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-rw-r--r--unpack-trees.c1452
1 files changed, 1452 insertions, 0 deletions
diff --git a/unpack-trees.c b/unpack-trees.c
new file mode 100644
index 0000000..8cf0da3
--- /dev/null
+++ b/unpack-trees.c
@@ -0,0 +1,1452 @@
+#define NO_THE_INDEX_COMPATIBILITY_MACROS
+#include "cache.h"
+#include "dir.h"
+#include "tree.h"
+#include "tree-walk.h"
+#include "cache-tree.h"
+#include "unpack-trees.h"
+#include "progress.h"
+#include "refs.h"
+#include "attr.h"
+
+/*
+ * Error messages expected by scripts out of plumbing commands such as
+ * read-tree. Non-scripted Porcelain is not required to use these messages
+ * and in fact are encouraged to reword them to better suit their particular
+ * situation better. See how "git checkout" replaces not_uptodate_file to
+ * explain why it does not allow switching between branches when you have
+ * local changes, for example.
+ */
+static struct unpack_trees_error_msgs unpack_plumbing_errors = {
+ /* would_overwrite */
+ "Entry '%s' would be overwritten by merge. Cannot merge.",
+
+ /* not_uptodate_file */
+ "Entry '%s' not uptodate. Cannot merge.",
+
+ /* not_uptodate_dir */
+ "Updating '%s' would lose untracked files in it",
+
+ /* would_lose_untracked */
+ "Untracked working tree file '%s' would be %s by merge.",
+
+ /* bind_overlap */
+ "Entry '%s' overlaps with '%s'. Cannot bind.",
+
+ /* sparse_not_uptodate_file */
+ "Entry '%s' not uptodate. Cannot update sparse checkout.",
+
+ /* would_lose_orphaned */
+ "Working tree file '%s' would be %s by sparse checkout update.",
+};
+
+#define ERRORMSG(o,fld) \
+ ( ((o) && (o)->msgs.fld) \
+ ? ((o)->msgs.fld) \
+ : (unpack_plumbing_errors.fld) )
+
+static void add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
+ unsigned int set, unsigned int clear)
+{
+ unsigned int size = ce_size(ce);
+ struct cache_entry *new = xmalloc(size);
+
+ clear |= CE_HASHED | CE_UNHASHED;
+
+ memcpy(new, ce, size);
+ new->next = NULL;
+ new->ce_flags = (new->ce_flags & ~clear) | set;
+ add_index_entry(&o->result, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
+}
+
+/*
+ * Unlink the last component and schedule the leading directories for
+ * removal, such that empty directories get removed.
+ */
+static void unlink_entry(struct cache_entry *ce)
+{
+ if (has_symlink_or_noent_leading_path(ce->name, ce_namelen(ce)))
+ return;
+ if (remove_or_warn(ce->ce_mode, ce->name))
+ return;
+ schedule_dir_for_removal(ce->name, ce_namelen(ce));
+}
+
+static struct checkout state;
+static int check_updates(struct unpack_trees_options *o)
+{
+ unsigned cnt = 0, total = 0;
+ struct progress *progress = NULL;
+ struct index_state *index = &o->result;
+ int i;
+ int errs = 0;
+
+ if (o->update && o->verbose_update) {
+ for (total = cnt = 0; cnt < index->cache_nr; cnt++) {
+ struct cache_entry *ce = index->cache[cnt];
+ if (ce->ce_flags & (CE_UPDATE | CE_REMOVE | CE_WT_REMOVE))
+ total++;
+ }
+
+ progress = start_progress_delay("Checking out files",
+ total, 50, 1);
+ cnt = 0;
+ }
+
+ if (o->update)
+ git_attr_set_direction(GIT_ATTR_CHECKOUT, &o->result);
+ for (i = 0; i < index->cache_nr; i++) {
+ struct cache_entry *ce = index->cache[i];
+
+ if (ce->ce_flags & CE_WT_REMOVE) {
+ display_progress(progress, ++cnt);
+ if (o->update)
+ unlink_entry(ce);
+ continue;
+ }
+
+ if (ce->ce_flags & CE_REMOVE) {
+ display_progress(progress, ++cnt);
+ if (o->update)
+ unlink_entry(ce);
+ }
+ }
+ remove_marked_cache_entries(&o->result);
+ remove_scheduled_dirs();
+
+ for (i = 0; i < index->cache_nr; i++) {
+ struct cache_entry *ce = index->cache[i];
+
+ if (ce->ce_flags & CE_UPDATE) {
+ display_progress(progress, ++cnt);
+ ce->ce_flags &= ~CE_UPDATE;
+ if (o->update) {
+ errs |= checkout_entry(ce, &state, NULL);
+ }
+ }
+ }
+ stop_progress(&progress);
+ if (o->update)
+ git_attr_set_direction(GIT_ATTR_CHECKIN, NULL);
+ return errs != 0;
+}
+
+static int verify_uptodate_sparse(struct cache_entry *ce, struct unpack_trees_options *o);
+static int verify_absent_sparse(struct cache_entry *ce, const char *action, struct unpack_trees_options *o);
+
+static int will_have_skip_worktree(const struct cache_entry *ce, struct unpack_trees_options *o)
+{
+ const char *basename;
+
+ if (ce_stage(ce))
+ return 0;
+
+ basename = strrchr(ce->name, '/');
+ basename = basename ? basename+1 : ce->name;
+ return excluded_from_list(ce->name, ce_namelen(ce), basename, NULL, o->el) <= 0;
+}
+
+static int apply_sparse_checkout(struct cache_entry *ce, struct unpack_trees_options *o)
+{
+ int was_skip_worktree = ce_skip_worktree(ce);
+
+ if (will_have_skip_worktree(ce, o))
+ ce->ce_flags |= CE_SKIP_WORKTREE;
+ else
+ ce->ce_flags &= ~CE_SKIP_WORKTREE;
+
+ /*
+ * We only care about files getting into the checkout area
+ * If merge strategies want to remove some, go ahead, this
+ * flag will be removed eventually in unpack_trees() if it's
+ * outside checkout area.
+ */
+ if (ce->ce_flags & CE_REMOVE)
+ return 0;
+
+ if (!was_skip_worktree && ce_skip_worktree(ce)) {
+ /*
+ * If CE_UPDATE is set, verify_uptodate() must be called already
+ * also stat info may have lost after merged_entry() so calling
+ * verify_uptodate() again may fail
+ */
+ if (!(ce->ce_flags & CE_UPDATE) && verify_uptodate_sparse(ce, o))
+ return -1;
+ ce->ce_flags |= CE_WT_REMOVE;
+ }
+ if (was_skip_worktree && !ce_skip_worktree(ce)) {
+ if (verify_absent_sparse(ce, "overwritten", o))
+ return -1;
+ ce->ce_flags |= CE_UPDATE;
+ }
+ return 0;
+}
+
+static inline int call_unpack_fn(struct cache_entry **src, struct unpack_trees_options *o)
+{
+ int ret = o->fn(src, o);
+ if (ret > 0)
+ ret = 0;
+ return ret;
+}
+
+static void mark_ce_used(struct cache_entry *ce, struct unpack_trees_options *o)
+{
+ ce->ce_flags |= CE_UNPACKED;
+
+ if (o->cache_bottom < o->src_index->cache_nr &&
+ o->src_index->cache[o->cache_bottom] == ce) {
+ int bottom = o->cache_bottom;
+ while (bottom < o->src_index->cache_nr &&
+ o->src_index->cache[bottom]->ce_flags & CE_UNPACKED)
+ bottom++;
+ o->cache_bottom = bottom;
+ }
+}
+
+static void mark_all_ce_unused(struct index_state *index)
+{
+ int i;
+ for (i = 0; i < index->cache_nr; i++)
+ index->cache[i]->ce_flags &= ~CE_UNPACKED;
+}
+
+static int locate_in_src_index(struct cache_entry *ce,
+ struct unpack_trees_options *o)
+{
+ struct index_state *index = o->src_index;
+ int len = ce_namelen(ce);
+ int pos = index_name_pos(index, ce->name, len);
+ if (pos < 0)
+ pos = -1 - pos;
+ return pos;
+}
+
+/*
+ * We call unpack_index_entry() with an unmerged cache entry
+ * only in diff-index, and it wants a single callback. Skip
+ * the other unmerged entry with the same name.
+ */
+static void mark_ce_used_same_name(struct cache_entry *ce,
+ struct unpack_trees_options *o)
+{
+ struct index_state *index = o->src_index;
+ int len = ce_namelen(ce);
+ int pos;
+
+ for (pos = locate_in_src_index(ce, o); pos < index->cache_nr; pos++) {
+ struct cache_entry *next = index->cache[pos];
+ if (len != ce_namelen(next) ||
+ memcmp(ce->name, next->name, len))
+ break;
+ mark_ce_used(next, o);
+ }
+}
+
+static struct cache_entry *next_cache_entry(struct unpack_trees_options *o)
+{
+ const struct index_state *index = o->src_index;
+ int pos = o->cache_bottom;
+
+ while (pos < index->cache_nr) {
+ struct cache_entry *ce = index->cache[pos];
+ if (!(ce->ce_flags & CE_UNPACKED))
+ return ce;
+ pos++;
+ }
+ return NULL;
+}
+
+static void add_same_unmerged(struct cache_entry *ce,
+ struct unpack_trees_options *o)
+{
+ struct index_state *index = o->src_index;
+ int len = ce_namelen(ce);
+ int pos = index_name_pos(index, ce->name, len);
+
+ if (0 <= pos)
+ die("programming error in a caller of mark_ce_used_same_name");
+ for (pos = -pos - 1; pos < index->cache_nr; pos++) {
+ struct cache_entry *next = index->cache[pos];
+ if (len != ce_namelen(next) ||
+ memcmp(ce->name, next->name, len))
+ break;
+ add_entry(o, next, 0, 0);
+ mark_ce_used(next, o);
+ }
+}
+
+static int unpack_index_entry(struct cache_entry *ce,
+ struct unpack_trees_options *o)
+{
+ struct cache_entry *src[5] = { NULL };
+ int ret;
+
+ src[0] = ce;
+
+ mark_ce_used(ce, o);
+ if (ce_stage(ce)) {
+ if (o->skip_unmerged) {
+ add_entry(o, ce, 0, 0);
+ return 0;
+ }
+ }
+ ret = call_unpack_fn(src, o);
+ if (ce_stage(ce))
+ mark_ce_used_same_name(ce, o);
+ return ret;
+}
+
+static int find_cache_pos(struct traverse_info *, const struct name_entry *);
+
+static void restore_cache_bottom(struct traverse_info *info, int bottom)
+{
+ struct unpack_trees_options *o = info->data;
+
+ if (o->diff_index_cached)
+ return;
+ o->cache_bottom = bottom;
+}
+
+static int switch_cache_bottom(struct traverse_info *info)
+{
+ struct unpack_trees_options *o = info->data;
+ int ret, pos;
+
+ if (o->diff_index_cached)
+ return 0;
+ ret = o->cache_bottom;
+ pos = find_cache_pos(info->prev, &info->name);
+
+ if (pos < -1)
+ o->cache_bottom = -2 - pos;
+ else if (pos < 0)
+ o->cache_bottom = o->src_index->cache_nr;
+ return ret;
+}
+
+static int traverse_trees_recursive(int n, unsigned long dirmask, unsigned long df_conflicts, struct name_entry *names, struct traverse_info *info)
+{
+ int i, ret, bottom;
+ struct tree_desc t[MAX_UNPACK_TREES];
+ struct traverse_info newinfo;
+ struct name_entry *p;
+
+ p = names;
+ while (!p->mode)
+ p++;
+
+ newinfo = *info;
+ newinfo.prev = info;
+ newinfo.name = *p;
+ newinfo.pathlen += tree_entry_len(p->path, p->sha1) + 1;
+ newinfo.conflicts |= df_conflicts;
+
+ for (i = 0; i < n; i++, dirmask >>= 1) {
+ const unsigned char *sha1 = NULL;
+ if (dirmask & 1)
+ sha1 = names[i].sha1;
+ fill_tree_descriptor(t+i, sha1);
+ }
+
+ bottom = switch_cache_bottom(&newinfo);
+ ret = traverse_trees(n, t, &newinfo);
+ restore_cache_bottom(&newinfo, bottom);
+ return ret;
+}
+
+/*
+ * Compare the traverse-path to the cache entry without actually
+ * having to generate the textual representation of the traverse
+ * path.
+ *
+ * NOTE! This *only* compares up to the size of the traverse path
+ * itself - the caller needs to do the final check for the cache
+ * entry having more data at the end!
+ */
+static int do_compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
+{
+ int len, pathlen, ce_len;
+ const char *ce_name;
+
+ if (info->prev) {
+ int cmp = do_compare_entry(ce, info->prev, &info->name);
+ if (cmp)
+ return cmp;
+ }
+ pathlen = info->pathlen;
+ ce_len = ce_namelen(ce);
+
+ /* If ce_len < pathlen then we must have previously hit "name == directory" entry */
+ if (ce_len < pathlen)
+ return -1;
+
+ ce_len -= pathlen;
+ ce_name = ce->name + pathlen;
+
+ len = tree_entry_len(n->path, n->sha1);
+ return df_name_compare(ce_name, ce_len, S_IFREG, n->path, len, n->mode);
+}
+
+static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
+{
+ int cmp = do_compare_entry(ce, info, n);
+ if (cmp)
+ return cmp;
+
+ /*
+ * Even if the beginning compared identically, the ce should
+ * compare as bigger than a directory leading up to it!
+ */
+ return ce_namelen(ce) > traverse_path_len(info, n);
+}
+
+static int ce_in_traverse_path(const struct cache_entry *ce,
+ const struct traverse_info *info)
+{
+ if (!info->prev)
+ return 1;
+ if (do_compare_entry(ce, info->prev, &info->name))
+ return 0;
+ /*
+ * If ce (blob) is the same name as the path (which is a tree
+ * we will be descending into), it won't be inside it.
+ */
+ return (info->pathlen < ce_namelen(ce));
+}
+
+static struct cache_entry *create_ce_entry(const struct traverse_info *info, const struct name_entry *n, int stage)
+{
+ int len = traverse_path_len(info, n);
+ struct cache_entry *ce = xcalloc(1, cache_entry_size(len));
+
+ ce->ce_mode = create_ce_mode(n->mode);
+ ce->ce_flags = create_ce_flags(len, stage);
+ hashcpy(ce->sha1, n->sha1);
+ make_traverse_path(ce->name, info, n);
+
+ return ce;
+}
+
+static int unpack_nondirectories(int n, unsigned long mask,
+ unsigned long dirmask,
+ struct cache_entry **src,
+ const struct name_entry *names,
+ const struct traverse_info *info)
+{
+ int i;
+ struct unpack_trees_options *o = info->data;
+ unsigned long conflicts;
+
+ /* Do we have *only* directories? Nothing to do */
+ if (mask == dirmask && !src[0])
+ return 0;
+
+ conflicts = info->conflicts;
+ if (o->merge)
+ conflicts >>= 1;
+ conflicts |= dirmask;
+
+ /*
+ * Ok, we've filled in up to any potential index entry in src[0],
+ * now do the rest.
+ */
+ for (i = 0; i < n; i++) {
+ int stage;
+ unsigned int bit = 1ul << i;
+ if (conflicts & bit) {
+ src[i + o->merge] = o->df_conflict_entry;
+ continue;
+ }
+ if (!(mask & bit))
+ continue;
+ if (!o->merge)
+ stage = 0;
+ else if (i + 1 < o->head_idx)
+ stage = 1;
+ else if (i + 1 > o->head_idx)
+ stage = 3;
+ else
+ stage = 2;
+ src[i + o->merge] = create_ce_entry(info, names + i, stage);
+ }
+
+ if (o->merge)
+ return call_unpack_fn(src, o);
+
+ for (i = 0; i < n; i++)
+ if (src[i] && src[i] != o->df_conflict_entry)
+ add_entry(o, src[i], 0, 0);
+ return 0;
+}
+
+static int unpack_failed(struct unpack_trees_options *o, const char *message)
+{
+ discard_index(&o->result);
+ if (!o->gently) {
+ if (message)
+ return error("%s", message);
+ return -1;
+ }
+ return -1;
+}
+
+/* NEEDSWORK: give this a better name and share with tree-walk.c */
+static int name_compare(const char *a, int a_len,
+ const char *b, int b_len)
+{
+ int len = (a_len < b_len) ? a_len : b_len;
+ int cmp = memcmp(a, b, len);
+ if (cmp)
+ return cmp;
+ return (a_len - b_len);
+}
+
+/*
+ * The tree traversal is looking at name p. If we have a matching entry,
+ * return it. If name p is a directory in the index, do not return
+ * anything, as we will want to match it when the traversal descends into
+ * the directory.
+ */
+static int find_cache_pos(struct traverse_info *info,
+ const struct name_entry *p)
+{
+ int pos;
+ struct unpack_trees_options *o = info->data;
+ struct index_state *index = o->src_index;
+ int pfxlen = info->pathlen;
+ int p_len = tree_entry_len(p->path, p->sha1);
+
+ for (pos = o->cache_bottom; pos < index->cache_nr; pos++) {
+ struct cache_entry *ce = index->cache[pos];
+ const char *ce_name, *ce_slash;
+ int cmp, ce_len;
+
+ if (ce->ce_flags & CE_UNPACKED) {
+ /*
+ * cache_bottom entry is already unpacked, so
+ * we can never match it; don't check it
+ * again.
+ */
+ if (pos == o->cache_bottom)
+ ++o->cache_bottom;
+ continue;
+ }
+ if (!ce_in_traverse_path(ce, info))
+ continue;
+ ce_name = ce->name + pfxlen;
+ ce_slash = strchr(ce_name, '/');
+ if (ce_slash)
+ ce_len = ce_slash - ce_name;
+ else
+ ce_len = ce_namelen(ce) - pfxlen;
+ cmp = name_compare(p->path, p_len, ce_name, ce_len);
+ /*
+ * Exact match; if we have a directory we need to
+ * delay returning it.
+ */
+ if (!cmp)
+ return ce_slash ? -2 - pos : pos;
+ if (0 < cmp)
+ continue; /* keep looking */
+ /*
+ * ce_name sorts after p->path; could it be that we
+ * have files under p->path directory in the index?
+ * E.g. ce_name == "t-i", and p->path == "t"; we may
+ * have "t/a" in the index.
+ */
+ if (p_len < ce_len && !memcmp(ce_name, p->path, p_len) &&
+ ce_name[p_len] < '/')
+ continue; /* keep looking */
+ break;
+ }
+ return -1;
+}
+
+static struct cache_entry *find_cache_entry(struct traverse_info *info,
+ const struct name_entry *p)
+{
+ int pos = find_cache_pos(info, p);
+ struct unpack_trees_options *o = info->data;
+
+ if (0 <= pos)
+ return o->src_index->cache[pos];
+ else
+ return NULL;
+}
+
+static void debug_path(struct traverse_info *info)
+{
+ if (info->prev) {
+ debug_path(info->prev);
+ if (*info->prev->name.path)
+ putchar('/');
+ }
+ printf("%s", info->name.path);
+}
+
+static void debug_name_entry(int i, struct name_entry *n)
+{
+ printf("ent#%d %06o %s\n", i,
+ n->path ? n->mode : 0,
+ n->path ? n->path : "(missing)");
+}
+
+static void debug_unpack_callback(int n,
+ unsigned long mask,
+ unsigned long dirmask,
+ struct name_entry *names,
+ struct traverse_info *info)
+{
+ int i;
+ printf("* unpack mask %lu, dirmask %lu, cnt %d ",
+ mask, dirmask, n);
+ debug_path(info);
+ putchar('\n');
+ for (i = 0; i < n; i++)
+ debug_name_entry(i, names + i);
+}
+
+static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
+{
+ struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
+ struct unpack_trees_options *o = info->data;
+ const struct name_entry *p = names;
+
+ /* Find first entry with a real name (we could use "mask" too) */
+ while (!p->mode)
+ p++;
+
+ if (o->debug_unpack)
+ debug_unpack_callback(n, mask, dirmask, names, info);
+
+ /* Are we supposed to look at the index too? */
+ if (o->merge) {
+ while (1) {
+ int cmp;
+ struct cache_entry *ce;
+
+ if (o->diff_index_cached)
+ ce = next_cache_entry(o);
+ else
+ ce = find_cache_entry(info, p);
+
+ if (!ce)
+ break;
+ cmp = compare_entry(ce, info, p);
+ if (cmp < 0) {
+ if (unpack_index_entry(ce, o) < 0)
+ return unpack_failed(o, NULL);
+ continue;
+ }
+ if (!cmp) {
+ if (ce_stage(ce)) {
+ /*
+ * If we skip unmerged index
+ * entries, we'll skip this
+ * entry *and* the tree
+ * entries associated with it!
+ */
+ if (o->skip_unmerged) {
+ add_same_unmerged(ce, o);
+ return mask;
+ }
+ }
+ src[0] = ce;
+ }
+ break;
+ }
+ }
+
+ if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
+ return -1;
+
+ if (src[0]) {
+ if (ce_stage(src[0]))
+ mark_ce_used_same_name(src[0], o);
+ else
+ mark_ce_used(src[0], o);
+ }
+
+ /* Now handle any directories.. */
+ if (dirmask) {
+ unsigned long conflicts = mask & ~dirmask;
+ if (o->merge) {
+ conflicts <<= 1;
+ if (src[0])
+ conflicts |= 1;
+ }
+
+ /* special case: "diff-index --cached" looking at a tree */
+ if (o->diff_index_cached &&
+ n == 1 && dirmask == 1 && S_ISDIR(names->mode)) {
+ int matches;
+ matches = cache_tree_matches_traversal(o->src_index->cache_tree,
+ names, info);
+ /*
+ * Everything under the name matches; skip the
+ * entire hierarchy. diff_index_cached codepath
+ * special cases D/F conflicts in such a way that
+ * it does not do any look-ahead, so this is safe.
+ */
+ if (matches) {
+ o->cache_bottom += matches;
+ return mask;
+ }
+ }
+
+ if (traverse_trees_recursive(n, dirmask, conflicts,
+ names, info) < 0)
+ return -1;
+ return mask;
+ }
+
+ return mask;
+}
+
+/*
+ * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
+ * resulting index, -2 on failure to reflect the changes to the work tree.
+ */
+int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
+{
+ int i, ret;
+ static struct cache_entry *dfc;
+ struct exclude_list el;
+
+ if (len > MAX_UNPACK_TREES)
+ die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
+ memset(&state, 0, sizeof(state));
+ state.base_dir = "";
+ state.force = 1;
+ state.quiet = 1;
+ state.refresh_cache = 1;
+
+ memset(&el, 0, sizeof(el));
+ if (!core_apply_sparse_checkout || !o->update)
+ o->skip_sparse_checkout = 1;
+ if (!o->skip_sparse_checkout) {
+ if (add_excludes_from_file_to_list(git_path("info/sparse-checkout"), "", 0, NULL, &el, 0) < 0)
+ o->skip_sparse_checkout = 1;
+ else
+ o->el = &el;
+ }
+
+ memset(&o->result, 0, sizeof(o->result));
+ o->result.initialized = 1;
+ o->result.timestamp.sec = o->src_index->timestamp.sec;
+ o->result.timestamp.nsec = o->src_index->timestamp.nsec;
+ o->merge_size = len;
+ mark_all_ce_unused(o->src_index);
+
+ if (!dfc)
+ dfc = xcalloc(1, cache_entry_size(0));
+ o->df_conflict_entry = dfc;
+
+ if (len) {
+ const char *prefix = o->prefix ? o->prefix : "";
+ struct traverse_info info;
+
+ setup_traverse_info(&info, prefix);
+ info.fn = unpack_callback;
+ info.data = o;
+
+ if (o->prefix) {
+ /*
+ * Unpack existing index entries that sort before the
+ * prefix the tree is spliced into. Note that o->merge
+ * is always true in this case.
+ */
+ while (1) {
+ struct cache_entry *ce = next_cache_entry(o);
+ if (!ce)
+ break;
+ if (ce_in_traverse_path(ce, &info))
+ break;
+ if (unpack_index_entry(ce, o) < 0)
+ goto return_failed;
+ }
+ }
+
+ if (traverse_trees(len, t, &info) < 0)
+ goto return_failed;
+ }
+
+ /* Any left-over entries in the index? */
+ if (o->merge) {
+ while (1) {
+ struct cache_entry *ce = next_cache_entry(o);
+ if (!ce)
+ break;
+ if (unpack_index_entry(ce, o) < 0)
+ goto return_failed;
+ }
+ }
+ mark_all_ce_unused(o->src_index);
+
+ if (o->trivial_merges_only && o->nontrivial_merge) {
+ ret = unpack_failed(o, "Merge requires file-level merging");
+ goto done;
+ }
+
+ if (!o->skip_sparse_checkout) {
+ int empty_worktree = 1;
+ for (i = 0;i < o->result.cache_nr;i++) {
+ struct cache_entry *ce = o->result.cache[i];
+
+ if (apply_sparse_checkout(ce, o)) {
+ ret = -1;
+ goto done;
+ }
+ /*
+ * Merge strategies may set CE_UPDATE|CE_REMOVE outside checkout
+ * area as a result of ce_skip_worktree() shortcuts in
+ * verify_absent() and verify_uptodate(). Clear them.
+ */
+ if (ce_skip_worktree(ce))
+ ce->ce_flags &= ~(CE_UPDATE | CE_REMOVE);
+ else
+ empty_worktree = 0;
+
+ }
+ if (o->result.cache_nr && empty_worktree) {
+ ret = unpack_failed(o, "Sparse checkout leaves no entry on working directory");
+ goto done;
+ }
+ }
+
+ o->src_index = NULL;
+ ret = check_updates(o) ? (-2) : 0;
+ if (o->dst_index)
+ *o->dst_index = o->result;
+
+done:
+ for (i = 0;i < el.nr;i++)
+ free(el.excludes[i]);
+ if (el.excludes)
+ free(el.excludes);
+
+ return ret;
+
+return_failed:
+ mark_all_ce_unused(o->src_index);
+ ret = unpack_failed(o, NULL);
+ goto done;
+}
+
+/* Here come the merge functions */
+
+static int reject_merge(struct cache_entry *ce, struct unpack_trees_options *o)
+{
+ return error(ERRORMSG(o, would_overwrite), ce->name);
+}
+
+static int same(struct cache_entry *a, struct cache_entry *b)
+{
+ if (!!a != !!b)
+ return 0;
+ if (!a && !b)
+ return 1;
+ if ((a->ce_flags | b->ce_flags) & CE_CONFLICTED)
+ return 0;
+ return a->ce_mode == b->ce_mode &&
+ !hashcmp(a->sha1, b->sha1);
+}
+
+
+/*
+ * When a CE gets turned into an unmerged entry, we
+ * want it to be up-to-date
+ */
+static int verify_uptodate_1(struct cache_entry *ce,
+ struct unpack_trees_options *o,
+ const char *error_msg)
+{
+ struct stat st;
+
+ if (o->index_only || (!((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) && (o->reset || ce_uptodate(ce))))
+ return 0;
+
+ if (!lstat(ce->name, &st)) {
+ unsigned changed = ie_match_stat(o->src_index, ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
+ if (!changed)
+ return 0;
+ /*
+ * NEEDSWORK: the current default policy is to allow
+ * submodule to be out of sync wrt the supermodule
+ * index. This needs to be tightened later for
+ * submodules that are marked to be automatically
+ * checked out.
+ */
+ if (S_ISGITLINK(ce->ce_mode))
+ return 0;
+ errno = 0;
+ }
+ if (errno == ENOENT)
+ return 0;
+ return o->gently ? -1 :
+ error(error_msg, ce->name);
+}
+
+static int verify_uptodate(struct cache_entry *ce,
+ struct unpack_trees_options *o)
+{
+ if (!o->skip_sparse_checkout && will_have_skip_worktree(ce, o))
+ return 0;
+ return verify_uptodate_1(ce, o, ERRORMSG(o, not_uptodate_file));
+}
+
+static int verify_uptodate_sparse(struct cache_entry *ce,
+ struct unpack_trees_options *o)
+{
+ return verify_uptodate_1(ce, o, ERRORMSG(o, sparse_not_uptodate_file));
+}
+
+static void invalidate_ce_path(struct cache_entry *ce, struct unpack_trees_options *o)
+{
+ if (ce)
+ cache_tree_invalidate_path(o->src_index->cache_tree, ce->name);
+}
+
+/*
+ * Check that checking out ce->sha1 in subdir ce->name is not
+ * going to overwrite any working files.
+ *
+ * Currently, git does not checkout subprojects during a superproject
+ * checkout, so it is not going to overwrite anything.
+ */
+static int verify_clean_submodule(struct cache_entry *ce, const char *action,
+ struct unpack_trees_options *o)
+{
+ return 0;
+}
+
+static int verify_clean_subdirectory(struct cache_entry *ce, const char *action,
+ struct unpack_trees_options *o)
+{
+ /*
+ * we are about to extract "ce->name"; we would not want to lose
+ * anything in the existing directory there.
+ */
+ int namelen;
+ int i;
+ struct dir_struct d;
+ char *pathbuf;
+ int cnt = 0;
+ unsigned char sha1[20];
+
+ if (S_ISGITLINK(ce->ce_mode) &&
+ resolve_gitlink_ref(ce->name, "HEAD", sha1) == 0) {
+ /* If we are not going to update the submodule, then
+ * we don't care.
+ */
+ if (!hashcmp(sha1, ce->sha1))
+ return 0;
+ return verify_clean_submodule(ce, action, o);
+ }
+
+ /*
+ * First let's make sure we do not have a local modification
+ * in that directory.
+ */
+ namelen = strlen(ce->name);
+ for (i = locate_in_src_index(ce, o);
+ i < o->src_index->cache_nr;
+ i++) {
+ struct cache_entry *ce2 = o->src_index->cache[i];
+ int len = ce_namelen(ce2);
+ if (len < namelen ||
+ strncmp(ce->name, ce2->name, namelen) ||
+ ce2->name[namelen] != '/')
+ break;
+ /*
+ * ce2->name is an entry in the subdirectory to be
+ * removed.
+ */
+ if (!ce_stage(ce2)) {
+ if (verify_uptodate(ce2, o))
+ return -1;
+ add_entry(o, ce2, CE_REMOVE, 0);
+ mark_ce_used(ce2, o);
+ }
+ cnt++;
+ }
+
+ /*
+ * Then we need to make sure that we do not lose a locally
+ * present file that is not ignored.
+ */
+ pathbuf = xmalloc(namelen + 2);
+ memcpy(pathbuf, ce->name, namelen);
+ strcpy(pathbuf+namelen, "/");
+
+ memset(&d, 0, sizeof(d));
+ if (o->dir)
+ d.exclude_per_dir = o->dir->exclude_per_dir;
+ i = read_directory(&d, pathbuf, namelen+1, NULL);
+ if (i)
+ return o->gently ? -1 :
+ error(ERRORMSG(o, not_uptodate_dir), ce->name);
+ free(pathbuf);
+ return cnt;
+}
+
+/*
+ * This gets called when there was no index entry for the tree entry 'dst',
+ * but we found a file in the working tree that 'lstat()' said was fine,
+ * and we're on a case-insensitive filesystem.
+ *
+ * See if we can find a case-insensitive match in the index that also
+ * matches the stat information, and assume it's that other file!
+ */
+static int icase_exists(struct unpack_trees_options *o, struct cache_entry *dst, struct stat *st)
+{
+ struct cache_entry *src;
+
+ src = index_name_exists(o->src_index, dst->name, ce_namelen(dst), 1);
+ return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
+}
+
+/*
+ * We do not want to remove or overwrite a working tree file that
+ * is not tracked, unless it is ignored.
+ */
+static int verify_absent_1(struct cache_entry *ce, const char *action,
+ struct unpack_trees_options *o,
+ const char *error_msg)
+{
+ struct stat st;
+
+ if (o->index_only || o->reset || !o->update)
+ return 0;
+
+ if (has_symlink_or_noent_leading_path(ce->name, ce_namelen(ce)))
+ return 0;
+
+ if (!lstat(ce->name, &st)) {
+ int dtype = ce_to_dtype(ce);
+ struct cache_entry *result;
+
+ /*
+ * It may be that the 'lstat()' succeeded even though
+ * target 'ce' was absent, because there is an old
+ * entry that is different only in case..
+ *
+ * Ignore that lstat() if it matches.
+ */
+ if (ignore_case && icase_exists(o, ce, &st))
+ return 0;
+
+ if (o->dir && excluded(o->dir, ce->name, &dtype))
+ /*
+ * ce->name is explicitly excluded, so it is Ok to
+ * overwrite it.
+ */
+ return 0;
+ if (S_ISDIR(st.st_mode)) {
+ /*
+ * We are checking out path "foo" and
+ * found "foo/." in the working tree.
+ * This is tricky -- if we have modified
+ * files that are in "foo/" we would lose
+ * them.
+ */
+ if (verify_clean_subdirectory(ce, action, o) < 0)
+ return -1;
+ return 0;
+ }
+
+ /*
+ * The previous round may already have decided to
+ * delete this path, which is in a subdirectory that
+ * is being replaced with a blob.
+ */
+ result = index_name_exists(&o->result, ce->name, ce_namelen(ce), 0);
+ if (result) {
+ if (result->ce_flags & CE_REMOVE)
+ return 0;
+ }
+
+ return o->gently ? -1 :
+ error(ERRORMSG(o, would_lose_untracked), ce->name, action);
+ }
+ return 0;
+}
+static int verify_absent(struct cache_entry *ce, const char *action,
+ struct unpack_trees_options *o)
+{
+ if (!o->skip_sparse_checkout && will_have_skip_worktree(ce, o))
+ return 0;
+ return verify_absent_1(ce, action, o, ERRORMSG(o, would_lose_untracked));
+}
+
+static int verify_absent_sparse(struct cache_entry *ce, const char *action,
+ struct unpack_trees_options *o)
+{
+ return verify_absent_1(ce, action, o, ERRORMSG(o, would_lose_orphaned));
+}
+
+static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
+ struct unpack_trees_options *o)
+{
+ int update = CE_UPDATE;
+
+ if (!old) {
+ if (verify_absent(merge, "overwritten", o))
+ return -1;
+ invalidate_ce_path(merge, o);
+ } else if (!(old->ce_flags & CE_CONFLICTED)) {
+ /*
+ * See if we can re-use the old CE directly?
+ * That way we get the uptodate stat info.
+ *
+ * This also removes the UPDATE flag on a match; otherwise
+ * we will end up overwriting local changes in the work tree.
+ */
+ if (same(old, merge)) {
+ copy_cache_entry(merge, old);
+ update = 0;
+ } else {
+ if (verify_uptodate(old, o))
+ return -1;
+ if (ce_skip_worktree(old))
+ update |= CE_SKIP_WORKTREE;
+ invalidate_ce_path(old, o);
+ }
+ } else {
+ /*
+ * Previously unmerged entry left as an existence
+ * marker by read_index_unmerged();
+ */
+ invalidate_ce_path(old, o);
+ }
+
+ add_entry(o, merge, update, CE_STAGEMASK);
+ return 1;
+}
+
+static int deleted_entry(struct cache_entry *ce, struct cache_entry *old,
+ struct unpack_trees_options *o)
+{
+ /* Did it exist in the index? */
+ if (!old) {
+ if (verify_absent(ce, "removed", o))
+ return -1;
+ return 0;
+ }
+ if (!(old->ce_flags & CE_CONFLICTED) && verify_uptodate(old, o))
+ return -1;
+ add_entry(o, ce, CE_REMOVE, 0);
+ invalidate_ce_path(ce, o);
+ return 1;
+}
+
+static int keep_entry(struct cache_entry *ce, struct unpack_trees_options *o)
+{
+ add_entry(o, ce, 0, 0);
+ return 1;
+}
+
+#if DBRT_DEBUG
+static void show_stage_entry(FILE *o,
+ const char *label, const struct cache_entry *ce)
+{
+ if (!ce)
+ fprintf(o, "%s (missing)\n", label);
+ else
+ fprintf(o, "%s%06o %s %d\t%s\n",
+ label,
+ ce->ce_mode,
+ sha1_to_hex(ce->sha1),
+ ce_stage(ce),
+ ce->name);
+}
+#endif
+
+int threeway_merge(struct cache_entry **stages, struct unpack_trees_options *o)
+{
+ struct cache_entry *index;
+ struct cache_entry *head;
+ struct cache_entry *remote = stages[o->head_idx + 1];
+ int count;
+ int head_match = 0;
+ int remote_match = 0;
+
+ int df_conflict_head = 0;
+ int df_conflict_remote = 0;
+
+ int any_anc_missing = 0;
+ int no_anc_exists = 1;
+ int i;
+
+ for (i = 1; i < o->head_idx; i++) {
+ if (!stages[i] || stages[i] == o->df_conflict_entry)
+ any_anc_missing = 1;
+ else
+ no_anc_exists = 0;
+ }
+
+ index = stages[0];
+ head = stages[o->head_idx];
+
+ if (head == o->df_conflict_entry) {
+ df_conflict_head = 1;
+ head = NULL;
+ }
+
+ if (remote == o->df_conflict_entry) {
+ df_conflict_remote = 1;
+ remote = NULL;
+ }
+
+ /*
+ * First, if there's a #16 situation, note that to prevent #13
+ * and #14.
+ */
+ if (!same(remote, head)) {
+ for (i = 1; i < o->head_idx; i++) {
+ if (same(stages[i], head)) {
+ head_match = i;
+ }
+ if (same(stages[i], remote)) {
+ remote_match = i;
+ }
+ }
+ }
+
+ /*
+ * We start with cases where the index is allowed to match
+ * something other than the head: #14(ALT) and #2ALT, where it
+ * is permitted to match the result instead.
+ */
+ /* #14, #14ALT, #2ALT */
+ if (remote && !df_conflict_head && head_match && !remote_match) {
+ if (index && !same(index, remote) && !same(index, head))
+ return o->gently ? -1 : reject_merge(index, o);
+ return merged_entry(remote, index, o);
+ }
+ /*
+ * If we have an entry in the index cache, then we want to
+ * make sure that it matches head.
+ */
+ if (index && !same(index, head))
+ return o->gently ? -1 : reject_merge(index, o);
+
+ if (head) {
+ /* #5ALT, #15 */
+ if (same(head, remote))
+ return merged_entry(head, index, o);
+ /* #13, #3ALT */
+ if (!df_conflict_remote && remote_match && !head_match)
+ return merged_entry(head, index, o);
+ }
+
+ /* #1 */
+ if (!head && !remote && any_anc_missing)
+ return 0;
+
+ /*
+ * Under the "aggressive" rule, we resolve mostly trivial
+ * cases that we historically had git-merge-one-file resolve.
+ */
+ if (o->aggressive) {
+ int head_deleted = !head;
+ int remote_deleted = !remote;
+ struct cache_entry *ce = NULL;
+
+ if (index)
+ ce = index;
+ else if (head)
+ ce = head;
+ else if (remote)
+ ce = remote;
+ else {
+ for (i = 1; i < o->head_idx; i++) {
+ if (stages[i] && stages[i] != o->df_conflict_entry) {
+ ce = stages[i];
+ break;
+ }
+ }
+ }
+
+ /*
+ * Deleted in both.
+ * Deleted in one and unchanged in the other.
+ */
+ if ((head_deleted && remote_deleted) ||
+ (head_deleted && remote && remote_match) ||
+ (remote_deleted && head && head_match)) {
+ if (index)
+ return deleted_entry(index, index, o);
+ if (ce && !head_deleted) {
+ if (verify_absent(ce, "removed", o))
+ return -1;
+ }
+ return 0;
+ }
+ /*
+ * Added in both, identically.
+ */
+ if (no_anc_exists && head && remote && same(head, remote))
+ return merged_entry(head, index, o);
+
+ }
+
+ /* Below are "no merge" cases, which require that the index be
+ * up-to-date to avoid the files getting overwritten with
+ * conflict resolution files.
+ */
+ if (index) {
+ if (verify_uptodate(index, o))
+ return -1;
+ }
+
+ o->nontrivial_merge = 1;
+
+ /* #2, #3, #4, #6, #7, #9, #10, #11. */
+ count = 0;
+ if (!head_match || !remote_match) {
+ for (i = 1; i < o->head_idx; i++) {
+ if (stages[i] && stages[i] != o->df_conflict_entry) {
+ keep_entry(stages[i], o);
+ count++;
+ break;
+ }
+ }
+ }
+#if DBRT_DEBUG
+ else {
+ fprintf(stderr, "read-tree: warning #16 detected\n");
+ show_stage_entry(stderr, "head ", stages[head_match]);
+ show_stage_entry(stderr, "remote ", stages[remote_match]);
+ }
+#endif
+ if (head) { count += keep_entry(head, o); }
+ if (remote) { count += keep_entry(remote, o); }
+ return count;
+}
+
+/*
+ * Two-way merge.
+ *
+ * The rule is to "carry forward" what is in the index without losing
+ * information across a "fast-forward", favoring a successful merge
+ * over a merge failure when it makes sense. For details of the
+ * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
+ *
+ */
+int twoway_merge(struct cache_entry **src, struct unpack_trees_options *o)
+{
+ struct cache_entry *current = src[0];
+ struct cache_entry *oldtree = src[1];
+ struct cache_entry *newtree = src[2];
+
+ if (o->merge_size != 2)
+ return error("Cannot do a twoway merge of %d trees",
+ o->merge_size);
+
+ if (oldtree == o->df_conflict_entry)
+ oldtree = NULL;
+ if (newtree == o->df_conflict_entry)
+ newtree = NULL;
+
+ if (current) {
+ if ((!oldtree && !newtree) || /* 4 and 5 */
+ (!oldtree && newtree &&
+ same(current, newtree)) || /* 6 and 7 */
+ (oldtree && newtree &&
+ same(oldtree, newtree)) || /* 14 and 15 */
+ (oldtree && newtree &&
+ !same(oldtree, newtree) && /* 18 and 19 */
+ same(current, newtree))) {
+ return keep_entry(current, o);
+ }
+ else if (oldtree && !newtree && same(current, oldtree)) {
+ /* 10 or 11 */
+ return deleted_entry(oldtree, current, o);
+ }
+ else if (oldtree && newtree &&
+ same(current, oldtree) && !same(current, newtree)) {
+ /* 20 or 21 */
+ return merged_entry(newtree, current, o);
+ }
+ else {
+ /* all other failures */
+ if (oldtree)
+ return o->gently ? -1 : reject_merge(oldtree, o);
+ if (current)
+ return o->gently ? -1 : reject_merge(current, o);
+ if (newtree)
+ return o->gently ? -1 : reject_merge(newtree, o);
+ return -1;
+ }
+ }
+ else if (newtree) {
+ if (oldtree && !o->initial_checkout) {
+ /*
+ * deletion of the path was staged;
+ */
+ if (same(oldtree, newtree))
+ return 1;
+ return reject_merge(oldtree, o);
+ }
+ return merged_entry(newtree, current, o);
+ }
+ return deleted_entry(oldtree, current, o);
+}
+
+/*
+ * Bind merge.
+ *
+ * Keep the index entries at stage0, collapse stage1 but make sure
+ * stage0 does not have anything there.
+ */
+int bind_merge(struct cache_entry **src,
+ struct unpack_trees_options *o)
+{
+ struct cache_entry *old = src[0];
+ struct cache_entry *a = src[1];
+
+ if (o->merge_size != 1)
+ return error("Cannot do a bind merge of %d trees\n",
+ o->merge_size);
+ if (a && old)
+ return o->gently ? -1 :
+ error(ERRORMSG(o, bind_overlap), a->name, old->name);
+ if (!a)
+ return keep_entry(old, o);
+ else
+ return merged_entry(a, NULL, o);
+}
+
+/*
+ * One-way merge.
+ *
+ * The rule is:
+ * - take the stat information from stage0, take the data from stage1
+ */
+int oneway_merge(struct cache_entry **src, struct unpack_trees_options *o)
+{
+ struct cache_entry *old = src[0];
+ struct cache_entry *a = src[1];
+
+ if (o->merge_size != 1)
+ return error("Cannot do a oneway merge of %d trees",
+ o->merge_size);
+
+ if (!a || a == o->df_conflict_entry)
+ return deleted_entry(old, old, o);
+
+ if (old && same(old, a)) {
+ int update = 0;
+ if (o->reset && !ce_uptodate(old) && !ce_skip_worktree(old)) {
+ struct stat st;
+ if (lstat(old->name, &st) ||
+ ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
+ update |= CE_UPDATE;
+ }
+ add_entry(o, old, update, 0);
+ return 0;
+ }
+ return merged_entry(a, old, o);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-27 04:16:07 +0000