Fix pg_fetch_object() when an error occurs in subroutine

This is a follow-up of GH-20068

Author: Girgias

ext/pgsql/pgsql.c

@@ -1978,7 +1978,7 @@ PHP_FUNCTION(pg_fetch_result)
 /* }}} */
 
 /* {{{ void php_pgsql_fetch_hash */
-static void php_pgsql_fetch_hash(zval *return_value, const zval *result, zend_long row, bool row_is_null, zend_long result_type)
+static bool php_pgsql_fetch_hash(zval *return_value, const zval *result, zend_long row, bool row_is_null, zend_long result_type)
 {
 	PGresult            *pgsql_result;
 	pgsql_result_handle *pg_result;
@@ -1987,31 +1987,34 @@ static void php_pgsql_fetch_hash(zval *return_value, const zval *result, zend_lo
 
 	if (!row_is_null && row < 0) {
 		zend_argument_value_error(2, "must be greater than or equal to 0");
-		RETURN_THROWS();
+		return false;
 	}
 
 	if (!(result_type & PGSQL_BOTH)) {
 		zend_argument_value_error(3, "must be one of PGSQL_ASSOC, PGSQL_NUM, or PGSQL_BOTH");
-		RETURN_THROWS();
+		return false;
 	}
 
 	pg_result = Z_PGSQL_RESULT_P(result);
-	CHECK_PGSQL_RESULT(pg_result);
+	if (UNEXPECTED(pg_result->result == NULL)) {
+		zend_throw_error(NULL, "PostgreSQL result has already been closed");
+		return false;
+	}
 	pgsql_result = pg_result->result;
 
 	if (!row_is_null) {
 		if (row >= PQntuples(pgsql_result)) {
 			php_error_docref(NULL, E_WARNING, "Unable to jump to row " ZEND_LONG_FMT " on PostgreSQL result index " ZEND_LONG_FMT,
 							row, Z_LVAL_P(result));
-			RETURN_FALSE;
+			return false;
 		}
 		pgsql_row = (int)row;
 		pg_result->row = pgsql_row;
 	} else {
 		/* If 2nd param is NULL, use internal row counter to access next row */
 		pgsql_row = pg_result->row;
 		if (pgsql_row < 0 || pgsql_row >= PQntuples(pgsql_result)) {
-			RETURN_FALSE;
+			return false;
 		}
 		pg_result->row++;
 	}
@@ -2042,6 +2045,7 @@ static void php_pgsql_fetch_hash(zval *return_value, const zval *result, zend_lo
 			}
 		}
 	}
+	return true;
 }
 /* }}} */
 
@@ -2060,7 +2064,11 @@ PHP_FUNCTION(pg_fetch_row)
 		Z_PARAM_LONG(result_type)
 	ZEND_PARSE_PARAMETERS_END();
 
-	php_pgsql_fetch_hash(return_value, result, row, row_is_null, result_type);
+	/* If php_pgsql_fetch_hash() returns true then we have a properly initialized retval */
+	if (UNEXPECTED(!php_pgsql_fetch_hash(return_value, result, row, row_is_null, result_type))) {
+		/* Either an exception is thrown, or we return false */
+		RETURN_FALSE;
+	}
 }
 /* }}} */
 
@@ -2077,7 +2085,11 @@ PHP_FUNCTION(pg_fetch_assoc)
 		Z_PARAM_LONG_OR_NULL(row, row_is_null)
 	ZEND_PARSE_PARAMETERS_END();
 
-	php_pgsql_fetch_hash(return_value, result, row, row_is_null, PGSQL_ASSOC);
+	/* If php_pgsql_fetch_hash() returns true then we have a properly initialized retval */
+	if (UNEXPECTED(!php_pgsql_fetch_hash(return_value, result, row, row_is_null, PGSQL_ASSOC))) {
+		/* Either an exception is thrown, or we return false */
+		RETURN_FALSE;
+	}
 }
 /* }}} */
 
@@ -2096,7 +2108,11 @@ PHP_FUNCTION(pg_fetch_array)
 		Z_PARAM_LONG(result_type)
 	ZEND_PARSE_PARAMETERS_END();
 
-	php_pgsql_fetch_hash(return_value, result, row, row_is_null, result_type);
+	/* If php_pgsql_fetch_hash() returns true then we have a properly initialized retval */
+	if (UNEXPECTED(!php_pgsql_fetch_hash(return_value, result, row, row_is_null, result_type))) {
+		/* Either an exception is thrown, or we return false */
+		RETURN_FALSE;
+	}
 }
 /* }}} */
 
@@ -2132,7 +2148,11 @@ PHP_FUNCTION(pg_fetch_object)
 	/* pg_fetch_object() allowed result_type used to be. 3rd parameter
 	   must be allowed for compatibility */
 	zval dataset;
-	php_pgsql_fetch_hash(&dataset, result, row, row_is_null, PGSQL_ASSOC);
+	/* If php_pgsql_fetch_hash() returns true then we have a properly initialized retval */
+	if (UNEXPECTED(!php_pgsql_fetch_hash(&dataset, result, row, row_is_null, PGSQL_ASSOC))) {
+		/* Either an exception is thrown, or we return false */
+		RETURN_FALSE;
+	}
 
 	// TODO: Check CE is an instantiable class earlier?
 	zend_result obj_initialized = object_init_ex(return_value, ce);