[BUG]: Phalcon\Image\Adapter\Gd throwing an exception for the text function

[nickweavers]

Questions? Forum: https://phalcon.link/forum or Discord: https://phalcon.link/discord

Describe the bug
Phalcon\Image\Adapter\Gd throwing an exception for the text function
I have described the issue here and what I have done to investigate:
https://stackoverflow.com/questions/64541937/phalcon-image-adapter-gd-throwing-an-exception-for-the-text-function
But I think this must be a bug because I am calling the text function with the correct parameters as per the Phalcon 3.4 docs.

I have the following in my code:

use Phalcon\Image\Adapter\GD as Image;
...
    $imagePath = BASE_DIR . '/public/img/map-icons/' . $client->getId() . '/' . $file;
    $image = new Image($imagePath);
...
    $fontFile = $this->getFontPath();
    $image->text($text, $x, $y, 1, '#FFFFFF', $fontSize, $fontFile);

Under Phalcon 1.3.4 and php 5.4.45 it works fine, but when I migrated the application to a new server running Phalcon version 3.4.5 and php 7.3.17 the $image->text($text, $x, $y, 1, '#FFFFFF', $fontSize, $fontFile); is giving the following error:

Project staging.api.my-domain.com raised exception class Phalcon\lmage\Exception with message "Call to imagettfbboxO failed" at gd.zep, line 357

The literal values being passed to $image->text(..) are as follows:

$image->text(H, 9, 20, 1, '#FFFFFF', 11, '/var/www/vhosts/staging.api.mydomain.com/src/fonts/arialbd.ttf');

When I try the example for PHP's imagettfbbox given on the page here https://www.php.net/manual/en/function.imagettfbbox.php the example works and shows a white box with text written across it diagonally.

So it doesn't appear to be a problem with PHP imagettfbbox.

Details

• Phalcon version: 3.4.5
• PHP Version: 7.3.17
• Operating System: Amazon Linux (an EC2)
• Installation type: sudo yum-config-manager --enable remi-php73
• Zephir version (if any):
• Server: Apache
• Other related info (Database, table schema):

Additional context
Here are the php extensions that are installed:

$ php -m
[PHP Modules]
bcmath
bz2
calendar
Core
ctype
curl
date
dbg
dom
exif
fileinfo
filter
ftp
gd
gettext
hash
iconv
json
libxml
mbstring
memcached
mysqli
mysqlnd
openssl
pcntl
pcre
PDO
pdo_mysql
pdo_sqlite
phalcon
Phar
posix
readline
Reflection
session
shmop
SimpleXML
sockets
SPL
sqlite3
standard
sysvmsg
sysvsem
sysvshm
tokenizer
wddx
xml
xmlreader
xmlwriter
xsl
zip
zlib

[nickweavers]

I have created a small test case:

<?php
require('../vendor/autoload.php'); 
use Phalcon\Image\Adapter\GD as Image;
$imagePath = './img/map-icons/sebroche/house.png';
$image = new Image($imagePath);
$fontPath = '../fonts/arialbd.ttf';
$image->text('Hello', 20, 20, 9, '#FFFFFF', 10, $fontPath);
?>

Here's the output when I run it from the cli:

$ php test.php
PHP Fatal error:  Uncaught Phalcon\Image\Exception: Call to imagettfbbox() failed in phalcon/image/adapter/gd.zep:357
Stack trace:
#0 [internal function]: Phalcon\Image\Adapter\Gd->_text('Hello', 20, 20, 9, 255, 255, 255, 10, '../fonts/arialb...')
#1 /var/www/vhosts/staging.api.mydomain.com/src/public/test.php(8): Phalcon\Image\Adapter->text('Hello', 20, 20, 9, '#FFFFFF', 10, '../fonts/arialb...')
#2 {main}
  thrown in phalcon/image/adapter/gd.zep on line 357

[Jeckerson]

Related #14950

[Jeckerson]

@nickweavers Please try to specify absolute path to the font inside $fontPath variable.

[nickweavers]

Okay, I have updated my example to use absolute paths:

<?php
require('../vendor/autoload.php'); 
use Phalcon\Image\Adapter\GD as Image;
$imagePath = '/var/www/vhosts/staging.api-mydomain.com/src/public/img/map-icons/sebroche/house.png';
if (!file_exists($imagePath)) {
    die("File {$imagePath} does not exists");
}
$image = new Image($imagePath);
$fontPath = '/var/www/vhosts/staging.api-mydomain.com/src/fonts/arialbd.ttf';
if (!file_exists($fontPath)) {
    die("File {$fontPath} does not exists");
}
$image->text('Hello', 20, 20, 9, '#FFFFFF', 10, $fontPath);  
?>

but I still get the error:

$ php test.php
PHP Fatal error:  Uncaught Phalcon\Image\Exception: Call to imagettfbbox() failed in phalcon/image/adapter/gd.zep:357
Stack trace:
#0 [internal function]: Phalcon\Image\Adapter\Gd->_text('Hello', 20, 20, 9, 255, 255, 255, 10, '/var/www/vhosts...')
#1 /var/www/vhosts/staging.api-mydomain.com/src/public/test.php(8): Phalcon\Image\Adapter->text('Hello', 20, 20, 9, '#FFFFFF', 10, '/var/www/vhosts...')
#2 {main}
  thrown in phalcon/image/adapter/gd.zep on line 357

[Jeckerson]

To hotfix your problem, just do not specify $fontPath variable into text() method.

The problem is located in let s0 = (int) space[0];, which apparently can not be zero (according existing logic).

cphalcon/phalcon/Image/Adapter/Gd.zep

Lines 602 to 612 in a803581

	let space = imagettfbbox(size, 0, fontfile, text);
	if isset space[0] {
	let s0 = (int) space[0];
	let s1 = (int) space[1];
	let s4 = (int) space[4];
	let s5 = (int) space[5];
	}
	if unlikely (!s0 || !s1 || !s4 || !s5) {
	throw new Exception("Call to imagettfbbox() failed");