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#include <stdlib.h>
#include "cache.h"
#include "commit.h"
#include "refs.h"
static const char show_branch_usage[] =
"git-show-branch [--all] [--heads] [--tags] [--more=count | --list | --independent | --merge-base ] [<refs>...]";
#define UNINTERESTING 01
#define REV_SHIFT 2
#define MAX_REVS 29 /* should not exceed bits_per_int - REV_SHIFT */
static struct commit *interesting(struct commit_list *list)
{
while (list) {
struct commit *commit = list->item;
list = list->next;
if (commit->object.flags & UNINTERESTING)
continue;
return commit;
}
return NULL;
}
static struct commit *pop_one_commit(struct commit_list **list_p)
{
struct commit *commit;
struct commit_list *list;
list = *list_p;
commit = list->item;
*list_p = list->next;
free(list);
return commit;
}
struct commit_name {
const char *head_name; /* which head's ancestor? */
int generation; /* how many parents away from head_name */
};
/* Name the commit as nth generation ancestor of head_name;
* we count only the first-parent relationship for naming purposes.
*/
static void name_commit(struct commit *commit, const char *head_name, int nth)
{
struct commit_name *name;
if (!commit->object.util)
commit->object.util = xmalloc(sizeof(struct commit_name));
name = commit->object.util;
name->head_name = head_name;
name->generation = nth;
}
/* Parent is the first parent of the commit. We may name it
* as (n+1)th generation ancestor of the same head_name as
* commit is nth generation ancestore of, if that generation
* number is better than the name it already has.
*/
static void name_parent(struct commit *commit, struct commit *parent)
{
struct commit_name *commit_name = commit->object.util;
struct commit_name *parent_name = parent->object.util;
if (!commit_name)
return;
if (!parent_name ||
commit_name->generation + 1 < parent_name->generation)
name_commit(parent, commit_name->head_name,
commit_name->generation + 1);
}
static int name_first_parent_chain(struct commit *c)
{
int i = 0;
while (c) {
struct commit *p;
if (!c->object.util)
break;
if (!c->parents)
break;
p = c->parents->item;
if (!p->object.util) {
name_parent(c, p);
i++;
}
c = p;
}
return i;
}
static void name_commits(struct commit_list *list,
struct commit **rev,
char **ref_name,
int num_rev)
{
struct commit_list *cl;
struct commit *c;
int i;
/* First give names to the given heads */
for (cl = list; cl; cl = cl->next) {
c = cl->item;
if (c->object.util)
continue;
for (i = 0; i < num_rev; i++) {
if (rev[i] == c) {
name_commit(c, ref_name[i], 0);
break;
}
}
}
/* Then commits on the first parent ancestry chain */
do {
i = 0;
for (cl = list; cl; cl = cl->next) {
i += name_first_parent_chain(cl->item);
}
} while (i);
/* Finally, any unnamed commits */
do {
i = 0;
for (cl = list; cl; cl = cl->next) {
struct commit_list *parents;
struct commit_name *n;
int nth;
c = cl->item;
if (!c->object.util)
continue;
n = c->object.util;
parents = c->parents;
nth = 0;
while (parents) {
struct commit *p = parents->item;
char newname[1000];
parents = parents->next;
nth++;
if (p->object.util)
continue;
switch (n->generation) {
case 0:
sprintf(newname, "%s^%d",
n->head_name, nth);
break;
case 1:
sprintf(newname, "%s^^%d",
n->head_name, nth);
break;
default:
sprintf(newname, "%s~%d^%d",
n->head_name, n->generation,
nth);
}
name_commit(p, strdup(newname), 0);
i++;
name_first_parent_chain(p);
}
}
} while (i);
}
static int mark_seen(struct commit *commit, struct commit_list **seen_p)
{
if (!commit->object.flags) {
insert_by_date(commit, seen_p);
return 1;
}
return 0;
}
static void join_revs(struct commit_list **list_p,
struct commit_list **seen_p,
int num_rev, int extra)
{
int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
while (*list_p) {
struct commit_list *parents;
struct commit *commit = pop_one_commit(list_p);
int flags = commit->object.flags & all_mask;
int still_interesting = !!interesting(*list_p);
if (!still_interesting && extra < 0)
break;
mark_seen(commit, seen_p);
if ((flags & all_revs) == all_revs)
flags |= UNINTERESTING;
parents = commit->parents;
while (parents) {
struct commit *p = parents->item;
int this_flag = p->object.flags;
parents = parents->next;
if ((this_flag & flags) == flags)
continue;
parse_commit(p);
if (mark_seen(p, seen_p) && !still_interesting)
extra--;
p->object.flags |= flags;
insert_by_date(p, list_p);
}
}
}
static void show_one_commit(struct commit *commit)
{
char pretty[128], *cp;
struct commit_name *name = commit->object.util;
if (commit->object.parsed)
pretty_print_commit(CMIT_FMT_ONELINE, commit->buffer, ~0,
pretty, sizeof(pretty));
else
strcpy(pretty, "(unavailable)");
if (!strncmp(pretty, "[PATCH] ", 8))
cp = pretty + 8;
else
cp = pretty;
if (name && name->head_name) {
printf("[%s", name->head_name);
if (name->generation)
printf("~%d", name->generation);
printf("] ");
}
puts(cp);
}
static char *ref_name[MAX_REVS + 1];
static int ref_name_cnt;
static int compare_ref_name(const void *a_, const void *b_)
{
const char * const*a = a_, * const*b = b_;
return strcmp(*a, *b);
}
static void sort_ref_range(int bottom, int top)
{
qsort(ref_name + bottom, top - bottom, sizeof(ref_name[0]),
compare_ref_name);
}
static int append_ref(const char *refname, const unsigned char *sha1)
{
struct commit *commit = lookup_commit_reference_gently(sha1, 1);
if (!commit)
return 0;
if (MAX_REVS <= ref_name_cnt) {
fprintf(stderr, "warning: ignoring %s; "
"cannot handle more than %d refs",
refname, MAX_REVS);
return 0;
}
ref_name[ref_name_cnt++] = strdup(refname);
ref_name[ref_name_cnt] = NULL;
return 0;
}
static int append_head_ref(const char *refname, const unsigned char *sha1)
{
if (strncmp(refname, "refs/heads/", 11))
return 0;
return append_ref(refname + 11, sha1);
}
static int append_tag_ref(const char *refname, const unsigned char *sha1)
{
if (strncmp(refname, "refs/tags/", 10))
return 0;
return append_ref(refname + 5, sha1);
}
static void snarf_refs(int head, int tag)
{
if (head) {
int orig_cnt = ref_name_cnt;
for_each_ref(append_head_ref);
sort_ref_range(orig_cnt, ref_name_cnt);
}
if (tag) {
int orig_cnt = ref_name_cnt;
for_each_ref(append_tag_ref);
sort_ref_range(orig_cnt, ref_name_cnt);
}
}
static int rev_is_head(char *head_path, int headlen,
char *name,
unsigned char *head_sha1, unsigned char *sha1)
{
int namelen;
if ((!head_path[0]) || memcmp(head_sha1, sha1, 20))
return 0;
namelen = strlen(name);
if ((headlen < namelen) ||
memcmp(head_path + headlen - namelen, name, namelen))
return 0;
if (headlen == namelen ||
head_path[headlen - namelen - 1] == '/')
return 1;
return 0;
}
static int show_merge_base(struct commit_list *seen, int num_rev)
{
int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
int exit_status = 1;
while (seen) {
struct commit *commit = pop_one_commit(&seen);
int flags = commit->object.flags & all_mask;
if (!(flags & UNINTERESTING) &&
((flags & all_revs) == all_revs)) {
puts(sha1_to_hex(commit->object.sha1));
exit_status = 0;
commit->object.flags |= UNINTERESTING;
}
}
return exit_status;
}
static int show_independent(struct commit **rev,
int num_rev,
char **ref_name,
unsigned int *rev_mask)
{
int i;
for (i = 0; i < num_rev; i++) {
struct commit *commit = rev[i];
unsigned int flag = rev_mask[i];
if (commit->object.flags == flag)
puts(sha1_to_hex(commit->object.sha1));
commit->object.flags |= UNINTERESTING;
}
return 0;
}
int main(int ac, char **av)
{
struct commit *rev[MAX_REVS], *commit;
struct commit_list *list = NULL, *seen = NULL;
unsigned int rev_mask[MAX_REVS];
int num_rev, i, extra = 0;
int all_heads = 0, all_tags = 0;
int all_mask, all_revs, shown_merge_point;
char head_path[128];
const char *head_path_p;
int head_path_len;
unsigned char head_sha1[20];
int merge_base = 0;
int independent = 0;
char **label;
setup_git_directory();
while (1 < ac && av[1][0] == '-') {
char *arg = av[1];
if (!strcmp(arg, "--all"))
all_heads = all_tags = 1;
else if (!strcmp(arg, "--heads"))
all_heads = 1;
else if (!strcmp(arg, "--tags"))
all_tags = 1;
else if (!strcmp(arg, "--more"))
extra = 1;
else if (!strcmp(arg, "--list"))
extra = -1;
else if (!strncmp(arg, "--more=", 7))
extra = atoi(arg + 7);
else if (!strcmp(arg, "--merge-base"))
merge_base = 1;
else if (!strcmp(arg, "--independent"))
independent = 1;
else
usage(show_branch_usage);
ac--; av++;
}
ac--; av++;
/* Only one of these is allowed */
if (1 < independent + merge_base + (extra != 0))
usage(show_branch_usage);
if (all_heads + all_tags)
snarf_refs(all_heads, all_tags);
while (0 < ac) {
unsigned char revkey[20];
if (get_sha1(*av, revkey))
die("bad sha1 reference %s", *av);
append_ref(*av, revkey);
ac--; av++;
}
/* If still no revs, then add heads */
if (!ref_name_cnt)
snarf_refs(1, 0);
for (num_rev = 0; ref_name[num_rev]; num_rev++) {
unsigned char revkey[20];
unsigned int flag = 1u << (num_rev + REV_SHIFT);
if (MAX_REVS <= num_rev)
die("cannot handle more than %d revs.", MAX_REVS);
if (get_sha1(ref_name[num_rev], revkey))
usage(show_branch_usage);
commit = lookup_commit_reference(revkey);
if (!commit)
die("cannot find commit %s (%s)",
ref_name[num_rev], revkey);
parse_commit(commit);
mark_seen(commit, &seen);
/* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
* and so on. REV_SHIFT bits from bit 0 are used for
* internal bookkeeping.
*/
commit->object.flags |= flag;
if (commit->object.flags == flag)
insert_by_date(commit, &list);
rev[num_rev] = commit;
}
for (i = 0; i < num_rev; i++)
rev_mask[i] = rev[i]->object.flags;
if (0 <= extra)
join_revs(&list, &seen, num_rev, extra);
head_path_p = resolve_ref(git_path("HEAD"), head_sha1, 1);
if (head_path_p) {
head_path_len = strlen(head_path_p);
memcpy(head_path, head_path_p, head_path_len + 1);
}
else {
head_path_len = 0;
head_path[0] = 0;
}
if (merge_base)
return show_merge_base(seen, num_rev);
if (independent)
return show_independent(rev, num_rev, ref_name, rev_mask);
/* Show list; --more=-1 means list-only */
if (1 < num_rev || extra < 0) {
for (i = 0; i < num_rev; i++) {
int j;
int is_head = rev_is_head(head_path,
head_path_len,
ref_name[i],
head_sha1,
rev[i]->object.sha1);
if (extra < 0)
printf("%c [%s] ",
is_head ? '*' : ' ', ref_name[i]);
else {
for (j = 0; j < i; j++)
putchar(' ');
printf("%c [%s] ",
is_head ? '*' : '!', ref_name[i]);
}
show_one_commit(rev[i]);
}
if (0 <= extra) {
for (i = 0; i < num_rev; i++)
putchar('-');
putchar('\n');
}
}
if (extra < 0)
exit(0);
/* Sort topologically */
sort_in_topological_order(&seen);
/* Give names to commits */
name_commits(seen, rev, ref_name, num_rev);
all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
shown_merge_point = 0;
while (seen) {
struct commit *commit = pop_one_commit(&seen);
int this_flag = commit->object.flags;
int is_merge_point = (this_flag & all_revs) == all_revs;
static char *obvious[] = { "" };
if (is_merge_point)
shown_merge_point = 1;
if (1 < num_rev) {
for (i = 0; i < num_rev; i++)
putchar((this_flag & (1u << (i + REV_SHIFT)))
? '+' : ' ');
putchar(' ');
}
show_one_commit(commit);
if (num_rev == 1)
label = obvious;
if (shown_merge_point && is_merge_point)
if (--extra < 0)
break;
}
return 0;
}
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