Need to do SPI_push/SPI_pop around expression evaluation in plpgsql.

tglsfdc · tglsfdc · commit a5b153ff5194 · 2016-11-06T12:09:36.000-05:00
We must do this in case the expression evaluation results in calling another plpgsql function (or, really, anything using SPI). I missed the need for this when I converted exec_cast_value() from doing a simple InputFunctionCall() to doing ExecEvalExpr() in commit 1345cc6. There is a SPI_push_conditional in InputFunctionCall(), so that there was no bug before that. Per bug #14414 from Marcos Castedo. Add a regression test based on his example, which was that a plpgsql function in a domain check constraint didn't work when assigning to a domain-type variable within plpgsql. Report: <20161106010947.1387.66380@wrigleys.postgresql.org>
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
@@ -6102,6 +6102,8 @@ exec_cast_value(PLpgSQL_execstate *estate,
 			ExprContext *econtext = estate->eval_econtext;
 			MemoryContext oldcontext;
 
+			SPI_push();
+
 			oldcontext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
 
 			econtext->caseValue_datum = value;
@@ -6115,6 +6117,8 @@ exec_cast_value(PLpgSQL_execstate *estate,
 			cast_entry->cast_in_use = false;
 
 			MemoryContextSwitchTo(oldcontext);
+
+			SPI_pop();
 		}
 	}
 
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
@@ -5643,3 +5643,22 @@ end;
 $$;
 ERROR:  unhandled assertion
 CONTEXT:  PL/pgSQL function inline_code_block line 3 at ASSERT
+-- Test use of plpgsql in a domain check constraint (cf. bug #14414)
+create function plpgsql_domain_check(val int) returns boolean as $$
+begin return val > 0; end
+$$ language plpgsql immutable;
+create domain plpgsql_domain as integer check(plpgsql_domain_check(value));
+do $$
+declare v_test plpgsql_domain;
+begin
+  v_test := 1;
+end;
+$$;
+do $$
+declare v_test plpgsql_domain := 1;
+begin
+  v_test := 0;  -- fail
+end;
+$$;
+ERROR:  value for domain plpgsql_domain violates check constraint "plpgsql_domain_check"
+CONTEXT:  PL/pgSQL function inline_code_block line 4 at assignment
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
@@ -4428,3 +4428,25 @@ exception when others then
   null; -- do nothing
 end;
 $$;
+
+-- Test use of plpgsql in a domain check constraint (cf. bug #14414)
+
+create function plpgsql_domain_check(val int) returns boolean as $$
+begin return val > 0; end
+$$ language plpgsql immutable;
+
+create domain plpgsql_domain as integer check(plpgsql_domain_check(value));
+
+do $$
+declare v_test plpgsql_domain;
+begin
+  v_test := 1;
+end;
+$$;
+
+do $$
+declare v_test plpgsql_domain := 1;
+begin
+  v_test := 0;  -- fail
+end;
+$$;

Original file line number	Diff line number	Diff line change
`@@ -6102,6 +6102,8 @@ exec_cast_value(PLpgSQL_execstate *estate,`
`6102`	`6102`	`ExprContext *econtext = estate->eval_econtext;`
`6103`	`6103`	`MemoryContext oldcontext;`
`6104`	`6104`
	`6105`	`+ SPI_push();`
	`6106`	`+`
`6105`	`6107`	`oldcontext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);`
`6106`	`6108`
`6107`	`6109`	`econtext->caseValue_datum = value;`
`@@ -6115,6 +6117,8 @@ exec_cast_value(PLpgSQL_execstate *estate,`
`6115`	`6117`	`cast_entry->cast_in_use = false;`
`6116`	`6118`
`6117`	`6119`	`MemoryContextSwitchTo(oldcontext);`
	`6120`	`+`
	`6121`	`+ SPI_pop();`
`6118`	`6122`	`}`
`6119`	`6123`	`}`
`6120`	`6124`