Fix more strcmp() calls using boolean-like comparisons for result checks

Such calls can confuse the reader as strcmp() uses an integer as result.
The places patched here have been spotted by Thomas Munro, David Rowley
and myself.

Author: Michael Paquier
Reviewed-by: David Rowley
Discussion: https://postgr.es/m/20190411021946.GG2728@paquier.xyz

contrib/spi/refint.c

@@ -473,9 +473,12 @@ check_foreign_key(PG_FUNCTION_ARGS)
 						nv = SPI_getvalue(newtuple, tupdesc, fn);
 						type = SPI_gettype(tupdesc, fn);
 
-						if ((strcmp(type, "text") && strcmp(type, "varchar") &&
-							 strcmp(type, "char") && strcmp(type, "bpchar") &&
-							 strcmp(type, "date") && strcmp(type, "timestamp")) == 0)
+						if (strcmp(type, "text") == 0 ||
+							strcmp(type, "varchar") == 0 ||
+							strcmp(type, "char") == 0 ||
+							strcmp(type, "bpchar") == 0 ||
+							strcmp(type, "date") == 0 ||
+							strcmp(type, "timestamp") == 0)
 							is_char_type = 1;
 #ifdef	DEBUG_QUERY
 						elog(DEBUG4, "check_foreign_key Debug value %s type %s %d",

src/backend/commands/lockcmds.c

@@ -219,7 +219,8 @@ LockViewRecurse_walker(Node *node, LockViewRecurse_context *context)
 			 * skipped.
 			 */
 			if (relid == context->viewoid &&
-				(!strcmp(rte->eref->aliasname, "old") || !strcmp(rte->eref->aliasname, "new")))
+				(strcmp(rte->eref->aliasname, "old") == 0 ||
+				 strcmp(rte->eref->aliasname, "new") == 0))
 				continue;
 
 			/* Currently, we only allow plain tables or views to be locked. */

src/backend/tsearch/spell.c

@@ -1749,8 +1749,8 @@ NISortDictionary(IspellDict *Conf)
 		naffix = 0;
 		for (i = 0; i < Conf->nspell; i++)
 		{
-			if (i == 0
-				|| strcmp(Conf->Spell[i]->p.flag, Conf->Spell[i - 1]->p.flag))
+			if (i == 0 ||
+				strcmp(Conf->Spell[i]->p.flag, Conf->Spell[i - 1]->p.flag) != 0)
 				naffix++;
 		}
 
@@ -1764,8 +1764,8 @@ NISortDictionary(IspellDict *Conf)
 		curaffix = -1;
 		for (i = 0; i < Conf->nspell; i++)
 		{
-			if (i == 0
-				|| strcmp(Conf->Spell[i]->p.flag, Conf->AffixData[curaffix]))
+			if (i == 0 ||
+				strcmp(Conf->Spell[i]->p.flag, Conf->AffixData[curaffix]) != 0)
 			{
 				curaffix++;
 				Assert(curaffix < naffix);

src/test/modules/test_rls_hooks/test_rls_hooks.c

@@ -75,8 +75,8 @@ test_rls_hooks_permissive(CmdType cmdtype, Relation relation)
 	ParseState *qual_pstate;
 	RangeTblEntry *rte;
 
-	if (strcmp(RelationGetRelationName(relation), "rls_test_permissive")
-		&& strcmp(RelationGetRelationName(relation), "rls_test_both"))
+	if (strcmp(RelationGetRelationName(relation), "rls_test_permissive") != 0 &&
+		strcmp(RelationGetRelationName(relation), "rls_test_both") != 0)
 		return NIL;
 
 	qual_pstate = make_parsestate(NULL);
@@ -140,8 +140,8 @@ test_rls_hooks_restrictive(CmdType cmdtype, Relation relation)
 	RangeTblEntry *rte;
 
 
-	if (strcmp(RelationGetRelationName(relation), "rls_test_restrictive")
-		&& strcmp(RelationGetRelationName(relation), "rls_test_both"))
+	if (strcmp(RelationGetRelationName(relation), "rls_test_restrictive") != 0 &&
+		strcmp(RelationGetRelationName(relation), "rls_test_both") != 0)
 		return NIL;
 
 	qual_pstate = make_parsestate(NULL);