#define USE_THE_REPOSITORY_VARIABLE

#include "git-compat-util.h"

#include "tag.h"

#include "commit.h"

#include "commit-graph.h"

#include "environment.h"

#include "gettext.h"

#include "hex.h"

#include "repository.h"

#include "object-name.h"

#include "object-store.h"

#include "utf8.h"

#include "diff.h"

#include "revision.h"

#include "notes.h"

#include "alloc.h"

#include "gpg-interface.h"

#include "mergesort.h"

#include "commit-slab.h"

#include "prio-queue.h"

#include "hash-lookup.h"

#include "wt-status.h"

#include "advice.h"

#include "refs.h"

#include "commit-reach.h"

#include "setup.h"

#include "shallow.h"

#include "tree.h"

#include "hook.h"

#include "parse.h"

#include "object-file.h"

#include "object-file-convert.h"

static struct commit_extra_header *read_commit_extra_header_lines(const char *buf, size_t len, const char **);

int save_commit_buffer = 1;

int no_graft_file_deprecated_advice;

const char *commit_type = "commit";

struct commit *lookup_commit_reference_gently(struct repository *r,

const struct object_id *oid, int quiet)

{

struct object *obj = deref_tag(r,

parse_object(r, oid),

NULL, 0);

if (!obj)

return NULL;

return object_as_type(obj, OBJ_COMMIT, quiet);

}

struct commit *lookup_commit_reference(struct repository *r, const struct object_id *oid)

{

return lookup_commit_reference_gently(r, oid, 0);

}

struct commit *lookup_commit_or_die(const struct object_id *oid, const char *ref_name)

{

struct commit *c = lookup_commit_reference(the_repository, oid);

if (!c)

die(_("could not parse %s"), ref_name);

if (!oideq(oid, &c->object.oid)) {

warning(_("%s %s is not a commit!"),

ref_name, oid_to_hex(oid));

}

return c;

}

struct commit *lookup_commit_object(struct repository *r,

const struct object_id *oid)

{

struct object *obj = parse_object(r, oid);

return obj ? object_as_type(obj, OBJ_COMMIT, 0) : NULL;

}

struct commit *lookup_commit(struct repository *r, const struct object_id *oid)

{

struct object *obj = lookup_object(r, oid);

if (!obj)

return create_object(r, oid, alloc_commit_node(r));

return object_as_type(obj, OBJ_COMMIT, 0);

}

struct commit *lookup_commit_reference_by_name(const char *name)

{

return lookup_commit_reference_by_name_gently(name, 0);

}

struct commit *lookup_commit_reference_by_name_gently(const char *name,

int quiet)

{

struct object_id oid;

struct commit *commit;

if (repo_get_oid_committish(the_repository, name, &oid))

return NULL;

commit = lookup_commit_reference_gently(the_repository, &oid, quiet);

if (repo_parse_commit(the_repository, commit))

return NULL;

return commit;

}

static timestamp_t parse_commit_date(const char *buf, const char *tail)

{

const char *dateptr;

const char *eol;

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;

/*

* Jump to end-of-line so that we can walk backwards to find the

* end-of-email ">". This is more forgiving of malformed cases

* because unexpected characters tend to be in the name and email

* fields.

*/

eol = memchr(buf, '\n', tail - buf);

if (!eol)

return 0;

dateptr = eol;

while (dateptr > buf && dateptr[-1] != '>')

dateptr--;

if (dateptr == buf)

return 0;

/*

* Trim leading whitespace, but make sure we have at least one

* non-whitespace character, as parse_timestamp() will otherwise walk

* right past the newline we found in "eol" when skipping whitespace

* itself.

*

* In theory it would be sufficient to allow any character not matched

* by isspace(), but there's a catch: our isspace() does not

* necessarily match the behavior of parse_timestamp(), as the latter

* is implemented by system routines which match more exotic control

* codes, or even locale-dependent sequences.

*

* Since we expect the timestamp to be a number, we can check for that.

* Anything else (e.g., a non-numeric token like "foo") would just

* cause parse_timestamp() to return 0 anyway.

*/

while (dateptr < eol && isspace(*dateptr))

dateptr++;

if (!isdigit(*dateptr) && *dateptr != '-')

return 0;

/*

* We know there is at least one digit (or dash), so we'll begin

* parsing there and stop at worst case at eol.

*

* Note that we may feed parse_timestamp() extra characters here if the

* commit is malformed, and it will parse as far as it can. For

* example, "123foo456" would return "123". That might be questionable

* (versus returning "0"), but it would help in a hypothetical case

* like "123456+0100", where the whitespace from the timezone is

* missing. Since such syntactic errors may be baked into history and

* hard to correct now, let's err on trying to make our best guess

* here, rather than insist on perfect syntax.

*/

return parse_timestamp(dateptr, NULL, 10);

}

static const struct object_id *commit_graft_oid_access(size_t index, const void *table)

{

const struct commit_graft * const *commit_graft_table = table;

return &commit_graft_table[index]->oid;

}

int commit_graft_pos(struct repository *r, const struct object_id *oid)

{

return oid_pos(oid, r->parsed_objects->grafts,

r->parsed_objects->grafts_nr,

commit_graft_oid_access);

}

void unparse_commit(struct repository *r, const struct object_id *oid)

{

struct commit *c = lookup_commit(r, oid);

if (!c->object.parsed)

return;

free_commit_list(c->parents);

c->parents = NULL;

c->object.parsed = 0;

}

int register_commit_graft(struct repository *r, struct commit_graft *graft,

int ignore_dups)

{

int pos = commit_graft_pos(r, &graft->oid);

if (0 <= pos) {

if (ignore_dups)

free(graft);

else {

free(r->parsed_objects->grafts[pos]);

r->parsed_objects->grafts[pos] = graft;

}

return 1;

}

pos = -pos - 1;

ALLOC_GROW(r->parsed_objects->grafts,

r->parsed_objects->grafts_nr + 1,

r->parsed_objects->grafts_alloc);

r->parsed_objects->grafts_nr++;

if (pos < r->parsed_objects->grafts_nr)

memmove(r->parsed_objects->grafts + pos + 1,

r->parsed_objects->grafts + pos,

(r->parsed_objects->grafts_nr - pos - 1) *

sizeof(*r->parsed_objects->grafts));

r->parsed_objects->grafts[pos] = graft;

unparse_commit(r, &graft->oid);

return 0;

}

struct commit_graft *read_graft_line(struct strbuf *line)

{

/* The format is just "Commit Parent1 Parent2 ...\n" */

int i, phase;

const char *tail = NULL;

struct commit_graft *graft = NULL;

struct object_id dummy_oid, *oid;

strbuf_rtrim(line);

if (!line->len || line->buf[0] == '#')

return NULL;

/*

* phase 0 verifies line, counts hashes in line and allocates graft

* phase 1 fills graft

*/

for (phase = 0; phase < 2; phase++) {

oid = graft ? &graft->oid : &dummy_oid;

if (parse_oid_hex(line->buf, oid, &tail))

goto bad_graft_data;

for (i = 0; *tail != '\0'; i++) {

oid = graft ? &graft->parent[i] : &dummy_oid;

if (!isspace(*tail++) || parse_oid_hex(tail, oid, &tail))

goto bad_graft_data;

}

if (!graft) {

graft = xmalloc(st_add(sizeof(*graft),

st_mult(sizeof(struct object_id), i)));

graft->nr_parent = i;

}

}

return graft;

bad_graft_data:

error("bad graft data: %s", line->buf);

assert(!graft);

return NULL;

}

static int read_graft_file(struct repository *r, const char *graft_file)

{

FILE *fp = fopen_or_warn(graft_file, "r");

struct strbuf buf = STRBUF_INIT;

if (!fp)

return -1;

if (!no_graft_file_deprecated_advice &&

advice_enabled(ADVICE_GRAFT_FILE_DEPRECATED))

advise(_("Support for <GIT_DIR>/info/grafts is deprecated\n"

"and will be removed in a future Git version.\n"

"\n"

"Please use \"git replace --convert-graft-file\"\n"

"to convert the grafts into replace refs.\n"

"\n"

"Turn this message off by running\n"

"\"git config set advice.graftFileDeprecated false\""));

while (!strbuf_getwholeline(&buf, fp, '\n')) {

/* The format is just "Commit Parent1 Parent2 ...\n" */

struct commit_graft *graft = read_graft_line(&buf);

if (!graft)

continue;

if (register_commit_graft(r, graft, 1))

error("duplicate graft data: %s", buf.buf);

}

fclose(fp);

strbuf_release(&buf);

return 0;

}

void prepare_commit_graft(struct repository *r)

{

const char *graft_file;

if (r->parsed_objects->commit_graft_prepared)

return;

if (!startup_info->have_repository)

return;

graft_file = repo_get_graft_file(r);

read_graft_file(r, graft_file);

/* make sure shallows are read */

is_repository_shallow(r);

r->parsed_objects->commit_graft_prepared = 1;

}

struct commit_graft *lookup_commit_graft(struct repository *r, const struct object_id *oid)

{

int pos;

prepare_commit_graft(r);

pos = commit_graft_pos(r, oid);

if (pos < 0)

return NULL;

return r->parsed_objects->grafts[pos];

}

int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data)

{

int i, ret;

for (i = ret = 0; i < the_repository->parsed_objects->grafts_nr && !ret; i++)

ret = fn(the_repository->parsed_objects->grafts[i], cb_data);

return ret;

}

struct commit_buffer {

void *buffer;

unsigned long size;

};

define_commit_slab(buffer_slab, struct commit_buffer);

struct buffer_slab *allocate_commit_buffer_slab(void)

{

struct buffer_slab *bs = xmalloc(sizeof(*bs));

init_buffer_slab(bs);

return bs;

}

void free_commit_buffer_slab(struct buffer_slab *bs)

{

clear_buffer_slab(bs);

free(bs);

}

void set_commit_buffer(struct repository *r, struct commit *commit, void *buffer, unsigned long size)

{

struct commit_buffer *v = buffer_slab_at(

r->parsed_objects->buffer_slab, commit);

v->buffer = buffer;

v->size = size;

}

const void *get_cached_commit_buffer(struct repository *r, const struct commit *commit, unsigned long *sizep)

{

struct commit_buffer *v = buffer_slab_peek(

r->parsed_objects->buffer_slab, commit);

if (!v) {

if (sizep)

*sizep = 0;

return NULL;

}

if (sizep)

*sizep = v->size;

return v->buffer;

}

const void *repo_get_commit_buffer(struct repository *r,

const struct commit *commit,

unsigned long *sizep)

{

const void *ret = get_cached_commit_buffer(r, commit, sizep);

if (!ret) {

enum object_type type;

unsigned long size;

ret = repo_read_object_file(r, &commit->object.oid, &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), type_name(type));

if (sizep)

*sizep = size;

}

return ret;

}

void repo_unuse_commit_buffer(struct repository *r,

const struct commit *commit,

const void *buffer)

{

struct commit_buffer *v = buffer_slab_peek(

r->parsed_objects->buffer_slab, commit);

if (!(v && v->buffer == buffer))

free((void *)buffer);

}

void free_commit_buffer(struct parsed_object_pool *pool, struct commit *commit)

{

struct commit_buffer *v = buffer_slab_peek(

pool->buffer_slab, commit);

if (v) {

FREE_AND_NULL(v->buffer);

v->size = 0;

}

}

static inline void set_commit_tree(struct commit *c, struct tree *t)

{

c->maybe_tree = t;

}

struct tree *repo_get_commit_tree(struct repository *r,

const struct commit *commit)

{

if (commit->maybe_tree || !commit->object.parsed)

return commit->maybe_tree;

if (commit_graph_position(commit) != COMMIT_NOT_FROM_GRAPH)

return get_commit_tree_in_graph(r, commit);

return NULL;

}

struct object_id *get_commit_tree_oid(const struct commit *commit)

{

struct tree *tree = repo_get_commit_tree(the_repository, commit);

return tree ? &tree->object.oid : NULL;

}

void release_commit_memory(struct parsed_object_pool *pool, struct commit *c)

{

set_commit_tree(c, NULL);

free_commit_buffer(pool, c);

c->index = 0;

free_commit_list(c->parents);

c->object.parsed = 0;

}

const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep)

{

struct commit_buffer *v = buffer_slab_peek(

the_repository->parsed_objects->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 repository *r, struct commit *item, const void *buffer, unsigned long size, int check_graph)

{

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 = the_hash_algo->hexsz + 5;

const int parent_entry_len = the_hash_algo->hexsz + 7;

struct tree *tree;

if (item->object.parsed)

return 0;

/*

* Presumably this is leftover from an earlier failed parse;

* clear it out in preparation for us re-parsing (we'll hit the

* same error, but that's good, since it lets our caller know

* the result cannot be trusted.

*/

free_commit_list(item->parents);

item->parents = NULL;

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_oid_hex(bufptr + 5, &parent) < 0)

return error("bad tree pointer in commit %s",

oid_to_hex(&item->object.oid));

tree = lookup_tree(r, &parent);

if (!tree)

return error("bad tree pointer %s in commit %s",

oid_to_hex(&parent),

oid_to_hex(&item->object.oid));

set_commit_tree(item, tree);

bufptr += tree_entry_len + 1; /* "tree " + "hex sha1" + "\n" */

pptr = &item->parents;

graft = lookup_commit_graft(r, &item->object.oid);

if (graft)

r->parsed_objects->substituted_parent = 1;

while (bufptr + parent_entry_len < tail && !memcmp(bufptr, "parent ", 7)) {

struct commit *new_parent;

if (tail <= bufptr + parent_entry_len + 1 ||

get_oid_hex(bufptr + 7, &parent) ||

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_keep_true_parents))

continue;

new_parent = lookup_commit(r, &parent);

if (!new_parent)

return error("bad parent %s in commit %s",

oid_to_hex(&parent),

oid_to_hex(&item->object.oid));

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(r,

&graft->parent[i]);

if (!new_parent)

return error("bad graft parent %s in commit %s",

oid_to_hex(&graft->parent[i]),

oid_to_hex(&item->object.oid));

pptr = &commit_list_insert(new_parent, pptr)->next;

}

}

item->date = parse_commit_date(bufptr, tail);

if (check_graph)

load_commit_graph_info(r, item);

item->object.parsed = 1;

return 0;

}

int repo_parse_commit_internal(struct repository *r,

struct commit *item,

int quiet_on_missing,

int use_commit_graph)

{

enum object_type type;

void *buffer;

unsigned long size;

struct object_info oi = {

.typep = &type,

.sizep = &size,

.contentp = &buffer,

};

/*

* Git does not support partial clones that exclude commits, so set

* OBJECT_INFO_SKIP_FETCH_OBJECT to fail fast when an object is missing.

*/

int flags = OBJECT_INFO_LOOKUP_REPLACE | OBJECT_INFO_SKIP_FETCH_OBJECT |

OBJECT_INFO_DIE_IF_CORRUPT;

int ret;

if (!item)

return -1;

if (item->object.parsed)

return 0;

if (use_commit_graph && parse_commit_in_graph(r, item)) {

static int commit_graph_paranoia = -1;

if (commit_graph_paranoia == -1)

commit_graph_paranoia = git_env_bool(GIT_COMMIT_GRAPH_PARANOIA, 0);

if (commit_graph_paranoia && !has_object(r, &item->object.oid, 0)) {

unparse_commit(r, &item->object.oid);

return quiet_on_missing ? -1 :

error(_("commit %s exists in commit-graph but not in the object database"),

oid_to_hex(&item->object.oid));

}

return 0;

}

if (oid_object_info_extended(r, &item->object.oid, &oi, flags) < 0)

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(r, item, buffer, size, 0);

if (save_commit_buffer && !ret &&

!get_cached_commit_buffer(r, item, NULL)) {

set_commit_buffer(r, item, buffer, size);

return 0;

}

free(buffer);

return ret;

}

int repo_parse_commit_gently(struct repository *r,

struct commit *item, int quiet_on_missing)

{

return repo_parse_commit_internal(r, item, quiet_on_missing, 1);

}

void parse_commit_or_die(struct commit *item)

{

if (repo_parse_commit(the_repository, 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 = skip_blank_lines(p + 2);

eol = strchrnul(p, '\n');

} else

eol = p;

*subject = p;

return eol - p;

}

size_t commit_subject_length(const char *body)

{

const char *p = body;

while (*p) {

const char *next = skip_blank_lines(p);

if (next != p)

break;

p = strchrnul(p, '\n');

if (*p)

p++;

}

return p - body;

}

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;

}

int commit_list_contains(struct commit *item, struct commit_list *list)

{

while (list) {

if (list->item == item)

return 1;

list = list->next;

}

return 0;

}

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(const 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;

}

struct commit_list *reverse_commit_list(struct commit_list *list)

{

struct commit_list *next = NULL, *current, *backup;

for (current = list; current; current = backup) {

backup = current->next;

current->next = next;

next = current;

}

return next;

}

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 struct commit_list *a,

const struct commit_list *b)

{

timestamp_t a_date = a->item->date;

timestamp_t b_date = b->item->date;

if (a_date < b_date)

return 1;

if (a_date > b_date)

return -1;

return 0;

}

DEFINE_LIST_SORT(static, commit_list_sort, struct commit_list, next);

void commit_list_sort_by_date(struct commit_list **list)

{

commit_list_sort(list, 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 (!repo_parse_commit(the_repository, 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)) {

if (parents->item->object.flags & mark)

commit_list_insert(parents->item, plist);

}

commit = commit->parents->item;

}

}

void clear_commit_marks_many(size_t nr, struct commit **commit, unsigned int mark)

{

for (size_t i = 0; i < nr; i++)

clear_commit_marks(commit[i], mark);

}

void clear_commit_marks(struct commit *commit, unsigned int mark)

{

struct commit_list *list = NULL;

clear_commit_marks_1(&list, commit, mark);

while (list)

clear_commit_marks_1(&list, pop_commit(&list), 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);

define_commit_slab(author_date_slab, timestamp_t);

void record_author_date(struct author_date_slab *author_date,

struct commit *commit)

{

const char *buffer = repo_get_commit_buffer(the_repository, commit,

NULL);

struct ident_split ident;

const char *ident_line;

size_t ident_len;

char *date_end;

timestamp_t 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 = parse_timestamp(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:

repo_unuse_commit_buffer(the_repository, commit, buffer);

}

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;

timestamp_t a_date = *(author_date_slab_at(author_date, a));

timestamp_t 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_gen_then_commit_date(const void *a_, const void *b_,

void *unused UNUSED)

{

const struct commit *a = a_, *b = b_;

const timestamp_t generation_a = commit_graph_generation(a),

generation_b = commit_graph_generation(b);

/* newer commits first */

if (generation_a < generation_b)

return 1;

else if (generation_a > generation_b)

return -1;

/* use date as a heuristic when generations are equal */

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 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;

}