[PATCH 1/3] git-branch: add --track and --no-track options
- From
Paolo Bonzini <bonzini@gnu.org>
- Date
- Mar 5, 2007, 08:57 UTC
- Message-ID
- <esgm1m$33f$1@sea.gmane.org>
In order to track and build on top of a branch 'topic' you track from your upstream repository, you often would end up doing this sequence:
git checkout -b mytopic origin/topic git config --add branch.mytopic.remote origin git config --add branch.mytopic.merge refs/heads/topic
This would first fork your own 'mytopic' branch from the 'topic' branch you track from the 'origin' repository; then it would set up two configuration variables so that 'git pull' without parameters does the right thing while you are on your own 'mytopic' branch.
This commit adds a --track option to git-branch, so that "git branch --track topic origin/topic" performs the latter two actions when creating your 'topic' branch. By setting configuration variable 'remote.REMOTENAME.trackintolocalbranches' to true, you do not have to pass the --track option explicitly (the configuration variable is off by default, and there is a --no-track option to countermand it even if the variable is set).
Signed-off-by: Paolo Bonzini <bonzini@gnu.org> --- Documentation/git-branch.txt | 9 ++- builtin-branch.c | 126 ++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 127 insertions(+), 8 deletions(-)
diff --git a/Documentation/git-branch.txt b/Documentation/git-branch.txt index 3ea3b80..bd65b98 100644 --- a/Documentation/git-branch.txt +++ b/Documentation/git-branch.txt @@ -10,7 +10,7 @@ SYNOPSIS [verse] 'git-branch' [--color | --no-color] [-r | -a] [-v [--abbrev=<length> | --no-abbrev]] -'git-branch' [-l] [-f] <branchname> [<start-point>] +'git-branch' [--track | --no-track] [-l] [-f] <branchname> [<start-point>] 'git-branch' (-m | -M) [<oldbranch>] <newbranch> 'git-branch' (-d | -D) [-r] <branchname>... @@ -26,6 +26,13 @@ It will start out with a head equal to the one given as <start-point>. If no <start-point> is given, the branch will be created with a head equal to that of the currently checked out branch. +When a local branch is started off a remote branch, git can setup the +branch so that gitlink:git-pull[1] will appropriately merge from that +remote branch. If this behavior is desired, it is possible to make it +the default using the `trackintolocalbranches` option of the +corresponding remote. Otherwise, it can be chosen per-branch using +the `--track` and `--no-track` options. + With a '-m' or '-M' option, <oldbranch> will be renamed to <newbranch>. If <oldbranch> had a corresponding reflog, it is renamed to match <newbranch>, and a reflog entry is created to remember the branch diff --git a/builtin-branch.c b/builtin-branch.c index d371849..f39759b 100644 --- a/builtin-branch.c +++ b/builtin-branch.c @@ -12,7 +12,7 @@ #include "builtin.h" static const char builtin_branch_usage[] = - "git-branch [-r] (-d | -D) <branchname> | [-l] [-f] <branchname> [<start-point>] | (-m | -M) [<oldbranch>] <newbranch> | [--color | --no-color] [-r | -a] [-v [--abbrev=<length> | --no-abbrev]]"; + "git-branch [-r] (-d | -D) <branchname> | [--track | --no-track] [-l] [-f] <branchname> [<start-point>] | (-m | -M) [<oldbranch>] <newbranch> | [--color | --no-color] [-r | -a] [-v [--abbrev=<length> | --no-abbrev]]"; #define REF_UNKNOWN_TYPE 0x00 #define REF_LOCAL_BRANCH 0x01 @@ -308,14 +308,105 @@ static void print_ref_list(int kinds, int detached, int verbose, int abbrev) free_ref_list(&ref_list); } + +static int config_track; +static char *config_repo; +static const char *start_ref; +static int start_len; +static int remote_len; + +static void get_remote_branch_name(const char* value) +{ + int len_first = -1, len_second = -1; + if (*value == '+') + value++; + + /* Try an exact match first. */ + sscanf(value, "refs/%*[^:]:%n", &len_first); + if (len_first != -1 + && !strcmp(value + len_first, start_ref)) { + /* Truncate the value before the colon. */ + asprintf(&config_repo, "%.*s", len_first - 1, value); + return; + } + + /* Try with a wildcard match now. */ + sscanf(value, "refs/%*[^/]/*:%nrefs/remotes/%*[^/]/*%n", + &len_first, &len_second); + if (len_first != -1 && len_second != -1 + && (len_second - 2) - len_first == remote_len + 13 + && !strncmp(value + len_first, start_ref, remote_len + 13)) { + /* Replace the star with the remote branch name. */ + asprintf(&config_repo, "%.*s%s", + len_first - 3, value, + start_ref + remote_len + 13); + } +} + +static int get_remote_config(const char* key, const char* value) +{ + if (!prefixcmp(key, "remote.") && + !strncmp(key + 7, start_ref + 13, remote_len)) { + if (config_track == -1 + && !strcmp(key + 7 + remote_len, ".trackintolocalbranches")) + config_track = git_config_bool(key, value); + + else if (!strcmp(key + 7 + remote_len, ".fetch")) + get_remote_branch_name(value); + } + return 0; +} + +static void register_pull(const char *name, const char *real_ref, int track) +{ + char key[1024], value[1024]; + const char *remote_name = real_ref + 13; + const char *slash = strchr(remote_name, '/'); + + if (!slash) + return; + + start_ref = real_ref; + start_len = strlen(real_ref); + remote_len = slash - remote_name; + config_track = track; + git_config(get_remote_config); + + /* Change to != 0 to enable this feature by default. */ + if (config_track == 1 && config_repo) { + if (snprintf(key, sizeof(key), "branch.%s.remote", name) + > sizeof(key)) { + die("what a long branch name you have!"); + goto out; + } + if (snprintf(value, sizeof(value), "%.*s", remote_len, remote_name) + > sizeof(value)) { + die("what a long branch name you have!"); + goto out; + } + + git_config_set(key, value); + + snprintf(key, sizeof(key), "branch.%s.merge", name); + git_config_set(key, config_repo); + + printf("Branch %s set up to track remote branch %s.\n", + name, real_ref); + } + + out: + if (config_repo) + free(config_repo); +} + static void create_branch(const char *name, const char *start_name, unsigned char *start_sha1, - int force, int reflog) + int force, int reflog, int track) { struct ref_lock *lock; struct commit *commit; unsigned char sha1[20]; - char ref[PATH_MAX], msg[PATH_MAX + 20]; + char *real_ref = NULL, ref[PATH_MAX], msg[PATH_MAX + 20]; int forcing = 0; snprintf(ref, sizeof ref, "refs/heads/%s", name); @@ -333,7 +424,9 @@ static void create_branch(const char *name, const char *start_name, if (start_sha1) /* detached HEAD */ hashcpy(sha1, start_sha1); - else if (get_sha1(start_name, sha1)) + else if (dwim_ref(start_name, strlen(start_name), sha1, &real_ref) > 1) + die("Ambiguous object name: '%s'.", start_name); + else if (real_ref == NULL) die("Not a valid object name: '%s'.", start_name); if ((commit = lookup_commit_reference(sha1)) == NULL) @@ -354,8 +447,17 @@ static void create_branch(const char *name, const char *start_name, snprintf(msg, sizeof msg, "branch: Created from %s", start_name); + /* When branching off a remote branch, set up so that git-pull + automatically merges from there. So far, this is only done for + branches registered using git-remote. */ + if (!prefixcmp(real_ref, "refs/remotes/")) + register_pull(name, real_ref, track); + if (write_ref_sha1(lock, sha1, msg) < 0) die("Failed to write ref: %s.", strerror(errno)); + + if (real_ref) + free(real_ref); } static void rename_branch(const char *oldname, const char *newname, int force) @@ -397,7 +499,7 @@ int cmd_branch(int argc, const char **argv, const char *prefix) int delete = 0, force_delete = 0, force_create = 0; int rename = 0, force_rename = 0; int verbose = 0, abbrev = DEFAULT_ABBREV, detached = 0; - int reflog = 0; + int reflog = 0, track = -1; int kinds = REF_LOCAL_BRANCH; int i; @@ -412,6 +514,14 @@ int cmd_branch(int argc, const char **argv, const char *prefix) i++; break; } + if (!strcmp(arg, "--track")) { + track = 1; + continue; + } + if (!strcmp(arg, "--no-track")) { + track = 0; + continue; + } if (!strcmp(arg, "-d")) { delete = 1; continue; @@ -498,9 +608,11 @@ int cmd_branch(int argc, const char **argv, const char *prefix) else if (rename && (i == argc - 2)) rename_branch(argv[i], argv[i + 1], force_rename); else if (i == argc - 1) - create_branch(argv[i], head, head_sha1, force_create, reflog); + create_branch(argv[i], head, head_sha1, force_create, reflog, + track); else if (i == argc - 2) - create_branch(argv[i], argv[i+1], NULL, force_create, reflog); + create_branch(argv[i], argv[i+1], NULL, force_create, reflog, + track); else usage(builtin_branch_usage);