git/commit.c
Jeff King 50a6c8efa2 use st_add and st_mult for allocation size computation
If our size computation overflows size_t, we may allocate a
much smaller buffer than we expected and overflow it. It's
probably impossible to trigger an overflow in most of these
sites in practice, but it is easy enough convert their
additions and multiplications into overflow-checking
variants. This may be fixing real bugs, and it makes
auditing the code easier.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 14:51:09 -08:00

1697 lines
41 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"
#include "sha1-lookup.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";
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 object_as_type(obj, OBJ_COMMIT, 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.oid.hash)) {
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)
return create_object(sha1, alloc_commit_node());
return object_as_type(obj, OBJ_COMMIT, 0);
}
struct commit *lookup_commit_reference_by_name(const char *name)
{
struct object_id oid;
struct commit *commit;
if (get_sha1_committish(name, oid.hash))
return NULL;
commit = lookup_commit_reference(oid.hash);
if (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 const unsigned char *commit_graft_sha1_access(size_t index, void *table)
{
struct commit_graft **commit_graft_table = table;
return commit_graft_table[index]->oid.hash;
}
static int commit_graft_pos(const unsigned char *sha1)
{
return sha1_pos(sha1, commit_graft, commit_graft_nr,
commit_graft_sha1_access);
}
int register_commit_graft(struct commit_graft *graft, int ignore_dups)
{
int pos = commit_graft_pos(graft->oid.hash);
if (0 <= pos) {
if (ignore_dups)
free(graft);
else {
free(commit_graft[pos]);
commit_graft[pos] = graft;
}
return 1;
}
pos = -pos - 1;
ALLOC_GROW(commit_graft, commit_graft_nr + 1, commit_graft_alloc);
commit_graft_nr++;
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;
const int entry_size = GIT_SHA1_HEXSZ + 1;
while (len && isspace(buf[len-1]))
buf[--len] = '\0';
if (buf[0] == '#' || buf[0] == '\0')
return NULL;
if ((len + 1) % entry_size)
goto bad_graft_data;
i = (len + 1) / entry_size - 1;
graft = xmalloc(st_add(sizeof(*graft), st_mult(GIT_SHA1_RAWSZ, i)));
graft->nr_parent = i;
if (get_oid_hex(buf, &graft->oid))
goto bad_graft_data;
for (i = GIT_SHA1_HEXSZ; i < len; i += entry_size) {
if (buf[i] != ' ')
goto bad_graft_data;
if (get_sha1_hex(buf + i + 1, graft->parent[i/entry_size].hash))
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");
struct strbuf buf = STRBUF_INIT;
if (!fp)
return -1;
while (!strbuf_getwholeline(&buf, fp, '\n')) {
/* The format is just "Commit Parent1 Parent2 ...\n" */
struct commit_graft *graft = read_graft_line(buf.buf, buf.len);
if (!graft)
continue;
if (register_commit_graft(graft, 1))
error("duplicate graft data: %s", buf.buf);
}
fclose(fp);
strbuf_release(&buf);
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;
}
struct commit_buffer {
void *buffer;
unsigned long size;
};
define_commit_slab(buffer_slab, struct commit_buffer);
static struct buffer_slab buffer_slab = COMMIT_SLAB_INIT(1, buffer_slab);
void set_commit_buffer(struct commit *commit, void *buffer, unsigned long size)
{
struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
v->buffer = buffer;
v->size = size;
}
const void *get_cached_commit_buffer(const struct commit *commit, unsigned long *sizep)
{
struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
if (!v) {
if (sizep)
*sizep = 0;
return NULL;
}
if (sizep)
*sizep = v->size;
return v->buffer;
}
const void *get_commit_buffer(const struct commit *commit, unsigned long *sizep)
{
const void *ret = get_cached_commit_buffer(commit, sizep);
if (!ret) {
enum object_type type;
unsigned long size;
ret = read_sha1_file(commit->object.oid.hash, &type, &size);
if (!ret)
die("cannot read commit object %s",
oid_to_hex(&commit->object.oid));
if (type != OBJ_COMMIT)
die("expected commit for %s, got %s",
oid_to_hex(&commit->object.oid), typename(type));
if (sizep)
*sizep = size;
}
return ret;
}
void unuse_commit_buffer(const struct commit *commit, const void *buffer)
{
struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
if (!(v && v->buffer == buffer))
free((void *)buffer);
}
void free_commit_buffer(struct commit *commit)
{
struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
if (v) {
free(v->buffer);
v->buffer = NULL;
v->size = 0;
}
}
const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep)
{
struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
void *ret;
if (!v) {
if (sizep)
*sizep = 0;
return NULL;
}
ret = v->buffer;
if (sizep)
*sizep = v->size;
v->buffer = NULL;
v->size = 0;
return ret;
}
int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size)
{
const char *tail = buffer;
const char *bufptr = buffer;
struct object_id parent;
struct commit_list **pptr;
struct commit_graft *graft;
const int tree_entry_len = GIT_SHA1_HEXSZ + 5;
const int parent_entry_len = GIT_SHA1_HEXSZ + 7;
if (item->object.parsed)
return 0;
item->object.parsed = 1;
tail += size;
if (tail <= bufptr + tree_entry_len + 1 || memcmp(bufptr, "tree ", 5) ||
bufptr[tree_entry_len] != '\n')
return error("bogus commit object %s", oid_to_hex(&item->object.oid));
if (get_sha1_hex(bufptr + 5, parent.hash) < 0)
return error("bad tree pointer in commit %s",
oid_to_hex(&item->object.oid));
item->tree = lookup_tree(parent.hash);
bufptr += tree_entry_len + 1; /* "tree " + "hex sha1" + "\n" */
pptr = &item->parents;
graft = lookup_commit_graft(item->object.oid.hash);
while (bufptr + parent_entry_len < tail && !memcmp(bufptr, "parent ", 7)) {
struct commit *new_parent;
if (tail <= bufptr + parent_entry_len + 1 ||
get_sha1_hex(bufptr + 7, parent.hash) ||
bufptr[parent_entry_len] != '\n')
return error("bad parents in commit %s", oid_to_hex(&item->object.oid));
bufptr += parent_entry_len + 1;
/*
* 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.hash);
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].hash);
if (!new_parent)
continue;
pptr = &commit_list_insert(new_parent, pptr)->next;
}
}
item->date = parse_commit_date(bufptr, tail);
return 0;
}
int parse_commit_gently(struct commit *item, int quiet_on_missing)
{
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.oid.hash, &type, &size);
if (!buffer)
return quiet_on_missing ? -1 :
error("Could not read %s",
oid_to_hex(&item->object.oid));
if (type != OBJ_COMMIT) {
free(buffer);
return error("Object %s not a commit",
oid_to_hex(&item->object.oid));
}
ret = parse_commit_buffer(item, buffer, size);
if (save_commit_buffer && !ret) {
set_commit_buffer(item, buffer, size);
return 0;
}
free(buffer);
return ret;
}
void parse_commit_or_die(struct commit *item)
{
if (parse_commit(item))
die("unable to parse commit %s",
item ? oid_to_hex(&item->object.oid) : "(null)");
}
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;
}
struct commit_list *copy_commit_list(struct commit_list *list)
{
struct commit_list *head = NULL;
struct commit_list **pp = &head;
while (list) {
pp = commit_list_append(list->item, pp);
list = list->next;
}
return head;
}
void free_commit_list(struct commit_list *list)
{
while (list)
pop_commit(&list);
}
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 = pop_commit(list);
struct commit_list *parents = ret->parents;
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->oid.hash, 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 *buffer = get_commit_buffer(commit, NULL);
struct ident_split ident;
const char *ident_line;
size_t ident_len;
char *date_end;
unsigned long date;
ident_line = find_commit_header(buffer, "author", &ident_len);
if (!ident_line)
goto fail_exit; /* no author line */
if (split_ident_line(&ident, ident_line, ident_len) ||
!ident.date_begin || !ident.date_end)
goto fail_exit; /* malformed "author" line */
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:
unuse_commit_buffer(commit, 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 */
/* Remember to update object flag allocation in object.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 int queue_has_nonstale(struct prio_queue *queue)
{
int i;
for (i = 0; i < queue->nr; i++) {
struct commit *commit = queue->array[i].data;
if (!(commit->object.flags & STALE))
return 1;
}
return 0;
}
/* 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 prio_queue queue = { compare_commits_by_commit_date };
struct commit_list *result = NULL;
int i;
one->object.flags |= PARENT1;
if (!n) {
commit_list_append(one, &result);
return result;
}
prio_queue_put(&queue, one);
for (i = 0; i < n; i++) {
twos[i]->object.flags |= PARENT2;
prio_queue_put(&queue, twos[i]);
}
while (queue_has_nonstale(&queue)) {
struct commit *commit = prio_queue_get(&queue);
struct commit_list *parents;
int flags;
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;
prio_queue_put(&queue, p);
}
}
clear_prio_queue(&queue);
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 *commit = pop_commit(&list);
if (!(commit->object.flags & STALE))
commit_list_insert_by_date(commit, &result);
}
return result;
}
struct commit_list *get_octopus_merge_bases(struct commit_list *in)
{
struct commit_list *i, *j, *k, *ret = NULL;
if (!in)
return ret;
commit_list_insert(in->item, &ret);
for (i = in->next; i; i = i->next) {
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);
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);
ALLOC_ARRAY(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;
}
static struct commit_list *get_merge_bases_many_0(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 = commit_list_count(result);
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_many(struct commit *one,
int n,
struct commit **twos)
{
return get_merge_bases_many_0(one, n, twos, 1);
}
struct commit_list *get_merge_bases_many_dirty(struct commit *one,
int n,
struct commit **twos)
{
return get_merge_bases_many_0(one, n, twos, 0);
}
struct commit_list *get_merge_bases(struct commit *one, struct commit *two)
{
return get_merge_bases_many_0(one, 1, &two, 1);
}
/*
* 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(num_head, sizeof(*array));
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 struct commit *commit,
struct strbuf *payload, struct strbuf *signature)
{
unsigned long size;
const char *buffer = get_commit_buffer(commit, &size);
int in_signature, saw_signature = -1;
const char *line, *tail;
line = buffer;
tail = buffer + size;
in_signature = 0;
saw_signature = 0;
while (line < tail) {
const char *sig = NULL;
const char *next = memchr(line, '\n', tail - line);
next = next ? next + 1 : tail;
if (in_signature && line[0] == ' ')
sig = line + 1;
else if (starts_with(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;
}
unuse_commit_buffer(commit, buffer);
return saw_signature;
}
int remove_signature(struct strbuf *buf)
{
const char *line = buf->buf;
const char *tail = buf->buf + buf->len;
int in_signature = 0;
const char *sig_start = NULL;
const char *sig_end = NULL;
while (line < tail) {
const char *next = memchr(line, '\n', tail - line);
next = next ? next + 1 : tail;
if (in_signature && line[0] == ' ')
sig_end = next;
else if (starts_with(line, gpg_sig_header) &&
line[gpg_sig_header_len] == ' ') {
sig_start = line;
sig_end = next;
in_signature = 1;
} else {
if (*line == '\n')
/* dump the whole remainder of the buffer */
next = tail;
in_signature = 0;
}
line = next;
}
if (sig_start)
strbuf_remove(buf, sig_start - buf->buf, sig_end - sig_start);
return sig_start != NULL;
}
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->oid.hash, &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);
}
int check_commit_signature(const struct commit *commit, struct signature_check *sigc)
{
struct strbuf payload = STRBUF_INIT;
struct strbuf signature = STRBUF_INIT;
int ret = 1;
sigc->result = 'N';
if (parse_signed_commit(commit, &payload, &signature) <= 0)
goto out;
ret = check_signature(payload.buf, payload.len, signature.buf,
signature.len, sigc);
out:
strbuf_release(&payload);
strbuf_release(&signature);
return ret;
}
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;
const char *buffer = get_commit_buffer(commit, &size);
extra = read_commit_extra_header_lines(buffer, size, exclude);
unuse_commit_buffer(commit, buffer);
return extra;
}
void for_each_mergetag(each_mergetag_fn fn, struct commit *commit, void *data)
{
struct commit_extra_header *extra, *to_free;
to_free = read_commit_extra_headers(commit, NULL);
for (extra = to_free; extra; extra = extra->next) {
if (strcmp(extra->key, "mergetag"))
continue; /* not a merge tag */
fn(commit, extra, data);
}
free_commit_extra_headers(to_free);
}
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 char *msg, size_t msg_len,
const 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, msg_len, 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 char *msg, size_t msg_len,
const 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, '\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 *parent = pop_commit(&parents);
strbuf_addf(&buffer, "parent %s\n",
oid_to_hex(&parent->object.oid));
}
/* 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_add(&buffer, msg, msg_len);
/* 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;
struct object_id oid;
if (get_sha1(name, oid.hash))
return NULL;
obj = parse_object(oid.hash);
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, oid_to_hex(&list->item->object.oid));
}
}
const char *find_commit_header(const char *msg, const char *key, size_t *out_len)
{
int key_len = strlen(key);
const char *line = msg;
while (line) {
const char *eol = strchrnul(line, '\n');
if (line == eol)
return NULL;
if (eol - line > key_len &&
!strncmp(line, key, key_len) &&
line[key_len] == ' ') {
*out_len = eol - line - key_len - 1;
return line + key_len + 1;
}
line = *eol ? eol + 1 : NULL;
}
return NULL;
}
/*
* Inspect sb and determine the true "end" of the log message, in
* order to find where to put a new Signed-off-by: line. Ignored are
* trailing comment lines and blank lines, and also the traditional
* "Conflicts:" block that is not commented out, so that we can use
* "git commit -s --amend" on an existing commit that forgot to remove
* it.
*
* Returns the number of bytes from the tail to ignore, to be fed as
* the second parameter to append_signoff().
*/
int ignore_non_trailer(struct strbuf *sb)
{
int boc = 0;
int bol = 0;
int in_old_conflicts_block = 0;
while (bol < sb->len) {
char *next_line;
if (!(next_line = memchr(sb->buf + bol, '\n', sb->len - bol)))
next_line = sb->buf + sb->len;
else
next_line++;
if (sb->buf[bol] == comment_line_char || sb->buf[bol] == '\n') {
/* is this the first of the run of comments? */
if (!boc)
boc = bol;
/* otherwise, it is just continuing */
} else if (starts_with(sb->buf + bol, "Conflicts:\n")) {
in_old_conflicts_block = 1;
if (!boc)
boc = bol;
} else if (in_old_conflicts_block && sb->buf[bol] == '\t') {
; /* a pathname in the conflicts block */
} else if (boc) {
/* the previous was not trailing comment */
boc = 0;
in_old_conflicts_block = 0;
}
bol = next_line - sb->buf;
}
return boc ? sb->len - boc : 0;
}