#include "cache.h"
#include "tree.h"
#include "tree-walk.h"
+#include "cache-tree.h"
#include "unpack-trees.h"
+#define DBRT_DEBUG 1
+
struct tree_entry_list {
struct tree_entry_list *next;
unsigned directory : 1;
struct tree_entry_list *ret = NULL;
struct tree_entry_list **list_p = &ret;
+ if (!tree->object.parsed)
+ parse_tree(tree);
+
desc.buf = tree->buffer;
desc.size = tree->size;
any_files = 1;
- memcpy(ce->sha1, posns[i]->sha1, 20);
+ hashcpy(ce->sha1, posns[i]->sha1);
src[i + o->merge] = ce;
subposns[i] = df_conflict_list;
posns[i] = posns[i]->next;
}
}
-static volatile int progress_update = 0;
+static volatile sig_atomic_t progress_update;
static void progress_interval(int signum)
{
memset(&df_conflict_list, 0, sizeof(df_conflict_list));
df_conflict_list.next = &df_conflict_list;
+ memset(&state, 0, sizeof(state));
state.base_dir = "";
state.force = 1;
state.quiet = 1;
state.refresh_cache = 1;
o->merge_size = len;
+ memset(&df_conflict_entry, 0, sizeof(df_conflict_entry));
o->df_conflict_entry = &df_conflict_entry;
if (len) {
check_updates(active_cache, active_nr, o);
return 0;
}
+
+/* Here come the merge functions */
+
+static void reject_merge(struct cache_entry *ce)
+{
+ die("Entry '%s' would be overwritten by merge. Cannot merge.",
+ ce->name);
+}
+
+static int same(struct cache_entry *a, struct cache_entry *b)
+{
+ if (!!a != !!b)
+ return 0;
+ if (!a && !b)
+ return 1;
+ 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 void verify_uptodate(struct cache_entry *ce,
+ struct unpack_trees_options *o)
+{
+ struct stat st;
+
+ if (o->index_only || o->reset)
+ return;
+
+ if (!lstat(ce->name, &st)) {
+ unsigned changed = ce_match_stat(ce, &st, 1);
+ if (!changed)
+ return;
+ errno = 0;
+ }
+ if (o->reset) {
+ ce->ce_flags |= htons(CE_UPDATE);
+ return;
+ }
+ if (errno == ENOENT)
+ return;
+ die("Entry '%s' not uptodate. Cannot merge.", ce->name);
+}
+
+static void invalidate_ce_path(struct cache_entry *ce)
+{
+ if (ce)
+ cache_tree_invalidate_path(active_cache_tree, ce->name);
+}
+
+/*
+ * We do not want to remove or overwrite a working tree file that
+ * is not tracked.
+ */
+static void verify_absent(const char *path, const char *action,
+ struct unpack_trees_options *o)
+{
+ struct stat st;
+
+ if (o->index_only || o->reset || !o->update)
+ return;
+ if (!lstat(path, &st))
+ die("Untracked working tree file '%s' "
+ "would be %s by merge.", path, action);
+}
+
+static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
+ struct unpack_trees_options *o)
+{
+ merge->ce_flags |= htons(CE_UPDATE);
+ if (old) {
+ /*
+ * 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.
+ */
+ if (same(old, merge)) {
+ *merge = *old;
+ } else {
+ verify_uptodate(old, o);
+ invalidate_ce_path(old);
+ }
+ }
+ else {
+ verify_absent(merge->name, "overwritten", o);
+ invalidate_ce_path(merge);
+ }
+
+ merge->ce_flags &= ~htons(CE_STAGEMASK);
+ add_cache_entry(merge, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
+ return 1;
+}
+
+static int deleted_entry(struct cache_entry *ce, struct cache_entry *old,
+ struct unpack_trees_options *o)
+{
+ if (old)
+ verify_uptodate(old, o);
+ else
+ verify_absent(ce->name, "removed", o);
+ ce->ce_mode = 0;
+ add_cache_entry(ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
+ invalidate_ce_path(ce);
+ return 1;
+}
+
+static int keep_entry(struct cache_entry *ce)
+{
+ add_cache_entry(ce, ADD_CACHE_OK_TO_ADD);
+ 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,
+ ntohl(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;
+ const char *path = NULL;
+
+ 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])
+ any_anc_missing = 1;
+ else {
+ if (!path)
+ path = stages[i]->name;
+ 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;
+ }
+
+ if (!path && index)
+ path = index->name;
+ if (!path && head)
+ path = head->name;
+ if (!path && remote)
+ path = remote->name;
+
+ /* 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))
+ reject_merge(index);
+ 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)) {
+ reject_merge(index);
+ }
+
+ 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 new "aggressive" rule, we resolve mostly trivial
+ * cases that we historically had git-merge-one-file resolve.
+ */
+ if (o->aggressive) {
+ int head_deleted = !head && !df_conflict_head;
+ int remote_deleted = !remote && !df_conflict_remote;
+ /*
+ * 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);
+ else if (path)
+ verify_absent(path, "removed", o);
+ 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) {
+ verify_uptodate(index, o);
+ }
+ else if (path)
+ verify_absent(path, "overwritten", o);
+
+ o->nontrivial_merge = 1;
+
+ /* #2, #3, #4, #6, #7, #9, #11. */
+ count = 0;
+ if (!head_match || !remote_match) {
+ for (i = 1; i < o->head_idx; i++) {
+ if (stages[i]) {
+ keep_entry(stages[i]);
+ 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); }
+ if (remote) { count += keep_entry(remote); }
+ 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], *newtree = src[2];
+
+ if (o->merge_size != 2)
+ return error("Cannot do a twoway merge of %d trees",
+ o->merge_size);
+
+ 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);
+ }
+ 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)
+ reject_merge(oldtree);
+ if (current)
+ reject_merge(current);
+ if (newtree)
+ reject_merge(newtree);
+ return -1;
+ }
+ }
+ else if (newtree)
+ return merged_entry(newtree, current, o);
+ else
+ 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)
+ die("Entry '%s' overlaps. Cannot bind.", a->name);
+ if (!a)
+ return keep_entry(old);
+ 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)
+ return deleted_entry(old, old, o);
+ if (old && same(old, a)) {
+ if (o->reset) {
+ struct stat st;
+ if (lstat(old->name, &st) ||
+ ce_match_stat(old, &st, 1))
+ old->ce_flags |= htons(CE_UPDATE);
+ }
+ return keep_entry(old);
+ }
+ return merged_entry(a, old, o);
+}