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|
/*
* Copyright (C) the libgit2 contributors. All rights reserved.
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
#ifndef INCLUDE_git_diff_h__
#define INCLUDE_git_diff_h__
#include "common.h"
#include "types.h"
#include "oid.h"
#include "tree.h"
#include "refs.h"
/**
* @file git2/diff.h
* @brief Git tree and file differencing routines.
*
* Overview
* --------
*
* Calculating diffs is generally done in two phases: building a diff list
* then traversing the diff list. This makes is easier to share logic
* across the various types of diffs (tree vs tree, workdir vs index, etc.),
* and also allows you to insert optional diff list post-processing phases,
* such as rename detected, in between the steps. When you are done with a
* diff list object, it must be freed.
*
* Terminology
* -----------
*
* To understand the diff APIs, you should know the following terms:
*
* - A `diff` or `diff list` represents the cumulative list of differences
* between two snapshots of a repository (possibly filtered by a set of
* file name patterns). This is the `git_diff_list` object.
* - A `delta` is a file pair with an old and new revision. The old version
* may be absent if the file was just created and the new version may be
* absent if the file was deleted. A diff is mostly just a list of deltas.
* - A `binary` file / delta is a file (or pair) for which no text diffs
* should be generated. A diff list can contain delta entries that are
* binary, but no diff content will be output for those files. There is
* a base heuristic for binary detection and you can further tune the
* behavior with git attributes or diff flags and option settings.
* - A `hunk` is a span of modified lines in a delta along with some stable
* surrounding context. You can configure the amount of context and other
* properties of how hunks are generated. Each hunk also comes with a
* header that described where it starts and ends in both the old and new
* versions in the delta.
* - A `line` is a range of characters inside a hunk. It could be a context
* line (i.e. in both old and new versions), an added line (i.e. only in
* the new version), or a removed line (i.e. only in the old version).
* Unfortunately, we don't know anything about the encoding of data in the
* file being diffed, so we cannot tell you much about the line content.
* Line data will not be NUL-byte terminated, however, because it will be
* just a span of bytes inside the larger file.
*
* @ingroup Git
* @{
*/
GIT_BEGIN_DECL
/**
* Flags for diff options. A combination of these flags can be passed
* in via the `flags` value in the `git_diff_options`.
*/
typedef enum {
/** Normal diff, the default */
GIT_DIFF_NORMAL = 0,
/** Reverse the sides of the diff */
GIT_DIFF_REVERSE = (1 << 0),
/** Treat all files as text, disabling binary attributes & detection */
GIT_DIFF_FORCE_TEXT = (1 << 1),
/** Ignore all whitespace */
GIT_DIFF_IGNORE_WHITESPACE = (1 << 2),
/** Ignore changes in amount of whitespace */
GIT_DIFF_IGNORE_WHITESPACE_CHANGE = (1 << 3),
/** Ignore whitespace at end of line */
GIT_DIFF_IGNORE_WHITESPACE_EOL = (1 << 4),
/** Exclude submodules from the diff completely */
GIT_DIFF_IGNORE_SUBMODULES = (1 << 5),
/** Use the "patience diff" algorithm (currently unimplemented) */
GIT_DIFF_PATIENCE = (1 << 6),
/** Include ignored files in the diff list */
GIT_DIFF_INCLUDE_IGNORED = (1 << 7),
/** Include untracked files in the diff list */
GIT_DIFF_INCLUDE_UNTRACKED = (1 << 8),
/** Include unmodified files in the diff list */
GIT_DIFF_INCLUDE_UNMODIFIED = (1 << 9),
/** Even with GIT_DIFF_INCLUDE_UNTRACKED, an entire untracked directory
* will be marked with only a single entry in the diff list; this flag
* adds all files under the directory as UNTRACKED entries, too.
*/
GIT_DIFF_RECURSE_UNTRACKED_DIRS = (1 << 10),
/** If the pathspec is set in the diff options, this flags means to
* apply it as an exact match instead of as an fnmatch pattern.
*/
GIT_DIFF_DISABLE_PATHSPEC_MATCH = (1 << 11),
/** Use case insensitive filename comparisons */
GIT_DIFF_DELTAS_ARE_ICASE = (1 << 12),
/** When generating patch text, include the content of untracked files */
GIT_DIFF_INCLUDE_UNTRACKED_CONTENT = (1 << 13),
/** Disable updating of the `binary` flag in delta records. This is
* useful when iterating over a diff if you don't need hunk and data
* callbacks and want to avoid having to load file completely.
*/
GIT_DIFF_SKIP_BINARY_CHECK = (1 << 14),
/** Normally, a type change between files will be converted into a
* DELETED record for the old and an ADDED record for the new; this
* options enabled the generation of TYPECHANGE delta records.
*/
GIT_DIFF_INCLUDE_TYPECHANGE = (1 << 15),
/** Even with GIT_DIFF_INCLUDE_TYPECHANGE, blob->tree changes still
* generally show as a DELETED blob. This flag tries to correctly
* label blob->tree transitions as TYPECHANGE records with new_file's
* mode set to tree. Note: the tree SHA will not be available.
*/
GIT_DIFF_INCLUDE_TYPECHANGE_TREES = (1 << 16),
/** Ignore file mode changes */
GIT_DIFF_IGNORE_FILEMODE = (1 << 17),
/** Even with GIT_DIFF_INCLUDE_IGNORED, an entire ignored directory
* will be marked with only a single entry in the diff list; this flag
* adds all files under the directory as IGNORED entries, too.
*/
GIT_DIFF_RECURSE_IGNORED_DIRS = (1 << 18),
/** Core Git scans inside untracked directories, labeling them IGNORED
* if they are empty or only contain ignored files; a directory is
* consider UNTRACKED only if it has an actual untracked file in it.
* This scan is extra work for a case you often don't care about. This
* flag makes libgit2 immediately label an untracked directory as
* UNTRACKED without looking insde it (which differs from core Git).
* Of course, ignore rules are still checked for the directory itself.
*/
GIT_DIFF_FAST_UNTRACKED_DIRS = (1 << 19),
} git_diff_option_t;
/**
* The diff list object that contains all individual file deltas.
*
* This is an opaque structure which will be allocated by one of the diff
* generator functions below (such as `git_diff_tree_to_tree`). You are
* responsible for releasing the object memory when done, using the
* `git_diff_list_free()` function.
*/
typedef struct git_diff_list git_diff_list;
/**
* Flags for the delta object and the file objects on each side.
*
* These flags are used for both the `flags` value of the `git_diff_delta`
* and the flags for the `git_diff_file` objects representing the old and
* new sides of the delta. Values outside of this public range should be
* considered reserved for internal or future use.
*/
typedef enum {
GIT_DIFF_FLAG_BINARY = (1 << 0), /** file(s) treated as binary data */
GIT_DIFF_FLAG_NOT_BINARY = (1 << 1), /** file(s) treated as text data */
GIT_DIFF_FLAG_VALID_OID = (1 << 2), /** `oid` value is known correct */
} git_diff_flag_t;
/**
* What type of change is described by a git_diff_delta?
*
* `GIT_DELTA_RENAMED` and `GIT_DELTA_COPIED` will only show up if you run
* `git_diff_find_similar()` on the diff list object.
*
* `GIT_DELTA_TYPECHANGE` only shows up given `GIT_DIFF_INCLUDE_TYPECHANGE`
* in the option flags (otherwise type changes will be split into ADDED /
* DELETED pairs).
*/
typedef enum {
GIT_DELTA_UNMODIFIED = 0, /** no changes */
GIT_DELTA_ADDED = 1, /** entry does not exist in old version */
GIT_DELTA_DELETED = 2, /** entry does not exist in new version */
GIT_DELTA_MODIFIED = 3, /** entry content changed between old and new */
GIT_DELTA_RENAMED = 4, /** entry was renamed between old and new */
GIT_DELTA_COPIED = 5, /** entry was copied from another old entry */
GIT_DELTA_IGNORED = 6, /** entry is ignored item in workdir */
GIT_DELTA_UNTRACKED = 7, /** entry is untracked item in workdir */
GIT_DELTA_TYPECHANGE = 8, /** type of entry changed between old and new */
} git_delta_t;
/**
* Description of one side of a diff entry.
*
* Although this is called a "file", it may actually represent a file, a
* symbolic link, a submodule commit id, or even a tree (although that only
* if you are tracking type changes or ignored/untracked directories).
*
* The `oid` is the `git_oid` of the item. If the entry represents an
* absent side of a diff (e.g. the `old_file` of a `GIT_DELTA_ADDED` delta),
* then the oid will be zeroes.
*
* `path` is the NUL-terminated path to the entry relative to the working
* directory of the repository.
*
* `size` is the size of the entry in bytes.
*
* `flags` is a combination of the `git_diff_flag_t` types
*
* `mode` is, roughly, the stat() `st_mode` value for the item. This will
* be restricted to one of the `git_filemode_t` values.
*/
typedef struct {
git_oid oid;
const char *path;
git_off_t size;
uint32_t flags;
uint16_t mode;
} git_diff_file;
/**
* Description of changes to one entry.
*
* When iterating over a diff list object, this will be passed to most
* callback functions and you can use the contents to understand exactly
* what has changed.
*
* The `old_file` represents the "from" side of the diff and the `new_file`
* represents to "to" side of the diff. What those means depend on the
* function that was used to generate the diff and will be documented below.
* You can also use the `GIT_DIFF_REVERSE` flag to flip it around.
*
* Although the two sides of the delta are named "old_file" and "new_file",
* they actually may correspond to entries that represent a file, a symbolic
* link, a submodule commit id, or even a tree (if you are tracking type
* changes or ignored/untracked directories).
*
* Under some circumstances, in the name of efficiency, not all fields will
* be filled in, but we generally try to fill in as much as possible. One
* example is that the "flags" field may not have either the `BINARY` or the
* `NOT_BINARY` flag set to avoid examining file contents if you do not pass
* in hunk and/or line callbacks to the diff foreach iteration function. It
* will just use the git attributes for those files.
*/
typedef struct {
git_diff_file old_file;
git_diff_file new_file;
git_delta_t status;
uint32_t similarity; /**< for RENAMED and COPIED, value 0-100 */
uint32_t flags;
} git_diff_delta;
/**
* Diff notification callback function.
*
* The callback will be called for each file, just before the `git_delta_t`
* gets inserted into the diff list.
*
* When the callback:
* - returns < 0, the diff process will be aborted.
* - returns > 0, the delta will not be inserted into the diff list, but the
* diff process continues.
* - returns 0, the delta is inserted into the diff list, and the diff process
* continues.
*/
typedef int (*git_diff_notify_cb)(
const git_diff_list *diff_so_far,
const git_diff_delta *delta_to_add,
const char *matched_pathspec,
void *payload);
/**
* Structure describing options about how the diff should be executed.
*
* Setting all values of the structure to zero will yield the default
* values. Similarly, passing NULL for the options structure will
* give the defaults. The default values are marked below.
*
* - `flags` is a combination of the `git_diff_option_t` values above
* - `context_lines` is the number of unchanged lines that define the
* boundary of a hunk (and to display before and after)
* - `interhunk_lines` is the maximum number of unchanged lines between
* hunk boundaries before the hunks will be merged into a one.
* - `old_prefix` is the virtual "directory" to prefix to old file names
* in hunk headers (default "a")
* - `new_prefix` is the virtual "directory" to prefix to new file names
* in hunk headers (default "b")
* - `pathspec` is an array of paths / fnmatch patterns to constrain diff
* - `max_size` is a file size (in bytes) above which a blob will be marked
* as binary automatically; pass a negative value to disable.
* - `notify_cb` is an optional callback function, notifying the consumer of
* which files are being examined as the diff is generated
* - `notify_payload` is the payload data to pass to the `notify_cb` function
*/
typedef struct {
unsigned int version; /**< version for the struct */
uint32_t flags; /**< defaults to GIT_DIFF_NORMAL */
uint16_t context_lines; /**< defaults to 3 */
uint16_t interhunk_lines; /**< defaults to 0 */
const char *old_prefix; /**< defaults to "a" */
const char *new_prefix; /**< defaults to "b" */
git_strarray pathspec; /**< defaults to include all paths */
git_off_t max_size; /**< defaults to 512MB */
git_diff_notify_cb notify_cb;
void *notify_payload;
} git_diff_options;
#define GIT_DIFF_OPTIONS_VERSION 1
#define GIT_DIFF_OPTIONS_INIT {GIT_DIFF_OPTIONS_VERSION, GIT_DIFF_NORMAL, 3}
/**
* When iterating over a diff, callback that will be made per file.
*
* @param delta A pointer to the delta data for the file
* @param progress Goes from 0 to 1 over the diff list
* @param payload User-specified pointer from foreach function
*/
typedef int (*git_diff_file_cb)(
const git_diff_delta *delta,
float progress,
void *payload);
/**
* Structure describing a hunk of a diff.
*/
typedef struct {
int old_start; /** Starting line number in old_file */
int old_lines; /** Number of lines in old_file */
int new_start; /** Starting line number in new_file */
int new_lines; /** Number of lines in new_file */
} git_diff_range;
/**
* When iterating over a diff, callback that will be made per hunk.
*/
typedef int (*git_diff_hunk_cb)(
const git_diff_delta *delta,
const git_diff_range *range,
const char *header,
size_t header_len,
void *payload);
/**
* Line origin constants.
*
* These values describe where a line came from and will be passed to
* the git_diff_data_cb when iterating over a diff. There are some
* special origin constants at the end that are used for the text
* output callbacks to demarcate lines that are actually part of
* the file or hunk headers.
*/
typedef enum {
/* These values will be sent to `git_diff_data_cb` along with the line */
GIT_DIFF_LINE_CONTEXT = ' ',
GIT_DIFF_LINE_ADDITION = '+',
GIT_DIFF_LINE_DELETION = '-',
GIT_DIFF_LINE_CONTEXT_EOFNL = '=', /**< Both files have no LF at end */
GIT_DIFF_LINE_ADD_EOFNL = '>', /**< Old has no LF at end, new does */
GIT_DIFF_LINE_DEL_EOFNL = '<', /**< Old has LF at end, new does not */
/* The following values will only be sent to a `git_diff_data_cb` when
* the content of a diff is being formatted (eg. through
* git_diff_print_patch() or git_diff_print_compact(), for instance).
*/
GIT_DIFF_LINE_FILE_HDR = 'F',
GIT_DIFF_LINE_HUNK_HDR = 'H',
GIT_DIFF_LINE_BINARY = 'B'
} git_diff_line_t;
/**
* When iterating over a diff, callback that will be made per text diff
* line. In this context, the provided range will be NULL.
*
* When printing a diff, callback that will be made to output each line
* of text. This uses some extra GIT_DIFF_LINE_... constants for output
* of lines of file and hunk headers.
*/
typedef int (*git_diff_data_cb)(
const git_diff_delta *delta, /** delta that contains this data */
const git_diff_range *range, /** range of lines containing this data */
char line_origin, /** git_diff_list_t value from above */
const char *content, /** diff data - not NUL terminated */
size_t content_len, /** number of bytes of diff data */
void *payload); /** user reference data */
/**
* The diff patch is used to store all the text diffs for a delta.
*
* You can easily loop over the content of patches and get information about
* them.
*/
typedef struct git_diff_patch git_diff_patch;
/**
* Flags to control the behavior of diff rename/copy detection.
*/
typedef enum {
/** look for renames? (`--find-renames`) */
GIT_DIFF_FIND_RENAMES = (1 << 0),
/** consider old side of modified for renames? (`--break-rewrites=N`) */
GIT_DIFF_FIND_RENAMES_FROM_REWRITES = (1 << 1),
/** look for copies? (a la `--find-copies`) */
GIT_DIFF_FIND_COPIES = (1 << 2),
/** consider unmodified as copy sources? (`--find-copies-harder`) */
GIT_DIFF_FIND_COPIES_FROM_UNMODIFIED = (1 << 3),
/** split large rewrites into delete/add pairs (`--break-rewrites=/M`) */
GIT_DIFF_FIND_AND_BREAK_REWRITES = (1 << 4),
/** turn on all finding features */
GIT_DIFF_FIND_ALL = (0x1f),
/** measure similarity ignoring leading whitespace (default) */
GIT_DIFF_FIND_IGNORE_LEADING_WHITESPACE = 0,
/** measure similarity ignoring all whitespace */
GIT_DIFF_FIND_IGNORE_WHITESPACE = (1 << 6),
/** measure similarity including all data */
GIT_DIFF_FIND_DONT_IGNORE_WHITESPACE = (1 << 7),
} git_diff_find_t;
/**
* Pluggable similarity metric
*/
typedef struct {
int (*file_signature)(
void **out, const git_diff_file *file,
const char *fullpath, void *payload);
int (*buffer_signature)(
void **out, const git_diff_file *file,
const char *buf, size_t buflen, void *payload);
void (*free_signature)(void *sig, void *payload);
int (*similarity)(int *score, void *siga, void *sigb, void *payload);
void *payload;
} git_diff_similarity_metric;
/**
* Control behavior of rename and copy detection
*
* These options mostly mimic parameters that can be passed to git-diff.
*
* - `rename_threshold` is the same as the -M option with a value
* - `copy_threshold` is the same as the -C option with a value
* - `rename_from_rewrite_threshold` matches the top of the -B option
* - `break_rewrite_threshold` matches the bottom of the -B option
* - `target_limit` matches the -l option
*
* The `metric` option allows you to plug in a custom similarity metric.
* Set it to NULL for the default internal metric which is based on sampling
* hashes of ranges of data in the file. The default metric is a pretty
* good similarity approximation that should work fairly well for both text
* and binary data, and is pretty fast with fixed memory overhead.
*/
typedef struct {
unsigned int version;
/** Combination of git_diff_find_t values (default FIND_RENAMES) */
unsigned int flags;
/** Similarity to consider a file renamed (default 50) */
unsigned int rename_threshold;
/** Similarity of modified to be eligible rename source (default 50) */
unsigned int rename_from_rewrite_threshold;
/** Similarity to consider a file a copy (default 50) */
unsigned int copy_threshold;
/** Similarity to split modify into delete/add pair (default 60) */
unsigned int break_rewrite_threshold;
/** Maximum similarity sources to examine (a la diff's `-l` option or
* the `diff.renameLimit` config) (default 200)
*/
unsigned int target_limit;
/** Pluggable similarity metric; pass NULL to use internal metric */
git_diff_similarity_metric *metric;
} git_diff_find_options;
#define GIT_DIFF_FIND_OPTIONS_VERSION 1
#define GIT_DIFF_FIND_OPTIONS_INIT {GIT_DIFF_FIND_OPTIONS_VERSION}
/** @name Diff List Generator Functions
*
* These are the functions you would use to create (or destroy) a
* git_diff_list from various objects in a repository.
*/
/**@{*/
/**
* Deallocate a diff list.
*
* @param diff The previously created diff list; cannot be used after free.
*/
GIT_EXTERN(void) git_diff_list_free(git_diff_list *diff);
/**
* Create a diff list with the difference between two tree objects.
*
* This is equivalent to `git diff <old-tree> <new-tree>`
*
* The first tree will be used for the "old_file" side of the delta and the
* second tree will be used for the "new_file" side of the delta. You can
* pass NULL to indicate an empty tree, although it is an error to pass
* NULL for both the `old_tree` and `new_tree`.
*
* @param diff Output pointer to a git_diff_list pointer to be allocated.
* @param repo The repository containing the trees.
* @param old_tree A git_tree object to diff from, or NULL for empty tree.
* @param new_tree A git_tree object to diff to, or NULL for empty tree.
* @param opts Structure with options to influence diff or NULL for defaults.
*/
GIT_EXTERN(int) git_diff_tree_to_tree(
git_diff_list **diff,
git_repository *repo,
git_tree *old_tree,
git_tree *new_tree,
const git_diff_options *opts); /**< can be NULL for defaults */
/**
* Create a diff list between a tree and repository index.
*
* This is equivalent to `git diff --cached <treeish>` or if you pass
* the HEAD tree, then like `git diff --cached`.
*
* The tree you pass will be used for the "old_file" side of the delta, and
* the index will be used for the "new_file" side of the delta.
*
* @param diff Output pointer to a git_diff_list pointer to be allocated.
* @param repo The repository containing the tree and index.
* @param old_tree A git_tree object to diff from, or NULL for empty tree.
* @param index The index to diff with; repo index used if NULL.
* @param opts Structure with options to influence diff or NULL for defaults.
*/
GIT_EXTERN(int) git_diff_tree_to_index(
git_diff_list **diff,
git_repository *repo,
git_tree *old_tree,
git_index *index,
const git_diff_options *opts); /**< can be NULL for defaults */
/**
* Create a diff list between the repository index and the workdir directory.
*
* This matches the `git diff` command. See the note below on
* `git_diff_tree_to_workdir` for a discussion of the difference between
* `git diff` and `git diff HEAD` and how to emulate a `git diff <treeish>`
* using libgit2.
*
* The index will be used for the "old_file" side of the delta, and the
* working directory will be used for the "new_file" side of the delta.
*
* @param diff Output pointer to a git_diff_list pointer to be allocated.
* @param repo The repository.
* @param index The index to diff from; repo index used if NULL.
* @param opts Structure with options to influence diff or NULL for defaults.
*/
GIT_EXTERN(int) git_diff_index_to_workdir(
git_diff_list **diff,
git_repository *repo,
git_index *index,
const git_diff_options *opts); /**< can be NULL for defaults */
/**
* Create a diff list between a tree and the working directory.
*
* The tree you provide will be used for the "old_file" side of the delta,
* and the working directory will be used for the "new_file" side.
*
* Please note: this is *NOT* the same as `git diff <treeish>`. Running
* `git diff HEAD` or the like actually uses information from the index,
* along with the tree and working directory info.
*
* This function returns strictly the differences between the tree and the
* files contained in the working directory, regardless of the state of
* files in the index. It may come as a surprise, but there is no direct
* equivalent in core git.
*
* To emulate `git diff <treeish>`, call both `git_diff_tree_to_index` and
* `git_diff_index_to_workdir`, then call `git_diff_merge` on the results.
* That will yield a `git_diff_list` that matches the git output.
*
* If this seems confusing, take the case of a file with a staged deletion
* where the file has then been put back into the working dir and modified.
* The tree-to-workdir diff for that file is 'modified', but core git would
* show status 'deleted' since there is a pending deletion in the index.
*
* @param diff A pointer to a git_diff_list pointer that will be allocated.
* @param repo The repository containing the tree.
* @param old_tree A git_tree object to diff from, or NULL for empty tree.
* @param opts Structure with options to influence diff or NULL for defaults.
*/
GIT_EXTERN(int) git_diff_tree_to_workdir(
git_diff_list **diff,
git_repository *repo,
git_tree *old_tree,
const git_diff_options *opts); /**< can be NULL for defaults */
/**
* Merge one diff list into another.
*
* This merges items from the "from" list into the "onto" list. The
* resulting diff list will have all items that appear in either list.
* If an item appears in both lists, then it will be "merged" to appear
* as if the old version was from the "onto" list and the new version
* is from the "from" list (with the exception that if the item has a
* pending DELETE in the middle, then it will show as deleted).
*
* @param onto Diff to merge into.
* @param from Diff to merge.
*/
GIT_EXTERN(int) git_diff_merge(
git_diff_list *onto,
const git_diff_list *from);
/**
* Transform a diff list marking file renames, copies, etc.
*
* This modifies a diff list in place, replacing old entries that look
* like renames or copies with new entries reflecting those changes.
* This also will, if requested, break modified files into add/remove
* pairs if the amount of change is above a threshold.
*
* @param diff Diff list to run detection algorithms on
* @param options Control how detection should be run, NULL for defaults
* @return 0 on success, -1 on failure
*/
GIT_EXTERN(int) git_diff_find_similar(
git_diff_list *diff,
git_diff_find_options *options);
/**@}*/
/** @name Diff List Processor Functions
*
* These are the functions you apply to a diff list to process it
* or read it in some way.
*/
/**@{*/
/**
* Loop over all deltas in a diff list issuing callbacks.
*
* This will iterate through all of the files described in a diff. You
* should provide a file callback to learn about each file.
*
* The "hunk" and "line" callbacks are optional, and the text diff of the
* files will only be calculated if they are not NULL. Of course, these
* callbacks will not be invoked for binary files on the diff list or for
* files whose only changed is a file mode change.
*
* Returning a non-zero value from any of the callbacks will terminate
* the iteration and cause this return `GIT_EUSER`.
*
* @param diff A git_diff_list generated by one of the above functions.
* @param file_cb Callback function to make per file in the diff.
* @param hunk_cb Optional callback to make per hunk of text diff. This
* callback is called to describe a range of lines in the
* diff. It will not be issued for binary files.
* @param line_cb Optional callback to make per line of diff text. This
* same callback will be made for context lines, added, and
* removed lines, and even for a deleted trailing newline.
* @param payload Reference pointer that will be passed to your callbacks.
* @return 0 on success, GIT_EUSER on non-zero callback, or error code
*/
GIT_EXTERN(int) git_diff_foreach(
git_diff_list *diff,
git_diff_file_cb file_cb,
git_diff_hunk_cb hunk_cb,
git_diff_data_cb line_cb,
void *payload);
/**
* Iterate over a diff generating text output like "git diff --name-status".
*
* Returning a non-zero value from the callbacks will terminate the
* iteration and cause this return `GIT_EUSER`.
*
* @param diff A git_diff_list generated by one of the above functions.
* @param print_cb Callback to make per line of diff text.
* @param payload Reference pointer that will be passed to your callback.
* @return 0 on success, GIT_EUSER on non-zero callback, or error code
*/
GIT_EXTERN(int) git_diff_print_compact(
git_diff_list *diff,
git_diff_data_cb print_cb,
void *payload);
/**
* Iterate over a diff generating text output like "git diff --raw".
*
* Returning a non-zero value from the callbacks will terminate the
* iteration and cause this return `GIT_EUSER`.
*
* @param diff A git_diff_list generated by one of the above functions.
* @param print_cb Callback to make per line of diff text.
* @param payload Reference pointer that will be passed to your callback.
* @return 0 on success, GIT_EUSER on non-zero callback, or error code
*/
GIT_EXTERN(int) git_diff_print_raw(
git_diff_list *diff,
git_diff_data_cb print_cb,
void *payload);
/**
* Look up the single character abbreviation for a delta status code.
*
* When you call `git_diff_print_compact` it prints single letter codes into
* the output such as 'A' for added, 'D' for deleted, 'M' for modified, etc.
* It is sometimes convenient to convert a git_delta_t value into these
* letters for your own purposes. This function does just that. By the
* way, unmodified will return a space (i.e. ' ').
*
* @param delta_t The git_delta_t value to look up
* @return The single character label for that code
*/
GIT_EXTERN(char) git_diff_status_char(git_delta_t status);
/**
* Iterate over a diff generating text output like "git diff".
*
* This is a super easy way to generate a patch from a diff.
*
* Returning a non-zero value from the callbacks will terminate the
* iteration and cause this return `GIT_EUSER`.
*
* @param diff A git_diff_list generated by one of the above functions.
* @param payload Reference pointer that will be passed to your callbacks.
* @param print_cb Callback function to output lines of the diff. This
* same function will be called for file headers, hunk
* headers, and diff lines. Fortunately, you can probably
* use various GIT_DIFF_LINE constants to determine what
* text you are given.
* @return 0 on success, GIT_EUSER on non-zero callback, or error code
*/
GIT_EXTERN(int) git_diff_print_patch(
git_diff_list *diff,
git_diff_data_cb print_cb,
void *payload);
/**
* Query how many diff records are there in a diff list.
*
* @param diff A git_diff_list generated by one of the above functions
* @return Count of number of deltas in the list
*/
GIT_EXTERN(size_t) git_diff_num_deltas(git_diff_list *diff);
/**
* Query how many diff deltas are there in a diff list filtered by type.
*
* This works just like `git_diff_entrycount()` with an extra parameter
* that is a `git_delta_t` and returns just the count of how many deltas
* match that particular type.
*
* @param diff A git_diff_list generated by one of the above functions
* @param type A git_delta_t value to filter the count
* @return Count of number of deltas matching delta_t type
*/
GIT_EXTERN(size_t) git_diff_num_deltas_of_type(
git_diff_list *diff,
git_delta_t type);
/**
* Return the diff delta and patch for an entry in the diff list.
*
* The `git_diff_patch` is a newly created object contains the text diffs
* for the delta. You have to call `git_diff_patch_free()` when you are
* done with it. You can use the patch object to loop over all the hunks
* and lines in the diff of the one delta.
*
* For an unchanged file or a binary file, no `git_diff_patch` will be
* created, the output will be set to NULL, and the `binary` flag will be
* set true in the `git_diff_delta` structure.
*
* The `git_diff_delta` pointer points to internal data and you do not have
* to release it when you are done with it. It will go away when the
* `git_diff_list` and `git_diff_patch` go away.
*
* It is okay to pass NULL for either of the output parameters; if you pass
* NULL for the `git_diff_patch`, then the text diff will not be calculated.
*
* @param patch_out Output parameter for the delta patch object
* @param delta_out Output parameter for the delta object
* @param diff Diff list object
* @param idx Index into diff list
* @return 0 on success, other value < 0 on error
*/
GIT_EXTERN(int) git_diff_get_patch(
git_diff_patch **patch_out,
const git_diff_delta **delta_out,
git_diff_list *diff,
size_t idx);
/**
* Free a git_diff_patch object.
*/
GIT_EXTERN(void) git_diff_patch_free(
git_diff_patch *patch);
/**
* Get the delta associated with a patch
*/
GIT_EXTERN(const git_diff_delta *) git_diff_patch_delta(
git_diff_patch *patch);
/**
* Get the number of hunks in a patch
*/
GIT_EXTERN(size_t) git_diff_patch_num_hunks(
git_diff_patch *patch);
/**
* Get line counts of each type in a patch.
*
* This helps imitate a diff --numstat type of output. For that purpose,
* you only need the `total_additions` and `total_deletions` values, but we
* include the `total_context` line count in case you want the total number
* of lines of diff output that will be generated.
*
* All outputs are optional. Pass NULL if you don't need a particular count.
*
* @param total_context Count of context lines in output, can be NULL.
* @param total_additions Count of addition lines in output, can be NULL.
* @param total_deletions Count of deletion lines in output, can be NULL.
* @param patch The git_diff_patch object
* @return Number of lines in hunk or -1 if invalid hunk index
*/
GIT_EXTERN(int) git_diff_patch_line_stats(
size_t *total_context,
size_t *total_additions,
size_t *total_deletions,
const git_diff_patch *patch);
/**
* Get the information about a hunk in a patch
*
* Given a patch and a hunk index into the patch, this returns detailed
* information about that hunk. Any of the output pointers can be passed
* as NULL if you don't care about that particular piece of information.
*
* @param range Output pointer to git_diff_range of hunk
* @param header Output pointer to header string for hunk. Unlike the
* content pointer for each line, this will be NUL-terminated
* @param header_len Output value of characters in header string
* @param lines_in_hunk Output count of total lines in this hunk
* @param patch Input pointer to patch object
* @param hunk_idx Input index of hunk to get information about
* @return 0 on success, GIT_ENOTFOUND if hunk_idx out of range, <0 on error
*/
GIT_EXTERN(int) git_diff_patch_get_hunk(
const git_diff_range **range,
const char **header,
size_t *header_len,
size_t *lines_in_hunk,
git_diff_patch *patch,
size_t hunk_idx);
/**
* Get the number of lines in a hunk.
*
* @param patch The git_diff_patch object
* @param hunk_idx Index of the hunk
* @return Number of lines in hunk or -1 if invalid hunk index
*/
GIT_EXTERN(int) git_diff_patch_num_lines_in_hunk(
git_diff_patch *patch,
size_t hunk_idx);
/**
* Get data about a line in a hunk of a patch.
*
* Given a patch, a hunk index, and a line index in the hunk, this
* will return a lot of details about that line. If you pass a hunk
* index larger than the number of hunks or a line index larger than
* the number of lines in the hunk, this will return -1.
*
* @param line_origin A GIT_DIFF_LINE constant from above
* @param content Pointer to content of diff line, not NUL-terminated
* @param content_len Number of characters in content
* @param old_lineno Line number in old file or -1 if line is added
* @param new_lineno Line number in new file or -1 if line is deleted
* @param patch The patch to look in
* @param hunk_idx The index of the hunk
* @param line_of_index The index of the line in the hunk
* @return 0 on success, <0 on failure
*/
GIT_EXTERN(int) git_diff_patch_get_line_in_hunk(
char *line_origin,
const char **content,
size_t *content_len,
int *old_lineno,
int *new_lineno,
git_diff_patch *patch,
size_t hunk_idx,
size_t line_of_hunk);
/**
* Serialize the patch to text via callback.
*
* Returning a non-zero value from the callback will terminate the iteration
* and cause this return `GIT_EUSER`.
*
* @param patch A git_diff_patch representing changes to one file
* @param print_cb Callback function to output lines of the patch. Will be
* called for file headers, hunk headers, and diff lines.
* @param payload Reference pointer that will be passed to your callbacks.
* @return 0 on success, GIT_EUSER on non-zero callback, or error code
*/
GIT_EXTERN(int) git_diff_patch_print(
git_diff_patch *patch,
git_diff_data_cb print_cb,
void *payload);
/**
* Get the content of a patch as a single diff text.
*
* @param string Allocated string; caller must free.
* @param patch A git_diff_patch representing changes to one file
* @return 0 on success, <0 on failure.
*/
GIT_EXTERN(int) git_diff_patch_to_str(
char **string,
git_diff_patch *patch);
/**@}*/
/*
* Misc
*/
/**
* Directly run a diff on two blobs.
*
* Compared to a file, a blob lacks some contextual information. As such,
* the `git_diff_file` given to the callback will have some fake data; i.e.
* `mode` will be 0 and `path` will be NULL.
*
* NULL is allowed for either `old_blob` or `new_blob` and will be treated
* as an empty blob, with the `oid` set to NULL in the `git_diff_file` data.
* Passing NULL for both blobs is a noop; no callbacks will be made at all.
*
* We do run a binary content check on the blob content and if either blob
* looks like binary data, the `git_diff_delta` binary attribute will be set
* to 1 and no call to the hunk_cb nor line_cb will be made (unless you pass
* `GIT_DIFF_FORCE_TEXT` of course).
*
* @param old_blob Blob for old side of diff, or NULL for empty blob
* @param new_blob Blob for new side of diff, or NULL for empty blob
* @param options Options for diff, or NULL for default options
* @param file_cb Callback for "file"; made once if there is a diff; can be NULL
* @param hunk_cb Callback for each hunk in diff; can be NULL
* @param line_cb Callback for each line in diff; can be NULL
* @param payload Payload passed to each callback function
* @return 0 on success, GIT_EUSER on non-zero callback return, or error code
*/
GIT_EXTERN(int) git_diff_blobs(
const git_blob *old_blob,
const git_blob *new_blob,
const git_diff_options *options,
git_diff_file_cb file_cb,
git_diff_hunk_cb hunk_cb,
git_diff_data_cb line_cb,
void *payload);
/**
* Directly run a diff between a blob and a buffer.
*
* As with `git_diff_blobs`, comparing a blob and buffer lacks some context,
* so the `git_diff_file` parameters to the callbacks will be faked a la the
* rules for `git_diff_blobs()`.
*
* Passing NULL for `old_blob` will be treated as an empty blob (i.e. the
* `file_cb` will be invoked with GIT_DELTA_ADDED and the diff will be the
* entire content of the buffer added). Passing NULL to the buffer will do
* the reverse, with GIT_DELTA_REMOVED and blob content removed.
*
* @param old_blob Blob for old side of diff, or NULL for empty blob
* @param buffer Raw data for new side of diff
* @param buffer_len Length of raw data for new side of diff
* @param options Options for diff, or NULL for default options
* @param file_cb Callback for "file"; made once if there is a diff; can be NULL
* @param hunk_cb Callback for each hunk in diff; can be NULL
* @param line_cb Callback for each line in diff; can be NULL
* @param payload Payload passed to each callback function
* @return 0 on success, GIT_EUSER on non-zero callback return, or error code
*/
GIT_EXTERN(int) git_diff_blob_to_buffer(
const git_blob *old_blob,
const char *buffer,
size_t buffer_len,
const git_diff_options *options,
git_diff_file_cb file_cb,
git_diff_hunk_cb hunk_cb,
git_diff_data_cb data_cb,
void *payload);
GIT_END_DECL
/** @} */
#endif
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