/*
* __wt_meta_ckptlist_get --
* Load all available checkpoint information for a file.
*/
int
__wt_meta_ckptlist_get(
WT_SESSION_IMPL *session, const char *fname, WT_CKPT **ckptbasep)
{
WT_CKPT *ckpt, *ckptbase;
WT_CONFIG ckptconf;
WT_CONFIG_ITEM k, v;
WT_DECL_ITEM(buf);
WT_DECL_RET;
size_t allocated, slot;
char *config;
*ckptbasep = NULL;
ckptbase = NULL;
allocated = slot = 0;
config = NULL;
/* Retrieve the metadata information for the file. */
WT_RET(__wt_metadata_search(session, fname, &config));
/* Load any existing checkpoints into the array. */
WT_ERR(__wt_scr_alloc(session, 0, &buf));
if (__wt_config_getones(session, config, "checkpoint", &v) == 0) {
__wt_config_subinit(session, &ckptconf, &v);
for (; __wt_config_next(&ckptconf, &k, &v) == 0; ++slot) {
WT_ERR(__wt_realloc_def(
session, &allocated, slot + 1, &ckptbase));
ckpt = &ckptbase[slot];
WT_ERR(__ckpt_load(session, &k, &v, ckpt));
}
}
/*
* Allocate an extra slot for a new value, plus a slot to mark the end.
*
* This isn't very clean, but there's necessary cooperation between the
* schema layer (that maintains the list of checkpoints), the btree
* layer (that knows when the root page is written, creating a new
* checkpoint), and the block manager (which actually creates the
* checkpoint). All of that cooperation is handled in the WT_CKPT
* structure referenced from the WT_BTREE structure.
*/
WT_ERR(__wt_realloc_def(session, &allocated, slot + 2, &ckptbase));
/* Sort in creation-order. */
qsort(ckptbase, slot, sizeof(WT_CKPT), __ckpt_compare_order);
/* Return the array to our caller. */
*ckptbasep = ckptbase;
if (0) {
err: __wt_meta_ckptlist_free(session, &ckptbase);
}
__wt_free(session, config);
__wt_scr_free(session, &buf);
return (ret);
}
/*
* __wt_salvage --
* Salvage a single file.
*/
int
__wt_salvage(WT_SESSION_IMPL *session, const char *cfg[])
{
WT_CKPT *ckptbase;
WT_DATA_HANDLE *dhandle;
WT_DECL_RET;
dhandle = session->dhandle;
/*
* XXX
* The salvage process reads and discards previous checkpoints, so the
* underlying block manager has to ignore any previous checkpoint
* entries when creating a new checkpoint, in other words, we can't use
* the metadata checkpoint list, it has all of those checkpoint listed
* and we don't care about them. Build a clean checkpoint list and use
* it instead.
*
* Don't first clear the metadata checkpoint list and call the function
* to get a list of checkpoints: a crash between clearing the metadata
* checkpoint list and creating a new checkpoint list would look like a
* create or open of a file without a checkpoint to roll-forward from,
* and the contents of the file would be discarded.
*/
WT_RET(__wt_calloc_def(session, 2, &ckptbase));
WT_ERR(__wt_strdup(session, WT_CHECKPOINT, &ckptbase[0].name));
F_SET(&ckptbase[0], WT_CKPT_ADD);
WT_ERR(__wt_bt_salvage(session, ckptbase, cfg));
/*
* If no checkpoint was created, well, it's probably bad news, but there
* is nothing to do but clear any recorded checkpoints for the file. If
* a checkpoint was created, life is good, replace any existing list of
* checkpoints with the single new one.
*/
if (ckptbase[0].raw.data == NULL)
WT_ERR(__wt_meta_checkpoint_clear(session, dhandle->name));
else
WT_ERR(__wt_meta_ckptlist_set(
session, dhandle->name, ckptbase, NULL));
err: __wt_meta_ckptlist_free(session, &ckptbase);
return (ret);
}
/*
* __wt_meta_ckptlist_get --
* Load all available checkpoint information for a file.
*/
int
__wt_meta_ckptlist_get(
WT_SESSION_IMPL *session, const char *fname, WT_CKPT **ckptbasep)
{
WT_CKPT *ckpt, *ckptbase;
WT_CONFIG ckptconf;
WT_CONFIG_ITEM a, k, v;
WT_DECL_RET;
WT_ITEM *buf;
size_t allocated, slot;
const char *config;
char timebuf[64];
*ckptbasep = NULL;
buf = NULL;
ckptbase = NULL;
allocated = slot = 0;
config = NULL;
/* Retrieve the metadata information for the file. */
WT_RET(__wt_metadata_read(session, fname, &config));
/* Load any existing checkpoints into the array. */
WT_ERR(__wt_scr_alloc(session, 0, &buf));
if (__wt_config_getones(session, config, "checkpoint", &v) == 0 &&
__wt_config_subinit(session, &ckptconf, &v) == 0)
for (; __wt_config_next(&ckptconf, &k, &v) == 0; ++slot) {
if (slot * sizeof(WT_CKPT) == allocated)
WT_ERR(__wt_realloc(session, &allocated,
(slot + 50) * sizeof(WT_CKPT), &ckptbase));
ckpt = &ckptbase[slot];
/*
* Copy the name, address (raw and hex), order and time
* into the slot. If there's no address, it's a fake.
*/
WT_ERR(
__wt_strndup(session, k.str, k.len, &ckpt->name));
WT_ERR(__wt_config_subgets(session, &v, "addr", &a));
WT_ERR(
__wt_buf_set(session, &ckpt->addr, a.str, a.len));
if (a.len == 0)
F_SET(ckpt, WT_CKPT_FAKE);
else
WT_ERR(__wt_nhex_to_raw(
session, a.str, a.len, &ckpt->raw));
WT_ERR(__wt_config_subgets(session, &v, "order", &a));
if (a.val == 0)
goto format;
ckpt->order = a.val;
WT_ERR(__wt_config_subgets(session, &v, "time", &a));
if (a.len == 0)
goto format;
if (a.len > sizeof(timebuf) - 1)
goto format;
memcpy(timebuf, a.str, a.len);
timebuf[a.len] = '\0';
if (sscanf(timebuf, "%" SCNuMAX, &ckpt->sec) != 1)
goto format;
WT_ERR(__wt_config_subgets(session, &v, "size", &a));
ckpt->ckpt_size = (uint64_t)a.val;
}
/*
* Allocate an extra slot for a new value, plus a slot to mark the end.
*
* This isn't very clean, but there's necessary cooperation between the
* schema layer (that maintains the list of checkpoints), the btree
* layer (that knows when the root page is written, creating a new
* checkpoint), and the block manager (which actually creates the
* checkpoint). All of that cooperation is handled in the WT_CKPT
* structure referenced from the WT_BTREE structure.
*/
if ((slot + 2) * sizeof(WT_CKPT) > allocated)
WT_ERR(__wt_realloc(session, &allocated,
(slot + 2) * sizeof(WT_CKPT), &ckptbase));
/* Sort in creation-order. */
qsort(ckptbase, slot, sizeof(WT_CKPT), __ckpt_compare_order);
/* Return the array to our caller. */
*ckptbasep = ckptbase;
if (0) {
format: WT_ERR_MSG(session, WT_ERROR, "corrupted checkpoint list");
err: __wt_meta_ckptlist_free(session, ckptbase);
}
__wt_free(session, config);
__wt_scr_free(&buf);
return (ret);
}
