Hi,
I sent a patch to rewrite branch in C and make it a builtin a couple of months ago. Junio had a few comments about the patch that I now finally had the time to address. One of the problems was that merge-base didn't clean up its state, which has now been fixed. Here's the updated version.
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
commit 8153d336ad9643507922932a2ac2277073c66432 Author: Kristian Høgsberg <krh@redhat.com> Date: Sun Aug 20 17:04:14 2006 -0400
Rewrite branch in C and make it a builtin.
Show changes to 5 files +174 −131
Makefile, builtin-branch.c, builtin.h, git-branch.sh, git.c
diff --git a/Makefile b/Makefile index 23cd8a0..adf043e 100644 --- a/Makefile +++ b/Makefile @@ -149,7 +149,7 @@ SPARSE_FLAGS = -D__BIG_ENDIAN__ -D__powe ### --- END CONFIGURATION SECTION --- SCRIPT_SH = \ - git-bisect.sh git-branch.sh git-checkout.sh \ + git-bisect.sh git-checkout.sh \ git-cherry.sh git-clean.sh git-clone.sh git-commit.sh \ git-fetch.sh \ git-ls-remote.sh \ @@ -253,6 +253,7 @@ LIB_OBJS = \ BUILTIN_OBJS = \ builtin-add.o \ builtin-apply.o \ + builtin-branch.o \ builtin-cat-file.o \ builtin-checkout-index.o \ builtin-check-ref-format.o \ diff --git a/builtin-branch.c b/builtin-branch.c new file mode 100644 index 0000000..25c6313 --- /dev/null +++ b/builtin-branch.c @@ -0,0 +1,170 @@ +/* + * Builtin "git branch" + * + * Copyright (c) 2006 Kristian Høgsberg <krh@redhat.com> + * Based on git-branch.sh by Junio C Hamano. + */ + +#include "cache.h" +#include "refs.h" +#include "commit.h" +#include "builtin.h" + +static const char builtin_branch_usage[] = + "git-branch [(-d | -D) <branchname>] | [[-f] <branchname> [<start-point>]] | -r"; + + +static int remote_only = 0; +static const char *head; +static unsigned char head_sha1[20]; + +static int in_merge_bases(const unsigned char *sha1, + struct commit *rev1, + struct commit *rev2) +{ + struct commit_list *bases, *b; + + bases = get_merge_bases(rev1, rev2, 1); + for (b = bases; b != NULL; b = b->next) { + if (!hashcmp(sha1, b->item->object.sha1)) { + free_commit_list(bases); + return 1; + } + } + + free_commit_list(bases); + return 0; +} + +static void delete_branches(int argc, const char **argv, int force) +{ + struct commit *rev1, *rev2; + unsigned char sha1[20]; + const char *p, *name; + int i; + + for (i = 0; i < argc; i++) { + if (!strcmp(head, argv[i])) + die("Cannot delete the branch you are currently on."); + + name = git_path("refs/heads/%s", argv[i]); + p = resolve_ref(name, sha1, 1); + if (p == NULL) + die("Branch '%s' not found.", argv[i]); + + rev1 = lookup_commit_reference(sha1); + rev2 = lookup_commit_reference(head_sha1); + if (!rev1 || !rev2) + die("Couldn't look up commit objects."); + + /* This checks wether the merge bases of branch and + * HEAD contains branch -- which means that the HEAD + * contains everything in both. + */ + + if (!force && + !in_merge_bases(sha1, rev1, rev2)) { + fprintf(stderr, + "The branch '%s' is not a strict subset of your current HEAD.\n" + "If you are sure you want to delete it, run 'git branch -D %s'.\n", + argv[i], argv[i]); + exit(1); + } + + unlink(name); + printf("Deleted branch %s.\n", argv[i]); + } +} + +static int show_reference(const char *refname, const unsigned char *sha1) +{ + int is_head = !strcmp(refname, head); + + printf("%c %s\n", (is_head ? '*' : ' '), refname); + + return 0; +} + +static void create_branch (const char *name, const char *start, int force) +{ + struct ref_lock *lock; + unsigned char sha1[20]; + char ref[PATH_MAX]; + + snprintf(ref, sizeof ref, "refs/heads/%s", name); + if (check_ref_format(ref + 5)) + die("'%s' is not a valid branch name.", name); + + if (resolve_ref(ref, sha1, 1)) { + if (!force) + die("A branch named '%s' already exists.", name); + else if (!strcmp(head, name)) + die("Cannot force update the current branch."); + } + + if (get_sha1(start, sha1)) + die("Not a valid branch point: '%s'", start); + + lock = lock_any_ref_for_update(ref, NULL, 0); + if (!lock) + die("Failed to lock ref for update: %s.", strerror(errno)); + if (write_ref_sha1(lock, sha1, NULL) < 0) + die("Failed to write ref: %s.", strerror(errno)); +} + +int cmd_branch(int argc, const char **argv, const char *prefix) +{ + int delete = 0, force_delete = 0, force_create = 0; + int i, prefix_length; + const char *p; + + git_config(git_default_config); + + for (i = 1; i < argc; i++) { + const char *arg = argv[i]; + + if (arg[0] != '-') + break; + if (!strcmp(arg, "--")) { + i++; + break; + } + if (!strcmp(arg, "-d")) { + delete = 1; + continue; + } + if (!strcmp(arg, "-D")) { + delete = 1; + force_delete = 1; + continue; + } + if (!strcmp(arg, "-f")) { + force_create = 1; + continue; + } + if (!strcmp(arg, "-r")) { + remote_only = 1; + continue; + } + die(builtin_branch_usage); + } + + prefix_length = strlen(git_path("refs/heads/")); + p = resolve_ref(git_path("HEAD"), head_sha1, 0); + if (!p) + die("Failed to resolve HEAD as a valid ref"); + head = strdup(p + prefix_length); + + if (delete) + delete_branches(argc - i, argv + i, force_delete); + else if (i == argc && remote_only) + for_each_remote_ref(show_reference); + else if (i == argc) + for_each_branch_ref(show_reference); + else if (argc - i == 1) + create_branch (argv[i], head, force_create); + else + create_branch (argv[i], argv[i + 1], force_create); + + return 0; +} diff --git a/builtin.h b/builtin.h index ade58c4..eb28986 100644 --- a/builtin.h +++ b/builtin.h @@ -15,6 +15,7 @@ extern int write_tree(unsigned char *sha extern int cmd_add(int argc, const char **argv, const char *prefix); extern int cmd_apply(int argc, const char **argv, const char *prefix); +extern int cmd_branch(int argc, const char **argv, const char *prefix); extern int cmd_cat_file(int argc, const char **argv, const char *prefix); extern int cmd_checkout_index(int argc, const char **argv, const char *prefix); extern int cmd_check_ref_format(int argc, const char **argv, const char *prefix); diff --git a/git-branch.sh b/git-branch.sh deleted file mode 100755 index e0501ec..0000000 --- a/git-branch.sh +++ /dev/null @@ -1,130 +0,0 @@ -#!/bin/sh - -USAGE='[-l] [(-d | -D) <branchname>] | [[-f] <branchname> [<start-point>]] | -r' -LONG_USAGE='If no arguments, show available branches and mark current branch with a star. -If one argument, create a new branch <branchname> based off of current HEAD. -If two arguments, create a new branch <branchname> based off of <start-point>.' - -SUBDIRECTORY_OK='Yes' -. git-sh-setup - -headref=$(git-symbolic-ref HEAD | sed -e 's|^refs/heads/||') - -delete_branch () { - option="$1" - shift - for branch_name - do - case ",$headref," in - ",$branch_name,") - die "Cannot delete the branch you are on." ;; - ,,) - die "What branch are you on anyway?" ;; - esac - branch=$(cat "$GIT_DIR/refs/heads/$branch_name") && - branch=$(git-rev-parse --verify "$branch^0") || - die "Seriously, what branch are you talking about?" - case "$option" in - -D) - ;; - *) - mbs=$(git-merge-base -a "$branch" HEAD | tr '\012' ' ') - case " $mbs " in - *' '$branch' '*) - # the merge base of branch and HEAD contains branch -- - # which means that the HEAD contains everything in both. - ;; - *) - echo >&2 "The branch '$branch_name' is not a strict subset of your current HEAD. -If you are sure you want to delete it, run 'git branch -D $branch_name'." - exit 1 - ;; - esac - ;; - esac - rm -f "$GIT_DIR/logs/refs/heads/$branch_name" - rm -f "$GIT_DIR/refs/heads/$branch_name" - echo "Deleted branch $branch_name." - done - exit 0 -} - -ls_remote_branches () { - git-rev-parse --symbolic --all | - sed -ne 's|^refs/\(remotes/\)|\1|p' | - sort -} - -force= -create_log= -while case "$#,$1" in 0,*) break ;; *,-*) ;; *) break ;; esac -do - case "$1" in - -d | -D) - delete_branch "$@" - exit - ;; - -r) - ls_remote_branches - exit - ;; - -f) - force="$1" - ;; - -l) - create_log="yes" - ;; - --) - shift - break - ;; - -*) - usage - ;; - esac - shift -done - -case "$#" in -0) - git-rev-parse --symbolic --branches | - sort | - while read ref - do - if test "$headref" = "$ref" - then - pfx='*' - else - pfx=' ' - fi - echo "$pfx $ref" - done - exit 0 ;; -1) - head=HEAD ;; -2) - head="$2^0" ;; -esac -branchname="$1" - -rev=$(git-rev-parse --verify "$head") || exit - -git-check-ref-format "heads/$branchname" || - die "we do not like '$branchname' as a branch name." - -if [ -e "$GIT_DIR/refs/heads/$branchname" ] -then - if test '' = "$force" - then - die "$branchname already exists." - elif test "$branchname" = "$headref" - then - die "cannot force-update the current branch." - fi -fi -if test "$create_log" = 'yes' -then - mkdir -p $(dirname "$GIT_DIR/logs/refs/heads/$branchname") - touch "$GIT_DIR/logs/refs/heads/$branchname" -fi -git update-ref -m "branch: Created from $head" "refs/heads/$branchname" $rev diff --git a/git.c b/git.c index 930998b..5738cb4 100644 --- a/git.c +++ b/git.c @@ -226,6 +226,7 @@ static void handle_internal_command(int } commands[] = { { "add", cmd_add, RUN_SETUP }, { "apply", cmd_apply }, + { "branch", cmd_branch, RUN_SETUP }, { "cat-file", cmd_cat_file, RUN_SETUP }, { "checkout-index", cmd_checkout_index, RUN_SETUP }, { "check-ref-format", cmd_check_ref_format },
