refactor(lsm): clean up disk write code

lsm
Jef Roosens 2023-11-09 21:07:51 +01:00
parent 4fb127d9db
commit 715e1f9a58
Signed by: Jef Roosens
GPG Key ID: 02D4C0997E74717B
2 changed files with 47 additions and 43 deletions

View File

@ -24,7 +24,7 @@ typedef enum lander_attr_type : uint8_t {
lander_attr_type_url = 2,
} lander_attr_type;
typedef enum lander_entry_type {
typedef enum lander_entry_type : uint8_t {
lander_entry_type_redirect = 0,
lander_entry_type_paste = 1,
} lander_entry_type;

View File

@ -1,31 +1,39 @@
#include "lsm/store_internal.h"
static lsm_error lsm_entry_write_single(FILE *f, uint64_t size, void *val) {
size_t res = fwrite(val, size, 1, f);
static lsm_error lsm_fwrite(uint64_t *sum, FILE *f, uint64_t size,
uint64_t count, void *val) {
size_t res = fwrite(val, size, count, f);
if (res == 0) {
if (res < count) {
return lsm_error_failed_io;
}
if (sum != NULL) {
*sum += size * count;
}
return lsm_error_ok;
}
static lsm_error lsm_entry_write_uint64_t(FILE *f, uint64_t num) {
return lsm_entry_write_single(f, sizeof(uint64_t), &num);
}
static lsm_error lsm_write_str(uint64_t *sum, FILE *f, lsm_str *s) {
uint64_t len = lsm_str_len(s);
LSM_RES(lsm_fwrite(sum, f, sizeof(uint64_t), 1, &len));
static lsm_error lsm_entry_write_str(FILE *f, lsm_str *s) {
uint64_t to_write = lsm_str_len(s);
uint64_t written = 0;
do {
written += fwrite(lsm_str_ptr(s), sizeof(char), to_write - written, f);
} while (written < to_write);
written += fwrite(lsm_str_ptr(s), sizeof(char), len - written, f);
} while (written < len);
if (sum != NULL) {
*sum += len * sizeof(char);
}
return lsm_error_ok;
}
static lsm_error lsm_seek(FILE *f, uint64_t pos) {
static lsm_error lsm_fseek(FILE *f, uint64_t pos) {
if (fseek(f, pos, SEEK_SET) != 0) {
return lsm_error_failed_io;
}
@ -35,24 +43,17 @@ static lsm_error lsm_seek(FILE *f, uint64_t pos) {
lsm_error lsm_entry_write_db(uint64_t *size, FILE *db_file, lsm_entry *entry,
uint64_t pos) {
LSM_RES(lsm_seek(db_file, pos));
*size = 0;
LSM_RES(lsm_entry_write_uint64_t(db_file, entry->data_len));
LSM_RES(lsm_fseek(db_file, pos));
LSM_RES(
lsm_entry_write_single(db_file, sizeof(uint8_t), &entry->attrs.count));
*size = sizeof(uint64_t) + sizeof(uint8_t);
LSM_RES(lsm_fwrite(size, db_file, sizeof(uint64_t), 1, &entry->data_len));
LSM_RES(lsm_fwrite(size, db_file, sizeof(uint8_t), 1, &entry->attrs.count));
for (uint8_t i = 0; i < entry->attrs.count; i++) {
// Write attribute type, length & value
LSM_RES(lsm_entry_write_single(db_file, sizeof(uint8_t),
LSM_RES(lsm_fwrite(size, db_file, sizeof(uint8_t), 1,
&entry->attrs.items[i].type));
LSM_RES(lsm_entry_write_uint64_t(db_file,
lsm_str_len(entry->attrs.items[i].str)));
LSM_RES(lsm_entry_write_str(db_file, entry->attrs.items[i].str));
*size += sizeof(uint8_t) + sizeof(uint64_t) +
lsm_str_len(entry->attrs.items[i].str) * sizeof(char);
LSM_RES(lsm_write_str(size, db_file, entry->attrs.items[i].str));
}
return lsm_error_ok;
@ -60,13 +61,13 @@ lsm_error lsm_entry_write_db(uint64_t *size, FILE *db_file, lsm_entry *entry,
lsm_error lsm_entry_write_idx(uint64_t *size, FILE *idx_file, lsm_entry *entry,
uint64_t offset, uint64_t len, uint64_t pos) {
LSM_RES(lsm_seek(idx_file, pos));
LSM_RES(lsm_entry_write_uint64_t(idx_file, lsm_str_len(entry->key)));
LSM_RES(lsm_entry_write_str(idx_file, entry->key));
LSM_RES(lsm_entry_write_uint64_t(idx_file, offset));
LSM_RES(lsm_entry_write_uint64_t(idx_file, len));
*size = 0;
*size = 3 * sizeof(uint64_t) + lsm_str_len(entry->key) * sizeof(char);
LSM_RES(lsm_fseek(idx_file, pos));
LSM_RES(lsm_write_str(size, idx_file, entry->key));
LSM_RES(lsm_fwrite(size, idx_file, sizeof(uint64_t), 1, &offset));
LSM_RES(lsm_fwrite(size, idx_file, sizeof(uint64_t), 1, &len));
return lsm_error_ok;
}
@ -74,9 +75,10 @@ lsm_error lsm_entry_write_idx(uint64_t *size, FILE *idx_file, lsm_entry *entry,
lsm_error lsm_entry_sync(lsm_store *store, lsm_entry_handle *handle) {
pthread_mutex_lock(&store->db_lock);
uint64_t entry_size;
lsm_error res = lsm_entry_write_db(
&entry_size, store->db_file, handle->wrapper->entry, store->db_file_size);
uint64_t db_entry_size;
lsm_error res =
lsm_entry_write_db(&db_entry_size, store->db_file, handle->wrapper->entry,
store->db_file_size);
fflush(store->db_file);
if (res != lsm_error_ok) {
@ -85,17 +87,17 @@ lsm_error lsm_entry_sync(lsm_store *store, lsm_entry_handle *handle) {
return res;
}
uint64_t entry_index = store->db_file_size;
store->db_file_size += entry_size;
uint64_t db_entry_index = store->db_file_size;
pthread_mutex_unlock(&store->db_lock);
// Append entry to index file
pthread_mutex_lock(&store->idx_lock);
res =
lsm_entry_write_idx(&entry_size, store->idx_file, handle->wrapper->entry,
entry_index, entry_size, store->idx_file_size);
uint64_t idx_entry_size;
res = lsm_entry_write_idx(&idx_entry_size, store->idx_file,
handle->wrapper->entry, db_entry_index,
db_entry_size, store->idx_file_size);
if (res == lsm_error_ok) {
// Update the counter at the beginning of the file
@ -103,14 +105,16 @@ lsm_error lsm_entry_sync(lsm_store *store, lsm_entry_handle *handle) {
uint64_t new_block_count = store->idx_file_block_count + 1;
res = lsm_entry_write_uint64_t(store->idx_file, new_block_count);
res = lsm_fwrite(NULL, store->idx_file, sizeof(uint64_t), 1,
&new_block_count);
if (res == lsm_error_ok) {
// Only if we successfully updated the on-disk counter do we make the code
// aware that the file's size has increased. This way, if a write to the
// aware that the files' sizes have increased. This way, if a write to the
// counter fails, the code will simply reuse the already written content.
store->idx_file_size += entry_size;
store->idx_file_size += idx_entry_size;
store->idx_file_block_count = new_block_count;
store->db_file_size += db_entry_size;
}
}