git/refs.c
Nicolas Pitre 605fac8b5b update HEAD reflog when branch pointed to by HEAD is directly modified
The HEAD reflog is updated as well as the reflog for the branch pointed
to by HEAD whenever it is referenced with "HEAD".

There are some cases where a specific branch may be modified directly.
In those cases, the HEAD reflog should be updated as well if it is a
symref to that branch in order to be consistent.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-03-22 03:02:48 -07:00

1290 lines
31 KiB
C

#include "cache.h"
#include "refs.h"
#include "object.h"
#include "tag.h"
/* ISSYMREF=01 and ISPACKED=02 are public interfaces */
#define REF_KNOWS_PEELED 04
struct ref_list {
struct ref_list *next;
unsigned char flag; /* ISSYMREF? ISPACKED? */
unsigned char sha1[20];
unsigned char peeled[20];
char name[FLEX_ARRAY];
};
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 struct ref_list *add_ref(const char *name, const unsigned char *sha1,
int flag, struct ref_list *list,
struct ref_list **new_entry)
{
int len;
struct ref_list **p = &list, *entry;
/* Find the place to insert the ref into.. */
while ((entry = *p) != NULL) {
int cmp = strcmp(entry->name, name);
if (cmp > 0)
break;
/* Same as existing entry? */
if (!cmp) {
if (new_entry)
*new_entry = entry;
return list;
}
p = &entry->next;
}
/* Allocate it and add it in.. */
len = strlen(name) + 1;
entry = xmalloc(sizeof(struct ref_list) + len);
hashcpy(entry->sha1, sha1);
hashclr(entry->peeled);
memcpy(entry->name, name, len);
entry->flag = flag;
entry->next = *p;
*p = entry;
if (new_entry)
*new_entry = entry;
return list;
}
/*
* Future: need to be in "struct repository"
* when doing a full libification.
*/
struct cached_refs {
char did_loose;
char did_packed;
struct ref_list *loose;
struct ref_list *packed;
} cached_refs;
static void free_ref_list(struct ref_list *list)
{
struct ref_list *next;
for ( ; list; list = next) {
next = list->next;
free(list);
}
}
static void invalidate_cached_refs(void)
{
struct cached_refs *ca = &cached_refs;
if (ca->did_loose && ca->loose)
free_ref_list(ca->loose);
if (ca->did_packed && ca->packed)
free_ref_list(ca->packed);
ca->loose = ca->packed = NULL;
ca->did_loose = ca->did_packed = 0;
}
static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
{
struct ref_list *list = NULL;
struct ref_list *last = NULL;
char refline[PATH_MAX];
int flag = REF_ISPACKED;
while (fgets(refline, sizeof(refline), f)) {
unsigned char sha1[20];
const char *name;
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;
}
name = parse_ref_line(refline, sha1);
if (name) {
list = add_ref(name, sha1, flag, list, &last);
continue;
}
if (last &&
refline[0] == '^' &&
strlen(refline) == 42 &&
refline[41] == '\n' &&
!get_sha1_hex(refline + 1, sha1))
hashcpy(last->peeled, sha1);
}
cached_refs->packed = list;
}
static struct ref_list *get_packed_refs(void)
{
if (!cached_refs.did_packed) {
FILE *f = fopen(git_path("packed-refs"), "r");
cached_refs.packed = NULL;
if (f) {
read_packed_refs(f, &cached_refs);
fclose(f);
}
cached_refs.did_packed = 1;
}
return cached_refs.packed;
}
static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
{
DIR *dir = opendir(git_path("%s", base));
if (dir) {
struct dirent *de;
int baselen = strlen(base);
char *ref = xmalloc(baselen + 257);
memcpy(ref, base, baselen);
if (baselen && base[baselen-1] != '/')
ref[baselen++] = '/';
while ((de = readdir(dir)) != NULL) {
unsigned char sha1[20];
struct stat st;
int flag;
int namelen;
if (de->d_name[0] == '.')
continue;
namelen = strlen(de->d_name);
if (namelen > 255)
continue;
if (has_extension(de->d_name, ".lock"))
continue;
memcpy(ref + baselen, de->d_name, namelen+1);
if (stat(git_path("%s", ref), &st) < 0)
continue;
if (S_ISDIR(st.st_mode)) {
list = get_ref_dir(ref, list);
continue;
}
if (!resolve_ref(ref, sha1, 1, &flag)) {
error("%s points nowhere!", ref);
continue;
}
list = add_ref(ref, sha1, flag, list, NULL);
}
free(ref);
closedir(dir);
}
return list;
}
static struct ref_list *get_loose_refs(void)
{
if (!cached_refs.did_loose) {
cached_refs.loose = get_ref_dir("refs", NULL);
cached_refs.did_loose = 1;
}
return cached_refs.loose;
}
/* We allow "recursive" symbolic refs. Only within reason, though */
#define MAXDEPTH 5
const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
{
int depth = MAXDEPTH, len;
char buffer[256];
static char ref_buffer[256];
if (flag)
*flag = 0;
for (;;) {
const char *path = git_path("%s", ref);
struct stat st;
char *buf;
int fd;
if (--depth < 0)
return NULL;
/* Special case: non-existing file.
* Not having the refs/heads/new-branch is OK
* if we are writing into it, so is .git/HEAD
* that points at refs/heads/master still to be
* born. It is NOT OK if we are resolving for
* reading.
*/
if (lstat(path, &st) < 0) {
struct ref_list *list = get_packed_refs();
while (list) {
if (!strcmp(ref, list->name)) {
hashcpy(sha1, list->sha1);
if (flag)
*flag |= REF_ISPACKED;
return ref;
}
list = list->next;
}
if (reading || errno != ENOENT)
return NULL;
hashclr(sha1);
return ref;
}
/* Follow "normalized" - ie "refs/.." symlinks by hand */
if (S_ISLNK(st.st_mode)) {
len = readlink(path, buffer, sizeof(buffer)-1);
if (len >= 5 && !memcmp("refs/", buffer, 5)) {
buffer[len] = 0;
strcpy(ref_buffer, buffer);
ref = ref_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);
/*
* Is it a symbolic ref?
*/
if (len < 4 || memcmp("ref:", buffer, 4))
break;
buf = buffer + 4;
len -= 4;
while (len && isspace(*buf))
buf++, len--;
while (len && isspace(buf[len-1]))
len--;
buf[len] = 0;
memcpy(ref_buffer, buf, len + 1);
ref = ref_buffer;
if (flag)
*flag |= REF_ISSYMREF;
}
if (len < 40 || get_sha1_hex(buffer, sha1))
return NULL;
return ref;
}
int read_ref(const char *ref, unsigned char *sha1)
{
if (resolve_ref(ref, sha1, 1, NULL))
return 0;
return -1;
}
static int do_one_ref(const char *base, each_ref_fn fn, int trim,
void *cb_data, struct ref_list *entry)
{
if (strncmp(base, entry->name, trim))
return 0;
if (is_null_sha1(entry->sha1))
return 0;
if (!has_sha1_file(entry->sha1)) {
error("%s does not point to a valid object!", entry->name);
return 0;
}
return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
}
int peel_ref(const char *ref, unsigned char *sha1)
{
int flag;
unsigned char base[20];
struct object *o;
if (!resolve_ref(ref, base, 1, &flag))
return -1;
if ((flag & REF_ISPACKED)) {
struct ref_list *list = get_packed_refs();
while (list) {
if (!strcmp(list->name, ref)) {
if (list->flag & REF_KNOWS_PEELED) {
hashcpy(sha1, list->peeled);
return 0;
}
/* older pack-refs did not leave peeled ones */
break;
}
list = list->next;
}
}
/* fallback - callers should not call this for unpacked refs */
o = parse_object(base);
if (o->type == OBJ_TAG) {
o = deref_tag(o, ref, 0);
if (o) {
hashcpy(sha1, o->sha1);
return 0;
}
}
return -1;
}
static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
void *cb_data)
{
int retval;
struct ref_list *packed = get_packed_refs();
struct ref_list *loose = get_loose_refs();
while (packed && loose) {
struct ref_list *entry;
int cmp = strcmp(packed->name, loose->name);
if (!cmp) {
packed = packed->next;
continue;
}
if (cmp > 0) {
entry = loose;
loose = loose->next;
} else {
entry = packed;
packed = packed->next;
}
retval = do_one_ref(base, fn, trim, cb_data, entry);
if (retval)
return retval;
}
for (packed = packed ? packed : loose; packed; packed = packed->next) {
retval = do_one_ref(base, fn, trim, cb_data, packed);
if (retval)
return retval;
}
return 0;
}
int head_ref(each_ref_fn fn, void *cb_data)
{
unsigned char sha1[20];
int flag;
if (resolve_ref("HEAD", sha1, 1, &flag))
return fn("HEAD", sha1, flag, cb_data);
return 0;
}
int for_each_ref(each_ref_fn fn, void *cb_data)
{
return do_for_each_ref("refs/", fn, 0, cb_data);
}
int for_each_tag_ref(each_ref_fn fn, void *cb_data)
{
return do_for_each_ref("refs/tags/", fn, 10, cb_data);
}
int for_each_branch_ref(each_ref_fn fn, void *cb_data)
{
return do_for_each_ref("refs/heads/", fn, 11, cb_data);
}
int for_each_remote_ref(each_ref_fn fn, void *cb_data)
{
return do_for_each_ref("refs/remotes/", fn, 13, cb_data);
}
/* NEEDSWORK: This is only used by ssh-upload and it should go; the
* caller should do resolve_ref or read_ref like everybody else. Or
* maybe everybody else should use get_ref_sha1() instead of doing
* read_ref().
*/
int get_ref_sha1(const char *ref, unsigned char *sha1)
{
if (check_ref_format(ref))
return -1;
return read_ref(mkpath("refs/%s", ref), sha1);
}
/*
* 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 "/".
*/
static inline int bad_ref_char(int ch)
{
return (((unsigned) ch) <= ' ' ||
ch == '~' || ch == '^' || ch == ':' ||
/* 2.13 Pattern Matching Notation */
ch == '?' || ch == '*' || ch == '[');
}
int check_ref_format(const char *ref)
{
int ch, level;
const char *cp = ref;
level = 0;
while (1) {
while ((ch = *cp++) == '/')
; /* tolerate duplicated slashes */
if (!ch)
return -1; /* should not end with slashes */
/* we are at the beginning of the path component */
if (ch == '.' || bad_ref_char(ch))
return -1;
/* scan the rest of the path component */
while ((ch = *cp++) != 0) {
if (bad_ref_char(ch))
return -1;
if (ch == '/')
break;
if (ch == '.' && *cp == '.')
return -1;
}
level++;
if (!ch) {
if (level < 2)
return -2; /* at least of form "heads/blah" */
return 0;
}
}
}
static struct ref_lock *verify_lock(struct ref_lock *lock,
const unsigned char *old_sha1, int mustexist)
{
if (!resolve_ref(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_dir_recursive(char *path, int len)
{
DIR *dir = opendir(path);
struct dirent *e;
int ret = 0;
if (!dir)
return -1;
if (path[len-1] != '/')
path[len++] = '/';
while ((e = readdir(dir)) != NULL) {
struct stat st;
int namlen;
if ((e->d_name[0] == '.') &&
((e->d_name[1] == 0) ||
((e->d_name[1] == '.') && e->d_name[2] == 0)))
continue; /* "." and ".." */
namlen = strlen(e->d_name);
if ((len + namlen < PATH_MAX) &&
strcpy(path + len, e->d_name) &&
!lstat(path, &st) &&
S_ISDIR(st.st_mode) &&
!remove_empty_dir_recursive(path, len + namlen))
continue; /* happy */
/* path too long, stat fails, or non-directory still exists */
ret = -1;
break;
}
closedir(dir);
if (!ret) {
path[len] = 0;
ret = rmdir(path);
}
return ret;
}
static int remove_empty_directories(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.
*/
char path[PATH_MAX];
int len = strlen(file);
if (len >= PATH_MAX) /* path too long ;-) */
return -1;
strcpy(path, file);
return remove_empty_dir_recursive(path, len);
}
static int is_refname_available(const char *ref, const char *oldref,
struct ref_list *list, int quiet)
{
int namlen = strlen(ref); /* e.g. 'foo/bar' */
while (list) {
/* list->name could be 'foo' or 'foo/bar/baz' */
if (!oldref || strcmp(oldref, list->name)) {
int len = strlen(list->name);
int cmplen = (namlen < len) ? namlen : len;
const char *lead = (namlen < len) ? list->name : ref;
if (!strncmp(ref, list->name, cmplen) &&
lead[cmplen] == '/') {
if (!quiet)
error("'%s' exists; cannot create '%s'",
list->name, ref);
return 0;
}
}
list = list->next;
}
return 1;
}
static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int *flag)
{
char *ref_file;
const char *orig_ref = ref;
struct ref_lock *lock;
struct stat st;
int last_errno = 0;
int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
lock = xcalloc(1, sizeof(struct ref_lock));
lock->lock_fd = -1;
ref = resolve_ref(ref, lock->old_sha1, mustexist, flag);
if (!ref && 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_ref);
if (remove_empty_directories(ref_file)) {
last_errno = errno;
error("there are still refs under '%s'", orig_ref);
goto error_return;
}
ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, flag);
}
if (!ref) {
last_errno = errno;
error("unable to resolve reference %s: %s",
orig_ref, strerror(errno));
goto error_return;
}
/* 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 (is_null_sha1(lock->old_sha1) &&
!is_refname_available(ref, NULL, get_packed_refs(), 0))
goto error_return;
lock->lk = xcalloc(1, sizeof(struct lock_file));
lock->ref_name = xstrdup(ref);
lock->orig_ref_name = xstrdup(orig_ref);
ref_file = git_path("%s", ref);
lock->force_write = lstat(ref_file, &st) && errno == ENOENT;
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, 1);
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 *ref, const unsigned char *old_sha1)
{
char refpath[PATH_MAX];
if (check_ref_format(ref))
return NULL;
strcpy(refpath, mkpath("refs/%s", ref));
return lock_ref_sha1_basic(refpath, old_sha1, NULL);
}
struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1)
{
if (check_ref_format(ref) == -1)
return NULL;
return lock_ref_sha1_basic(ref, old_sha1, NULL);
}
static struct lock_file packlock;
static int repack_without_ref(const char *refname)
{
struct ref_list *list, *packed_ref_list;
int fd;
int found = 0;
packed_ref_list = get_packed_refs();
for (list = packed_ref_list; list; list = list->next) {
if (!strcmp(refname, list->name)) {
found = 1;
break;
}
}
if (!found)
return 0;
fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
if (fd < 0)
return error("cannot delete '%s' from packed refs", refname);
for (list = packed_ref_list; list; list = list->next) {
char line[PATH_MAX + 100];
int len;
if (!strcmp(refname, list->name))
continue;
len = snprintf(line, sizeof(line), "%s %s\n",
sha1_to_hex(list->sha1), list->name);
/* this should not happen but just being defensive */
if (len > sizeof(line))
die("too long a refname '%s'", list->name);
write_or_die(fd, line, len);
}
return commit_lock_file(&packlock);
}
int delete_ref(const char *refname, unsigned char *sha1)
{
struct ref_lock *lock;
int err, i, ret = 0, flag = 0;
lock = lock_ref_sha1_basic(refname, sha1, &flag);
if (!lock)
return 1;
if (!(flag & REF_ISPACKED)) {
/* loose */
i = strlen(lock->lk->filename) - 5; /* .lock */
lock->lk->filename[i] = 0;
err = unlink(lock->lk->filename);
if (err) {
ret = 1;
error("unlink(%s) failed: %s",
lock->lk->filename, strerror(errno));
}
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);
err = unlink(git_path("logs/%s", lock->ref_name));
if (err && errno != ENOENT)
fprintf(stderr, "warning: unlink(%s) failed: %s",
git_path("logs/%s", lock->ref_name), strerror(errno));
invalidate_cached_refs();
unlock_ref(lock);
return ret;
}
int rename_ref(const char *oldref, const char *newref, const char *logmsg)
{
static const char renamed_ref[] = "RENAMED-REF";
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", oldref), &loginfo);
if (S_ISLNK(loginfo.st_mode))
return error("reflog for %s is a symlink", oldref);
if (!resolve_ref(oldref, orig_sha1, 1, &flag))
return error("refname %s not found", oldref);
if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
return 1;
if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
return 1;
lock = lock_ref_sha1_basic(renamed_ref, NULL, NULL);
if (!lock)
return error("unable to lock %s", renamed_ref);
lock->force_write = 1;
if (write_ref_sha1(lock, orig_sha1, logmsg))
return error("unable to save current sha1 in %s", renamed_ref);
if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
oldref, strerror(errno));
if (delete_ref(oldref, orig_sha1)) {
error("unable to delete old %s", oldref);
goto rollback;
}
if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1)) {
if (errno==EISDIR) {
if (remove_empty_directories(git_path("%s", newref))) {
error("Directory not empty: %s", newref);
goto rollback;
}
} else {
error("unable to delete existing %s", newref);
goto rollback;
}
}
if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
error("unable to create directory for %s", newref);
goto rollback;
}
retry:
if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
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", newref))) {
error("Directory not empty: logs/%s", newref);
goto rollback;
}
goto retry;
} else {
error("unable to move logfile tmp-renamed-log to logs/%s: %s",
newref, strerror(errno));
goto rollback;
}
}
logmoved = log;
lock = lock_ref_sha1_basic(newref, NULL, NULL);
if (!lock) {
error("unable to lock %s for update", newref);
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", newref);
goto rollback;
}
if (!prefixcmp(oldref, "refs/heads/") &&
!prefixcmp(newref, "refs/heads/")) {
char oldsection[1024], newsection[1024];
snprintf(oldsection, 1024, "branch.%s", oldref + 11);
snprintf(newsection, 1024, "branch.%s", newref + 11);
if (git_config_rename_section(oldsection, newsection) < 0)
return 1;
}
return 0;
rollback:
lock = lock_ref_sha1_basic(oldref, NULL, NULL);
if (!lock) {
error("unable to lock %s for rollback", oldref);
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", oldref);
log_all_ref_updates = flag;
rollbacklog:
if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
error("unable to restore logfile %s from %s: %s",
oldref, newref, strerror(errno));
if (!logmoved && log &&
rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
error("unable to restore logfile %s from tmp-renamed-log: %s",
oldref, strerror(errno));
return 1;
}
void unlock_ref(struct ref_lock *lock)
{
if (lock->lock_fd >= 0) {
close(lock->lock_fd);
/* 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);
}
static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
const unsigned char *new_sha1, const char *msg)
{
int logfd, written, oflags = O_APPEND | O_WRONLY;
unsigned maxlen, len;
int msglen;
char *log_file, *logrec;
const char *committer;
if (log_all_ref_updates < 0)
log_all_ref_updates = !is_bare_repository();
log_file = git_path("logs/%s", ref_name);
if (log_all_ref_updates &&
(!prefixcmp(ref_name, "refs/heads/") ||
!prefixcmp(ref_name, "refs/remotes/") ||
!strcmp(ref_name, "HEAD"))) {
if (safe_create_leading_directories(log_file) < 0)
return error("unable to create directory for %s",
log_file);
oflags |= O_CREAT;
}
logfd = open(log_file, oflags, 0666);
if (logfd < 0) {
if (!(oflags & O_CREAT) && errno == ENOENT)
return 0;
if ((oflags & O_CREAT) && errno == EISDIR) {
if (remove_empty_directories(log_file)) {
return error("There are still logs under '%s'",
log_file);
}
logfd = open(log_file, oflags, 0666);
}
if (logfd < 0)
return error("Unable to append to %s: %s",
log_file, strerror(errno));
}
adjust_shared_perm(log_file);
msglen = 0;
if (msg) {
/* clean up the message and make sure it is a single line */
for ( ; *msg; msg++)
if (!isspace(*msg))
break;
if (*msg) {
const char *ep = strchr(msg, '\n');
if (ep)
msglen = ep - msg;
else
msglen = strlen(msg);
}
}
committer = git_committer_info(-1);
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 += sprintf(logrec + len - 1, "\t%.*s\n", msglen, msg) - 1;
written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
free(logrec);
close(logfd);
if (written != len)
return error("Unable to append to %s", log_file);
return 0;
}
int write_ref_sha1(struct ref_lock *lock,
const unsigned char *sha1, const char *logmsg)
{
static char term = '\n';
if (!lock)
return -1;
if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
unlock_ref(lock);
return 0;
}
if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
write_in_full(lock->lock_fd, &term, 1) != 1
|| close(lock->lock_fd) < 0) {
error("Couldn't write %s", lock->lk->filename);
unlock_ref(lock);
return -1;
}
invalidate_cached_refs();
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("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_lock_file(lock->lk)) {
error("Couldn't set %s", lock->ref_name);
unlock_ref(lock);
return -1;
}
lock->lock_fd = -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 = xstrdup(git_path("%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);
close(fd);
if (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(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;
char *msg;
line += 82;
for (ep = line; ep < endp && *ep != '\n'; ep++)
;
msg = xmalloc(ep - line + 1);
memcpy(msg, line, ep - line);
msg[ep - line] = 0;
return msg;
}
int read_ref_at(const char *ref, 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", ref);
logfd = open(logfile, O_RDONLY, 0);
if (logfd < 0)
die("Unable to read log %s: %s", logfile, strerror(errno));
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)) {
fprintf(stderr,
"warning: Log %s has gap after %s.\n",
logfile, show_rfc2822_date(date, tz));
}
}
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)) {
fprintf(stderr,
"warning: Log %s unexpectedly ended on %s.\n",
logfile, show_rfc2822_date(date, tz));
}
}
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 (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_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
{
const char *logfile;
FILE *logfp;
char buf[1024];
int ret = 0;
logfile = git_path("logs/%s", ref);
logfp = fopen(logfile, "r");
if (!logfp)
return -1;
while (fgets(buf, sizeof(buf), logfp)) {
unsigned char osha1[20], nsha1[20];
char *email_end, *message;
unsigned long timestamp;
int len, tz;
/* old SP new SP name <email> SP time TAB msg LF */
len = strlen(buf);
if (len < 83 || buf[len-1] != '\n' ||
get_sha1_hex(buf, osha1) || buf[40] != ' ' ||
get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' ||
!(email_end = strchr(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, buf+82, timestamp, tz, message, cb_data);
if (ret)
break;
}
fclose(logfp);
return ret;
}
static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
{
DIR *dir = opendir(git_path("logs/%s", base));
int retval = 0;
if (dir) {
struct dirent *de;
int baselen = strlen(base);
char *log = xmalloc(baselen + 257);
memcpy(log, base, baselen);
if (baselen && base[baselen-1] != '/')
log[baselen++] = '/';
while ((de = readdir(dir)) != NULL) {
struct stat st;
int namelen;
if (de->d_name[0] == '.')
continue;
namelen = strlen(de->d_name);
if (namelen > 255)
continue;
if (has_extension(de->d_name, ".lock"))
continue;
memcpy(log + baselen, de->d_name, namelen+1);
if (stat(git_path("logs/%s", log), &st) < 0)
continue;
if (S_ISDIR(st.st_mode)) {
retval = do_for_each_reflog(log, fn, cb_data);
} else {
unsigned char sha1[20];
if (!resolve_ref(log, sha1, 0, NULL))
retval = error("bad ref for %s", log);
else
retval = fn(log, sha1, 0, cb_data);
}
if (retval)
break;
}
free(log);
closedir(dir);
}
else if (*base)
return errno;
return retval;
}
int for_each_reflog(each_ref_fn fn, void *cb_data)
{
return do_for_each_reflog("", fn, cb_data);
}