diff options
Diffstat (limited to 'libsparse/backed_block.cpp')
-rw-r--r-- | libsparse/backed_block.cpp | 629 |
1 files changed, 302 insertions, 327 deletions
diff --git a/libsparse/backed_block.cpp b/libsparse/backed_block.cpp index fb26d1a6e..7f5632eea 100644 --- a/libsparse/backed_block.cpp +++ b/libsparse/backed_block.cpp @@ -24,382 +24,357 @@ #include "sparse_defs.h" struct backed_block { - unsigned int block; - unsigned int len; - enum backed_block_type type; - union { - struct { - void *data; - } data; - struct { - char *filename; - int64_t offset; - } file; - struct { - int fd; - int64_t offset; - } fd; - struct { - uint32_t val; - } fill; - }; - struct backed_block *next; + unsigned int block; + unsigned int len; + enum backed_block_type type; + union { + struct { + void* data; + } data; + struct { + char* filename; + int64_t offset; + } file; + struct { + int fd; + int64_t offset; + } fd; + struct { + uint32_t val; + } fill; + }; + struct backed_block* next; }; struct backed_block_list { - struct backed_block *data_blocks; - struct backed_block *last_used; - unsigned int block_size; + struct backed_block* data_blocks; + struct backed_block* last_used; + unsigned int block_size; }; -struct backed_block *backed_block_iter_new(struct backed_block_list *bbl) -{ - return bbl->data_blocks; +struct backed_block* backed_block_iter_new(struct backed_block_list* bbl) { + return bbl->data_blocks; } -struct backed_block *backed_block_iter_next(struct backed_block *bb) -{ - return bb->next; +struct backed_block* backed_block_iter_next(struct backed_block* bb) { + return bb->next; } -unsigned int backed_block_len(struct backed_block *bb) -{ - return bb->len; +unsigned int backed_block_len(struct backed_block* bb) { + return bb->len; } -unsigned int backed_block_block(struct backed_block *bb) -{ - return bb->block; +unsigned int backed_block_block(struct backed_block* bb) { + return bb->block; } -void *backed_block_data(struct backed_block *bb) -{ - assert(bb->type == BACKED_BLOCK_DATA); - return bb->data.data; +void* backed_block_data(struct backed_block* bb) { + assert(bb->type == BACKED_BLOCK_DATA); + return bb->data.data; } -const char *backed_block_filename(struct backed_block *bb) -{ - assert(bb->type == BACKED_BLOCK_FILE); - return bb->file.filename; +const char* backed_block_filename(struct backed_block* bb) { + assert(bb->type == BACKED_BLOCK_FILE); + return bb->file.filename; } -int backed_block_fd(struct backed_block *bb) -{ - assert(bb->type == BACKED_BLOCK_FD); - return bb->fd.fd; +int backed_block_fd(struct backed_block* bb) { + assert(bb->type == BACKED_BLOCK_FD); + return bb->fd.fd; } -int64_t backed_block_file_offset(struct backed_block *bb) -{ - assert(bb->type == BACKED_BLOCK_FILE || bb->type == BACKED_BLOCK_FD); - if (bb->type == BACKED_BLOCK_FILE) { - return bb->file.offset; - } else { /* bb->type == BACKED_BLOCK_FD */ - return bb->fd.offset; - } +int64_t backed_block_file_offset(struct backed_block* bb) { + assert(bb->type == BACKED_BLOCK_FILE || bb->type == BACKED_BLOCK_FD); + if (bb->type == BACKED_BLOCK_FILE) { + return bb->file.offset; + } else { /* bb->type == BACKED_BLOCK_FD */ + return bb->fd.offset; + } } -uint32_t backed_block_fill_val(struct backed_block *bb) -{ - assert(bb->type == BACKED_BLOCK_FILL); - return bb->fill.val; +uint32_t backed_block_fill_val(struct backed_block* bb) { + assert(bb->type == BACKED_BLOCK_FILL); + return bb->fill.val; } -enum backed_block_type backed_block_type(struct backed_block *bb) -{ - return bb->type; +enum backed_block_type backed_block_type(struct backed_block* bb) { + return bb->type; } -void backed_block_destroy(struct backed_block *bb) -{ - if (bb->type == BACKED_BLOCK_FILE) { - free(bb->file.filename); - } +void backed_block_destroy(struct backed_block* bb) { + if (bb->type == BACKED_BLOCK_FILE) { + free(bb->file.filename); + } - free(bb); + free(bb); } -struct backed_block_list *backed_block_list_new(unsigned int block_size) -{ - struct backed_block_list *b = reinterpret_cast<backed_block_list*>( - calloc(sizeof(struct backed_block_list), 1)); - b->block_size = block_size; - return b; +struct backed_block_list* backed_block_list_new(unsigned int block_size) { + struct backed_block_list* b = + reinterpret_cast<backed_block_list*>(calloc(sizeof(struct backed_block_list), 1)); + b->block_size = block_size; + return b; } -void backed_block_list_destroy(struct backed_block_list *bbl) -{ - if (bbl->data_blocks) { - struct backed_block *bb = bbl->data_blocks; - while (bb) { - struct backed_block *next = bb->next; - backed_block_destroy(bb); - bb = next; - } - } - - free(bbl); +void backed_block_list_destroy(struct backed_block_list* bbl) { + if (bbl->data_blocks) { + struct backed_block* bb = bbl->data_blocks; + while (bb) { + struct backed_block* next = bb->next; + backed_block_destroy(bb); + bb = next; + } + } + + free(bbl); } -void backed_block_list_move(struct backed_block_list *from, - struct backed_block_list *to, struct backed_block *start, - struct backed_block *end) -{ - struct backed_block *bb; - - if (start == NULL) { - start = from->data_blocks; - } - - if (!end) { - for (end = start; end && end->next; end = end->next) - ; - } - - if (start == NULL || end == NULL) { - return; - } - - from->last_used = NULL; - to->last_used = NULL; - if (from->data_blocks == start) { - from->data_blocks = end->next; - } else { - for (bb = from->data_blocks; bb; bb = bb->next) { - if (bb->next == start) { - bb->next = end->next; - break; - } - } - } - - if (!to->data_blocks) { - to->data_blocks = start; - end->next = NULL; - } else { - for (bb = to->data_blocks; bb; bb = bb->next) { - if (!bb->next || bb->next->block > start->block) { - end->next = bb->next; - bb->next = start; - break; - } - } - } +void backed_block_list_move(struct backed_block_list* from, struct backed_block_list* to, + struct backed_block* start, struct backed_block* end) { + struct backed_block* bb; + + if (start == NULL) { + start = from->data_blocks; + } + + if (!end) { + for (end = start; end && end->next; end = end->next) + ; + } + + if (start == NULL || end == NULL) { + return; + } + + from->last_used = NULL; + to->last_used = NULL; + if (from->data_blocks == start) { + from->data_blocks = end->next; + } else { + for (bb = from->data_blocks; bb; bb = bb->next) { + if (bb->next == start) { + bb->next = end->next; + break; + } + } + } + + if (!to->data_blocks) { + to->data_blocks = start; + end->next = NULL; + } else { + for (bb = to->data_blocks; bb; bb = bb->next) { + if (!bb->next || bb->next->block > start->block) { + end->next = bb->next; + bb->next = start; + break; + } + } + } } /* may free b */ -static int merge_bb(struct backed_block_list *bbl, - struct backed_block *a, struct backed_block *b) -{ - unsigned int block_len; - - /* Block doesn't exist (possible if one block is the last block) */ - if (!a || !b) { - return -EINVAL; - } - - assert(a->block < b->block); - - /* Blocks are of different types */ - if (a->type != b->type) { - return -EINVAL; - } - - /* Blocks are not adjacent */ - block_len = a->len / bbl->block_size; /* rounds down */ - if (a->block + block_len != b->block) { - return -EINVAL; - } - - switch (a->type) { - case BACKED_BLOCK_DATA: - /* Don't support merging data for now */ - return -EINVAL; - case BACKED_BLOCK_FILL: - if (a->fill.val != b->fill.val) { - return -EINVAL; - } - break; - case BACKED_BLOCK_FILE: - /* Already make sure b->type is BACKED_BLOCK_FILE */ - if (strcmp(a->file.filename, b->file.filename) || - a->file.offset + a->len != b->file.offset) { - return -EINVAL; - } - break; - case BACKED_BLOCK_FD: - if (a->fd.fd != b->fd.fd || - a->fd.offset + a->len != b->fd.offset) { - return -EINVAL; - } - break; - } - - /* Blocks are compatible and adjacent, with a before b. Merge b into a, - * and free b */ - a->len += b->len; - a->next = b->next; - - backed_block_destroy(b); - - return 0; +static int merge_bb(struct backed_block_list* bbl, struct backed_block* a, struct backed_block* b) { + unsigned int block_len; + + /* Block doesn't exist (possible if one block is the last block) */ + if (!a || !b) { + return -EINVAL; + } + + assert(a->block < b->block); + + /* Blocks are of different types */ + if (a->type != b->type) { + return -EINVAL; + } + + /* Blocks are not adjacent */ + block_len = a->len / bbl->block_size; /* rounds down */ + if (a->block + block_len != b->block) { + return -EINVAL; + } + + switch (a->type) { + case BACKED_BLOCK_DATA: + /* Don't support merging data for now */ + return -EINVAL; + case BACKED_BLOCK_FILL: + if (a->fill.val != b->fill.val) { + return -EINVAL; + } + break; + case BACKED_BLOCK_FILE: + /* Already make sure b->type is BACKED_BLOCK_FILE */ + if (strcmp(a->file.filename, b->file.filename) || a->file.offset + a->len != b->file.offset) { + return -EINVAL; + } + break; + case BACKED_BLOCK_FD: + if (a->fd.fd != b->fd.fd || a->fd.offset + a->len != b->fd.offset) { + return -EINVAL; + } + break; + } + + /* Blocks are compatible and adjacent, with a before b. Merge b into a, + * and free b */ + a->len += b->len; + a->next = b->next; + + backed_block_destroy(b); + + return 0; } -static int queue_bb(struct backed_block_list *bbl, struct backed_block *new_bb) -{ - struct backed_block *bb; - - if (bbl->data_blocks == NULL) { - bbl->data_blocks = new_bb; - return 0; - } - - if (bbl->data_blocks->block > new_bb->block) { - new_bb->next = bbl->data_blocks; - bbl->data_blocks = new_bb; - return 0; - } - - /* Optimization: blocks are mostly queued in sequence, so save the - pointer to the last bb that was added, and start searching from - there if the next block number is higher */ - if (bbl->last_used && new_bb->block > bbl->last_used->block) - bb = bbl->last_used; - else - bb = bbl->data_blocks; - bbl->last_used = new_bb; - - for (; bb->next && bb->next->block < new_bb->block; bb = bb->next) - ; - - if (bb->next == NULL) { - bb->next = new_bb; - } else { - new_bb->next = bb->next; - bb->next = new_bb; - } - - merge_bb(bbl, new_bb, new_bb->next); - if (!merge_bb(bbl, bb, new_bb)) { - /* new_bb destroyed, point to retained as last_used */ - bbl->last_used = bb; - } - - return 0; +static int queue_bb(struct backed_block_list* bbl, struct backed_block* new_bb) { + struct backed_block* bb; + + if (bbl->data_blocks == NULL) { + bbl->data_blocks = new_bb; + return 0; + } + + if (bbl->data_blocks->block > new_bb->block) { + new_bb->next = bbl->data_blocks; + bbl->data_blocks = new_bb; + return 0; + } + + /* Optimization: blocks are mostly queued in sequence, so save the + pointer to the last bb that was added, and start searching from + there if the next block number is higher */ + if (bbl->last_used && new_bb->block > bbl->last_used->block) + bb = bbl->last_used; + else + bb = bbl->data_blocks; + bbl->last_used = new_bb; + + for (; bb->next && bb->next->block < new_bb->block; bb = bb->next) + ; + + if (bb->next == NULL) { + bb->next = new_bb; + } else { + new_bb->next = bb->next; + bb->next = new_bb; + } + + merge_bb(bbl, new_bb, new_bb->next); + if (!merge_bb(bbl, bb, new_bb)) { + /* new_bb destroyed, point to retained as last_used */ + bbl->last_used = bb; + } + + return 0; } /* Queues a fill block of memory to be written to the specified data blocks */ -int backed_block_add_fill(struct backed_block_list *bbl, unsigned int fill_val, - unsigned int len, unsigned int block) -{ - struct backed_block *bb = reinterpret_cast<backed_block*>(calloc(1, sizeof(struct backed_block))); - if (bb == NULL) { - return -ENOMEM; - } - - bb->block = block; - bb->len = len; - bb->type = BACKED_BLOCK_FILL; - bb->fill.val = fill_val; - bb->next = NULL; - - return queue_bb(bbl, bb); +int backed_block_add_fill(struct backed_block_list* bbl, unsigned int fill_val, unsigned int len, + unsigned int block) { + struct backed_block* bb = reinterpret_cast<backed_block*>(calloc(1, sizeof(struct backed_block))); + if (bb == NULL) { + return -ENOMEM; + } + + bb->block = block; + bb->len = len; + bb->type = BACKED_BLOCK_FILL; + bb->fill.val = fill_val; + bb->next = NULL; + + return queue_bb(bbl, bb); } /* Queues a block of memory to be written to the specified data blocks */ -int backed_block_add_data(struct backed_block_list *bbl, void *data, - unsigned int len, unsigned int block) -{ - struct backed_block *bb = reinterpret_cast<backed_block*>(calloc(1, sizeof(struct backed_block))); - if (bb == NULL) { - return -ENOMEM; - } - - bb->block = block; - bb->len = len; - bb->type = BACKED_BLOCK_DATA; - bb->data.data = data; - bb->next = NULL; - - return queue_bb(bbl, bb); +int backed_block_add_data(struct backed_block_list* bbl, void* data, unsigned int len, + unsigned int block) { + struct backed_block* bb = reinterpret_cast<backed_block*>(calloc(1, sizeof(struct backed_block))); + if (bb == NULL) { + return -ENOMEM; + } + + bb->block = block; + bb->len = len; + bb->type = BACKED_BLOCK_DATA; + bb->data.data = data; + bb->next = NULL; + + return queue_bb(bbl, bb); } /* Queues a chunk of a file on disk to be written to the specified data blocks */ -int backed_block_add_file(struct backed_block_list *bbl, const char *filename, - int64_t offset, unsigned int len, unsigned int block) -{ - struct backed_block *bb = reinterpret_cast<backed_block*>(calloc(1, sizeof(struct backed_block))); - if (bb == NULL) { - return -ENOMEM; - } - - bb->block = block; - bb->len = len; - bb->type = BACKED_BLOCK_FILE; - bb->file.filename = strdup(filename); - bb->file.offset = offset; - bb->next = NULL; - - return queue_bb(bbl, bb); +int backed_block_add_file(struct backed_block_list* bbl, const char* filename, int64_t offset, + unsigned int len, unsigned int block) { + struct backed_block* bb = reinterpret_cast<backed_block*>(calloc(1, sizeof(struct backed_block))); + if (bb == NULL) { + return -ENOMEM; + } + + bb->block = block; + bb->len = len; + bb->type = BACKED_BLOCK_FILE; + bb->file.filename = strdup(filename); + bb->file.offset = offset; + bb->next = NULL; + + return queue_bb(bbl, bb); } /* Queues a chunk of a fd to be written to the specified data blocks */ -int backed_block_add_fd(struct backed_block_list *bbl, int fd, int64_t offset, - unsigned int len, unsigned int block) -{ - struct backed_block *bb = reinterpret_cast<backed_block*>(calloc(1, sizeof(struct backed_block))); - if (bb == NULL) { - return -ENOMEM; - } - - bb->block = block; - bb->len = len; - bb->type = BACKED_BLOCK_FD; - bb->fd.fd = fd; - bb->fd.offset = offset; - bb->next = NULL; - - return queue_bb(bbl, bb); +int backed_block_add_fd(struct backed_block_list* bbl, int fd, int64_t offset, unsigned int len, + unsigned int block) { + struct backed_block* bb = reinterpret_cast<backed_block*>(calloc(1, sizeof(struct backed_block))); + if (bb == NULL) { + return -ENOMEM; + } + + bb->block = block; + bb->len = len; + bb->type = BACKED_BLOCK_FD; + bb->fd.fd = fd; + bb->fd.offset = offset; + bb->next = NULL; + + return queue_bb(bbl, bb); } -int backed_block_split(struct backed_block_list *bbl, struct backed_block *bb, - unsigned int max_len) -{ - struct backed_block *new_bb; - - max_len = ALIGN_DOWN(max_len, bbl->block_size); - - if (bb->len <= max_len) { - return 0; - } - - new_bb = reinterpret_cast<backed_block*>(malloc(sizeof(struct backed_block))); - if (new_bb == NULL) { - return -ENOMEM; - } - - *new_bb = *bb; - - new_bb->len = bb->len - max_len; - new_bb->block = bb->block + max_len / bbl->block_size; - new_bb->next = bb->next; - bb->next = new_bb; - bb->len = max_len; - - switch (bb->type) { - case BACKED_BLOCK_DATA: - new_bb->data.data = (char *)bb->data.data + max_len; - break; - case BACKED_BLOCK_FILE: - new_bb->file.offset += max_len; - break; - case BACKED_BLOCK_FD: - new_bb->fd.offset += max_len; - break; - case BACKED_BLOCK_FILL: - break; - } - - return 0; +int backed_block_split(struct backed_block_list* bbl, struct backed_block* bb, + unsigned int max_len) { + struct backed_block* new_bb; + + max_len = ALIGN_DOWN(max_len, bbl->block_size); + + if (bb->len <= max_len) { + return 0; + } + + new_bb = reinterpret_cast<backed_block*>(malloc(sizeof(struct backed_block))); + if (new_bb == NULL) { + return -ENOMEM; + } + + *new_bb = *bb; + + new_bb->len = bb->len - max_len; + new_bb->block = bb->block + max_len / bbl->block_size; + new_bb->next = bb->next; + bb->next = new_bb; + bb->len = max_len; + + switch (bb->type) { + case BACKED_BLOCK_DATA: + new_bb->data.data = (char*)bb->data.data + max_len; + break; + case BACKED_BLOCK_FILE: + new_bb->file.offset += max_len; + break; + case BACKED_BLOCK_FD: + new_bb->fd.offset += max_len; + break; + case BACKED_BLOCK_FILL: + break; + } + + return 0; } |