CODESTYLE

Don't use a common prefix for source files. Tab completion is good.
Library files should go in a top level directory, so that it can be compiled easily.

config.h sometimes includes things inline, and should be the first in any file that includes it.
Next, include the header file for the source file, so that all public headers are self-contained.
Next, include any libc headers.
Next, include any non-standard library headers (i.e. libheis)
Finally, include any private headers

Use GNU-style indentation.
Functions are defined with the function return type and function name on separate lines, while declaration is one line, so that grep ^function-name only returns the definition.
Two blank lines between function definitions.

Never use explicit checks for true or false. Always use explicit checks for non-boolean int values (i.e. implicit check for an int that only returns 0 or 1 is fine).