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#include "cache.h"
#include "refs.h"
#include "object.h"
#include "tag.h"
#include "dir.h"

/*
* Make sure "ref" 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 character, "~", "^", ":" or SP, anywhere, or
* - it ends with a "/".
* - it ends with ".lock"
* - it contains a "\" (backslash)
*/

/* Return true iff ch is not allowed in reference names. */
static inline int bad_ref_char(int ch)
{
if (((unsigned) ch) <= ' ' || ch == 0x7f ||
ch == '~' || ch == '^' || ch == ':' || ch == '\\')
return 1;
/* 2.13 Pattern Matching Notation */
if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
return 1;
return 0;
}

/*
* 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.
*/
static int check_refname_component(const char *refname, int flags)
{
const char *cp;
char last = '\0';

for (cp = refname; ; cp++) {
char ch = *cp;
if (ch == '\0' || ch == '/')
break;
if (bad_ref_char(ch))
return -1; /* Illegal character in refname. */
if (last == '.' && ch == '.')
return -1; /* Refname contains "..". */
if (last == '@' && ch == '{')
return -1; /* Refname contains "@{". */
last = ch;
}
if (cp == refname)
return 0; /* Component has zero length. */
if (refname[0] == '.') {
if (!(flags & REFNAME_DOT_COMPONENT))
return -1; /* Component starts with '.'. */
/*
* Even if leading dots are allowed, don't allow "."
* as a component (".." is prevented by a rule above).
*/
if (refname[1] == '\0')
return -1; /* Component equals ".". */
}
if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5))
return -1; /* Refname ends with ".lock". */
return cp - refname;
}

int check_refname_format(const char *refname, int flags)
{
int component_len, component_count = 0;

while (1) {
/* We are at the start of a path component. */
component_len = check_refname_component(refname, flags);
if (component_len <= 0) {
if ((flags & REFNAME_REFSPEC_PATTERN) &&
refname[0] == '*' &&
(refname[1] == '\0' || refname[1] == '/')) {
/* Accept one wildcard as a full refname component. */
flags &= ~REFNAME_REFSPEC_PATTERN;
component_len = 1;
} else {
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;
}

struct ref_entry;

/*
* Information used (along with the information in ref_entry) to
* describe a single cached reference. This data structure only
* occurs embedded in a union in struct ref_entry, and only when
* (ref_entry->flag & REF_DIR) is zero.
*/
struct ref_value {
unsigned char sha1[20];
unsigned char peeled[20];
};

struct ref_cache;

/*
* Information used (along with the information in ref_entry) to
* describe a level in the hierarchy of references. This data
* structure only occurs embedded in a union in struct ref_entry, and
* only when (ref_entry.flag & REF_DIR) is set. In that case,
* (ref_entry.flag & REF_INCOMPLETE) determines whether the references
* in the directory have already been read:
*
* (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose
* or packed references, already read.
*
* (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose
* references that hasn't been read yet (nor has any of its
* subdirectories).
*
* Entries within a directory are stored within a growable array of
* pointers to ref_entries (entries, nr, alloc). Entries 0 <= i <
* sorted are sorted by their component name in strcmp() order and the
* remaining entries are unsorted.
*
* Loose references are read lazily, one directory at a time. When a
* directory of loose references is read, then all of the references
* in that directory are stored, and REF_INCOMPLETE stubs are created
* for any subdirectories, but the subdirectories themselves are not
* read. The reading is triggered by get_ref_dir().
*/
struct ref_dir {
int nr, alloc;

/*
* Entries with index 0 <= i < sorted are sorted by name. New
* entries are appended to the list unsorted, and are sorted
* only when required; thus we avoid the need to sort the list
* after the addition of every reference.
*/
int sorted;

/* A pointer to the ref_cache that contains this ref_dir. */
struct ref_cache *ref_cache;

struct ref_entry **entries;
};

/* ISSYMREF=0x01, ISPACKED=0x02, and ISBROKEN=0x04 are public interfaces */
#define REF_KNOWS_PEELED 0x08

/* ref_entry represents a directory of references */
#define REF_DIR 0x10

/*
* Entry has not yet been read from disk (used only for REF_DIR
* entries representing loose references)
*/
#define REF_INCOMPLETE 0x20

/*
* A ref_entry represents either a reference or a "subdirectory" of
* references.
*
* Each directory in the reference namespace is represented by a
* ref_entry with (flags & REF_DIR) set and containing a subdir member
* that holds the entries in that directory that have been read so
* far. If (flags & REF_INCOMPLETE) is set, then the directory and
* its subdirectories haven't been read yet. REF_INCOMPLETE is only
* used for loose reference directories.
*
* References are represented by a ref_entry with (flags & REF_DIR)
* unset and a value member that describes the reference's value. The
* flag member is at the ref_entry level, but it is also needed to
* interpret the contents of the value field (in other words, a
* ref_value object is not very much use without the enclosing
* ref_entry).
*
* Reference names cannot end with slash and directories' names are
* always stored with a trailing slash (except for the top-level
* directory, which is always denoted by ""). This has two nice
* consequences: (1) when the entries in each subdir are sorted
* lexicographically by name (as they usually are), the references in
* a whole tree can be generated in lexicographic order by traversing
* the tree in left-to-right, depth-first order; (2) the names of
* references and subdirectories cannot conflict, and therefore the
* presence of an empty subdirectory does not block the creation of a
* similarly-named reference. (The fact that reference names with the
* same leading components can conflict *with each other* is a
* separate issue that is regulated by is_refname_available().)
*
* Please note that the name field contains the fully-qualified
* reference (or subdirectory) name. Space could be saved by only
* storing the relative names. But that would require the full names
* to be generated on the fly when iterating in do_for_each_ref(), and
* would break callback functions, who have always been able to assume
* that the name strings that they are passed will not be freed during
* the iteration.
*/
struct ref_entry {
unsigned char flag; /* ISSYMREF? ISPACKED? */
union {
struct ref_value value; /* if not (flags&REF_DIR) */
struct ref_dir subdir; /* if (flags&REF_DIR) */
} u;
/*
* The full name of the reference (e.g., "refs/heads/master")
* or the full name of the directory with a trailing slash
* (e.g., "refs/heads/"):
*/
char name[FLEX_ARRAY];
};

static void read_loose_refs(const char *dirname, struct ref_dir *dir);

static struct ref_dir *get_ref_dir(struct ref_entry *entry)
{
struct ref_dir *dir;
assert(entry->flag & REF_DIR);
dir = &entry->u.subdir;
if (entry->flag & REF_INCOMPLETE) {
read_loose_refs(entry->name, dir);
entry->flag &= ~REF_INCOMPLETE;
}
return dir;
}

static struct ref_entry *create_ref_entry(const char *refname,
const unsigned char *sha1, int flag,
int check_name)
{
int len;
struct ref_entry *ref;

if (check_name &&
check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
die("Reference has invalid format: '%s'", refname);
len = strlen(refname) + 1;
ref = xmalloc(sizeof(struct ref_entry) + len);
hashcpy(ref->u.value.sha1, sha1);
hashclr(ref->u.value.peeled);
memcpy(ref->name, refname, len);
ref->flag = flag;
return ref;
}

static void clear_ref_dir(struct ref_dir *dir);

static void free_ref_entry(struct ref_entry *entry)
{
if (entry->flag & REF_DIR) {
/*
* Do not use get_ref_dir() here, as that might
* trigger the reading of loose refs.
*/
clear_ref_dir(&entry->u.subdir);
}
free(entry);
}

/*
* Add a ref_entry to the end of dir (unsorted). Entry is always
* stored directly in dir; no recursion into subdirectories is
* done.
*/
static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry)
{
ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc);
dir->entries[dir->nr++] = entry;
/* optimize for the case that entries are added in order */
if (dir->nr == 1 ||
(dir->nr == dir->sorted + 1 &&
strcmp(dir->entries[dir->nr - 2]->name,
dir->entries[dir->nr - 1]->name) < 0))
dir->sorted = dir->nr;
}

/*
* Clear and free all entries in dir, recursively.
*/
static void clear_ref_dir(struct ref_dir *dir)
{
int i;
for (i = 0; i < dir->nr; i++)
free_ref_entry(dir->entries[i]);
free(dir->entries);
dir->sorted = dir->nr = dir->alloc = 0;
dir->entries = NULL;
}

/*
* Create a struct ref_entry object for the specified dirname.
* dirname is the name of the directory with a trailing slash (e.g.,
* "refs/heads/") or "" for the top-level directory.
*/
static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache,
const char *dirname, size_t len,
int incomplete)
{
struct ref_entry *direntry;
direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1);
memcpy(direntry->name, dirname, len);
direntry->name[len] = '\0';
direntry->u.subdir.ref_cache = ref_cache;
direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0);
return direntry;
}

static int ref_entry_cmp(const void *a, const void *b)
{
struct ref_entry *one = *(struct ref_entry **)a;
struct ref_entry *two = *(struct ref_entry **)b;
return strcmp(one->name, two->name);
}

static void sort_ref_dir(struct ref_dir *dir);

struct string_slice {
size_t len;
const char *str;
};

static int ref_entry_cmp_sslice(const void *key_, const void *ent_)
{
struct string_slice *key = (struct string_slice *)key_;
struct ref_entry *ent = *(struct ref_entry **)ent_;
int entlen = strlen(ent->name);
int cmplen = key->len < entlen ? key->len : entlen;
int cmp = memcmp(key->str, ent->name, cmplen);
if (cmp)
return cmp;
return key->len - entlen;
}

/*
* Return the entry with the given refname from the ref_dir
* (non-recursively), sorting dir if necessary. Return NULL if no
* such entry is found. dir must already be complete.
*/
static struct ref_entry *search_ref_dir(struct ref_dir *dir,
const char *refname, size_t len)
{
struct ref_entry **r;
struct string_slice key;

if (refname == NULL || !dir->nr)
return NULL;

sort_ref_dir(dir);
key.len = len;
key.str = refname;
r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries),
ref_entry_cmp_sslice);

if (r == NULL)
return NULL;

return *r;
}

/*
* Search for a directory entry directly within dir (without
* recursing). Sort dir if necessary. subdirname must be a directory
* name (i.e., end in '/'). If mkdir is set, then create the
* directory if it is missing; otherwise, return NULL if the desired
* directory cannot be found. dir must already be complete.
*/
static struct ref_dir *search_for_subdir(struct ref_dir *dir,
const char *subdirname, size_t len,
int mkdir)
{
struct ref_entry *entry = search_ref_dir(dir, subdirname, len);
if (!entry) {
if (!mkdir)
return NULL;
/*
* Since dir is complete, the absence of a subdir
* means that the subdir really doesn't exist;
* therefore, create an empty record for it but mark
* the record complete.
*/
entry = create_dir_entry(dir->ref_cache, subdirname, len, 0);
add_entry_to_dir(dir, entry);
}
return get_ref_dir(entry);
}

/*
* If refname is a reference name, find the ref_dir within the dir
* tree that should hold refname. If refname is a directory name
* (i.e., ends in '/'), then return that ref_dir itself. dir must
* represent the top-level directory and must already be complete.
* Sort ref_dirs and recurse into subdirectories as necessary. If
* mkdir is set, then create any missing directories; otherwise,
* return NULL if the desired directory cannot be found.
*/
static struct ref_dir *find_containing_dir(struct ref_dir *dir,
const char *refname, int mkdir)
{
const char *slash;
for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
size_t dirnamelen = slash - refname + 1;
struct ref_dir *subdir;
subdir = search_for_subdir(dir, refname, dirnamelen, mkdir);
if (!subdir) {
dir = NULL;
break;
}
dir = subdir;
}

return dir;
}

/*
* Find the value entry with the given name in dir, sorting ref_dirs
* and recursing into subdirectories as necessary. If the name is not
* found or it corresponds to a directory entry, return NULL.
*/
static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname)
{
struct ref_entry *entry;
dir = find_containing_dir(dir, refname, 0);
if (!dir)
return NULL;
entry = search_ref_dir(dir, refname, strlen(refname));
return (entry && !(entry->flag & REF_DIR)) ? entry : NULL;
}

/*
* Add a ref_entry to the ref_dir (unsorted), recursing into
* subdirectories as necessary. dir must represent the top-level
* directory. Return 0 on success.
*/
static int add_ref(struct ref_dir *dir, struct ref_entry *ref)
{
dir = find_containing_dir(dir, ref->name, 1);
if (!dir)
return -1;
add_entry_to_dir(dir, ref);
return 0;
}

/*
* Emit a warning and return true iff ref1 and ref2 have the same name
* and the same sha1. Die if they have the same name but different
* sha1s.
*/
static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
{
if (strcmp(ref1->name, ref2->name))
return 0;

/* Duplicate name; make sure that they don't conflict: */

if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR))
/* This is impossible by construction */
die("Reference directory conflict: %s", ref1->name);

if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1))
die("Duplicated ref, and SHA1s don't match: %s", ref1->name);

warning("Duplicated ref: %s", ref1->name);
return 1;
}

/*
* Sort the entries in dir non-recursively (if they are not already
* sorted) and remove any duplicate entries.
*/
static void sort_ref_dir(struct ref_dir *dir)
{
int i, j;
struct ref_entry *last = NULL;

/*
* This check also prevents passing a zero-length array to qsort(),
* which is a problem on some platforms.
*/
if (dir->sorted == dir->nr)
return;

qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp);

/* Remove any duplicates: */
for (i = 0, j = 0; j < dir->nr; j++) {
struct ref_entry *entry = dir->entries[j];
if (last && is_dup_ref(last, entry))
free_ref_entry(entry);
else
last = dir->entries[i++] = entry;
}
dir->sorted = dir->nr = i;
}

#define DO_FOR_EACH_INCLUDE_BROKEN 01

static struct ref_entry *current_ref;

static int do_one_ref(const char *base, each_ref_fn fn, int trim,
int flags, void *cb_data, struct ref_entry *entry)
{
int retval;
if (prefixcmp(entry->name, base))
return 0;

if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
if (entry->flag & REF_ISBROKEN)
return 0; /* ignore broken refs e.g. dangling symref */
if (!has_sha1_file(entry->u.value.sha1)) {
error("%s does not point to a valid object!", entry->name);
return 0;
}
}
current_ref = entry;
retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data);
current_ref = NULL;
return retval;
}

/*
* Call fn for each reference in dir that has index in the range
* offset <= index < dir->nr. Recurse into subdirectories that are in
* that index range, sorting them before iterating. This function
* does not sort dir itself; it should be sorted beforehand.
*/
static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset,
const char *base,
each_ref_fn fn, int trim, int flags, void *cb_data)
{
int i;
assert(dir->sorted == dir->nr);
for (i = offset; i < dir->nr; i++) {
struct ref_entry *entry = dir->entries[i];
int retval;
if (entry->flag & REF_DIR) {
struct ref_dir *subdir = get_ref_dir(entry);
sort_ref_dir(subdir);
retval = do_for_each_ref_in_dir(subdir, 0,
base, fn, trim, flags, cb_data);
} else {
retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
}
if (retval)
return retval;
}
return 0;
}

/*
* Call fn for each reference in the union of dir1 and dir2, in order
* by refname. Recurse into subdirectories. If a value entry appears
* in both dir1 and dir2, then only process the version that is in
* dir2. The input dirs must already be sorted, but subdirs will be
* sorted as needed.
*/
static int do_for_each_ref_in_dirs(struct ref_dir *dir1,
struct ref_dir *dir2,
const char *base, each_ref_fn fn, int trim,
int flags, void *cb_data)
{
int retval;
int i1 = 0, i2 = 0;

assert(dir1->sorted == dir1->nr);
assert(dir2->sorted == dir2->nr);
while (1) {
struct ref_entry *e1, *e2;
int cmp;
if (i1 == dir1->nr) {
return do_for_each_ref_in_dir(dir2, i2,
base, fn, trim, flags, cb_data);
}
if (i2 == dir2->nr) {
return do_for_each_ref_in_dir(dir1, i1,
base, fn, trim, flags, cb_data);
}
e1 = dir1->entries[i1];
e2 = dir2->entries[i2];
cmp = strcmp(e1->name, e2->name);
if (cmp == 0) {
if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
/* Both are directories; descend them in parallel. */
struct ref_dir *subdir1 = get_ref_dir(e1);
struct ref_dir *subdir2 = get_ref_dir(e2);
sort_ref_dir(subdir1);
sort_ref_dir(subdir2);
retval = do_for_each_ref_in_dirs(
subdir1, subdir2,
base, fn, trim, flags, cb_data);
i1++;
i2++;
} else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
/* Both are references; ignore the one from dir1. */
retval = do_one_ref(base, fn, trim, flags, cb_data, e2);
i1++;
i2++;
} else {
die("conflict between reference and directory: %s",
e1->name);
}
} else {
struct ref_entry *e;
if (cmp < 0) {
e = e1;
i1++;
} else {
e = e2;
i2++;
}
if (e->flag & REF_DIR) {
struct ref_dir *subdir = get_ref_dir(e);
sort_ref_dir(subdir);
retval = do_for_each_ref_in_dir(
subdir, 0,
base, fn, trim, flags, cb_data);
} else {
retval = do_one_ref(base, fn, trim, flags, cb_data, e);
}
}
if (retval)
return retval;
}
if (i1 < dir1->nr)
return do_for_each_ref_in_dir(dir1, i1,
base, fn, trim, flags, cb_data);
if (i2 < dir2->nr)
return do_for_each_ref_in_dir(dir2, i2,
base, fn, trim, flags, cb_data);
return 0;
}

/*
* Return true iff refname1 and refname2 conflict with each other.
* Two reference names conflict if one of them exactly matches the
* leading components of the other; e.g., "foo/bar" conflicts with
* both "foo" and with "foo/bar/baz" but not with "foo/bar" or
* "foo/barbados".
*/
static int names_conflict(const char *refname1, const char *refname2)
{
for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
;
return (*refname1 == '\0' && *refname2 == '/')
|| (*refname1 == '/' && *refname2 == '\0');
}

struct name_conflict_cb {
const char *refname;
const char *oldrefname;
const char *conflicting_refname;
};

static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
int flags, void *cb_data)
{
struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
return 0;
if (names_conflict(data->refname, existingrefname)) {
data->conflicting_refname = existingrefname;
return 1;
}
return 0;
}

/*
* Return true iff a reference named refname could be created without
* conflicting with the name of an existing reference in array. If
* oldrefname is non-NULL, ignore potential conflicts with oldrefname
* (e.g., because oldrefname is scheduled for deletion in the same
* operation).
*/
static int is_refname_available(const char *refname, const char *oldrefname,
struct ref_dir *dir)
{
struct name_conflict_cb data;
data.refname = refname;
data.oldrefname = oldrefname;
data.conflicting_refname = NULL;

sort_ref_dir(dir);
if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn,
0, DO_FOR_EACH_INCLUDE_BROKEN,
&data)) {
error("'%s' exists; cannot create '%s'",
data.conflicting_refname, refname);
return 0;
}
return 1;
}

/*
* Future: need to be in "struct repository"
* when doing a full libification.
*/
static struct ref_cache {
struct ref_cache *next;
struct ref_entry *loose;
struct ref_entry *packed;
/* The submodule name, or "" for the main repo. */
char name[FLEX_ARRAY];
} *ref_cache;

static void clear_packed_ref_cache(struct ref_cache *refs)
{
if (refs->packed) {
free_ref_entry(refs->packed);
refs->packed = NULL;
}
}

static void clear_loose_ref_cache(struct ref_cache *refs)
{
if (refs->loose) {
free_ref_entry(refs->loose);
refs->loose = NULL;
}
}

static struct ref_cache *create_ref_cache(const char *submodule)
{
int len;
struct ref_cache *refs;
if (!submodule)
submodule = "";
len = strlen(submodule) + 1;
refs = xcalloc(1, sizeof(struct ref_cache) + len);
memcpy(refs->name, submodule, len);
return refs;
}

/*
* Return a pointer to a ref_cache for the specified submodule. For
* the main repository, use submodule==NULL. The returned structure
* will be allocated and initialized but not necessarily populated; it
* should not be freed.
*/
static struct ref_cache *get_ref_cache(const char *submodule)
{
struct ref_cache *refs = ref_cache;
if (!submodule)
submodule = "";
while (refs) {
if (!strcmp(submodule, refs->name))
return refs;
refs = refs->next;
}

refs = create_ref_cache(submodule);
refs->next = ref_cache;
ref_cache = refs;
return refs;
}

void invalidate_ref_cache(const char *submodule)
{
struct ref_cache *refs = get_ref_cache(submodule);
clear_packed_ref_cache(refs);
clear_loose_ref_cache(refs);
}

/*
* Parse one line from a packed-refs file. Write the SHA1 to sha1.
* Return a pointer to the refname within the line (null-terminated),
* or NULL if there was a problem.
*/
static const char *parse_ref_line(char *line, unsigned char *sha1)
{
/*
* 42: the answer to everything.
*
* In this case, it happens to be the answer to
* 40 (length of sha1 hex representation)
* +1 (space in between hex and name)
* +1 (newline at the end of the line)
*/
int len = strlen(line) - 42;

if (len <= 0)
return NULL;
if (get_sha1_hex(line, sha1) < 0)
return NULL;
if (!isspace(line[40]))
return NULL;
line += 41;
if (isspace(*line))
return NULL;
if (line[len] != '\n')
return NULL;
line[len] = 0;

return line;
}

static void read_packed_refs(FILE *f, struct ref_dir *dir)
{
struct ref_entry *last = NULL;
char refline[PATH_MAX];
int flag = REF_ISPACKED;

while (fgets(refline, sizeof(refline), f)) {
unsigned char sha1[20];
const char *refname;
static const char header[] = "# pack-refs with:";

if (!strncmp(refline, header, sizeof(header)-1)) {
const char *traits = refline + sizeof(header) - 1;
if (strstr(traits, " peeled "))
flag |= REF_KNOWS_PEELED;
/* perhaps other traits later as well */
continue;
}

refname = parse_ref_line(refline, sha1);
if (refname) {
last = create_ref_entry(refname, sha1, flag, 1);
add_ref(dir, last);
continue;
}
if (last &&
refline[0] == '^' &&
strlen(refline) == 42 &&
refline[41] == '\n' &&
!get_sha1_hex(refline + 1, sha1))
hashcpy(last->u.value.peeled, sha1);
}
}

static struct ref_dir *get_packed_refs(struct ref_cache *refs)
{
if (!refs->packed) {
const char *packed_refs_file;
FILE *f;

refs->packed = create_dir_entry(refs, "", 0, 0);
if (*refs->name)
packed_refs_file = git_path_submodule(refs->name, "packed-refs");
else
packed_refs_file = git_path("packed-refs");
f = fopen(packed_refs_file, "r");
if (f) {
read_packed_refs(f, get_ref_dir(refs->packed));
fclose(f);
}
}
return get_ref_dir(refs->packed);
}

void add_packed_ref(const char *refname, const unsigned char *sha1)
{
add_ref(get_packed_refs(get_ref_cache(NULL)),
create_ref_entry(refname, sha1, REF_ISPACKED, 1));
}

/*
* Read the loose references from the namespace dirname into dir
* (without recursing). dirname must end with '/'. dir must be the
* directory entry corresponding to dirname.
*/
static void read_loose_refs(const char *dirname, struct ref_dir *dir)
{
struct ref_cache *refs = dir->ref_cache;
DIR *d;
const char *path;
struct dirent *de;
int dirnamelen = strlen(dirname);
struct strbuf refname;

if (*refs->name)
path = git_path_submodule(refs->name, "%s", dirname);
else
path = git_path("%s", dirname);

d = opendir(path);
if (!d)
return;

strbuf_init(&refname, dirnamelen + 257);
strbuf_add(&refname, dirname, dirnamelen);

while ((de = readdir(d)) != NULL) {
unsigned char sha1[20];
struct stat st;
int flag;
const char *refdir;

if (de->d_name[0] == '.')
continue;
if (has_extension(de->d_name, ".lock"))
continue;
strbuf_addstr(&refname, de->d_name);
refdir = *refs->name
? git_path_submodule(refs->name, "%s", refname.buf)
: git_path("%s", refname.buf);
if (stat(refdir, &st) < 0) {
; /* silently ignore */
} else if (S_ISDIR(st.st_mode)) {
strbuf_addch(&refname, '/');
add_entry_to_dir(dir,
create_dir_entry(refs, refname.buf,
refname.len, 1));
} else {
if (*refs->name) {
hashclr(sha1);
flag = 0;
if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
hashclr(sha1);
flag |= REF_ISBROKEN;
}
} else if (read_ref_full(refname.buf, sha1, 1, &flag)) {
hashclr(sha1);
flag |= REF_ISBROKEN;
}
add_entry_to_dir(dir,
create_ref_entry(refname.buf, sha1, flag, 1));
}
strbuf_setlen(&refname, dirnamelen);
}
strbuf_release(&refname);
closedir(d);
}

static struct ref_dir *get_loose_refs(struct ref_cache *refs)
{
if (!refs->loose) {
/*
* Mark the top-level directory complete because we
* are about to read the only subdirectory that can
* hold references:
*/
refs->loose = create_dir_entry(refs, "", 0, 0);
/*
* Create an incomplete entry for "refs/":
*/
add_entry_to_dir(get_ref_dir(refs->loose),
create_dir_entry(refs, "refs/", 5, 1));
}
return get_ref_dir(refs->loose);
}

/* We allow "recursive" symbolic refs. Only within reason, though */
#define MAXDEPTH 5
#define MAXREFLEN (1024)

/*
* Called by resolve_gitlink_ref_recursive() after it failed to read
* from the loose refs in ref_cache refs. Find <refname> in the
* packed-refs file for the submodule.
*/
static int resolve_gitlink_packed_ref(struct ref_cache *refs,
const char *refname, unsigned char *sha1)
{
struct ref_entry *ref;
struct ref_dir *dir = get_packed_refs(refs);

ref = find_ref(dir, refname);
if (ref == NULL)
return -1;

memcpy(sha1, ref->u.value.sha1, 20);
return 0;
}

static int resolve_gitlink_ref_recursive(struct ref_cache *refs,
const char *refname, unsigned char *sha1,
int recursion)
{
int fd, len;
char buffer[128], *p;
char *path;

if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)
return -1;
path = *refs->name
? git_path_submodule(refs->name, "%s", refname)
: git_path("%s", refname);
fd = open(path, O_RDONLY);
if (fd < 0)
return resolve_gitlink_packed_ref(refs, refname, sha1);

len = read(fd, buffer, sizeof(buffer)-1);
close(fd);
if (len < 0)
return -1;
while (len && isspace(buffer[len-1]))
len--;
buffer[len] = 0;

/* Was it a detached head or an old-fashioned symlink? */
if (!get_sha1_hex(buffer, sha1))
return 0;

/* Symref? */
if (strncmp(buffer, "ref:", 4))
return -1;
p = buffer + 4;
while (isspace(*p))
p++;

return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);
}

int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)
{
int len = strlen(path), retval;
char *submodule;
struct ref_cache *refs;

while (len && path[len-1] == '/')
len--;
if (!len)
return -1;
submodule = xstrndup(path, len);
refs = get_ref_cache(submodule);
free(submodule);

retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
return retval;
}

/*
* Try to read ref from the packed references. On success, set sha1
* and return 0; otherwise, return -1.
*/
static int get_packed_ref(const char *refname, unsigned char *sha1)
{
struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
struct ref_entry *entry = find_ref(packed, refname);
if (entry) {
hashcpy(sha1, entry->u.value.sha1);
return 0;
}
return -1;
}

const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
{
int depth = MAXDEPTH;
ssize_t len;
char buffer[256];
static char refname_buffer[256];

if (flag)
*flag = 0;

if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
return NULL;

for (;;) {
char path[PATH_MAX];
struct stat st;
char *buf;
int fd;

if (--depth < 0)
return NULL;

git_snpath(path, sizeof(path), "%s", refname);

if (lstat(path, &st) < 0) {
if (errno != ENOENT)
return NULL;
/*
* The loose reference file does not exist;
* check for a packed reference.
*/
if (!get_packed_ref(refname, sha1)) {
if (flag)
*flag |= REF_ISPACKED;
return refname;
}
/* The reference is not a packed reference, either. */
if (reading) {
return NULL;
} else {
hashclr(sha1);
return refname;
}
}

/* Follow "normalized" - ie "refs/.." symlinks by hand */
if (S_ISLNK(st.st_mode)) {
len = readlink(path, buffer, sizeof(buffer)-1);
if (len < 0)
return NULL;
buffer[len] = 0;
if (!prefixcmp(buffer, "refs/") &&
!check_refname_format(buffer, 0)) {
strcpy(refname_buffer, buffer);
refname = refname_buffer;
if (flag)
*flag |= REF_ISSYMREF;
continue;
}
}

/* Is it a directory? */
if (S_ISDIR(st.st_mode)) {
errno = EISDIR;
return NULL;
}

/*
* Anything else, just open it and try to use it as
* a ref
*/
fd = open(path, O_RDONLY);
if (fd < 0)
return NULL;
len = read_in_full(fd, buffer, sizeof(buffer)-1);
close(fd);
if (len < 0)
return NULL;
while (len && isspace(buffer[len-1]))
len--;
buffer[len] = '\0';

/*
* Is it a symbolic ref?
*/
if (prefixcmp(buffer, "ref:"))
break;
if (flag)
*flag |= REF_ISSYMREF;
buf = buffer + 4;
while (isspace(*buf))
buf++;
if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
if (flag)
*flag |= REF_ISBROKEN;
return NULL;
}
refname = strcpy(refname_buffer, buf);
}
/* Please note that FETCH_HEAD has a second line containing other data. */
if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {
if (flag)
*flag |= REF_ISBROKEN;
return NULL;
}
return refname;
}

char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
{
const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);
return ret ? xstrdup(ret) : NULL;
}

/* 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, unsigned char *sha1, int reading, int *flags)
{
if (resolve_ref_unsafe(refname, sha1, reading, flags))
return 0;
return -1;
}

int read_ref(const char *refname, unsigned char *sha1)
{
return read_ref_full(refname, sha1, 1, NULL);
}

int ref_exists(const char *refname)
{
unsigned char sha1[20];
return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
}

static int filter_refs(const char *refname, const unsigned char *sha1, int flags,
void *data)
{
struct ref_filter *filter = (struct ref_filter *)data;
if (fnmatch(filter->pattern, refname, 0))
return 0;
return filter->fn(refname, sha1, flags, filter->cb_data);
}

int peel_ref(const char *refname, unsigned char *sha1)
{
int flag;
unsigned char base[20];
struct object *o;

if (current_ref && (current_ref->name == refname
|| !strcmp(current_ref->name, refname))) {
if (current_ref->flag & REF_KNOWS_PEELED) {
hashcpy(sha1, current_ref->u.value.peeled);
return 0;
}
hashcpy(base, current_ref->u.value.sha1);
goto fallback;
}

if (read_ref_full(refname, base, 1, &flag))
return -1;

if ((flag & REF_ISPACKED)) {
struct ref_dir *dir = get_packed_refs(get_ref_cache(NULL));
struct ref_entry *r = find_ref(dir, refname);

if (r != NULL && r->flag & REF_KNOWS_PEELED) {
hashcpy(sha1, r->u.value.peeled);
return 0;
}
}

fallback:
o = parse_object(base);
if (o && o->type == OBJ_TAG) {
o = deref_tag(o, refname, 0);
if (o) {
hashcpy(sha1, o->sha1);
return 0;
}
}
return -1;
}

struct warn_if_dangling_data {
FILE *fp;
const char *refname;
const char *msg_fmt;
};

static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
int flags, void *cb_data)
{
struct warn_if_dangling_data *d = cb_data;
const char *resolves_to;
unsigned char junk[20];

if (!(flags & REF_ISSYMREF))
return 0;

resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
if (!resolves_to || strcmp(resolves_to, d->refname))
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.msg_fmt = msg_fmt;
for_each_rawref(warn_if_dangling_symref, &data);
}

static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,
int trim, int flags, void *cb_data)
{
struct ref_cache *refs = get_ref_cache(submodule);
struct ref_dir *packed_dir = get_packed_refs(refs);
struct ref_dir *loose_dir = get_loose_refs(refs);
int retval = 0;

if (base && *base) {
packed_dir = find_containing_dir(packed_dir, base, 0);
loose_dir = find_containing_dir(loose_dir, base, 0);
}

if (packed_dir && loose_dir) {
sort_ref_dir(packed_dir);
sort_ref_dir(loose_dir);
retval = do_for_each_ref_in_dirs(
packed_dir, loose_dir,
base, fn, trim, flags, cb_data);
} else if (packed_dir) {
sort_ref_dir(packed_dir);
retval = do_for_each_ref_in_dir(
packed_dir, 0,
base, fn, trim, flags, cb_data);
} else if (loose_dir) {
sort_ref_dir(loose_dir);
retval = do_for_each_ref_in_dir(
loose_dir, 0,
base, fn, trim, flags, cb_data);
}

return retval;
}

static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
{
unsigned char sha1[20];
int flag;

if (submodule) {
if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)
return fn("HEAD", sha1, 0, cb_data);

return 0;
}

if (!read_ref_full("HEAD", sha1, 1, &flag))
return fn("HEAD", sha1, flag, cb_data);

return 0;
}

int head_ref(each_ref_fn fn, void *cb_data)
{
return do_head_ref(NULL, fn, cb_data);
}

int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
{
return do_head_ref(submodule, 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_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_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 for_each_replace_ref(each_ref_fn fn, void *cb_data)
{
return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
}

int head_ref_namespaced(each_ref_fn fn, void *cb_data)
{
struct strbuf buf = STRBUF_INIT;
int ret = 0;
unsigned char sha1[20];
int flag;

strbuf_addf(&buf, "%sHEAD", get_git_namespace());
if (!read_ref_full(buf.buf, sha1, 1, &flag))
ret = fn(buf.buf, sha1, flag, cb_data);
strbuf_release(&buf);

return ret;
}

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_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 && prefixcmp(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. */
if (real_pattern.buf[real_pattern.len - 1] != '/')
strbuf_addch(&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);
}

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);
}

const char *prettify_refname(const char *name)
{
return name + (
!prefixcmp(name, "refs/heads/") ? 11 :
!prefixcmp(name, "refs/tags/") ? 10 :
!prefixcmp(name, "refs/remotes/") ? 13 :
0);
}

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 **rules)
{
const char **p;
const int abbrev_name_len = strlen(abbrev_name);

for (p = rules; *p; p++) {
if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
return 1;
}
}

return 0;
}

static struct ref_lock *verify_lock(struct ref_lock *lock,
const unsigned char *old_sha1, int mustexist)
{
if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
error("Can't verify ref %s", lock->ref_name);
unlock_ref(lock);
return NULL;
}
if (hashcmp(lock->old_sha1, old_sha1)) {
error("Ref %s is at %s but expected %s", lock->ref_name,
sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
unlock_ref(lock);
return NULL;
}
return lock;
}

static int remove_empty_directories(const char *file)
{
/* we want to create a file but there is a directory there;
* if that is an empty directory (or a directory that contains
* only empty directories), remove them.
*/
struct strbuf path;
int result;

strbuf_init(&path, 20);
strbuf_addstr(&path, file);

result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);

strbuf_release(&path);

return result;
}

/*
* *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, &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, this_result, 1, &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++) {
struct stat st;
unsigned char hash[20];
char path[PATH_MAX];
const char *ref, *it;

mksnpath(path, sizeof(path), *p, len, str);
ref = resolve_ref_unsafe(path, hash, 1, NULL);
if (!ref)
continue;
if (!stat(git_path("logs/%s", path), &st) &&
S_ISREG(st.st_mode))
it = path;
else if (strcmp(ref, path) &&
!stat(git_path("logs/%s", ref), &st) &&
S_ISREG(st.st_mode))
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 struct ref_lock *lock_ref_sha1_basic(const char *refname,
const unsigned char *old_sha1,
int flags, int *type_p)
{
char *ref_file;
const char *orig_refname = refname;
struct ref_lock *lock;
int last_errno = 0;
int type, lflags;
int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
int missing = 0;

lock = xcalloc(1, sizeof(struct ref_lock));
lock->lock_fd = -1;

refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);
if (!refname && errno == EISDIR) {
/* we are trying to lock foo but we used to
* have foo/bar which now does not exist;
* it is normal for the empty directory 'foo'
* to remain.
*/
ref_file = git_path("%s", orig_refname);
if (remove_empty_directories(ref_file)) {
last_errno = errno;
error("there are still refs under '%s'", orig_refname);
goto error_return;
}
refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);
}
if (type_p)
*type_p = type;
if (!refname) {
last_errno = errno;
error("unable to resolve reference %s: %s",
orig_refname, strerror(errno));
goto error_return;
}
missing = is_null_sha1(lock->old_sha1);
/* When the ref did not exist and we are creating it,
* make sure there is no existing ref that is packed
* whose name begins with our refname, nor a ref whose
* name is a proper prefix of our refname.
*/
if (missing &&
!is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {
last_errno = ENOTDIR;
goto error_return;
}

lock->lk = xcalloc(1, sizeof(struct lock_file));

lflags = LOCK_DIE_ON_ERROR;
if (flags & REF_NODEREF) {
refname = orig_refname;
lflags |= LOCK_NODEREF;
}
lock->ref_name = xstrdup(refname);
lock->orig_ref_name = xstrdup(orig_refname);
ref_file = git_path("%s", refname);
if (missing)
lock->force_write = 1;
if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
lock->force_write = 1;

if (safe_create_leading_directories(ref_file)) {
last_errno = errno;
error("unable to create directory for %s", ref_file);
goto error_return;
}

lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;

 error_return:
unlock_ref(lock);
errno = last_errno;
return NULL;
}

struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
{
char refpath[PATH_MAX];
if (check_refname_format(refname, 0))
return NULL;
strcpy(refpath, mkpath("refs/%s", refname));
return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
}

struct ref_lock *lock_any_ref_for_update(const char *refname,
const unsigned char *old_sha1, int flags)
{
if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
return NULL;
return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
}

struct repack_without_ref_sb {
const char *refname;
int fd;
};

static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
int flags, void *cb_data)
{
struct repack_without_ref_sb *data = cb_data;
char line[PATH_MAX + 100];
int len;

if (!strcmp(data->refname, refname))
return 0;
len = snprintf(line, sizeof(line), "%s %s\n",
sha1_to_hex(sha1), refname);
/* this should not happen but just being defensive */
if (len > sizeof(line))
die("too long a refname '%s'", refname);
write_or_die(data->fd, line, len);
return 0;
}

static struct lock_file packlock;

static int repack_without_ref(const char *refname)
{
struct repack_without_ref_sb data;
struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));
if (find_ref(packed, refname) == NULL)
return 0;
data.refname = refname;
data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
if (data.fd < 0) {
unable_to_lock_error(git_path("packed-refs"), errno);
return error("cannot delete '%s' from packed refs", refname);
}
do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
return commit_lock_file(&packlock);
}

int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
{
struct ref_lock *lock;
int err, i = 0, ret = 0, flag = 0;

lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
if (!lock)
return 1;
if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
/* loose */
const char *path;

if (!(delopt & REF_NODEREF)) {
i = strlen(lock->lk->filename) - 5; /* .lock */
lock->lk->filename[i] = 0;
path = lock->lk->filename;
} else {
path = git_path("%s", refname);
}
err = unlink_or_warn(path);
if (err && errno != ENOENT)
ret = 1;

if (!(delopt & REF_NODEREF))
lock->lk->filename[i] = '.';
}
/* removing the loose one could have resurrected an earlier
* packed one. Also, if it was not loose we need to repack
* without it.
*/
ret |= repack_without_ref(refname);

unlink_or_warn(git_path("logs/%s", lock->ref_name));
invalidate_ref_cache(NULL);
unlock_ref(lock);
return ret;
}

/*
* People using contrib's git-new-workdir have .git/logs/refs ->
* /some/other/path/.git/logs/refs, and that may live on another device.
*
* IOW, to avoid cross device rename errors, the temporary renamed log must
* live into logs/refs.
*/
#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"

int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
{
unsigned char sha1[20], orig_sha1[20];
int flag = 0, logmoved = 0;
struct ref_lock *lock;
struct stat loginfo;
int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
const char *symref = NULL;
struct ref_cache *refs = get_ref_cache(NULL);

if (log && S_ISLNK(loginfo.st_mode))
return error("reflog for %s is a symlink", oldrefname);

symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);
if (flag & REF_ISSYMREF)
return error("refname %s is a symbolic ref, renaming it is not supported",
oldrefname);
if (!symref)
return error("refname %s not found", oldrefname);

if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))
return 1;

if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))
return 1;

if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",
oldrefname, strerror(errno));

if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {
error("unable to delete old %s", oldrefname);
goto rollback;
}

if (!read_ref_full(newrefname, sha1, 1, &flag) &&
delete_ref(newrefname, sha1, REF_NODEREF)) {
if (errno==EISDIR) {
if (remove_empty_directories(git_path("%s", newrefname))) {
error("Directory not empty: %s", newrefname);
goto rollback;
}
} else {
error("unable to delete existing %s", newrefname);
goto rollback;
}
}

if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {
error("unable to create directory for %s", newrefname);
goto rollback;
}

 retry:
if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {
if (errno==EISDIR || errno==ENOTDIR) {
/*
* rename(a, b) when b is an existing
* directory ought to result in ISDIR, but
* Solaris 5.8 gives ENOTDIR. Sheesh.
*/
if (remove_empty_directories(git_path("logs/%s", newrefname))) {
error("Directory not empty: logs/%s", newrefname);
goto rollback;
}
goto retry;
} else {
error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",
newrefname, strerror(errno));
goto rollback;
}
}
logmoved = log;

lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
if (!lock) {
error("unable to lock %s for update", newrefname);
goto rollback;
}
lock->force_write = 1;
hashcpy(lock->old_sha1, orig_sha1);
if (write_ref_sha1(lock, orig_sha1, logmsg)) {
error("unable to write current sha1 into %s", newrefname);
goto rollback;
}

return 0;

 rollback:
lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
if (!lock) {
error("unable to lock %s for rollback", oldrefname);
goto rollbacklog;
}

lock->force_write = 1;
flag = log_all_ref_updates;
log_all_ref_updates = 0;
if (write_ref_sha1(lock, orig_sha1, NULL))
error("unable to write current sha1 into %s", oldrefname);
log_all_ref_updates = flag;

 rollbacklog:
if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))
error("unable to restore logfile %s from %s: %s",
oldrefname, newrefname, strerror(errno));
if (!logmoved && log &&
rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))
error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",
oldrefname, strerror(errno));

return 1;
}

int close_ref(struct ref_lock *lock)
{
if (close_lock_file(lock->lk))
return -1;
lock->lock_fd = -1;
return 0;
}

int commit_ref(struct ref_lock *lock)
{
if (commit_lock_file(lock->lk))
return -1;
lock->lock_fd = -1;
return 0;
}

void unlock_ref(struct ref_lock *lock)
{
/* Do not free lock->lk -- atexit() still looks at them */
if (lock->lk)
rollback_lock_file(lock->lk);
free(lock->ref_name);
free(lock->orig_ref_name);
free(lock);
}

/*
* copy the reflog message msg to buf, which has been allocated sufficiently
* large, while cleaning up the whitespaces. Especially, convert LF to space,
* because reflog file is one line per entry.
*/
static int copy_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 log_ref_setup(const char *refname, char *logfile, int bufsize)
{
int logfd, oflags = O_APPEND | O_WRONLY;

git_snpath(logfile, bufsize, "logs/%s", refname);
if (log_all_ref_updates &&
(!prefixcmp(refname, "refs/heads/") ||
!prefixcmp(refname, "refs/remotes/") ||
!prefixcmp(refname, "refs/notes/") ||
!strcmp(refname, "HEAD"))) {
if (safe_create_leading_directories(logfile) < 0)
return error("unable to create directory for %s",
logfile);
oflags |= O_CREAT;
}

logfd = open(logfile, oflags, 0666);
if (logfd < 0) {
if (!(oflags & O_CREAT) && errno == ENOENT)
return 0;

if ((oflags & O_CREAT) && errno == EISDIR) {
if (remove_empty_directories(logfile)) {
return error("There are still logs under '%s'",
logfile);
}
logfd = open(logfile, oflags, 0666);
}

if (logfd < 0)
return error("Unable to append to %s: %s",
logfile, strerror(errno));
}

adjust_shared_perm(logfile);
close(logfd);
return 0;
}

static int log_ref_write(const char *refname, const unsigned char *old_sha1,
const unsigned char *new_sha1, const char *msg)
{
int logfd, result, written, oflags = O_APPEND | O_WRONLY;
unsigned maxlen, len;
int msglen;
char log_file[PATH_MAX];
char *logrec;
const char *committer;

if (log_all_ref_updates < 0)
log_all_ref_updates = !is_bare_repository();

result = log_ref_setup(refname, log_file, sizeof(log_file));
if (result)
return result;

logfd = open(log_file, oflags);
if (logfd < 0)
return 0;
msglen = msg ? strlen(msg) : 0;
committer = git_committer_info(0);
maxlen = strlen(committer) + msglen + 100;
logrec = xmalloc(maxlen);
len = sprintf(logrec, "%s %s %s\n",
sha1_to_hex(old_sha1),
sha1_to_hex(new_sha1),
committer);
if (msglen)
len += copy_msg(logrec + len - 1, msg) - 1;
written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
free(logrec);
if (close(logfd) != 0 || written != len)
return error("Unable to append to %s", log_file);
return 0;
}

static int is_branch(const char *refname)
{
return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
}

int write_ref_sha1(struct ref_lock *lock,
const unsigned char *sha1, const char *logmsg)
{
static char term = '\n';
struct object *o;

if (!lock)
return -1;
if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
unlock_ref(lock);
return 0;
}
o = parse_object(sha1);
if (!o) {
error("Trying to write ref %s with nonexistent object %s",
lock->ref_name, sha1_to_hex(sha1));
unlock_ref(lock);
return -1;
}
if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
error("Trying to write non-commit object %s to branch %s",
sha1_to_hex(sha1), lock->ref_name);
unlock_ref(lock);
return -1;
}
if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
write_in_full(lock->lock_fd, &term, 1) != 1
|| close_ref(lock) < 0) {
error("Couldn't write %s", lock->lk->filename);
unlock_ref(lock);
return -1;
}
clear_loose_ref_cache(get_ref_cache(NULL));
if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
(strcmp(lock->ref_name, lock->orig_ref_name) &&
log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
unlock_ref(lock);
return -1;
}
if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
/*
* Special hack: If a branch is updated directly and HEAD
* points to it (may happen on the remote side of a push
* for example) then logically the HEAD reflog should be
* updated too.
* A generic solution implies reverse symref information,
* but finding all symrefs pointing to the given branch
* would be rather costly for this rare event (the direct
* update of a branch) to be worth it. So let's cheat and
* check with HEAD only which should cover 99% of all usage
* scenarios (even 100% of the default ones).
*/
unsigned char head_sha1[20];
int head_flag;
const char *head_ref;
head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
if (head_ref && (head_flag & REF_ISSYMREF) &&
!strcmp(head_ref, lock->ref_name))
log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
}
if (commit_ref(lock)) {
error("Couldn't set %s", lock->ref_name);
unlock_ref(lock);
return -1;
}
unlock_ref(lock);
return 0;
}

int create_symref(const char *ref_target, const char *refs_heads_master,
const char *logmsg)
{
const char *lockpath;
char ref[1000];
int fd, len, written;
char *git_HEAD = git_pathdup("%s", ref_target);
unsigned char old_sha1[20], new_sha1[20];

if (logmsg && read_ref(ref_target, old_sha1))
hashclr(old_sha1);

if (safe_create_leading_directories(git_HEAD) < 0)
return error("unable to create directory for %s", git_HEAD);

#ifndef NO_SYMLINK_HEAD
if (prefer_symlink_refs) {
unlink(git_HEAD);
if (!symlink(refs_heads_master, git_HEAD))
goto done;
fprintf(stderr, "no symlink - falling back to symbolic ref\n");
}
#endif

len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
if (sizeof(ref) <= len) {
error("refname too long: %s", refs_heads_master);
goto error_free_return;
}
lockpath = mkpath("%s.lock", git_HEAD);
fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
if (fd < 0) {
error("Unable to open %s for writing", lockpath);
goto error_free_return;
}
written = write_in_full(fd, ref, len);
if (close(fd) != 0 || written != len) {
error("Unable to write to %s", lockpath);
goto error_unlink_return;
}
if (rename(lockpath, git_HEAD) < 0) {
error("Unable to create %s", git_HEAD);
goto error_unlink_return;
}
if (adjust_shared_perm(git_HEAD)) {
error("Unable to fix permissions on %s", lockpath);
error_unlink_return:
unlink_or_warn(lockpath);
error_free_return:
free(git_HEAD);
return -1;
}

#ifndef NO_SYMLINK_HEAD
done:
#endif
if (logmsg && !read_ref(refs_heads_master, new_sha1))
log_ref_write(ref_target, old_sha1, new_sha1, logmsg);

free(git_HEAD);
return 0;
}

static char *ref_msg(const char *line, const char *endp)
{
const char *ep;
line += 82;
ep = memchr(line, '\n', endp - line);
if (!ep)
ep = endp;
return xmemdupz(line, ep - line);
}

int read_ref_at(const char *refname, unsigned long at_time, int cnt,
unsigned char *sha1, char **msg,
unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
{
const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
char *tz_c;
int logfd, tz, reccnt = 0;
struct stat st;
unsigned long date;
unsigned char logged_sha1[20];
void *log_mapped;
size_t mapsz;

logfile = git_path("logs/%s", refname);
logfd = open(logfile, O_RDONLY, 0);
if (logfd < 0)
die_errno("Unable to read log '%s'", logfile);
fstat(logfd, &st);
if (!st.st_size)
die("Log %s is empty.", logfile);
mapsz = xsize_t(st.st_size);
log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
logdata = log_mapped;
close(logfd);

lastrec = NULL;
rec = logend = logdata + st.st_size;
while (logdata < rec) {
reccnt++;
if (logdata < rec && *(rec-1) == '\n')
rec--;
lastgt = NULL;
while (logdata < rec && *(rec-1) != '\n') {
rec--;
if (*rec == '>')
lastgt = rec;
}
if (!lastgt)
die("Log %s is corrupt.", logfile);
date = strtoul(lastgt + 1, &tz_c, 10);
if (date <= at_time || cnt == 0) {
tz = strtoul(tz_c, NULL, 10);
if (msg)
*msg = ref_msg(rec, logend);
if (cutoff_time)
*cutoff_time = date;
if (cutoff_tz)
*cutoff_tz = tz;
if (cutoff_cnt)
*cutoff_cnt = reccnt - 1;
if (lastrec) {
if (get_sha1_hex(lastrec, logged_sha1))
die("Log %s is corrupt.", logfile);
if (get_sha1_hex(rec + 41, sha1))
die("Log %s is corrupt.", logfile);
if (hashcmp(logged_sha1, sha1)) {
warning("Log %s has gap after %s.",
logfile, show_date(date, tz, DATE_RFC2822));
}
}
else if (date == at_time) {
if (get_sha1_hex(rec + 41, sha1))
die("Log %s is corrupt.", logfile);
}
else {
if (get_sha1_hex(rec + 41, logged_sha1))
die("Log %s is corrupt.", logfile);
if (hashcmp(logged_sha1, sha1)) {
warning("Log %s unexpectedly ended on %s.",
logfile, show_date(date, tz, DATE_RFC2822));
}
}
munmap(log_mapped, mapsz);
return 0;
}
lastrec = rec;
if (cnt > 0)
cnt--;
}

rec = logdata;
while (rec < logend && *rec != '>' && *rec != '\n')
rec++;
if (rec == logend || *rec == '\n')
die("Log %s is corrupt.", logfile);
date = strtoul(rec + 1, &tz_c, 10);
tz = strtoul(tz_c, NULL, 10);
if (get_sha1_hex(logdata, sha1))
die("Log %s is corrupt.", logfile);
if (is_null_sha1(sha1)) {
if (get_sha1_hex(logdata + 41, sha1))
die("Log %s is corrupt.", logfile);
}
if (msg)
*msg = ref_msg(logdata, logend);
munmap(log_mapped, mapsz);

if (cutoff_time)
*cutoff_time = date;
if (cutoff_tz)
*cutoff_tz = tz;
if (cutoff_cnt)
*cutoff_cnt = reccnt;
return 1;
}

int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)
{
const char *logfile;
FILE *logfp;
struct strbuf sb = STRBUF_INIT;
int ret = 0;

logfile = git_path("logs/%s", refname);
logfp = fopen(logfile, "r");
if (!logfp)
return -1;

if (ofs) {
struct stat statbuf;
if (fstat(fileno(logfp), &statbuf) ||
statbuf.st_size < ofs ||
fseek(logfp, -ofs, SEEK_END) ||
strbuf_getwholeline(&sb, logfp, '\n')) {
fclose(logfp);
strbuf_release(&sb);
return -1;
}
}

while (!strbuf_getwholeline(&sb, logfp, '\n')) {
unsigned char osha1[20], nsha1[20];
char *email_end, *message;
unsigned long timestamp;
int tz;

/* old SP new SP name <email> SP time TAB msg LF */
if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||
get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||
get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||
!(email_end = strchr(sb.buf + 82, '>')) ||
email_end[1] != ' ' ||
!(timestamp = strtoul(email_end + 2, &message, 10)) ||
!message || message[0] != ' ' ||
(message[1] != '+' && message[1] != '-') ||
!isdigit(message[2]) || !isdigit(message[3]) ||
!isdigit(message[4]) || !isdigit(message[5]))
continue; /* corrupt? */
email_end[1] = '\0';
tz = strtol(message + 1, NULL, 10);
if (message[6] != '\t')
message += 6;
else
message += 7;
ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,
cb_data);
if (ret)
break;
}
fclose(logfp);
strbuf_release(&sb);
return ret;
}

int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)
{
return for_each_recent_reflog_ent(refname, fn, 0, cb_data);
}

/*
* Call fn for each reflog in the namespace indicated by name. name
* must be empty or end with '/'. Name will be used as a scratch
* space, but its contents will be restored before return.
*/
static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
{
DIR *d = opendir(git_path("logs/%s", name->buf));
int retval = 0;
struct dirent *de;
int oldlen = name->len;

if (!d)
return name->len ? errno : 0;

while ((de = readdir(d)) != NULL) {
struct stat st;

if (de->d_name[0] == '.')
continue;
if (has_extension(de->d_name, ".lock"))
continue;
strbuf_addstr(name, de->d_name);
if (stat(git_path("logs/%s", name->buf), &st) < 0) {
; /* silently ignore */
} else {
if (S_ISDIR(st.st_mode)) {
strbuf_addch(name, '/');
retval = do_for_each_reflog(name, fn, cb_data);
} else {
unsigned char sha1[20];
if (read_ref_full(name->buf, sha1, 0, NULL))
retval = error("bad ref for %s", name->buf);
else
retval = fn(name->buf, sha1, 0, cb_data);
}
if (retval)
break;
}
strbuf_setlen(name, oldlen);
}
closedir(d);
return retval;
}

int for_each_reflog(each_ref_fn fn, void *cb_data)
{
int retval;
struct strbuf name;
strbuf_init(&name, PATH_MAX);
retval = do_for_each_reflog(&name, fn, cb_data);
strbuf_release(&name);
return retval;
}

int update_ref(const char *action, const char *refname,
const unsigned char *sha1, const unsigned char *oldval,
int flags, enum action_on_err onerr)
{
static struct ref_lock *lock;
lock = lock_any_ref_for_update(refname, oldval, flags);
if (!lock) {
const char *str = "Cannot lock the ref '%s'.";
switch (onerr) {
case MSG_ON_ERR: error(str, refname); break;
case DIE_ON_ERR: die(str, refname); break;
case QUIET_ON_ERR: break;
}
return 1;
}
if (write_ref_sha1(lock, sha1, action) < 0) {
const char *str = "Cannot update the ref '%s'.";
switch (onerr) {
case MSG_ON_ERR: error(str, refname); break;
case DIE_ON_ERR: die(str, refname); break;
case QUIET_ON_ERR: break;
}
return 1;
}
return 0;
}

struct ref *find_ref_by_name(const struct ref *list, const char *name)
{
for ( ; list; list = list->next)
if (!strcmp(list->name, name))
return (struct ref *)list;
return NULL;
}

/*
* generate a format suitable for scanf from a ref_rev_parse_rules
* rule, that is replace the "%.*s" spec with a "%s" spec
*/
static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
{
char *spec;

spec = strstr(rule, "%.*s");
if (!spec || strstr(spec + 4, "%.*s"))
die("invalid rule in ref_rev_parse_rules: %s", rule);

/* copy all until spec */
strncpy(scanf_fmt, rule, spec - rule);
scanf_fmt[spec - rule] = '\0';
/* copy new spec */
strcat(scanf_fmt, "%s");
/* copy remaining rule */
strcat(scanf_fmt, spec + 4);

return;
}

char *shorten_unambiguous_ref(const char *refname, int strict)
{
int i;
static char **scanf_fmts;
static int nr_rules;
char *short_name;

/* pre generate scanf formats from ref_rev_parse_rules[] */
if (!nr_rules) {
size_t total_len = 0;

/* the rule list is NULL terminated, count them first */
for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
/* no +1 because strlen("%s") < strlen("%.*s") */
total_len += strlen(ref_rev_parse_rules[nr_rules]);

scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);

total_len = 0;
for (i = 0; i < nr_rules; i++) {
scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
+ total_len;
gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
total_len += strlen(ref_rev_parse_rules[i]);
}
}

/* 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);
}
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