diff options
| -rw-r--r-- | Documentation/rev-list-options.txt | 10 | ||||
| -rw-r--r-- | revision.c | 171 | ||||
| -rw-r--r-- | revision.h | 1 |
3 files changed, 160 insertions, 22 deletions
diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt index 3aa38097e6..ee6822a85d 100644 --- a/Documentation/rev-list-options.txt +++ b/Documentation/rev-list-options.txt @@ -193,12 +193,18 @@ endif::git-rev-list[] --full-history:: - Show also parts of history irrelevant to current state of a given - path. This turns off history simplification, which removed merges + Show also parts of history irrelevant to current state of given + paths. This turns off history simplification, which removed merges which didn't change anything at all at some child. It will still actually simplify away merges that didn't change anything at all into either child. +--simplify-merges:: + + Simplify away commits that did not change the given paths, similar + to `--full-history`, and further remove merges none of whose + parent history changes the given paths. + --no-merges:: Do not print commits with more than one parent. diff --git a/revision.c b/revision.c index 71f0bea899..662d66be7e 100644 --- a/revision.c +++ b/revision.c @@ -1045,6 +1045,11 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg } else if (!strcmp(arg, "--topo-order")) { revs->lifo = 1; revs->topo_order = 1; + } else if (!strcmp(arg, "--simplify-merges")) { + revs->simplify_merges = 1; + revs->rewrite_parents = 1; + revs->simplify_history = 0; + revs->limited = 1; } else if (!strcmp(arg, "--date-order")) { revs->lifo = 0; revs->topo_order = 1; @@ -1378,6 +1383,150 @@ static void add_child(struct rev_info *revs, struct commit *parent, struct commi l->next = add_decoration(&revs->children, &parent->object, l); } +static int remove_duplicate_parents(struct commit *commit) +{ + struct commit_list **pp, *p; + int surviving_parents; + + /* Examine existing parents while marking ones we have seen... */ + pp = &commit->parents; + while ((p = *pp) != NULL) { + struct commit *parent = p->item; + if (parent->object.flags & TMP_MARK) { + *pp = p->next; + continue; + } + parent->object.flags |= TMP_MARK; + pp = &p->next; + } + /* count them while clearing the temporary mark */ + surviving_parents = 0; + for (p = commit->parents; p; p = p->next) { + p->item->object.flags &= ~TMP_MARK; + surviving_parents++; + } + return surviving_parents; +} + +static struct commit_list **simplify_one(struct commit *commit, struct commit_list **tail) +{ + struct commit_list *p; + int cnt; + + /* + * We store which commit each one simplifies to in its util field. + * Have we handled this one? + */ + if (commit->util) + return tail; + + /* + * An UNINTERESTING commit simplifies to itself, so does a + * root commit. We do not rewrite parents of such commit + * anyway. + */ + if ((commit->object.flags & UNINTERESTING) || !commit->parents) { + commit->util = commit; + return tail; + } + + /* + * Do we know what commit all of our parents should be rewritten to? + * Otherwise we are not ready to rewrite this one yet. + */ + for (cnt = 0, p = commit->parents; p; p = p->next) { + if (!p->item->util) { + tail = &commit_list_insert(p->item, tail)->next; + cnt++; + } + } + if (cnt) + return tail; + + /* + * Rewrite our list of parents. + */ + for (p = commit->parents; p; p = p->next) + p->item = p->item->util; + cnt = remove_duplicate_parents(commit); + + /* + * It is possible that we are a merge and one side branch + * does not have any commit that touches the given paths; + * in such a case, the immediate parents will be rewritten + * to different commits. + * + * o----X X: the commit we are looking at; + * / / o: a commit that touches the paths; + * ---o----' + * + * Further reduce the parents by removing redundant parents. + */ + if (1 < cnt) { + struct commit_list *h = reduce_heads(commit->parents); + cnt = commit_list_count(h); + free_commit_list(commit->parents); + commit->parents = h; + } + + /* + * A commit simplifies to itself if it is a root, if it is + * UNINTERESTING, if it touches the given paths, or if it is a + * merge and its parents simplifies to more than one commits + * (the first two cases are already handled at the beginning of + * this function). + * + * Otherwise, it simplifies to what its sole parent simplifies to. + */ + if (!cnt || + (commit->object.flags & UNINTERESTING) || + !(commit->object.flags & TREESAME) || + (1 < cnt)) + commit->util = commit; + else + commit->util = commit->parents->item->util; + return tail; +} + +static void simplify_merges(struct rev_info *revs) +{ + struct commit_list *list; + struct commit_list *yet_to_do, **tail; + + /* feed the list reversed */ + yet_to_do = NULL; + for (list = revs->commits; list; list = list->next) + commit_list_insert(list->item, &yet_to_do); + while (yet_to_do) { + list = yet_to_do; + yet_to_do = NULL; + tail = &yet_to_do; + while (list) { + struct commit *commit = list->item; + struct commit_list *next = list->next; + free(list); + list = next; + tail = simplify_one(commit, tail); + } + } + + /* clean up the result, removing the simplified ones */ + list = revs->commits; + revs->commits = NULL; + tail = &revs->commits; + while (list) { + struct commit *commit = list->item; + struct commit_list *next = list->next; + free(list); + list = next; + if (commit->util == commit) + tail = &commit_list_insert(commit, tail)->next; + } + + /* sort topologically at the end */ + sort_in_topological_order(&revs->commits, revs->lifo); +} + static void set_children(struct rev_info *revs) { struct commit_list *l; @@ -1418,6 +1567,8 @@ int prepare_revision_walk(struct rev_info *revs) return -1; if (revs->topo_order) sort_in_topological_order(&revs->commits, revs->lifo); + if (revs->simplify_merges) + simplify_merges(revs); if (revs->children.name) set_children(revs); return 0; @@ -1450,26 +1601,6 @@ static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp } } -static void remove_duplicate_parents(struct commit *commit) -{ - struct commit_list **pp, *p; - - /* Examine existing parents while marking ones we have seen... */ - pp = &commit->parents; - while ((p = *pp) != NULL) { - struct commit *parent = p->item; - if (parent->object.flags & TMP_MARK) { - *pp = p->next; - continue; - } - parent->object.flags |= TMP_MARK; - pp = &p->next; - } - /* ... and clear the temporary mark */ - for (p = commit->parents; p; p = p->next) - p->item->object.flags &= ~TMP_MARK; -} - static int rewrite_parents(struct rev_info *revs, struct commit *commit) { struct commit_list **pp = &commit->parents; diff --git a/revision.h b/revision.h index f64e8ce7ff..dfa06b5210 100644 --- a/revision.h +++ b/revision.h @@ -41,6 +41,7 @@ struct rev_info { simplify_history:1, lifo:1, topo_order:1, + simplify_merges:1, tag_objects:1, tree_objects:1, blob_objects:1, |