From aaaf9449ec6be62cb0d30ed3588dc384f56274bf Mon Sep 17 00:00:00 2001 From: Amit Langote Date: Wed, 24 Jan 2024 13:35:22 +0900 Subject: [PATCH] Add soft error handling to some expression nodes MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adjusts the code for CoerceViaIO and CoerceToDomain expression nodes to handle errors softly. For CoerceViaIo, this adds a new ExprEvalStep opcode EEOP_IOCOERCE_SAFE, which is implemented in the new accompanying function ExecEvalCoerceViaIOSafe(). The only difference from EEOP_IOCOERCE's inline implementation is that the input function receives an ErrorSaveContext via the function's FunctionCallInfo.context, which it can use to handle errors softly. For CoerceToDomain, this simply entails replacing the ereport() in ExecEvalConstraintNotNull() and ExecEvalConstraintCheck() by errsave() passing it the ErrorSaveContext passed in the expression's ExprEvalStep. In both cases, the ErrorSaveContext to be used is passed by setting ExprState.escontext to point to it before calling ExecInitExprRec() on the expression tree whose errors are to be handled softly. Note that there's no functional change as of this commit as no call site of ExecInitExprRec() has been changed. This is intended for implementing new SQL/JSON expression nodes in future commits. Extracted from a much larger patch to add SQL/JSON query functions. Author: Nikita Glukhov Author: Teodor Sigaev Author: Oleg Bartunov Author: Alexander Korotkov Author: Andrew Dunstan Author: Amit Langote Reviewers have included (in no particular order) Andres Freund, Alexander Korotkov, Pavel Stehule, Andrew Alsup, Erik Rijkers, Zihong Yu, Himanshu Upadhyaya, Daniel Gustafsson, Justin Pryzby, Álvaro Herrera, Jian He, Peter Eisentraut Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de Discussion: https://postgr.es/m/abd9b83b-aa66-f230-3d6d-734817f0995d%40postgresql.org Discussion: https://postgr.es/m/CA+HiwqHROpf9e644D8BRqYvaAPmgBZVup-xKMDPk-nd4EpgzHw@mail.gmail.com Discussion: https://postgr.es/m/CA+HiwqE4XTdfb1nW=Ojoy_tQSRhYt-q_kb6i5d4xcKyrLC1Nbg@mail.gmail.com --- src/backend/executor/execExpr.c | 8 ++- src/backend/executor/execExprInterp.c | 80 ++++++++++++++++++++++++++- src/backend/jit/llvm/llvmjit_expr.c | 6 ++ src/backend/jit/llvm/llvmjit_types.c | 1 + src/include/executor/execExpr.h | 4 ++ src/include/nodes/execnodes.h | 7 +++ 6 files changed, 103 insertions(+), 3 deletions(-) diff --git a/src/backend/executor/execExpr.c b/src/backend/executor/execExpr.c index 91df2009bee..3181b1136a2 100644 --- a/src/backend/executor/execExpr.c +++ b/src/backend/executor/execExpr.c @@ -1560,7 +1560,10 @@ ExecInitExprRec(Expr *node, ExprState *state, * We don't check permissions here as a type's input/output * function are assumed to be executable by everyone. */ - scratch.opcode = EEOP_IOCOERCE; + if (state->escontext == NULL) + scratch.opcode = EEOP_IOCOERCE; + else + scratch.opcode = EEOP_IOCOERCE_SAFE; /* lookup the source type's output function */ scratch.d.iocoerce.finfo_out = palloc0(sizeof(FmgrInfo)); @@ -1596,6 +1599,8 @@ ExecInitExprRec(Expr *node, ExprState *state, fcinfo_in->args[2].value = Int32GetDatum(-1); fcinfo_in->args[2].isnull = false; + fcinfo_in->context = (Node *) state->escontext; + ExprEvalPushStep(state, &scratch); break; } @@ -3303,6 +3308,7 @@ ExecInitCoerceToDomain(ExprEvalStep *scratch, CoerceToDomain *ctest, /* we'll allocate workspace only if needed */ scratch->d.domaincheck.checkvalue = NULL; scratch->d.domaincheck.checknull = NULL; + scratch->d.domaincheck.escontext = state->escontext; /* * Evaluate argument - it's fine to directly store it into resv/resnull, diff --git a/src/backend/executor/execExprInterp.c b/src/backend/executor/execExprInterp.c index 3c17cc6b1e1..3f20f1dd314 100644 --- a/src/backend/executor/execExprInterp.c +++ b/src/backend/executor/execExprInterp.c @@ -63,6 +63,7 @@ #include "executor/nodeSubplan.h" #include "funcapi.h" #include "miscadmin.h" +#include "nodes/miscnodes.h" #include "nodes/nodeFuncs.h" #include "parser/parsetree.h" #include "pgstat.h" @@ -452,6 +453,7 @@ ExecInterpExpr(ExprState *state, ExprContext *econtext, bool *isnull) &&CASE_EEOP_CASE_TESTVAL, &&CASE_EEOP_MAKE_READONLY, &&CASE_EEOP_IOCOERCE, + &&CASE_EEOP_IOCOERCE_SAFE, &&CASE_EEOP_DISTINCT, &&CASE_EEOP_NOT_DISTINCT, &&CASE_EEOP_NULLIF, @@ -1150,6 +1152,9 @@ ExecInterpExpr(ExprState *state, ExprContext *econtext, bool *isnull) * Evaluate a CoerceViaIO node. This can be quite a hot path, so * inline as much work as possible. The source value is in our * result variable. + * + * Also look at ExecEvalCoerceViaIOSafe() if you change anything + * here. */ char *str; @@ -1205,6 +1210,12 @@ ExecInterpExpr(ExprState *state, ExprContext *econtext, bool *isnull) EEO_NEXT(); } + EEO_CASE(EEOP_IOCOERCE_SAFE) + { + ExecEvalCoerceViaIOSafe(state, op); + EEO_NEXT(); + } + EEO_CASE(EEOP_DISTINCT) { /* @@ -2510,6 +2521,71 @@ ExecEvalParamExtern(ExprState *state, ExprEvalStep *op, ExprContext *econtext) errmsg("no value found for parameter %d", paramId))); } +/* + * Evaluate a CoerceViaIO node in soft-error mode. + * + * The source value is in op's result variable. + * + * Note: This implements EEOP_IOCOERCE_SAFE. If you change anything here, + * also look at the inline code for EEOP_IOCOERCE. + */ +void +ExecEvalCoerceViaIOSafe(ExprState *state, ExprEvalStep *op) +{ + char *str; + + /* call output function (similar to OutputFunctionCall) */ + if (*op->resnull) + { + /* output functions are not called on nulls */ + str = NULL; + } + else + { + FunctionCallInfo fcinfo_out; + + fcinfo_out = op->d.iocoerce.fcinfo_data_out; + fcinfo_out->args[0].value = *op->resvalue; + fcinfo_out->args[0].isnull = false; + + fcinfo_out->isnull = false; + str = DatumGetCString(FunctionCallInvoke(fcinfo_out)); + + /* OutputFunctionCall assumes result isn't null */ + Assert(!fcinfo_out->isnull); + } + + /* call input function (similar to InputFunctionCallSafe) */ + if (!op->d.iocoerce.finfo_in->fn_strict || str != NULL) + { + FunctionCallInfo fcinfo_in; + + fcinfo_in = op->d.iocoerce.fcinfo_data_in; + fcinfo_in->args[0].value = PointerGetDatum(str); + fcinfo_in->args[0].isnull = *op->resnull; + /* second and third arguments are already set up */ + + /* ErrorSaveContext must be present. */ + Assert(IsA(fcinfo_in->context, ErrorSaveContext)); + + fcinfo_in->isnull = false; + *op->resvalue = FunctionCallInvoke(fcinfo_in); + + if (SOFT_ERROR_OCCURRED(fcinfo_in->context)) + { + *op->resnull = true; + *op->resvalue = (Datum) 0; + return; + } + + /* Should get null result if and only if str is NULL */ + if (str == NULL) + Assert(*op->resnull); + else + Assert(!*op->resnull); + } +} + /* * Evaluate a SQLValueFunction expression. */ @@ -3730,7 +3806,7 @@ void ExecEvalConstraintNotNull(ExprState *state, ExprEvalStep *op) { if (*op->resnull) - ereport(ERROR, + errsave((Node *) op->d.domaincheck.escontext, (errcode(ERRCODE_NOT_NULL_VIOLATION), errmsg("domain %s does not allow null values", format_type_be(op->d.domaincheck.resulttype)), @@ -3745,7 +3821,7 @@ ExecEvalConstraintCheck(ExprState *state, ExprEvalStep *op) { if (!*op->d.domaincheck.checknull && !DatumGetBool(*op->d.domaincheck.checkvalue)) - ereport(ERROR, + errsave((Node *) op->d.domaincheck.escontext, (errcode(ERRCODE_CHECK_VIOLATION), errmsg("value for domain %s violates check constraint \"%s\"", format_type_be(op->d.domaincheck.resulttype), diff --git a/src/backend/jit/llvm/llvmjit_expr.c b/src/backend/jit/llvm/llvmjit_expr.c index 33161d812f2..09994503b15 100644 --- a/src/backend/jit/llvm/llvmjit_expr.c +++ b/src/backend/jit/llvm/llvmjit_expr.c @@ -1431,6 +1431,12 @@ llvm_compile_expr(ExprState *state) break; } + case EEOP_IOCOERCE_SAFE: + build_EvalXFunc(b, mod, "ExecEvalCoerceViaIOSafe", + v_state, op); + LLVMBuildBr(b, opblocks[opno + 1]); + break; + case EEOP_DISTINCT: case EEOP_NOT_DISTINCT: { diff --git a/src/backend/jit/llvm/llvmjit_types.c b/src/backend/jit/llvm/llvmjit_types.c index 5212f529c84..47c9daf4023 100644 --- a/src/backend/jit/llvm/llvmjit_types.c +++ b/src/backend/jit/llvm/llvmjit_types.c @@ -162,6 +162,7 @@ void *referenced_functions[] = ExecEvalRow, ExecEvalRowNotNull, ExecEvalRowNull, + ExecEvalCoerceViaIOSafe, ExecEvalSQLValueFunction, ExecEvalScalarArrayOp, ExecEvalHashedScalarArrayOp, diff --git a/src/include/executor/execExpr.h b/src/include/executor/execExpr.h index a20c539a253..a28ddcdd771 100644 --- a/src/include/executor/execExpr.h +++ b/src/include/executor/execExpr.h @@ -16,6 +16,7 @@ #include "executor/nodeAgg.h" #include "nodes/execnodes.h" +#include "nodes/miscnodes.h" /* forward references to avoid circularity */ struct ExprEvalStep; @@ -168,6 +169,7 @@ typedef enum ExprEvalOp /* evaluate assorted special-purpose expression types */ EEOP_IOCOERCE, + EEOP_IOCOERCE_SAFE, EEOP_DISTINCT, EEOP_NOT_DISTINCT, EEOP_NULLIF, @@ -547,6 +549,7 @@ typedef struct ExprEvalStep bool *checknull; /* OID of domain type */ Oid resulttype; + ErrorSaveContext *escontext; } domaincheck; /* for EEOP_CONVERT_ROWTYPE */ @@ -776,6 +779,7 @@ extern void ExecEvalParamExec(ExprState *state, ExprEvalStep *op, ExprContext *econtext); extern void ExecEvalParamExtern(ExprState *state, ExprEvalStep *op, ExprContext *econtext); +extern void ExecEvalCoerceViaIOSafe(ExprState *state, ExprEvalStep *op); extern void ExecEvalSQLValueFunction(ExprState *state, ExprEvalStep *op); extern void ExecEvalCurrentOfExpr(ExprState *state, ExprEvalStep *op); extern void ExecEvalNextValueExpr(ExprState *state, ExprEvalStep *op); diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 561fdd98f1b..444a5f0fd57 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -34,6 +34,7 @@ #include "fmgr.h" #include "lib/ilist.h" #include "lib/pairingheap.h" +#include "nodes/miscnodes.h" #include "nodes/params.h" #include "nodes/plannodes.h" #include "nodes/tidbitmap.h" @@ -129,6 +130,12 @@ typedef struct ExprState Datum *innermost_domainval; bool *innermost_domainnull; + + /* + * For expression nodes that support soft errors. Should be set to NULL + * before calling ExecInitExprRec() if the caller wants errors thrown. + */ + ErrorSaveContext *escontext; } ExprState;