This isn't my code, I found it and liked it so I'm saving it here. It's written by John-Mark Gurney from https://www.funkthat.com/~jmg/jmpc/
Version 1.1 now supports increasing the key using the fh_replace* functions. Previously it would simply return NULL when you tried to increase the key. It also improves performance slightly by only calling checkcons when we are about to use it, at extract, instead of calling it on every insert.
I have now fixed fh_union and it properly updates the minimum.
Thanks to Ryan Earl for pointing out that in fh_consolidate, it is VERY time consuming to constantly malloc/free an array of pointers. The array is small enough that simply reallocating when more pointers are needed is ok.
Thanks to Thomas Eschbach and Wolfgang Guenther who have pointed out bugs with my code. Wolfgang Guenther provided a fix which put in on the correct track for where the bug was. They have also provided a few test programs that exhibited other bugs which I have now integrated into my source so that you can easily regress test the library.
I have reciently completed a review of the code. I have made a number of improvements with a few minor interface changes. There is another improvement to the rh_replace* family of functions to help eliminate redundant code.
I'm still planning on writing a type safe memory allocator for use with the code instead of using malloc to hopefully improve performance slightly.