#endif
#endif
-long int rra_random_row(
- rra_def_t *);
-
-
/* Open a database file, return its header and an open filehandle,
* positioned to the first cdp in the first rra.
* In the error path of rrd_open, only rrd_free(&rrd) has to be called
* before returning an error. Do not call rrd_close upon failure of rrd_open.
+ * If creating a new file, the parameter rrd must be initialised with
+ * details of the file content.
+ * If opening an existing file, then use rrd must be initialised by
+ * rrd_init(rrd) prior to invoking rrd_open
*/
rrd_file_t *rrd_open(
rrd_t *rrd,
unsigned rdwr)
{
+ int i;
int flags = 0;
mode_t mode = S_IRUSR;
int version;
#ifdef HAVE_MMAP
ssize_t _page_size = sysconf(_SC_PAGESIZE);
- int mm_prot = PROT_READ, mm_flags = 0;
char *data = MAP_FAILED;
#endif
off_t offset = 0;
struct stat statb;
rrd_file_t *rrd_file = NULL;
off_t newfile_size = 0;
+ off_t header_len, value_cnt, data_len;
- if ((rdwr & RRD_CREAT) && (rdwr & RRD_CREAT_SETSIZE)) {
- /* yes bad inline signaling alert, we are using the
- floatcookie to pass the size in ... only used in resize */
- newfile_size = (off_t) rrd->stat_head->float_cookie;
- free(rrd->stat_head);
+ /* Are we creating a new file? */
+ if((rdwr & RRD_CREAT) && (rrd->stat_head != NULL))
+ {
+ header_len = \
+ sizeof(stat_head_t) + \
+ sizeof(ds_def_t) * rrd->stat_head->ds_cnt + \
+ sizeof(rra_def_t) * rrd->stat_head->rra_cnt + \
+ sizeof(time_t) + \
+ sizeof(live_head_t) + \
+ sizeof(pdp_prep_t) * rrd->stat_head->ds_cnt + \
+ sizeof(cdp_prep_t) * rrd->stat_head->ds_cnt * rrd->stat_head->rra_cnt + \
+ sizeof(rra_ptr_t) * rrd->stat_head->rra_cnt;
+
+ value_cnt = 0;
+ for (i = 0; i < rrd->stat_head->rra_cnt; i++)
+ value_cnt += rrd->stat_head->ds_cnt * rrd->rra_def[i].row_cnt;
+
+ data_len = sizeof(rrd_value_t) * value_cnt;
+
+ newfile_size = header_len + data_len;
}
- if(!(rdwr & RRD_CREAT))
- rrd_init(rrd);
+
rrd_file = malloc(sizeof(rrd_file_t));
if (rrd_file == NULL) {
rrd_set_error("allocating rrd_file descriptor for '%s'", file_name);
exit(-1);
}
#endif
+
+#ifdef HAVE_MMAP
+ rrd_file->mm_prot = PROT_READ;
+ rrd_file->mm_flags = 0;
+#endif
+
if (rdwr & RRD_READONLY) {
flags |= O_RDONLY;
#ifdef HAVE_MMAP
- mm_flags = MAP_PRIVATE;
+ rrd_file->mm_flags = MAP_PRIVATE;
# ifdef MAP_NORESERVE
- mm_flags |= MAP_NORESERVE; /* readonly, so no swap backing needed */
+ rrd_file->mm_flags |= MAP_NORESERVE; /* readonly, so no swap backing needed */
# endif
#endif
} else {
mode |= S_IWUSR;
flags |= O_RDWR;
#ifdef HAVE_MMAP
- mm_flags = MAP_SHARED;
- mm_prot |= PROT_WRITE;
+ rrd_file->mm_flags = MAP_SHARED;
+ rrd_file->mm_prot |= PROT_WRITE;
#endif
}
if (rdwr & RRD_CREAT) {
}
if (rdwr & RRD_READAHEAD) {
#ifdef MAP_POPULATE
- mm_flags |= MAP_POPULATE; /* populate ptes and data */
+ rrd_file->mm_flags |= MAP_POPULATE; /* populate ptes and data */
#endif
#if defined MAP_NONBLOCK
- mm_flags |= MAP_NONBLOCK; /* just populate ptes */
+ rrd_file->mm_flags |= MAP_NONBLOCK; /* just populate ptes */
#endif
}
#if defined(_WIN32) && !defined(__CYGWIN__) && !defined(__CYGWIN32__)
*/
#ifdef HAVE_MMAP
- if(rrd_file->file_len == 0 && (rdwr & RRD_CREAT))
- {
- rrd_file->file_start = NULL;
- goto out_done;
- }
- data = mmap(0, rrd_file->file_len, mm_prot, mm_flags,
+ data = mmap(0, rrd_file->file_len, rrd_file->mm_prot, rrd_file->mm_flags,
rrd_file->fd, offset);
/* lets see if the first read worked */
}
#endif /* defined DEBUG && DEBUG > 1 */
+/*
+ * get exclusive lock to whole file.
+ * lock gets removed when we close the file
+ *
+ * returns 0 on success
+ */
+int rrd_lock(
+ rrd_file_t *file)
+{
+ int rcstat;
+
+ {
+#if defined(_WIN32) && !defined(__CYGWIN__) && !defined(__CYGWIN32__)
+ struct _stat st;
+
+ if (_fstat(file->fd, &st) == 0) {
+ rcstat = _locking(file->fd, _LK_NBLCK, st.st_size);
+ } else {
+ rcstat = -1;
+ }
+#else
+ struct flock lock;
+
+ lock.l_type = F_WRLCK; /* exclusive write lock */
+ lock.l_len = 0; /* whole file */
+ lock.l_start = 0; /* start of file */
+ lock.l_whence = SEEK_SET; /* end of file */
+
+ rcstat = fcntl(file->fd, F_SETLK, &lock);
+#endif
+ }
+
+ return (rcstat);
+}
+
/* drop cache except for the header and the active pages */
void rrd_dontneed(
size_t count)
{
#ifdef HAVE_MMAP
- /* These flags are used if creating a new RRD */
- int mm_prot = PROT_READ | PROT_WRITE, mm_flags = MAP_SHARED;
int old_size = rrd_file->file_len;
- int new_size = rrd_file->file_len;
if (count == 0)
return 0;
if (buf == NULL)
if((rrd_file->pos + count) > old_size)
{
- new_size = rrd_file->pos + count;
- rrd_file->file_len = new_size;
- lseek(rrd_file->fd, new_size - 1, SEEK_SET);
- write(rrd_file->fd, "\0", 1); /* poke */
- lseek(rrd_file->fd, 0, SEEK_SET);
- if(rrd_file->file_start == NULL)
- {
- rrd_file->file_start = mmap(0, new_size, mm_prot, mm_flags,
- rrd_file->fd, 0);
- }
- else
- rrd_file->file_start = mremap(rrd_file->file_start, old_size, new_size, MREMAP_MAYMOVE);
-
- if (rrd_file->file_start == MAP_FAILED) {
- rrd_set_error("m(re)maping file : %s",
- rrd_strerror(errno));
- return -1;
- }
+ rrd_set_error("attempting to write beyond end of file");
+ return -1;
}
memcpy(rrd_file->file_start + rrd_file->pos, buf, count);
rrd_file->pos += count;
{
free(mem);
}
-
-/*
- * rra_update informs us about the RRAs being updated
- * The low level storage API may use this information for
- * aligning RRAs within stripes, or other performance enhancements
- */
-void rrd_notify_row(
- rrd_file_t *rrd_file,
- int rra_idx,
- unsigned long rra_row,
- time_t rra_time)
-{
-}
-
-/*
- * This function is called when creating a new RRD
- * The storage implementation can use this opportunity to select
- * a sensible starting row within the file.
- * The default implementation is random, to ensure that all RRAs
- * don't change to a new disk block at the same time
- */
-unsigned long rrd_select_initial_row(
- rrd_file_t *rrd_file,
- int rra_idx,
- rra_def_t *rra
- )
-{
- return rra_random_row(rra);
-}
-
-static int rand_init = 0;
-
-long int rra_random_row(
- rra_def_t *rra)
-{
- if (!rand_init) {
- srandom((unsigned int) time(NULL) + (unsigned int) getpid());
- rand_init++;
- }
-
- return random() % rra->row_cnt;
-}
-
projects / rrdtool.git / blobdiff