/**
* \brief check if there are anyone holding buf of this obj.
* If no one holding the buffers, expire the buffer.
* \return
* 0 : no one holding any buf of this obj
* >0 : the ref_count of buf which refer to this obj.
*/
int _CheckObjBufRef(uffs_Object *obj)
{
uffs_Device *dev = obj->dev;
uffs_Buf *buf;
TreeNode *node = obj->node;
u16 parent, serial, last_serial;
// check the DIR or FILE block
for (buf = uffs_BufFind(dev, obj->parent, obj->serial, UFFS_ALL_PAGES);
buf != NULL;
buf = uffs_BufFindFrom(dev, buf->next, obj->parent, obj->serial, UFFS_ALL_PAGES))
{
if (buf->ref_count > 0) {
// oops ...
uffs_Perror(UFFS_MSG_SERIOUS, "someone still hold buf parent = %d, serial = %d, ref_count",
obj->parent, obj->serial, buf->ref_count);
return buf->ref_count;
}
else {
buf->mark = UFFS_BUF_EMPTY;
}
}
if (buf == NULL || buf->ref_count == 0) {
// check the DATA block
if (obj->type == UFFS_TYPE_FILE && node->u.file.len > 0) {
parent = obj->serial;
last_serial = GetFdnByOfs(obj, node->u.file.len - 1);
for (serial = 1; serial <= last_serial; serial++) {
for (buf = uffs_BufFind(dev, parent, serial, UFFS_ALL_PAGES);
buf != NULL;
buf = uffs_BufFindFrom(dev, buf->next, parent, serial, UFFS_ALL_PAGES))
{
if (buf->ref_count != 0) {
// oops ...
uffs_Perror(UFFS_MSG_SERIOUS, "someone still hold buf parent = %d, serial = %d, ref_count",
parent, serial, buf->ref_count);
return buf->ref_count;
}
else {
buf->mark = UFFS_BUF_EMPTY;
}
}
}
}
}
return 0;
}
/** truncate obj without lock device */
static URET do_TruncateObject(uffs_Object *obj, u32 remain, RunOptionE run_opt)
{
uffs_Device *dev = obj->dev;
TreeNode *fnode = obj->node;
u16 fdn;
u32 flen;
u32 block_start;
TreeNode *node;
uffs_BlockInfo *bc;
uffs_Buf *buf;
u16 page;
int pos;
pos = obj->pos; // save current file position
if (obj->dev == NULL || obj->open_succ == U_FALSE || fnode == NULL) {
obj->err = UEBADF;
goto ext;
}
/* can't truncate a dir */
/* TODO: delete files under dir ? */
if (obj->type == UFFS_TYPE_DIR) {
obj->err = UEEXIST;
goto ext;
}
if (remain >= fnode->u.file.len) {
goto ext; //!< nothing to do ...
}
flen = fnode->u.file.len;
if (flen < remain) {
// file is shorter than 'reamin', fill the gap with '\0'
if (run_opt == eREAL_RUN) {
obj->pos = flen; // move file pointer to the end
if (do_WriteObject(obj, NULL, remain - flen) > 0) { // fill '\0' ...
uffs_Perror(UFFS_MSG_SERIOUS, "Write object not finished. expect %d but only %d wrote.",
remain - flen, fnode->u.file.len - flen);
obj->err = UEIOERR; // likely be an I/O error.
}
flen = obj->node->u.file.len;
}
}
else {
while (flen > remain) {
fdn = GetFdnByOfs(obj, flen - 1);
//uffs_BufFlushGroup(dev, obj->serial, fdn); //!< flush the buffer
block_start = GetStartOfDataBlock(obj, fdn);
if (remain <= block_start && fdn > 0) {
node = uffs_TreeFindDataNode(dev, obj->serial, fdn);
if (node == NULL) {
uffs_Perror(UFFS_MSG_SERIOUS,
"can't find data node when trancate obj.");
obj->err = UEIOERR;
goto ext;
}
bc = uffs_BlockInfoGet(dev, node->u.data.block);
if (bc == NULL) {
uffs_Perror(UFFS_MSG_SERIOUS,
"can't get block info when trancate obj.");
obj->err = UEIOERR;
goto ext;
}
for (page = 0; page < dev->attr->pages_per_block; page++) {
buf = uffs_BufFind(dev, fnode->u.file.serial, fdn, page);
if (buf) {
//!< ok, the buffer was loaded before ...
if (uffs_BufIsFree(buf) == U_FALSE) {
uffs_BlockInfoPut(dev, bc);
goto ext; //!< and someone is still holding the buffer,
// can't truncate it !!!
}
else if (run_opt == eREAL_RUN)
uffs_BufMarkEmpty(dev, buf); //!< discard the buffer
}
}
if (run_opt == eREAL_RUN) {
uffs_BreakFromEntry(dev, UFFS_TYPE_DATA, node);
uffs_FlashEraseBlock(dev, bc->block);
node->u.list.block = bc->block;
if (HAVE_BADBLOCK(dev))
uffs_BadBlockProcess(dev, node);
else
uffs_TreeInsertToErasedListTail(dev, node);
fnode->u.file.len = block_start;
}
flen = block_start;
uffs_BlockInfoPut(dev, bc);
}
else {
if (do_TruncateInternalWithBlockRecover(obj, fdn,
remain, run_opt) == U_SUCC) {
if (run_opt == eREAL_RUN)
fnode->u.file.len = remain;
flen = remain;
}
}
}
}
if (HAVE_BADBLOCK(dev))
uffs_BadBlockRecover(dev);
ext:
obj->pos = pos; // keep file pointer offset not changed.
uffs_Assert(fnode == obj->node, "obj->node change!\n");
return (obj->err == UENOERR ? U_SUCC : U_FAIL);
}
//
// To trancate the file, this is the last block to be trancated.
// We need to discard one or more pages within this block, hence requires 'block recover'.
//
static URET do_TruncateInternalWithBlockRecover(uffs_Object *obj,
u16 fdn, u32 remain, RunOptionE run_opt)
{
uffs_Device *dev = obj->dev;
TreeNode *fnode = obj->node;
u16 page_id, max_page_id;
TreeNode *node;
uffs_Buf *buf = NULL;
u8 type;
u32 block_start, block_offset;
u16 parent, serial;
int slot;
uffs_BlockInfo *bc = NULL;
int block = -1;
if (fdn == 0) {
node = fnode;
type = UFFS_TYPE_FILE;
max_page_id = obj->head_pages;
block_start = 0;
parent = node->u.file.parent;
serial = node->u.file.serial;
block = node->u.file.block;
}
else {
node = uffs_TreeFindDataNode(dev, fnode->u.file.serial, fdn);
if (node == NULL) {
obj->err = UEIOERR;
uffs_Perror(UFFS_MSG_SERIOUS,
"can't find data node when truncate obj");
goto ext;
}
block = node->u.data.block;
type = UFFS_TYPE_DATA;
max_page_id = dev->attr->pages_per_block - 1;
block_start = obj->head_pages * dev->com.pg_data_size +
(fdn - 1) * dev->com.pg_data_size *
dev->attr->pages_per_block;
parent = node->u.data.parent;
serial = node->u.data.serial;
}
if (run_opt == eDRY_RUN) {
// checking the buffer. this is the main reason why we need the 'dry run' mode.
for (page_id = 0; page_id <= max_page_id; page_id++) {
buf = uffs_BufFind(dev, parent, serial, page_id);
if (buf) {
//!< ok, the buffer was loaded before ...
if (uffs_BufIsFree(buf) == U_FALSE) {
obj->err = UEEXIST;
break; //!< and someone is still holding the buffer,
// can't truncate it !!!
}
}
}
buf = NULL;
goto ext;
}
// find the last page *after* truncate
block_offset = remain - block_start;
page_id = block_offset / dev->com.pg_data_size;
if (fdn == 0)
page_id++;
if (!uffs_Assert(page_id <= max_page_id, "fdn = %d, block_start = %d, remain = %d\n", fdn, block_start, remain)) {
obj->err = UEUNKNOWN_ERR;
goto ext;
}
// flush buffer before performing block recovery
uffs_BufFlushGroup(dev, parent, serial);
// load the last page
buf = uffs_BufGetEx(dev, type, node, page_id, obj->oflag);
if (buf == NULL) {
obj->err = UENOMEM;
uffs_Perror(UFFS_MSG_SERIOUS, "Can't get buf");
goto ext;
}
uffs_BufWrite(dev, buf, NULL, 0, 0); // just make this buf dirty
// lock the group
slot = uffs_BufFindGroupSlot(dev, parent, serial);
uffs_BufLockGroup(dev, slot);
if (remain == 0) // remain == 0: means discard all data in this block.
buf->data_len = 0;
else {
remain = (remain % dev->com.pg_data_size);
// remain == 0: means that we need to keep all data in this page.
buf->data_len = (remain == 0 ? dev->com.pg_data_size : remain);
}
/* mark this buf as UFFS_BUF_EXT_MARK_TRUNC_TAIL, when flushing
dirty buffers, UFFS will not do page recover for pages after
this buf page id (because this file is ended at this page) */
buf->ext_mark |= UFFS_BUF_EXT_MARK_TRUNC_TAIL;
uffs_BufPut(dev, buf);
// invalidate the rest page buf
page_id++;
for (; page_id <= max_page_id; page_id++) {
buf = uffs_BufFind(dev, parent, serial, page_id);
if (buf)
uffs_BufMarkEmpty(dev, buf);
}
// flush dirty buffer immediately, forcing block recovery.
uffs_BufFlushGroupEx(dev, parent, serial, U_TRUE);
// unlock the group
uffs_BufUnLockGroup(dev, slot);
// Invalidate block info cache for the 'old' block
bc = uffs_BlockInfoGet(dev, block);
if (bc) {
uffs_BlockInfoExpire(dev, bc, UFFS_ALL_PAGES);
uffs_BlockInfoPut(dev, bc);
}
ext:
return (obj->err == UENOERR ? U_SUCC : U_FAIL);
}
/**
* \brief delete uffs object
*
* \param[in] name full name of object
* \param[out] err return error code
*
* \return U_SUCC if object is deleted successfully.
* return U_FAIL if error happen, error code is set to *err.
*/
URET uffs_DeleteObject(const char * name, int *err)
{
uffs_Object *obj;
TreeNode *node;
uffs_Device *dev;
u16 block;
uffs_Buf *buf;
URET ret = U_FAIL;
obj = uffs_GetObject();
if (obj == NULL) {
if (err)
*err = UEMFILE;
goto err1;
}
if (uffs_OpenObject(obj, name, UO_RDWR|UO_DIR) == U_FAIL) {
if (uffs_OpenObject(obj, name, UO_RDWR) == U_FAIL) {
if (err)
*err = UENOENT;
goto err1;
}
}
uffs_TruncateObject(obj, 0);
uffs_ObjectDevLock(obj);
dev = obj->dev;
if (obj->type == UFFS_TYPE_DIR)
{
// if the dir is not empty, can't delete it.
node = uffs_TreeFindDirNodeWithParent(dev, obj->serial);
if (node != NULL)
{
if (err)
*err = UEACCES;
goto err; //have sub dirs ?
}
node = uffs_TreeFindFileNodeWithParent(dev, obj->serial);
if (node != NULL)
{
if (err)
*err = UEACCES;
goto err; //have sub files ?
}
}
block = GET_BLOCK_FROM_NODE(obj);
node = obj->node;
// before erase the block, we need to take care of the buffer ...
uffs_BufFlushAll(dev);
if (HAVE_BADBLOCK(dev))
uffs_BadBlockRecover(dev);
buf = uffs_BufFind(dev, obj->parent, obj->serial, 0);
if (buf) {
//need to expire this buffer ...
if (buf->ref_count != 0) {
//there is other obj for this file still in use ?
uffs_Perror(UFFS_ERR_NORMAL, "Try to delete object but still have buf referenced.");
if (err)
*err = UEACCES;
goto err;
}
buf->mark = UFFS_BUF_EMPTY; //!< make this buffer expired.
}
//TODO: need to take care of other obj->node ?
uffs_BreakFromEntry(dev, obj->type, node);
uffs_FlashEraseBlock(dev, block);
node->u.list.block = block;
if (HAVE_BADBLOCK(dev))
uffs_BadBlockProcess(dev, node);
else
uffs_TreeInsertToErasedListTail(dev, node);
ret = U_SUCC;
err:
uffs_ObjectDevUnLock(obj);
err1:
do_ReleaseObjectResource(obj);
uffs_PutObject(obj);
return ret;
}
/** truncate obj without lock device */
static URET do_TruncateObject(uffs_Object *obj, u32 remain, UBOOL dry_run)
{
uffs_Device *dev = obj->dev;
TreeNode *fnode = obj->node;
u16 fdn;
u32 flen;
u32 block_start;
TreeNode *node;
uffs_BlockInfo *bc;
uffs_Buf *buf;
u16 page;
if (obj->dev == NULL || obj->open_succ == U_FALSE || fnode == NULL) {
obj->err = UEBADF;
goto ext;
}
/* can't truncate a dir */
/* TODO: delete files under dir ? */
if (obj->type == UFFS_TYPE_DIR) {
obj->err = UEEXIST;
goto ext;
}
if (remain >= fnode->u.file.len) {
goto ext; //!< nothing to do ...
}
flen = fnode->u.file.len;
while (flen > remain) {
fdn = GetFdnByOfs(obj, flen - 1);
//uffs_BufFlushGroup(dev, obj->serial, fdn); //!< flush the buffer
block_start = GetStartOfDataBlock(obj, fdn);
if (remain <= block_start && fdn > 0) {
node = uffs_TreeFindDataNode(dev, obj->serial, fdn);
if (node == NULL) {
uffs_Perror(UFFS_ERR_SERIOUS, "can't find data node when trancate obj.");
obj->err = UEIOERR;
goto ext;
}
bc = uffs_BlockInfoGet(dev, node->u.data.block);
if (bc == NULL) {
uffs_Perror(UFFS_ERR_SERIOUS, "can't get block info when trancate obj.");
obj->err = UEIOERR;
goto ext;
}
for (page = 0; page < dev->attr->pages_per_block; page++) {
buf = uffs_BufFind(dev, fnode->u.file.serial, fdn, page);
if (buf) { //!< ok, the buffer was loaded before ...
if (uffs_BufIsFree(buf) == U_FALSE) {
uffs_BlockInfoPut(dev, bc);
goto ext; //!< and someone is still holding the buffer, can't truncate it !!!
}
else if (dry_run == U_FALSE)
uffs_BufMarkEmpty(dev, buf); //!< discard the buffer
}
}
if (dry_run == U_FALSE) {
uffs_BlockInfoExpire(dev, bc, UFFS_ALL_PAGES);
uffs_BreakFromEntry(dev, UFFS_TYPE_DATA, node);
uffs_FlashEraseBlock(dev, bc->block);
node->u.list.block = bc->block;
if (HAVE_BADBLOCK(dev))
uffs_BadBlockProcess(dev, node);
else
uffs_TreeInsertToErasedListTail(dev, node);
uffs_BlockInfoPut(dev, bc);
fnode->u.file.len = block_start;
}
else {
uffs_BlockInfoPut(dev, bc);
}
flen = block_start;
}
else {
if (do_TruncateInternalWithBlockRecover(obj, fdn, remain, dry_run) == U_SUCC) {
if (dry_run == U_FALSE)
fnode->u.file.len = remain;
flen = remain;
}
}
}
if (HAVE_BADBLOCK(dev))
uffs_BadBlockRecover(dev);
ext:
return (obj->err == UENOERR ? U_SUCC : U_FAIL);
}
static URET do_TruncateInternalWithBlockRecover(uffs_Object *obj, u16 fdn, u32 remain, UBOOL dry_run)
{
uffs_Device *dev = obj->dev;
TreeNode *fnode = obj->node;
u16 page_id, max_page_id;
TreeNode *node;
uffs_Buf *buf = NULL;
u8 type;
u32 block_start;
u16 parent, serial;
int slot;
if (fdn == 0) {
node = fnode;
type = UFFS_TYPE_FILE;
max_page_id = obj->head_pages;
block_start = 0;
parent = node->u.file.parent;
serial = node->u.file.serial;
}
else {
node = uffs_TreeFindDataNode(dev, fnode->u.file.serial, fdn);
if (node == NULL) {
obj->err = UEIOERR;
uffs_Perror(UFFS_ERR_SERIOUS, "can't find data node when truncate obj");
goto ext;
}
type = UFFS_TYPE_DATA;
max_page_id = dev->attr->pages_per_block - 1;
block_start = obj->head_pages * dev->com.pg_data_size + (fdn - 1) * dev->com.pg_data_size * dev->attr->pages_per_block;
parent = node->u.data.parent;
serial = node->u.data.serial;
}
if (dry_run == U_TRUE) {
// checking the buffer. this is the main reason why we need the 'dry run' mode.
for (page_id = 0; page_id <= max_page_id; page_id++) {
buf = uffs_BufFind(dev, parent, serial, page_id);
if (buf) { //!< ok, the buffer was loaded before ...
if (uffs_BufIsFree(buf) == U_FALSE) {
obj->err = UEEXIST;
break; //!< and someone is still holding the buffer, can't truncate it !!!
}
}
}
buf = NULL;
goto ext;
}
// find the last page after truncate
for (page_id = (fdn == 0 ? 1 : 0); page_id <= max_page_id; page_id++) {
if (block_start + (page_id + 1) * dev->com.pg_data_size >= remain)
break;
}
if (page_id > max_page_id) {
obj->err = UEUNKNOWN;
uffs_Perror(UFFS_ERR_SERIOUS, "Overflow");
goto ext;
}
// flush buffer before performing block recovery
uffs_BufFlushGroup(dev, parent, serial);
// load the last page
buf = uffs_BufGetEx(dev, type, node, page_id);
if (buf == NULL) {
obj->err = UENOMEM;
uffs_Perror(UFFS_ERR_SERIOUS, "Can't get buf");
goto ext;
}
uffs_BufWrite(dev, buf, NULL, 0, 0); // just make this buf dirty
// lock the group
slot = uffs_BufFindGroupSlot(dev, parent, serial);
uffs_BufLockGroup(dev, slot);
if (remain == 0)
buf->data_len = 0;
else {
remain = (remain % dev->com.pg_data_size);
buf->data_len = (remain == 0 ? dev->com.pg_data_size : 0);
}
buf->ext_mark |= UFFS_BUF_EXT_MARK_TRUNC_TAIL;
uffs_BufPut(dev, buf);
// invalidate the rest page buf
page_id++;
for (; page_id <= max_page_id; page_id++) {
buf = uffs_BufFind(dev, parent, serial, page_id);
if (buf)
uffs_BufMarkEmpty(dev, buf);
}
// flush dirty buffer immediately, forcing block recovery.
uffs_BufFlushGroupEx(dev, parent, serial, U_TRUE);
// unlock the group
uffs_BufUnLockGroup(dev, slot);
ext:
return (obj->err == UENOERR ? U_SUCC : U_FAIL);
}
