git/refs.c
Michael Haggerty 4c4de89573 do_for_each_ref(): reimplement using reference iteration
Use the reference iterator interface to implement do_for_each_ref().
Delete a bunch of code supporting the old for_each_ref() implementation.
And now that do_for_each_ref() is generic code (it is no longer tied to
the files backend), move it to refs.c.

The implementation is via a new function, do_for_each_ref_iterator(),
which takes a reference iterator as argument and calls a callback
function for each of the references in the iterator.

This change requires the current_ref performance hack for peel_ref() to
be implemented via ref_iterator_peel() rather than peel_entry() because
we don't have a ref_entry handy (it is hidden under three layers:
file_ref_iterator, merge_ref_iterator, and cache_ref_iterator). So:

* do_for_each_ref_iterator() records the active iterator in
  current_ref_iter while it is running.

* peel_ref() checks whether current_ref_iter is pointing at the
  requested reference. If so, it asks the iterator to peel the
  reference (which it can do efficiently via its "peel" virtual
  function). For extra safety, we do the optimization only if the
  refname *addresses* are the same, not only if the refname *strings*
  are the same, to forestall possible mixups between refnames that come
  from different ref_iterators.

Please note that this optimization of peel_ref() is only available when
iterating via do_for_each_ref_iterator() (including all of the
for_each_ref() functions, which call it indirectly). It would be
complicated to implement a similar optimization when iterating directly
using a reference iterator, because multiple reference iterators can be
in use at the same time, with interleaved calls to
ref_iterator_advance(). (In fact we do exactly that in
merge_ref_iterator.)

But that is not necessary. peel_ref() is only called while iterating
over references. Callers who iterate using the for_each_ref() functions
benefit from the optimization described above. Callers who iterate using
reference iterators directly have access to the ref_iterator, so they
can call ref_iterator_peel() themselves to get an analogous optimization
in a more straightforward manner.

If we rewrite all callers to use the reference iteration API, then we
can remove the current_ref_iter hack permanently.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-20 11:38:20 -07:00

1268 lines
30 KiB
C

/*
* The backend-independent part of the reference module.
*/
#include "cache.h"
#include "lockfile.h"
#include "refs.h"
#include "refs/refs-internal.h"
#include "object.h"
#include "tag.h"
/*
* How to handle various characters in refnames:
* 0: An acceptable character for refs
* 1: End-of-component
* 2: ., look for a preceding . to reject .. in refs
* 3: {, look for a preceding @ to reject @{ in refs
* 4: A bad character: ASCII control characters, and
* ":", "?", "[", "\", "^", "~", SP, or TAB
* 5: *, reject unless REFNAME_REFSPEC_PATTERN is set
*/
static unsigned char refname_disposition[256] = {
1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 1,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
};
/*
* Try to read one refname component from the front of refname.
* Return the length of the component found, or -1 if the component is
* not legal. It is legal if it is something reasonable to have under
* ".git/refs/"; We do not like it if:
*
* - any path component of it begins with ".", or
* - it has double dots "..", or
* - it has ASCII control characters, or
* - it has ":", "?", "[", "\", "^", "~", SP, or TAB anywhere, or
* - it has "*" anywhere unless REFNAME_REFSPEC_PATTERN is set, or
* - it ends with a "/", or
* - it ends with ".lock", or
* - it contains a "@{" portion
*/
static int check_refname_component(const char *refname, int *flags)
{
const char *cp;
char last = '\0';
for (cp = refname; ; cp++) {
int ch = *cp & 255;
unsigned char disp = refname_disposition[ch];
switch (disp) {
case 1:
goto out;
case 2:
if (last == '.')
return -1; /* Refname contains "..". */
break;
case 3:
if (last == '@')
return -1; /* Refname contains "@{". */
break;
case 4:
return -1;
case 5:
if (!(*flags & REFNAME_REFSPEC_PATTERN))
return -1; /* refspec can't be a pattern */
/*
* Unset the pattern flag so that we only accept
* a single asterisk for one side of refspec.
*/
*flags &= ~ REFNAME_REFSPEC_PATTERN;
break;
}
last = ch;
}
out:
if (cp == refname)
return 0; /* Component has zero length. */
if (refname[0] == '.')
return -1; /* Component starts with '.'. */
if (cp - refname >= LOCK_SUFFIX_LEN &&
!memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN))
return -1; /* Refname ends with ".lock". */
return cp - refname;
}
int check_refname_format(const char *refname, int flags)
{
int component_len, component_count = 0;
if (!strcmp(refname, "@"))
/* Refname is a single character '@'. */
return -1;
while (1) {
/* We are at the start of a path component. */
component_len = check_refname_component(refname, &flags);
if (component_len <= 0)
return -1;
component_count++;
if (refname[component_len] == '\0')
break;
/* Skip to next component. */
refname += component_len + 1;
}
if (refname[component_len - 1] == '.')
return -1; /* Refname ends with '.'. */
if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2)
return -1; /* Refname has only one component. */
return 0;
}
int refname_is_safe(const char *refname)
{
const char *rest;
if (skip_prefix(refname, "refs/", &rest)) {
char *buf;
int result;
size_t restlen = strlen(rest);
/* rest must not be empty, or start or end with "/" */
if (!restlen || *rest == '/' || rest[restlen - 1] == '/')
return 0;
/*
* Does the refname try to escape refs/?
* For example: refs/foo/../bar is safe but refs/foo/../../bar
* is not.
*/
buf = xmallocz(restlen);
result = !normalize_path_copy(buf, rest) && !strcmp(buf, rest);
free(buf);
return result;
}
do {
if (!isupper(*refname) && *refname != '_')
return 0;
refname++;
} while (*refname);
return 1;
}
char *resolve_refdup(const char *refname, int resolve_flags,
unsigned char *sha1, int *flags)
{
return xstrdup_or_null(resolve_ref_unsafe(refname, resolve_flags,
sha1, flags));
}
/* The argument to filter_refs */
struct ref_filter {
const char *pattern;
each_ref_fn *fn;
void *cb_data;
};
int read_ref_full(const char *refname, int resolve_flags, unsigned char *sha1, int *flags)
{
if (resolve_ref_unsafe(refname, resolve_flags, sha1, flags))
return 0;
return -1;
}
int read_ref(const char *refname, unsigned char *sha1)
{
return read_ref_full(refname, RESOLVE_REF_READING, sha1, NULL);
}
int ref_exists(const char *refname)
{
unsigned char sha1[20];
return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, sha1, NULL);
}
static int filter_refs(const char *refname, const struct object_id *oid,
int flags, void *data)
{
struct ref_filter *filter = (struct ref_filter *)data;
if (wildmatch(filter->pattern, refname, 0, NULL))
return 0;
return filter->fn(refname, oid, flags, filter->cb_data);
}
enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)
{
struct object *o = lookup_unknown_object(name);
if (o->type == OBJ_NONE) {
int type = sha1_object_info(name, NULL);
if (type < 0 || !object_as_type(o, type, 0))
return PEEL_INVALID;
}
if (o->type != OBJ_TAG)
return PEEL_NON_TAG;
o = deref_tag_noverify(o);
if (!o)
return PEEL_INVALID;
hashcpy(sha1, o->oid.hash);
return PEEL_PEELED;
}
struct warn_if_dangling_data {
FILE *fp;
const char *refname;
const struct string_list *refnames;
const char *msg_fmt;
};
static int warn_if_dangling_symref(const char *refname, const struct object_id *oid,
int flags, void *cb_data)
{
struct warn_if_dangling_data *d = cb_data;
const char *resolves_to;
struct object_id junk;
if (!(flags & REF_ISSYMREF))
return 0;
resolves_to = resolve_ref_unsafe(refname, 0, junk.hash, NULL);
if (!resolves_to
|| (d->refname
? strcmp(resolves_to, d->refname)
: !string_list_has_string(d->refnames, resolves_to))) {
return 0;
}
fprintf(d->fp, d->msg_fmt, refname);
fputc('\n', d->fp);
return 0;
}
void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
{
struct warn_if_dangling_data data;
data.fp = fp;
data.refname = refname;
data.refnames = NULL;
data.msg_fmt = msg_fmt;
for_each_rawref(warn_if_dangling_symref, &data);
}
void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
{
struct warn_if_dangling_data data;
data.fp = fp;
data.refname = NULL;
data.refnames = refnames;
data.msg_fmt = msg_fmt;
for_each_rawref(warn_if_dangling_symref, &data);
}
int for_each_tag_ref(each_ref_fn fn, void *cb_data)
{
return for_each_ref_in("refs/tags/", fn, cb_data);
}
int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
{
return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
}
int for_each_branch_ref(each_ref_fn fn, void *cb_data)
{
return for_each_ref_in("refs/heads/", fn, cb_data);
}
int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
{
return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);
}
int for_each_remote_ref(each_ref_fn fn, void *cb_data)
{
return for_each_ref_in("refs/remotes/", fn, cb_data);
}
int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
{
return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);
}
int head_ref_namespaced(each_ref_fn fn, void *cb_data)
{
struct strbuf buf = STRBUF_INIT;
int ret = 0;
struct object_id oid;
int flag;
strbuf_addf(&buf, "%sHEAD", get_git_namespace());
if (!read_ref_full(buf.buf, RESOLVE_REF_READING, oid.hash, &flag))
ret = fn(buf.buf, &oid, flag, cb_data);
strbuf_release(&buf);
return ret;
}
int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
const char *prefix, void *cb_data)
{
struct strbuf real_pattern = STRBUF_INIT;
struct ref_filter filter;
int ret;
if (!prefix && !starts_with(pattern, "refs/"))
strbuf_addstr(&real_pattern, "refs/");
else if (prefix)
strbuf_addstr(&real_pattern, prefix);
strbuf_addstr(&real_pattern, pattern);
if (!has_glob_specials(pattern)) {
/* Append implied '/' '*' if not present. */
strbuf_complete(&real_pattern, '/');
/* No need to check for '*', there is none. */
strbuf_addch(&real_pattern, '*');
}
filter.pattern = real_pattern.buf;
filter.fn = fn;
filter.cb_data = cb_data;
ret = for_each_ref(filter_refs, &filter);
strbuf_release(&real_pattern);
return ret;
}
int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
{
return for_each_glob_ref_in(fn, pattern, NULL, cb_data);
}
const char *prettify_refname(const char *name)
{
return name + (
starts_with(name, "refs/heads/") ? 11 :
starts_with(name, "refs/tags/") ? 10 :
starts_with(name, "refs/remotes/") ? 13 :
0);
}
static const char *ref_rev_parse_rules[] = {
"%.*s",
"refs/%.*s",
"refs/tags/%.*s",
"refs/heads/%.*s",
"refs/remotes/%.*s",
"refs/remotes/%.*s/HEAD",
NULL
};
int refname_match(const char *abbrev_name, const char *full_name)
{
const char **p;
const int abbrev_name_len = strlen(abbrev_name);
for (p = ref_rev_parse_rules; *p; p++) {
if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
return 1;
}
}
return 0;
}
/*
* *string and *len will only be substituted, and *string returned (for
* later free()ing) if the string passed in is a magic short-hand form
* to name a branch.
*/
static char *substitute_branch_name(const char **string, int *len)
{
struct strbuf buf = STRBUF_INIT;
int ret = interpret_branch_name(*string, *len, &buf);
if (ret == *len) {
size_t size;
*string = strbuf_detach(&buf, &size);
*len = size;
return (char *)*string;
}
return NULL;
}
int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
{
char *last_branch = substitute_branch_name(&str, &len);
const char **p, *r;
int refs_found = 0;
*ref = NULL;
for (p = ref_rev_parse_rules; *p; p++) {
char fullref[PATH_MAX];
unsigned char sha1_from_ref[20];
unsigned char *this_result;
int flag;
this_result = refs_found ? sha1_from_ref : sha1;
mksnpath(fullref, sizeof(fullref), *p, len, str);
r = resolve_ref_unsafe(fullref, RESOLVE_REF_READING,
this_result, &flag);
if (r) {
if (!refs_found++)
*ref = xstrdup(r);
if (!warn_ambiguous_refs)
break;
} else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {
warning("ignoring dangling symref %s.", fullref);
} else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {
warning("ignoring broken ref %s.", fullref);
}
}
free(last_branch);
return refs_found;
}
int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
{
char *last_branch = substitute_branch_name(&str, &len);
const char **p;
int logs_found = 0;
*log = NULL;
for (p = ref_rev_parse_rules; *p; p++) {
unsigned char hash[20];
char path[PATH_MAX];
const char *ref, *it;
mksnpath(path, sizeof(path), *p, len, str);
ref = resolve_ref_unsafe(path, RESOLVE_REF_READING,
hash, NULL);
if (!ref)
continue;
if (reflog_exists(path))
it = path;
else if (strcmp(ref, path) && reflog_exists(ref))
it = ref;
else
continue;
if (!logs_found++) {
*log = xstrdup(it);
hashcpy(sha1, hash);
}
if (!warn_ambiguous_refs)
break;
}
free(last_branch);
return logs_found;
}
static int is_per_worktree_ref(const char *refname)
{
return !strcmp(refname, "HEAD") ||
starts_with(refname, "refs/bisect/");
}
static int is_pseudoref_syntax(const char *refname)
{
const char *c;
for (c = refname; *c; c++) {
if (!isupper(*c) && *c != '-' && *c != '_')
return 0;
}
return 1;
}
enum ref_type ref_type(const char *refname)
{
if (is_per_worktree_ref(refname))
return REF_TYPE_PER_WORKTREE;
if (is_pseudoref_syntax(refname))
return REF_TYPE_PSEUDOREF;
return REF_TYPE_NORMAL;
}
static int write_pseudoref(const char *pseudoref, const unsigned char *sha1,
const unsigned char *old_sha1, struct strbuf *err)
{
const char *filename;
int fd;
static struct lock_file lock;
struct strbuf buf = STRBUF_INIT;
int ret = -1;
strbuf_addf(&buf, "%s\n", sha1_to_hex(sha1));
filename = git_path("%s", pseudoref);
fd = hold_lock_file_for_update(&lock, filename, LOCK_DIE_ON_ERROR);
if (fd < 0) {
strbuf_addf(err, "could not open '%s' for writing: %s",
filename, strerror(errno));
return -1;
}
if (old_sha1) {
unsigned char actual_old_sha1[20];
if (read_ref(pseudoref, actual_old_sha1))
die("could not read ref '%s'", pseudoref);
if (hashcmp(actual_old_sha1, old_sha1)) {
strbuf_addf(err, "unexpected sha1 when writing '%s'", pseudoref);
rollback_lock_file(&lock);
goto done;
}
}
if (write_in_full(fd, buf.buf, buf.len) != buf.len) {
strbuf_addf(err, "could not write to '%s'", filename);
rollback_lock_file(&lock);
goto done;
}
commit_lock_file(&lock);
ret = 0;
done:
strbuf_release(&buf);
return ret;
}
static int delete_pseudoref(const char *pseudoref, const unsigned char *old_sha1)
{
static struct lock_file lock;
const char *filename;
filename = git_path("%s", pseudoref);
if (old_sha1 && !is_null_sha1(old_sha1)) {
int fd;
unsigned char actual_old_sha1[20];
fd = hold_lock_file_for_update(&lock, filename,
LOCK_DIE_ON_ERROR);
if (fd < 0)
die_errno(_("Could not open '%s' for writing"), filename);
if (read_ref(pseudoref, actual_old_sha1))
die("could not read ref '%s'", pseudoref);
if (hashcmp(actual_old_sha1, old_sha1)) {
warning("Unexpected sha1 when deleting %s", pseudoref);
rollback_lock_file(&lock);
return -1;
}
unlink(filename);
rollback_lock_file(&lock);
} else {
unlink(filename);
}
return 0;
}
int delete_ref(const char *refname, const unsigned char *old_sha1,
unsigned int flags)
{
struct ref_transaction *transaction;
struct strbuf err = STRBUF_INIT;
if (ref_type(refname) == REF_TYPE_PSEUDOREF)
return delete_pseudoref(refname, old_sha1);
transaction = ref_transaction_begin(&err);
if (!transaction ||
ref_transaction_delete(transaction, refname, old_sha1,
flags, NULL, &err) ||
ref_transaction_commit(transaction, &err)) {
error("%s", err.buf);
ref_transaction_free(transaction);
strbuf_release(&err);
return 1;
}
ref_transaction_free(transaction);
strbuf_release(&err);
return 0;
}
int copy_reflog_msg(char *buf, const char *msg)
{
char *cp = buf;
char c;
int wasspace = 1;
*cp++ = '\t';
while ((c = *msg++)) {
if (wasspace && isspace(c))
continue;
wasspace = isspace(c);
if (wasspace)
c = ' ';
*cp++ = c;
}
while (buf < cp && isspace(cp[-1]))
cp--;
*cp++ = '\n';
return cp - buf;
}
int should_autocreate_reflog(const char *refname)
{
if (!log_all_ref_updates)
return 0;
return starts_with(refname, "refs/heads/") ||
starts_with(refname, "refs/remotes/") ||
starts_with(refname, "refs/notes/") ||
!strcmp(refname, "HEAD");
}
int is_branch(const char *refname)
{
return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
}
struct read_ref_at_cb {
const char *refname;
unsigned long at_time;
int cnt;
int reccnt;
unsigned char *sha1;
int found_it;
unsigned char osha1[20];
unsigned char nsha1[20];
int tz;
unsigned long date;
char **msg;
unsigned long *cutoff_time;
int *cutoff_tz;
int *cutoff_cnt;
};
static int read_ref_at_ent(unsigned char *osha1, unsigned char *nsha1,
const char *email, unsigned long timestamp, int tz,
const char *message, void *cb_data)
{
struct read_ref_at_cb *cb = cb_data;
cb->reccnt++;
cb->tz = tz;
cb->date = timestamp;
if (timestamp <= cb->at_time || cb->cnt == 0) {
if (cb->msg)
*cb->msg = xstrdup(message);
if (cb->cutoff_time)
*cb->cutoff_time = timestamp;
if (cb->cutoff_tz)
*cb->cutoff_tz = tz;
if (cb->cutoff_cnt)
*cb->cutoff_cnt = cb->reccnt - 1;
/*
* we have not yet updated cb->[n|o]sha1 so they still
* hold the values for the previous record.
*/
if (!is_null_sha1(cb->osha1)) {
hashcpy(cb->sha1, nsha1);
if (hashcmp(cb->osha1, nsha1))
warning("Log for ref %s has gap after %s.",
cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
}
else if (cb->date == cb->at_time)
hashcpy(cb->sha1, nsha1);
else if (hashcmp(nsha1, cb->sha1))
warning("Log for ref %s unexpectedly ended on %s.",
cb->refname, show_date(cb->date, cb->tz,
DATE_MODE(RFC2822)));
hashcpy(cb->osha1, osha1);
hashcpy(cb->nsha1, nsha1);
cb->found_it = 1;
return 1;
}
hashcpy(cb->osha1, osha1);
hashcpy(cb->nsha1, nsha1);
if (cb->cnt > 0)
cb->cnt--;
return 0;
}
static int read_ref_at_ent_oldest(unsigned char *osha1, unsigned char *nsha1,
const char *email, unsigned long timestamp,
int tz, const char *message, void *cb_data)
{
struct read_ref_at_cb *cb = cb_data;
if (cb->msg)
*cb->msg = xstrdup(message);
if (cb->cutoff_time)
*cb->cutoff_time = timestamp;
if (cb->cutoff_tz)
*cb->cutoff_tz = tz;
if (cb->cutoff_cnt)
*cb->cutoff_cnt = cb->reccnt;
hashcpy(cb->sha1, osha1);
if (is_null_sha1(cb->sha1))
hashcpy(cb->sha1, nsha1);
/* We just want the first entry */
return 1;
}
int read_ref_at(const char *refname, unsigned int flags, unsigned long at_time, int cnt,
unsigned char *sha1, char **msg,
unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
{
struct read_ref_at_cb cb;
memset(&cb, 0, sizeof(cb));
cb.refname = refname;
cb.at_time = at_time;
cb.cnt = cnt;
cb.msg = msg;
cb.cutoff_time = cutoff_time;
cb.cutoff_tz = cutoff_tz;
cb.cutoff_cnt = cutoff_cnt;
cb.sha1 = sha1;
for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
if (!cb.reccnt) {
if (flags & GET_SHA1_QUIETLY)
exit(128);
else
die("Log for %s is empty.", refname);
}
if (cb.found_it)
return 0;
for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
return 1;
}
struct ref_transaction *ref_transaction_begin(struct strbuf *err)
{
assert(err);
return xcalloc(1, sizeof(struct ref_transaction));
}
void ref_transaction_free(struct ref_transaction *transaction)
{
int i;
if (!transaction)
return;
for (i = 0; i < transaction->nr; i++) {
free(transaction->updates[i]->msg);
free(transaction->updates[i]);
}
free(transaction->updates);
free(transaction);
}
struct ref_update *ref_transaction_add_update(
struct ref_transaction *transaction,
const char *refname, unsigned int flags,
const unsigned char *new_sha1,
const unsigned char *old_sha1,
const char *msg)
{
struct ref_update *update;
if (transaction->state != REF_TRANSACTION_OPEN)
die("BUG: update called for transaction that is not open");
if ((flags & REF_ISPRUNING) && !(flags & REF_NODEREF))
die("BUG: REF_ISPRUNING set without REF_NODEREF");
FLEX_ALLOC_STR(update, refname, refname);
ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
transaction->updates[transaction->nr++] = update;
update->flags = flags;
if (flags & REF_HAVE_NEW)
hashcpy(update->new_sha1, new_sha1);
if (flags & REF_HAVE_OLD)
hashcpy(update->old_sha1, old_sha1);
if (msg)
update->msg = xstrdup(msg);
return update;
}
int ref_transaction_update(struct ref_transaction *transaction,
const char *refname,
const unsigned char *new_sha1,
const unsigned char *old_sha1,
unsigned int flags, const char *msg,
struct strbuf *err)
{
assert(err);
if ((new_sha1 && !is_null_sha1(new_sha1)) ?
check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
!refname_is_safe(refname)) {
strbuf_addf(err, "refusing to update ref with bad name '%s'",
refname);
return -1;
}
flags |= (new_sha1 ? REF_HAVE_NEW : 0) | (old_sha1 ? REF_HAVE_OLD : 0);
ref_transaction_add_update(transaction, refname, flags,
new_sha1, old_sha1, msg);
return 0;
}
int ref_transaction_create(struct ref_transaction *transaction,
const char *refname,
const unsigned char *new_sha1,
unsigned int flags, const char *msg,
struct strbuf *err)
{
if (!new_sha1 || is_null_sha1(new_sha1))
die("BUG: create called without valid new_sha1");
return ref_transaction_update(transaction, refname, new_sha1,
null_sha1, flags, msg, err);
}
int ref_transaction_delete(struct ref_transaction *transaction,
const char *refname,
const unsigned char *old_sha1,
unsigned int flags, const char *msg,
struct strbuf *err)
{
if (old_sha1 && is_null_sha1(old_sha1))
die("BUG: delete called with old_sha1 set to zeros");
return ref_transaction_update(transaction, refname,
null_sha1, old_sha1,
flags, msg, err);
}
int ref_transaction_verify(struct ref_transaction *transaction,
const char *refname,
const unsigned char *old_sha1,
unsigned int flags,
struct strbuf *err)
{
if (!old_sha1)
die("BUG: verify called with old_sha1 set to NULL");
return ref_transaction_update(transaction, refname,
NULL, old_sha1,
flags, NULL, err);
}
int update_ref(const char *msg, const char *refname,
const unsigned char *new_sha1, const unsigned char *old_sha1,
unsigned int flags, enum action_on_err onerr)
{
struct ref_transaction *t = NULL;
struct strbuf err = STRBUF_INIT;
int ret = 0;
if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
ret = write_pseudoref(refname, new_sha1, old_sha1, &err);
} else {
t = ref_transaction_begin(&err);
if (!t ||
ref_transaction_update(t, refname, new_sha1, old_sha1,
flags, msg, &err) ||
ref_transaction_commit(t, &err)) {
ret = 1;
ref_transaction_free(t);
}
}
if (ret) {
const char *str = "update_ref failed for ref '%s': %s";
switch (onerr) {
case UPDATE_REFS_MSG_ON_ERR:
error(str, refname, err.buf);
break;
case UPDATE_REFS_DIE_ON_ERR:
die(str, refname, err.buf);
break;
case UPDATE_REFS_QUIET_ON_ERR:
break;
}
strbuf_release(&err);
return 1;
}
strbuf_release(&err);
if (t)
ref_transaction_free(t);
return 0;
}
char *shorten_unambiguous_ref(const char *refname, int strict)
{
int i;
static char **scanf_fmts;
static int nr_rules;
char *short_name;
if (!nr_rules) {
/*
* Pre-generate scanf formats from ref_rev_parse_rules[].
* Generate a format suitable for scanf from a
* ref_rev_parse_rules rule by interpolating "%s" at the
* location of the "%.*s".
*/
size_t total_len = 0;
size_t offset = 0;
/* the rule list is NULL terminated, count them first */
for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)
/* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */
total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;
scanf_fmts = xmalloc(st_add(st_mult(nr_rules, sizeof(char *)), total_len));
offset = 0;
for (i = 0; i < nr_rules; i++) {
assert(offset < total_len);
scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;
offset += snprintf(scanf_fmts[i], total_len - offset,
ref_rev_parse_rules[i], 2, "%s") + 1;
}
}
/* bail out if there are no rules */
if (!nr_rules)
return xstrdup(refname);
/* buffer for scanf result, at most refname must fit */
short_name = xstrdup(refname);
/* skip first rule, it will always match */
for (i = nr_rules - 1; i > 0 ; --i) {
int j;
int rules_to_fail = i;
int short_name_len;
if (1 != sscanf(refname, scanf_fmts[i], short_name))
continue;
short_name_len = strlen(short_name);
/*
* in strict mode, all (except the matched one) rules
* must fail to resolve to a valid non-ambiguous ref
*/
if (strict)
rules_to_fail = nr_rules;
/*
* check if the short name resolves to a valid ref,
* but use only rules prior to the matched one
*/
for (j = 0; j < rules_to_fail; j++) {
const char *rule = ref_rev_parse_rules[j];
char refname[PATH_MAX];
/* skip matched rule */
if (i == j)
continue;
/*
* the short name is ambiguous, if it resolves
* (with this previous rule) to a valid ref
* read_ref() returns 0 on success
*/
mksnpath(refname, sizeof(refname),
rule, short_name_len, short_name);
if (ref_exists(refname))
break;
}
/*
* short name is non-ambiguous if all previous rules
* haven't resolved to a valid ref
*/
if (j == rules_to_fail)
return short_name;
}
free(short_name);
return xstrdup(refname);
}
static struct string_list *hide_refs;
int parse_hide_refs_config(const char *var, const char *value, const char *section)
{
if (!strcmp("transfer.hiderefs", var) ||
/* NEEDSWORK: use parse_config_key() once both are merged */
(starts_with(var, section) && var[strlen(section)] == '.' &&
!strcmp(var + strlen(section), ".hiderefs"))) {
char *ref;
int len;
if (!value)
return config_error_nonbool(var);
ref = xstrdup(value);
len = strlen(ref);
while (len && ref[len - 1] == '/')
ref[--len] = '\0';
if (!hide_refs) {
hide_refs = xcalloc(1, sizeof(*hide_refs));
hide_refs->strdup_strings = 1;
}
string_list_append(hide_refs, ref);
}
return 0;
}
int ref_is_hidden(const char *refname, const char *refname_full)
{
int i;
if (!hide_refs)
return 0;
for (i = hide_refs->nr - 1; i >= 0; i--) {
const char *match = hide_refs->items[i].string;
const char *subject;
int neg = 0;
int len;
if (*match == '!') {
neg = 1;
match++;
}
if (*match == '^') {
subject = refname_full;
match++;
} else {
subject = refname;
}
/* refname can be NULL when namespaces are used. */
if (!subject || !starts_with(subject, match))
continue;
len = strlen(match);
if (!subject[len] || subject[len] == '/')
return !neg;
}
return 0;
}
const char *find_descendant_ref(const char *dirname,
const struct string_list *extras,
const struct string_list *skip)
{
int pos;
if (!extras)
return NULL;
/*
* Look at the place where dirname would be inserted into
* extras. If there is an entry at that position that starts
* with dirname (remember, dirname includes the trailing
* slash) and is not in skip, then we have a conflict.
*/
for (pos = string_list_find_insert_index(extras, dirname, 0);
pos < extras->nr; pos++) {
const char *extra_refname = extras->items[pos].string;
if (!starts_with(extra_refname, dirname))
break;
if (!skip || !string_list_has_string(skip, extra_refname))
return extra_refname;
}
return NULL;
}
int rename_ref_available(const char *oldname, const char *newname)
{
struct string_list skip = STRING_LIST_INIT_NODUP;
struct strbuf err = STRBUF_INIT;
int ret;
string_list_insert(&skip, oldname);
ret = !verify_refname_available(newname, NULL, &skip, &err);
if (!ret)
error("%s", err.buf);
string_list_clear(&skip, 0);
strbuf_release(&err);
return ret;
}
int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
{
struct object_id oid;
int flag;
if (submodule) {
if (resolve_gitlink_ref(submodule, "HEAD", oid.hash) == 0)
return fn("HEAD", &oid, 0, cb_data);
return 0;
}
if (!read_ref_full("HEAD", RESOLVE_REF_READING, oid.hash, &flag))
return fn("HEAD", &oid, flag, cb_data);
return 0;
}
int head_ref(each_ref_fn fn, void *cb_data)
{
return head_ref_submodule(NULL, fn, cb_data);
}
/*
* Call fn for each reference in the specified submodule for which the
* refname begins with prefix. If trim is non-zero, then trim that
* many characters off the beginning of each refname before passing
* the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
* include broken references in the iteration. If fn ever returns a
* non-zero value, stop the iteration and return that value;
* otherwise, return 0.
*/
static int do_for_each_ref(const char *submodule, const char *prefix,
each_ref_fn fn, int trim, int flags, void *cb_data)
{
struct ref_iterator *iter;
iter = files_ref_iterator_begin(submodule, prefix, flags);
iter = prefix_ref_iterator_begin(iter, prefix, trim);
return do_for_each_ref_iterator(iter, fn, cb_data);
}
int for_each_ref(each_ref_fn fn, void *cb_data)
{
return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
}
int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
{
return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
}
int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
{
return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);
}
int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
{
unsigned int flag = 0;
if (broken)
flag = DO_FOR_EACH_INCLUDE_BROKEN;
return do_for_each_ref(NULL, prefix, fn, 0, flag, cb_data);
}
int for_each_ref_in_submodule(const char *submodule, const char *prefix,
each_ref_fn fn, void *cb_data)
{
return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);
}
int for_each_replace_ref(each_ref_fn fn, void *cb_data)
{
return do_for_each_ref(NULL, git_replace_ref_base, fn,
strlen(git_replace_ref_base), 0, cb_data);
}
int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
{
struct strbuf buf = STRBUF_INIT;
int ret;
strbuf_addf(&buf, "%srefs/", get_git_namespace());
ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
strbuf_release(&buf);
return ret;
}
int for_each_rawref(each_ref_fn fn, void *cb_data)
{
return do_for_each_ref(NULL, "", fn, 0,
DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
}
/* This function needs to return a meaningful errno on failure */
const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
unsigned char *sha1, int *flags)
{
static struct strbuf sb_refname = STRBUF_INIT;
int unused_flags;
int symref_count;
if (!flags)
flags = &unused_flags;
*flags = 0;
if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
!refname_is_safe(refname)) {
errno = EINVAL;
return NULL;
}
/*
* dwim_ref() uses REF_ISBROKEN to distinguish between
* missing refs and refs that were present but invalid,
* to complain about the latter to stderr.
*
* We don't know whether the ref exists, so don't set
* REF_ISBROKEN yet.
*/
*flags |= REF_BAD_NAME;
}
for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
unsigned int read_flags = 0;
if (read_raw_ref(refname, sha1, &sb_refname, &read_flags)) {
*flags |= read_flags;
if (errno != ENOENT || (resolve_flags & RESOLVE_REF_READING))
return NULL;
hashclr(sha1);
if (*flags & REF_BAD_NAME)
*flags |= REF_ISBROKEN;
return refname;
}
*flags |= read_flags;
if (!(read_flags & REF_ISSYMREF)) {
if (*flags & REF_BAD_NAME) {
hashclr(sha1);
*flags |= REF_ISBROKEN;
}
return refname;
}
refname = sb_refname.buf;
if (resolve_flags & RESOLVE_REF_NO_RECURSE) {
hashclr(sha1);
return refname;
}
if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) ||
!refname_is_safe(refname)) {
errno = EINVAL;
return NULL;
}
*flags |= REF_ISBROKEN | REF_BAD_NAME;
}
}
errno = ELOOP;
return NULL;
}