Fix ts_delete(tsvector, text[]) to cope with duplicate array entries.

Such cases either failed an Assert, or produced a corrupt tsvector in
non-Assert builds, as reported by Andreas Seltenreich.  The reason is
that tsvector_delete_by_indices() just assumed that its input array had
no duplicates.  Fix by explicitly de-duping.

In passing, improve some comments, and fix a number of tests for null
values to use ERRCODE_NULL_VALUE_NOT_ALLOWED not
ERRCODE_INVALID_PARAMETER_VALUE.

Discussion: <[email protected]>

diff --git a/src/backend/utils/adt/tsvector_op.c b/src/backend/utils/adt/tsvector_op.c
index 63ae4330ef1fbf2c12cd5a998bb91dfdfee6d5aa..29cc687643c1746d5a8b270ee1cbaa3ca548ae67 100644 (file)
--- a/src/backend/utils/adt/tsvector_op.c
+++ b/src/backend/utils/adt/tsvector_op.c
@@ -317,7 +317,7 @@ tsvector_setweight_by_filter(PG_FUNCTION_ARGS)
 
        if (nulls[i])
            ereport(ERROR,
-                   (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+                   (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
                     errmsg("lexeme array may not contain nulls")));
 
        lex = VARDATA(dlexemes[i]);
@@ -430,7 +430,7 @@ compareint(const void *va, const void *vb)
 /*
  * Internal routine to delete lexemes from TSVector by array of offsets.
  *
- * int *indices_to_delete -- array of lexeme offsets to delete
+ * int *indices_to_delete -- array of lexeme offsets to delete (modified here!)
  * int indices_count -- size of that array
  *
  * Returns new TSVector without given lexemes along with their positions
@@ -445,35 +445,51 @@ tsvector_delete_by_indices(TSVector tsv, int *indices_to_delete,
               *arrout;
    char       *data = STRPTR(tsv),
               *dataout;
-   int         i,
-               j,
-               k,
-               curoff;
+   int         i,              /* index in arrin */
+               j,              /* index in arrout */
+               k,              /* index in indices_to_delete */
+               curoff;         /* index in dataout area */
 
    /*
-    * Here we overestimates tsout size, since we don't know exact size
-    * occupied by positions and weights. We will set exact size later after a
-    * pass through TSVector.
+    * Sort the filter array to simplify membership checks below.  Also, get
+    * rid of any duplicate entries, so that we can assume that indices_count
+    * is exactly equal to the number of lexemes that will be removed.
     */
-   tsout = (TSVector) palloc0(VARSIZE(tsv));
-   arrout = ARRPTR(tsout);
-   tsout->size = tsv->size - indices_count;
-
-   /* Sort our filter array to simplify membership check later. */
    if (indices_count > 1)
+   {
+       int         kp;
+
        qsort(indices_to_delete, indices_count, sizeof(int), compareint);
+       kp = 0;
+       for (k = 1; k < indices_count; k++)
+       {
+           if (indices_to_delete[k] != indices_to_delete[kp])
+               indices_to_delete[++kp] = indices_to_delete[k];
+       }
+       indices_count = ++kp;
+   }
 
    /*
-    * Copy tsv to tsout skipping lexemes that enlisted in indices_to_delete.
+    * Here we overestimate tsout size, since we don't know how much space is
+    * used by the deleted lexeme(s).  We will set exact size below.
     */
-   curoff = 0;
+   tsout = (TSVector) palloc0(VARSIZE(tsv));
+
+   /* This count must be correct because STRPTR(tsout) relies on it. */
+   tsout->size = tsv->size - indices_count;
+
+   /*
+    * Copy tsv to tsout, skipping lexemes listed in indices_to_delete.
+    */
+   arrout = ARRPTR(tsout);
    dataout = STRPTR(tsout);
+   curoff = 0;
    for (i = j = k = 0; i < tsv->size; i++)
    {
        /*
-        * Here we should check whether current i is present in
-        * indices_to_delete or not. Since indices_to_delete is already sorted
-        * we can advance it index only when we have match.
+        * If current i is present in indices_to_delete, skip this lexeme.
+        * Since indices_to_delete is already sorted, we only need to check
+        * the current (k'th) entry.
         */
        if (k < indices_count && i == indices_to_delete[k])
        {
@@ -481,7 +497,7 @@ tsvector_delete_by_indices(TSVector tsv, int *indices_to_delete,
            continue;
        }
 
-       /* Copy lexeme, it's positions and weights */
+       /* Copy lexeme and its positions and weights */
        memcpy(dataout + curoff, data + arrin[i].pos, arrin[i].len);
        arrout[j].haspos = arrin[i].haspos;
        arrout[j].len = arrin[i].len;
@@ -489,8 +505,8 @@ tsvector_delete_by_indices(TSVector tsv, int *indices_to_delete,
        curoff += arrin[i].len;
        if (arrin[i].haspos)
        {
-           int         len = POSDATALEN(tsv, arrin + i) * sizeof(WordEntryPos) +
-           sizeof(uint16);
+           int         len = POSDATALEN(tsv, arrin + i) * sizeof(WordEntryPos)
+           + sizeof(uint16);
 
            curoff = SHORTALIGN(curoff);
            memcpy(dataout + curoff,
@@ -503,10 +519,9 @@ tsvector_delete_by_indices(TSVector tsv, int *indices_to_delete,
    }
 
    /*
-    * After the pass through TSVector k should equals exactly to
-    * indices_count. If it isn't then the caller provided us with indices
-    * outside of [0, tsv->size) range and estimation of tsout's size is
-    * wrong.
+    * k should now be exactly equal to indices_count. If it isn't then the
+    * caller provided us with indices outside of [0, tsv->size) range and
+    * estimation of tsout's size is wrong.
     */
    Assert(k == indices_count);
 
@@ -560,7 +575,7 @@ tsvector_delete_arr(PG_FUNCTION_ARGS)
 
    /*
     * In typical use case array of lexemes to delete is relatively small. So
-    * here we optimizing things for that scenario: iterate through lexarr
+    * here we optimize things for that scenario: iterate through lexarr
     * performing binary search of each lexeme from lexarr in tsvector.
     */
    skip_indices = palloc0(nlex * sizeof(int));
@@ -572,10 +587,10 @@ tsvector_delete_arr(PG_FUNCTION_ARGS)
 
        if (nulls[i])
            ereport(ERROR,
-                   (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+                   (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
                     errmsg("lexeme array may not contain nulls")));
 
-       lex = VARDATA(dlexemes[i]);
+       lex = VARDATA_ANY(dlexemes[i]);
        lex_len = VARSIZE_ANY_EXHDR(dlexemes[i]);
        lex_pos = tsvector_bsearch(tsin, lex, lex_len);
 
@@ -738,7 +753,7 @@ array_to_tsvector(PG_FUNCTION_ARGS)
    {
        if (nulls[i])
            ereport(ERROR,
-                   (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+                   (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
                     errmsg("lexeme array may not contain nulls")));
 
        datalen += VARSIZE_ANY_EXHDR(dlexemes[i]);
@@ -797,7 +812,7 @@ tsvector_filter(PG_FUNCTION_ARGS)
 
        if (nulls[i])
            ereport(ERROR,
-                   (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+                   (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
                     errmsg("weight array may not contain nulls")));
 
        char_weight = DatumGetChar(dweights[i]);

diff --git a/src/test/regress/expected/tstypes.out b/src/test/regress/expected/tstypes.out
index 886ea747f17733f6b38e15bbd48bbf43b55fa316..73f43c5ff027364d1b8ed7ad093245f2ba32147c 100644 (file)
--- a/src/test/regress/expected/tstypes.out
+++ b/src/test/regress/expected/tstypes.out
@@ -1087,6 +1087,12 @@ SELECT ts_delete('base hidden rebel spaceship strike'::tsvector, ARRAY['spaceshi
  'base' 'hidden' 'strike'
 (1 row)
 
+SELECT ts_delete('base hidden rebel spaceship strike'::tsvector, ARRAY['spaceship','leya','rebel','rebel']);
+        ts_delete         
+--------------------------
+ 'base' 'hidden' 'strike'
+(1 row)
+
 SELECT ts_delete('base hidden rebel spaceship strike'::tsvector, ARRAY['spaceship','leya','rebel', NULL]);
 ERROR:  lexeme array may not contain nulls
 SELECT unnest('base:7 hidden:6 rebel:1 spaceship:2,33A,34B,35C,36D strike:3'::tsvector);

diff --git a/src/test/regress/sql/tstypes.sql b/src/test/regress/sql/tstypes.sql
index 724234d94d25daae8dc7708f2c010791696579c1..f0c06ba5f5a6e1c37ca51521bb5ad7690579da11 100644 (file)
--- a/src/test/regress/sql/tstypes.sql
+++ b/src/test/regress/sql/tstypes.sql
@@ -212,6 +212,7 @@ SELECT ts_delete('base:7 hidden:6 rebel:1 spaceship:2,33A,34B,35C,36D strike:3':
 SELECT ts_delete('base:7 hidden:6 rebel:1 spaceship:2,33A,34B,35C,36D strike:3'::tsvector, ARRAY['spaceshi','rebel']);
 SELECT ts_delete('base:7 hidden:6 rebel:1 spaceship:2,33A,34B,35C,36D strike:3'::tsvector, ARRAY['spaceship','leya','rebel']);
 SELECT ts_delete('base hidden rebel spaceship strike'::tsvector, ARRAY['spaceship','leya','rebel']);
+SELECT ts_delete('base hidden rebel spaceship strike'::tsvector, ARRAY['spaceship','leya','rebel','rebel']);
 SELECT ts_delete('base hidden rebel spaceship strike'::tsvector, ARRAY['spaceship','leya','rebel', NULL]);
 
 SELECT unnest('base:7 hidden:6 rebel:1 spaceship:2,33A,34B,35C,36D strike:3'::tsvector);