x509_crt.c does not respect alternate threading implementations about mbedtls

[pjbakker]

Fixed for next release

[mpg]

I'm afraid I disagree here :) The current code only work with pthreads indeed since it needs to initialize a global mutex. The following line will not compile with a non-pthread imlementation:

 static threading_mutex_t readdir_mutex = PTHREAD_MUTEX_INITIALIZER;

Some threading implementations do not provide similar static initializers. (Btw, the fact that using phtreads here is intentional is reflected in the function's documentation, see the warning.)

It is possible, however, to initialise global mutexes in threading_set_alt() but, in case it allocates some resources, then the user will have to call threading_free_alt(), a function that currently doesn't exist, or the resources will be lost. (OTOH, since you usually call threading_set_alt() only once, and the mutexes are most likely need till the end of the program anyway, it's not much of a leak.) (Paul, you can check the internal branch threading-1.4 (only one commit) for how I planned to handle global mutexes.)

So I thought it might be better to wait for the next API change to introduce global mutexes. But maybe it's also OK to make this change now but mention it clearly in the release notes?

[pjbakker]

@mpg You are totally right.. Missed that part..
Ok, so this one stays pthread-only for at least this 1.3 branch. Should be properly documented to prevent my mistaken fix in the future though!

[mpg]

This is fixed in the 2.0 branch (currently internal, hopefully release in the next few weeks).