From 4228e8bc989c6cac1c47faece720faa06531281f Mon Sep 17 00:00:00 2001 From: Christian Couder Date: Sat, 19 Jul 2014 17:01:08 +0200 Subject: [PATCH] replace: add --graft option The usage string for this option is: git replace [-f] --graft [...] First we create a new commit that is the same as except that its parents are [...] Then we create a replace ref that replace with the commit we just created. With this new option, it should be straightforward to convert grafts to replace refs. Signed-off-by: Christian Couder Signed-off-by: Junio C Hamano --- builtin/replace.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 73 insertions(+), 1 deletion(-) diff --git a/builtin/replace.c b/builtin/replace.c index 1bb491d3c4..74593596c6 100644 --- a/builtin/replace.c +++ b/builtin/replace.c @@ -17,6 +17,7 @@ static const char * const git_replace_usage[] = { N_("git replace [-f] "), N_("git replace [-f] --edit "), + N_("git replace [-f] --graft [...]"), N_("git replace -d ..."), N_("git replace [--format=] [-l []]"), NULL @@ -294,6 +295,66 @@ static int edit_and_replace(const char *object_ref, int force) return replace_object_sha1(object_ref, old, "replacement", new, force); } +static void replace_parents(struct strbuf *buf, int argc, const char **argv) +{ + struct strbuf new_parents = STRBUF_INIT; + const char *parent_start, *parent_end; + int i; + + /* find existing parents */ + parent_start = buf->buf; + parent_start += 46; /* "tree " + "hex sha1" + "\n" */ + parent_end = parent_start; + + while (starts_with(parent_end, "parent ")) + parent_end += 48; /* "parent " + "hex sha1" + "\n" */ + + /* prepare new parents */ + for (i = 0; i < argc; i++) { + unsigned char sha1[20]; + if (get_sha1(argv[i], sha1) < 0) + die(_("Not a valid object name: '%s'"), argv[i]); + lookup_commit_or_die(sha1, argv[i]); + strbuf_addf(&new_parents, "parent %s\n", sha1_to_hex(sha1)); + } + + /* replace existing parents with new ones */ + strbuf_splice(buf, parent_start - buf->buf, parent_end - parent_start, + new_parents.buf, new_parents.len); + + strbuf_release(&new_parents); +} + +static int create_graft(int argc, const char **argv, int force) +{ + unsigned char old[20], new[20]; + const char *old_ref = argv[0]; + struct commit *commit; + struct strbuf buf = STRBUF_INIT; + const char *buffer; + unsigned long size; + + if (get_sha1(old_ref, old) < 0) + die(_("Not a valid object name: '%s'"), old_ref); + commit = lookup_commit_or_die(old, old_ref); + + buffer = get_commit_buffer(commit, &size); + strbuf_add(&buf, buffer, size); + unuse_commit_buffer(commit, buffer); + + replace_parents(&buf, argc - 1, &argv[1]); + + if (write_sha1_file(buf.buf, buf.len, commit_type, new)) + die(_("could not write replacement commit for: '%s'"), old_ref); + + strbuf_release(&buf); + + if (!hashcmp(old, new)) + return error("new commit is the same as the old one: '%s'", sha1_to_hex(old)); + + return replace_object_sha1(old_ref, old, "replacement", new, force); +} + int cmd_replace(int argc, const char **argv, const char *prefix) { int force = 0; @@ -303,12 +364,14 @@ int cmd_replace(int argc, const char **argv, const char *prefix) MODE_LIST, MODE_DELETE, MODE_EDIT, + MODE_GRAFT, MODE_REPLACE } cmdmode = MODE_UNSPECIFIED; struct option options[] = { OPT_CMDMODE('l', "list", &cmdmode, N_("list replace refs"), MODE_LIST), OPT_CMDMODE('d', "delete", &cmdmode, N_("delete replace refs"), MODE_DELETE), OPT_CMDMODE('e', "edit", &cmdmode, N_("edit existing object"), MODE_EDIT), + OPT_CMDMODE('g', "graft", &cmdmode, N_("change a commit's parents"), MODE_GRAFT), OPT_BOOL('f', "force", &force, N_("replace the ref if it exists")), OPT_STRING(0, "format", &format, N_("format"), N_("use this format")), OPT_END() @@ -325,7 +388,10 @@ int cmd_replace(int argc, const char **argv, const char *prefix) usage_msg_opt("--format cannot be used when not listing", git_replace_usage, options); - if (force && cmdmode != MODE_REPLACE && cmdmode != MODE_EDIT) + if (force && + cmdmode != MODE_REPLACE && + cmdmode != MODE_EDIT && + cmdmode != MODE_GRAFT) usage_msg_opt("-f only makes sense when writing a replacement", git_replace_usage, options); @@ -348,6 +414,12 @@ int cmd_replace(int argc, const char **argv, const char *prefix) git_replace_usage, options); return edit_and_replace(argv[0], force); + case MODE_GRAFT: + if (argc < 1) + usage_msg_opt("-g needs at least one argument", + git_replace_usage, options); + return create_graft(argc, argv, force); + case MODE_LIST: if (argc > 1) usage_msg_opt("only one pattern can be given with -l",