reset.c

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