random: Optimize data flow for the `generate` function of native engines (#13043)

Instead of returning the generated `uint64_t` and providing the size (i.e. the
number of bytes of the ge

random: Optimize data flow for the `generate` function of native engines (#13043)

Instead of returning the generated `uint64_t` and providing the size (i.e. the
number of bytes of the generated value) out-of-band via the
`last_generated_size` member of the `php_random_status` struct, the `generate`
function is now expected to return a new `php_random_result` struct containing
both the `size` and the `result`.

This has two benefits, one for the developer:

It's no longer possible to forget setting `last_generated_size` to the correct
value, because it now happens at the time of returning from the function.

and the other benefit is for performance:

The `php_random_result` struct will be returned as a register pair, thus the
`size` will be directly available without reloading it from main memory.

Checking a simplified version of `php_random_range64()` on Compiler Explorer
(“Godbolt”) with clang 17 shows a single change in the resulting assembly
showcasing the improvement (https://godbolt.org/z/G4WjdYxqx):

- add rbp, qword ptr [r14]
+ add rbp, rdx

Empirical testing confirms a measurable performance increase for the
`Randomizer::getBytes()` method:

<?php
$e = new Random\Engine\Xoshiro256StarStar(0);
$r = new Random\Randomizer($e);

var_dump(strlen($r->getBytes(100000000)));

goes from 250ms (before the change) to 220ms (after the change). While
generating 100 MB of random data certainly is not the most common use case, it
confirms the theoretical improvement in practice.

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Add ext/random Exception hierarchy (#9220)

* Add Random\Random{Error,Exception} and Random\BrokenRandomEngineError

* Throw BrokenRandomEngineError

* Throw RandomException o

Add ext/random Exception hierarchy (#9220)

* Add Random\Random{Error,Exception} and Random\BrokenRandomEngineError

* Throw BrokenRandomEngineError

* Throw RandomException on seeding failure

* Throw RandomException when CSPRNG fails

* Remove unused include from ext/random/engine_combinedlcg.c

* Remove unused include from ext/random/engine_secure.c

* Remove unused include from ext/random/random.c

* [ci skip] Add ext/random Exception hierarchy to NEWS

* [ci skip] Add the change of Exception for random_(int|bytes) to UPGRADING

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Remove `->last_unsafe` from php_random_status (#9132)

Whenever ->last_unsafe is set to `true` an exception has been thrown. Thus we
can replace the check for `->last_unsafe` with a check

Remove `->last_unsafe` from php_random_status (#9132)

Whenever ->last_unsafe is set to `true` an exception has been thrown. Thus we
can replace the check for `->last_unsafe` with a check for `EG(exception)`
which is a much more natural way to ommunicate an error up the chain.

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Improve error reporting in random extension (#9071)

* Use `php_random_bytes_throw()` in Secure engine's generate()

This exposes the underlying exception, improving debugging:

Improve error reporting in random extension (#9071)

* Use `php_random_bytes_throw()` in Secure engine's generate()

This exposes the underlying exception, improving debugging:

Fatal error: Uncaught Exception: Cannot open source device in php-src/test.php:5
Stack trace:
#0 php-src/test.php(5): Random\Engine\Secure->generate()
#1 {main}

Next RuntimeException: Random number generation failed in php-src/test.php:5
Stack trace:
#0 php-src/test.php(5): Random\Engine\Secure->generate()
#1 {main}
thrown in php-src/test.php on line 5

* Use `php_random_int_throw()` in Secure engine's range()

This exposes the underlying exception, improving debugging:

Exception: Cannot open source device in php-src/test.php:17
Stack trace:
#0 php-src/test.php(17): Random\Randomizer->getInt(1, 3)
#1 {main}

Next RuntimeException: Random number generation failed in php-src/test.php:17
Stack trace:
#0 php-src/test.php(17): Random\Randomizer->getInt(1, 3)
#1 {main}

* Throw exception when a user engine returns an empty string

This improves debugging, because the actual reason for the failure is available
as a previous Exception:

DomainException: The returned string must not be empty in php-src/test.php:17
Stack trace:
#0 php-src/test.php(17): Random\Randomizer->getBytes(123)
#1 {main}

Next RuntimeException: Random number generation failed in php-src/test.php:17
Stack trace:
#0 php-src/test.php(17): Random\Randomizer->getBytes(123)
#1 {main}

* Throw exception when the range selector fails to get acceptable numbers in 50 attempts

This improves debugging, because the actual reason for the failure is available
as a previous Exception:

RuntimeException: Failed to generate an acceptable random number in 50 attempts in php-src/test.php:17
Stack trace:
#0 php-src/test.php(17): Random\Randomizer->getInt(1, 3)
#1 {main}

Next RuntimeException: Random number generation failed in php-src/test.php:17
Stack trace:
#0 php-src/test.php(17): Random\Randomizer->getInt(1, 3)
#1 {main}

* Improve user_unsafe test

Select parameters for ->getInt() that will actually lead to unsafe behavior.

* Fix user_unsafe test

If an engine fails once it will be permanently poisoned by setting
`->last_unsafe`. This is undesirable for the test, because it skews the
results.

Fix this by creating a fresh engine for each "assertion".

* Remove duplication in user_unsafe.phpt

* Catch `Throwable` in user_unsafe.phpt

As we print the full stringified exception we implicitly assert the type of the
exception. No need to be overly specific in the catch block.

* Throw an error if an engine returns an empty string

* Throw an Error if range fails to find an acceptable number in 50 attempts

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[ci skip] Update EXTENSIONS and Author(s) in ext/random (#9074)

php.net account is better suited for this cases.

Fix segmentation fault in Randomizer::getBytes() if a user engine throws (#9055)

This fixes:

==374077== Use of uninitialised value of size 8
==374077== at 0x532B06: g

Fix segmentation fault in Randomizer::getBytes() if a user engine throws (#9055)

This fixes:

==374077== Use of uninitialised value of size 8
==374077== at 0x532B06: generate (engine_user.c:39)
==374077== by 0x533F71: zim_Random_Randomizer_getBytes (randomizer.c:152)
==374077== by 0x7F581D: ZEND_DO_FCALL_SPEC_RETVAL_USED_HANDLER (zend_vm_execute.h:1885)
==374077== by 0x8725BE: execute_ex (zend_vm_execute.h:55930)
==374077== by 0x877DB4: zend_execute (zend_vm_execute.h:60253)
==374077== by 0x7B0FD4: zend_execute_scripts (zend.c:1770)
==374077== by 0x6F1647: php_execute_script (main.c:2535)
==374077== by 0x937DA4: do_cli (php_cli.c:964)
==374077== by 0x938C3A: main (php_cli.c:1333)
==374077==
==374077== Invalid read of size 8
==374077== at 0x532B06: generate (engine_user.c:39)
==374077== by 0x533F71: zim_Random_Randomizer_getBytes (randomizer.c:152)
==374077== by 0x7F581D: ZEND_DO_FCALL_SPEC_RETVAL_USED_HANDLER (zend_vm_execute.h:1885)
==374077== by 0x8725BE: execute_ex (zend_vm_execute.h:55930)
==374077== by 0x877DB4: zend_execute (zend_vm_execute.h:60253)
==374077== by 0x7B0FD4: zend_execute_scripts (zend.c:1770)
==374077== by 0x6F1647: php_execute_script (main.c:2535)
==374077== by 0x937DA4: do_cli (php_cli.c:964)
==374077== by 0x938C3A: main (php_cli.c:1333)
==374077== Address 0x11 is not stack'd, malloc'd or (recently) free'd

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Implement Random Extension

https://wiki.php.net/rfc/rng_extension
https://wiki.php.net/rfc/random_extension_improvement