List all PHP extension api version no in zend_extensions.h

[c9s]

This PR provides a list of extension API no of each PHP release for extension developers to look up the extension versions

[KalleZ]

Minor detail here, I think they should be done at Zend/ level too, but as for the naming, then usually things in Zend/ are prefixed with ZEND_XXX, you can always make an alias of them with the name PHP_XXX from inside main/, for example main/php.h where the "PHP" counterpart of that value is defined.

[c9s]

Hi @KalleZ, do you mean to move the constants into main/php.h ?

[KalleZ]

Hi @c9s

I mean like, have the ones in Zend/ defined like:

#define ZEND_EXTENSION_API_NO_5_0                 220040412
#define ...

Then inside main/ we would have it like:

#define PHP_EXTENSION_API_NO_5_0 ZEND_EXTENSION_API_NO_5_0
#define ...

(Note I chacnged the names since it would sound 'wrong' otherwise)

This is usually the way many of the "cloned" API are named in regards to Zend/ and main/, cc @dstogov

[c9s]

makes sense, let me update the header files.

[c9s]

Hi @KalleZ ,

I only updated Zend/zend_extensions.h file because I think maintaining two constant list is too operose. One extension api version list shall be enough for extension development. :)

Thanks!

[wang-steven]

👍

[RickySu]

👍

[killtw]

👍

[Gasol]

👍

[nikic]

These look somewhat dangerous to me, since essentially the only thing you are doing here is exploiting that undefined macros are folded to 0 in #if and that #if ZEND_EXTENSION_API_NO < 0 is always false. If you tried using #if ZEND_EXTENSION_API_NO >= ZEND_EXTENSION_API_NO_5_5_X for example, it would not work correctly. The actual numbers you put into the macros are irrelevant.

So, if you want to add something like this, I'd drop the API nos and just define PHP_5_5_OR_NEWER macros, where usage is clear.

[c9s]

@nikic however if PHP_5_5_OR_NEWER is undefined, the #if is still false. And it won't work for php 5.5.x since the constants were defined 7.1.x.

I think this is just a re-useable constants & reference (or documented code) derived from ext/opcache/ZendAccelerator.h, the extension developers should be aware of the macro checking in their extension code.

[nikic]

@c9s You're right, that was a bad example. We could only start using this with 7_0_OR_NEWER etc, otherwise it wouldn't work.

So as this can only serve as documentation and cannot be used directly, maybe put the list of API nos in a comment instead?

[c9s]

@nikic I agree, the PR is updated.

[c9s]

@nikic one idea: maybe we can have a extension skeleton generator that generates some helpful macros & functions in the header files. (maybe in another PR)

[c9s]

Hi @smalyshev, This PR is not a quickfix, It's adding document for extension version constants.