diff options
| -rw-r--r-- | src/backend/utils/adt/tsvector_op.c | 36 |
1 files changed, 30 insertions, 6 deletions
diff --git a/src/backend/utils/adt/tsvector_op.c b/src/backend/utils/adt/tsvector_op.c index 94c242d9638..df6fcd6ad3f 100644 --- a/src/backend/utils/adt/tsvector_op.c +++ b/src/backend/utils/adt/tsvector_op.c @@ -340,11 +340,14 @@ tsvector_concat(PG_FUNCTION_ARGS) j, i1, i2, - dataoff; + dataoff, + output_bytes, + output_size; char *data, *data1, *data2; + /* Get max position in in1; we'll need this to offset in2's positions */ ptr = ARRPTR(in1); i = in1->size; while (i--) @@ -368,10 +371,23 @@ tsvector_concat(PG_FUNCTION_ARGS) data2 = STRPTR(in2); i1 = in1->size; i2 = in2->size; - /* conservative estimate of space needed */ - out = (TSVector) palloc0(VARSIZE(in1) + VARSIZE(in2)); - SET_VARSIZE(out, VARSIZE(in1) + VARSIZE(in2)); + + /* + * Conservative estimate of space needed. We might need all the data + * in both inputs, and conceivably add a pad byte before position data + * for each item where there was none before. + */ + output_bytes = VARSIZE(in1) + VARSIZE(in2) + i1 + i2; + + out = (TSVector) palloc0(output_bytes); + SET_VARSIZE(out, output_bytes); + + /* + * We must make out->size valid so that STRPTR(out) is sensible. We'll + * collapse out any unused space at the end. + */ out->size = in1->size + in2->size; + ptr = ARRPTR(out); data = STRPTR(out); dataoff = 0; @@ -513,10 +529,18 @@ tsvector_concat(PG_FUNCTION_ARGS) (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED), errmsg("string is too long for tsvector (%d bytes, max %d bytes)", dataoff, MAXSTRPOS))); - out->size = ptr - ARRPTR(out); - SET_VARSIZE(out, CALCDATASIZE(out->size, dataoff)); + /* + * Adjust sizes (asserting that we didn't overrun the original estimates) + * and collapse out any unused array entries. + */ + output_size = ptr - ARRPTR(out); + Assert(output_size <= out->size); + out->size = output_size; if (data != STRPTR(out)) memmove(STRPTR(out), data, dataoff); + output_bytes = CALCDATASIZE(out->size, dataoff); + Assert(output_bytes <= VARSIZE(out)); + SET_VARSIZE(out, output_bytes); PG_FREE_IF_COPY(in1, 0); PG_FREE_IF_COPY(in2, 1); |