PHPMailer::isValidHost( string $host ): bool
- Source
wp-includes/PHPMailer/PHPMailer.php:4536
Description
IPv6 addresses must include [], e.g. [::1], not just ::1.
Compatibility
- WordPress
- core
- PHP
- 7.4–8.6-dev
- 6.7.7
- 6.8.8
- 6.9.7
- 7.0.4
- 7.1.0
Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.
Parameters
$hoststring- The host name or IP address to check
Return value
bool
Performance profile
How much work a call to PHPMailer::isValidHost() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Trivial
- Scaling
- Constant
- Instructions
- 4–32
- Plugin surface
- None
- Called by
- 0
Touches nothing outside its own arguments.
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 49.
Nothing here hands control to plugin code.
Nothing in core calls this; the cost is only what you spend yourself.
What one call costs · 2 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost PHPMailer::isValidHost() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 4–11 | none |
!empty($host) && is_string($host) && $host | 24–32 | filter_var() |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 49 | 4–32 | 8 | |
| 8.5 | 49 | 4–32 | 8 | |
| 8.4 | 49 | 4–32 | 8 | 17 fewer instructions than PHP 8.3 |
| 8.3 | 66 | 4–46 | 8 | |
| 8.2 | 66 | 4–46 | 8 | |
| 8.1 | 66 | 4–46 | 8 | |
| 7.4 | 66 | 4–46 | 8 |
An instruction is not a fixed amount of time, so a matching count is not necessarily the same speed; what it rules out is a difference in the work itself.
Source code
public static function isValidHost($host) { //Simple syntax limits if ( empty($host) || !is_string($host) || strlen($host) > 256 || !preg_match('/^([a-z\d.-]*|\[[a-f\d:]+\])$/i', $host) ) { return false; } //Looks like a bracketed IPv6 address if (strlen($host) > 2 && substr($host, 0, 1) === '[' && substr($host, -1, 1) === ']') { return filter_var(substr($host, 1, -1), FILTER_VALIDATE_IP, FILTER_FLAG_IPV6) !== false; } //If removing all the dots results in a numeric string, it must be an IPv4 address. //Need to check this first because otherwise things like `999.0.0.0` are considered valid host names if (is_numeric(str_replace('.', '', $host))) { //Is it a valid IPv4 address? return filter_var($host, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4) !== false; } //Is it a syntactically valid hostname (when embedded in a URL)? return filter_var('https://' . $host, FILTER_VALIDATE_URL) !== false; }Changelog
Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
About this page
- Parsed data
- Generated from the wordpress-develop 7.1.0 tag, from
src/wp-includes/PHPMailer/PHPMailer.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it. - Corrections
- Something wrong on this page? Report it and it gets fixed in the next regeneration.