git/refs.c
Jeff King 6cd4a8982d avoid using mksnpath for refs
Like the previous commit, we'd like to avoid the assumption
that refs fit into PATH_MAX-sized buffers. These callsites
have an extra twist, though: they write the refnames using
mksnpath. This does two things beyond a regular snprintf:

  1. It quietly writes "/bad-path/" when truncation occurs.
     This saves the caller having to check the error code,
     but if you aren't actually feeding the result to a
     system call (and we aren't here), it's questionable.

  2. It calls cleanup_path(), which removes leading
     instances of "./".  That's questionable when dealing
     with refnames, as we could silently canonicalize a
     syntactically bogus refname into a valid one.

Let's convert each case to use a strbuf. This is preferable
to xstrfmt() because we can reuse the same buffer as we
loop.

Signed-off-by: Jeff King <peff@peff.net>
2017-03-30 14:59:50 -07:00

1624 lines
39 KiB
C

/*
* The backend-independent part of the reference module.
*/
#include "cache.h"
#include "hashmap.h"
#include "lockfile.h"
#include "refs.h"
#include "refs/refs-internal.h"
#include "object.h"
#include "tag.h"
/*
* List of all available backends
*/
static struct ref_storage_be *refs_backends = &refs_be_files;
static struct ref_storage_be *find_ref_storage_backend(const char *name)
{
struct ref_storage_be *be;
for (be = refs_backends; be; be = be->next)
if (!strcmp(be->name, name))
return be;
return NULL;
}
int ref_storage_backend_exists(const char *name)
{
return find_ref_storage_backend(name) != NULL;
}
/*
* 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)
{
if (skip_prefix(name, "refs/heads/", &name) ||
skip_prefix(name, "refs/tags/", &name) ||
skip_prefix(name, "refs/remotes/", &name))
; /* nothing */
return name;
}
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, 0);
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);
int refs_found = expand_ref(str, len, sha1, ref);
free(last_branch);
return refs_found;
}
int expand_ref(const char *str, int len, unsigned char *sha1, char **ref)
{
const char **p, *r;
int refs_found = 0;
struct strbuf fullref = STRBUF_INIT;
*ref = NULL;
for (p = ref_rev_parse_rules; *p; p++) {
unsigned char sha1_from_ref[20];
unsigned char *this_result;
int flag;
this_result = refs_found ? sha1_from_ref : sha1;
strbuf_reset(&fullref);
strbuf_addf(&fullref, *p, len, str);
r = resolve_ref_unsafe(fullref.buf, 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.buf, "HEAD")) {
warning("ignoring dangling symref %s.", fullref.buf);
} else if ((flag & REF_ISBROKEN) && strchr(fullref.buf, '/')) {
warning("ignoring broken ref %s.", fullref.buf);
}
}
strbuf_release(&fullref);
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;
struct strbuf path = STRBUF_INIT;
*log = NULL;
for (p = ref_rev_parse_rules; *p; p++) {
unsigned char hash[20];
const char *ref, *it;
strbuf_reset(&path);
strbuf_addf(&path, *p, len, str);
ref = resolve_ref_unsafe(path.buf, RESOLVE_REF_READING,
hash, NULL);
if (!ref)
continue;
if (reflog_exists(path.buf))
it = path.buf;
else if (strcmp(ref, path.buf) && reflog_exists(ref))
it = ref;
else
continue;
if (!logs_found++) {
*log = xstrdup(it);
hashcpy(sha1, hash);
}
if (!warn_ambiguous_refs)
break;
}
strbuf_release(&path);
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 *msg, 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, msg, &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)
{
switch (log_all_ref_updates) {
case LOG_REFS_ALWAYS:
return 1;
case LOG_REFS_NORMAL:
return starts_with(refname, "refs/heads/") ||
starts_with(refname, "refs/remotes/") ||
starts_with(refname, "refs/notes/") ||
!strcmp(refname, "HEAD");
default:
return 0;
}
}
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(struct object_id *ooid, struct object_id *noid,
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, noid->hash);
if (hashcmp(cb->osha1, noid->hash))
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, noid->hash);
else if (hashcmp(noid->hash, 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, ooid->hash);
hashcpy(cb->nsha1, noid->hash);
cb->found_it = 1;
return 1;
}
hashcpy(cb->osha1, ooid->hash);
hashcpy(cb->nsha1, noid->hash);
if (cb->cnt > 0)
cb->cnt--;
return 0;
}
static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
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, ooid->hash);
if (is_null_sha1(cb->sha1))
hashcpy(cb->sha1, noid->hash);
/* 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);
update->msg = xstrdup_or_null(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_oid(const char *msg, const char *refname,
const struct object_id *new_oid, const struct object_id *old_oid,
unsigned int flags, enum action_on_err onerr)
{
return update_ref(msg, refname, new_oid ? new_oid->hash : NULL,
old_oid ? old_oid->hash : NULL, flags, onerr);
}
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;
struct strbuf resolved_buf = STRBUF_INIT;
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(sizeof(char *), nr_rules), 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];
/* 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
*/
strbuf_reset(&resolved_buf);
strbuf_addf(&resolved_buf, rule,
short_name_len, short_name);
if (ref_exists(resolved_buf.buf))
break;
}
/*
* short name is non-ambiguous if all previous rules
* haven't resolved to a valid ref
*/
if (j == rules_to_fail) {
strbuf_release(&resolved_buf);
return short_name;
}
}
strbuf_release(&resolved_buf);
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)
{
const char *key;
if (!strcmp("transfer.hiderefs", var) ||
(!parse_config_key(var, section, NULL, NULL, &key) &&
!strcmp(key, "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 *old_refname, const char *new_refname)
{
struct string_list skip = STRING_LIST_INIT_NODUP;
struct strbuf err = STRBUF_INIT;
int ok;
string_list_insert(&skip, old_refname);
ok = !verify_refname_available(new_refname, NULL, &skip, &err);
if (!ok)
error("%s", err.buf);
string_list_clear(&skip, 0);
strbuf_release(&err);
return ok;
}
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_store *refs = get_ref_store(submodule);
struct ref_iterator *iter;
if (!refs)
return 0;
iter = refs->be->iterator_begin(refs, 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_recursively(struct ref_store *refs,
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 (refs->be->read_raw_ref(refs, 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;
}
/* backend functions */
int refs_init_db(struct strbuf *err)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->init_db(refs, err);
}
const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
unsigned char *sha1, int *flags)
{
return resolve_ref_recursively(get_ref_store(NULL), refname,
resolve_flags, sha1, flags);
}
int resolve_gitlink_ref(const char *submodule, const char *refname,
unsigned char *sha1)
{
size_t len = strlen(submodule);
struct ref_store *refs;
int flags;
while (len && submodule[len - 1] == '/')
len--;
if (!len)
return -1;
if (submodule[len]) {
/* We need to strip off one or more trailing slashes */
char *stripped = xmemdupz(submodule, len);
refs = get_ref_store(stripped);
free(stripped);
} else {
refs = get_ref_store(submodule);
}
if (!refs)
return -1;
if (!resolve_ref_recursively(refs, refname, 0, sha1, &flags) ||
is_null_sha1(sha1))
return -1;
return 0;
}
struct submodule_hash_entry
{
struct hashmap_entry ent; /* must be the first member! */
struct ref_store *refs;
/* NUL-terminated name of submodule: */
char submodule[FLEX_ARRAY];
};
static int submodule_hash_cmp(const void *entry, const void *entry_or_key,
const void *keydata)
{
const struct submodule_hash_entry *e1 = entry, *e2 = entry_or_key;
const char *submodule = keydata ? keydata : e2->submodule;
return strcmp(e1->submodule, submodule);
}
static struct submodule_hash_entry *alloc_submodule_hash_entry(
const char *submodule, struct ref_store *refs)
{
struct submodule_hash_entry *entry;
FLEX_ALLOC_STR(entry, submodule, submodule);
hashmap_entry_init(entry, strhash(submodule));
entry->refs = refs;
return entry;
}
/* A pointer to the ref_store for the main repository: */
static struct ref_store *main_ref_store;
/* A hashmap of ref_stores, stored by submodule name: */
static struct hashmap submodule_ref_stores;
/*
* Return the ref_store instance for the specified submodule (or the
* main repository if submodule is NULL). If that ref_store hasn't
* been initialized yet, return NULL.
*/
static struct ref_store *lookup_ref_store(const char *submodule)
{
struct submodule_hash_entry *entry;
if (!submodule)
return main_ref_store;
if (!submodule_ref_stores.tablesize)
/* It's initialized on demand in register_ref_store(). */
return NULL;
entry = hashmap_get_from_hash(&submodule_ref_stores,
strhash(submodule), submodule);
return entry ? entry->refs : NULL;
}
/*
* Register the specified ref_store to be the one that should be used
* for submodule (or the main repository if submodule is NULL). It is
* a fatal error to call this function twice for the same submodule.
*/
static void register_ref_store(struct ref_store *refs, const char *submodule)
{
if (!submodule) {
if (main_ref_store)
die("BUG: main_ref_store initialized twice");
main_ref_store = refs;
} else {
if (!submodule_ref_stores.tablesize)
hashmap_init(&submodule_ref_stores, submodule_hash_cmp, 0);
if (hashmap_put(&submodule_ref_stores,
alloc_submodule_hash_entry(submodule, refs)))
die("BUG: ref_store for submodule '%s' initialized twice",
submodule);
}
}
/*
* Create, record, and return a ref_store instance for the specified
* submodule (or the main repository if submodule is NULL).
*/
static struct ref_store *ref_store_init(const char *submodule)
{
const char *be_name = "files";
struct ref_storage_be *be = find_ref_storage_backend(be_name);
struct ref_store *refs;
if (!be)
die("BUG: reference backend %s is unknown", be_name);
refs = be->init(submodule);
register_ref_store(refs, submodule);
return refs;
}
struct ref_store *get_ref_store(const char *submodule)
{
struct ref_store *refs;
if (!submodule || !*submodule) {
refs = lookup_ref_store(NULL);
if (!refs)
refs = ref_store_init(NULL);
} else {
refs = lookup_ref_store(submodule);
if (!refs) {
struct strbuf submodule_sb = STRBUF_INIT;
strbuf_addstr(&submodule_sb, submodule);
if (is_nonbare_repository_dir(&submodule_sb))
refs = ref_store_init(submodule);
strbuf_release(&submodule_sb);
}
}
return refs;
}
void base_ref_store_init(struct ref_store *refs,
const struct ref_storage_be *be)
{
refs->be = be;
}
/* backend functions */
int pack_refs(unsigned int flags)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->pack_refs(refs, flags);
}
int peel_ref(const char *refname, unsigned char *sha1)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->peel_ref(refs, refname, sha1);
}
int create_symref(const char *ref_target, const char *refs_heads_master,
const char *logmsg)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->create_symref(refs, ref_target, refs_heads_master,
logmsg);
}
int ref_transaction_commit(struct ref_transaction *transaction,
struct strbuf *err)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->transaction_commit(refs, transaction, err);
}
int verify_refname_available(const char *refname,
const struct string_list *extra,
const struct string_list *skip,
struct strbuf *err)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->verify_refname_available(refs, refname, extra, skip, err);
}
int for_each_reflog(each_ref_fn fn, void *cb_data)
{
struct ref_store *refs = get_ref_store(NULL);
struct ref_iterator *iter;
iter = refs->be->reflog_iterator_begin(refs);
return do_for_each_ref_iterator(iter, fn, cb_data);
}
int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn,
void *cb_data)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->for_each_reflog_ent_reverse(refs, refname,
fn, cb_data);
}
int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn,
void *cb_data)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data);
}
int reflog_exists(const char *refname)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->reflog_exists(refs, refname);
}
int safe_create_reflog(const char *refname, int force_create,
struct strbuf *err)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->create_reflog(refs, refname, force_create, err);
}
int delete_reflog(const char *refname)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->delete_reflog(refs, refname);
}
int reflog_expire(const char *refname, const unsigned char *sha1,
unsigned int flags,
reflog_expiry_prepare_fn prepare_fn,
reflog_expiry_should_prune_fn should_prune_fn,
reflog_expiry_cleanup_fn cleanup_fn,
void *policy_cb_data)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->reflog_expire(refs, refname, sha1, flags,
prepare_fn, should_prune_fn,
cleanup_fn, policy_cb_data);
}
int initial_ref_transaction_commit(struct ref_transaction *transaction,
struct strbuf *err)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->initial_transaction_commit(refs, transaction, err);
}
int delete_refs(struct string_list *refnames, unsigned int flags)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->delete_refs(refs, refnames, flags);
}
int rename_ref(const char *oldref, const char *newref, const char *logmsg)
{
struct ref_store *refs = get_ref_store(NULL);
return refs->be->rename_ref(refs, oldref, newref, logmsg);
}