reset.c

   1 #define USE_THE_REPOSITORY_VARIABLE
   2
   3 #include "git-compat-util.h"
   4 #include "cache-tree.h"
   5 #include "gettext.h"
   6 #include "hex.h"
   7 #include "lockfile.h"
   8 #include "object-name.h"
   9 #include "refs.h"
  10 #include "reset.h"
  11 #include "tree-walk.h"
  12 #include "tree.h"
  13 #include "unpack-trees.h"
  14 #include "hook.h"
  15
  16 static int update_refs(const struct reset_head_opts *opts,
  17                        const struct object_id *oid,
  18                        const struct object_id *head)
  19 {
  20         unsigned detach_head = opts->flags & RESET_HEAD_DETACH;
  21         unsigned run_hook = opts->flags & RESET_HEAD_RUN_POST_CHECKOUT_HOOK;
  22         unsigned update_orig_head = opts->flags & RESET_ORIG_HEAD;
  23         const struct object_id *orig_head = opts->orig_head;
  24         const char *switch_to_branch = opts->branch;
  25         const char *reflog_branch = opts->branch_msg;
  26         const char *reflog_head = opts->head_msg;
  27         const char *reflog_orig_head = opts->orig_head_msg;
  28         const char *default_reflog_action = opts->default_reflog_action;
  29         struct object_id *old_orig = NULL, oid_old_orig;
  30         struct strbuf msg = STRBUF_INIT;
  31         const char *reflog_action;
  32         size_t prefix_len;
  33         int ret;
  34
  35         if ((update_orig_head && !reflog_orig_head) || !reflog_head) {
  36                 if (!default_reflog_action)
  37                         BUG("default_reflog_action must be given when reflog messages are omitted");
  38                 reflog_action = getenv(GIT_REFLOG_ACTION_ENVIRONMENT);
  39                 strbuf_addf(&msg, "%s: ", reflog_action ? reflog_action :
  40                                                           default_reflog_action);
  41         }
  42         prefix_len = msg.len;
  43
  44         if (update_orig_head) {
  45                 if (!repo_get_oid(the_repository, "ORIG_HEAD", &oid_old_orig))
  46                         old_orig = &oid_old_orig;
  47                 if (head) {
  48                         if (!reflog_orig_head) {
  49                                 strbuf_addstr(&msg, "updating ORIG_HEAD");
  50                                 reflog_orig_head = msg.buf;
  51                         }
  52                         refs_update_ref(get_main_ref_store(the_repository),
  53                                         reflog_orig_head, "ORIG_HEAD",
  54                                         orig_head ? orig_head : head,
  55                                         old_orig, 0, UPDATE_REFS_MSG_ON_ERR);
  56                 } else if (old_orig)
  57                         refs_delete_ref(get_main_ref_store(the_repository),
  58                                         NULL, "ORIG_HEAD", old_orig, 0);
  59         }
  60
  61         if (!reflog_head) {
  62                 strbuf_setlen(&msg, prefix_len);
  63                 strbuf_addstr(&msg, "updating HEAD");
  64                 reflog_head = msg.buf;
  65         }
  66         if (!switch_to_branch)
  67                 ret = refs_update_ref(get_main_ref_store(the_repository),
  68                                       reflog_head, "HEAD", oid, head,
  69                                       detach_head ? REF_NO_DEREF : 0,
  70                                       UPDATE_REFS_MSG_ON_ERR);
  71         else {
  72                 ret = refs_update_ref(get_main_ref_store(the_repository),
  73                                       reflog_branch ? reflog_branch : reflog_head,
  74                                       switch_to_branch, oid, NULL, 0,
  75                                       UPDATE_REFS_MSG_ON_ERR);
  76                 if (!ret)
  77                         ret = refs_update_symref(get_main_ref_store(the_repository),
  78                                                  "HEAD", switch_to_branch,
  79                                                  reflog_head);
  80         }
  81         if (!ret && run_hook)
  82                 run_hooks_l(the_repository, "post-checkout",
  83                             oid_to_hex(head ? head : null_oid()),
  84                             oid_to_hex(oid), "1", NULL);
  85         strbuf_release(&msg);
  86         return ret;
  87 }
  88
  89 int reset_head(struct repository *r, const struct reset_head_opts *opts)
  90 {
  91         const struct object_id *oid = opts->oid;
  92         const char *switch_to_branch = opts->branch;
  93         unsigned reset_hard = opts->flags & RESET_HEAD_HARD;
  94         unsigned refs_only = opts->flags & RESET_HEAD_REFS_ONLY;
  95         unsigned update_orig_head = opts->flags & RESET_ORIG_HEAD;
  96         struct object_id *head = NULL, head_oid;
  97         struct tree_desc desc[2] = { { NULL }, { NULL } };
  98         struct lock_file lock = LOCK_INIT;
  99         struct unpack_trees_options unpack_tree_opts = { 0 };
 100         struct tree *tree;
 101         const char *action;
 102         int ret = 0, nr = 0;
 103
 104         if (switch_to_branch && !starts_with(switch_to_branch, "refs/"))
 105                 BUG("Not a fully qualified branch: '%s'", switch_to_branch);
 106
 107         if (opts->orig_head_msg && !update_orig_head)
 108                 BUG("ORIG_HEAD reflog message given without updating ORIG_HEAD");
 109
 110         if (opts->branch_msg && !opts->branch)
 111                 BUG("branch reflog message given without a branch");
 112
 113         if (!refs_only && repo_hold_locked_index(r, &lock, LOCK_REPORT_ON_ERROR) < 0) {
 114                 ret = -1;
 115                 goto leave_reset_head;
 116         }
 117
 118         if (!repo_get_oid(r, "HEAD", &head_oid)) {
 119                 head = &head_oid;
 120         } else if (!oid || !reset_hard) {
 121                 ret = error(_("could not determine HEAD revision"));
 122                 goto leave_reset_head;
 123         }
 124
 125         if (!oid)
 126                 oid = &head_oid;
 127
 128         if (refs_only)
 129                 return update_refs(opts, oid, head);
 130
 131         action = reset_hard ? "reset" : "checkout";
 132         setup_unpack_trees_porcelain(&unpack_tree_opts, action);
 133         unpack_tree_opts.head_idx = 1;
 134         unpack_tree_opts.src_index = r->index;
 135         unpack_tree_opts.dst_index = r->index;
 136         unpack_tree_opts.fn = reset_hard ? oneway_merge : twoway_merge;
 137         unpack_tree_opts.update = 1;
 138         unpack_tree_opts.merge = 1;
 139         unpack_tree_opts.preserve_ignored = 0; /* FIXME: !overwrite_ignore */
 140         unpack_tree_opts.skip_cache_tree_update = 1;
 141         init_checkout_metadata(&unpack_tree_opts.meta, switch_to_branch, oid, NULL);
 142         if (reset_hard)
 143                 unpack_tree_opts.reset = UNPACK_RESET_PROTECT_UNTRACKED;
 144
 145         if (repo_read_index_unmerged(r) < 0) {
 146                 ret = error(_("could not read index"));
 147                 goto leave_reset_head;
 148         }
 149
 150         if (!reset_hard && !fill_tree_descriptor(r, &desc[nr++], &head_oid)) {
 151                 ret = error(_("failed to find tree of %s"),
 152                             oid_to_hex(&head_oid));
 153                 goto leave_reset_head;
 154         }
 155
 156         if (!fill_tree_descriptor(r, &desc[nr++], oid)) {
 157                 ret = error(_("failed to find tree of %s"), oid_to_hex(oid));
 158                 goto leave_reset_head;
 159         }
 160
 161         if (unpack_trees(nr, desc, &unpack_tree_opts)) {
 162                 ret = -1;
 163                 goto leave_reset_head;
 164         }
 165
 166         tree = parse_tree_indirect(oid);
 167         if (!tree) {
 168                 ret = error(_("unable to read tree (%s)"), oid_to_hex(oid));
 169                 goto leave_reset_head;
 170         }
 171
 172         prime_cache_tree(r, r->index, tree);
 173
 174         if (write_locked_index(r->index, &lock, COMMIT_LOCK) < 0) {
 175                 ret = error(_("could not write index"));
 176                 goto leave_reset_head;
 177         }
 178
 179         if (oid != &head_oid || update_orig_head || switch_to_branch)
 180                 ret = update_refs(opts, oid, head);
 181
 182 leave_reset_head:
 183         rollback_lock_file(&lock);
 184         clear_unpack_trees_porcelain(&unpack_tree_opts);
 185         while (nr)
 186                 free((void *)desc[--nr].buffer);
 187         return ret;
 188
 189 }