From 4228e8bc989c6cac1c47faece720faa06531281f Mon Sep 17 00:00:00 2001 From: Christian Couder Date: Sat, 19 Jul 2014 17:01:08 +0200 Subject: 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(-) (limited to 'builtin/replace.c') 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", -- cgit v1.3 From 0b05ab6f1bfa045f460ad5c40d87ef8c2965bf56 Mon Sep 17 00:00:00 2001 From: Christian Couder Date: Sat, 19 Jul 2014 17:01:12 +0200 Subject: replace: remove signature when using --graft It could be misleading to keep a signature in a replacement commit, so let's remove it. Note that there should probably be a way to sign the replacement commit created when using --graft, but this can be dealt with in another commit or patch series. Signed-off-by: Christian Couder Signed-off-by: Junio C Hamano --- builtin/replace.c | 5 +++++ commit.c | 34 ++++++++++++++++++++++++++++++++++ commit.h | 2 ++ 3 files changed, 41 insertions(+) (limited to 'builtin/replace.c') diff --git a/builtin/replace.c b/builtin/replace.c index 74593596c6..52f73ce557 100644 --- a/builtin/replace.c +++ b/builtin/replace.c @@ -344,6 +344,11 @@ static int create_graft(int argc, const char **argv, int force) replace_parents(&buf, argc - 1, &argv[1]); + if (remove_signature(&buf)) { + warning(_("the original commit '%s' has a gpg signature."), old_ref); + warning(_("the signature will be removed in the replacement commit!")); + } + if (write_sha1_file(buf.buf, buf.len, commit_type, new)) die(_("could not write replacement commit for: '%s'"), old_ref); diff --git a/commit.c b/commit.c index 94b1af9392..ca26c69452 100644 --- a/commit.c +++ b/commit.c @@ -1178,6 +1178,40 @@ int parse_signed_commit(const struct commit *commit, return saw_signature; } +int remove_signature(struct strbuf *buf) +{ + const char *line = buf->buf; + const char *tail = buf->buf + buf->len; + int in_signature = 0; + const char *sig_start = NULL; + const char *sig_end = NULL; + + while (line < tail) { + const char *next = memchr(line, '\n', tail - line); + next = next ? next + 1 : tail; + + if (in_signature && line[0] == ' ') + sig_end = next; + else if (starts_with(line, gpg_sig_header) && + line[gpg_sig_header_len] == ' ') { + sig_start = line; + sig_end = next; + in_signature = 1; + } else { + if (*line == '\n') + /* dump the whole remainder of the buffer */ + next = tail; + in_signature = 0; + } + line = next; + } + + if (sig_start) + strbuf_remove(buf, sig_start - buf->buf, sig_end - sig_start); + + return sig_start != NULL; +} + static void handle_signed_tag(struct commit *parent, struct commit_extra_header ***tail) { struct merge_remote_desc *desc; diff --git a/commit.h b/commit.h index b695aa4a5b..c81ba8530c 100644 --- a/commit.h +++ b/commit.h @@ -332,6 +332,8 @@ struct commit *get_merge_parent(const char *name); extern int parse_signed_commit(const struct commit *commit, struct strbuf *message, struct strbuf *signature); +extern int remove_signature(struct strbuf *buf); + extern void print_commit_list(struct commit_list *list, const char *format_cur, const char *format_last); -- cgit v1.3 From 25a05a8cae263ca55e75d31336d09c8d9bc90be3 Mon Sep 17 00:00:00 2001 From: Christian Couder Date: Sat, 19 Jul 2014 17:01:14 +0200 Subject: replace: check mergetags when using --graft When using --graft, with a mergetag in the original commit, we should check that the commit pointed to by the mergetag is still a parent of then new commit we create, otherwise the mergetag could be misleading. If the commit pointed to by the mergetag is no more a parent of the new commit, we could remove the mergetag, but in this case there is a good chance that the title or other elements of the commit might also be misleading. So let's just error out and suggest to use --edit instead on the commit. Signed-off-by: Christian Couder Signed-off-by: Junio C Hamano --- builtin/replace.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) (limited to 'builtin/replace.c') diff --git a/builtin/replace.c b/builtin/replace.c index 52f73ce557..d29026fe21 100644 --- a/builtin/replace.c +++ b/builtin/replace.c @@ -13,6 +13,7 @@ #include "refs.h" #include "parse-options.h" #include "run-command.h" +#include "tag.h" static const char * const git_replace_usage[] = { N_("git replace [-f] "), @@ -325,6 +326,50 @@ static void replace_parents(struct strbuf *buf, int argc, const char **argv) strbuf_release(&new_parents); } +struct check_mergetag_data { + int argc; + const char **argv; +}; + +static void check_one_mergetag(struct commit *commit, + struct commit_extra_header *extra, + void *data) +{ + struct check_mergetag_data *mergetag_data = (struct check_mergetag_data *)data; + const char *ref = mergetag_data->argv[0]; + unsigned char tag_sha1[20]; + struct tag *tag; + int i; + + hash_sha1_file(extra->value, extra->len, typename(OBJ_TAG), tag_sha1); + tag = lookup_tag(tag_sha1); + if (!tag) + die(_("bad mergetag in commit '%s'"), ref); + if (parse_tag_buffer(tag, extra->value, extra->len)) + die(_("malformed mergetag in commit '%s'"), ref); + + /* iterate over new parents */ + for (i = 1; i < mergetag_data->argc; i++) { + unsigned char sha1[20]; + if (get_sha1(mergetag_data->argv[i], sha1) < 0) + die(_("Not a valid object name: '%s'"), mergetag_data->argv[i]); + if (!hashcmp(tag->tagged->sha1, sha1)) + return; /* found */ + } + + die(_("original commit '%s' contains mergetag '%s' that is discarded; " + "use --edit instead of --graft"), ref, sha1_to_hex(tag_sha1)); +} + +static void check_mergetags(struct commit *commit, int argc, const char **argv) +{ + struct check_mergetag_data mergetag_data; + + mergetag_data.argc = argc; + mergetag_data.argv = argv; + for_each_mergetag(check_one_mergetag, commit, &mergetag_data); +} + static int create_graft(int argc, const char **argv, int force) { unsigned char old[20], new[20]; @@ -349,6 +394,8 @@ static int create_graft(int argc, const char **argv, int force) warning(_("the signature will be removed in the replacement commit!")); } + check_mergetags(commit, argc, argv); + if (write_sha1_file(buf.buf, buf.len, commit_type, new)) die(_("could not write replacement commit for: '%s'"), old_ref); -- cgit v1.3