📄 ff.c
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)
{
clust -= 2;
if (clust >= (fs->max_clust - 2)) return 0; /* Invalid cluster# */
return clust * fs->csize + fs->database;
}
/*-----------------------------------------------------------------------*/
/* Move directory pointer to next */
/*-----------------------------------------------------------------------*/
static
BOOL next_dir_entry ( /* TRUE: successful, FALSE: could not move next */
DIR *dj /* Pointer to directory object */
)
{
DWORD clust;
WORD idx;
idx = dj->index + 1;
if ((idx & ((SS(dj->fs) - 1) / 32)) == 0) { /* Table sector changed? */
dj->sect++; /* Next sector */
if (dj->clust == 0) { /* In static table */
if (idx >= dj->fs->n_rootdir) return FALSE; /* Reached to end of table */
} else { /* In dynamic table */
if (((idx / (SS(dj->fs) / 32)) & (dj->fs->csize - 1)) == 0) { /* Cluster changed? */
clust = get_cluster(dj->fs, dj->clust); /* Get next cluster */
if (clust < 2 || clust >= dj->fs->max_clust) /* Reached to end of table */
return FALSE;
dj->clust = clust; /* Initialize for new cluster */
dj->sect = clust2sect(dj->fs, clust);
}
}
}
dj->index = idx; /* Lower several bits of dj->index indicates offset in dj->sect */
return TRUE;
}
/*-----------------------------------------------------------------------*/
/* Get file status from directory entry */
/*-----------------------------------------------------------------------*/
#if _FS_MINIMIZE <= 1
static
void get_fileinfo ( /* No return code */
FILINFO *finfo, /* Ptr to store the file information */
const BYTE *dir /* Ptr to the directory entry */
)
{
BYTE n, c, a;
char *p;
p = &finfo->fname[0];
a = _USE_NTFLAG ? dir[DIR_NTres] : 0; /* NT flag */
for (n = 0; n < 8; n++) { /* Convert file name (body) */
c = dir[n];
if (c == ' ') break;
if (c == 0x05) c = 0xE5;
if (a & 0x08 && c >= 'A' && c <= 'Z') c += 0x20;
*p++ = c;
}
if (dir[8] != ' ') { /* Convert file name (extension) */
*p++ = '.';
for (n = 8; n < 11; n++) {
c = dir[n];
if (c == ' ') break;
if (a & 0x10 && c >= 'A' && c <= 'Z') c += 0x20;
*p++ = c;
}
}
*p = '\0';
finfo->fattrib = dir[DIR_Attr]; /* Attribute */
finfo->fsize = LD_DWORD(&dir[DIR_FileSize]); /* Size */
finfo->fdate = LD_WORD(&dir[DIR_WrtDate]); /* Date */
finfo->ftime = LD_WORD(&dir[DIR_WrtTime]); /* Time */
}
#endif /* _FS_MINIMIZE <= 1 */
/*-----------------------------------------------------------------------*/
/* Pick a paragraph and create the name in format of directory entry */
/*-----------------------------------------------------------------------*/
static
char make_dirfile ( /* 1: error - detected an invalid format, '\0'or'/': next character */
const char **path, /* Pointer to the file path pointer */
char *dirname /* Pointer to directory name buffer {Name(8), Ext(3), NT flag(1)} */
)
{
BYTE n, t, c, a, b;
memset(dirname, ' ', 8+3); /* Fill buffer with spaces */
a = 0; b = 0x18; /* NT flag */
n = 0; t = 8;
for (;;) {
c = *(*path)++;
if (c == '\0' || c == '/') { /* Reached to end of str or directory separator */
if (n == 0) break;
dirname[11] = _USE_NTFLAG ? (a & b) : 0;
return c;
}
if (c <= ' ' || c == 0x7F) break; /* Reject invisible chars */
if (c == '.') {
if (!(a & 1) && n >= 1 && n <= 8) { /* Enter extension part */
n = 8; t = 11; continue;
}
break;
}
if (_USE_SJIS &&
((c >= 0x81 && c <= 0x9F) || /* Accept S-JIS code */
(c >= 0xE0 && c <= 0xFC))) {
if (n == 0 && c == 0xE5) /* Change heading \xE5 to \x05 */
c = 0x05;
a ^= 0x01; goto md_l2;
}
if (c == '"') break; /* Reject " */
if (c <= ')') goto md_l1; /* Accept ! # $ % & ' ( ) */
if (c <= ',') break; /* Reject * + , */
if (c <= '9') goto md_l1; /* Accept - 0-9 */
if (c <= '?') break; /* Reject : ; < = > ? */
if (!(a & 1)) { /* These checks are not applied to S-JIS 2nd byte */
if (c == '|') break; /* Reject | */
if (c >= '[' && c <= ']') break;/* Reject [ \ ] */
if (_USE_NTFLAG && c >= 'A' && c <= 'Z')
(t == 8) ? (b &= 0xF7) : (b &= 0xEF);
if (c >= 'a' && c <= 'z') { /* Convert to upper case */
c -= 0x20;
if (_USE_NTFLAG) (t == 8) ? (a |= 0x08) : (a |= 0x10);
}
}
md_l1:
a &= 0xFE;
md_l2:
if (n >= t) break;
dirname[n++] = c;
}
return 1;
}
/*-----------------------------------------------------------------------*/
/* Trace a file path */
/*-----------------------------------------------------------------------*/
static
FRESULT trace_path ( /* FR_OK(0): successful, !=0: error code */
DIR *dj, /* Pointer to directory object to return last directory */
char *fn, /* Pointer to last segment name to return {file(8),ext(3),attr(1)} */
const char *path, /* Full-path string to trace a file or directory */
BYTE **dir /* Pointer to pointer to found entry to retutn */
)
{
DWORD clust;
char ds;
BYTE *dptr = NULL;
FATFS *fs = dj->fs;
/* Initialize directory object */
clust = fs->dirbase;
if (fs->fs_type == FS_FAT32) {
dj->clust = dj->sclust = clust;
dj->sect = clust2sect(fs, clust);
} else {
dj->clust = dj->sclust = 0;
dj->sect = clust;
}
dj->index = 0;
if (*path == '\0') { /* Null path means the root directory */
*dir = NULL; return FR_OK;
}
for (;;) {
ds = make_dirfile(&path, fn); /* Get a paragraph into fn[] */
if (ds == 1) return FR_INVALID_NAME;
for (;;) {
if (!move_window(fs, dj->sect)) return FR_RW_ERROR;
dptr = &fs->win[(dj->index & ((SS(fs) - 1) / 32)) * 32]; /* Pointer to the directory entry */
if (dptr[DIR_Name] == 0) /* Has it reached to end of dir? */
return !ds ? FR_NO_FILE : FR_NO_PATH;
if (dptr[DIR_Name] != 0xE5 /* Matched? */
&& !(dptr[DIR_Attr] & AM_VOL)
&& !memcmp(&dptr[DIR_Name], fn, 8+3) ) break;
if (!next_dir_entry(dj)) /* Next directory pointer */
return !ds ? FR_NO_FILE : FR_NO_PATH;
}
if (!ds) { *dir = dptr; return FR_OK; } /* Matched with end of path */
if (!(dptr[DIR_Attr] & AM_DIR)) return FR_NO_PATH; /* Cannot trace because it is a file */
clust = ((DWORD)LD_WORD(&dptr[DIR_FstClusHI]) << 16) | LD_WORD(&dptr[DIR_FstClusLO]); /* Get cluster# of the directory */
dj->clust = dj->sclust = clust; /* Restart scanning at the new directory */
dj->sect = clust2sect(fs, clust);
dj->index = 2;
}
}
/*-----------------------------------------------------------------------*/
/* Reserve a directory entry */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY
static
FRESULT reserve_direntry ( /* FR_OK: successful, FR_DENIED: no free entry, FR_RW_ERROR: a disk error occured */
DIR *dj, /* Target directory to create new entry */
BYTE **dir /* Pointer to pointer to created entry to retutn */
)
{
DWORD clust, sector;
BYTE c, n, *dptr;
FATFS *fs = dj->fs;
/* Re-initialize directory object */
clust = dj->sclust;
if (clust != 0) { /* Dyanmic directory table */
dj->clust = clust;
dj->sect = clust2sect(fs, clust);
} else { /* Static directory table */
dj->sect = fs->dirbase;
}
dj->index = 0;
do {
if (!move_window(fs, dj->sect)) return FR_RW_ERROR;
dptr = &fs->win[(dj->index & ((SS(dj->fs) - 1) / 32)) * 32]; /* Pointer to the directory entry */
c = dptr[DIR_Name];
if (c == 0 || c == 0xE5) { /* Found an empty entry */
*dir = dptr; return FR_OK;
}
} while (next_dir_entry(dj)); /* Next directory pointer */
/* Reached to end of the directory table */
/* Abort when it is a static table or could not stretch dynamic table */
if (clust == 0 || !(clust = create_chain(fs, dj->clust))) return FR_DENIED;
if (clust == 1 || !move_window(fs, 0)) return FR_RW_ERROR;
/* Cleanup the expanded table */
fs->winsect = sector = clust2sect(fs, clust);
memset(fs->win, 0, SS(fs));
for (n = fs->csize; n; n--) {
if (disk_write(fs->drive, fs->win, sector, 1) != RES_OK)
return FR_RW_ERROR;
sector++;
}
fs->winflag = 1;
*dir = fs->win;
return FR_OK;
}
#endif /* !_FS_READONLY */
/*-----------------------------------------------------------------------*/
/* Load boot record and check if it is an FAT boot record */
/*-----------------------------------------------------------------------*/
static
BYTE check_fs ( /* 0:The FAT boot record, 1:Valid boot record but not an FAT, 2:Not a boot record or error */
FATFS *fs, /* File system object */
DWORD sect /* Sector# (lba) to check if it is an FAT boot record or not */
)
{
if (disk_read(fs->drive, fs->win, sect, 1) != RES_OK) /* Load boot record */
return 2;
if (LD_WORD(&fs->win[BS_55AA]) != 0xAA55) /* Check record signature (always placed at offset 510 even if the sector size is >512) */
return 2;
if (!memcmp(&fs->win[BS_FilSysType], "FAT", 3)) /* Check FAT signature */
return 0;
if (!memcmp(&fs->win[BS_FilSysType32], "FAT32", 5) && !(fs->win[BPB_ExtFlags] & 0x80))
return 0;
return 1;
}
/*-----------------------------------------------------------------------*/
/* Make sure that the file system is valid */
/*-----------------------------------------------------------------------*/
static
FRESULT auto_mount ( /* FR_OK(0): successful, !=0: any error occured */
const char **path, /* Pointer to pointer to the path name (drive number) */
FATFS **rfs, /* Pointer to pointer to the found file system object */
BYTE chk_wp /* !=0: Check media write protection for write access */
)
{
BYTE drv, fmt, *tbl;
DSTATUS stat;
DWORD bootsect, fatsize, totalsect, maxclust;
const char *p = *path;
FATFS *fs;
/* Get drive number from the path name */
while (*p == ' ') p++; /* Strip leading spaces */
drv = p[0] - '0'; /* Is there a drive number? */
if (drv <= 9 && p[1] == ':')
p += 2; /* Found a drive number, get and strip it */
else
drv = 0; /* No drive number is given, use drive number 0 as default */
if (*p == '/') p++; /* Strip heading slash */
*path = p; /* Return pointer to the path name */
/* Check if the drive number is valid or not */
if (drv >= _DRIVES) return FR_INVALID_DRIVE; /* Is the drive number valid? */
*rfs = fs = FatFs[drv]; /* Returen pointer to the corresponding file system object */
if (!fs) return FR_NOT_ENABLED; /* Is the file system object registered? */
if (fs->fs_type) { /* If the logical drive has been mounted */
stat = disk_status(fs->drive);
if (!(stat & STA_NOINIT)) { /* and physical drive is kept initialized (has not been changed), */
#if !_FS_READONLY
if (chk_wp && (stat & STA_PROTECT)) /* Check write protection if needed */
return FR_WRITE_PROTECTED;
#endif
return FR_OK; /* The file system object is valid */
}
}
/* The logical drive must be re-mounted. Following code attempts to mount the logical drive */
memset(fs, 0, sizeof(FATFS)); /* Clean-up the file system object */
fs->drive = LD2PD(drv); /* Bind the logical drive and a physical drive */
stat = disk_initialize(fs->drive); /* Initialize low level disk I/O layer */
if (stat & STA_NOINIT) /* Check if the drive is ready */
return FR_NOT_READY;
#if S_MAX_SIZ > 512 /* Get disk sector size if needed */
if (disk_ioctl(drv, GET_SECTOR_SIZE, &SS(fs)) != RES_OK || SS(fs) > S_MAX_SIZ)
return FR_NO_FILESYSTEM;
#endif
#if !_FS_READONLY
if (chk_wp && (stat & STA_PROTECT)) /* Check write protection if needed */
return FR_WRITE_PROTECTED;
#endif
/* Search FAT partition on the drive */
fmt = check_fs(fs, bootsect = 0); /* Check sector 0 as an SFD format */
if (fmt == 1) { /* Not an FAT boot record, it may be patitioned */
/* Check a partition listed in top of the partition table */
tbl = &fs->win[MBR_Table + LD2PT(drv) * 16]; /* Partition table */
if (tbl[4]) { /* Is the partition existing? */
bootsect = LD_DWORD(&tbl[8]); /* Partition offset in LBA */
fmt = check_fs(fs, bootsect); /* Check the partition */
}
}
if (fmt || LD_WORD(&fs->win[BPB_BytsPerSec]) != SS(fs)) /* No valid FAT patition is found */
return FR_NO_FILESYSTEM;
/* Initialize the file system object */
fatsize = LD_WORD(&fs->win[BPB_FATSz16]); /* Number of sectors per FAT */
if (!fatsize) fatsize = LD_DWORD(&fs->win[BPB_FATSz32]);
fs->sects_fat = fatsize;
fs->n_fats = fs->win[BPB_NumFATs]; /* Number of FAT copies */
fatsize *= fs->n_fats; /* (Number of sectors in FAT area) */
fs->fatbase = bootsect + LD_WORD(&fs->win[BPB_RsvdSecCnt]); /* FAT start sector (lba) */
fs->csize = fs->win[BPB_SecPerClus]; /* Number of sectors per cluster */
fs->n_rootdir = LD_WORD(&fs->win[BPB_RootEntCnt]); /* Nmuber of root directory entries */
totalsect = LD_WORD(&fs->win[BPB_TotSec16]); /* Number of sectors on the file system */
if (!totalsect) totalsect = LD_DWORD(&fs->win[BPB_TotSec32]);
fs->max_clust = maxclust = (totalsect /* max_clust = Last cluster# + 1 */
- LD_WORD(&fs->win[BPB_RsvdSecCnt]) - fatsize - fs->n_rootdir / (SS(fs)/32)
) / fs->csize + 2;
fmt = FS_FAT12; /* Determine the FAT sub type */
if (maxclust >= 0xFF7) fmt = FS_FAT16;
if (maxclust >= 0xFFF7) fmt = FS_FAT32;
if (fmt == FS_FAT32)
fs->dirbase = LD_DWORD(&fs->win[BPB_RootClus]); /* Root directory start cluster */
else
fs->dirbase = fs->fatbase + fatsize; /* Root directory start sector (lba) */
fs->database = fs->fatbase + fatsize + fs->n_rootdir / (SS(fs)/32); /* Data start sector (lba) */
#if !_FS_READONLY
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