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applied http://sourceforge.net/support/tracker.php?aid=2885644

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This commit is contained in:
Dave Murphy 2009-10-27 00:55:26 +00:00
parent 7f77159f6a
commit 79e3dc0948
2 changed files with 86 additions and 77 deletions
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2
Makefile
View File

@ -6,7 +6,7 @@ export TOPDIR := $(CURDIR)
export LIBFAT_MAJOR := 1
export LIBFAT_MINOR := 0
export LIBFAT_PATCH := 5
export LIBFAT_PATCH := 6
export VERSTRING := $(LIBFAT_MAJOR).$(LIBFAT_MINOR).$(LIBFAT_PATCH)

161
source/fatfile.c
View File

@ -26,6 +26,8 @@
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
2009-10-23 oggzee: fixes for cluster aligned file size (write, truncate, seek)
*/
@ -509,6 +511,43 @@ ssize_t _FAT_read_r (struct _reent *r, int fd, char *ptr, size_t len) {
return len;
}
// if current position is on the cluster border and more data has to be written
// then get next cluster or allocate next cluster
// this solves the over-allocation problems when file size is aligned to cluster size
// return true on succes, false on error
static bool _FAT_check_position_for_next_cluster(struct _reent *r,
FILE_POSITION *position, PARTITION* partition, size_t remain, bool *flagNoError)
{
uint32_t tempNextCluster;
// do nothing if no more data to write
if (remain == 0) return true;
if (flagNoError && *flagNoError == false) return false;
if ((remain < 0) || (position->sector > partition->sectorsPerCluster)) {
// invalid arguments - internal error
r->_errno = EINVAL;
goto err;
}
if (position->sector == partition->sectorsPerCluster) {
// need to advance to next cluster
tempNextCluster = _FAT_fat_nextCluster(partition, position->cluster);
if ((tempNextCluster == CLUSTER_EOF) || (tempNextCluster == CLUSTER_FREE)) {
// Ran out of clusters so get a new one
tempNextCluster = _FAT_fat_linkFreeCluster(partition, position->cluster);
}
if (!_FAT_fat_isValidCluster(partition, tempNextCluster)) {
// Couldn't get a cluster, so abort
r->_errno = ENOSPC;
goto err;
}
position->sector = 0;
position->cluster = tempNextCluster;
}
return true;
err:
if (flagNoError) *flagNoError = false;
return false;
}
/*
Extend a file so that the size is the same as the rwPosition
*/
@ -576,19 +615,9 @@ static bool _FAT_file_extend_r (struct _reent *r, FILE_STRUCT* file) {
position.sector ++;
}
if (position.sector >= partition->sectorsPerCluster) {
position.sector = 0;
tempNextCluster = _FAT_fat_nextCluster(partition, position.cluster);
if ((tempNextCluster == CLUSTER_EOF) || (tempNextCluster == CLUSTER_FREE)) {
// Ran out of clusters so get a new one
tempNextCluster = _FAT_fat_linkFreeCluster(partition, position.cluster);
}
if (!_FAT_fat_isValidCluster(partition, tempNextCluster)) {
// Couldn't get a cluster, so abort
r->_errno = ENOSPC;
return false;
}
position.cluster = tempNextCluster;
if (!_FAT_check_position_for_next_cluster(r, &position, partition, remain, NULL)) {
// error already marked
return false;
}
if (remain > 0) {
@ -603,7 +632,6 @@ static bool _FAT_file_extend_r (struct _reent *r, FILE_STRUCT* file) {
return true;
}
ssize_t _FAT_write_r (struct _reent *r, int fd, const char *ptr, size_t len) {
FILE_STRUCT* file = (FILE_STRUCT*) fd;
PARTITION* partition;
@ -680,21 +708,7 @@ ssize_t _FAT_write_r (struct _reent *r, int fd, const char *ptr, size_t len) {
}
// Move onto next cluster if needed
if (position.sector >= partition->sectorsPerCluster) {
position.sector = 0;
tempNextCluster = _FAT_fat_nextCluster(partition, position.cluster);
if ((tempNextCluster == CLUSTER_EOF) || (tempNextCluster == CLUSTER_FREE)) {
// Ran out of clusters so get a new one
tempNextCluster = _FAT_fat_linkFreeCluster(partition, position.cluster);
}
if (!_FAT_fat_isValidCluster(partition, tempNextCluster)) {
// Couldn't get a cluster, so abort
r->_errno = ENOSPC;
flagNoError = false;
} else {
position.cluster = tempNextCluster;
}
}
_FAT_check_position_for_next_cluster(r, &position, partition, remain, &flagNoError);
// Align to sector
tempVar = BYTES_PER_READ - position.byte;
@ -740,49 +754,35 @@ ssize_t _FAT_write_r (struct _reent *r, int fd, const char *ptr, size_t len) {
}
}
if ((position.sector >= partition->sectorsPerCluster) && flagNoError && (remain > 0)) {
position.sector = 0;
tempNextCluster = _FAT_fat_nextCluster(partition, position.cluster);
if ((tempNextCluster == CLUSTER_EOF) || (tempNextCluster == CLUSTER_FREE)) {
// Ran out of clusters so get a new one
tempNextCluster = _FAT_fat_linkFreeCluster(partition, position.cluster);
}
if (!_FAT_fat_isValidCluster(partition, tempNextCluster)) {
// Couldn't get a cluster, so abort
r->_errno = ENOSPC;
flagNoError = false;
} else {
position.cluster = tempNextCluster;
}
}
size_t chunkSize = partition->bytesPerCluster;
// Write whole clusters
while ((remain >= partition->bytesPerCluster) && flagNoError) {
uint32_t chunkEnd;
// allocate next cluster
_FAT_check_position_for_next_cluster(r, &position, partition, remain, &flagNoError);
if (!flagNoError) break;
// set indexes to the current position
uint32_t chunkEnd = position.cluster;
uint32_t nextChunkStart = position.cluster;
size_t chunkSize = partition->bytesPerCluster;
FILE_POSITION next_position = position;
do {
chunkEnd = nextChunkStart;
nextChunkStart = _FAT_fat_nextCluster (partition, chunkEnd);
if ((nextChunkStart == CLUSTER_EOF) || (nextChunkStart == CLUSTER_FREE)) {
// Ran out of clusters so get a new one
nextChunkStart = _FAT_fat_linkFreeCluster(partition, chunkEnd);
}
if (!_FAT_fat_isValidCluster(partition, nextChunkStart)) {
// Couldn't get a cluster, so abort
r->_errno = ENOSPC;
flagNoError = false;
} else {
chunkSize += partition->bytesPerCluster;
}
} while (flagNoError && (nextChunkStart == chunkEnd + 1) &&
// group consecutive clusters
while (flagNoError &&
#ifdef LIMIT_SECTORS
(chunkSize + partition->bytesPerCluster <= LIMIT_SECTORS * BYTES_PER_READ) &&
(chunkSize + partition->bytesPerCluster <= LIMIT_SECTORS * BYTES_PER_READ) &&
#endif
(chunkSize + partition->bytesPerCluster <= remain));
(chunkSize + partition->bytesPerCluster < remain))
{
// pretend to use up all sectors in next_position
next_position.sector = partition->sectorsPerCluster;
// get or allocate next cluster
_FAT_check_position_for_next_cluster(r, &next_position, partition,
remain - chunkSize, &flagNoError);
if (!flagNoError) break; // exit loop on error
nextChunkStart = next_position.cluster;
if (nextChunkStart != chunkEnd + 1) break; // exit loop if not consecutive
chunkEnd = nextChunkStart;
chunkSize += partition->bytesPerCluster;
}
if ( !_FAT_cache_writeSectors (cache,
_FAT_fat_clusterToSector(partition, position.cluster), chunkSize / BYTES_PER_READ, ptr))
@ -794,8 +794,10 @@ ssize_t _FAT_write_r (struct _reent *r, int fd, const char *ptr, size_t len) {
ptr += chunkSize;
remain -= chunkSize;
if (_FAT_fat_isValidCluster(partition, nextChunkStart)) {
if ((chunkEnd != nextChunkStart) && _FAT_fat_isValidCluster(partition, nextChunkStart)) {
// new cluster is already allocated (because it was not consecutive)
position.cluster = nextChunkStart;
position.sector = 0;
} else {
// Allocate a new cluster when next writing the file
position.cluster = chunkEnd;
@ -803,6 +805,9 @@ ssize_t _FAT_write_r (struct _reent *r, int fd, const char *ptr, size_t len) {
}
}
// allocate next cluster if needed
_FAT_check_position_for_next_cluster(r, &position, partition, remain, &flagNoError);
// Write remaining sectors
tempVar = remain / BYTES_PER_READ; // Number of sectors left
if ((tempVar > 0) && flagNoError) {
@ -906,20 +911,24 @@ off_t _FAT_seek_r (struct _reent *r, int fd, off_t pos, int dir) {
// Only change the read/write position if it is within the bounds of the current filesize,
// or at the very edge of the file
if (position <= file->filesize && file->startCluster != CLUSTER_FREE) {
// Calculate where the correct cluster is
// how many clusters from start of file
clusCount = position / partition->bytesPerCluster;
cluster = file->startCluster;
if (position >= file->currentPosition) {
// start from current cluster
int currentCount = file->currentPosition / partition->bytesPerCluster;
if (file->rwPosition.sector == partition->sectorsPerCluster) {
currentCount--;
}
clusCount -= currentCount;
cluster = file->rwPosition.cluster;
}
// Calculate the sector and byte of the current position,
// and store them
file->rwPosition.sector = (position % partition->bytesPerCluster) / BYTES_PER_READ;
file->rwPosition.byte = position % BYTES_PER_READ;
// Calculate where the correct cluster is
if ((position >= file->currentPosition) && (file->rwPosition.sector != partition->sectorsPerCluster)) {
clusCount = (position / partition->bytesPerCluster) - (file->currentPosition / partition->bytesPerCluster);
cluster = file->rwPosition.cluster;
} else {
clusCount = position / partition->bytesPerCluster;
cluster = file->startCluster;
}
nextCluster = _FAT_fat_nextCluster (partition, cluster);
while ((clusCount > 0) && (nextCluster != CLUSTER_FREE) && (nextCluster != CLUSTER_EOF)) {
clusCount--;