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-rw-r--r--src/stream/fs/fat.c516
1 files changed, 0 insertions, 516 deletions
diff --git a/src/stream/fs/fat.c b/src/stream/fs/fat.c
deleted file mode 100644
index 01e4e03cc2..0000000000
--- a/src/stream/fs/fat.c
+++ /dev/null
@@ -1,516 +0,0 @@
-/*
- * GRUB -- GRand Unified Bootloader
- * Copyright (C) 2000, 2001 Free Software Foundation, Inc.
- *
- * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#include <console/console.h>
-#include <string.h>
-#include <fs/fs.h>
-#include <fs/fat.h>
-#include <arch/byteorder.h>
-
-struct fat_superblock
-{
- int fat_offset;
- int fat_length;
- int fat_size;
- int root_offset;
- int root_max;
- int data_offset;
-
- int num_sectors;
- int num_clust;
- int clust_eof_marker;
- int sects_per_clust;
- int sectsize_bits;
- int clustsize_bits;
- int root_cluster;
-
- int cached_fat;
- int file_cluster;
- int current_cluster_num;
- int current_cluster;
-};
-
-/* pointer(s) into filesystem info buffer for DOS stuff */
-#define FAT_SUPER ( (struct fat_superblock *) \
- ( FSYS_BUF + 32256) )/* 512 bytes long */
-#define FAT_BUF ( FSYS_BUF + 30208 ) /* 4 sector FAT buffer */
-#define NAME_BUF ( FSYS_BUF + 29184 ) /* Filename buffer (833 bytes) */
-
-#define FAT_CACHE_SIZE 2048
-
-#ifdef __i386
-static __inline__ unsigned long
-log2 (unsigned long word)
-{
- __asm__ ("bsfl %1,%0"
- : "=r" (word)
- : "r" (word));
- return word;
-}
-#else /* !PPC */
-static __inline__ unsigned long
-__ilog2(unsigned long x)
-{
- unsigned long lz;
-
- asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x));
- return 31 - lz;
-}
-static __inline__ unsigned long
-log2(unsigned long x)
-{
- return __ilog2(x & -x);
-}
-#endif
-
-int
-fat_mount (void)
-{
- struct fat_bpb bpb;
- __u32 magic, first_fat;
-
- /* Check partition type for harddisk */
- if (((current_drive & 0x80) || (current_slice != 0))
- && ! IS_PC_SLICE_TYPE_FAT (current_slice)
- && (! IS_PC_SLICE_TYPE_BSD_WITH_FS (current_slice, FS_MSDOS)))
- return 0;
-
- /* Read bpb */
- if (! devread (0, 0, sizeof (bpb), (char *) &bpb))
- return 0;
-
- /* Check if the number of sectors per cluster is zero here, to avoid
- zero division. */
- if (bpb.sects_per_clust == 0)
- return 0;
-
- FAT_SUPER->sectsize_bits = log2(FAT_CVT_U16(bpb.bytes_per_sect));
- FAT_SUPER->clustsize_bits
- = FAT_SUPER->sectsize_bits + log2(bpb.sects_per_clust);
-
-printk_debug("BytsPerSec = %d\n", FAT_CVT_U16(bpb.bytes_per_sect));
-printk_debug("SecPerClus = %d\n", bpb.sects_per_clust);
-
- /* Fill in info about super block */
- FAT_SUPER->num_sectors = FAT_CVT_U16(bpb.short_sectors)
- ? FAT_CVT_U16(bpb.short_sectors) : FAT_CVT_U32(bpb.long_sectors);
-
-printk_debug("TotSec16 = %d\n", FAT_CVT_U16(bpb.short_sectors));
-printk_debug("TotSec32 = %d\n", FAT_CVT_U32(bpb.long_sectors));
-
- /* FAT offset and length */
- FAT_SUPER->fat_offset = FAT_CVT_U16(bpb.reserved_sects);
- FAT_SUPER->fat_length = FAT_CVT_U16(bpb.fat_length)
- ? FAT_CVT_U16(bpb.fat_length) : FAT_CVT_U32(bpb.fat32_length);
-
-printk_debug("RsvdSecCnt = %d\n", FAT_CVT_U16(bpb.reserved_sects));
-printk_debug("FATSx16 = %d\n", FAT_CVT_U16(bpb.fat_length));
-printk_debug("FATSx32 = %d\n", FAT_CVT_U32(bpb.fat32_length));
-
- /* Rootdir offset and length for FAT12/16 */
- FAT_SUPER->root_offset =
- FAT_SUPER->fat_offset + bpb.num_fats * FAT_SUPER->fat_length;
- FAT_SUPER->root_max = FAT_DIRENTRY_LENGTH * FAT_CVT_U16(bpb.dir_entries);
-
-printk_debug("RootEntCnt = %d\n", FAT_CVT_U16(bpb.dir_entries));
-
- /* Data offset and number of clusters */
- FAT_SUPER->data_offset =
- FAT_SUPER->root_offset
- + ((FAT_SUPER->root_max - 1) >> FAT_SUPER->sectsize_bits) + 1;
- FAT_SUPER->num_clust =
- 2 + ((FAT_SUPER->num_sectors - FAT_SUPER->data_offset)
- / bpb.sects_per_clust);
- FAT_SUPER->sects_per_clust = bpb.sects_per_clust;
-
- if (!bpb.fat_length)
- {
- /* This is a FAT32 */
- if (FAT_CVT_U16(bpb.dir_entries))
- return 0;
-
-printk_debug("We seem to be FAT32\n");
-printk_debug("ExtFlags = 0x%x\n", FAT_CVT_U16(bpb.flags));
-printk_debug("RootClus = %d\n", FAT_CVT_U32(bpb.root_cluster));
- if (FAT_CVT_U16(bpb.flags) & 0x0080)
- {
- /* FAT mirroring is disabled, get active FAT */
- int active_fat = FAT_CVT_U16(bpb.flags) & 0x000f;
- if (active_fat >= bpb.num_fats)
- return 0;
- FAT_SUPER->fat_offset += active_fat * FAT_SUPER->fat_length;
- }
-
- FAT_SUPER->fat_size = 8;
- FAT_SUPER->root_cluster = FAT_CVT_U32(bpb.root_cluster);
-
- /* Yes the following is correct. FAT32 should be called FAT28 :) */
- FAT_SUPER->clust_eof_marker = 0xffffff8;
- }
- else
- {
- if (!FAT_SUPER->root_max)
- return 0;
-
-printk_debug("We seem to be FAT12/16\n");
- FAT_SUPER->root_cluster = -1;
- if (FAT_SUPER->num_clust > FAT_MAX_12BIT_CLUST)
- {
- FAT_SUPER->fat_size = 4;
- FAT_SUPER->clust_eof_marker = 0xfff8;
- }
- else
- {
- FAT_SUPER->fat_size = 3;
- FAT_SUPER->clust_eof_marker = 0xff8;
- }
- }
-
- /* Now do some sanity checks */
-
- if (FAT_CVT_U16(bpb.bytes_per_sect) != (1 << FAT_SUPER->sectsize_bits)
- || FAT_CVT_U16(bpb.bytes_per_sect) != SECTOR_SIZE
- || bpb.sects_per_clust != (1 << (FAT_SUPER->clustsize_bits
- - FAT_SUPER->sectsize_bits))
- || FAT_SUPER->num_clust <= 2
- || (FAT_SUPER->fat_size * FAT_SUPER->num_clust / (2 * SECTOR_SIZE)
- > FAT_SUPER->fat_length))
- return 0;
-
- /* kbs: Media check on first FAT entry [ported from PUPA] */
-
- if (!devread(FAT_SUPER->fat_offset, 0,
- sizeof(first_fat), (char *)&first_fat))
- return 0;
-
-printk_debug("Media = 0x%x\n", bpb.media);
-
- if (FAT_SUPER->fat_size == 8)
- {
- first_fat = le32_to_cpu(first_fat) & 0x0fffffff;
- magic = 0x0fffff00;
- }
- else if (FAT_SUPER->fat_size == 4)
- {
- first_fat = le32_to_cpu(first_fat) & 0x0000ffff;
- magic = 0xff00;
- }
- else
- {
- first_fat = le32_to_cpu(first_fat) & 0x00000fff;
- magic = 0x0f00;
- }
-
- if (first_fat != (magic | bpb.media))
- return 0;
-
- FAT_SUPER->cached_fat = - 2 * FAT_CACHE_SIZE;
- return 1;
-}
-
-int
-fat_read (char *buf, int len)
-{
- int logical_clust;
- int offset;
- int ret = 0;
- int size;
-
- if (FAT_SUPER->file_cluster < 0)
- {
- /* root directory for fat16 */
- size = FAT_SUPER->root_max - filepos;
- if (size > len)
- size = len;
- if (!devread(FAT_SUPER->root_offset, filepos, size, buf))
- return 0;
- filepos += size;
- return size;
- }
-
- logical_clust = filepos >> FAT_SUPER->clustsize_bits;
- offset = (filepos & ((1 << FAT_SUPER->clustsize_bits) - 1));
- if (logical_clust < FAT_SUPER->current_cluster_num)
- {
- FAT_SUPER->current_cluster_num = 0;
- FAT_SUPER->current_cluster = FAT_SUPER->file_cluster;
- }
-
- while (len > 0)
- {
- int sector;
- while (logical_clust > FAT_SUPER->current_cluster_num)
- {
- /* calculate next cluster */
- int fat_entry =
- FAT_SUPER->current_cluster * FAT_SUPER->fat_size;
- int next_cluster;
- int cached_pos = (fat_entry - FAT_SUPER->cached_fat);
-
- if (cached_pos < 0 ||
- (cached_pos + FAT_SUPER->fat_size) > 2*FAT_CACHE_SIZE)
- {
- FAT_SUPER->cached_fat = (fat_entry & ~(2*SECTOR_SIZE - 1));
- cached_pos = (fat_entry - FAT_SUPER->cached_fat);
- sector = FAT_SUPER->fat_offset
- + FAT_SUPER->cached_fat / (2*SECTOR_SIZE);
- if (!devread (sector, 0, FAT_CACHE_SIZE, (char*) FAT_BUF))
- return 0;
- }
- next_cluster = FAT_CVT_U32(FAT_BUF + (cached_pos >> 1));
- if (FAT_SUPER->fat_size == 3)
- {
- if (cached_pos & 1)
- next_cluster >>= 4;
- next_cluster &= 0xFFF;
- }
- else if (FAT_SUPER->fat_size == 4)
- next_cluster &= 0xFFFF;
-
- if (next_cluster >= FAT_SUPER->clust_eof_marker)
- return ret;
- if (next_cluster < 2 || next_cluster >= FAT_SUPER->num_clust)
- {
- errnum = ERR_FSYS_CORRUPT;
- return 0;
- }
-
- FAT_SUPER->current_cluster = next_cluster;
- FAT_SUPER->current_cluster_num++;
- }
-
- sector = FAT_SUPER->data_offset +
- ((FAT_SUPER->current_cluster - 2) << (FAT_SUPER->clustsize_bits
- - FAT_SUPER->sectsize_bits));
- size = (1 << FAT_SUPER->clustsize_bits) - offset;
- if (size > len)
- size = len;
-
- disk_read_func = disk_read_hook;
-
- devread(sector, offset, size, buf);
-
- disk_read_func = 0;
-
- len -= size;
- buf += size;
- ret += size;
- filepos += size;
- logical_clust++;
- offset = 0;
- }
- return errnum ? 0 : ret;
-}
-
-int
-fat_dir (char *dirname)
-{
- char *rest, ch, dir_buf[FAT_DIRENTRY_LENGTH];
- char *filename = (char *) NAME_BUF;
- int attrib = FAT_ATTRIB_DIR;
-#ifndef STAGE1_5
- int do_possibilities = 0;
-#endif
-
- /* XXX I18N:
- * the positions 2,4,6 etc are high bytes of a 16 bit unicode char
- */
- static unsigned char longdir_pos[] =
- { 1, 3, 5, 7, 9, 14, 16, 18, 20, 22, 24, 28, 30 };
- int slot = -2;
- int alias_checksum = -1;
-
- FAT_SUPER->file_cluster = FAT_SUPER->root_cluster;
- filepos = 0;
- FAT_SUPER->current_cluster_num = MAXINT;
-
- /* main loop to find desired directory entry */
- loop:
-
- /* if we have a real file (and we're not just printing possibilities),
- then this is where we want to exit */
-
- if (!*dirname || isspace (*dirname))
- {
- if (attrib & FAT_ATTRIB_DIR)
- {
- errnum = ERR_BAD_FILETYPE;
- return 0;
- }
-
- return 1;
- }
-
- /* continue with the file/directory name interpretation */
-
- while (*dirname == '/')
- dirname++;
-
- if (!(attrib & FAT_ATTRIB_DIR))
- {
- errnum = ERR_BAD_FILETYPE;
- return 0;
- }
- /* Directories don't have a file size */
- filemax = MAXINT;
-
- for (rest = dirname; (ch = *rest) && !isspace (ch) && ch != '/'; rest++);
-
- *rest = 0;
-
-# ifndef STAGE1_5
- if (print_possibilities && ch != '/')
- do_possibilities = 1;
-# endif
-
- while (1)
- {
- if (fat_read (dir_buf, FAT_DIRENTRY_LENGTH) != FAT_DIRENTRY_LENGTH
- || dir_buf[0] == 0)
- {
- if (!errnum)
- {
-# ifndef STAGE1_5
- if (print_possibilities < 0)
- {
-#if 0
- putchar ('\n');
-#endif
- return 1;
- }
-# endif /* STAGE1_5 */
-
- errnum = ERR_FILE_NOT_FOUND;
- *rest = ch;
- }
-
- return 0;
- }
-
- if (FAT_DIRENTRY_ATTRIB (dir_buf) == FAT_ATTRIB_LONGNAME)
- {
- /* This is a long filename. The filename is build from back
- * to front and may span multiple entries. To bind these
- * entries together they all contain the same checksum over
- * the short alias.
- *
- * The id field tells if this is the first entry (the last
- * part) of the long filename, and also at which offset this
- * belongs.
- *
- * We just write the part of the long filename this entry
- * describes and continue with the next dir entry.
- */
- int i, offset;
- unsigned char id = FAT_LONGDIR_ID(dir_buf);
-
- if ((id & 0x40))
- {
- id &= 0x3f;
- slot = id;
- filename[slot * 13] = 0;
- alias_checksum = FAT_LONGDIR_ALIASCHECKSUM(dir_buf);
- }
-
- if (id != slot || slot == 0
- || alias_checksum != FAT_LONGDIR_ALIASCHECKSUM(dir_buf))
- {
- alias_checksum = -1;
- continue;
- }
-
- slot--;
- offset = slot * 13;
-
- for (i=0; i < 13; i++)
- filename[offset+i] = dir_buf[longdir_pos[i]];
- continue;
- }
-
- if (!FAT_DIRENTRY_VALID (dir_buf))
- continue;
-
- if (alias_checksum != -1 && slot == 0)
- {
- int i;
- unsigned char sum;
-
- slot = -2;
- for (sum = 0, i = 0; i< 11; i++)
- sum = ((sum >> 1) | (sum << 7)) + dir_buf[i];
-
- if (sum == alias_checksum)
- {
-# ifndef STAGE1_5
- if (do_possibilities)
- goto print_filename;
-# endif /* STAGE1_5 */
-
- if (substring (dirname, filename) == 0)
- break;
- }
- }
-
- /* XXX convert to 8.3 filename format here */
- {
- int i, j, c;
-
- for (i = 0; i < 8 && (c = filename[i] = tolower (dir_buf[i]))
- && !isspace (c); i++);
-
- filename[i++] = '.';
-
- for (j = 0; j < 3 && (c = filename[i + j] = tolower (dir_buf[8 + j]))
- && !isspace (c); j++);
-
- if (j == 0)
- i--;
-
- filename[i + j] = 0;
- }
-
-# ifndef STAGE1_5
- if (do_possibilities)
- {
- print_filename:
- if (substring (dirname, filename) <= 0)
- {
- if (print_possibilities > 0)
- print_possibilities = -print_possibilities;
- print_a_completion (filename);
- }
- continue;
- }
-# endif /* STAGE1_5 */
-
- if (substring (dirname, filename) == 0)
- break;
- }
-
- *(dirname = rest) = ch;
-
- attrib = FAT_DIRENTRY_ATTRIB (dir_buf);
- filemax = FAT_DIRENTRY_FILELENGTH (dir_buf);
- filepos = 0;
- FAT_SUPER->file_cluster = FAT_DIRENTRY_FIRST_CLUSTER (dir_buf);
- FAT_SUPER->current_cluster_num = MAXINT;
-
- /* go back to main loop at top of function */
- goto loop;
-}
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