Boolean data type support, added in Firebird 3. Fixes #74462.

ext/pdo_firebird/firebird_statement.c

@@ -1,4 +1,4 @@
-/*
+/*
   +----------------------------------------------------------------------+
   | PHP Version 7                                                        |
   +----------------------------------------------------------------------+
@@ -229,6 +229,9 @@ static int firebird_stmt_describe(pdo_stmt_t *stmt, int colno) /* {{{ */
 #endif
 				col->param_type = PDO_PARAM_INT;
 				break;
+			case SQL_BOOLEAN:
+				col->param_type = PDO_PARAM_BOOL;
+				break;
 			default:
 				col->param_type = PDO_PARAM_STR;
 				break;
@@ -416,6 +419,11 @@ static int firebird_stmt_get_col(pdo_stmt_t *stmt, int colno, char **ptr,  /* {{
 					*ptr = FETCH_BUF(S->fetch_buf[colno], char, CHAR_BUF_LEN, NULL);
 					*len = slprintf(*ptr, CHAR_BUF_LEN, "%F" , *(double*)var->sqldata);
 					break;
+				case SQL_BOOLEAN:
+					*len = sizeof(zend_bool);
+					*ptr = FETCH_BUF(S->fetch_buf[colno], zend_bool, 1, NULL);
+					*(zend_bool*)*ptr = *(FB_BOOLEAN*)var->sqldata;
+					break;
 				case SQL_TYPE_DATE:
 					isc_decode_sql_date((ISC_DATE*)var->sqldata, &t);
 					fmt = S->H->date_format ? S->H->date_format : PDO_FB_DEF_DATE_FMT;

ext/pdo_firebird/tests/bug_74462.phpt

@@ -0,0 +1,29 @@
+--TEST--
+PDO_Firebird: Bug #74462 Returns only NULLs for boolean fields
+--SKIPIF--
+<?php if (!extension_loaded('interbase') || !extension_loaded('pdo_firebird')) die('skip'); 
+?>
+--FILE--
+<?php
+require 'testdb.inc';
+$C = new PDO('firebird:dbname='.$test_base, $user, $password) or die;
+@$C->exec('drop table atable');
+$C->exec('create table atable (id integer not null, abool boolean)');
+$C->exec('insert into atable (id, abool) values (1, true)');
+$C->exec('insert into atable (id, abool) values (2, false)');
+$C->exec('insert into atable (id, abool) values (3, null)');
+$S = $C->query('select abool from atable order by id');
+$D = $S->fetchAll(PDO::FETCH_COLUMN);
+unset($S);
+unset($C);
+var_dump($D);
+?>
+--EXPECT--
+array(3) {
+  [0]=>
+  bool(true)
+  [1]=>
+  bool(false)
+  [2]=>
+  NULL
+}