Save previous pointer automatically

[uroboro]

Removes the need to do so manually via dlsym calls. Also allows having multiple hooks on the same symbol.

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[grp]

I like this, but it does change the API for existing users. What's the motivation for the change?

[uroboro]

Besides the two reasons on the first comment, it was done to have a similar hooking interface as other projects like cydiasubstrate's MSHookFunction, rd_route's rd_route, mach_override's mach_override_ptr and substitute's substitute_hook_functions. The first three having an interface that accepts the target function symbol, its replacement and a pointer to save the previous address in. Using the address dlsym returns would skip all other hooks when calling the original implementation.

[grp]

Sounds good. I'm okay with breaking compatibility since fishhook is mostly for debugging anyway. :)

[grp]

Thanks!

[uroboro]

No problem!

[kastiglione]

🍰

[tirodkar]

The current podspec with the tag pointing to release 0.1 does not include this change. Could we have the podspec point to master or create a new release 0.2 with this change?