WP_Http_Encoding::decompress( string $compressed, int $length = null ): string|false
- Since
- 2.8.0
- Source
wp-includes/class-wp-http-encoding.php:51
Description
Will attempt to decompress using the RFC 1950 standard, and if that fails then the RFC 1951 standard deflate will be attempted. Finally, the RFC 1952 standard gzip decode will be attempted. If all fail, then the original compressed string will be returned.
Compatibility
- WordPress
- since 2.8.0
- 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
$compressedstring- String to decompress.
$lengthintoptional- The optional length of the compressed data.Default:
null
Return value
string|false- Decompressed string on success, false on failure.
Performance profile
How much work a call to WP_Http_Encoding::decompress() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Trivial
- Scaling
- Constant
- Instructions
- 5–35
- Plugin surface
- None
- Called by
- 2
Touches nothing outside its own arguments.
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 40.
Nothing here hands control to plugin code.
2 places in core call this, so the cost is paid more often than your own code shows.
What one call costs · 5 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost WP_Http_Encoding::decompress() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
empty($compressed) | 5 | none |
!empty($compressed) && $decompressed !== false | 13 | gzinflate() |
!empty($compressed) | 19 | gzinflate(), ::compatible_gzinflate() |
!empty($compressed) | 27 | gzinflate(), ::compatible_gzinflate(), gzuncompress() |
!empty($compressed) && $decompressed === false | 35 | gzinflate(), ::compatible_gzinflate(), gzuncompress(), gzdecode() |
Across PHP versions
Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 40 instructions, 5–35 executed per call, 5 branches. The work does not change between versions.
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.
Uses · 1
- WP_Http_Encoding::compatible_gzinflate()Decompression of deflated string while staying compatible with the majority of servers.
Used by · 2
- WP_Http_Curl::request()Send a HTTP request to a URI using cURL extension.
- WP_Http_Streams::request()Send a HTTP request to a URI using PHP Streams.
Source code
public static function decompress( $compressed, $length = null ) { if ( empty( $compressed ) ) { return $compressed; } $decompressed = @gzinflate( $compressed ); if ( false !== $decompressed ) { return $decompressed; } $decompressed = self::compatible_gzinflate( $compressed ); if ( false !== $decompressed ) { return $decompressed; } $decompressed = @gzuncompress( $compressed ); if ( false !== $decompressed ) { return $decompressed; } if ( function_exists( 'gzdecode' ) ) { $decompressed = @gzdecode( $compressed ); if ( false !== $decompressed ) { return $decompressed; } } return $compressed; }Changelog
Introduced in 2.8.0. 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/class-wp-http-encoding.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.