The merge API helps a program to reconcile two competing sets of improvements to some files (e.g., unregistered changes from the work tree versus changes involved in switching to a new branch), reporting conflicts if found. The library called through this API is responsible for a few things.

  • determining which trees to merge (recursive ancestor consolidation);

  • lining up corresponding files in the trees to be merged (rename detection, subtree shifting), reporting edge cases like add/add and rename/rename conflicts to the user;

  • performing a three-way merge of corresponding files, taking path-specific merge drivers (specified in .gitattributes) into account.

Data structures

  • mmbuffer_t, mmfile_t

These store data usable for use by the xdiff backend, for writing and for reading, respectively. See xdiff/xdiff.h for the definitions and diff.c for examples.

  • struct ll_merge_options

Check merge-ll.h for details.

Low-level (single file) merge

Check merge-ll.h for details.