diff options
Diffstat (limited to 'Documentation/technical')
-rw-r--r-- | Documentation/technical/api-merge.txt | 104 | ||||
-rw-r--r-- | Documentation/technical/api-parse-options.txt | 8 | ||||
-rw-r--r-- | Documentation/technical/api-tree-walking.txt | 2 |
3 files changed, 110 insertions, 4 deletions
diff --git a/Documentation/technical/api-merge.txt b/Documentation/technical/api-merge.txt new file mode 100644 index 0000000000..9dc1bed768 --- /dev/null +++ b/Documentation/technical/api-merge.txt @@ -0,0 +1,104 @@ +merge API +========= + +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` + +This describes the set of options the calling program wants to affect +the operation of a low-level (single file) merge. Some options: + +`virtual_ancestor`:: + Behave as though this were part of a merge between common + ancestors in a recursive merge. + If a helper program is specified by the + `[merge "<driver>"] recursive` configuration, it will + be used (see linkgit:gitattributes[5]). + +`variant`:: + Resolve local conflicts automatically in favor + of one side or the other (as in 'git merge-file' + `--ours`/`--theirs`/`--union`). Can be `0`, + `XDL_MERGE_FAVOR_OURS`, `XDL_MERGE_FAVOR_THEIRS`, or + `XDL_MERGE_FAVOR_UNION`. + +`renormalize`:: + Resmudge and clean the "base", "theirs" and "ours" files + before merging. Use this when the merge is likely to have + overlapped with a change in smudge/clean or end-of-line + normalization rules. + +Low-level (single file) merge +----------------------------- + +`ll_merge`:: + + Perform a three-way single-file merge in core. This is + a thin wrapper around `xdl_merge` that takes the path and + any merge backend specified in `.gitattributes` or + `.git/info/attributes` into account. Returns 0 for a + clean merge. + +Calling sequence: + +* Prepare a `struct ll_merge_options` to record options. + If you have no special requests, skip this and pass `NULL` + as the `opts` parameter to use the default options. + +* Allocate an mmbuffer_t variable for the result. + +* Allocate and fill variables with the file's original content + and two modified versions (using `read_mmfile`, for example). + +* Call `ll_merge()`. + +* Read the merged content from `result_buf.ptr` and `result_buf.size`. + +* Release buffers when finished. A simple + `free(ancestor.ptr); free(ours.ptr); free(theirs.ptr); + free(result_buf.ptr);` will do. + +If the modifications do not merge cleanly, `ll_merge` will return a +nonzero value and `result_buf` will generally include a description of +the conflict bracketed by markers such as the traditional `<<<<<<<` +and `>>>>>>>`. + +The `ancestor_label`, `our_label`, and `their_label` parameters are +used to label the different sides of a conflict if the merge driver +supports this. + +Everything else +--------------- + +Talk about <merge-recursive.h> and merge_file(): + + - merge_trees() to merge with rename detection + - merge_recursive() for ancestor consolidation + - try_merge_command() for other strategies + - conflict format + - merge options + +(Daniel, Miklos, Stephan, JC) diff --git a/Documentation/technical/api-parse-options.txt b/Documentation/technical/api-parse-options.txt index 312e3b2e2b..c5d141cd63 100644 --- a/Documentation/technical/api-parse-options.txt +++ b/Documentation/technical/api-parse-options.txt @@ -201,7 +201,7 @@ The last element of the array must be `OPT_END()`. If not stated otherwise, interpret the arguments as follows: * `short` is a character for the short option - (e.g. `\'e\'` for `-e`, use `0` to omit), + (e.g. `{apostrophe}e{apostrophe}` for `-e`, use `0` to omit), * `long` is a string for the long option (e.g. `"example"` for `\--example`, use `NULL` to omit), @@ -228,10 +228,10 @@ The function must be defined in this form: The callback mechanism is as follows: * Inside `func`, the only interesting member of the structure - given by `opt` is the void pointer `opt->value`. - `\*opt->value` will be the value that is saved into `var`, if you + given by `opt` is the void pointer `opt\->value`. + `\*opt\->value` will be the value that is saved into `var`, if you use `OPT_CALLBACK()`. - For example, do `*(unsigned long *)opt->value = 42;` to get 42 + For example, do `*(unsigned long *)opt\->value = 42;` to get 42 into an `unsigned long` variable. * Return value `0` indicates success and non-zero return diff --git a/Documentation/technical/api-tree-walking.txt b/Documentation/technical/api-tree-walking.txt index 55b728632c..14af37c3f1 100644 --- a/Documentation/technical/api-tree-walking.txt +++ b/Documentation/technical/api-tree-walking.txt @@ -42,6 +42,8 @@ information. * `data` can be anything the `fn` callback would want to use. +* `show_all_errors` tells whether to stop at the first error or not. + Initializing ------------ |