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-rw-r--r--src/backend/access/common/detoast.c220
1 files changed, 102 insertions, 118 deletions
diff --git a/src/backend/access/common/detoast.c b/src/backend/access/common/detoast.c
index 8c89fc2a558..61d7e64c449 100644
--- a/src/backend/access/common/detoast.c
+++ b/src/backend/access/common/detoast.c
@@ -25,7 +25,8 @@
static struct varlena *toast_fetch_datum(struct varlena *attr);
static struct varlena *toast_fetch_datum_slice(struct varlena *attr,
- int32 sliceoffset, int32 length);
+ int32 sliceoffset,
+ int32 slicelength);
static struct varlena *toast_decompress_datum(struct varlena *attr);
static struct varlena *toast_decompress_datum_slice(struct varlena *attr, int32 slicelength);
@@ -331,14 +332,9 @@ toast_fetch_datum(struct varlena *attr)
TupleDesc toasttupDesc;
struct varlena *result;
struct varatt_external toast_pointer;
- int32 ressize;
- int32 residx,
- nextidx;
- int32 numchunks;
- Pointer chunk;
- bool isnull;
- char *chunkdata;
- int32 chunksize;
+ int32 attrsize;
+ int32 expectedchunk;
+ int32 totalchunks;
int num_indexes;
int validIndex;
SnapshotData SnapshotToast;
@@ -349,15 +345,15 @@ toast_fetch_datum(struct varlena *attr)
/* Must copy to access aligned fields */
VARATT_EXTERNAL_GET_POINTER(toast_pointer, attr);
- ressize = toast_pointer.va_extsize;
- numchunks = ((ressize - 1) / TOAST_MAX_CHUNK_SIZE) + 1;
+ attrsize = toast_pointer.va_extsize;
+ totalchunks = ((attrsize - 1) / TOAST_MAX_CHUNK_SIZE) + 1;
- result = (struct varlena *) palloc(ressize + VARHDRSZ);
+ result = (struct varlena *) palloc(attrsize + VARHDRSZ);
if (VARATT_EXTERNAL_IS_COMPRESSED(toast_pointer))
- SET_VARSIZE_COMPRESSED(result, ressize + VARHDRSZ);
+ SET_VARSIZE_COMPRESSED(result, attrsize + VARHDRSZ);
else
- SET_VARSIZE(result, ressize + VARHDRSZ);
+ SET_VARSIZE(result, attrsize + VARHDRSZ);
/*
* Open the toast relation and its indexes
@@ -386,17 +382,24 @@ toast_fetch_datum(struct varlena *attr)
* see the chunks in chunkidx order, even though we didn't explicitly ask
* for it.
*/
- nextidx = 0;
+ expectedchunk = 0;
init_toast_snapshot(&SnapshotToast);
toastscan = systable_beginscan_ordered(toastrel, toastidxs[validIndex],
&SnapshotToast, 1, &toastkey);
while ((ttup = systable_getnext_ordered(toastscan, ForwardScanDirection)) != NULL)
{
+ int32 curchunk;
+ Pointer chunk;
+ bool isnull;
+ char *chunkdata;
+ int32 chunksize;
+ int32 expected_size;
+
/*
* Have a chunk, extract the sequence number and the data
*/
- residx = DatumGetInt32(fastgetattr(ttup, 2, toasttupDesc, &isnull));
+ curchunk = DatumGetInt32(fastgetattr(ttup, 2, toasttupDesc, &isnull));
Assert(!isnull);
chunk = DatumGetPointer(fastgetattr(ttup, 3, toasttupDesc, &isnull));
Assert(!isnull);
@@ -424,63 +427,50 @@ toast_fetch_datum(struct varlena *attr)
/*
* Some checks on the data we've found
*/
- if (residx != nextidx)
+ if (curchunk != expectedchunk)
ereport(ERROR,
(errcode(ERRCODE_DATA_CORRUPTED),
errmsg_internal("unexpected chunk number %d (expected %d) for toast value %u in %s",
- residx, nextidx,
+ curchunk, expectedchunk,
toast_pointer.va_valueid,
RelationGetRelationName(toastrel))));
- if (residx < numchunks - 1)
- {
- if (chunksize != TOAST_MAX_CHUNK_SIZE)
- ereport(ERROR,
- (errcode(ERRCODE_DATA_CORRUPTED),
- errmsg_internal("unexpected chunk size %d (expected %d) in chunk %d of %d for toast value %u in %s",
- chunksize, (int) TOAST_MAX_CHUNK_SIZE,
- residx, numchunks,
- toast_pointer.va_valueid,
- RelationGetRelationName(toastrel))));
- }
- else if (residx == numchunks - 1)
- {
- if ((residx * TOAST_MAX_CHUNK_SIZE + chunksize) != ressize)
- ereport(ERROR,
- (errcode(ERRCODE_DATA_CORRUPTED),
- errmsg_internal("unexpected chunk size %d (expected %d) in final chunk %d for toast value %u in %s",
- chunksize,
- (int) (ressize - residx * TOAST_MAX_CHUNK_SIZE),
- residx,
- toast_pointer.va_valueid,
- RelationGetRelationName(toastrel))));
- }
- else
+ if (curchunk > totalchunks - 1)
ereport(ERROR,
(errcode(ERRCODE_DATA_CORRUPTED),
errmsg_internal("unexpected chunk number %d (out of range %d..%d) for toast value %u in %s",
- residx,
- 0, numchunks - 1,
+ curchunk,
+ 0, totalchunks - 1,
+ toast_pointer.va_valueid,
+ RelationGetRelationName(toastrel))));
+ expected_size = curchunk < totalchunks - 1 ? TOAST_MAX_CHUNK_SIZE
+ : attrsize % TOAST_MAX_CHUNK_SIZE;
+ if (chunksize != expected_size)
+ ereport(ERROR,
+ (errcode(ERRCODE_DATA_CORRUPTED),
+ errmsg_internal("unexpected chunk size %d (expected %d) in chunk %d of %d for toast value %u in %s",
+ chunksize, expected_size,
+ curchunk, totalchunks,
toast_pointer.va_valueid,
RelationGetRelationName(toastrel))));
/*
* Copy the data into proper place in our result
*/
- memcpy(VARDATA(result) + residx * TOAST_MAX_CHUNK_SIZE,
+ memcpy(VARDATA(result) + curchunk * TOAST_MAX_CHUNK_SIZE,
chunkdata,
chunksize);
- nextidx++;
+ expectedchunk++;
}
/*
* Final checks that we successfully fetched the datum
*/
- if (nextidx != numchunks)
+ if (expectedchunk != totalchunks)
ereport(ERROR,
(errcode(ERRCODE_DATA_CORRUPTED),
errmsg_internal("missing chunk number %d for toast value %u in %s",
- nextidx,
+ expectedchunk,
toast_pointer.va_valueid,
RelationGetRelationName(toastrel))));
@@ -506,7 +496,8 @@ toast_fetch_datum(struct varlena *attr)
* ----------
*/
static struct varlena *
-toast_fetch_datum_slice(struct varlena *attr, int32 sliceoffset, int32 length)
+toast_fetch_datum_slice(struct varlena *attr, int32 sliceoffset,
+ int32 slicelength)
{
Relation toastrel;
Relation *toastidxs;
@@ -518,20 +509,10 @@ toast_fetch_datum_slice(struct varlena *attr, int32 sliceoffset, int32 length)
struct varlena *result;
struct varatt_external toast_pointer;
int32 attrsize;
- int32 residx;
- int32 nextidx;
- int numchunks;
+ int32 expectedchunk;
int startchunk;
int endchunk;
- int32 startoffset;
- int32 endoffset;
int totalchunks;
- Pointer chunk;
- bool isnull;
- char *chunkdata;
- int32 chunksize;
- int32 chcpystrt;
- int32 chcpyend;
int num_indexes;
int validIndex;
SnapshotData SnapshotToast;
@@ -555,7 +536,7 @@ toast_fetch_datum_slice(struct varlena *attr, int32 sliceoffset, int32 length)
if (sliceoffset >= attrsize)
{
sliceoffset = 0;
- length = 0;
+ slicelength = 0;
}
/*
@@ -563,28 +544,25 @@ toast_fetch_datum_slice(struct varlena *attr, int32 sliceoffset, int32 length)
* rawsize tracking amount of raw data, which is stored at the beginning
* as an int32 value).
*/
- if (VARATT_EXTERNAL_IS_COMPRESSED(toast_pointer) && length > 0)
- length = length + sizeof(int32);
+ if (VARATT_EXTERNAL_IS_COMPRESSED(toast_pointer) && slicelength > 0)
+ slicelength = slicelength + sizeof(int32);
- if (((sliceoffset + length) > attrsize) || length < 0)
- length = attrsize - sliceoffset;
+ if (((sliceoffset + slicelength) > attrsize) || slicelength < 0)
+ slicelength = attrsize - sliceoffset;
- result = (struct varlena *) palloc(length + VARHDRSZ);
+ result = (struct varlena *) palloc(slicelength + VARHDRSZ);
if (VARATT_EXTERNAL_IS_COMPRESSED(toast_pointer))
- SET_VARSIZE_COMPRESSED(result, length + VARHDRSZ);
+ SET_VARSIZE_COMPRESSED(result, slicelength + VARHDRSZ);
else
- SET_VARSIZE(result, length + VARHDRSZ);
+ SET_VARSIZE(result, slicelength + VARHDRSZ);
- if (length == 0)
+ if (slicelength == 0)
return result; /* Can save a lot of work at this point! */
startchunk = sliceoffset / TOAST_MAX_CHUNK_SIZE;
- endchunk = (sliceoffset + length - 1) / TOAST_MAX_CHUNK_SIZE;
- numchunks = (endchunk - startchunk) + 1;
-
- startoffset = sliceoffset % TOAST_MAX_CHUNK_SIZE;
- endoffset = (sliceoffset + length - 1) % TOAST_MAX_CHUNK_SIZE;
+ endchunk = (sliceoffset + slicelength - 1) / TOAST_MAX_CHUNK_SIZE;
+ Assert(endchunk < totalchunks);
/*
* Open the toast relation and its indexes
@@ -610,7 +588,7 @@ toast_fetch_datum_slice(struct varlena *attr, int32 sliceoffset, int32 length)
/*
* Use equality condition for one chunk, a range condition otherwise:
*/
- if (numchunks == 1)
+ if (startchunk == endchunk)
{
ScanKeyInit(&toastkey[1],
(AttrNumber) 2,
@@ -637,15 +615,24 @@ toast_fetch_datum_slice(struct varlena *attr, int32 sliceoffset, int32 length)
* The index is on (valueid, chunkidx) so they will come in order
*/
init_toast_snapshot(&SnapshotToast);
- nextidx = startchunk;
+ expectedchunk = startchunk;
toastscan = systable_beginscan_ordered(toastrel, toastidxs[validIndex],
&SnapshotToast, nscankeys, toastkey);
while ((ttup = systable_getnext_ordered(toastscan, ForwardScanDirection)) != NULL)
{
+ int32 curchunk;
+ Pointer chunk;
+ bool isnull;
+ char *chunkdata;
+ int32 chunksize;
+ int32 expected_size;
+ int32 chcpystrt;
+ int32 chcpyend;
+
/*
* Have a chunk, extract the sequence number and the data
*/
- residx = DatumGetInt32(fastgetattr(ttup, 2, toasttupDesc, &isnull));
+ curchunk = DatumGetInt32(fastgetattr(ttup, 2, toasttupDesc, &isnull));
Assert(!isnull);
chunk = DatumGetPointer(fastgetattr(ttup, 3, toasttupDesc, &isnull));
Assert(!isnull);
@@ -673,63 +660,60 @@ toast_fetch_datum_slice(struct varlena *attr, int32 sliceoffset, int32 length)
/*
* Some checks on the data we've found
*/
- if ((residx != nextidx) || (residx > endchunk) || (residx < startchunk))
- elog(ERROR, "unexpected chunk number %d (expected %d) for toast value %u in %s",
- residx, nextidx,
- toast_pointer.va_valueid,
- RelationGetRelationName(toastrel));
- if (residx < totalchunks - 1)
- {
- if (chunksize != TOAST_MAX_CHUNK_SIZE)
- elog(ERROR, "unexpected chunk size %d (expected %d) in chunk %d of %d for toast value %u in %s when fetching slice",
- chunksize, (int) TOAST_MAX_CHUNK_SIZE,
- residx, totalchunks,
- toast_pointer.va_valueid,
- RelationGetRelationName(toastrel));
- }
- else if (residx == totalchunks - 1)
- {
- if ((residx * TOAST_MAX_CHUNK_SIZE + chunksize) != attrsize)
- elog(ERROR, "unexpected chunk size %d (expected %d) in final chunk %d for toast value %u in %s when fetching slice",
- chunksize,
- (int) (attrsize - residx * TOAST_MAX_CHUNK_SIZE),
- residx,
- toast_pointer.va_valueid,
- RelationGetRelationName(toastrel));
- }
- else
- elog(ERROR, "unexpected chunk number %d (out of range %d..%d) for toast value %u in %s",
- residx,
- 0, totalchunks - 1,
- toast_pointer.va_valueid,
- RelationGetRelationName(toastrel));
+ if (curchunk != expectedchunk)
+ ereport(ERROR,
+ (errcode(ERRCODE_DATA_CORRUPTED),
+ errmsg_internal("unexpected chunk number %d (expected %d) for toast value %u in %s",
+ curchunk, expectedchunk,
+ toast_pointer.va_valueid,
+ RelationGetRelationName(toastrel))));
+ if (curchunk > endchunk)
+ ereport(ERROR,
+ (errcode(ERRCODE_DATA_CORRUPTED),
+ errmsg_internal("unexpected chunk number %d (out of range %d..%d) for toast value %u in %s",
+ curchunk,
+ startchunk, endchunk,
+ toast_pointer.va_valueid,
+ RelationGetRelationName(toastrel))));
+ expected_size = curchunk < totalchunks - 1 ? TOAST_MAX_CHUNK_SIZE
+ : attrsize % TOAST_MAX_CHUNK_SIZE;
+ if (chunksize != expected_size)
+ ereport(ERROR,
+ (errcode(ERRCODE_DATA_CORRUPTED),
+ errmsg_internal("unexpected chunk size %d (expected %d) in chunk %d of %d for toast value %u in %s",
+ chunksize, expected_size,
+ curchunk, totalchunks,
+ toast_pointer.va_valueid,
+ RelationGetRelationName(toastrel))));
/*
* Copy the data into proper place in our result
*/
chcpystrt = 0;
chcpyend = chunksize - 1;
- if (residx == startchunk)
- chcpystrt = startoffset;
- if (residx == endchunk)
- chcpyend = endoffset;
+ if (curchunk == startchunk)
+ chcpystrt = sliceoffset % TOAST_MAX_CHUNK_SIZE;
+ if (curchunk == endchunk)
+ chcpyend = (sliceoffset + slicelength - 1) % TOAST_MAX_CHUNK_SIZE;
memcpy(VARDATA(result) +
- (residx * TOAST_MAX_CHUNK_SIZE - sliceoffset) + chcpystrt,
+ (curchunk * TOAST_MAX_CHUNK_SIZE - sliceoffset) + chcpystrt,
chunkdata + chcpystrt,
(chcpyend - chcpystrt) + 1);
- nextidx++;
+ expectedchunk++;
}
/*
* Final checks that we successfully fetched the datum
*/
- if (nextidx != (endchunk + 1))
- elog(ERROR, "missing chunk number %d for toast value %u in %s",
- nextidx,
- toast_pointer.va_valueid,
- RelationGetRelationName(toastrel));
+ if (expectedchunk != (endchunk + 1))
+ ereport(ERROR,
+ (errcode(ERRCODE_DATA_CORRUPTED),
+ errmsg_internal("missing chunk number %d for toast value %u in %s",
+ expectedchunk,
+ toast_pointer.va_valueid,
+ RelationGetRelationName(toastrel))));
/*
* End scan and close relations
generated by cgit v1.2.3 (git 2.25.1) at 2025-06-01 11:33:34 +0000