git/commit.c

1584 строки
38 KiB
C

#include "cache.h"
#include "tag.h"
#include "commit.h"
#include "pkt-line.h"
#include "utf8.h"
#include "diff.h"
#include "revision.h"
#include "notes.h"
#include "gpg-interface.h"
#include "mergesort.h"
#include "commit-slab.h"
#include "prio-queue.h"
static struct commit_extra_header *read_commit_extra_header_lines(const char *buf, size_t len, const char **);
int save_commit_buffer = 1;
const char *commit_type = "commit";
static int commit_count;
static struct commit *check_commit(struct object *obj,
const unsigned char *sha1,
int quiet)
{
if (obj->type != OBJ_COMMIT) {
if (!quiet)
error("Object %s is a %s, not a commit",
sha1_to_hex(sha1), typename(obj->type));
return NULL;
}
return (struct commit *) obj;
}
struct commit *lookup_commit_reference_gently(const unsigned char *sha1,
int quiet)
{
struct object *obj = deref_tag(parse_object(sha1), NULL, 0);
if (!obj)
return NULL;
return check_commit(obj, sha1, quiet);
}
struct commit *lookup_commit_reference(const unsigned char *sha1)
{
return lookup_commit_reference_gently(sha1, 0);
}
struct commit *lookup_commit_or_die(const unsigned char *sha1, const char *ref_name)
{
struct commit *c = lookup_commit_reference(sha1);
if (!c)
die(_("could not parse %s"), ref_name);
if (hashcmp(sha1, c->object.sha1)) {
warning(_("%s %s is not a commit!"),
ref_name, sha1_to_hex(sha1));
}
return c;
}
struct commit *lookup_commit(const unsigned char *sha1)
{
struct object *obj = lookup_object(sha1);
if (!obj) {
struct commit *c = alloc_commit_node();
c->index = commit_count++;
return create_object(sha1, OBJ_COMMIT, c);
}
if (!obj->type)
obj->type = OBJ_COMMIT;
return check_commit(obj, sha1, 0);
}
struct commit *lookup_commit_reference_by_name(const char *name)
{
unsigned char sha1[20];
struct commit *commit;
if (get_sha1_committish(name, sha1))
return NULL;
commit = lookup_commit_reference(sha1);
if (!commit || parse_commit(commit))
return NULL;
return commit;
}
static unsigned long parse_commit_date(const char *buf, const char *tail)
{
const char *dateptr;
if (buf + 6 >= tail)
return 0;
if (memcmp(buf, "author", 6))
return 0;
while (buf < tail && *buf++ != '\n')
/* nada */;
if (buf + 9 >= tail)
return 0;
if (memcmp(buf, "committer", 9))
return 0;
while (buf < tail && *buf++ != '>')
/* nada */;
if (buf >= tail)
return 0;
dateptr = buf;
while (buf < tail && *buf++ != '\n')
/* nada */;
if (buf >= tail)
return 0;
/* dateptr < buf && buf[-1] == '\n', so strtoul will stop at buf-1 */
return strtoul(dateptr, NULL, 10);
}
static struct commit_graft **commit_graft;
static int commit_graft_alloc, commit_graft_nr;
static int commit_graft_pos(const unsigned char *sha1)
{
int lo, hi;
lo = 0;
hi = commit_graft_nr;
while (lo < hi) {
int mi = (lo + hi) / 2;
struct commit_graft *graft = commit_graft[mi];
int cmp = hashcmp(sha1, graft->sha1);
if (!cmp)
return mi;
if (cmp < 0)
hi = mi;
else
lo = mi + 1;
}
return -lo - 1;
}
int register_commit_graft(struct commit_graft *graft, int ignore_dups)
{
int pos = commit_graft_pos(graft->sha1);
if (0 <= pos) {
if (ignore_dups)
free(graft);
else {
free(commit_graft[pos]);
commit_graft[pos] = graft;
}
return 1;
}
pos = -pos - 1;
if (commit_graft_alloc <= ++commit_graft_nr) {
commit_graft_alloc = alloc_nr(commit_graft_alloc);
commit_graft = xrealloc(commit_graft,
sizeof(*commit_graft) *
commit_graft_alloc);
}
if (pos < commit_graft_nr)
memmove(commit_graft + pos + 1,
commit_graft + pos,
(commit_graft_nr - pos - 1) *
sizeof(*commit_graft));
commit_graft[pos] = graft;
return 0;
}
struct commit_graft *read_graft_line(char *buf, int len)
{
/* The format is just "Commit Parent1 Parent2 ...\n" */
int i;
struct commit_graft *graft = NULL;
while (len && isspace(buf[len-1]))
buf[--len] = '\0';
if (buf[0] == '#' || buf[0] == '\0')
return NULL;
if ((len + 1) % 41)
goto bad_graft_data;
i = (len + 1) / 41 - 1;
graft = xmalloc(sizeof(*graft) + 20 * i);
graft->nr_parent = i;
if (get_sha1_hex(buf, graft->sha1))
goto bad_graft_data;
for (i = 40; i < len; i += 41) {
if (buf[i] != ' ')
goto bad_graft_data;
if (get_sha1_hex(buf + i + 1, graft->parent[i/41]))
goto bad_graft_data;
}
return graft;
bad_graft_data:
error("bad graft data: %s", buf);
free(graft);
return NULL;
}
static int read_graft_file(const char *graft_file)
{
FILE *fp = fopen(graft_file, "r");
char buf[1024];
if (!fp)
return -1;
while (fgets(buf, sizeof(buf), fp)) {
/* The format is just "Commit Parent1 Parent2 ...\n" */
int len = strlen(buf);
struct commit_graft *graft = read_graft_line(buf, len);
if (!graft)
continue;
if (register_commit_graft(graft, 1))
error("duplicate graft data: %s", buf);
}
fclose(fp);
return 0;
}
static void prepare_commit_graft(void)
{
static int commit_graft_prepared;
char *graft_file;
if (commit_graft_prepared)
return;
graft_file = get_graft_file();
read_graft_file(graft_file);
/* make sure shallows are read */
is_repository_shallow();
commit_graft_prepared = 1;
}
struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
{
int pos;
prepare_commit_graft();
pos = commit_graft_pos(sha1);
if (pos < 0)
return NULL;
return commit_graft[pos];
}
int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data)
{
int i, ret;
for (i = ret = 0; i < commit_graft_nr && !ret; i++)
ret = fn(commit_graft[i], cb_data);
return ret;
}
int unregister_shallow(const unsigned char *sha1)
{
int pos = commit_graft_pos(sha1);
if (pos < 0)
return -1;
if (pos + 1 < commit_graft_nr)
memmove(commit_graft + pos, commit_graft + pos + 1,
sizeof(struct commit_graft *)
* (commit_graft_nr - pos - 1));
commit_graft_nr--;
return 0;
}
int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size)
{
const char *tail = buffer;
const char *bufptr = buffer;
unsigned char parent[20];
struct commit_list **pptr;
struct commit_graft *graft;
if (item->object.parsed)
return 0;
item->object.parsed = 1;
tail += size;
if (tail <= bufptr + 46 || memcmp(bufptr, "tree ", 5) || bufptr[45] != '\n')
return error("bogus commit object %s", sha1_to_hex(item->object.sha1));
if (get_sha1_hex(bufptr + 5, parent) < 0)
return error("bad tree pointer in commit %s",
sha1_to_hex(item->object.sha1));
item->tree = lookup_tree(parent);
bufptr += 46; /* "tree " + "hex sha1" + "\n" */
pptr = &item->parents;
graft = lookup_commit_graft(item->object.sha1);
while (bufptr + 48 < tail && !memcmp(bufptr, "parent ", 7)) {
struct commit *new_parent;
if (tail <= bufptr + 48 ||
get_sha1_hex(bufptr + 7, parent) ||
bufptr[47] != '\n')
return error("bad parents in commit %s", sha1_to_hex(item->object.sha1));
bufptr += 48;
/*
* The clone is shallow if nr_parent < 0, and we must
* not traverse its real parents even when we unhide them.
*/
if (graft && (graft->nr_parent < 0 || grafts_replace_parents))
continue;
new_parent = lookup_commit(parent);
if (new_parent)
pptr = &commit_list_insert(new_parent, pptr)->next;
}
if (graft) {
int i;
struct commit *new_parent;
for (i = 0; i < graft->nr_parent; i++) {
new_parent = lookup_commit(graft->parent[i]);
if (!new_parent)
continue;
pptr = &commit_list_insert(new_parent, pptr)->next;
}
}
item->date = parse_commit_date(bufptr, tail);
return 0;
}
int parse_commit(struct commit *item)
{
enum object_type type;
void *buffer;
unsigned long size;
int ret;
if (!item)
return -1;
if (item->object.parsed)
return 0;
buffer = read_sha1_file(item->object.sha1, &type, &size);
if (!buffer)
return error("Could not read %s",
sha1_to_hex(item->object.sha1));
if (type != OBJ_COMMIT) {
free(buffer);
return error("Object %s not a commit",
sha1_to_hex(item->object.sha1));
}
ret = parse_commit_buffer(item, buffer, size);
if (save_commit_buffer && !ret) {
item->buffer = buffer;
return 0;
}
free(buffer);
return ret;
}
int find_commit_subject(const char *commit_buffer, const char **subject)
{
const char *eol;
const char *p = commit_buffer;
while (*p && (*p != '\n' || p[1] != '\n'))
p++;
if (*p) {
p += 2;
for (eol = p; *eol && *eol != '\n'; eol++)
; /* do nothing */
} else
eol = p;
*subject = p;
return eol - p;
}
struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
{
struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
new_list->item = item;
new_list->next = *list_p;
*list_p = new_list;
return new_list;
}
unsigned commit_list_count(const struct commit_list *l)
{
unsigned c = 0;
for (; l; l = l->next )
c++;
return c;
}
void free_commit_list(struct commit_list *list)
{
while (list) {
struct commit_list *temp = list;
list = temp->next;
free(temp);
}
}
struct commit_list * commit_list_insert_by_date(struct commit *item, struct commit_list **list)
{
struct commit_list **pp = list;
struct commit_list *p;
while ((p = *pp) != NULL) {
if (p->item->date < item->date) {
break;
}
pp = &p->next;
}
return commit_list_insert(item, pp);
}
static int commit_list_compare_by_date(const void *a, const void *b)
{
unsigned long a_date = ((const struct commit_list *)a)->item->date;
unsigned long b_date = ((const struct commit_list *)b)->item->date;
if (a_date < b_date)
return 1;
if (a_date > b_date)
return -1;
return 0;
}
static void *commit_list_get_next(const void *a)
{
return ((const struct commit_list *)a)->next;
}
static void commit_list_set_next(void *a, void *next)
{
((struct commit_list *)a)->next = next;
}
void commit_list_sort_by_date(struct commit_list **list)
{
*list = llist_mergesort(*list, commit_list_get_next, commit_list_set_next,
commit_list_compare_by_date);
}
struct commit *pop_most_recent_commit(struct commit_list **list,
unsigned int mark)
{
struct commit *ret = (*list)->item;
struct commit_list *parents = ret->parents;
struct commit_list *old = *list;
*list = (*list)->next;
free(old);
while (parents) {
struct commit *commit = parents->item;
if (!parse_commit(commit) && !(commit->object.flags & mark)) {
commit->object.flags |= mark;
commit_list_insert_by_date(commit, list);
}
parents = parents->next;
}
return ret;
}
static void clear_commit_marks_1(struct commit_list **plist,
struct commit *commit, unsigned int mark)
{
while (commit) {
struct commit_list *parents;
if (!(mark & commit->object.flags))
return;
commit->object.flags &= ~mark;
parents = commit->parents;
if (!parents)
return;
while ((parents = parents->next))
commit_list_insert(parents->item, plist);
commit = commit->parents->item;
}
}
void clear_commit_marks_many(int nr, struct commit **commit, unsigned int mark)
{
struct commit_list *list = NULL;
while (nr--) {
commit_list_insert(*commit, &list);
commit++;
}
while (list)
clear_commit_marks_1(&list, pop_commit(&list), mark);
}
void clear_commit_marks(struct commit *commit, unsigned int mark)
{
clear_commit_marks_many(1, &commit, mark);
}
void clear_commit_marks_for_object_array(struct object_array *a, unsigned mark)
{
struct object *object;
struct commit *commit;
unsigned int i;
for (i = 0; i < a->nr; i++) {
object = a->objects[i].item;
commit = lookup_commit_reference_gently(object->sha1, 1);
if (commit)
clear_commit_marks(commit, mark);
}
}
struct commit *pop_commit(struct commit_list **stack)
{
struct commit_list *top = *stack;
struct commit *item = top ? top->item : NULL;
if (top) {
*stack = top->next;
free(top);
}
return item;
}
/*
* Topological sort support
*/
/* count number of children that have not been emitted */
define_commit_slab(indegree_slab, int);
/* record author-date for each commit object */
define_commit_slab(author_date_slab, unsigned long);
static void record_author_date(struct author_date_slab *author_date,
struct commit *commit)
{
const char *buf, *line_end;
char *buffer = NULL;
struct ident_split ident;
char *date_end;
unsigned long date;
if (!commit->buffer) {
unsigned long size;
enum object_type type;
buffer = read_sha1_file(commit->object.sha1, &type, &size);
if (!buffer)
return;
}
for (buf = commit->buffer ? commit->buffer : buffer;
buf;
buf = line_end + 1) {
line_end = strchrnul(buf, '\n');
if (prefixcmp(buf, "author ")) {
if (!line_end[0] || line_end[1] == '\n')
return; /* end of header */
continue;
}
if (split_ident_line(&ident,
buf + strlen("author "),
line_end - (buf + strlen("author "))) ||
!ident.date_begin || !ident.date_end)
goto fail_exit; /* malformed "author" line */
break;
}
date = strtoul(ident.date_begin, &date_end, 10);
if (date_end != ident.date_end)
goto fail_exit; /* malformed date */
*(author_date_slab_at(author_date, commit)) = date;
fail_exit:
free(buffer);
}
static int compare_commits_by_author_date(const void *a_, const void *b_,
void *cb_data)
{
const struct commit *a = a_, *b = b_;
struct author_date_slab *author_date = cb_data;
unsigned long a_date = *(author_date_slab_at(author_date, a));
unsigned long b_date = *(author_date_slab_at(author_date, b));
/* newer commits with larger date first */
if (a_date < b_date)
return 1;
else if (a_date > b_date)
return -1;
return 0;
}
int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused)
{
const struct commit *a = a_, *b = b_;
/* newer commits with larger date first */
if (a->date < b->date)
return 1;
else if (a->date > b->date)
return -1;
return 0;
}
/*
* Performs an in-place topological sort on the list supplied.
*/
void sort_in_topological_order(struct commit_list **list, enum rev_sort_order sort_order)
{
struct commit_list *next, *orig = *list;
struct commit_list **pptr;
struct indegree_slab indegree;
struct prio_queue queue;
struct commit *commit;
struct author_date_slab author_date;
if (!orig)
return;
*list = NULL;
init_indegree_slab(&indegree);
memset(&queue, '\0', sizeof(queue));
switch (sort_order) {
default: /* REV_SORT_IN_GRAPH_ORDER */
queue.compare = NULL;
break;
case REV_SORT_BY_COMMIT_DATE:
queue.compare = compare_commits_by_commit_date;
break;
case REV_SORT_BY_AUTHOR_DATE:
init_author_date_slab(&author_date);
queue.compare = compare_commits_by_author_date;
queue.cb_data = &author_date;
break;
}
/* Mark them and clear the indegree */
for (next = orig; next; next = next->next) {
struct commit *commit = next->item;
*(indegree_slab_at(&indegree, commit)) = 1;
/* also record the author dates, if needed */
if (sort_order == REV_SORT_BY_AUTHOR_DATE)
record_author_date(&author_date, commit);
}
/* update the indegree */
for (next = orig; next; next = next->next) {
struct commit_list *parents = next->item->parents;
while (parents) {
struct commit *parent = parents->item;
int *pi = indegree_slab_at(&indegree, parent);
if (*pi)
(*pi)++;
parents = parents->next;
}
}
/*
* find the tips
*
* tips are nodes not reachable from any other node in the list
*
* the tips serve as a starting set for the work queue.
*/
for (next = orig; next; next = next->next) {
struct commit *commit = next->item;
if (*(indegree_slab_at(&indegree, commit)) == 1)
prio_queue_put(&queue, commit);
}
/*
* This is unfortunate; the initial tips need to be shown
* in the order given from the revision traversal machinery.
*/
if (sort_order == REV_SORT_IN_GRAPH_ORDER)
prio_queue_reverse(&queue);
/* We no longer need the commit list */
free_commit_list(orig);
pptr = list;
*list = NULL;
while ((commit = prio_queue_get(&queue)) != NULL) {
struct commit_list *parents;
for (parents = commit->parents; parents ; parents = parents->next) {
struct commit *parent = parents->item;
int *pi = indegree_slab_at(&indegree, parent);
if (!*pi)
continue;
/*
* parents are only enqueued for emission
* when all their children have been emitted thereby
* guaranteeing topological order.
*/
if (--(*pi) == 1)
prio_queue_put(&queue, parent);
}
/*
* all children of commit have already been
* emitted. we can emit it now.
*/
*(indegree_slab_at(&indegree, commit)) = 0;
pptr = &commit_list_insert(commit, pptr)->next;
}
clear_indegree_slab(&indegree);
clear_prio_queue(&queue);
if (sort_order == REV_SORT_BY_AUTHOR_DATE)
clear_author_date_slab(&author_date);
}
/* merge-base stuff */
/* bits #0..15 in revision.h */
#define PARENT1 (1u<<16)
#define PARENT2 (1u<<17)
#define STALE (1u<<18)
#define RESULT (1u<<19)
static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
static struct commit *interesting(struct commit_list *list)
{
while (list) {
struct commit *commit = list->item;
list = list->next;
if (commit->object.flags & STALE)
continue;
return commit;
}
return NULL;
}
/* all input commits in one and twos[] must have been parsed! */
static struct commit_list *paint_down_to_common(struct commit *one, int n, struct commit **twos)
{
struct commit_list *list = NULL;
struct commit_list *result = NULL;
int i;
one->object.flags |= PARENT1;
commit_list_insert_by_date(one, &list);
if (!n)
return list;
for (i = 0; i < n; i++) {
twos[i]->object.flags |= PARENT2;
commit_list_insert_by_date(twos[i], &list);
}
while (interesting(list)) {
struct commit *commit;
struct commit_list *parents;
struct commit_list *next;
int flags;
commit = list->item;
next = list->next;
free(list);
list = next;
flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
if (flags == (PARENT1 | PARENT2)) {
if (!(commit->object.flags & RESULT)) {
commit->object.flags |= RESULT;
commit_list_insert_by_date(commit, &result);
}
/* Mark parents of a found merge stale */
flags |= STALE;
}
parents = commit->parents;
while (parents) {
struct commit *p = parents->item;
parents = parents->next;
if ((p->object.flags & flags) == flags)
continue;
if (parse_commit(p))
return NULL;
p->object.flags |= flags;
commit_list_insert_by_date(p, &list);
}
}
free_commit_list(list);
return result;
}
static struct commit_list *merge_bases_many(struct commit *one, int n, struct commit **twos)
{
struct commit_list *list = NULL;
struct commit_list *result = NULL;
int i;
for (i = 0; i < n; i++) {
if (one == twos[i])
/*
* We do not mark this even with RESULT so we do not
* have to clean it up.
*/
return commit_list_insert(one, &result);
}
if (parse_commit(one))
return NULL;
for (i = 0; i < n; i++) {
if (parse_commit(twos[i]))
return NULL;
}
list = paint_down_to_common(one, n, twos);
while (list) {
struct commit_list *next = list->next;
if (!(list->item->object.flags & STALE))
commit_list_insert_by_date(list->item, &result);
free(list);
list = next;
}
return result;
}
struct commit_list *get_octopus_merge_bases(struct commit_list *in)
{
struct commit_list *i, *j, *k, *ret = NULL;
struct commit_list **pptr = &ret;
for (i = in; i; i = i->next) {
if (!ret)
pptr = &commit_list_insert(i->item, pptr)->next;
else {
struct commit_list *new = NULL, *end = NULL;
for (j = ret; j; j = j->next) {
struct commit_list *bases;
bases = get_merge_bases(i->item, j->item, 1);
if (!new)
new = bases;
else
end->next = bases;
for (k = bases; k; k = k->next)
end = k;
}
ret = new;
}
}
return ret;
}
static int remove_redundant(struct commit **array, int cnt)
{
/*
* Some commit in the array may be an ancestor of
* another commit. Move such commit to the end of
* the array, and return the number of commits that
* are independent from each other.
*/
struct commit **work;
unsigned char *redundant;
int *filled_index;
int i, j, filled;
work = xcalloc(cnt, sizeof(*work));
redundant = xcalloc(cnt, 1);
filled_index = xmalloc(sizeof(*filled_index) * (cnt - 1));
for (i = 0; i < cnt; i++)
parse_commit(array[i]);
for (i = 0; i < cnt; i++) {
struct commit_list *common;
if (redundant[i])
continue;
for (j = filled = 0; j < cnt; j++) {
if (i == j || redundant[j])
continue;
filled_index[filled] = j;
work[filled++] = array[j];
}
common = paint_down_to_common(array[i], filled, work);
if (array[i]->object.flags & PARENT2)
redundant[i] = 1;
for (j = 0; j < filled; j++)
if (work[j]->object.flags & PARENT1)
redundant[filled_index[j]] = 1;
clear_commit_marks(array[i], all_flags);
for (j = 0; j < filled; j++)
clear_commit_marks(work[j], all_flags);
free_commit_list(common);
}
/* Now collect the result */
memcpy(work, array, sizeof(*array) * cnt);
for (i = filled = 0; i < cnt; i++)
if (!redundant[i])
array[filled++] = work[i];
for (j = filled, i = 0; i < cnt; i++)
if (redundant[i])
array[j++] = work[i];
free(work);
free(redundant);
free(filled_index);
return filled;
}
struct commit_list *get_merge_bases_many(struct commit *one,
int n,
struct commit **twos,
int cleanup)
{
struct commit_list *list;
struct commit **rslt;
struct commit_list *result;
int cnt, i;
result = merge_bases_many(one, n, twos);
for (i = 0; i < n; i++) {
if (one == twos[i])
return result;
}
if (!result || !result->next) {
if (cleanup) {
clear_commit_marks(one, all_flags);
clear_commit_marks_many(n, twos, all_flags);
}
return result;
}
/* There are more than one */
cnt = 0;
list = result;
while (list) {
list = list->next;
cnt++;
}
rslt = xcalloc(cnt, sizeof(*rslt));
for (list = result, i = 0; list; list = list->next)
rslt[i++] = list->item;
free_commit_list(result);
clear_commit_marks(one, all_flags);
clear_commit_marks_many(n, twos, all_flags);
cnt = remove_redundant(rslt, cnt);
result = NULL;
for (i = 0; i < cnt; i++)
commit_list_insert_by_date(rslt[i], &result);
free(rslt);
return result;
}
struct commit_list *get_merge_bases(struct commit *one, struct commit *two,
int cleanup)
{
return get_merge_bases_many(one, 1, &two, cleanup);
}
/*
* Is "commit" a descendant of one of the elements on the "with_commit" list?
*/
int is_descendant_of(struct commit *commit, struct commit_list *with_commit)
{
if (!with_commit)
return 1;
while (with_commit) {
struct commit *other;
other = with_commit->item;
with_commit = with_commit->next;
if (in_merge_bases(other, commit))
return 1;
}
return 0;
}
/*
* Is "commit" an ancestor of one of the "references"?
*/
int in_merge_bases_many(struct commit *commit, int nr_reference, struct commit **reference)
{
struct commit_list *bases;
int ret = 0, i;
if (parse_commit(commit))
return ret;
for (i = 0; i < nr_reference; i++)
if (parse_commit(reference[i]))
return ret;
bases = paint_down_to_common(commit, nr_reference, reference);
if (commit->object.flags & PARENT2)
ret = 1;
clear_commit_marks(commit, all_flags);
clear_commit_marks_many(nr_reference, reference, all_flags);
free_commit_list(bases);
return ret;
}
/*
* Is "commit" an ancestor of (i.e. reachable from) the "reference"?
*/
int in_merge_bases(struct commit *commit, struct commit *reference)
{
return in_merge_bases_many(commit, 1, &reference);
}
struct commit_list *reduce_heads(struct commit_list *heads)
{
struct commit_list *p;
struct commit_list *result = NULL, **tail = &result;
struct commit **array;
int num_head, i;
if (!heads)
return NULL;
/* Uniquify */
for (p = heads; p; p = p->next)
p->item->object.flags &= ~STALE;
for (p = heads, num_head = 0; p; p = p->next) {
if (p->item->object.flags & STALE)
continue;
p->item->object.flags |= STALE;
num_head++;
}
array = xcalloc(sizeof(*array), num_head);
for (p = heads, i = 0; p; p = p->next) {
if (p->item->object.flags & STALE) {
array[i++] = p->item;
p->item->object.flags &= ~STALE;
}
}
num_head = remove_redundant(array, num_head);
for (i = 0; i < num_head; i++)
tail = &commit_list_insert(array[i], tail)->next;
return result;
}
static const char gpg_sig_header[] = "gpgsig";
static const int gpg_sig_header_len = sizeof(gpg_sig_header) - 1;
static int do_sign_commit(struct strbuf *buf, const char *keyid)
{
struct strbuf sig = STRBUF_INIT;
int inspos, copypos;
/* find the end of the header */
inspos = strstr(buf->buf, "\n\n") - buf->buf + 1;
if (!keyid || !*keyid)
keyid = get_signing_key();
if (sign_buffer(buf, &sig, keyid)) {
strbuf_release(&sig);
return -1;
}
for (copypos = 0; sig.buf[copypos]; ) {
const char *bol = sig.buf + copypos;
const char *eol = strchrnul(bol, '\n');
int len = (eol - bol) + !!*eol;
if (!copypos) {
strbuf_insert(buf, inspos, gpg_sig_header, gpg_sig_header_len);
inspos += gpg_sig_header_len;
}
strbuf_insert(buf, inspos++, " ", 1);
strbuf_insert(buf, inspos, bol, len);
inspos += len;
copypos += len;
}
strbuf_release(&sig);
return 0;
}
int parse_signed_commit(const unsigned char *sha1,
struct strbuf *payload, struct strbuf *signature)
{
unsigned long size;
enum object_type type;
char *buffer = read_sha1_file(sha1, &type, &size);
int in_signature, saw_signature = -1;
char *line, *tail;
if (!buffer || type != OBJ_COMMIT)
goto cleanup;
line = buffer;
tail = buffer + size;
in_signature = 0;
saw_signature = 0;
while (line < tail) {
const char *sig = NULL;
char *next = memchr(line, '\n', tail - line);
next = next ? next + 1 : tail;
if (in_signature && line[0] == ' ')
sig = line + 1;
else if (!prefixcmp(line, gpg_sig_header) &&
line[gpg_sig_header_len] == ' ')
sig = line + gpg_sig_header_len + 1;
if (sig) {
strbuf_add(signature, sig, next - sig);
saw_signature = 1;
in_signature = 1;
} else {
if (*line == '\n')
/* dump the whole remainder of the buffer */
next = tail;
strbuf_add(payload, line, next - line);
in_signature = 0;
}
line = next;
}
cleanup:
free(buffer);
return saw_signature;
}
static void handle_signed_tag(struct commit *parent, struct commit_extra_header ***tail)
{
struct merge_remote_desc *desc;
struct commit_extra_header *mergetag;
char *buf;
unsigned long size, len;
enum object_type type;
desc = merge_remote_util(parent);
if (!desc || !desc->obj)
return;
buf = read_sha1_file(desc->obj->sha1, &type, &size);
if (!buf || type != OBJ_TAG)
goto free_return;
len = parse_signature(buf, size);
if (size == len)
goto free_return;
/*
* We could verify this signature and either omit the tag when
* it does not validate, but the integrator may not have the
* public key of the signer of the tag he is merging, while a
* later auditor may have it while auditing, so let's not run
* verify-signed-buffer here for now...
*
* if (verify_signed_buffer(buf, len, buf + len, size - len, ...))
* warn("warning: signed tag unverified.");
*/
mergetag = xcalloc(1, sizeof(*mergetag));
mergetag->key = xstrdup("mergetag");
mergetag->value = buf;
mergetag->len = size;
**tail = mergetag;
*tail = &mergetag->next;
return;
free_return:
free(buf);
}
static struct {
char result;
const char *check;
} sigcheck_gpg_status[] = {
{ 'G', "\n[GNUPG:] GOODSIG " },
{ 'B', "\n[GNUPG:] BADSIG " },
{ 'U', "\n[GNUPG:] TRUST_NEVER" },
{ 'U', "\n[GNUPG:] TRUST_UNDEFINED" },
};
static void parse_gpg_output(struct signature_check *sigc)
{
const char *buf = sigc->gpg_status;
int i;
/* Iterate over all search strings */
for (i = 0; i < ARRAY_SIZE(sigcheck_gpg_status); i++) {
const char *found, *next;
if (!prefixcmp(buf, sigcheck_gpg_status[i].check + 1)) {
/* At the very beginning of the buffer */
found = buf + strlen(sigcheck_gpg_status[i].check + 1);
} else {
found = strstr(buf, sigcheck_gpg_status[i].check);
if (!found)
continue;
found += strlen(sigcheck_gpg_status[i].check);
}
sigc->result = sigcheck_gpg_status[i].result;
/* The trust messages are not followed by key/signer information */
if (sigc->result != 'U') {
sigc->key = xmemdupz(found, 16);
found += 17;
next = strchrnul(found, '\n');
sigc->signer = xmemdupz(found, next - found);
}
}
}
void check_commit_signature(const struct commit* commit, struct signature_check *sigc)
{
struct strbuf payload = STRBUF_INIT;
struct strbuf signature = STRBUF_INIT;
struct strbuf gpg_output = STRBUF_INIT;
struct strbuf gpg_status = STRBUF_INIT;
int status;
sigc->result = 'N';
if (parse_signed_commit(commit->object.sha1,
&payload, &signature) <= 0)
goto out;
status = verify_signed_buffer(payload.buf, payload.len,
signature.buf, signature.len,
&gpg_output, &gpg_status);
if (status && !gpg_output.len)
goto out;
sigc->gpg_output = strbuf_detach(&gpg_output, NULL);
sigc->gpg_status = strbuf_detach(&gpg_status, NULL);
parse_gpg_output(sigc);
out:
strbuf_release(&gpg_status);
strbuf_release(&gpg_output);
strbuf_release(&payload);
strbuf_release(&signature);
}
void append_merge_tag_headers(struct commit_list *parents,
struct commit_extra_header ***tail)
{
while (parents) {
struct commit *parent = parents->item;
handle_signed_tag(parent, tail);
parents = parents->next;
}
}
static void add_extra_header(struct strbuf *buffer,
struct commit_extra_header *extra)
{
strbuf_addstr(buffer, extra->key);
if (extra->len)
strbuf_add_lines(buffer, " ", extra->value, extra->len);
else
strbuf_addch(buffer, '\n');
}
struct commit_extra_header *read_commit_extra_headers(struct commit *commit,
const char **exclude)
{
struct commit_extra_header *extra = NULL;
unsigned long size;
enum object_type type;
char *buffer = read_sha1_file(commit->object.sha1, &type, &size);
if (buffer && type == OBJ_COMMIT)
extra = read_commit_extra_header_lines(buffer, size, exclude);
free(buffer);
return extra;
}
static inline int standard_header_field(const char *field, size_t len)
{
return ((len == 4 && !memcmp(field, "tree ", 5)) ||
(len == 6 && !memcmp(field, "parent ", 7)) ||
(len == 6 && !memcmp(field, "author ", 7)) ||
(len == 9 && !memcmp(field, "committer ", 10)) ||
(len == 8 && !memcmp(field, "encoding ", 9)));
}
static int excluded_header_field(const char *field, size_t len, const char **exclude)
{
if (!exclude)
return 0;
while (*exclude) {
size_t xlen = strlen(*exclude);
if (len == xlen &&
!memcmp(field, *exclude, xlen) && field[xlen] == ' ')
return 1;
exclude++;
}
return 0;
}
static struct commit_extra_header *read_commit_extra_header_lines(
const char *buffer, size_t size,
const char **exclude)
{
struct commit_extra_header *extra = NULL, **tail = &extra, *it = NULL;
const char *line, *next, *eof, *eob;
struct strbuf buf = STRBUF_INIT;
for (line = buffer, eob = line + size;
line < eob && *line != '\n';
line = next) {
next = memchr(line, '\n', eob - line);
next = next ? next + 1 : eob;
if (*line == ' ') {
/* continuation */
if (it)
strbuf_add(&buf, line + 1, next - (line + 1));
continue;
}
if (it)
it->value = strbuf_detach(&buf, &it->len);
strbuf_reset(&buf);
it = NULL;
eof = strchr(line, ' ');
if (next <= eof)
eof = next;
if (standard_header_field(line, eof - line) ||
excluded_header_field(line, eof - line, exclude))
continue;
it = xcalloc(1, sizeof(*it));
it->key = xmemdupz(line, eof-line);
*tail = it;
tail = &it->next;
if (eof + 1 < next)
strbuf_add(&buf, eof + 1, next - (eof + 1));
}
if (it)
it->value = strbuf_detach(&buf, &it->len);
return extra;
}
void free_commit_extra_headers(struct commit_extra_header *extra)
{
while (extra) {
struct commit_extra_header *next = extra->next;
free(extra->key);
free(extra->value);
free(extra);
extra = next;
}
}
int commit_tree(const struct strbuf *msg, unsigned char *tree,
struct commit_list *parents, unsigned char *ret,
const char *author, const char *sign_commit)
{
struct commit_extra_header *extra = NULL, **tail = &extra;
int result;
append_merge_tag_headers(parents, &tail);
result = commit_tree_extended(msg, tree, parents, ret,
author, sign_commit, extra);
free_commit_extra_headers(extra);
return result;
}
static int find_invalid_utf8(const char *buf, int len)
{
int offset = 0;
static const unsigned int max_codepoint[] = {
0x7f, 0x7ff, 0xffff, 0x10ffff
};
while (len) {
unsigned char c = *buf++;
int bytes, bad_offset;
unsigned int codepoint;
unsigned int min_val, max_val;
len--;
offset++;
/* Simple US-ASCII? No worries. */
if (c < 0x80)
continue;
bad_offset = offset-1;
/*
* Count how many more high bits set: that's how
* many more bytes this sequence should have.
*/
bytes = 0;
while (c & 0x40) {
c <<= 1;
bytes++;
}
/*
* Must be between 1 and 3 more bytes. Longer sequences result in
* codepoints beyond U+10FFFF, which are guaranteed never to exist.
*/
if (bytes < 1 || 3 < bytes)
return bad_offset;
/* Do we *have* that many bytes? */
if (len < bytes)
return bad_offset;
/*
* Place the encoded bits at the bottom of the value and compute the
* valid range.
*/
codepoint = (c & 0x7f) >> bytes;
min_val = max_codepoint[bytes-1] + 1;
max_val = max_codepoint[bytes];
offset += bytes;
len -= bytes;
/* And verify that they are good continuation bytes */
do {
codepoint <<= 6;
codepoint |= *buf & 0x3f;
if ((*buf++ & 0xc0) != 0x80)
return bad_offset;
} while (--bytes);
/* Reject codepoints that are out of range for the sequence length. */
if (codepoint < min_val || codepoint > max_val)
return bad_offset;
/* Surrogates are only for UTF-16 and cannot be encoded in UTF-8. */
if ((codepoint & 0x1ff800) == 0xd800)
return bad_offset;
/* U+xxFFFE and U+xxFFFF are guaranteed non-characters. */
if ((codepoint & 0xfffe) == 0xfffe)
return bad_offset;
/* So are anything in the range U+FDD0..U+FDEF. */
if (codepoint >= 0xfdd0 && codepoint <= 0xfdef)
return bad_offset;
}
return -1;
}
/*
* This verifies that the buffer is in proper utf8 format.
*
* If it isn't, it assumes any non-utf8 characters are Latin1,
* and does the conversion.
*/
static int verify_utf8(struct strbuf *buf)
{
int ok = 1;
long pos = 0;
for (;;) {
int bad;
unsigned char c;
unsigned char replace[2];
bad = find_invalid_utf8(buf->buf + pos, buf->len - pos);
if (bad < 0)
return ok;
pos += bad;
ok = 0;
c = buf->buf[pos];
strbuf_remove(buf, pos, 1);
/* We know 'c' must be in the range 128-255 */
replace[0] = 0xc0 + (c >> 6);
replace[1] = 0x80 + (c & 0x3f);
strbuf_insert(buf, pos, replace, 2);
pos += 2;
}
}
static const char commit_utf8_warn[] =
"Warning: commit message did not conform to UTF-8.\n"
"You may want to amend it after fixing the message, or set the config\n"
"variable i18n.commitencoding to the encoding your project uses.\n";
int commit_tree_extended(const struct strbuf *msg, unsigned char *tree,
struct commit_list *parents, unsigned char *ret,
const char *author, const char *sign_commit,
struct commit_extra_header *extra)
{
int result;
int encoding_is_utf8;
struct strbuf buffer;
assert_sha1_type(tree, OBJ_TREE);
if (memchr(msg->buf, '\0', msg->len))
return error("a NUL byte in commit log message not allowed.");
/* Not having i18n.commitencoding is the same as having utf-8 */
encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
strbuf_addf(&buffer, "tree %s\n", sha1_to_hex(tree));
/*
* NOTE! This ordering means that the same exact tree merged with a
* different order of parents will be a _different_ changeset even
* if everything else stays the same.
*/
while (parents) {
struct commit_list *next = parents->next;
struct commit *parent = parents->item;
strbuf_addf(&buffer, "parent %s\n",
sha1_to_hex(parent->object.sha1));
free(parents);
parents = next;
}
/* Person/date information */
if (!author)
author = git_author_info(IDENT_STRICT);
strbuf_addf(&buffer, "author %s\n", author);
strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_STRICT));
if (!encoding_is_utf8)
strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
while (extra) {
add_extra_header(&buffer, extra);
extra = extra->next;
}
strbuf_addch(&buffer, '\n');
/* And add the comment */
strbuf_addbuf(&buffer, msg);
/* And check the encoding */
if (encoding_is_utf8 && !verify_utf8(&buffer))
fprintf(stderr, commit_utf8_warn);
if (sign_commit && do_sign_commit(&buffer, sign_commit))
return -1;
result = write_sha1_file(buffer.buf, buffer.len, commit_type, ret);
strbuf_release(&buffer);
return result;
}
struct commit *get_merge_parent(const char *name)
{
struct object *obj;
struct commit *commit;
unsigned char sha1[20];
if (get_sha1(name, sha1))
return NULL;
obj = parse_object(sha1);
commit = (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
if (commit && !commit->util) {
struct merge_remote_desc *desc;
desc = xmalloc(sizeof(*desc));
desc->obj = obj;
desc->name = strdup(name);
commit->util = desc;
}
return commit;
}
/*
* Append a commit to the end of the commit_list.
*
* next starts by pointing to the variable that holds the head of an
* empty commit_list, and is updated to point to the "next" field of
* the last item on the list as new commits are appended.
*
* Usage example:
*
* struct commit_list *list;
* struct commit_list **next = &list;
*
* next = commit_list_append(c1, next);
* next = commit_list_append(c2, next);
* assert(commit_list_count(list) == 2);
* return list;
*/
struct commit_list **commit_list_append(struct commit *commit,
struct commit_list **next)
{
struct commit_list *new = xmalloc(sizeof(struct commit_list));
new->item = commit;
*next = new;
new->next = NULL;
return &new->next;
}
void print_commit_list(struct commit_list *list,
const char *format_cur,
const char *format_last)
{
for ( ; list; list = list->next) {
const char *format = list->next ? format_cur : format_last;
printf(format, sha1_to_hex(list->item->object.sha1));
}
}