use mergesort(3) instead of qsort(3) in patience diff Fixes test failures on OpenBSD due to unstable results of qsort if two or more elements are equal. Add a compat copy of OpenBSD mergesort(3) for Linux.

check for allocation failure in diff_atoms_mark_unique_in_both_by_qsort()

wrap a comment that had overlong lines

patience: fix uninitialized rc in diff_atoms_qsort_compar

move patience data out of struct diff_atom Now allocating patience specific data only when patience is going to be used. This may allow using forward-Myers more often, since the state size per line is significantly smaller. Patience instead allocates an array, puts it in the current diff_data, and also place a pointer of the current diff_data in the root diff_data (since each atom points to the root diff_data).

patience: use qsort to optimize finding unique lines

move headers from include/diff/ to include/; makes things easier for consumers

repair DEBUG build

move some definitions from the public diff_main.h to an internal header file

rename 'debug.h' to 'diff_debug.h'

patience: error handling from diff_atoms_same()

add diff_atom_cmp() and error handling to diff_atom_same()

avoid include statements in header files; make each .c pull in what's needed

replace enum diff_rc errors with plain errno values

move 'struct range' and related functions into the diff_ namespace no functional change

fix wrong assignment in diff_atoms_swallow_identical_neighbors; ok neels

KNF: use max 80 columns

KNF: function declaration return types on separate line

Kill unused variables

Fix macro diff_atom_*idx return value types The macros sometimes returned unsigned int (atoms.len) or long int ((ATOM) - head). Make that always unsigned int, with some range checks against negative values.

patience: reduce sections by swallowing identical lines before LCS

initial commit