{"thread":{"id":"1606","subject":"[PATCH] Add 'git show-branch'.","startedAt":"2005-08-21T09:51:10Z","lastAt":"2005-08-21T09:51:10Z","messageCount":1,"participants":["Junio C Hamano"],"isPatch":true,"patchVersion":1,"patchTotal":null},"messages":[{"id":"7606","messageId":"7vfyt3ipo1.fsf@assigned-by-dhcp.cox.net","threadId":"1606","inReplyTo":null,"subject":"[PATCH] Add 'git show-branch'.","fromName":"Junio C Hamano","fromEmail":"junkio@cox.net","sentAt":"2005-08-21T09:51:10Z","receivedAt":"2005-08-21T09:51:10Z","isPatch":true,"sender":{"key":"gitster@pobox.com","avatar":"https://avatars.githubusercontent.com/u/54884?v=4"},"body":"The 'git show-branches' command turns out to be reasonably useful,\nbut painfully slow.  So rewrite it in C, using ideas from merge-base\nwhile enhancing it a bit more.\n\n - Unlike show-branches, it can take --heads (show me all my\n   heads), --tags (show me all my tags), or --all (both).\n\n - It can take --more=<number> to show beyond the merge-base.\n\n - It shows the short name for each commit in the extended SHA1\n   syntax.\n\n - It can find merge-base for more than two heads.\n\nExamples:\n\n    $ git show-branch --more=6 HEAD\n\n    is almost the same as \"git log --pretty=oneline --max-count=6\".\n\n    $ git show-branch --merge-base master mhf misc\n\n    finds the merge base of the three given heads.\n\n    $ git show-branch --all --more=10\n\n    is poor-man's gitk, showing all the tags and heads, and\n    going back 10 commits beyond the merge base of those refs.\n\nSigned-off-by: Junio C Hamano <junkio@cox.net>\n\n---\n\n Makefile      |    2 \n commit.c      |   21 +++-\n commit.h      |    2 \n show-branch.c |  325 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n 4 files changed, 343 insertions(+), 7 deletions(-)\n create mode 100644 show-branch.c\n\n660c5d6332b541e2186c93374eef637e30894c62\ndiff --git a/Makefile b/Makefile\n--- a/Makefile\n+++ b/Makefile\n@@ -85,7 +85,7 @@ PROG=   git-update-cache git-diff-files \n \tgit-diff-stages git-rev-parse git-patch-id git-pack-objects \\\n \tgit-unpack-objects git-verify-pack git-receive-pack git-send-pack \\\n \tgit-prune-packed git-fetch-pack git-upload-pack git-clone-pack \\\n-\tgit-show-index git-daemon git-var git-peek-remote \\\n+\tgit-show-index git-daemon git-var git-peek-remote git-show-branch \\\n \tgit-update-server-info git-show-rev-cache git-build-rev-cache\n \n ifndef NO_CURL\ndiff --git a/commit.c b/commit.c\n--- a/commit.c\n+++ b/commit.c\n@@ -38,23 +38,32 @@ enum cmit_fmt get_commit_format(const ch\n \tdie(\"invalid --pretty format\");\n }\n \n-static struct commit *check_commit(struct object *obj, const unsigned char *sha1)\n+static struct commit *check_commit(struct object *obj,\n+\t\t\t\t   const unsigned char *sha1,\n+\t\t\t\t   int quiet)\n {\n \tif (obj->type != commit_type) {\n-\t\terror(\"Object %s is a %s, not a commit\", \n-\t\t      sha1_to_hex(sha1), obj->type);\n+\t\tif (!quiet)\n+\t\t\terror(\"Object %s is a %s, not a commit\",\n+\t\t\t      sha1_to_hex(sha1), obj->type);\n \t\treturn NULL;\n \t}\n \treturn (struct commit *) obj;\n }\n \n-struct commit *lookup_commit_reference(const unsigned char *sha1)\n+struct commit *lookup_commit_reference_gently(const unsigned char *sha1,\n+\t\t\t\t\t      int quiet)\n {\n \tstruct object *obj = deref_tag(parse_object(sha1));\n \n \tif (!obj)\n \t\treturn NULL;\n-\treturn check_commit(obj, sha1);\n+\treturn check_commit(obj, sha1, quiet);\n+}\n+\n+struct commit *lookup_commit_reference(const unsigned char *sha1)\n+{\n+\treturn lookup_commit_reference_gently(sha1, 0);\n }\n \n struct commit *lookup_commit(const unsigned char *sha1)\n@@ -69,7 +78,7 @@ struct commit *lookup_commit(const unsig\n \t}\n \tif (!obj->type)\n \t\tobj->type = commit_type;\n-\treturn check_commit(obj, sha1);\n+\treturn check_commit(obj, sha1, 0);\n }\n \n static unsigned long parse_commit_date(const char *buf)\ndiff --git a/commit.h b/commit.h\n--- a/commit.h\n+++ b/commit.h\n@@ -21,6 +21,8 @@ extern const char *commit_type;\n \n struct commit *lookup_commit(const unsigned char *sha1);\n struct commit *lookup_commit_reference(const unsigned char *sha1);\n+struct commit *lookup_commit_reference_gently(const unsigned char *sha1,\n+\t\t\t\t\t      int quiet);\n \n int parse_commit_buffer(struct commit *item, void *buffer, unsigned long size);\n \ndiff --git a/show-branch.c b/show-branch.c\nnew file mode 100644\n--- /dev/null\n+++ b/show-branch.c\n@@ -0,0 +1,325 @@\n+#include <stdlib.h>\n+#include \"cache.h\"\n+#include \"commit.h\"\n+#include \"refs.h\"\n+\n+static const char show_branch_usage[] =\n+\"git-show-branch [--all] [--heads] [--tags] [--more=count] [<refs>...]\";\n+\n+#define UNINTERESTING\t01\n+\n+#define REV_SHIFT\t 2\n+#define MAX_REVS\t29 /* should not exceed bits_per_int - REV_SHIFT */\n+\n+static struct commit *interesting(struct commit_list *list)\n+{\n+\twhile (list) {\n+\t\tstruct commit *commit = list->item;\n+\t\tlist = list->next;\n+\t\tif (commit->object.flags & UNINTERESTING)\n+\t\t\tcontinue;\n+\t\treturn commit;\n+\t}\n+\treturn NULL;\n+}\n+\n+static struct commit *pop_one_commit(struct commit_list **list_p)\n+{\n+\tstruct commit *commit;\n+\tstruct commit_list *list;\n+\tlist = *list_p;\n+\tcommit = list->item;\n+\t*list_p = list->next;\n+\tfree(list);\n+\treturn commit;\n+}\n+\n+struct commit_name {\n+\tint head_rev;\t/* which head's ancestor? */\n+\tint generation;\t/* how many parents away from head_rev */\n+};\n+\n+/* Name the commit as nth generation ancestor of head_rev;\n+ * we count only the first-parent relationship for naming purposes.\n+ */\n+static void name_commit(struct commit *commit, int head_rev, int nth)\n+{\n+\tstruct commit_name *name;\n+\tif (!commit->object.util)\n+\t\tcommit->object.util = xmalloc(sizeof(struct commit_name));\n+\tname = commit->object.util;\n+\tname->head_rev = head_rev;\n+\tname->generation = nth;\n+}\n+\n+/* Parent is the first parent of the commit.  We may name it\n+ * as (n+1)th generation ancestor of the same head_rev as\n+ * commit is nth generation ancestore of, if that generation\n+ * number is better than the name it already has.\n+ */\n+static void name_parent(struct commit *commit, struct commit *parent)\n+{\n+\tstruct commit_name *commit_name = commit->object.util;\n+\tstruct commit_name *parent_name = parent->object.util;\n+\tif (!commit_name)\n+\t\treturn;\n+\tif (!parent_name ||\n+\t    commit_name->generation + 1 < parent_name->generation)\n+\t\tname_commit(parent, commit_name->head_rev,\n+\t\t\t    commit_name->generation + 1);\n+}\n+\n+static int mark_seen(struct commit *commit, struct commit_list **seen_p)\n+{\n+\tif (!commit->object.flags) {\n+\t\tinsert_by_date(commit, seen_p);\n+\t\treturn 1;\n+\t}\n+\treturn 0;\n+}\n+\n+static void join_revs(struct commit_list **list_p,\n+\t\t      struct commit_list **seen_p,\n+\t\t      int num_rev, int extra)\n+{\n+\tint all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);\n+\tint all_revs = all_mask & ~((1u << REV_SHIFT) - 1);\n+\n+\twhile (*list_p) {\n+\t\tstruct commit_list *parents;\n+\t\tstruct commit *commit = pop_one_commit(list_p);\n+\t\tint flags = commit->object.flags & all_mask;\n+\t\tint nth_parent = 0;\n+\t\tint still_interesting = !!interesting(*list_p);\n+\n+\t\tif (!still_interesting && extra < 0)\n+\t\t\tbreak;\n+\n+\t\tmark_seen(commit, seen_p);\n+\t\tif ((flags & all_revs) == all_revs)\n+\t\t\tflags |= UNINTERESTING;\n+\t\tparents = commit->parents;\n+\n+\t\twhile (parents) {\n+\t\t\tstruct commit *p = parents->item;\n+\t\t\tint this_flag = p->object.flags;\n+\t\t\tparents = parents->next;\n+\t\t\tnth_parent++;\n+\t\t\tif (nth_parent == 1)\n+\t\t\t\tname_parent(commit, p);\n+\n+\t\t\tif ((this_flag & flags) == flags)\n+\t\t\t\tcontinue;\n+\t\t\tparse_commit(p);\n+\t\t\tif (mark_seen(p, seen_p) && !still_interesting)\n+\t\t\t\textra--;\n+\t\t\tp->object.flags |= flags;\n+\t\t\tinsert_by_date(p, list_p);\n+\t\t}\n+\t}\n+}\n+\n+static void show_one_commit(struct commit *commit, char **head_name)\n+{\n+\tchar pretty[128], *cp;\n+\tstruct commit_name *name = commit->object.util;\n+\tpretty_print_commit(CMIT_FMT_ONELINE, commit->buffer, ~0,\n+\t\t\t    pretty, sizeof(pretty));\n+\tif (!strncmp(pretty, \"[PATCH] \", 8))\n+\t\tcp = pretty + 8;\n+\telse\n+\t\tcp = pretty;\n+\tif (name) {\n+\t\tprintf(\"[%s\", head_name[name->head_rev]);\n+\t\tif (name->generation)\n+\t\t\tprintf(\":%d\", name->generation);\n+\t\tprintf(\"] \");\n+\t}\n+\tputs(cp);\n+}\n+\n+static char *ref_name[MAX_REVS + 1];\n+static int ref_name_cnt;\n+\n+static int append_ref(const char *refname, const unsigned char *sha1)\n+{\n+\tstruct commit *commit = lookup_commit_reference_gently(sha1, 1);\n+\tif (!commit)\n+\t\treturn 0;\n+\tif (MAX_REVS < ref_name_cnt) {\n+\t\tfprintf(stderr, \"warning: ignoring %s; \"\n+\t\t\t\"cannot handle more than %d refs\",\n+\t\t\trefname, MAX_REVS);\n+\t\treturn 0;\n+\t}\n+\tref_name[ref_name_cnt++] = strdup(refname);\n+\tref_name[ref_name_cnt] = NULL;\n+\treturn 0;\n+}\n+\n+static int append_head_ref(const char *refname, const unsigned char *sha1)\n+{\n+\tif (strncmp(refname, \"refs/heads/\", 11))\n+\t\treturn 0;\n+\treturn append_ref(refname + 5, sha1);\n+}\n+\n+static int append_tag_ref(const char *refname, const unsigned char *sha1)\n+{\n+\tif (strncmp(refname, \"refs/tags/\", 10))\n+\t\treturn 0;\n+\treturn append_ref(refname + 5, sha1);\n+}\n+\n+static void snarf_refs(int head, int tag)\n+{\n+\tif (head)\n+\t\tfor_each_ref(append_head_ref);\n+\tif (tag)\n+\t\tfor_each_ref(append_tag_ref);\n+}\n+\n+static int rev_is_head(char *head_path, int headlen,\n+\t\t       char *name,\n+\t\t       unsigned char *head_sha1, unsigned char *sha1)\n+{\n+\tint namelen;\n+\tif ((!head_path[0]) || memcmp(head_sha1, sha1, 20))\n+\t\treturn 0;\n+\tnamelen = strlen(name);\n+\tif ((headlen < namelen) ||\n+\t    memcmp(head_path + headlen - namelen, name, namelen))\n+\t\treturn 0;\n+\tif (headlen == namelen ||\n+\t    head_path[headlen - namelen - 1] == '/')\n+\t\treturn 1;\n+\treturn 0;\n+}\n+\n+static int show_merge_base(struct commit_list *seen, int num_rev)\n+{\n+\tint all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);\n+\tint all_revs = all_mask & ~((1u << REV_SHIFT) - 1);\n+\n+\twhile (seen) {\n+\t\tstruct commit *commit = pop_one_commit(&seen);\n+\t\tint flags = commit->object.flags & all_mask;\n+\t\tif (!(flags & UNINTERESTING) &&\n+\t\t    ((flags & all_revs) == all_revs)) {\n+\t\t\tputs(sha1_to_hex(commit->object.sha1));\n+\t\t\treturn 0;\n+\t\t}\n+\t}\n+\treturn 1;\n+}\n+\n+int main(int ac, char **av)\n+{\n+\tstruct commit *rev[MAX_REVS], *commit;\n+\tstruct commit_list *list = NULL, *seen = NULL;\n+\tint num_rev, i, extra = 0;\n+\tint all_heads = 0, all_tags = 0;\n+\tchar head_path[128];\n+\tint head_path_len;\n+\tunsigned char head_sha1[20];\n+\tint merge_base = 0;\n+\n+\twhile (1 < ac && av[1][0] == '-') {\n+\t\tchar *arg = av[1];\n+\t\tif (!strcmp(arg, \"--all\"))\n+\t\t\tall_heads = all_tags = 1;\n+\t\telse if (!strcmp(arg, \"--heads\"))\n+\t\t\tall_heads = 1;\n+\t\telse if (!strcmp(arg, \"--tags\"))\n+\t\t\tall_tags = 1;\n+\t\telse if (!strcmp(arg, \"--more\"))\n+\t\t\textra = 1;\n+\t\telse if (!strncmp(arg, \"--more=\", 7)) {\n+\t\t\textra = atoi(arg + 7);\n+\t\t\tif (extra < 0)\n+\t\t\t\tusage(show_branch_usage);\n+\t\t}\n+\t\telse if (!strcmp(arg, \"--merge-base\"))\n+\t\t\tmerge_base = 1;\n+\t\telse\n+\t\t\tusage(show_branch_usage);\n+\t\tac--; av++;\n+\t}\n+\tac--; av++;\n+\n+\tif (all_heads + all_tags)\n+\t\tsnarf_refs(all_heads, all_tags);\n+\n+\twhile (0 < ac) {\n+\t\tunsigned char revkey[20];\n+\t\tif (get_sha1(*av, revkey))\n+\t\t\tdie(\"bad sha1 reference %s\", *av);\n+\t\tappend_ref(*av, revkey);\n+\t\tac--; av++;\n+\t}\n+\n+\t/* If still no revs, then add heads */\n+\tif (!ref_name_cnt)\n+\t\tsnarf_refs(1, 0);\n+\n+\tfor (num_rev = 0; ref_name[num_rev]; num_rev++) {\n+\t\tunsigned char revkey[20];\n+\n+\t\tif (MAX_REVS <= num_rev)\n+\t\t\tdie(\"cannot handle more than %d revs.\", MAX_REVS);\n+\t\tif (get_sha1(ref_name[num_rev], revkey))\n+\t\t\tusage(show_branch_usage);\n+\t\tcommit = lookup_commit_reference(revkey);\n+\t\tif (!commit)\n+\t\t\tdie(\"cannot find commit %s (%s)\",\n+\t\t\t    ref_name[num_rev], revkey);\n+\t\tparse_commit(commit);\n+\t\tif (!commit->object.util)\n+\t\t\tname_commit(commit, num_rev, 0);\n+\t\tmark_seen(commit, &seen);\n+\n+\t\t/* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,\n+\t\t * and so on.  REV_SHIFT bits from bit 0 are used for\n+\t\t * internal bookkeeping.\n+\t\t */\n+\t\tcommit->object.flags |= 1u << (num_rev + REV_SHIFT);\n+\t\tinsert_by_date(commit, &list);\n+\t\trev[num_rev] = commit;\n+\t}\n+\tjoin_revs(&list, &seen, num_rev, extra);\n+\n+\thead_path_len = readlink(\".git/HEAD\", head_path, sizeof(head_path)-1);\n+\tif ((head_path_len < 0) || get_sha1(\"HEAD\", head_sha1))\n+\t\thead_path[0] = 0;\n+\telse\n+\t\thead_path[head_path_len] = 0;\n+\n+\tif (merge_base)\n+\t\treturn show_merge_base(seen, num_rev);\n+\n+\tif (1 < num_rev)\n+\t\tfor (i = 0; i < num_rev; i++) {\n+\t\t\tint j;\n+\t\t\tint is_head = rev_is_head(head_path,\n+\t\t\t\t\t\t  head_path_len,\n+\t\t\t\t\t\t  ref_name[i],\n+\t\t\t\t\t\t  head_sha1,\n+\t\t\t\t\t\t  rev[i]->object.sha1);\n+\t\t\tfor (j = 0; j < i; j++)\n+\t\t\t\tputchar(' ');\n+\t\t\tprintf(\"%c \", is_head ? '*' : '!');\n+\t\t\tshow_one_commit(rev[i], ref_name);\n+\t\t}\n+\twhile (seen) {\n+\t\tstruct commit *commit = pop_one_commit(&seen);\n+\t\tint this_flag = commit->object.flags;\n+\t\tif ((this_flag & UNINTERESTING) && (--extra < 0))\n+\t\t\tbreak;\n+\t\tfor (i = 0; i < num_rev; i++)\n+\t\t\tputchar((this_flag & (1u << (i + REV_SHIFT)))\n+\t\t\t\t? '+' : ' ');\n+\t\tputchar(' ');\n+\t\tshow_one_commit(commit, ref_name);\n+\t}\n+\treturn 0;\n+}\n"}]}