diff options
Diffstat (limited to 'Documentation/technical')
| -rw-r--r-- | Documentation/technical/api-merge.txt | 73 | ||||
| -rw-r--r-- | Documentation/technical/api-parse-options.txt | 20 | ||||
| -rw-r--r-- | Documentation/technical/api-run-command.txt | 5 | ||||
| -rw-r--r-- | Documentation/technical/api-sigchain.txt | 41 | ||||
| -rw-r--r-- | Documentation/technical/api-string-list.txt | 10 | ||||
| -rw-r--r-- | Documentation/technical/api-tree-walking.txt | 2 | ||||
| -rw-r--r-- | Documentation/technical/protocol-capabilities.txt | 2 |
7 files changed, 143 insertions, 10 deletions
diff --git a/Documentation/technical/api-merge.txt b/Documentation/technical/api-merge.txt new file mode 100644 index 000000000..a7e050bb7 --- /dev/null +++ b/Documentation/technical/api-merge.txt @@ -0,0 +1,73 @@ +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. + +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. + +The caller: + +1. allocates an mmbuffer_t variable for the result; +2. allocates and fills variables with the file's original content + and two modified versions (using `read_mmfile`, for example); +3. calls ll_merge(); +4. reads the output from result_buf.ptr and result_buf.size; +5. releases buffers when finished (free(ancestor.ptr); free(ours.ptr); + free(theirs.ptr); free(result_buf.ptr);). + +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. + +The `flag` parameter is a bitfield: + + - The `LL_OPT_VIRTUAL_ANCESTOR` bit indicates whether this is an + internal merge to consolidate ancestors for a recursive merge. + + - The `LL_OPT_FAVOR_MASK` bits allow local conflicts to be automatically + resolved in favor of one side or the other (as in 'git merge-file' + `--ours`/`--theirs`/`--union`). + They can be populated by `create_ll_flag`, whose argument can be + `XDL_MERGE_FAVOR_OURS`, `XDL_MERGE_FAVOR_THEIRS`, or + `XDL_MERGE_FAVOR_UNION`. + +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 50f9e9ac1..c5d141cd6 100644 --- a/Documentation/technical/api-parse-options.txt +++ b/Documentation/technical/api-parse-options.txt @@ -115,6 +115,9 @@ There are some macros to easily define options: `OPT__ABBREV(&int_var)`:: Add `\--abbrev[=<n>]`. +`OPT__COLOR(&int_var, description)`:: + Add `\--color[=<when>]` and `--no-color`. + `OPT__DRY_RUN(&int_var)`:: Add `-n, \--dry-run`. @@ -183,13 +186,22 @@ There are some macros to easily define options: arguments. Short options that happen to be digits take precedence over it. +`OPT_COLOR_FLAG(short, long, &int_var, description)`:: + Introduce an option that takes an optional argument that can + have one of three values: "always", "never", or "auto". If the + argument is not given, it defaults to "always". The `--no-` form + works like `--long=never`; it cannot take an argument. If + "always", set `int_var` to 1; if "never", set `int_var` to 0; if + "auto", set `int_var` to 1 if stdout is a tty or a pager, + 0 otherwise. + 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), @@ -216,10 +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-run-command.txt b/Documentation/technical/api-run-command.txt index 44876fa70..f18b4f481 100644 --- a/Documentation/technical/api-run-command.txt +++ b/Documentation/technical/api-run-command.txt @@ -231,8 +231,9 @@ The function pointer in .proc has the following signature: There are serious restrictions on what the asynchronous function can do -because this facility is implemented by a pipe to a forked process on -UNIX, but by a thread in the same address space on Windows: +because this facility is implemented by a thread in the same address +space on most platforms (when pthreads is available), but by a pipe to +a forked process otherwise: . It cannot change the program's state (global variables, environment, etc.) in a way that the caller notices; in other words, .in and .out diff --git a/Documentation/technical/api-sigchain.txt b/Documentation/technical/api-sigchain.txt new file mode 100644 index 000000000..535cdff16 --- /dev/null +++ b/Documentation/technical/api-sigchain.txt @@ -0,0 +1,41 @@ +sigchain API +============ + +Code often wants to set a signal handler to clean up temporary files or +other work-in-progress when we die unexpectedly. For multiple pieces of +code to do this without conflicting, each piece of code must remember +the old value of the handler and restore it either when: + + 1. The work-in-progress is finished, and the handler is no longer + necessary. The handler should revert to the original behavior + (either another handler, SIG_DFL, or SIG_IGN). + + 2. The signal is received. We should then do our cleanup, then chain + to the next handler (or die if it is SIG_DFL). + +Sigchain is a tiny library for keeping a stack of handlers. Your handler +and installation code should look something like: + +------------------------------------------ + void clean_foo_on_signal(int sig) + { + clean_foo(); + sigchain_pop(sig); + raise(sig); + } + + void other_func() + { + sigchain_push_common(clean_foo_on_signal); + mess_up_foo(); + clean_foo(); + } +------------------------------------------ + +Handlers are given the typdef of sigchain_fun. This is the same type +that is given to signal() or sigaction(). It is perfectly reasonable to +push SIG_DFL or SIG_IGN onto the stack. + +You can sigchain_push and sigchain_pop individual signals. For +convenience, sigchain_push_common will push the handler onto the stack +for many common signals. diff --git a/Documentation/technical/api-string-list.txt b/Documentation/technical/api-string-list.txt index 293bb15d2..3f575bdcf 100644 --- a/Documentation/technical/api-string-list.txt +++ b/Documentation/technical/api-string-list.txt @@ -38,8 +38,8 @@ struct string_list list; int i; memset(&list, 0, sizeof(struct string_list)); -string_list_append("foo", &list); -string_list_append("bar", &list); +string_list_append(&list, "foo"); +string_list_append(&list, "bar"); for (i = 0; i < list.nr; i++) printf("%s\n", list.items[i].string) ---- @@ -104,8 +104,12 @@ write `string_list_insert(...)->util = ...;`. `unsorted_string_list_has_string`:: It's like `string_list_has_string()` but for unsorted lists. + +`unsorted_string_list_lookup`:: + + It's like `string_list_lookup()` but for unsorted lists. + -This function needs to look through all items, as opposed to its +The above two functions need to look through all items, as opposed to their counterpart for sorted lists, which performs a binary search. Data structures diff --git a/Documentation/technical/api-tree-walking.txt b/Documentation/technical/api-tree-walking.txt index 55b728632..14af37c3f 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 ------------ diff --git a/Documentation/technical/protocol-capabilities.txt b/Documentation/technical/protocol-capabilities.txt index fd1a59314..b15517fa0 100644 --- a/Documentation/technical/protocol-capabilities.txt +++ b/Documentation/technical/protocol-capabilities.txt @@ -119,7 +119,7 @@ both. ofs-delta --------- -Server can send, and client understand PACKv2 with delta refering to +Server can send, and client understand PACKv2 with delta referring to its base by position in pack rather than by an obj-id. That is, they can send/read OBJ_OFS_DELTA (aka type 6) in a packfile. |