int journal_close(journal_t *journal)
{
/* Check journal. */
if (journal == NULL) {
return KNOT_EINVAL;
}
/* Check if lazy. */
int ret = KNOT_EOK;
if (journal->fd < 0) {
free(journal->path);
} else {
/* Recalculate CRC. */
ret = journal_update_crc(journal->fd);
/* Unlock journal file. */
journal->fl.l_type = F_UNLCK;
fcntl(journal->fd, F_SETLK, &journal->fl);
dbg_journal("journal: unlocked journal %p\n", journal);
/* Close file. */
close(journal->fd);
}
dbg_journal("journal: closed journal %p\n", journal);
/* Free allocated resources. */
free(journal);
return ret;
}
/*! \brief Close journal file. */
static int journal_close_file(journal_t *journal)
{
/* Check journal. */
if (journal == NULL) {
return KNOT_EINVAL;
}
/* Recalculate CRC. */
int ret = journal_update_crc(journal->fd);
/* Close file. */
close(journal->fd);
journal->fd = -1;
/* Free nodes. */
free(journal->nodes);
journal->nodes = NULL;
dbg_journal("journal: closed journal %p\n", journal);
return ret;
}
int journal_create(const char *fn, uint16_t max_nodes)
{
if (fn == NULL) {
return KNOT_EINVAL;
}
/* File lock. */
struct flock fl;
memset(&fl, 0, sizeof(struct flock));
fl.l_type = F_WRLCK;
fl.l_whence = SEEK_SET;
fl.l_start = 0;
fl.l_len = 0;
fl.l_pid = getpid();
/* Create journal file. */
int fd = open(fn, O_RDWR|O_CREAT|O_TRUNC, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP);
if (fd < 0) {
dbg_journal("journal: failed to create file '%s'\n", fn);
return knot_map_errno(errno);
}
/* Lock. */
fcntl(fd, F_SETLKW, &fl);
fl.l_type = F_UNLCK;
/* Create journal header. */
dbg_journal("journal: creating header\n");
const char magic[MAGIC_LENGTH] = JOURNAL_MAGIC;
if (!sfwrite(magic, MAGIC_LENGTH, fd)) {
fcntl(fd, F_SETLK, &fl);
close(fd);
remove(fn);
return KNOT_ERROR;
}
crc_t crc = crc_init();
if (!sfwrite(&crc, sizeof(crc_t), fd)) {
fcntl(fd, F_SETLK, &fl);
close(fd);
remove(fn);
return KNOT_ERROR;
}
if (!sfwrite(&max_nodes, sizeof(uint16_t), fd)) {
fcntl(fd, F_SETLK, &fl);
close(fd);
remove(fn);
return KNOT_ERROR;
}
/* Create node queue head + tail.
* qhead points to least recent node
* qtail points to next free node
* qhead == qtail means empty queue
*/
uint16_t zval = 0;
if (!sfwrite(&zval, sizeof(uint16_t), fd)) {
fcntl(fd, F_SETLK, &fl);
close(fd);
remove(fn);
return KNOT_ERROR;
}
if (!sfwrite(&zval, sizeof(uint16_t), fd)) {
fcntl(fd, F_SETLK, &fl);
close(fd);
remove(fn);
return KNOT_ERROR;
}
dbg_journal_verb("journal: creating free segment descriptor\n");
/* Create free segment descriptor. */
journal_node_t jn;
memset(&jn, 0, sizeof(journal_node_t));
jn.id = 0;
jn.flags = JOURNAL_VALID;
jn.pos = JOURNAL_HSIZE + (max_nodes + 1) * sizeof(journal_node_t);
jn.len = 0;
if (!sfwrite(&jn, sizeof(journal_node_t), fd)) {
fcntl(fd, F_SETLK, &fl);
close(fd);
remove(fn);
return KNOT_ERROR;
}
/* Create nodes. */
dbg_journal("journal: creating node table, size=%u\n", max_nodes);
memset(&jn, 0, sizeof(journal_node_t));
for(uint16_t i = 0; i < max_nodes; ++i) {
if (!sfwrite(&jn, sizeof(journal_node_t), fd)) {
fcntl(fd, F_SETLK, &fl);
close(fd);
if (remove(fn) < 0) {
dbg_journal("journal: failed to remove journal file after error\n");
}
return KNOT_ERROR;
}
}
/* Recalculate CRC. */
if (journal_update_crc(fd) != KNOT_EOK) {
fcntl(fd, F_SETLK, &fl);
close(fd);
if(remove(fn) < 0) {
dbg_journal("journal: failed to remove journal file after error\n");
}
return KNOT_ERROR;
}
/* Unlock and close. */
fcntl(fd, F_SETLK, &fl);
close(fd);
/* Journal file created. */
dbg_journal("journal: file '%s' initialized\n", fn);
return KNOT_EOK;
}