Code review for array_fill patch: fix inadequate check for array size overflow

and bogus documentation (dimension arrays are int[] not anyarray).  Also the
errhint() messages seem to be really errdetail(), since there is nothing
heuristic about them.  Some other trivial cosmetic improvements.

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index fb77ae43ea453f164e515a86ad5b13454d9508d7..15162ed5ed31033d44d1b4201e228c5e4a31c4bc 100644 (file)
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.442 2008/07/18 03:32:51 tgl Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.443 2008/07/21 04:47:00 tgl Exp $ -->
 
  <chapter id="functions">
   <title>Functions and Operators</title>
@@ -9186,17 +9186,16 @@ SELECT NULLIF(value, '(none)') ...
   </sect2>
  </sect1>
 
-
  <sect1 id="functions-array">
   <title>Array Functions and Operators</title>
 
   <para>
    <xref linkend="array-operators-table"> shows the operators
-   available for <type>array</type> types.
+   available for array types.
   </para>
 
     <table id="array-operators-table">
-     <title><type>array</type> Operators</title>
+     <title>Array Operators</title>
      <tgroup cols="4">
       <thead>
        <row>
@@ -9326,7 +9325,7 @@ SELECT NULLIF(value, '(none)') ...
   </para>
 
     <table id="array-functions-table">
-     <title><type>array</type> Functions</title>
+     <title>Array Functions</title>
      <tgroup cols="5">
       <thead>
        <row>
@@ -9374,13 +9373,13 @@ SELECT NULLIF(value, '(none)') ...
        <row>
         <entry>
          <literal>
-          <function>array_fill</function>(<type>anyelement</type>, <type>anyarray</type>,
-          <optional>, <type>anyarray</type></optional>)
+          <function>array_fill</function>(<type>anyelement</type>, <type>int[]</type>,
+          <optional>, <type>int[]</type></optional>)
          </literal>
         </entry>
         <entry><type>anyarray</type></entry>
-        <entry>returns an array initialized with supplied value,
-        dimensions, and lower bounds</entry>
+        <entry>returns an array initialized with supplied value and
+         dimensions, optionally with lower bounds other than 1</entry>
         <entry><literal>array_fill(7, ARRAY[3], ARRAY[2])</literal></entry>
         <entry><literal>[2:4]={7,7,7}</literal></entry>
        </row>

diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index 6c810025e5ef5e1197224d0c25b7abadc8bd105b..5f3356f5600a6a8b13b83c666c54450aedb9e6d6 100644 (file)
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/backend/utils/adt/arrayfuncs.c,v 1.146 2008/07/16 00:48:53 momjian Exp $
+ *       $PostgreSQL: pgsql/src/backend/utils/adt/arrayfuncs.c,v 1.147 2008/07/21 04:47:00 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -97,9 +97,9 @@ static void array_insert_slice(ArrayType *destArray, ArrayType *origArray,
 static int     array_cmp(FunctionCallInfo fcinfo);
 static ArrayType *create_array_envelope(int ndims, int *dimv, int *lbv, int nbytes,
                            Oid elmtype, int dataoffset);
-static ArrayType *array_fill_internal(ArrayType *dims, ArrayType *lbs, Datum value, 
-                                           Oid elmtype, bool isnull, 
-                                           FunctionCallInfo fcinfo);
+static ArrayType *array_fill_internal(ArrayType *dims, ArrayType *lbs,
+                                                                         Datum value, bool isnull, Oid elmtype,
+                                                                         FunctionCallInfo fcinfo);
 
 
 /*
@@ -4245,7 +4245,7 @@ typedef struct generate_subscripts_fctx
         bool    reverse;
 } generate_subscripts_fctx;
 
-/* 
+/*
  * generate_subscripts(array anyarray, dim int [, reverse bool])
  *             Returns all subscripts of the array for any dimension
  */
@@ -4335,7 +4335,7 @@ array_fill_with_lower_bounds(PG_FUNCTION_ARGS)
        bool    isnull;
 
        if (PG_ARGISNULL(1) || PG_ARGISNULL(2))
-               ereport(ERROR, 
+               ereport(ERROR,
                            (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
                             errmsg("dimension array or low bound array cannot be NULL")));
 
@@ -4353,11 +4353,11 @@ array_fill_with_lower_bounds(PG_FUNCTION_ARGS)
                isnull = true;
        }
 
-       elmtype = get_fn_expr_argtype(fcinfo->flinfo, 0); 
-       if (!OidIsValid(elmtype)) 
-               elog(ERROR, "could not determine data type of input"); 
+       elmtype = get_fn_expr_argtype(fcinfo->flinfo, 0);
+       if (!OidIsValid(elmtype))
+               elog(ERROR, "could not determine data type of input");
 
-       result = array_fill_internal(dims, lbs, value, elmtype, isnull, fcinfo);
+       result = array_fill_internal(dims, lbs, value, isnull, elmtype, fcinfo);
        PG_RETURN_ARRAYTYPE_P(result);
 }
 
@@ -4375,7 +4375,7 @@ array_fill(PG_FUNCTION_ARGS)
        bool    isnull;
 
        if (PG_ARGISNULL(1))
-               ereport(ERROR, 
+               ereport(ERROR,
                            (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
                             errmsg("dimension array or low bound array cannot be NULL")));
 
@@ -4392,17 +4392,17 @@ array_fill(PG_FUNCTION_ARGS)
                isnull = true;
        }
 
-       elmtype = get_fn_expr_argtype(fcinfo->flinfo, 0); 
-       if (!OidIsValid(elmtype)) 
-               elog(ERROR, "could not determine data type of input"); 
+       elmtype = get_fn_expr_argtype(fcinfo->flinfo, 0);
+       if (!OidIsValid(elmtype))
+               elog(ERROR, "could not determine data type of input");
 
-       result = array_fill_internal(dims, NULL, value, elmtype, isnull, fcinfo);
+       result = array_fill_internal(dims, NULL, value, isnull, elmtype, fcinfo);
        PG_RETURN_ARRAYTYPE_P(result);
 }
 
 static ArrayType *
 create_array_envelope(int ndims, int *dimv, int *lbsv, int nbytes,
-                           Oid elmtype, int dataoffset)
+                                         Oid elmtype, int dataoffset)
 {
        ArrayType *result;
 
@@ -4418,9 +4418,9 @@ create_array_envelope(int ndims, int *dimv, int *lbsv, int nbytes,
 }
 
 static ArrayType *
-array_fill_internal(ArrayType *dims, ArrayType *lbs, Datum value, 
-                                           Oid elmtype, bool isnull,
-                                           FunctionCallInfo fcinfo)
+array_fill_internal(ArrayType *dims, ArrayType *lbs,
+                                       Datum value, bool isnull, Oid elmtype,
+                                       FunctionCallInfo fcinfo)
 {
        ArrayType       *result;
        int     *dimv;
@@ -4428,34 +4428,34 @@ array_fill_internal(ArrayType *dims, ArrayType *lbs, Datum value,
        int     ndims;
        int     nitems;
        int             deflbs[MAXDIM];
-       int16 elmlen; 
-       bool elmbyval; 
+       int16 elmlen;
+       bool elmbyval;
        char elmalign;
        ArrayMetaState          *my_extra;
 
-       /* 
+       /*
         * Params checks
         */
        if (ARR_NDIM(dims) != 1)
                ereport(ERROR,
                            (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
                             errmsg("wrong number of array subscripts"),
-                            errhint("Dimension array must be one dimensional.")));
+                            errdetail("Dimension array must be one dimensional.")));
 
        if (ARR_LBOUND(dims)[0] != 1)
                ereport(ERROR,
                            (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
                             errmsg("wrong range of array_subscripts"),
-                            errhint("Lower bound of dimension array must be one.")));
-       
+                            errdetail("Lower bound of dimension array must be one.")));
+
        if (ARR_HASNULL(dims))
-               ereport(ERROR, 
+               ereport(ERROR,
                            (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
                             errmsg("dimension values cannot be null")));
 
        dimv = (int *) ARR_DATA_PTR(dims);
        ndims = ARR_DIMS(dims)[0];
-       
+
        if (ndims < 0)                          /* we do allow zero-dimension arrays */
                ereport(ERROR,
                                (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
@@ -4465,23 +4465,23 @@ array_fill_internal(ArrayType *dims, ArrayType *lbs, Datum value,
                                (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
                                 errmsg("number of array dimensions (%d) exceeds the maximum allowed (%d)",
                                                ndims, MAXDIM)));
-       
+
        if (lbs != NULL)
        {
                if (ARR_NDIM(lbs) != 1)
                        ereport(ERROR,
                                    (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
                                     errmsg("wrong number of array subscripts"),
-                                    errhint("Dimension array must be one dimensional.")));
+                                    errdetail("Dimension array must be one dimensional.")));
 
                if (ARR_LBOUND(lbs)[0] != 1)
                        ereport(ERROR,
                                (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
                                 errmsg("wrong range of array_subscripts"),
-                                errhint("Lower bound of dimension array must be one.")));
-       
+                                errdetail("Lower bound of dimension array must be one.")));
+
                if (ARR_HASNULL(lbs))
-                       ereport(ERROR, 
+                       ereport(ERROR,
                                (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
                                 errmsg("dimension values cannot be null")));
 
@@ -4489,14 +4489,14 @@ array_fill_internal(ArrayType *dims, ArrayType *lbs, Datum value,
                        ereport(ERROR,
                                    (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
                                     errmsg("wrong number of array_subscripts"),
-                                    errhint("Low bound array has different size than dimensions array.")));
-                                    
+                                    errdetail("Low bound array has different size than dimensions array.")));
+
                lbsv = (int *) ARR_DATA_PTR(lbs);
        }
-       else    
+       else
        {
                int     i;
-       
+
                for (i = 0; i < MAXDIM; i++)
                        deflbs[i] = 1;
 
@@ -4506,9 +4506,8 @@ array_fill_internal(ArrayType *dims, ArrayType *lbs, Datum value,
        /* fast track for empty array */
        if (ndims == 0)
                return construct_empty_array(elmtype);
-       
-       nitems = ArrayGetNItems(ndims, dimv);
 
+       nitems = ArrayGetNItems(ndims, dimv);
 
        /*
         * We arrange to look up info about element type only once per series of
@@ -4543,7 +4542,7 @@ array_fill_internal(ArrayType *dims, ArrayType *lbs, Datum value,
                int     i;
                char            *p;
                int                     nbytes;
-               Datum   aux_value = value;
+               int                     totbytes;
 
                /* make sure data is not toasted */
                if (elmlen == -1)
@@ -4551,40 +4550,44 @@ array_fill_internal(ArrayType *dims, ArrayType *lbs, Datum value,
 
                nbytes = att_addlength_datum(0, elmlen, value);
                nbytes = att_align_nominal(nbytes, elmalign);
+               Assert(nbytes > 0);
 
-               nbytes *= nitems;
-               /* check for overflow of total request */
-               if (!AllocSizeIsValid(nbytes))
+               totbytes = nbytes * nitems;
+
+               /* check for overflow of multiplication or total request */
+               if (totbytes / nbytes != nitems ||
+                       !AllocSizeIsValid(totbytes))
                        ereport(ERROR,
                                        (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
                                         errmsg("array size exceeds the maximum allowed (%d)",
                                                        (int) MaxAllocSize)));
 
-               nbytes += ARR_OVERHEAD_NONULLS(ndims);
-               result = create_array_envelope(ndims, dimv, lbsv, nbytes,
-                                                       elmtype, 0);
+               /*
+                * This addition can't overflow, but it might cause us to go past
+                * MaxAllocSize.  We leave it to palloc to complain in that case.
+                */
+               totbytes += ARR_OVERHEAD_NONULLS(ndims);
+
+               result = create_array_envelope(ndims, dimv, lbsv, totbytes,
+                                                                          elmtype, 0);
+
                p = ARR_DATA_PTR(result);
                for (i = 0; i < nitems; i++)
                        p += ArrayCastAndSet(value, elmlen, elmbyval, elmalign, p);
-
-               /* cleaning up detoasted copies of datum */
-               if (aux_value != value)
-                       pfree((Pointer) value);
        }
        else
        {
                int     nbytes;
                int     dataoffset;
-               bits8   *bitmap;
 
                dataoffset = ARR_OVERHEAD_WITHNULLS(ndims, nitems);
                nbytes = dataoffset;
 
                result = create_array_envelope(ndims, dimv, lbsv, nbytes,
-                                                       elmtype, dataoffset);
-               bitmap = ARR_NULLBITMAP(result);
-               MemSet(bitmap, 0, (nitems + 7) / 8);
+                                                                          elmtype, dataoffset);
+
+               /* create_array_envelope already zeroed the bitmap, so we're done */
        }
-               
+
        return result;
 }

diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 7b7a01694acecf91bea64887e59803b7a7a481f7..bcb451e8080a9374b33c8cbccd81e6ea9fc82f42 100644 (file)
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -988,6 +988,6 @@ select array_fill(1, array[2,2], null);
 ERROR:  dimension array or low bound array cannot be NULL
 select array_fill(1, array[3,3], array[1,1,1]);
 ERROR:  wrong number of array_subscripts
-HINT:  Low bound array has different size than dimensions array.
+DETAIL:  Low bound array has different size than dimensions array.
 select array_fill(1, array[1,2,null]);
 ERROR:  dimension values cannot be null