Allow to customize fz_store_size in Java bindings

[max-kammerer]

No description provided.

[robinwatts]

So, if I build a MuPDF library with FZ_STORE_DEFAULT_SIZE_IN_MB defined, it'll make no difference to anyone that uses that library, as they won't have that defined when they include context.h, so they'll get the default value.

If people want to use a different value for the store, they should state it explicitly. That is the purpose of this field after all!

If your intent is to allow runtime definition of the store size used in the java bindings, then that's not unreasonable, but I don't think you need the include/mupdf/fitz/context.h changes for that.

[max-kammerer]

Hi @robinwatts! Yes, my main case is to allow runtime definitions of the store size in java bindings and it's covered by change in context.c. But I can use this scenario only with Android 5+, as Android allows to set env variables on runtime just starting from Android 5.
For Android 4.x devices I need another way to override default value and I came up with static solution passing FZ_STORE_DEFAULT_SIZE_IN_MB during compilation as I build mupdf library during application build.

[robinwatts]

Leave the definition of FZ_STORE_DEFAULT alone.

In the Java code:

#ifdef FZ_JAVA_STORE_SIZE
size_t fz_store_size = FZ_JAVA_STORE_SIZE;
#else
size_t fz_store_size = FZ_STORE_DEFAULT;
#endif
char *env_fz_store_size = getenv("FZ_JAVA_STORE_SIZE");
if (env_fz_store_size)
fz_store_size = atol(env_fz_store_size);
base_context = fz_new_context(NULL, &locks, fz_store_size);

That way you can predefine FZ_JAVA_STORE_SIZE when you build the java bindings, or you can use the same environment variable. Don't mess around with specifying it in MB.

[max-kammerer]

@robinwatts Thank you! Updated!