PHP gmp_import() Function

As of my last update in September 2021, PHP’s GMP (GNU Multiple Precision) extension includes the gmp_import() function. The gmp_import() function is used to import binary data into a GMP number.

Here’s the syntax of the gmp_import() function:

GMP gmp_import ( string $data [, int $word_size = 1 [, int $options = GMP_MSW_FIRST | GMP_NATIVE_ENDIAN ]] )

Parameters:

• $data: The binary data to be imported into a GMP number.
• $word_size: (Optional) The number of bytes per word. The default value is 1.
• $options: (Optional) A bitmask of options. The default value is GMP_MSW_FIRST | GMP_NATIVE_ENDIAN.

Return value:

• The gmp_import() function returns a GMP number representing the binary data.

Example:

$data = "\x12\x34\x56\x78";
$gmpNumber = gmp_import($data);

echo gmp_strval($gmpNumber); // Output: 131176846506

In this example, the gmp_import() function is used to convert the binary data represented by the string "\x12\x34\x56\x78" into a GMP number. The resulting GMP number is 131176846506.

The gmp_import() function is useful when you need to work with large binary data, such as cryptographic keys or hash values, as GMP provides arbitrary precision arithmetic.

The $word_size parameter allows you to specify the number of bytes per word when importing the data. The default value of 1 means that each byte of the data is treated as a separate word. You can increase the $word_size value to process multiple bytes at a time, which can improve performance for large datasets.

The $options parameter allows you to set options for the importing process, such as the byte order of the data (GMP_NATIVE_ENDIAN or GMP_LSW_FIRST), but the default values should work for most cases.

Please note that the GMP extension needs to be enabled in your PHP configuration to use this function. Additionally, the availability of functions may change in newer PHP versions, so always refer to the PHP manual for the specific version you are using.