This is liballoc, a memory allocator for hobby operating systems, originally written by Durand. According to the original page for liballoc it was released into the public domain, but the copy I have contains the 3 clause BSD license.

liballoc.c/h are the original release of liballoc taken from the spoon tarball while liballoc_1_1.c/h are later versions found by detective work using Google.

There are 4 functions which you need to implement on your system:

int   liballoc_lock();
int   liballoc_unlock();
void* liballoc_alloc(int);
int   liballoc_free(void*,int);

1. Have a look at liballoc.h for information about what each function is supposed to do.

2. Have a look at linux.c for an example of how to implement the library on linux.

NOTE: There are two ways to build the library:

1) Compile the library with a new system file. For example, I've
   left linux.c with the default distribution. It gets compiled
   directly into the liballoc_linux.so file.

2) Implement the functions in your application and then just
   link against the default liballoc.so library when you compile
   your app.

You can simply type: "make linux" to build the linux shared library. Thereafter, you can link it directly into your applications during build or afterwards by export the LD_PRELOAD environment variable.

To run bash with the library, for example:

LD_PRELOAD=/full/path/to/liballoc.so bash

The above command will pre-link the library into the application, essentially replacing the default malloc/free calls at runtime. It's quite cool.

Originally by: Durand Miller