diff options
| -rw-r--r-- | src/pl/plpgsql/src/pl_exec.c | 162 |
1 files changed, 96 insertions, 66 deletions
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c index 164c38d2952..2ad4bed0b6d 100644 --- a/src/pl/plpgsql/src/pl_exec.c +++ b/src/pl/plpgsql/src/pl_exec.c @@ -183,14 +183,17 @@ static void exec_move_row(PLpgSQL_execstate *estate, static HeapTuple make_tuple_from_row(PLpgSQL_execstate *estate, PLpgSQL_row *row, TupleDesc tupdesc); -static char *convert_value_to_string(Datum value, Oid valtype); -static Datum exec_cast_value(Datum value, Oid valtype, +static char *convert_value_to_string(PLpgSQL_execstate *estate, + Datum value, Oid valtype); +static Datum exec_cast_value(PLpgSQL_execstate *estate, + Datum value, Oid valtype, Oid reqtype, FmgrInfo *reqinput, Oid reqtypioparam, int32 reqtypmod, bool isnull); -static Datum exec_simple_cast_value(Datum value, Oid valtype, +static Datum exec_simple_cast_value(PLpgSQL_execstate *estate, + Datum value, Oid valtype, Oid reqtype, int32 reqtypmod, bool isnull); static void exec_init_tuple_store(PLpgSQL_execstate *estate); @@ -290,6 +293,8 @@ plpgsql_exec_function(PLpgSQL_function *func, FunctionCallInfo fcinfo) /* If arg is null, treat it as an empty row */ exec_move_row(&estate, NULL, row, NULL, NULL); } + /* clean up after exec_move_row() */ + exec_eval_cleanup(&estate); } break; @@ -425,7 +430,9 @@ plpgsql_exec_function(PLpgSQL_function *func, FunctionCallInfo fcinfo) else { /* Cast value to proper type */ - estate.retval = exec_cast_value(estate.retval, estate.rettype, + estate.retval = exec_cast_value(&estate, + estate.retval, + estate.rettype, func->fn_rettype, &(func->fn_retinput), func->fn_rettypioparam, @@ -1715,7 +1722,7 @@ exec_stmt_fori(PLpgSQL_execstate *estate, PLpgSQL_stmt_fori *stmt) * Get the value of the lower bound */ value = exec_eval_expr(estate, stmt->lower, &isnull, &valtype); - value = exec_cast_value(value, valtype, var->datatype->typoid, + value = exec_cast_value(estate, value, valtype, var->datatype->typoid, &(var->datatype->typinput), var->datatype->typioparam, var->datatype->atttypmod, isnull); @@ -1730,7 +1737,7 @@ exec_stmt_fori(PLpgSQL_execstate *estate, PLpgSQL_stmt_fori *stmt) * Get the value of the upper bound */ value = exec_eval_expr(estate, stmt->upper, &isnull, &valtype); - value = exec_cast_value(value, valtype, var->datatype->typoid, + value = exec_cast_value(estate, value, valtype, var->datatype->typoid, &(var->datatype->typinput), var->datatype->typioparam, var->datatype->atttypmod, isnull); @@ -1747,7 +1754,7 @@ exec_stmt_fori(PLpgSQL_execstate *estate, PLpgSQL_stmt_fori *stmt) if (stmt->step) { value = exec_eval_expr(estate, stmt->step, &isnull, &valtype); - value = exec_cast_value(value, valtype, var->datatype->typoid, + value = exec_cast_value(estate, value, valtype, var->datatype->typoid, &(var->datatype->typinput), var->datatype->typioparam, var->datatype->atttypmod, isnull); @@ -2399,7 +2406,8 @@ exec_stmt_return_next(PLpgSQL_execstate *estate, errmsg("wrong result type supplied in RETURN NEXT"))); /* coerce type if needed */ - retval = exec_simple_cast_value(retval, + retval = exec_simple_cast_value(estate, + retval, var->datatype->typoid, tupdesc->attrs[0]->atttypid, tupdesc->attrs[0]->atttypmod, @@ -2470,7 +2478,8 @@ exec_stmt_return_next(PLpgSQL_execstate *estate, &rettype); /* coerce type if needed */ - retval = exec_simple_cast_value(retval, + retval = exec_simple_cast_value(estate, + retval, rettype, tupdesc->attrs[0]->atttypid, tupdesc->attrs[0]->atttypmod, @@ -2478,8 +2487,6 @@ exec_stmt_return_next(PLpgSQL_execstate *estate, tuplestore_putvalues(estate->tuple_store, tupdesc, &retval, &isNull); - - exec_eval_cleanup(estate); } else { @@ -2496,6 +2503,8 @@ exec_stmt_return_next(PLpgSQL_execstate *estate, heap_freetuple(tuple); } + exec_eval_cleanup(estate); + return PLPGSQL_RC_OK; } @@ -2685,7 +2694,9 @@ exec_stmt_raise(PLpgSQL_execstate *estate, PLpgSQL_stmt_raise *stmt) if (paramisnull) extval = "<NULL>"; else - extval = convert_value_to_string(paramvalue, paramtypeid); + extval = convert_value_to_string(estate, + paramvalue, + paramtypeid); appendStringInfoString(&ds, extval); current_param = lnext(current_param); exec_eval_cleanup(estate); @@ -2723,7 +2734,7 @@ exec_stmt_raise(PLpgSQL_execstate *estate, PLpgSQL_stmt_raise *stmt) (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED), errmsg("RAISE statement option cannot be null"))); - extval = convert_value_to_string(optionvalue, optiontypeid); + extval = convert_value_to_string(estate, optionvalue, optiontypeid); switch (opt->opt_type) { @@ -3141,6 +3152,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate, } /* Clean up */ + exec_eval_cleanup(estate); SPI_freetuptable(SPI_tuptable); } else @@ -3186,7 +3198,10 @@ exec_stmt_dynexecute(PLpgSQL_execstate *estate, errmsg("query string argument of EXECUTE is null"))); /* Get the C-String representation */ - querystr = convert_value_to_string(query, restype); + querystr = convert_value_to_string(estate, query, restype); + + /* copy it out of the temporary context before we clean up */ + querystr = pstrdup(querystr); exec_eval_cleanup(estate); @@ -3319,6 +3334,8 @@ exec_stmt_dynexecute(PLpgSQL_execstate *estate, /* Put the first result row into the target */ exec_move_row(estate, rec, row, tuptab->vals[0], tuptab->tupdesc); } + /* clean up after exec_move_row() */ + exec_eval_cleanup(estate); } else { @@ -3593,6 +3610,7 @@ exec_stmt_fetch(PLpgSQL_execstate *estate, PLpgSQL_stmt_fetch *stmt) else exec_move_row(estate, rec, row, tuptab->vals[0], tuptab->tupdesc); + exec_eval_cleanup(estate); SPI_freetuptable(tuptab); } else @@ -3670,7 +3688,7 @@ exec_assign_expr(PLpgSQL_execstate *estate, PLpgSQL_datum *target, /* ---------- * exec_assign_value Put a value into a target field * - * Note: in some code paths, this may leak memory in the eval_econtext; + * Note: in some code paths, this will leak memory in the eval_econtext; * we assume that will be cleaned up later by exec_eval_cleanup. We cannot * call exec_eval_cleanup here for fear of destroying the input Datum value. * ---------- @@ -3690,7 +3708,10 @@ exec_assign_value(PLpgSQL_execstate *estate, PLpgSQL_var *var = (PLpgSQL_var *) target; Datum newvalue; - newvalue = exec_cast_value(value, valtype, var->datatype->typoid, + newvalue = exec_cast_value(estate, + value, + valtype, + var->datatype->typoid, &(var->datatype->typinput), var->datatype->typioparam, var->datatype->atttypmod, @@ -3703,19 +3724,14 @@ exec_assign_value(PLpgSQL_execstate *estate, var->refname))); /* - * If type is by-reference, make sure we have a freshly - * palloc'd copy; the originally passed value may not live as - * long as the variable! But we don't need to re-copy if - * exec_cast_value performed a conversion; its output must - * already be palloc'd. + * If type is by-reference, copy the new value (which is + * probably in the eval_econtext) into the procedure's + * memory context. */ if (!var->datatype->typbyval && !*isNull) - { - if (newvalue == value) - newvalue = datumCopy(newvalue, - false, - var->datatype->typlen); - } + newvalue = datumCopy(newvalue, + false, + var->datatype->typlen); /* * Now free the old value. (We can't do this any earlier @@ -3831,7 +3847,6 @@ exec_assign_value(PLpgSQL_execstate *estate, Datum *values; bool *nulls; bool *replaces; - void *mustfree; bool attisnull; Oid atttype; int32 atttypmod; @@ -3883,7 +3898,8 @@ exec_assign_value(PLpgSQL_execstate *estate, atttype = SPI_gettypeid(rec->tupdesc, fno + 1); atttypmod = rec->tupdesc->attrs[fno]->atttypmod; attisnull = *isNull; - values[fno] = exec_simple_cast_value(value, + values[fno] = exec_simple_cast_value(estate, + value, valtype, atttype, atttypmod, @@ -3891,15 +3907,6 @@ exec_assign_value(PLpgSQL_execstate *estate, nulls[fno] = attisnull; /* - * Avoid leaking the result of exec_simple_cast_value, if it - * performed a conversion to a pass-by-ref type. - */ - if (!attisnull && values[fno] != value && !get_typbyval(atttype)) - mustfree = DatumGetPointer(values[fno]); - else - mustfree = NULL; - - /* * Now call heap_modify_tuple() to create a new tuple that * replaces the old one in the record. */ @@ -3915,8 +3922,6 @@ exec_assign_value(PLpgSQL_execstate *estate, pfree(values); pfree(nulls); pfree(replaces); - if (mustfree) - pfree(mustfree); break; } @@ -3943,6 +3948,7 @@ exec_assign_value(PLpgSQL_execstate *estate, ArrayType *oldarrayval; ArrayType *newarrayval; SPITupleTable *save_eval_tuptable; + MemoryContext oldcontext; /* * We need to do subscript evaluation, which might require @@ -4031,7 +4037,8 @@ exec_assign_value(PLpgSQL_execstate *estate, estate->eval_tuptable = save_eval_tuptable; /* Coerce source value to match array element type. */ - coerced_value = exec_simple_cast_value(value, + coerced_value = exec_simple_cast_value(estate, + value, valtype, arrayelemtypeid, arraytypmod, @@ -4051,6 +4058,9 @@ exec_assign_value(PLpgSQL_execstate *estate, (oldarrayisnull || *isNull)) return; + /* oldarrayval and newarrayval should be short-lived */ + oldcontext = MemoryContextSwitchTo(estate->eval_econtext->ecxt_per_tuple_memory); + if (oldarrayisnull) oldarrayval = construct_empty_array(arrayelemtypeid); else @@ -4069,12 +4079,7 @@ exec_assign_value(PLpgSQL_execstate *estate, elemtypbyval, elemtypalign); - /* - * Avoid leaking the result of exec_simple_cast_value, if it - * performed a conversion to a pass-by-ref type. - */ - if (!*isNull && coerced_value != value && !elemtypbyval) - pfree(DatumGetPointer(coerced_value)); + MemoryContextSwitchTo(oldcontext); /* * Assign the new array to the base variable. It's never NULL @@ -4086,11 +4091,6 @@ exec_assign_value(PLpgSQL_execstate *estate, exec_assign_value(estate, target, PointerGetDatum(newarrayval), arraytypeid, isNull); - - /* - * Avoid leaking the modified array value, too. - */ - pfree(newarrayval); break; } @@ -4426,7 +4426,7 @@ exec_eval_integer(PLpgSQL_execstate *estate, Oid exprtypeid; exprdatum = exec_eval_expr(estate, expr, isNull, &exprtypeid); - exprdatum = exec_simple_cast_value(exprdatum, exprtypeid, + exprdatum = exec_simple_cast_value(estate, exprdatum, exprtypeid, INT4OID, -1, *isNull); return DatumGetInt32(exprdatum); @@ -4448,7 +4448,7 @@ exec_eval_boolean(PLpgSQL_execstate *estate, Oid exprtypeid; exprdatum = exec_eval_expr(estate, expr, isNull, &exprtypeid); - exprdatum = exec_simple_cast_value(exprdatum, exprtypeid, + exprdatum = exec_simple_cast_value(estate, exprdatum, exprtypeid, BOOLOID, -1, *isNull); return DatumGetBool(exprdatum); @@ -4643,7 +4643,10 @@ exec_for_query(PLpgSQL_execstate *estate, PLpgSQL_stmt_forq *stmt, * through with found = false. */ if (n <= 0) + { exec_move_row(estate, rec, row, NULL, tuptab->tupdesc); + exec_eval_cleanup(estate); + } else found = true; /* processed at least one tuple */ @@ -4660,6 +4663,7 @@ exec_for_query(PLpgSQL_execstate *estate, PLpgSQL_stmt_forq *stmt, * Assign the tuple to the target */ exec_move_row(estate, rec, row, tuptab->vals[i], tuptab->tupdesc); + exec_eval_cleanup(estate); /* * Execute the statements @@ -5012,6 +5016,9 @@ plpgsql_param_fetch(ParamListInfo params, int paramid) /* ---------- * exec_move_row Move one tuple's values into a record or row + * + * Since this uses exec_assign_value, caller should eventually call + * exec_eval_cleanup to prevent long-term memory leaks. * ---------- */ static void @@ -5212,28 +5219,44 @@ make_tuple_from_row(PLpgSQL_execstate *estate, /* ---------- * convert_value_to_string Convert a non-null Datum to C string * - * Note: callers generally assume that the result is a palloc'd string and - * should be pfree'd. This is not all that safe an assumption ... + * Note: the result is in the estate's eval_econtext, and will be cleared + * by the next exec_eval_cleanup() call. The invoked output function might + * leave additional cruft there as well, so just pfree'ing the result string + * would not be enough to avoid memory leaks if we did not do it like this. + * In most usages the Datum being passed in is also in that context (if + * pass-by-reference) and so an exec_eval_cleanup() call is needed anyway. * * Note: not caching the conversion function lookup is bad for performance. * ---------- */ static char * -convert_value_to_string(Datum value, Oid valtype) +convert_value_to_string(PLpgSQL_execstate *estate, Datum value, Oid valtype) { + char *result; + MemoryContext oldcontext; Oid typoutput; bool typIsVarlena; + oldcontext = MemoryContextSwitchTo(estate->eval_econtext->ecxt_per_tuple_memory); getTypeOutputInfo(valtype, &typoutput, &typIsVarlena); - return OidOutputFunctionCall(typoutput, value); + result = OidOutputFunctionCall(typoutput, value); + MemoryContextSwitchTo(oldcontext); + + return result; } /* ---------- * exec_cast_value Cast a value if required + * + * Note: the estate's eval_econtext is used for temporary storage, and may + * also contain the result Datum if we have to do a conversion to a pass- + * by-reference data type. Be sure to do an exec_eval_cleanup() call when + * done with the result. * ---------- */ static Datum -exec_cast_value(Datum value, Oid valtype, +exec_cast_value(PLpgSQL_execstate *estate, + Datum value, Oid valtype, Oid reqtype, FmgrInfo *reqinput, Oid reqtypioparam, @@ -5241,25 +5264,27 @@ exec_cast_value(Datum value, Oid valtype, bool isnull) { /* - * If the type of the queries return value isn't that of the variable, - * convert it. + * If the type of the given value isn't what's requested, convert it. */ if (valtype != reqtype || reqtypmod != -1) { + MemoryContext oldcontext; + + oldcontext = MemoryContextSwitchTo(estate->eval_econtext->ecxt_per_tuple_memory); if (!isnull) { char *extval; - extval = convert_value_to_string(value, valtype); + extval = convert_value_to_string(estate, value, valtype); value = InputFunctionCall(reqinput, extval, reqtypioparam, reqtypmod); - pfree(extval); } else { value = InputFunctionCall(reqinput, NULL, reqtypioparam, reqtypmod); } + MemoryContextSwitchTo(oldcontext); } return value; @@ -5274,7 +5299,8 @@ exec_cast_value(Datum value, Oid valtype, * ---------- */ static Datum -exec_simple_cast_value(Datum value, Oid valtype, +exec_simple_cast_value(PLpgSQL_execstate *estate, + Datum value, Oid valtype, Oid reqtype, int32 reqtypmod, bool isnull) { @@ -5288,7 +5314,8 @@ exec_simple_cast_value(Datum value, Oid valtype, fmgr_info(typinput, &finfo_input); - value = exec_cast_value(value, + value = exec_cast_value(estate, + value, valtype, reqtype, &finfo_input, @@ -5929,7 +5956,10 @@ exec_dynquery_with_params(PLpgSQL_execstate *estate, errmsg("query string argument of EXECUTE is null"))); /* Get the C-String representation */ - querystr = convert_value_to_string(query, restype); + querystr = convert_value_to_string(estate, query, restype); + + /* copy it out of the temporary context before we clean up */ + querystr = pstrdup(querystr); exec_eval_cleanup(estate); |