random: Clean up seeding API (#13540)

* random: Expose xoshiro256**'s seeding functions

* random: Expose pcgoneseq128xslrr64's seeding functions

* random: Expose Mt19937's

random: Clean up seeding API (#13540)

* random: Expose xoshiro256**'s seeding functions

* random: Expose pcgoneseq128xslrr64's seeding functions

* random: Expose Mt19937's seeding functions

* random: Expose CombinedLCG's seeding functions

* random: Call php_random_mt19937_seed32 to seed the global Mt19937

This avoids the function pointer indirection and improves type safety.

* random: NULL the generic seeding function

Different engines work quite differently, it is not useful to attempt to seed
them in a generic way using a 64 bit integer. As an example Mt19937 completely
ignores the upper 32 bits.

* random: Remove the `seed` member from `php_random_algo`

See the explanation in the previous commit for the reasoning. This member is
unused since the previous commit and was not consistently available even before
that (specifically for the Secure engine).

* UPGRADING.INTERNALS

* random: Remove useless cast in `php_mt_srand()`

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random: Adjust `status` to `state` (#13521)

* random: Rename `status` local to `state`

* random: Rename `php_random_algo_with_state`'s `status` member to `state`

random: Pass algorithm and state together as `php_random_algo_with_state` (#13350)

* random: Remove `php_random_status`

Since 162e1dce9870168cb8c65c013f2b5a510b6536b1, the `php_rand

random: Pass algorithm and state together as `php_random_algo_with_state` (#13350)

* random: Remove `php_random_status`

Since 162e1dce9870168cb8c65c013f2b5a510b6536b1, the `php_random_status` struct
contains just a single `void*`, resulting in needless indirection when
accessing the engine state and thus decreasing readability because of the
additional non-meaningful `->state` references / the local helper variables.

There is also a small, but measurable performance benefit:

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

for ($i = 0; $i < 15; $i++)
var_dump(strlen($r->getBytes(100000000)));

goes from roughly 3.85s down to 3.60s.

The names of the `status` variables have not yet been touched to keep the diff
small. They will be renamed to the more appropriate `state` in a follow-up
cleanup commit.

* Introduce `php_random_algo_with_state`

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random: Do not hardcode the target type when invoking the CSPRNG (#13308)

Instead derive the number of bytes to retrieve from the variable that is being
filled.

random: Move CSPRNG API into php_random_csprng.h (#13290)

This allows consumers of just the CSPRNG to include a much smaller header. It
also allows to verify at a glance whether a source

random: Move CSPRNG API into php_random_csprng.h (#13290)

This allows consumers of just the CSPRNG to include a much smaller header. It
also allows to verify at a glance whether a source file might use non-secure
randomness.

This commit includes the new header wherever the CSPRNG is used, possibly
replacing the inclusion of php_random.h if nothing else is used, but also
includes it in the main php_random.h header for compatibility.

Somewhat related to 45f8cfaf104f504340b0073b9736bb50a88d70a1,
2b30f18708b4f73d2c1d29d3a92a606ebdc5ac4c, and
b14dd85dca3b67a5462f5ed9b6aa0dc22beb615c.

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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.

Implement Random Extension

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