static int
+set_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer,
+            unsigned long size)
+{
+       int idx = 0;
+       __u32 startsect;
+
+       if (clustnum > 0)
+               startsect = mydata->data_begin +
+                               clustnum * mydata->clust_size;
+       else
+               startsect = mydata->rootdir_sect;
+
+       debug("clustnum: %d, startsect: %d\n", clustnum, startsect);
+
+       if (disk_write(startsect, size / mydata->sect_size, buffer) < 0) {
+               debug("Error writing data\n");
+               return -1;
+       }
+
+       if (size % mydata->sect_size) {
+               __u8 tmpbuf[mydata->sect_size];
+
+               idx = size / mydata->sect_size;
+               buffer += idx * mydata->sect_size;
+               memcpy(tmpbuf, buffer, size % mydata->sect_size);
+
+               if (disk_write(startsect + idx, 1, tmpbuf) < 0) {
+                       debug("Error writing data\n");
+                       return -1;
+               }
+
+               return 0;
+       }
+
+       return 0;
+}
+
+/*
+ * Find the first empty cluster
+ */
+static int find_empty_cluster(fsdata *mydata)
+{
+       __u32 fat_val, entry = 3;
+
+       while (1) {
+               fat_val = get_fatent_value(mydata, entry);
+               if (fat_val == 0)
+                       break;
+               entry++;
+       }
+
+       return entry;
+}
+
+/*
+ * Write directory entries in 'get_dentfromdir_block' to block device
+ */
+static void flush_dir_table(fsdata *mydata, dir_entry **dentptr)
+{
+       int dir_newclust = 0;
+
+       if (set_cluster(mydata, dir_curclust,
+                   get_dentfromdir_block,
+                   mydata->clust_size * mydata->sect_size) != 0) {
+               printf("error: wrinting directory entry\n");
+               return;
+       }
+       dir_newclust = find_empty_cluster(mydata);
+       set_fatent_value(mydata, dir_curclust, dir_newclust);
+       if (mydata->fatsize == 32)
+               set_fatent_value(mydata, dir_newclust, 0xffffff8);
+       else if (mydata->fatsize == 16)
+               set_fatent_value(mydata, dir_newclust, 0xfff8);
+
+       dir_curclust = dir_newclust;
+
+       if (flush_fat_buffer(mydata) < 0)
+               return;
+
+       memset(get_dentfromdir_block, 0x00,
+               mydata->clust_size * mydata->sect_size);
+
+       *dentptr = (dir_entry *) get_dentfromdir_block;
+}
+
+/*
+ * Set empty cluster from 'entry' to the end of a file
+ */
+static int clear_fatent(fsdata *mydata, __u32 entry)
+{
+       __u32 fat_val;
+
+       while (1) {
+               fat_val = get_fatent_value(mydata, entry);
+               if (fat_val != 0)
+                       set_fatent_value(mydata, entry, 0);
+               else
+                       break;
+
+               if (fat_val == 0xfffffff || fat_val == 0xffff)
+                       break;
+
+               entry = fat_val;
+       }
+
+       /* Flush fat buffer */
+       if (flush_fat_buffer(mydata) < 0)
+               return -1;
+
+       return 0;
+}
+
+/*
+ * Write at most 'maxsize' bytes from 'buffer' into
+ * the file associated with 'dentptr'
+ * Return the number of bytes read or -1 on fatal errors.
+ */
+static int
+set_contents(fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
+             unsigned long maxsize)
+{
+       unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
+       unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
+       __u32 curclust = START(dentptr);
+       __u32 endclust = 0, newclust = 0;
+       unsigned long actsize;
+
+       debug("Filesize: %ld bytes\n", filesize);
+
+       if (maxsize > 0 && filesize > maxsize)
+               filesize = maxsize;
+
+       debug("%ld bytes\n", filesize);
+
+       actsize = bytesperclust;
+       endclust = curclust;
+       do {
+               /* search for consecutive clusters */
+               while (actsize < filesize) {
+                       newclust = determine_fatent(mydata, endclust);
+
+                       if ((newclust - 1) != endclust)
+                               goto getit;
+
+                       if (CHECK_CLUST(newclust, mydata->fatsize)) {
+                               debug("curclust: 0x%x\n", newclust);
+                               debug("Invalid FAT entry\n");
+                               return gotsize;
+                       }
+                       endclust = newclust;
+                       actsize += bytesperclust;
+               }
+               /* actsize >= file size */
+               actsize -= bytesperclust;
+               /* set remaining clusters */
+               if (set_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
+                       debug("error: writing cluster\n");
+                       return -1;
+               }
+
+               /* set remaining bytes */
+               gotsize += (int)actsize;
+               filesize -= actsize;
+               buffer += actsize;
+               actsize = filesize;
+
+               if (set_cluster(mydata, endclust, buffer, (int)actsize) != 0) {
+                       debug("error: writing cluster\n");
+                       return -1;
+               }
+               gotsize += actsize;
+
+               /* Mark end of file in FAT */
+               if (mydata->fatsize == 16)
+                       newclust = 0xffff;
+               else if (mydata->fatsize == 32)
+                       newclust = 0xfffffff;
+               set_fatent_value(mydata, endclust, newclust);
+
+               return gotsize;
+getit:
+               if (set_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
+                       debug("error: writing cluster\n");
+                       return -1;
+               }
+               gotsize += (int)actsize;
+               filesize -= actsize;
+               buffer += actsize;
+
+               if (CHECK_CLUST(curclust, mydata->fatsize)) {
+                       debug("curclust: 0x%x\n", curclust);
+                       debug("Invalid FAT entry\n");
+                       return gotsize;
+               }
+               actsize = bytesperclust;
+               curclust = endclust = newclust;
+       } while (1);
+}
+
+/*
+ * Fill dir_entry
+ */
+static void fill_dentry(fsdata *mydata, dir_entry *dentptr,
+       const char *filename, __u32 start_cluster, __u32 size, __u8 attr)
+{
+       if (mydata->fatsize == 32)
+               dentptr->starthi =
+                       cpu_to_le16((start_cluster & 0xffff0000) >> 16);
+       dentptr->start = cpu_to_le16(start_cluster & 0xffff);
+       dentptr->size = cpu_to_le32(size);
+
+       dentptr->attr = attr;
+
+       set_name(dentptr, filename);
+}
+
+/*
+ * Check whether adding a file makes the file system to
+ * exceed the size of the block device
+ * Return -1 when overflow occurs, otherwise return 0
+ */
+static int check_overflow(fsdata *mydata, __u32 clustnum, unsigned long size)
+{
+       __u32 startsect, sect_num;
+
+       if (clustnum > 0) {
+               startsect = mydata->data_begin +
+                               clustnum * mydata->clust_size;
+       } else {
+               startsect = mydata->rootdir_sect;
+       }
+
+       sect_num = size / mydata->sect_size;
+       if (size % mydata->sect_size)
+               sect_num++;
+
+       if (startsect + sect_num > total_sector)
+               return -1;
+
+       return 0;
+}
+
+/*
+ * Check if adding several entries exceed one cluster boundary
+ */
+static int is_next_clust(fsdata *mydata, dir_entry *dentptr)
+{
+       int cur_position;
+
+       cur_position = (__u8 *)dentptr - get_dentfromdir_block;
+
+       if (cur_position >= mydata->clust_size * mydata->sect_size)
+               return 1;
+       else
+               return 0;
+}
+
+static dir_entry *empty_dentptr;
+/*
+ * Find a directory entry based on filename or start cluster number
+ * If the directory entry is not found,
+ * the new position for writing a directory entry will be returned
+ */
+static dir_entry *find_directory_entry(fsdata *mydata, int startsect,
+       char *filename, dir_entry *retdent, __u32 start)
+{
+       __u16 prevcksum = 0xffff;
+       __u32 curclust = (startsect - mydata->data_begin) / mydata->clust_size;
+
+       debug("get_dentfromdir: %s\n", filename);
+
+       while (1) {
+               dir_entry *dentptr;
+
+               int i;
+
+               if (get_cluster(mydata, curclust, get_dentfromdir_block,
+                           mydata->clust_size * mydata->sect_size) != 0) {
+                       printf("Error: reading directory block\n");
+                       return NULL;
+               }
+
+               dentptr = (dir_entry *)get_dentfromdir_block;
+
+               dir_curclust = curclust;
+
+               for (i = 0; i < DIRENTSPERCLUST; i++) {
+                       char s_name[14], l_name[VFAT_MAXLEN_BYTES];
+
+                       l_name[0] = '\0';
+                       if (dentptr->name[0] == DELETED_FLAG) {
+                               dentptr++;
+                               if (is_next_clust(mydata, dentptr))
+                                       break;
+                               continue;
+                       }
+                       if ((dentptr->attr & ATTR_VOLUME)) {
+#ifdef CONFIG_SUPPORT_VFAT
+                               if ((dentptr->attr & ATTR_VFAT) &&
+                                   (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
+                                       prevcksum =
+                                       ((dir_slot *)dentptr)->alias_checksum;
+                                       get_long_file_name(mydata, curclust,
+                                                    get_dentfromdir_block,
+                                                    &dentptr, l_name);
+                                       debug("vfatname: |%s|\n", l_name);
+                               } else
+#endif
+                               {
+                                       /* Volume label or VFAT entry */
+                                       dentptr++;
+                                       if (is_next_clust(mydata, dentptr))
+                                               break;
+                                       continue;
+                               }
+                       }
+                       if (dentptr->name[0] == 0) {
+                               debug("Dentname == NULL - %d\n", i);
+                               empty_dentptr = dentptr;
+                               return NULL;
+                       }
+
+                       get_name(dentptr, s_name);
+
+                       if (strcmp(filename, s_name)
+                           && strcmp(filename, l_name)) {
+                               debug("Mismatch: |%s|%s|\n",
+                                       s_name, l_name);
+                               dentptr++;
+                               if (is_next_clust(mydata, dentptr))
+                                       break;
+                               continue;
+                       }
+
+                       memcpy(retdent, dentptr, sizeof(dir_entry));
+
+                       debug("DentName: %s", s_name);
+                       debug(", start: 0x%x", START(dentptr));
+                       debug(", size:  0x%x %s\n",
+                             FAT2CPU32(dentptr->size),
+                             (dentptr->attr & ATTR_DIR) ?
+                             "(DIR)" : "");
+
+                       return dentptr;
+               }
+
+               curclust = get_fatent_value(mydata, dir_curclust);
+               if ((curclust >= 0xffffff8) || (curclust >= 0xfff8)) {
+                       empty_dentptr = dentptr;
+                       return NULL;
+               }
+               if (CHECK_CLUST(curclust, mydata->fatsize)) {
+                       debug("curclust: 0x%x\n", curclust);
+                       debug("Invalid FAT entry\n");
+                       return NULL;
+               }
+       }
+
+       return NULL;
+}
+
+static int do_fat_write(const char *filename, void *buffer,
+       unsigned long size)
+{
+       dir_entry *dentptr, *retdent;
+       dir_slot *slotptr;
+       __u32 startsect;
+       __u32 start_cluster;
+       boot_sector bs;
+       volume_info volinfo;
+       fsdata datablock;
+       fsdata *mydata = &datablock;
+       int cursect;
+       int root_cluster, ret = -1, name_len;
+       char l_filename[VFAT_MAXLEN_BYTES];
+
+       dir_curclust = 0;
+
+       if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
+               debug("error: reading boot sector\n");
+               return -1;
+       }
+
+       total_sector = bs.total_sect;
+       if (total_sector == 0)
+               total_sector = part_size;
+
+       root_cluster = bs.root_cluster;
+
+       if (mydata->fatsize == 32)
+               mydata->fatlength = bs.fat32_length;
+       else
+               mydata->fatlength = bs.fat_length;
+
+       mydata->fat_sect = bs.reserved;
+
+       cursect = mydata->rootdir_sect
+               = mydata->fat_sect + mydata->fatlength * bs.fats;
+
+       mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0];
+       mydata->clust_size = bs.cluster_size;
+
+       if (mydata->fatsize == 32) {
+               mydata->data_begin = mydata->rootdir_sect -
+                                       (mydata->clust_size * 2);
+       } else {
+               int rootdir_size;
+
+               rootdir_size = ((bs.dir_entries[1]  * (int)256 +
+                                bs.dir_entries[0]) *
+                                sizeof(dir_entry)) /
+                                mydata->sect_size;
+               mydata->data_begin = mydata->rootdir_sect +
+                                       rootdir_size -
+                                       (mydata->clust_size * 2);
+       }
+
+       mydata->fatbufnum = -1;
+       mydata->fatbuf = malloc(FATBUFSIZE);
+       if (mydata->fatbuf == NULL) {
+               debug("Error: allocating memory\n");
+               return -1;
+       }
+
+       if (disk_read(cursect,
+               (mydata->fatsize == 32) ?
+               (mydata->clust_size) :
+               PREFETCH_BLOCKS, do_fat_read_block) < 0) {
+               debug("Error: reading rootdir block\n");
+               goto exit;
+       }
+       dentptr = (dir_entry *) do_fat_read_block;
+
+       name_len = strlen(filename);
+       memcpy(l_filename, filename, name_len);
+       downcase(l_filename);
+
+       startsect = mydata->rootdir_sect;
+       retdent = find_directory_entry(mydata, startsect,
+                               l_filename, dentptr, 0);
+       if (retdent) {
+               /* Update file size and start_cluster in a directory entry */
+               retdent->size = cpu_to_le32(size);
+               start_cluster = FAT2CPU16(retdent->start);
+               if (mydata->fatsize == 32)
+                       start_cluster |=
+                               (FAT2CPU16(retdent->starthi) << 16);
+
+               ret = check_overflow(mydata, start_cluster, size);
+               if (ret) {
+                       printf("Error: %ld overflow\n", size);
+                       goto exit;
+               }
+
+               ret = clear_fatent(mydata, start_cluster);
+               if (ret) {
+                       printf("Error: clearing FAT entries\n");
+                       goto exit;
+               }
+
+               ret = set_contents(mydata, retdent, buffer, size);
+               if (ret) {
+                       printf("Error: writing contents\n");
+                       goto exit;
+               }
+
+               /* Flush fat buffer */
+               ret = flush_fat_buffer(mydata);
+               if (ret) {
+                       printf("Error: flush fat buffer\n");
+                       goto exit;
+               }
+
+               /* Write directory table to device */
+               ret = set_cluster(mydata, dir_curclust,
+                           get_dentfromdir_block,
+                           mydata->clust_size * mydata->sect_size);
+               if (ret) {
+                       printf("Error: wrinting directory entry\n");
+                       goto exit;
+               }
+       } else {
+               slotptr = (dir_slot *)empty_dentptr;
+
+               /* Set short name to set alias checksum field in dir_slot */
+               set_name(empty_dentptr, filename);
+               fill_dir_slot(mydata, &empty_dentptr, filename);
+
+               ret = start_cluster = find_empty_cluster(mydata);
+               if (ret < 0) {
+                       printf("Error: finding empty cluster\n");
+                       goto exit;
+               }
+
+               ret = check_overflow(mydata, start_cluster, size);
+               if (ret) {
+                       printf("Error: %ld overflow\n", size);
+                       goto exit;
+               }
+
+               /* Set attribute as archieve for regular file */
+               fill_dentry(mydata, empty_dentptr, filename,
+                       start_cluster, size, 0x20);
+
+               ret = set_contents(mydata, empty_dentptr, buffer, size);
+               if (ret) {
+                       printf("Error: writing contents\n");
+                       goto exit;
+               }
+
+               /* Flush fat buffer */
+               ret = flush_fat_buffer(mydata);
+               if (ret) {
+                       printf("Error: flush fat buffer\n");
+                       goto exit;
+               }
+
+               /* Write directory table to device */
+               ret = set_cluster(mydata, dir_curclust,
+                           get_dentfromdir_block,
+                           mydata->clust_size * mydata->sect_size);
+               if (ret) {
+                       printf("Error: writing directory entry\n");
+                       goto exit;
+               }
+       }
+
+exit:
+       free(mydata->fatbuf);
+       return ret;
+}
+
+int file_fat_write(const char *filename, void *buffer, unsigned long maxsize)
+{
+       printf("writing %s\n", filename);
+       return do_fat_write(filename, buffer, maxsize);
+}
index 15dbf1094c351c41bae791951de22a9ab1a2efa7..4c92442fd34d3b9d20e5384674531c15b4b51243 100644 (file)
@@ -99,6 +99,8 @@
 #endif
 
 #define TOLOWER(c)     if((c) >= 'A' && (c) <= 'Z'){(c)+=('a' - 'A');}
+#define TOUPPER(c)     if ((c) >= 'a' && (c) <= 'z') \
+                               (c) -= ('a' - 'A');
 #define START(dent)    (FAT2CPU16((dent)->start) \
                        + (mydata->fatsize != 32 ? 0 : \
                          (FAT2CPU16((dent)->starthi) << 16)))
@@ -210,4 +212,5 @@ long file_fat_read(const char *filename, void *buffer, unsigned long maxsize);
 const char *file_getfsname(int idx);
 int fat_register_device(block_dev_desc_t *dev_desc, int part_no);
 
+int file_fat_write(const char *filename, void *buffer, unsigned long maxsize);
 #endif /* _FAT_H_ */