Merge branch 'journal'

1 files changed, 2078 insertions, 0 deletions

diff --git a/src/journal/journal-file.c b/src/journal/journal-file.c
new file mode 100644
index 0000000000..190bfb996b
--- /dev/null
+++ b/src/journal/journal-file.c
@@ -0,0 +1,2078 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2011 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/mman.h>
+#include <errno.h>
+#include <sys/uio.h>
+#include <unistd.h>
+#include <sys/statvfs.h>
+#include <fcntl.h>
+#include <stddef.h>
+
+#include "journal-def.h"
+#include "journal-file.h"
+#include "lookup3.h"
+#include "compress.h"
+
+#define DEFAULT_DATA_HASH_TABLE_SIZE (2047ULL*16ULL)
+#define DEFAULT_FIELD_HASH_TABLE_SIZE (2047ULL*16ULL)
+
+#define DEFAULT_WINDOW_SIZE (128ULL*1024ULL*1024ULL)
+
+#define COMPRESSION_SIZE_THRESHOLD (64ULL)
+
+static const char signature[] = { 'L', 'P', 'K', 'S', 'H', 'H', 'R', 'H' };
+
+#define ALIGN64(x) (((x) + 7ULL) & ~7ULL)
+
+void journal_file_close(JournalFile *f) {
+        int t;
+
+        assert(f);
+
+        if (f->header && f->writable)
+                f->header->state = STATE_OFFLINE;
+
+
+        for (t = 0; t < _WINDOW_MAX; t++)
+                if (f->windows[t].ptr)
+                        munmap(f->windows[t].ptr, f->windows[t].size);
+
+        if (f->fd >= 0)
+                close_nointr_nofail(f->fd);
+
+        free(f->path);
+
+#ifdef HAVE_XZ
+        free(f->compress_buffer);
+#endif
+
+        free(f);
+}
+
+static int journal_file_init_header(JournalFile *f, JournalFile *template) {
+        Header h;
+        ssize_t k;
+        int r;
+
+        assert(f);
+
+        zero(h);
+        memcpy(h.signature, signature, 8);
+        h.arena_offset = htole64(ALIGN64(sizeof(h)));
+
+        r = sd_id128_randomize(&h.file_id);
+        if (r < 0)
+                return r;
+
+        if (template) {
+                h.seqnum_id = template->header->seqnum_id;
+                h.seqnum = template->header->seqnum;
+        } else
+                h.seqnum_id = h.file_id;
+
+        k = pwrite(f->fd, &h, sizeof(h), 0);
+        if (k < 0)
+                return -errno;
+
+        if (k != sizeof(h))
+                return -EIO;
+
+        return 0;
+}
+
+static int journal_file_refresh_header(JournalFile *f) {
+        int r;
+        sd_id128_t boot_id;
+
+        assert(f);
+
+        r = sd_id128_get_machine(&f->header->machine_id);
+        if (r < 0)
+                return r;
+
+        r = sd_id128_get_boot(&boot_id);
+        if (r < 0)
+                return r;
+
+        if (sd_id128_equal(boot_id, f->header->boot_id))
+                f->tail_entry_monotonic_valid = true;
+
+        f->header->boot_id = boot_id;
+
+        f->header->state = STATE_ONLINE;
+        return 0;
+}
+
+static int journal_file_verify_header(JournalFile *f) {
+        assert(f);
+
+        if (memcmp(f->header, signature, 8))
+                return -EBADMSG;
+
+#ifdef HAVE_XZ
+        if ((le64toh(f->header->incompatible_flags) & ~HEADER_INCOMPATIBLE_COMPRESSED) != 0)
+                return -EPROTONOSUPPORT;
+#else
+        if (f->header->incompatible_flags != 0)
+                return -EPROTONOSUPPORT;
+#endif
+
+        if ((uint64_t) f->last_stat.st_size < (le64toh(f->header->arena_offset) + le64toh(f->header->arena_size)))
+                return -ENODATA;
+
+        if (f->writable) {
+                uint32_t state;
+                sd_id128_t machine_id;
+                int r;
+
+                r = sd_id128_get_machine(&machine_id);
+                if (r < 0)
+                        return r;
+
+                if (!sd_id128_equal(machine_id, f->header->machine_id))
+                        return -EHOSTDOWN;
+
+                state = f->header->state;
+
+                if (state == STATE_ONLINE)
+                        log_debug("Journal file %s is already online. Assuming unclean closing. Ignoring.", f->path);
+                else if (state == STATE_ARCHIVED)
+                        return -ESHUTDOWN;
+                else if (state != STATE_OFFLINE)
+                        log_debug("Journal file %s has unknown state %u. Ignoring.", f->path, state);
+        }
+
+        return 0;
+}
+
+static int journal_file_allocate(JournalFile *f, uint64_t offset, uint64_t size) {
+        uint64_t old_size, new_size;
+
+        assert(f);
+
+        /* We assume that this file is not sparse, and we know that
+         * for sure, since we always call posix_fallocate()
+         * ourselves */
+
+        old_size =
+                le64toh(f->header->arena_offset) +
+                le64toh(f->header->arena_size);
+
+        new_size = PAGE_ALIGN(offset + size);
+        if (new_size < le64toh(f->header->arena_offset))
+                new_size = le64toh(f->header->arena_offset);
+
+        if (new_size <= old_size)
+                return 0;
+
+        if (f->metrics.max_size > 0 &&
+            new_size > f->metrics.max_size)
+                return -E2BIG;
+
+        if (new_size > f->metrics.min_size &&
+            f->metrics.keep_free > 0) {
+                struct statvfs svfs;
+
+                if (fstatvfs(f->fd, &svfs) >= 0) {
+                        uint64_t available;
+
+                        available = svfs.f_bfree * svfs.f_bsize;
+
+                        if (available >= f->metrics.keep_free)
+                                available -= f->metrics.keep_free;
+                        else
+                                available = 0;
+
+                        if (new_size - old_size > available)
+                                return -E2BIG;
+                }
+        }
+
+        /* Note that the glibc fallocate() fallback is very
+           inefficient, hence we try to minimize the allocation area
+           as we can. */
+        if (posix_fallocate(f->fd, old_size, new_size - old_size) < 0)
+                return -errno;
+
+        if (fstat(f->fd, &f->last_stat) < 0)
+                return -errno;
+
+        f->header->arena_size = new_size - htole64(f->header->arena_offset);
+
+        return 0;
+}
+
+static int journal_file_map(
+                JournalFile *f,
+                uint64_t offset,
+                uint64_t size,
+                void **_window,
+                uint64_t *_woffset,
+                uint64_t *_wsize,
+                void **ret) {
+
+        uint64_t woffset, wsize;
+        void *window;
+
+        assert(f);
+        assert(size > 0);
+        assert(ret);
+
+        woffset = offset & ~((uint64_t) page_size() - 1ULL);
+        wsize = size + (offset - woffset);
+        wsize = PAGE_ALIGN(wsize);
+
+        /* Avoid SIGBUS on invalid accesses */
+        if (woffset + wsize > (uint64_t) PAGE_ALIGN(f->last_stat.st_size))
+                return -EADDRNOTAVAIL;
+
+        window = mmap(NULL, wsize, f->prot, MAP_SHARED, f->fd, woffset);
+        if (window == MAP_FAILED)
+                return -errno;
+
+        if (_window)
+                *_window = window;
+
+        if (_woffset)
+                *_woffset = woffset;
+
+        if (_wsize)
+                *_wsize = wsize;
+
+        *ret = (uint8_t*) window + (offset - woffset);
+
+        return 0;
+}
+
+static int journal_file_move_to(JournalFile *f, int wt, uint64_t offset, uint64_t size, void **ret) {
+        void *p;
+        uint64_t delta;
+        int r;
+        Window *w;
+
+        assert(f);
+        assert(ret);
+        assert(wt >= 0);
+        assert(wt < _WINDOW_MAX);
+
+        w = f->windows + wt;
+
+        if (_likely_(w->ptr &&
+                     w->offset <= offset &&
+                     w->offset + w->size >= offset + size)) {
+
+                *ret = (uint8_t*) w->ptr + (offset - w->offset);
+                return 0;
+        }
+
+        if (w->ptr) {
+                if (munmap(w->ptr, w->size) < 0)
+                        return -errno;
+
+                w->ptr = NULL;
+                w->size = w->offset = 0;
+        }
+
+        if (size < DEFAULT_WINDOW_SIZE) {
+                /* If the default window size is larger then what was
+                 * asked for extend the mapping a bit in the hope to
+                 * minimize needed remappings later on. We add half
+                 * the window space before and half behind the
+                 * requested mapping */
+
+                delta = PAGE_ALIGN((DEFAULT_WINDOW_SIZE - size) / 2);
+
+                if (offset < delta)
+                        delta = offset;
+
+                offset -= delta;
+                size += (DEFAULT_WINDOW_SIZE - delta);
+        } else
+                delta = 0;
+
+        if (offset > (uint64_t) f->last_stat.st_size)
+                return -EADDRNOTAVAIL;
+
+        if (offset + size > (uint64_t) f->last_stat.st_size)
+                size = PAGE_ALIGN((uint64_t) f->last_stat.st_size - offset);
+
+        if (size <= 0)
+                return -EADDRNOTAVAIL;
+
+        r = journal_file_map(f,
+                             offset, size,
+                             &w->ptr, &w->offset, &w->size,
+                             &p);
+
+        if (r < 0)
+                return r;
+
+        *ret = (uint8_t*) p + delta;
+        return 0;
+}
+
+static bool verify_hash(Object *o) {
+        uint64_t h1, h2;
+
+        assert(o);
+
+        if (o->object.type == OBJECT_DATA && !(o->object.flags & OBJECT_COMPRESSED)) {
+                h1 = le64toh(o->data.hash);
+                h2 = hash64(o->data.payload, le64toh(o->object.size) - offsetof(Object, data.payload));
+        } else if (o->object.type == OBJECT_FIELD) {
+                h1 = le64toh(o->field.hash);
+                h2 = hash64(o->field.payload, le64toh(o->object.size) - offsetof(Object, field.payload));
+        } else
+                return true;
+
+        return h1 == h2;
+}
+
+int journal_file_move_to_object(JournalFile *f, int type, uint64_t offset, Object **ret) {
+        int r;
+        void *t;
+        Object *o;
+        uint64_t s;
+
+        assert(f);
+        assert(ret);
+        assert(type < _OBJECT_TYPE_MAX);
+
+        r = journal_file_move_to(f, type >= 0 ? type : WINDOW_UNKNOWN, offset, sizeof(ObjectHeader), &t);
+        if (r < 0)
+                return r;
+
+        o = (Object*) t;
+        s = le64toh(o->object.size);
+
+        if (s < sizeof(ObjectHeader))
+                return -EBADMSG;
+
+        if (type >= 0 && o->object.type != type)
+                return -EBADMSG;
+
+        if (s > sizeof(ObjectHeader)) {
+                r = journal_file_move_to(f, o->object.type, offset, s, &t);
+                if (r < 0)
+                        return r;
+
+                o = (Object*) t;
+        }
+
+        if (!verify_hash(o))
+                return -EBADMSG;
+
+        *ret = o;
+        return 0;
+}
+
+static uint64_t journal_file_seqnum(JournalFile *f, uint64_t *seqnum) {
+        uint64_t r;
+
+        assert(f);
+
+        r = le64toh(f->header->seqnum) + 1;
+
+        if (seqnum) {
+                /* If an external seqnum counter was passed, we update
+                 * both the local and the external one, and set it to
+                 * the maximum of both */
+
+                if (*seqnum + 1 > r)
+                        r = *seqnum + 1;
+
+                *seqnum = r;
+        }
+
+        f->header->seqnum = htole64(r);
+
+        if (f->header->first_seqnum == 0)
+                f->header->first_seqnum = htole64(r);
+
+        return r;
+}
+
+static int journal_file_append_object(JournalFile *f, int type, uint64_t size, Object **ret, uint64_t *offset) {
+        int r;
+        uint64_t p;
+        Object *tail, *o;
+        void *t;
+
+        assert(f);
+        assert(size >= sizeof(ObjectHeader));
+        assert(offset);
+        assert(ret);
+
+        p = le64toh(f->header->tail_object_offset);
+        if (p == 0)
+                p = le64toh(f->header->arena_offset);
+        else {
+                r = journal_file_move_to_object(f, -1, p, &tail);
+                if (r < 0)
+                        return r;
+
+                p += ALIGN64(le64toh(tail->object.size));
+        }
+
+        r = journal_file_allocate(f, p, size);
+        if (r < 0)
+                return r;
+
+        r = journal_file_move_to(f, type, p, size, &t);
+        if (r < 0)
+                return r;
+
+        o = (Object*) t;
+
+        zero(o->object);
+        o->object.type = type;
+        o->object.size = htole64(size);
+
+        f->header->tail_object_offset = htole64(p);
+        f->header->n_objects = htole64(le64toh(f->header->n_objects) + 1);
+
+        *ret = o;
+        *offset = p;
+
+        return 0;
+}
+
+static int journal_file_setup_data_hash_table(JournalFile *f) {
+        uint64_t s, p;
+        Object *o;
+        int r;
+
+        assert(f);
+
+        s = DEFAULT_DATA_HASH_TABLE_SIZE;
+        r = journal_file_append_object(f,
+                                       OBJECT_DATA_HASH_TABLE,
+                                       offsetof(Object, hash_table.items) + s,
+                                       &o, &p);
+        if (r < 0)
+                return r;
+
+        memset(o->hash_table.items, 0, s);
+
+        f->header->data_hash_table_offset = htole64(p + offsetof(Object, hash_table.items));
+        f->header->data_hash_table_size = htole64(s);
+
+        return 0;
+}
+
+static int journal_file_setup_field_hash_table(JournalFile *f) {
+        uint64_t s, p;
+        Object *o;
+        int r;
+
+        assert(f);
+
+        s = DEFAULT_FIELD_HASH_TABLE_SIZE;
+        r = journal_file_append_object(f,
+                                       OBJECT_FIELD_HASH_TABLE,
+                                       offsetof(Object, hash_table.items) + s,
+                                       &o, &p);
+        if (r < 0)
+                return r;
+
+        memset(o->hash_table.items, 0, s);
+
+        f->header->field_hash_table_offset = htole64(p + offsetof(Object, hash_table.items));
+        f->header->field_hash_table_size = htole64(s);
+
+        return 0;
+}
+
+static int journal_file_map_data_hash_table(JournalFile *f) {
+        uint64_t s, p;
+        void *t;
+        int r;
+
+        assert(f);
+
+        p = le64toh(f->header->data_hash_table_offset);
+        s = le64toh(f->header->data_hash_table_size);
+
+        r = journal_file_move_to(f,
+                                 WINDOW_DATA_HASH_TABLE,
+                                 p, s,
+                                 &t);
+        if (r < 0)
+                return r;
+
+        f->data_hash_table = t;
+        return 0;
+}
+
+static int journal_file_map_field_hash_table(JournalFile *f) {
+        uint64_t s, p;
+        void *t;
+        int r;
+
+        assert(f);
+
+        p = le64toh(f->header->field_hash_table_offset);
+        s = le64toh(f->header->field_hash_table_size);
+
+        r = journal_file_move_to(f,
+                                 WINDOW_FIELD_HASH_TABLE,
+                                 p, s,
+                                 &t);
+        if (r < 0)
+                return r;
+
+        f->field_hash_table = t;
+        return 0;
+}
+
+static int journal_file_link_data(JournalFile *f, Object *o, uint64_t offset, uint64_t hash) {
+        uint64_t p, h;
+        int r;
+
+        assert(f);
+        assert(o);
+        assert(offset > 0);
+        assert(o->object.type == OBJECT_DATA);
+
+        o->data.next_hash_offset = o->data.next_field_offset = 0;
+        o->data.entry_offset = o->data.entry_array_offset = 0;
+        o->data.n_entries = 0;
+
+        h = hash % (le64toh(f->header->data_hash_table_size) / sizeof(HashItem));
+        p = le64toh(f->data_hash_table[h].head_hash_offset);
+        if (p == 0) {
+                /* Only entry in the hash table is easy */
+                f->data_hash_table[h].head_hash_offset = htole64(offset);
+        } else {
+                /* Temporarily move back to the previous data object,
+                 * to patch in pointer */
+
+                r = journal_file_move_to_object(f, OBJECT_DATA, p, &o);
+                if (r < 0)
+                        return r;
+
+                o->data.next_hash_offset = htole64(offset);
+
+                r = journal_file_move_to_object(f, OBJECT_DATA, offset, &o);
+                if (r < 0)
+                        return r;
+        }
+
+        f->data_hash_table[h].tail_hash_offset = htole64(offset);
+
+        return 0;
+}
+
+int journal_file_find_data_object_with_hash(
+                JournalFile *f,
+                const void *data, uint64_t size, uint64_t hash,
+                Object **ret, uint64_t *offset) {
+        uint64_t p, osize, h;
+        int r;
+
+        assert(f);
+        assert(data || size == 0);
+
+        osize = offsetof(Object, data.payload) + size;
+
+        if (f->header->data_hash_table_size == 0)
+                return -EBADMSG;
+
+        h = hash % (le64toh(f->header->data_hash_table_size) / sizeof(HashItem));
+        p = le64toh(f->data_hash_table[h].head_hash_offset);
+
+        while (p > 0) {
+                Object *o;
+
+                r = journal_file_move_to_object(f, OBJECT_DATA, p, &o);
+                if (r < 0)
+                        return r;
+
+                if (le64toh(o->data.hash) != hash)
+                        goto next;
+
+                if (o->object.flags & OBJECT_COMPRESSED) {
+#ifdef HAVE_XZ
+                        uint64_t l, rsize;
+
+                        l = le64toh(o->object.size);
+                        if (l <= offsetof(Object, data.payload))
+                                return -EBADMSG;
+
+                        l -= offsetof(Object, data.payload);
+
+                        if (!uncompress_blob(o->data.payload, l, &f->compress_buffer, &f->compress_buffer_size, &rsize))
+                                return -EBADMSG;
+
+                        if (rsize == size &&
+                            memcmp(f->compress_buffer, data, size) == 0) {
+
+                                if (ret)
+                                        *ret = o;
+
+                                if (offset)
+                                        *offset = p;
+
+                                return 1;
+                        }
+#else
+                        return -EPROTONOSUPPORT;
+#endif
+
+                } else if (le64toh(o->object.size) == osize &&
+                           memcmp(o->data.payload, data, size) == 0) {
+
+                        if (ret)
+                                *ret = o;
+
+                        if (offset)
+                                *offset = p;
+
+                        return 1;
+                }
+
+        next:
+                p = le64toh(o->data.next_hash_offset);
+        }
+
+        return 0;
+}
+
+int journal_file_find_data_object(
+                JournalFile *f,
+                const void *data, uint64_t size,
+                Object **ret, uint64_t *offset) {
+
+        uint64_t hash;
+
+        assert(f);
+        assert(data || size == 0);
+
+        hash = hash64(data, size);
+
+        return journal_file_find_data_object_with_hash(f,
+                                                       data, size, hash,
+                                                       ret, offset);
+}
+
+static int journal_file_append_data(JournalFile *f, const void *data, uint64_t size, Object **ret, uint64_t *offset) {
+        uint64_t hash, p;
+        uint64_t osize;
+        Object *o;
+        int r;
+        bool compressed = false;
+
+        assert(f);
+        assert(data || size == 0);
+
+        hash = hash64(data, size);
+
+        r = journal_file_find_data_object_with_hash(f, data, size, hash, &o, &p);
+        if (r < 0)
+                return r;
+        else if (r > 0) {
+
+                if (ret)
+                        *ret = o;
+
+                if (offset)
+                        *offset = p;
+
+                return 0;
+        }
+
+        osize = offsetof(Object, data.payload) + size;
+        r = journal_file_append_object(f, OBJECT_DATA, osize, &o, &p);
+        if (r < 0)
+                return r;
+
+        o->data.hash = htole64(hash);
+
+#ifdef HAVE_XZ
+        if (f->compress &&
+            size >= COMPRESSION_SIZE_THRESHOLD) {
+                uint64_t rsize;
+
+                compressed = compress_blob(data, size, o->data.payload, &rsize);
+
+                if (compressed) {
+                        o->object.size = htole64(offsetof(Object, data.payload) + rsize);
+                        o->object.flags |= OBJECT_COMPRESSED;
+
+                        f->header->incompatible_flags = htole32(le32toh(f->header->incompatible_flags) | HEADER_INCOMPATIBLE_COMPRESSED);
+
+                        log_debug("Compressed data object %lu -> %lu", (unsigned long) size, (unsigned long) rsize);
+                }
+        }
+#endif
+
+        if (!compressed)
+                memcpy(o->data.payload, data, size);
+
+        r = journal_file_link_data(f, o, p, hash);
+        if (r < 0)
+                return r;
+
+        if (ret)
+                *ret = o;
+
+        if (offset)
+                *offset = p;
+
+        return 0;
+}
+
+uint64_t journal_file_entry_n_items(Object *o) {
+        assert(o);
+        assert(o->object.type == htole64(OBJECT_ENTRY));
+
+        return (le64toh(o->object.size) - offsetof(Object, entry.items)) / sizeof(EntryItem);
+}
+
+static uint64_t journal_file_entry_array_n_items(Object *o) {
+        assert(o);
+        assert(o->object.type == htole64(OBJECT_ENTRY_ARRAY));
+
+        return (le64toh(o->object.size) - offsetof(Object, entry_array.items)) / sizeof(uint64_t);
+}
+
+static int link_entry_into_array(JournalFile *f,
+                                 uint64_t *first,
+                                 uint64_t *idx,
+                                 uint64_t p) {
+        int r;
+        uint64_t n = 0, ap = 0, q, i, a, hidx;
+        Object *o;
+
+        assert(f);
+        assert(first);
+        assert(idx);
+        assert(p > 0);
+
+        a = le64toh(*first);
+        i = hidx = le64toh(*idx);
+        while (a > 0) {
+
+                r = journal_file_move_to_object(f, OBJECT_ENTRY_ARRAY, a, &o);
+                if (r < 0)
+                        return r;
+
+                n = journal_file_entry_array_n_items(o);
+                if (i < n) {
+                        o->entry_array.items[i] = htole64(p);
+                        *idx = htole64(hidx + 1);
+                        return 0;
+                }
+
+                i -= n;
+                ap = a;
+                a = le64toh(o->entry_array.next_entry_array_offset);
+        }
+
+        if (hidx > n)
+                n = (hidx+1) * 2;
+        else
+                n = n * 2;
+
+        if (n < 4)
+                n = 4;
+
+        r = journal_file_append_object(f, OBJECT_ENTRY_ARRAY,
+                                       offsetof(Object, entry_array.items) + n * sizeof(uint64_t),
+                                       &o, &q);
+        if (r < 0)
+                return r;
+
+        o->entry_array.items[i] = htole64(p);
+
+        if (ap == 0)
+                *first = q;
+        else {
+                r = journal_file_move_to_object(f, OBJECT_ENTRY_ARRAY, ap, &o);
+                if (r < 0)
+                        return r;
+
+                o->entry_array.next_entry_array_offset = htole64(q);
+        }
+
+        *idx = htole64(hidx + 1);
+
+        return 0;
+}
+
+static int link_entry_into_array_plus_one(JournalFile *f,
+                                          uint64_t *extra,
+                                          uint64_t *first,
+                                          uint64_t *idx,
+                                          uint64_t p) {
+
+        int r;
+
+        assert(f);
+        assert(extra);
+        assert(first);
+        assert(idx);
+        assert(p > 0);
+
+        if (*idx == 0)
+                *extra = htole64(p);
+        else {
+                uint64_t i;
+
+                i = le64toh(*idx) - 1;
+                r = link_entry_into_array(f, first, &i, p);
+                if (r < 0)
+                        return r;
+        }
+
+        *idx = htole64(le64toh(*idx) + 1);
+        return 0;
+}
+
+static int journal_file_link_entry_item(JournalFile *f, Object *o, uint64_t offset, uint64_t i) {
+        uint64_t p;
+        int r;
+        assert(f);
+        assert(o);
+        assert(offset > 0);
+
+        p = le64toh(o->entry.items[i].object_offset);
+        if (p == 0)
+                return -EINVAL;
+
+        r = journal_file_move_to_object(f, OBJECT_DATA, p, &o);
+        if (r < 0)
+                return r;
+
+        return link_entry_into_array_plus_one(f,
+                                              &o->data.entry_offset,
+                                              &o->data.entry_array_offset,
+                                              &o->data.n_entries,
+                                              offset);
+}
+
+static int journal_file_link_entry(JournalFile *f, Object *o, uint64_t offset) {
+        uint64_t n, i;
+        int r;
+
+        assert(f);
+        assert(o);
+        assert(offset > 0);
+        assert(o->object.type == OBJECT_ENTRY);
+
+        /* Link up the entry itself */
+        r = link_entry_into_array(f,
+                                  &f->header->entry_array_offset,
+                                  &f->header->n_entries,
+                                  offset);
+        if (r < 0)
+                return r;
+
+        log_error("=> %s seqnr=%lu n_entries=%lu", f->path, (unsigned long) o->entry.seqnum, (unsigned long) f->header->n_entries);
+
+        if (f->header->head_entry_realtime == 0)
+                f->header->head_entry_realtime = o->entry.realtime;
+
+        f->header->tail_entry_realtime = o->entry.realtime;
+        f->header->tail_entry_monotonic = o->entry.monotonic;
+
+        f->tail_entry_monotonic_valid = true;
+
+        /* Link up the items */
+        n = journal_file_entry_n_items(o);
+        for (i = 0; i < n; i++) {
+                r = journal_file_link_entry_item(f, o, offset, i);
+                if (r < 0)
+                        return r;
+        }
+
+        return 0;
+}
+
+static int journal_file_append_entry_internal(
+                JournalFile *f,
+                const dual_timestamp *ts,
+                uint64_t xor_hash,
+                const EntryItem items[], unsigned n_items,
+                uint64_t *seqnum,
+                Object **ret, uint64_t *offset) {
+        uint64_t np;
+        uint64_t osize;
+        Object *o;
+        int r;
+
+        assert(f);
+        assert(items || n_items == 0);
+        assert(ts);
+
+        osize = offsetof(Object, entry.items) + (n_items * sizeof(EntryItem));
+
+        r = journal_file_append_object(f, OBJECT_ENTRY, osize, &o, &np);
+        if (r < 0)
+                return r;
+
+        o->entry.seqnum = htole64(journal_file_seqnum(f, seqnum));
+        memcpy(o->entry.items, items, n_items * sizeof(EntryItem));
+        o->entry.realtime = htole64(ts->realtime);
+        o->entry.monotonic = htole64(ts->monotonic);
+        o->entry.xor_hash = htole64(xor_hash);
+        o->entry.boot_id = f->header->boot_id;
+
+        r = journal_file_link_entry(f, o, np);
+        if (r < 0)
+                return r;
+
+        if (ret)
+                *ret = o;
+
+        if (offset)
+                *offset = np;
+
+        return 0;
+}
+
+void journal_file_post_change(JournalFile *f) {
+        assert(f);
+
+        /* inotify() does not receive IN_MODIFY events from file
+         * accesses done via mmap(). After each access we hence
+         * trigger IN_MODIFY by truncating the journal file to its
+         * current size which triggers IN_MODIFY. */
+
+        __sync_synchronize();
+
+        if (ftruncate(f->fd, f->last_stat.st_size) < 0)
+                log_error("Failed to to truncate file to its own size: %m");
+}
+
+int journal_file_append_entry(JournalFile *f, const dual_timestamp *ts, const struct iovec iovec[], unsigned n_iovec, uint64_t *seqnum, Object **ret, uint64_t *offset) {
+        unsigned i;
+        EntryItem *items;
+        int r;
+        uint64_t xor_hash = 0;
+        struct dual_timestamp _ts;
+
+        assert(f);
+        assert(iovec || n_iovec == 0);
+
+        if (!f->writable)
+                return -EPERM;
+
+        if (!ts) {
+                dual_timestamp_get(&_ts);
+                ts = &_ts;
+        }
+
+        if (f->tail_entry_monotonic_valid &&
+            ts->monotonic < le64toh(f->header->tail_entry_monotonic))
+                return -EINVAL;
+
+        if (ts->realtime < le64toh(f->header->tail_entry_realtime))
+                return -EINVAL;
+
+        items = alloca(sizeof(EntryItem) * n_iovec);
+
+        for (i = 0; i < n_iovec; i++) {
+                uint64_t p;
+                Object *o;
+
+                r = journal_file_append_data(f, iovec[i].iov_base, iovec[i].iov_len, &o, &p);
+                if (r < 0)
+                        return r;
+
+                xor_hash ^= le64toh(o->data.hash);
+                items[i].object_offset = htole64(p);
+                items[i].hash = o->data.hash;
+        }
+
+        r = journal_file_append_entry_internal(f, ts, xor_hash, items, n_iovec, seqnum, ret, offset);
+
+        journal_file_post_change(f);
+
+        return r;
+}
+
+static int generic_array_get(JournalFile *f,
+                             uint64_t first,
+                             uint64_t i,
+                             Object **ret, uint64_t *offset) {
+
+        Object *o;
+        uint64_t p, a;
+        int r;
+
+        assert(f);
+
+        a = first;
+        while (a > 0) {
+                uint64_t n;
+
+                r = journal_file_move_to_object(f, OBJECT_ENTRY_ARRAY, a, &o);
+                if (r < 0)
+                        return r;
+
+                n = journal_file_entry_array_n_items(o);
+                if (i < n) {
+                        p = le64toh(o->entry_array.items[i]);
+                        break;
+                }
+
+                i -= n;
+                a = le64toh(o->entry_array.next_entry_array_offset);
+        }
+
+        if (a <= 0 || p <= 0)
+                return 0;
+
+        r = journal_file_move_to_object(f, OBJECT_ENTRY, p, &o);
+        if (r < 0)
+                return r;
+
+        if (ret)
+                *ret = o;
+
+        if (offset)
+                *offset = p;
+
+        return 1;
+}
+
+static int generic_array_get_plus_one(JournalFile *f,
+                                      uint64_t extra,
+                                      uint64_t first,
+                                      uint64_t i,
+                                      Object **ret, uint64_t *offset) {
+
+        Object *o;
+
+        assert(f);
+
+        if (i == 0) {
+                int r;
+
+                r = journal_file_move_to_object(f, OBJECT_ENTRY, extra, &o);
+                if (r < 0)
+                        return r;
+
+                if (ret)
+                        *ret = o;
+
+                if (offset)
+                        *offset = extra;
+
+                return 1;
+        }
+
+        return generic_array_get(f, first, i-1, ret, offset);
+}
+
+enum {
+        TEST_FOUND,
+        TEST_LEFT,
+        TEST_RIGHT
+};
+
+static int generic_array_bisect(JournalFile *f,
+                                uint64_t first,
+                                uint64_t n,
+                                uint64_t needle,
+                                int (*test_object)(JournalFile *f, uint64_t p, uint64_t needle),
+                                direction_t direction,
+                                Object **ret,
+                                uint64_t *offset,
+                                uint64_t *idx) {
+
+        uint64_t a, p, t = 0, i = 0, last_p = 0;
+        bool subtract_one = false;
+        Object *o, *array = NULL;
+        int r;
+
+        assert(f);
+        assert(test_object);
+
+        a = first;
+        while (a > 0) {
+                uint64_t left, right, k, lp;
+
+                r = journal_file_move_to_object(f, OBJECT_ENTRY_ARRAY, a, &array);
+                if (r < 0)
+                        return r;
+
+                k = journal_file_entry_array_n_items(array);
+                right = MIN(k, n);
+                if (right <= 0)
+                        return 0;
+
+                i = right - 1;
+                lp = p = le64toh(array->entry_array.items[i]);
+                if (p <= 0)
+                        return -EBADMSG;
+
+                r = test_object(f, p, needle);
+                if (r < 0)
+                        return r;
+
+                if (r == TEST_FOUND)
+                        r = direction == DIRECTION_DOWN ? TEST_RIGHT : TEST_LEFT;
+
+                if (r == TEST_RIGHT) {
+                        left = 0;
+                        right -= 1;
+                        for (;;) {
+                                if (left == right) {
+                                        if (direction == DIRECTION_UP)
+                                                subtract_one = true;
+
+                                        i = left;
+                                        goto found;
+                                }
+
+                                assert(left < right);
+
+                                i = (left + right) / 2;
+                                p = le64toh(array->entry_array.items[i]);
+                                if (p <= 0)
+                                        return -EBADMSG;
+
+                                r = test_object(f, p, needle);
+                                if (r < 0)
+                                        return r;
+
+                                if (r == TEST_FOUND)
+                                        r = direction == DIRECTION_DOWN ? TEST_RIGHT : TEST_LEFT;
+
+                                if (r == TEST_RIGHT)
+                                        right = i;
+                                else
+                                        left = i + 1;
+                        }
+                }
+
+                if (k > n)
+                        return 0;
+
+                last_p = lp;
+
+                n -= k;
+                t += k;
+                a = le64toh(array->entry_array.next_entry_array_offset);
+        }
+
+        return 0;
+
+found:
+        if (subtract_one && t == 0 && i == 0)
+                return 0;
+
+        if (subtract_one && i == 0)
+                p = last_p;
+        else if (subtract_one)
+                p = le64toh(array->entry_array.items[i-1]);
+        else
+                p = le64toh(array->entry_array.items[i]);
+
+        r = journal_file_move_to_object(f, OBJECT_ENTRY, p, &o);
+        if (r < 0)
+                return r;
+
+        if (ret)
+                *ret = o;
+
+        if (offset)
+                *offset = p;
+
+        if (idx)
+                *idx = t + i - (subtract_one ? 1 : 0);
+
+        return 1;
+}
+
+static int generic_array_bisect_plus_one(JournalFile *f,
+                                         uint64_t extra,
+                                         uint64_t first,
+                                         uint64_t n,
+                                         uint64_t needle,
+                                         int (*test_object)(JournalFile *f, uint64_t p, uint64_t needle),
+                                         direction_t direction,
+                                         Object **ret,
+                                         uint64_t *offset,
+                                         uint64_t *idx) {
+
+        int r;
+
+        assert(f);
+        assert(test_object);
+
+        if (n <= 0)
+                return 0;
+
+        /* This bisects the array in object 'first', but first checks
+         * an extra  */
+        r = test_object(f, extra, needle);
+        if (r < 0)
+                return r;
+        else if (r == TEST_FOUND) {
+                Object *o;
+
+                r = journal_file_move_to_object(f, OBJECT_ENTRY, extra, &o);
+                if (r < 0)
+                        return r;
+
+                if (ret)
+                        *ret = o;
+
+                if (offset)
+                        *offset = extra;
+
+                if (idx)
+                        *idx = 0;
+
+                return 1;
+        } else if (r == TEST_RIGHT)
+                return 0;
+
+        r = generic_array_bisect(f, first, n-1, needle, test_object, direction, ret, offset, idx);
+
+        if (r > 0)
+                (*idx) ++;
+
+        return r;
+}
+
+static int test_object_seqnum(JournalFile *f, uint64_t p, uint64_t needle) {
+        Object *o;
+        int r;
+
+        assert(f);
+        assert(p > 0);
+
+        r = journal_file_move_to_object(f, OBJECT_ENTRY, p, &o);
+        if (r < 0)
+                return r;
+
+        if (le64toh(o->entry.seqnum) == needle)
+                return TEST_FOUND;
+        else if (le64toh(o->entry.seqnum) < needle)
+                return TEST_LEFT;
+        else
+                return TEST_RIGHT;
+}
+
+int journal_file_move_to_entry_by_seqnum(
+                JournalFile *f,
+                uint64_t seqnum,
+                direction_t direction,
+                Object **ret,
+                uint64_t *offset) {
+
+        return generic_array_bisect(f,
+                                    le64toh(f->header->entry_array_offset),
+                                    le64toh(f->header->n_entries),
+                                    seqnum,
+                                    test_object_seqnum,
+                                    direction,
+                                    ret, offset, NULL);
+}
+
+static int test_object_realtime(JournalFile *f, uint64_t p, uint64_t needle) {
+        Object *o;
+        int r;
+
+        assert(f);
+        assert(p > 0);
+
+        r = journal_file_move_to_object(f, OBJECT_ENTRY, p, &o);
+        if (r < 0)
+                return r;
+
+        if (le64toh(o->entry.realtime) == needle)
+                return TEST_FOUND;
+        else if (le64toh(o->entry.realtime) < needle)
+                return TEST_LEFT;
+        else
+                return TEST_RIGHT;
+}
+
+int journal_file_move_to_entry_by_realtime(
+                JournalFile *f,
+                uint64_t realtime,
+                direction_t direction,
+                Object **ret,
+                uint64_t *offset) {
+
+        return generic_array_bisect(f,
+                                    le64toh(f->header->entry_array_offset),
+                                    le64toh(f->header->n_entries),
+                                    realtime,
+                                    test_object_realtime,
+                                    direction,
+                                    ret, offset, NULL);
+}
+
+static int test_object_monotonic(JournalFile *f, uint64_t p, uint64_t needle) {
+        Object *o;
+        int r;
+
+        assert(f);
+        assert(p > 0);
+
+        r = journal_file_move_to_object(f, OBJECT_ENTRY, p, &o);
+        if (r < 0)
+                return r;
+
+        if (le64toh(o->entry.monotonic) == needle)
+                return TEST_FOUND;
+        else if (le64toh(o->entry.monotonic) < needle)
+                return TEST_LEFT;
+        else
+                return TEST_RIGHT;
+}
+
+int journal_file_move_to_entry_by_monotonic(
+                JournalFile *f,
+                sd_id128_t boot_id,
+                uint64_t monotonic,
+                direction_t direction,
+                Object **ret,
+                uint64_t *offset) {
+
+        char t[8+32+1] = "_BOOT_ID=";
+        Object *o;
+        int r;
+
+        sd_id128_to_string(boot_id, t + 8);
+
+        r = journal_file_find_data_object(f, t, strlen(t), &o, NULL);
+        if (r < 0)
+                return r;
+        else if (r == 0)
+                return -ENOENT;
+
+        return generic_array_bisect_plus_one(f,
+                                             le64toh(o->data.entry_offset),
+                                             le64toh(o->data.entry_array_offset),
+                                             le64toh(o->data.n_entries),
+                                             monotonic,
+                                             test_object_monotonic,
+                                             direction,
+                                             ret, offset, NULL);
+}
+
+static int test_object_offset(JournalFile *f, uint64_t p, uint64_t needle) {
+        assert(f);
+        assert(p > 0);
+
+        if (p == needle)
+                return TEST_FOUND;
+        else if (p < needle)
+                return TEST_LEFT;
+        else
+                return TEST_RIGHT;
+}
+
+int journal_file_next_entry(
+                JournalFile *f,
+                Object *o, uint64_t p,
+                direction_t direction,
+                Object **ret, uint64_t *offset) {
+
+        uint64_t i, n;
+        int r;
+
+        assert(f);
+        assert(p > 0 || !o);
+
+        n = le64toh(f->header->n_entries);
+        if (n <= 0)
+                return 0;
+
+        if (!o)
+                i = direction == DIRECTION_DOWN ? 0 : n - 1;
+        else {
+                if (o->object.type != OBJECT_ENTRY)
+                        return -EINVAL;
+
+                r = generic_array_bisect(f,
+                                         le64toh(f->header->entry_array_offset),
+                                         le64toh(f->header->n_entries),
+                                         p,
+                                         test_object_offset,
+                                         DIRECTION_DOWN,
+                                         NULL, NULL,
+                                         &i);
+                if (r <= 0)
+                        return r;
+
+                if (direction == DIRECTION_DOWN) {
+                        if (i >= n - 1)
+                                return 0;
+
+                        i++;
+                } else {
+                        if (i <= 0)
+                                return 0;
+
+                        i--;
+                }
+        }
+
+        /* And jump to it */
+        return generic_array_get(f,
+                                 le64toh(f->header->entry_array_offset),
+                                 i,
+                                 ret, offset);
+}
+
+int journal_file_skip_entry(
+                JournalFile *f,
+                Object *o, uint64_t p,
+                int64_t skip,
+                Object **ret, uint64_t *offset) {
+
+        uint64_t i, n;
+        int r;
+
+        assert(f);
+        assert(o);
+        assert(p > 0);
+
+        if (o->object.type != OBJECT_ENTRY)
+                return -EINVAL;
+
+        r = generic_array_bisect(f,
+                                 le64toh(f->header->entry_array_offset),
+                                 le64toh(f->header->n_entries),
+                                 p,
+                                 test_object_offset,
+                                 DIRECTION_DOWN,
+                                 NULL, NULL,
+                                 &i);
+        if (r <= 0)
+                return r;
+
+        /* Calculate new index */
+        if (skip < 0) {
+                if ((uint64_t) -skip >= i)
+                        i = 0;
+                else
+                        i = i - (uint64_t) -skip;
+        } else
+                i  += (uint64_t) skip;
+
+        n = le64toh(f->header->n_entries);
+        if (n <= 0)
+                return -EBADMSG;
+
+        if (i >= n)
+                i = n-1;
+
+        return generic_array_get(f,
+                                 le64toh(f->header->entry_array_offset),
+                                 i,
+                                 ret, offset);
+}
+
+int journal_file_next_entry_for_data(
+                JournalFile *f,
+                Object *o, uint64_t p,
+                uint64_t data_offset,
+                direction_t direction,
+                Object **ret, uint64_t *offset) {
+
+        uint64_t n, i;
+        int r;
+        Object *d;
+
+        assert(f);
+        assert(p > 0 || !o);
+
+        r = journal_file_move_to_object(f, OBJECT_DATA, data_offset, &d);
+        if (r < 0)
+                return r;
+
+        n = le64toh(d->data.n_entries);
+        if (n <= 0)
+                return n;
+
+        if (!o)
+                i = direction == DIRECTION_DOWN ? 0 : n - 1;
+        else {
+                if (o->object.type != OBJECT_ENTRY)
+                        return -EINVAL;
+
+                r = generic_array_bisect_plus_one(f,
+                                                  le64toh(d->data.entry_offset),
+                                                  le64toh(d->data.entry_array_offset),
+                                                  le64toh(d->data.n_entries),
+                                                  p,
+                                                  test_object_offset,
+                                                  DIRECTION_DOWN,
+                                                  NULL, NULL,
+                                                  &i);
+
+                if (r <= 0)
+                        return r;
+
+                if (direction == DIRECTION_DOWN) {
+                        if (i >= n - 1)
+                                return 0;
+
+                        i++;
+                } else {
+                        if (i <= 0)
+                                return 0;
+
+                        i--;
+                }
+
+        }
+
+        return generic_array_get_plus_one(f,
+                                          le64toh(d->data.entry_offset),
+                                          le64toh(d->data.entry_array_offset),
+                                          i,
+                                          ret, offset);
+}
+
+int journal_file_move_to_entry_by_seqnum_for_data(
+                JournalFile *f,
+                uint64_t data_offset,
+                uint64_t seqnum,
+                direction_t direction,
+                Object **ret, uint64_t *offset) {
+
+        Object *d;
+        int r;
+
+        r = journal_file_move_to_object(f, OBJECT_DATA, data_offset, &d);
+        if (r <= 0)
+                return r;
+
+        return generic_array_bisect_plus_one(f,
+                                             le64toh(d->data.entry_offset),
+                                             le64toh(d->data.entry_array_offset),
+                                             le64toh(d->data.n_entries),
+                                             seqnum,
+                                             test_object_seqnum,
+                                             direction,
+                                             ret, offset, NULL);
+}
+
+int journal_file_move_to_entry_by_realtime_for_data(
+                JournalFile *f,
+                uint64_t data_offset,
+                uint64_t realtime,
+                direction_t direction,
+                Object **ret, uint64_t *offset) {
+
+        Object *d;
+        int r;
+
+        r = journal_file_move_to_object(f, OBJECT_DATA, data_offset, &d);
+        if (r <= 0)
+                return r;
+
+        return generic_array_bisect_plus_one(f,
+                                             le64toh(d->data.entry_offset),
+                                             le64toh(d->data.entry_array_offset),
+                                             le64toh(d->data.n_entries),
+                                             realtime,
+                                             test_object_realtime,
+                                             direction,
+                                             ret, offset, NULL);
+}
+
+void journal_file_dump(JournalFile *f) {
+        char a[33], b[33], c[33];
+        Object *o;
+        int r;
+        uint64_t p;
+
+        assert(f);
+
+        printf("File Path: %s\n"
+               "File ID: %s\n"
+               "Machine ID: %s\n"
+               "Boot ID: %s\n"
+               "Arena size: %llu\n"
+               "Objects: %lu\n"
+               "Entries: %lu\n",
+               f->path,
+               sd_id128_to_string(f->header->file_id, a),
+               sd_id128_to_string(f->header->machine_id, b),
+               sd_id128_to_string(f->header->boot_id, c),
+               (unsigned long long) le64toh(f->header->arena_size),
+               (unsigned long) le64toh(f->header->n_objects),
+               (unsigned long) le64toh(f->header->n_entries));
+
+        p = le64toh(f->header->arena_offset);
+        while (p != 0) {
+                r = journal_file_move_to_object(f, -1, p, &o);
+                if (r < 0)
+                        goto fail;
+
+                switch (o->object.type) {
+
+                case OBJECT_UNUSED:
+                        printf("Type: OBJECT_UNUSED\n");
+                        break;
+
+                case OBJECT_DATA:
+                        printf("Type: OBJECT_DATA\n");
+                        break;
+
+                case OBJECT_ENTRY:
+                        printf("Type: OBJECT_ENTRY %llu %llu %llu\n",
+                               (unsigned long long) le64toh(o->entry.seqnum),
+                               (unsigned long long) le64toh(o->entry.monotonic),
+                               (unsigned long long) le64toh(o->entry.realtime));
+                        break;
+
+                case OBJECT_FIELD_HASH_TABLE:
+                        printf("Type: OBJECT_FIELD_HASH_TABLE\n");
+                        break;
+
+                case OBJECT_DATA_HASH_TABLE:
+                        printf("Type: OBJECT_DATA_HASH_TABLE\n");
+                        break;
+
+                case OBJECT_ENTRY_ARRAY:
+                        printf("Type: OBJECT_ENTRY_ARRAY\n");
+                        break;
+                }
+
+                if (o->object.flags & OBJECT_COMPRESSED)
+                        printf("Flags: COMPRESSED\n");
+
+                if (p == le64toh(f->header->tail_object_offset))
+                        p = 0;
+                else
+                        p = p + ALIGN64(le64toh(o->object.size));
+        }
+
+        return;
+fail:
+        log_error("File corrupt");
+}
+
+int journal_file_open(
+                const char *fname,
+                int flags,
+                mode_t mode,
+                JournalFile *template,
+                JournalFile **ret) {
+
+        JournalFile *f;
+        int r;
+        bool newly_created = false;
+
+        assert(fname);
+
+        if ((flags & O_ACCMODE) != O_RDONLY &&
+            (flags & O_ACCMODE) != O_RDWR)
+                return -EINVAL;
+
+        f = new0(JournalFile, 1);
+        if (!f)
+                return -ENOMEM;
+
+        f->fd = -1;
+        f->flags = flags;
+        f->mode = mode;
+        f->writable = (flags & O_ACCMODE) != O_RDONLY;
+        f->prot = prot_from_flags(flags);
+
+        f->metrics.max_size = DEFAULT_MAX_SIZE;
+        f->metrics.min_size = DEFAULT_MIN_SIZE;
+        f->metrics.keep_free = DEFAULT_KEEP_FREE;
+
+        f->path = strdup(fname);
+        if (!f->path) {
+                r = -ENOMEM;
+                goto fail;
+        }
+
+        f->fd = open(f->path, f->flags|O_CLOEXEC, f->mode);
+        if (f->fd < 0) {
+                r = -errno;
+                goto fail;
+        }
+
+        if (fstat(f->fd, &f->last_stat) < 0) {
+                r = -errno;
+                goto fail;
+        }
+
+        if (f->last_stat.st_size == 0 && f->writable) {
+                newly_created = true;
+
+                r = journal_file_init_header(f, template);
+                if (r < 0)
+                        goto fail;
+
+                if (fstat(f->fd, &f->last_stat) < 0) {
+                        r = -errno;
+                        goto fail;
+                }
+        }
+
+        if (f->last_stat.st_size < (off_t) sizeof(Header)) {
+                r = -EIO;
+                goto fail;
+        }
+
+        f->header = mmap(NULL, PAGE_ALIGN(sizeof(Header)), prot_from_flags(flags), MAP_SHARED, f->fd, 0);
+        if (f->header == MAP_FAILED) {
+                f->header = NULL;
+                r = -errno;
+                goto fail;
+        }
+
+        if (!newly_created) {
+                r = journal_file_verify_header(f);
+                if (r < 0)
+                        goto fail;
+        }
+
+        if (f->writable) {
+                r = journal_file_refresh_header(f);
+                if (r < 0)
+                        goto fail;
+        }
+
+        if (newly_created) {
+
+                r = journal_file_setup_field_hash_table(f);
+                if (r < 0)
+                        goto fail;
+
+                r = journal_file_setup_data_hash_table(f);
+                if (r < 0)
+                        goto fail;
+        }
+
+        r = journal_file_map_field_hash_table(f);
+        if (r < 0)
+                goto fail;
+
+        r = journal_file_map_data_hash_table(f);
+        if (r < 0)
+                goto fail;
+
+        if (ret)
+                *ret = f;
+
+        return 0;
+
+fail:
+        journal_file_close(f);
+
+        return r;
+}
+
+int journal_file_rotate(JournalFile **f) {
+        char *p;
+        size_t l;
+        JournalFile *old_file, *new_file = NULL;
+        int r;
+
+        assert(f);
+        assert(*f);
+
+        old_file = *f;
+
+        if (!old_file->writable)
+                return -EINVAL;
+
+        if (!endswith(old_file->path, ".journal"))
+                return -EINVAL;
+
+        l = strlen(old_file->path);
+
+        p = new(char, l + 1 + 16 + 1 + 32 + 1 + 16 + 1);
+        if (!p)
+                return -ENOMEM;
+
+        memcpy(p, old_file->path, l - 8);
+        p[l-8] = '@';
+        sd_id128_to_string(old_file->header->seqnum_id, p + l - 8 + 1);
+        snprintf(p + l - 8 + 1 + 32, 1 + 16 + 1 + 16 + 8 + 1,
+                 "-%016llx-%016llx.journal",
+                 (unsigned long long) le64toh((*f)->header->seqnum),
+                 (unsigned long long) le64toh((*f)->header->tail_entry_realtime));
+
+        r = rename(old_file->path, p);
+        free(p);
+
+        if (r < 0)
+                return -errno;
+
+        old_file->header->state = le32toh(STATE_ARCHIVED);
+
+        r = journal_file_open(old_file->path, old_file->flags, old_file->mode, old_file, &new_file);
+        journal_file_close(old_file);
+
+        *f = new_file;
+        return r;
+}
+
+struct vacuum_info {
+        off_t usage;
+        char *filename;
+
+        uint64_t realtime;
+        sd_id128_t seqnum_id;
+        uint64_t seqnum;
+};
+
+static int vacuum_compare(const void *_a, const void *_b) {
+        const struct vacuum_info *a, *b;
+
+        a = _a;
+        b = _b;
+
+        if (sd_id128_equal(a->seqnum_id, b->seqnum_id)) {
+                if (a->seqnum < b->seqnum)
+                        return -1;
+                else if (a->seqnum > b->seqnum)
+                        return 1;
+                else
+                        return 0;
+        }
+
+        if (a->realtime < b->realtime)
+                return -1;
+        else if (a->realtime > b->realtime)
+                return 1;
+        else
+                return memcmp(&a->seqnum_id, &b->seqnum_id, 16);
+}
+
+int journal_directory_vacuum(const char *directory, uint64_t max_use, uint64_t min_free) {
+        DIR *d;
+        int r = 0;
+        struct vacuum_info *list = NULL;
+        unsigned n_list = 0, n_allocated = 0, i;
+        uint64_t sum = 0;
+
+        assert(directory);
+
+        if (max_use <= 0)
+                max_use = DEFAULT_MAX_USE;
+
+        d = opendir(directory);
+        if (!d)
+                return -errno;
+
+        for (;;) {
+                int k;
+                struct dirent buf, *de;
+                size_t q;
+                struct stat st;
+                char *p;
+                unsigned long long seqnum, realtime;
+                sd_id128_t seqnum_id;
+
+                k = readdir_r(d, &buf, &de);
+                if (k != 0) {
+                        r = -k;
+                        goto finish;
+                }
+
+                if (!de)
+                        break;
+
+                if (!dirent_is_file_with_suffix(de, ".journal"))
+                        continue;
+
+                q = strlen(de->d_name);
+
+                if (q < 1 + 32 + 1 + 16 + 1 + 16 + 8)
+                        continue;
+
+                if (de->d_name[q-8-16-1] != '-' ||
+                    de->d_name[q-8-16-1-16-1] != '-' ||
+                    de->d_name[q-8-16-1-16-1-32-1] != '@')
+                        continue;
+
+                if (fstatat(dirfd(d), de->d_name, &st, AT_SYMLINK_NOFOLLOW) < 0)
+                        continue;
+
+                if (!S_ISREG(st.st_mode))
+                        continue;
+
+                p = strdup(de->d_name);
+                if (!p) {
+                        r = -ENOMEM;
+                        goto finish;
+                }
+
+                de->d_name[q-8-16-1-16-1] = 0;
+                if (sd_id128_from_string(de->d_name + q-8-16-1-16-1-32, &seqnum_id) < 0) {
+                        free(p);
+                        continue;
+                }
+
+                if (sscanf(de->d_name + q-8-16-1-16, "%16llx-%16llx.journal", &seqnum, &realtime) != 2) {
+                        free(p);
+                        continue;
+                }
+
+                if (n_list >= n_allocated) {
+                        struct vacuum_info *j;
+
+                        n_allocated = MAX(n_allocated * 2U, 8U);
+                        j = realloc(list, n_allocated * sizeof(struct vacuum_info));
+                        if (!j) {
+                                free(p);
+                                r = -ENOMEM;
+                                goto finish;
+                        }
+
+                        list = j;
+                }
+
+                list[n_list].filename = p;
+                list[n_list].usage = (uint64_t) st.st_blksize * (uint64_t) st.st_blocks;
+                list[n_list].seqnum = seqnum;
+                list[n_list].realtime = realtime;
+                list[n_list].seqnum_id = seqnum_id;
+
+                sum += list[n_list].usage;
+
+                n_list ++;
+        }
+
+        qsort(list, n_list, sizeof(struct vacuum_info), vacuum_compare);
+
+        for(i = 0; i < n_list; i++) {
+                struct statvfs ss;
+
+                if (fstatvfs(dirfd(d), &ss) < 0) {
+                        r = -errno;
+                        goto finish;
+                }
+
+                if (sum <= max_use &&
+                    (uint64_t) ss.f_bavail * (uint64_t) ss.f_bsize >= min_free)
+                        break;
+
+                if (unlinkat(dirfd(d), list[i].filename, 0) >= 0) {
+                        log_debug("Deleted archived journal %s/%s.", directory, list[i].filename);
+                        sum -= list[i].usage;
+                } else if (errno != ENOENT)
+                        log_warning("Failed to delete %s/%s: %m", directory, list[i].filename);
+        }
+
+finish:
+        for (i = 0; i < n_list; i++)
+                free(list[i].filename);
+
+        free(list);
+
+        if (d)
+                closedir(d);
+
+        return r;
+}
+
+int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint64_t p, uint64_t *seqnum, Object **ret, uint64_t *offset) {
+        uint64_t i, n;
+        uint64_t q, xor_hash = 0;
+        int r;
+        EntryItem *items;
+        dual_timestamp ts;
+
+        assert(from);
+        assert(to);
+        assert(o);
+        assert(p);
+
+        if (!to->writable)
+                return -EPERM;
+
+        ts.monotonic = le64toh(o->entry.monotonic);
+        ts.realtime = le64toh(o->entry.realtime);
+
+        if (to->tail_entry_monotonic_valid &&
+            ts.monotonic < le64toh(to->header->tail_entry_monotonic))
+                return -EINVAL;
+
+        if (ts.realtime < le64toh(to->header->tail_entry_realtime))
+                return -EINVAL;
+
+        n = journal_file_entry_n_items(o);
+        items = alloca(sizeof(EntryItem) * n);
+
+        for (i = 0; i < n; i++) {
+                uint64_t le_hash, l, h;
+                size_t t;
+                void *data;
+                Object *u;
+
+                q = le64toh(o->entry.items[i].object_offset);
+                le_hash = o->entry.items[i].hash;
+
+                r = journal_file_move_to_object(from, OBJECT_DATA, q, &o);
+                if (r < 0)
+                        return r;
+
+                if (le_hash != o->data.hash)
+                        return -EBADMSG;
+
+                l = le64toh(o->object.size) - offsetof(Object, data.payload);
+                t = (size_t) l;
+
+                /* We hit the limit on 32bit machines */
+                if ((uint64_t) t != l)
+                        return -E2BIG;
+
+                if (o->object.flags & OBJECT_COMPRESSED) {
+#ifdef HAVE_XZ
+                        uint64_t rsize;
+
+                        if (!uncompress_blob(o->data.payload, l, &from->compress_buffer, &from->compress_buffer_size, &rsize))
+                                return -EBADMSG;
+
+                        data = from->compress_buffer;
+                        l = rsize;
+#else
+                        return -EPROTONOSUPPORT;
+#endif
+                } else
+                        data = o->data.payload;
+
+                r = journal_file_append_data(to, data, l, &u, &h);
+                if (r < 0)
+                        return r;
+
+                xor_hash ^= le64toh(u->data.hash);
+                items[i].object_offset = htole64(h);
+                items[i].hash = u->data.hash;
+
+                r = journal_file_move_to_object(from, OBJECT_ENTRY, p, &o);
+                if (r < 0)
+                        return r;
+        }
+
+        return journal_file_append_entry_internal(to, &ts, xor_hash, items, n, seqnum, ret, offset);
+}