include/git2/checkout.h

   1 /*
   2  * Copyright (C) the libgit2 contributors. All rights reserved.
   3  *
   4  * This file is part of libgit2, distributed under the GNU GPL v2 with
   5  * a Linking Exception. For full terms see the included COPYING file.
   6  */
   7 #ifndef INCLUDE_git_checkout_h__
   8 #define INCLUDE_git_checkout_h__
   9
  10 #include "common.h"
  11 #include "types.h"
  12 #include "diff.h"
  13
  14 /**
  15  * @file git2/checkout.h
  16  * @brief Git checkout routines
  17  * @defgroup git_checkout Git checkout routines
  18  * @ingroup Git
  19  * @{
  20  */
  21 GIT_BEGIN_DECL
  22
  23 /**
  24  * Checkout behavior flags
  25  *
  26  * In libgit2, checkout is used to update the working directory and index
  27  * to match a target tree.  Unlike git checkout, it does not move the HEAD
  28  * commit for you - use `git_repository_set_head` or the like to do that.
  29  *
  30  * Checkout looks at (up to) four things: the "target" tree you want to
  31  * check out, the "baseline" tree of what was checked out previously, the
  32  * working directory for actual files, and the index for staged changes.
  33  *
  34  * You give checkout one of three strategies for update:
  35  *
  36  * - `GIT_CHECKOUT_NONE` is a dry-run strategy that checks for conflicts,
  37  *   etc., but doesn't make any actual changes.
  38  *
  39  * - `GIT_CHECKOUT_FORCE` is at the opposite extreme, taking any action to
  40  *   make the working directory match the target (including potentially
  41  *   discarding modified files).
  42  *
  43  * - `GIT_CHECKOUT_SAFE` is between these two options, it will only make
  44  *   modifications that will not lose changes.
  45  *
  46  *                         |  target == baseline   |  target != baseline  |
  47  *    ---------------------|-----------------------|----------------------|
  48  *     workdir == baseline |       no action       |  create, update, or  |
  49  *                         |                       |     delete file      |
  50  *    ---------------------|-----------------------|----------------------|
  51  *     workdir exists and  |       no action       |   conflict (notify   |
  52  *       is != baseline    | notify dirty MODIFIED | and cancel checkout) |
  53  *    ---------------------|-----------------------|----------------------|
  54  *      workdir missing,   | notify dirty DELETED  |     create file      |
  55  *      baseline present   |                       |                      |
  56  *    ---------------------|-----------------------|----------------------|
  57  *
  58  * To emulate `git checkout`, use `GIT_CHECKOUT_SAFE` with a checkout
  59  * notification callback (see below) that displays information about dirty
  60  * files.  The default behavior will cancel checkout on conflicts.
  61  *
  62  * To emulate `git checkout-index`, use `GIT_CHECKOUT_SAFE` with a
  63  * notification callback that cancels the operation if a dirty-but-existing
  64  * file is found in the working directory.  This core git command isn't
  65  * quite "force" but is sensitive about some types of changes.
  66  *
  67  * To emulate `git checkout -f`, use `GIT_CHECKOUT_FORCE`.
  68  *
  69  *
  70  * There are some additional flags to modify the behavior of checkout:
  71  *
  72  * - GIT_CHECKOUT_ALLOW_CONFLICTS makes SAFE mode apply safe file updates
  73  *   even if there are conflicts (instead of cancelling the checkout).
  74  *
  75  * - GIT_CHECKOUT_REMOVE_UNTRACKED means remove untracked files (i.e. not
  76  *   in target, baseline, or index, and not ignored) from the working dir.
  77  *
  78  * - GIT_CHECKOUT_REMOVE_IGNORED means remove ignored files (that are also
  79  *   untracked) from the working directory as well.
  80  *
  81  * - GIT_CHECKOUT_UPDATE_ONLY means to only update the content of files that
  82  *   already exist.  Files will not be created nor deleted.  This just skips
  83  *   applying adds, deletes, and typechanges.
  84  *
  85  * - GIT_CHECKOUT_DONT_UPDATE_INDEX prevents checkout from writing the
  86  *   updated files' information to the index.
  87  *
  88  * - Normally, checkout will reload the index and git attributes from disk
  89  *   before any operations.  GIT_CHECKOUT_NO_REFRESH prevents this reload.
  90  *
  91  * - Unmerged index entries are conflicts.  GIT_CHECKOUT_SKIP_UNMERGED skips
  92  *   files with unmerged index entries instead.  GIT_CHECKOUT_USE_OURS and
  93  *   GIT_CHECKOUT_USE_THEIRS to proceed with the checkout using either the
  94  *   stage 2 ("ours") or stage 3 ("theirs") version of files in the index.
  95  *
  96  * - GIT_CHECKOUT_DONT_OVERWRITE_IGNORED prevents ignored files from being
  97  *   overwritten.  Normally, files that are ignored in the working directory
  98  *   are not considered "precious" and may be overwritten if the checkout
  99  *   target contains that file.
 100  *
 101  * - GIT_CHECKOUT_DONT_REMOVE_EXISTING prevents checkout from removing
 102  *   files or folders that fold to the same name on case insensitive
 103  *   filesystems.  This can cause files to retain their existing names
 104  *   and write through existing symbolic links.
 105  */
 106 typedef enum {
 107         GIT_CHECKOUT_NONE = 0, /**< default is a dry run, no actual updates */
 108
 109         /**
 110          * Allow safe updates that cannot overwrite uncommitted data.
 111          * If the uncommitted changes don't conflict with the checked out files,
 112          * the checkout will still proceed, leaving the changes intact.
 113          *
 114          * Mutually exclusive with GIT_CHECKOUT_FORCE.
 115          * GIT_CHECKOUT_FORCE takes precedence over GIT_CHECKOUT_SAFE.
 116          */
 117         GIT_CHECKOUT_SAFE = (1u << 0),
 118
 119         /**
 120          * Allow all updates to force working directory to look like index.
 121          *
 122          * Mutually exclusive with GIT_CHECKOUT_SAFE.
 123          * GIT_CHECKOUT_FORCE takes precedence over GIT_CHECKOUT_SAFE.
 124          */
 125         GIT_CHECKOUT_FORCE = (1u << 1),
 126
 127
 128         /** Allow checkout to recreate missing files */
 129         GIT_CHECKOUT_RECREATE_MISSING = (1u << 2),
 130
 131         /** Allow checkout to make safe updates even if conflicts are found */
 132         GIT_CHECKOUT_ALLOW_CONFLICTS = (1u << 4),
 133
 134         /** Remove untracked files not in index (that are not ignored) */
 135         GIT_CHECKOUT_REMOVE_UNTRACKED = (1u << 5),
 136
 137         /** Remove ignored files not in index */
 138         GIT_CHECKOUT_REMOVE_IGNORED = (1u << 6),
 139
 140         /** Only update existing files, don't create new ones */
 141         GIT_CHECKOUT_UPDATE_ONLY = (1u << 7),
 142
 143         /**
 144          * Normally checkout updates index entries as it goes; this stops that.
 145          * Implies `GIT_CHECKOUT_DONT_WRITE_INDEX`.
 146          */
 147         GIT_CHECKOUT_DONT_UPDATE_INDEX = (1u << 8),
 148
 149         /** Don't refresh index/config/etc before doing checkout */
 150         GIT_CHECKOUT_NO_REFRESH = (1u << 9),
 151
 152         /** Allow checkout to skip unmerged files */
 153         GIT_CHECKOUT_SKIP_UNMERGED = (1u << 10),
 154         /** For unmerged files, checkout stage 2 from index */
 155         GIT_CHECKOUT_USE_OURS = (1u << 11),
 156         /** For unmerged files, checkout stage 3 from index */
 157         GIT_CHECKOUT_USE_THEIRS = (1u << 12),
 158
 159         /** Treat pathspec as simple list of exact match file paths */
 160         GIT_CHECKOUT_DISABLE_PATHSPEC_MATCH = (1u << 13),
 161
 162         /** Ignore directories in use, they will be left empty */
 163         GIT_CHECKOUT_SKIP_LOCKED_DIRECTORIES = (1u << 18),
 164
 165         /** Don't overwrite ignored files that exist in the checkout target */
 166         GIT_CHECKOUT_DONT_OVERWRITE_IGNORED = (1u << 19),
 167
 168         /** Write normal merge files for conflicts */
 169         GIT_CHECKOUT_CONFLICT_STYLE_MERGE = (1u << 20),
 170
 171         /** Include common ancestor data in diff3 format files for conflicts */
 172         GIT_CHECKOUT_CONFLICT_STYLE_DIFF3 = (1u << 21),
 173
 174         /** Don't overwrite existing files or folders */
 175         GIT_CHECKOUT_DONT_REMOVE_EXISTING = (1u << 22),
 176
 177         /** Normally checkout writes the index upon completion; this prevents that. */
 178         GIT_CHECKOUT_DONT_WRITE_INDEX = (1u << 23),
 179
 180         /**
 181          * THE FOLLOWING OPTIONS ARE NOT YET IMPLEMENTED
 182          */
 183
 184         /** Recursively checkout submodules with same options (NOT IMPLEMENTED) */
 185         GIT_CHECKOUT_UPDATE_SUBMODULES = (1u << 16),
 186         /** Recursively checkout submodules if HEAD moved in super repo (NOT IMPLEMENTED) */
 187         GIT_CHECKOUT_UPDATE_SUBMODULES_IF_CHANGED = (1u << 17),
 188
 189 } git_checkout_strategy_t;
 190
 191 /**
 192  * Checkout notification flags
 193  *
 194  * Checkout will invoke an options notification callback (`notify_cb`) for
 195  * certain cases - you pick which ones via `notify_flags`:
 196  *
 197  * - GIT_CHECKOUT_NOTIFY_CONFLICT invokes checkout on conflicting paths.
 198  *
 199  * - GIT_CHECKOUT_NOTIFY_DIRTY notifies about "dirty" files, i.e. those that
 200  *   do not need an update but no longer match the baseline.  Core git
 201  *   displays these files when checkout runs, but won't stop the checkout.
 202  *
 203  * - GIT_CHECKOUT_NOTIFY_UPDATED sends notification for any file changed.
 204  *
 205  * - GIT_CHECKOUT_NOTIFY_UNTRACKED notifies about untracked files.
 206  *
 207  * - GIT_CHECKOUT_NOTIFY_IGNORED notifies about ignored files.
 208  *
 209  * Returning a non-zero value from this callback will cancel the checkout.
 210  * The non-zero return value will be propagated back and returned by the
 211  * git_checkout_... call.
 212  *
 213  * Notification callbacks are made prior to modifying any files on disk,
 214  * so canceling on any notification will still happen prior to any files
 215  * being modified.
 216  */
 217 typedef enum {
 218         GIT_CHECKOUT_NOTIFY_NONE      = 0,
 219         GIT_CHECKOUT_NOTIFY_CONFLICT  = (1u << 0),
 220         GIT_CHECKOUT_NOTIFY_DIRTY     = (1u << 1),
 221         GIT_CHECKOUT_NOTIFY_UPDATED   = (1u << 2),
 222         GIT_CHECKOUT_NOTIFY_UNTRACKED = (1u << 3),
 223         GIT_CHECKOUT_NOTIFY_IGNORED   = (1u << 4),
 224
 225         GIT_CHECKOUT_NOTIFY_ALL       = 0x0FFFFu
 226 } git_checkout_notify_t;
 227
 228 /** Checkout performance-reporting structure */
 229 typedef struct {
 230         size_t mkdir_calls;
 231         size_t stat_calls;
 232         size_t chmod_calls;
 233 } git_checkout_perfdata;
 234
 235 /** Checkout notification callback function */
 236 typedef int GIT_CALLBACK(git_checkout_notify_cb)(
 237         git_checkout_notify_t why,
 238         const char *path,
 239         const git_diff_file *baseline,
 240         const git_diff_file *target,
 241         const git_diff_file *workdir,
 242         void *payload);
 243
 244 /** Checkout progress notification function */
 245 typedef void GIT_CALLBACK(git_checkout_progress_cb)(
 246         const char *path,
 247         size_t completed_steps,
 248         size_t total_steps,
 249         void *payload);
 250
 251 /** Checkout perfdata notification function */
 252 typedef void GIT_CALLBACK(git_checkout_perfdata_cb)(
 253         const git_checkout_perfdata *perfdata,
 254         void *payload);
 255
 256 /**
 257  * Checkout options structure
 258  *
 259  * Initialize with `GIT_CHECKOUT_OPTIONS_INIT`. Alternatively, you can
 260  * use `git_checkout_options_init`.
 261  *
 262  */
 263 typedef struct git_checkout_options {
 264         unsigned int version; /**< The version */
 265
 266         unsigned int checkout_strategy; /**< default will be a safe checkout */
 267
 268         int disable_filters;    /**< don't apply filters like CRLF conversion */
 269         unsigned int dir_mode;  /**< default is 0755 */
 270         unsigned int file_mode; /**< default is 0644 or 0755 as dictated by blob */
 271         int file_open_flags;    /**< default is O_CREAT | O_TRUNC | O_WRONLY */
 272
 273         unsigned int notify_flags; /**< see `git_checkout_notify_t` above */
 274
 275         /**
 276          * Optional callback to get notifications on specific file states.
 277          * @see git_checkout_notify_t
 278          */
 279         git_checkout_notify_cb notify_cb;
 280
 281         /** Payload passed to notify_cb */
 282         void *notify_payload;
 283
 284         /** Optional callback to notify the consumer of checkout progress. */
 285         git_checkout_progress_cb progress_cb;
 286
 287         /** Payload passed to progress_cb */
 288         void *progress_payload;
 289
 290         /**
 291          * A list of wildmatch patterns or paths.
 292          *
 293          * By default, all paths are processed. If you pass an array of wildmatch
 294          * patterns, those will be used to filter which paths should be taken into
 295          * account.
 296          *
 297          * Use GIT_CHECKOUT_DISABLE_PATHSPEC_MATCH to treat as a simple list.
 298          */
 299         git_strarray paths;
 300
 301         /**
 302          * The expected content of the working directory; defaults to HEAD.
 303          *
 304          * If the working directory does not match this baseline information,
 305          * that will produce a checkout conflict.
 306          */
 307         git_tree *baseline;
 308
 309         /**
 310          * Like `baseline` above, though expressed as an index.  This
 311          * option overrides `baseline`.
 312          */
 313         git_index *baseline_index;
 314
 315         const char *target_directory; /**< alternative checkout path to workdir */
 316
 317         const char *ancestor_label; /**< the name of the common ancestor side of conflicts */
 318         const char *our_label; /**< the name of the "our" side of conflicts */
 319         const char *their_label; /**< the name of the "their" side of conflicts */
 320
 321         /** Optional callback to notify the consumer of performance data. */
 322         git_checkout_perfdata_cb perfdata_cb;
 323
 324         /** Payload passed to perfdata_cb */
 325         void *perfdata_payload;
 326 } git_checkout_options;
 327
 328 #define GIT_CHECKOUT_OPTIONS_VERSION 1
 329 #define GIT_CHECKOUT_OPTIONS_INIT {GIT_CHECKOUT_OPTIONS_VERSION, GIT_CHECKOUT_SAFE}
 330
 331 /**
 332  * Initialize git_checkout_options structure
 333  *
 334  * Initializes a `git_checkout_options` with default values. Equivalent to creating
 335  * an instance with GIT_CHECKOUT_OPTIONS_INIT.
 336  *
 337  * @param opts The `git_checkout_options` struct to initialize.
 338  * @param version The struct version; pass `GIT_CHECKOUT_OPTIONS_VERSION`.
 339  * @return Zero on success; -1 on failure.
 340  */
 341 GIT_EXTERN(int) git_checkout_options_init(
 342         git_checkout_options *opts,
 343         unsigned int version);
 344
 345 /**
 346  * Updates files in the index and the working tree to match the content of
 347  * the commit pointed at by HEAD.
 348  *
 349  * Note that this is _not_ the correct mechanism used to switch branches;
 350  * do not change your `HEAD` and then call this method, that would leave
 351  * you with checkout conflicts since your working directory would then
 352  * appear to be dirty.  Instead, checkout the target of the branch and
 353  * then update `HEAD` using `git_repository_set_head` to point to the
 354  * branch you checked out.
 355  *
 356  * @param repo repository to check out (must be non-bare)
 357  * @param opts specifies checkout options (may be NULL)
 358  * @return 0 on success, GIT_EUNBORNBRANCH if HEAD points to a non
 359  *         existing branch, non-zero value returned by `notify_cb`, or
 360  *         other error code < 0 (use git_error_last for error details)
 361  */
 362 GIT_EXTERN(int) git_checkout_head(
 363         git_repository *repo,
 364         const git_checkout_options *opts);
 365
 366 /**
 367  * Updates files in the working tree to match the content of the index.
 368  *
 369  * @param repo repository into which to check out (must be non-bare)
 370  * @param index index to be checked out (or NULL to use repository index)
 371  * @param opts specifies checkout options (may be NULL)
 372  * @return 0 on success, non-zero return value from `notify_cb`, or error
 373  *         code < 0 (use git_error_last for error details)
 374  */
 375 GIT_EXTERN(int) git_checkout_index(
 376         git_repository *repo,
 377         git_index *index,
 378         const git_checkout_options *opts);
 379
 380 /**
 381  * Updates files in the index and working tree to match the content of the
 382  * tree pointed at by the treeish.
 383  *
 384  * @param repo repository to check out (must be non-bare)
 385  * @param treeish a commit, tag or tree which content will be used to update
 386  * the working directory (or NULL to use HEAD)
 387  * @param opts specifies checkout options (may be NULL)
 388  * @return 0 on success, non-zero return value from `notify_cb`, or error
 389  *         code < 0 (use git_error_last for error details)
 390  */
 391 GIT_EXTERN(int) git_checkout_tree(
 392         git_repository *repo,
 393         const git_object *treeish,
 394         const git_checkout_options *opts);
 395
 396 /** @} */
 397 GIT_END_DECL
 398 #endif