reset.c

   1 #include "git-compat-util.h"
   2 #include "cache-tree.h"
   3 #include "lockfile.h"
   4 #include "refs.h"
   5 #include "reset.h"
   6 #include "run-command.h"
   7 #include "tree-walk.h"
   8 #include "tree.h"
   9 #include "unpack-trees.h"
  10 #include "hook.h"
  11
  12 int reset_head(struct repository *r, struct object_id *oid, const char *action,
  13                const char *switch_to_branch, unsigned flags,
  14                const char *reflog_orig_head, const char *reflog_head,
  15                const char *default_reflog_action)
  16 {
  17         unsigned detach_head = flags & RESET_HEAD_DETACH;
  18         unsigned reset_hard = flags & RESET_HEAD_HARD;
  19         unsigned run_hook = flags & RESET_HEAD_RUN_POST_CHECKOUT_HOOK;
  20         unsigned refs_only = flags & RESET_HEAD_REFS_ONLY;
  21         unsigned update_orig_head = flags & RESET_ORIG_HEAD;
  22         struct object_id head_oid;
  23         struct tree_desc desc[2] = { { NULL }, { NULL } };
  24         struct lock_file lock = LOCK_INIT;
  25         struct unpack_trees_options unpack_tree_opts = { 0 };
  26         struct tree *tree;
  27         const char *reflog_action;
  28         struct strbuf msg = STRBUF_INIT;
  29         size_t prefix_len;
  30         struct object_id *orig = NULL, oid_orig,
  31                 *old_orig = NULL, oid_old_orig;
  32         int ret = 0, nr = 0;
  33
  34         if (switch_to_branch && !starts_with(switch_to_branch, "refs/"))
  35                 BUG("Not a fully qualified branch: '%s'", switch_to_branch);
  36
  37         if (!refs_only && repo_hold_locked_index(r, &lock, LOCK_REPORT_ON_ERROR) < 0) {
  38                 ret = -1;
  39                 goto leave_reset_head;
  40         }
  41
  42         if ((!oid || !reset_hard) && get_oid("HEAD", &head_oid)) {
  43                 ret = error(_("could not determine HEAD revision"));
  44                 goto leave_reset_head;
  45         }
  46
  47         if (!oid)
  48                 oid = &head_oid;
  49
  50         if (refs_only)
  51                 goto reset_head_refs;
  52
  53         setup_unpack_trees_porcelain(&unpack_tree_opts, action);
  54         unpack_tree_opts.head_idx = 1;
  55         unpack_tree_opts.src_index = r->index;
  56         unpack_tree_opts.dst_index = r->index;
  57         unpack_tree_opts.fn = reset_hard ? oneway_merge : twoway_merge;
  58         unpack_tree_opts.update = 1;
  59         unpack_tree_opts.merge = 1;
  60         unpack_tree_opts.preserve_ignored = 0; /* FIXME: !overwrite_ignore */
  61         init_checkout_metadata(&unpack_tree_opts.meta, switch_to_branch, oid, NULL);
  62         if (!detach_head)
  63                 unpack_tree_opts.reset = UNPACK_RESET_PROTECT_UNTRACKED;
  64
  65         if (repo_read_index_unmerged(r) < 0) {
  66                 ret = error(_("could not read index"));
  67                 goto leave_reset_head;
  68         }
  69
  70         if (!reset_hard && !fill_tree_descriptor(r, &desc[nr++], &head_oid)) {
  71                 ret = error(_("failed to find tree of %s"),
  72                             oid_to_hex(&head_oid));
  73                 goto leave_reset_head;
  74         }
  75
  76         if (!fill_tree_descriptor(r, &desc[nr++], oid)) {
  77                 ret = error(_("failed to find tree of %s"), oid_to_hex(oid));
  78                 goto leave_reset_head;
  79         }
  80
  81         if (unpack_trees(nr, desc, &unpack_tree_opts)) {
  82                 ret = -1;
  83                 goto leave_reset_head;
  84         }
  85
  86         tree = parse_tree_indirect(oid);
  87         prime_cache_tree(r, r->index, tree);
  88
  89         if (write_locked_index(r->index, &lock, COMMIT_LOCK) < 0) {
  90                 ret = error(_("could not write index"));
  91                 goto leave_reset_head;
  92         }
  93
  94 reset_head_refs:
  95         reflog_action = getenv(GIT_REFLOG_ACTION_ENVIRONMENT);
  96         strbuf_addf(&msg, "%s: ", reflog_action ? reflog_action : default_reflog_action);
  97         prefix_len = msg.len;
  98
  99         if (update_orig_head) {
 100                 if (!get_oid("ORIG_HEAD", &oid_old_orig))
 101                         old_orig = &oid_old_orig;
 102                 if (!get_oid("HEAD", &oid_orig)) {
 103                         orig = &oid_orig;
 104                         if (!reflog_orig_head) {
 105                                 strbuf_addstr(&msg, "updating ORIG_HEAD");
 106                                 reflog_orig_head = msg.buf;
 107                         }
 108                         update_ref(reflog_orig_head, "ORIG_HEAD", orig,
 109                                    old_orig, 0, UPDATE_REFS_MSG_ON_ERR);
 110                 } else if (old_orig)
 111                         delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
 112         }
 113
 114         if (!reflog_head) {
 115                 strbuf_setlen(&msg, prefix_len);
 116                 strbuf_addstr(&msg, "updating HEAD");
 117                 reflog_head = msg.buf;
 118         }
 119         if (!switch_to_branch)
 120                 ret = update_ref(reflog_head, "HEAD", oid, orig,
 121                                  detach_head ? REF_NO_DEREF : 0,
 122                                  UPDATE_REFS_MSG_ON_ERR);
 123         else {
 124                 ret = update_ref(reflog_head, switch_to_branch, oid,
 125                                  NULL, 0, UPDATE_REFS_MSG_ON_ERR);
 126                 if (!ret)
 127                         ret = create_symref("HEAD", switch_to_branch,
 128                                             reflog_head);
 129         }
 130         if (run_hook)
 131                 run_hooks_l("post-checkout",
 132                             oid_to_hex(orig ? orig : null_oid()),
 133                             oid_to_hex(oid), "1", NULL);
 134
 135 leave_reset_head:
 136         strbuf_release(&msg);
 137         rollback_lock_file(&lock);
 138         clear_unpack_trees_porcelain(&unpack_tree_opts);
 139         while (nr)
 140                 free((void *)desc[--nr].buffer);
 141         return ret;
 142
 143 }