Junio C HamanoThe new notation is a short-hand for <name> followed by <num> caret ('^') characters. E.g. "master:4" is the fourth generation ancestor of the current "master" branch head, following the first parents; same as "master^^^^" but a bit more readable.
This will be used in the updated "git show-branch" command.
Signed-off-by: Junio C Hamano <junkio@cox.net>
---
sha1_name.c | 41 +++++++++++++++++++++++++++++++++++++++++ 1 files changed, 41 insertions(+), 0 deletions(-)
3a371474bc20e192b0e9d3b48fb7c84ca107b818
Show changes to sha1_name.c +41 −0
diff --git a/sha1_name.c b/sha1_name.c --- a/sha1_name.c +++ b/sha1_name.c @@ -191,9 +191,29 @@ static int get_parent(const char *name, return -1; } +static int get_nth_ancestor(const char *name, int len, + unsigned char *result, int generation) +{ + unsigned char sha1[20]; + int ret = get_sha1_1(name, len, sha1); + if (ret) + return ret; + + while (generation--) { + struct commit *commit = lookup_commit_reference(sha1); + + if (!commit || parse_commit(commit) || !commit->parents) + return -1; + memcpy(sha1, commit->parents->item->object.sha1, 20); + } + memcpy(result, sha1, 20); + return 0; +} + static int get_sha1_1(const char *name, int len, unsigned char *sha1) { int parent, ret; + const char *cp; /* foo^[0-9] or foo^ (== foo^1); we do not do more than 9 parents. */ if (len > 2 && name[len-2] == '^' && @@ -210,6 +230,27 @@ static int get_sha1_1(const char *name, if (parent >= 0) return get_parent(name, len, sha1, parent); + /* name:3 is name^^^, + * name:12 is name^^^^^^^^^^^^, and + * name: is name + */ + parent = 0; + for (cp = name + len - 1; name <= cp; cp--) { + int ch = *cp; + if ('0' <= ch && ch <= '9') + continue; + if (ch != ':') + parent = -1; + break; + } + if (!parent && *cp == ':') { + int len1 = cp - name; + cp++; + while (cp < name + len) + parent = parent * 10 + *cp++ - '0'; + return get_nth_ancestor(name, len1, sha1, parent); + } + ret = get_sha1_basic(name, len, sha1); if (!ret) return 0;
