Merge branch 'jc/rw-prefix'
[gitweb.git] / refs.c
diff --git a/refs.c b/refs.c
index 91c8c44a159b3e4c1b7bb35c5662502642758ab2..713ca467368e24f6112663b7b96921f9d1bbc145 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -104,6 +104,11 @@ int create_symref(const char *git_HEAD, const char *refs_heads_master)
                error("Unable to create %s", git_HEAD);
                return -3;
        }
+       if (adjust_shared_perm(git_HEAD)) {
+               unlink(lockpath);
+               error("Unable to fix permissions on %s", lockpath);
+               return -4;
+       }
        return 0;
 }
 
@@ -142,6 +147,8 @@ static int do_for_each_ref(const char *base, int (*fn)(const char *path, const u
                        namelen = strlen(de->d_name);
                        if (namelen > 255)
                                continue;
+                       if (namelen>5 && !strcmp(de->d_name+namelen-5,".lock"))
+                               continue;
                        memcpy(path + baselen, de->d_name, namelen+1);
                        if (stat(git_path("%s", path), &st) < 0)
                                continue;
@@ -257,7 +264,7 @@ int check_ref_format(const char *ref)
        }
 }
 
-static struct ref_lockverify_lock(struct ref_lock *lock,
+static struct ref_lock *verify_lock(struct ref_lock *lock,
        const unsigned char *old_sha1, int mustexist)
 {
        char buf[40];
@@ -283,11 +290,12 @@ static struct ref_lock* verify_lock(struct ref_lock *lock,
        return lock;
 }
 
-static struct ref_locklock_ref_sha1_basic(const char *path,
+static struct ref_lock *lock_ref_sha1_basic(const char *path,
        int plen,
        const unsigned char *old_sha1, int mustexist)
 {
        struct ref_lock *lock;
+       struct stat st;
 
        lock = xcalloc(1, sizeof(struct ref_lock));
        lock->lock_fd = -1;
@@ -295,21 +303,21 @@ static struct ref_lock* lock_ref_sha1_basic(const char *path,
        plen = strlen(path) - plen;
        path = resolve_ref(path, lock->old_sha1, mustexist);
        if (!path) {
-               error("Can't read ref %s", path);
                unlock_ref(lock);
                return NULL;
        }
+       lock->lk = xcalloc(1, sizeof(struct lock_file));
 
        lock->ref_file = strdup(path);
-       lock->lock_file = strdup(mkpath("%s.lock", lock->ref_file));
+       lock->log_file = strdup(git_path("logs/%s", lock->ref_file + plen));
+       lock->force_write = lstat(lock->ref_file, &st) && errno == ENOENT;
 
-       if (safe_create_leading_directories(lock->lock_file))
-               die("unable to create directory for %s", lock->lock_file);
-       lock->lock_fd = open(lock->lock_file,
-               O_WRONLY | O_CREAT | O_EXCL, 0666);
+       if (safe_create_leading_directories(lock->ref_file))
+               die("unable to create directory for %s", lock->ref_file);
+       lock->lock_fd = hold_lock_file_for_update(lock->lk, lock->ref_file);
        if (lock->lock_fd < 0) {
                error("Couldn't open lock file %s: %s",
-                       lock->lock_file, strerror(errno));
+                     lock->lk->filename, strerror(errno));
                unlock_ref(lock);
                return NULL;
        }
@@ -317,35 +325,87 @@ static struct ref_lock* lock_ref_sha1_basic(const char *path,
        return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
 }
 
-struct ref_locklock_ref_sha1(const char *ref,
+struct ref_lock *lock_ref_sha1(const char *ref,
        const unsigned char *old_sha1, int mustexist)
 {
        if (check_ref_format(ref))
                return NULL;
        return lock_ref_sha1_basic(git_path("refs/%s", ref),
-               strlen(ref), old_sha1, mustexist);
+               5 + strlen(ref), old_sha1, mustexist);
 }
 
-struct ref_locklock_any_ref_for_update(const char *ref,
+struct ref_lock *lock_any_ref_for_update(const char *ref,
        const unsigned char *old_sha1, int mustexist)
 {
        return lock_ref_sha1_basic(git_path("%s", ref),
                strlen(ref), old_sha1, mustexist);
 }
 
-void unlock_ref (struct ref_lock *lock)
+void unlock_ref(struct ref_lock *lock)
 {
        if (lock->lock_fd >= 0) {
                close(lock->lock_fd);
-               unlink(lock->lock_file);
+               /* Do not free lock->lk -- atexit() still looks at them */
+               if (lock->lk)
+                       rollback_lock_file(lock->lk);
        }
        if (lock->ref_file)
                free(lock->ref_file);
-       if (lock->lock_file)
-               free(lock->lock_file);
+       if (lock->log_file)
+               free(lock->log_file);
        free(lock);
 }
 
+static int log_ref_write(struct ref_lock *lock,
+       const unsigned char *sha1, const char *msg)
+{
+       int logfd, written, oflags = O_APPEND | O_WRONLY;
+       unsigned maxlen, len;
+       char *logrec;
+       const char *comitter;
+
+       if (log_all_ref_updates) {
+               if (safe_create_leading_directories(lock->log_file) < 0)
+                       return error("unable to create directory for %s",
+                               lock->log_file);
+               oflags |= O_CREAT;
+       }
+
+       logfd = open(lock->log_file, oflags, 0666);
+       if (logfd < 0) {
+               if (!log_all_ref_updates && errno == ENOENT)
+                       return 0;
+               return error("Unable to append to %s: %s",
+                       lock->log_file, strerror(errno));
+       }
+
+       setup_ident();
+       comitter = git_committer_info(1);
+       if (msg) {
+               maxlen = strlen(comitter) + strlen(msg) + 2*40 + 5;
+               logrec = xmalloc(maxlen);
+               len = snprintf(logrec, maxlen, "%s %s %s\t%s\n",
+                       sha1_to_hex(lock->old_sha1),
+                       sha1_to_hex(sha1),
+                       comitter,
+                       msg);
+       }
+       else {
+               maxlen = strlen(comitter) + 2*40 + 4;
+               logrec = xmalloc(maxlen);
+               len = snprintf(logrec, maxlen, "%s %s %s\n",
+                       sha1_to_hex(lock->old_sha1),
+                       sha1_to_hex(sha1),
+                       comitter);
+       }
+       written = len <= maxlen ? write(logfd, logrec, len) : -1;
+       free(logrec);
+       close(logfd);
+       if (written != len)
+               return error("Unable to append to %s", lock->log_file);
+       return 0;
+}
+
 int write_ref_sha1(struct ref_lock *lock,
        const unsigned char *sha1, const char *logmsg)
 {
@@ -353,18 +413,22 @@ int write_ref_sha1(struct ref_lock *lock,
 
        if (!lock)
                return -1;
-       if (!memcmp(lock->old_sha1, sha1, 20)) {
+       if (!lock->force_write && !memcmp(lock->old_sha1, sha1, 20)) {
                unlock_ref(lock);
                return 0;
        }
        if (write(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
            write(lock->lock_fd, &term, 1) != 1
                || close(lock->lock_fd) < 0) {
-               error("Couldn't write %s", lock->lock_file);
+               error("Couldn't write %s", lock->lk->filename);
                unlock_ref(lock);
                return -1;
        }
-       if (rename(lock->lock_file, lock->ref_file) < 0) {
+       if (log_ref_write(lock, sha1, logmsg) < 0) {
+               unlock_ref(lock);
+               return -1;
+       }
+       if (commit_lock_file(lock->lk)) {
                error("Couldn't set %s", lock->ref_file);
                unlock_ref(lock);
                return -1;
@@ -373,3 +437,84 @@ int write_ref_sha1(struct ref_lock *lock,
        unlock_ref(lock);
        return 0;
 }
+
+int read_ref_at(const char *ref, unsigned long at_time, unsigned char *sha1)
+{
+       const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
+       char *tz_c;
+       int logfd, tz;
+       struct stat st;
+       unsigned long date;
+       unsigned char logged_sha1[20];
+
+       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);
+       logdata = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, logfd, 0);
+       close(logfd);
+
+       lastrec = NULL;
+       rec = logend = logdata + st.st_size;
+       while (logdata < rec) {
+               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) {
+                       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 (memcmp(logged_sha1, sha1, 20)) {
+                                       tz = strtoul(tz_c, NULL, 10);
+                                       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 (memcmp(logged_sha1, sha1, 20)) {
+                                       tz = strtoul(tz_c, NULL, 10);
+                                       fprintf(stderr,
+                                               "warning: Log %s unexpectedly ended on %s.\n",
+                                               logfile, show_rfc2822_date(date, tz));
+                               }
+                       }
+                       munmap((void*)logdata, st.st_size);
+                       return 0;
+               }
+               lastrec = rec;
+       }
+
+       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);
+       munmap((void*)logdata, st.st_size);
+       fprintf(stderr, "warning: Log %s only goes back to %s.\n",
+               logfile, show_rfc2822_date(date, tz));
+       return 0;
+}