cyr_backup.c

/* cyr_backup.c -- tool for examining replication-based backup files
 *
 * Copyright (c) 1994-2016 Carnegie Mellon University.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The name "Carnegie Mellon University" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For permission or any legal
 *    details, please contact
 *      Carnegie Mellon University
 *      Center for Technology Transfer and Enterprise Creation
 *      4615 Forbes Avenue
 *      Suite 302
 *      Pittsburgh, PA  15213
 *      (412) 268-7393, fax: (412) 268-7395
 *      innovation@andrew.cmu.edu
 *
 * 4. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by Computing Services
 *     at Carnegie Mellon University (http://www.cmu.edu/computing/)."
 *
 * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
 * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */

#include <config.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>

#include <assert.h>
#include <errno.h>
#include <getopt.h>
#include <jansson.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <sysexits.h>
#include <unistd.h>

#include "lib/cyrusdb.h"
#include "lib/gzuncat.h"
#include "lib/map.h"
#include "lib/strarray.h"
#include "lib/util.h"

#include "imap/global.h"
#include "imap/imap_err.h"
#include "imap/json_support.h"

#include "backup/backup.h"

static struct namespace cyr_backup_namespace;

EXPORTED void fatal(const char *error, int code)
{
    fprintf(stderr, "fatal error: %s\n", error);
    cyrus_done();
    exit(code);
}

static const char *argv0 = NULL;
static void usage(void)
{
    fprintf(stderr, "Usage:\n");
    fprintf(stderr, "    %s [options] [mode] backup list chunks\n", argv0);
    fprintf(stderr, "    %s [options] [mode] backup list mailboxes\n", argv0);
    fprintf(stderr, "    %s [options] [mode] backup list messages\n", argv0);
    fprintf(stderr, "    %s [options] [mode] backup list all\n", argv0);
    fprintf(stderr, "    %s [options] [mode] backup show chunks id...\n", argv0);
    fprintf(stderr, "    %s [options] [mode] backup show mailboxes [mboxname | uniqueid]...\n", argv0);
    fprintf(stderr, "    %s [options] [mode] backup show messages guid...\n", argv0);
    fprintf(stderr, "    %s [options] [mode] backup dump chunk id\n", argv0);
    fprintf(stderr, "    %s [options] [mode] backup dump message guid\n", argv0);
    fprintf(stderr, "    %s [options] [mode] backup json chunks\n", argv0);
    fprintf(stderr, "    %s [options] [mode] backup json mailboxes\n", argv0);
    fprintf(stderr, "    %s [options] [mode] backup json messages\n", argv0);
    fprintf(stderr, "    %s [options] [mode] backup json headers guid...\n", argv0);

    fprintf(stderr, "\n%s\n",
            "Commands:\n"
            "    list                # list specified items\n"
            "    show                # show detailed information for specified items\n"
            "    dump                # show entire item\n"
            "    json                # show detailed information in json format\n"
    );

    fprintf(stderr, "%s\n",
            "Options:\n"
            "    -C alt_config       # alternate config file\n"
            "    -v                  # verbose\n"
    );

    fprintf(stderr, "%s\n",
            "Modes:\n"
            "    -f                  # specified backup interpreted as filename\n"
            "    -m                  # specified backup interpreted as mboxname\n"
            "    -u                  # specified backup interpreted as userid (default)\n"
    );

    exit(EX_USAGE);
}

static void save_argv0(const char *s)
{
    const char *slash = strrchr(s, '/');
    if (slash)
        argv0 = slash + 1;
    else
        argv0 = s;
}

enum cyrbu_mode {
    CYRBU_MODE_UNSPECIFIED = 0,
    CYRBU_MODE_FILENAME,
    CYRBU_MODE_MBOXNAME,
    CYRBU_MODE_USERNAME,
};

struct cyrbu_cmd_options {
    strarray_t *argv;
    int verbose;
};

typedef int cyrbu_cmd_func(struct backup *,
                           const struct cyrbu_cmd_options *);

static int cmd_list_all(struct backup *backup,
                        const struct cyrbu_cmd_options *options);
static int cmd_list_chunks(struct backup *backup,
                           const struct cyrbu_cmd_options *options);
static int cmd_list_mailboxes(struct backup *backup,
                              const struct cyrbu_cmd_options *options);
static int cmd_list_messages(struct backup *backup,
                             const struct cyrbu_cmd_options *options);
static int cmd_show_chunks(struct backup *backup,
                           const struct cyrbu_cmd_options *options);
static int cmd_show_mailboxes(struct backup *backup,
                              const struct cyrbu_cmd_options *options);
static int cmd_show_messages(struct backup *backup,
                             const struct cyrbu_cmd_options *options);
static int cmd_dump_chunk(struct backup *backup,
                          const struct cyrbu_cmd_options *options);
static int cmd_dump_mailbox(struct backup *backup,
                            const struct cyrbu_cmd_options *options);
static int cmd_dump_message(struct backup *backup,
                            const struct cyrbu_cmd_options *options);
static int cmd_json_chunks(struct backup *backup,
                           const struct cyrbu_cmd_options *options);
static int cmd_json_mailboxes(struct backup *backup,
                              const struct cyrbu_cmd_options *options);
static int cmd_json_messages(struct backup *backup,
                             const struct cyrbu_cmd_options *options);
static int cmd_json_headers(struct backup *backup,
                            const struct cyrbu_cmd_options *options);

enum cyrbu_cmd {
    CYRBU_CMD_UNSPECIFIED = 0,
    CYRBU_CMD_LIST_ALL,
    CYRBU_CMD_LIST_CHUNKS,
    CYRBU_CMD_LIST_MAILBOXES,
    CYRBU_CMD_LIST_MESSAGES,
    CYRBU_CMD_SHOW_CHUNKS,
    CYRBU_CMD_SHOW_MAILBOXES,
    CYRBU_CMD_SHOW_MESSAGES,
    CYRBU_CMD_DUMP_CHUNK,
    CYRBU_CMD_DUMP_MAILBOX,
    CYRBU_CMD_DUMP_MESSAGE,
    CYRBU_CMD_JSON_CHUNKS,
    CYRBU_CMD_JSON_MAILBOXES,
    CYRBU_CMD_JSON_MESSAGES,
    CYRBU_CMD_JSON_HEADERS,
};

static cyrbu_cmd_func *const cmd_func[] = {
    NULL,
    cmd_list_all,
    cmd_list_chunks,
    cmd_list_mailboxes,
    cmd_list_messages,
    cmd_show_chunks,
    cmd_show_mailboxes,
    cmd_show_messages,
    cmd_dump_chunk,
    cmd_dump_mailbox,
    cmd_dump_message,
    cmd_json_chunks,
    cmd_json_mailboxes,
    cmd_json_messages,
    cmd_json_headers,
};

static enum cyrbu_cmd parse_cmd_string(const char *command, const char *sub)
{
    switch (command[0]) {
    case 'd':
        if (strcmp(command, "dump") == 0) {
            if (strcmp(sub, "chunk") == 0) return CYRBU_CMD_DUMP_CHUNK;
            else if (strcmp(sub, "mailbox") == 0) return CYRBU_CMD_DUMP_MAILBOX;
            else if (strcmp(sub, "message") == 0) return CYRBU_CMD_DUMP_MESSAGE;
        }
        break;
    case 'j':
        if (strcmp(command, "json") == 0) {
            if (strcmp(sub, "chunks") == 0) return CYRBU_CMD_JSON_CHUNKS;
            else if (strcmp(sub, "mailboxes") == 0) return CYRBU_CMD_JSON_MAILBOXES;
            else if (strcmp(sub, "messages") == 0) return CYRBU_CMD_JSON_MESSAGES;
            else if (strcmp(sub, "headers") == 0) return CYRBU_CMD_JSON_HEADERS;
        }
        break;
    case 'l':
        if (strcmp(command, "list") == 0) {
            if (strcmp(sub, "all") == 0) return CYRBU_CMD_LIST_ALL;
            else if (strcmp(sub, "chunks") == 0) return CYRBU_CMD_LIST_CHUNKS;
            else if (strcmp(sub, "mailboxes") == 0) return CYRBU_CMD_LIST_MAILBOXES;
            else if (strcmp(sub, "messages") == 0) return CYRBU_CMD_LIST_MESSAGES;
        }
        break;
    case 's':
        if (strcmp(command, "show") == 0) {
            if (strcmp(sub, "chunks") == 0) return CYRBU_CMD_SHOW_CHUNKS;
            else if (strcmp(sub, "mailboxes") == 0) return CYRBU_CMD_SHOW_MAILBOXES;
            else if (strcmp(sub, "messages") == 0) return CYRBU_CMD_SHOW_MESSAGES;
        }
        break;
    default:
        break;
    }

    return CYRBU_CMD_UNSPECIFIED;
}

int main(int argc, char **argv)
{
    save_argv0(argv[0]);

    struct cyrbu_cmd_options options = {0};
    enum cyrbu_mode mode = CYRBU_MODE_UNSPECIFIED;
    enum cyrbu_cmd cmd = CYRBU_CMD_UNSPECIFIED;
    const char *alt_config = NULL;
    const char *backup_name = NULL;
    const char *command = NULL;
    const char *subcommand = NULL;
    struct backup *backup = NULL;
    mbname_t *mbname = NULL;
    int i, opt, r = 0;

    /* keep this in alphabetical order */
    static const char short_options[] = "C:fmuv";

    static const struct option long_options[] = {
        /* n.b. no long option for -C */
        { "filename", no_argument, NULL, 'f' },
        { "mailbox", no_argument, NULL, 'm' },
        { "userid", no_argument, NULL, 'u' },
        { "verbose", no_argument, NULL, 'v' },

        { 0, 0, 0, 0 },
    };

    while (-1 != (opt = getopt_long(argc, argv,
                                    short_options, long_options, NULL)))
    {
        switch (opt) {
        case 'C':
            alt_config = optarg;
            break;
        case 'f':
            if (mode != CYRBU_MODE_UNSPECIFIED) usage();
            mode = CYRBU_MODE_FILENAME;
            break;
        case 'm':
            if (mode != CYRBU_MODE_UNSPECIFIED) usage();
            mode = CYRBU_MODE_MBOXNAME;
            break;
        case 'u':
            if (mode != CYRBU_MODE_UNSPECIFIED) usage();
            mode = CYRBU_MODE_USERNAME;
            break;
        case 'v':
            options.verbose++;
            break;
        default:
            usage();
            break;
        }
    }

    /* default mode is username */
    if (mode == CYRBU_MODE_UNSPECIFIED)
        mode = CYRBU_MODE_USERNAME;

    /* get the backup name */
    if (optind == argc) usage();
    backup_name = argv[optind++];

    /* get the command */
    if (optind == argc) usage();
    command = argv[optind++];

    /* get the subcommand */
    if (optind == argc) usage();
    subcommand = argv[optind++];

    /* parse the command and subcommand */
    cmd = parse_cmd_string(command, subcommand);

    /* check remaining arguments based on command */
    switch (cmd) {
    case CYRBU_CMD_LIST_ALL:
    case CYRBU_CMD_LIST_CHUNKS:
    case CYRBU_CMD_LIST_MAILBOXES:
    case CYRBU_CMD_LIST_MESSAGES:
    case CYRBU_CMD_JSON_CHUNKS:
    case CYRBU_CMD_JSON_MAILBOXES:
    case CYRBU_CMD_JSON_MESSAGES:
        /* these want no more arguments */
        if (optind != argc) usage();
        break;
    case CYRBU_CMD_SHOW_CHUNKS:
    case CYRBU_CMD_SHOW_MAILBOXES:
    case CYRBU_CMD_SHOW_MESSAGES:
    case CYRBU_CMD_JSON_HEADERS:
        /* these need at least one more argument */
        if (optind == argc) usage();
        break;
    case CYRBU_CMD_DUMP_CHUNK:
    case CYRBU_CMD_DUMP_MAILBOX:
    case CYRBU_CMD_DUMP_MESSAGE:
        /* these need exactly one more argument */
        if (argc - optind != 1) usage();
        break;
    default:
        usage();
        break;
    }

    /* build a nice args list */
    options.argv = strarray_new();
    for (i = optind; i < argc; i++) {
        strarray_add(options.argv, argv[i]);
    }

    // FIXME finish parsing options

    cyrus_init(alt_config, "cyr_backup", 0, 0);

    if ((r = mboxname_init_namespace(&cyr_backup_namespace, NAMESPACE_OPTION_ADMIN))) {
        fatal(error_message(r), EX_CONFIG);
    }
    mboxevent_setnamespace(&cyr_backup_namespace);

    /* use xmalloc rather than malloc for json internals */
    json_set_alloc_funcs(xmalloc, free);

    /* open backup */
    switch (mode) {
    case CYRBU_MODE_FILENAME:
        r = backup_open_paths(&backup, backup_name, NULL,
                              BACKUP_OPEN_BLOCK, BACKUP_OPEN_NOCREATE);
        break;
    case CYRBU_MODE_MBOXNAME:
        mbname = mbname_from_extname(backup_name, &cyr_backup_namespace, NULL);
        if (!mbname) usage();
        r = backup_open(&backup, mbname,
                        BACKUP_OPEN_BLOCK, BACKUP_OPEN_NOCREATE);
        break;
    case CYRBU_MODE_USERNAME:
        mbname = mbname_from_userid(backup_name);
        if (!mbname) usage();
        r = backup_open(&backup, mbname,
                        BACKUP_OPEN_BLOCK, BACKUP_OPEN_NOCREATE);
        break;
    default:
        usage();
        break;
    }

    /* verify the backup */
    if (!r)
        r = backup_verify(backup, BACKUP_VERIFY_QUICK, options.verbose, stdout);

    /* run command */
    if (!r && cmd_func[cmd])
        r = cmd_func[cmd](backup, &options);

    if (r) {
        fprintf(stderr, "%s: %s\n", backup_name, error_message(r));
        syslog(LOG_ERR, "backup error %s: %s",  backup_name, error_message(r));
    }

    /* close backup */
    if (backup)
        backup_close(&backup);

    /* clean up and exit */
    mbname_free(&mbname);
    backup_cleanup_staging_path();
    cyrus_done();

    strarray_free(options.argv);
    exit(r ? EX_TEMPFAIL : EX_OK);
}

static int cmd_list_all(struct backup *backup,
                        const struct cyrbu_cmd_options *options)
{
    fprintf(stderr, "listing chunks:\n");
    cmd_list_chunks(backup, options);

    fprintf(stderr, "\nlisting mailboxes:\n");
    cmd_list_mailboxes(backup, options);

    fprintf(stderr, "\nlisting messages:\n");
    cmd_list_messages(backup, options);

    return 0;
}

static int cmd_list_chunks(struct backup *backup,
                           const struct cyrbu_cmd_options *options)
{
    struct backup_chunk_list *chunk_list = NULL;
    struct backup_chunk *chunk;
    struct stat data_stat_buf;
    int r;

    (void) options;

    r = backup_stat(backup, &data_stat_buf, NULL);
    if (r) return r;

    chunk_list = backup_get_chunks(backup);
    if (!chunk_list) return -1;

    fprintf(stdout, "     id offset\tlength\tratio%%\tstart time           end time\n");
    for (chunk = chunk_list->head; chunk; chunk = chunk->next) {
        char ts_start[32] = "[unknown]";
        char ts_end[32] = "[unknown]";
        double ratio;

        strftime(ts_start, sizeof(ts_start), "%F %T",
                 localtime(&chunk->ts_start));
        strftime(ts_end, sizeof(ts_end), "%F %T",
                 localtime(&chunk->ts_end));

        if (chunk->next) {
            ratio = 100.0 * (chunk->next->offset - chunk->offset) / chunk->length;
        }
        else {
            ratio = 100.0 * (data_stat_buf.st_size - chunk->offset) / chunk->length;
        }

        fprintf(stdout, "%7d " OFF_T_FMT "\t" SIZE_T_FMT "\t%6.1f\t%s  %s\n",
                        chunk->id,
                        chunk->offset,
                        chunk->length,
                        ratio,
                        ts_start,
                        ts_end);
    }

    backup_chunk_list_free(&chunk_list);
    return 0;
}

static int list_mailbox_cb(const struct backup_mailbox *mailbox,
                           void *rock)
{
    const struct cyrbu_cmd_options *options =
        (const struct cyrbu_cmd_options *) rock;
    char ts_last_appenddate[32] = "[unknown]";

    (void) options;

    strftime(ts_last_appenddate, sizeof(ts_last_appenddate), "%F %T",
             localtime(&mailbox->last_appenddate));

    fprintf(stdout, "%s  %s  %s\n",
                    mailbox->uniqueid,
                    ts_last_appenddate,
                    mailbox->mboxname);

    return 0;
}

static int cmd_list_mailboxes(struct backup *backup,
                              const struct cyrbu_cmd_options *options)
{
    fprintf(stdout, "%-36s  %-19s  %s\n",
                    "uniqueid",
                    "last append date",
                    "mboxname");

    return backup_mailbox_foreach(backup, 0,
                                  BACKUP_MAILBOX_NO_RECORDS,
                                  list_mailbox_cb, (void *) options);
}

static int list_message_cb(const struct backup_message *message, void *rock)
{
    const struct cyrbu_cmd_options *options =
        (const struct cyrbu_cmd_options *) rock;

    (void) options;

    fprintf(stdout, "%s\n", message_guid_encode(message->guid));

    return 0;
}

static int cmd_list_messages(struct backup *backup,
                             const struct cyrbu_cmd_options *options)
{
    return backup_message_foreach(backup, 0, NULL,
                                  list_message_cb, (void *) options);
}

static int cmd_show_chunks(struct backup *backup,
                           const struct cyrbu_cmd_options *options)
{
    // FIXME
    (void) backup;
    (void) options;
    fprintf(stderr, "%s: unimplemented\n", __func__);
    return -1;
}

static int cmd_show_mailboxes(struct backup *backup,
                              const struct cyrbu_cmd_options *options)
{
    struct backup_mailbox *mailbox = NULL;
    struct backup_mailbox_message *record = NULL;
    int i;

    for (i = 0; i < strarray_size(options->argv); i++) {
        char ts_deleted[32] = "";
        const char *arg = strarray_nth(options->argv, i);

        /* argument could be a uniqueid */
        mailbox = backup_get_mailbox_by_uniqueid(backup, arg,
                                                 BACKUP_MAILBOX_ALL_RECORDS);

        /* or it could be an mboxname */
        if (!mailbox) {
            mbname_t *mbname = mbname_from_extname(arg,
                                                   &cyr_backup_namespace,
                                                   NULL);
            if (!mbname) continue;
            mailbox = backup_get_mailbox_by_name(backup, mbname,
                                                 BACKUP_MAILBOX_ALL_RECORDS);
            mbname_free(&mbname);
        }

        /* or it could be junk */
        if (!mailbox) continue;

        fprintf(stdout, "mboxname: %s\n", mailbox->mboxname);
        fprintf(stdout, "uniqueid: %s\n", mailbox->uniqueid);

        if (mailbox->deleted) {
            strftime(ts_deleted, sizeof(ts_deleted), "%F %T",
                     localtime(&mailbox->deleted));

            fprintf(stdout, "deleted:  %s\n", ts_deleted);
        }

        fprintf(stdout, "messages:\n");
        fprintf(stdout, "       uid  expunged time        guid\n");

        for (record = mailbox->records->head; record; record = record->next) {
            char ts_expunged[32] = "                   ";

            if (record->expunged)
                strftime(ts_expunged, sizeof(ts_expunged), "%F %T",
                         localtime(&record->expunged));

            fprintf(stdout, "%10d  %s  %s\n",
                            record->uid,
                            ts_expunged,
                            message_guid_encode(&record->guid));
        }

        fprintf(stdout, "\n");

        backup_mailbox_free(&mailbox);
    }

    return 0;
}

static int show_message_headers(const struct buf *buf, void *rock)
{
    FILE *out = (FILE *) rock;

    const char *start = buf_cstring(buf);
    const char *end = strstr(start, "\r\n\r\n");

    if (!end) return -1;

    fwrite(start, 1, end - start, out);
    fputs("\r\n", out);

    return 0;
}

static int cmd_show_messages(struct backup *backup,
                             const struct cyrbu_cmd_options *options)
{
    struct backup_message *message = NULL;
    struct backup_mailbox_list *mailboxes = NULL;
    struct backup_mailbox *mailbox;
    struct message_guid want_guid;
    int i;

    for (i = 0; i < strarray_size(options->argv); i++) {
        if (!message_guid_decode(&want_guid, strarray_nth(options->argv, i)))
            continue;

        message = backup_get_message(backup, &want_guid);
        if (!message)
            continue;

        fprintf(stdout, "guid:\t%s\n", message_guid_encode(message->guid));

        mailboxes = backup_get_mailboxes_by_message(backup, message,
                                                    BACKUP_MAILBOX_NO_RECORDS);
        if (mailboxes) {
            fprintf(stdout, "mailboxes:\n");
            for (mailbox = mailboxes->head; mailbox; mailbox = mailbox->next) {
                fprintf(stdout, "\t%s\t%s\n",
                                mailbox->uniqueid,
                                mailbox->mboxname);
            }

            backup_mailbox_list_empty(mailboxes);
            free(mailboxes);
        }

        fprintf(stdout, "headers:\n");
        backup_read_message_data(backup, message,
                                 show_message_headers, stdout);

        fprintf(stdout, "\n");
        backup_message_free(&message);
    }

    return 0;
}

static int dump_buf(const struct buf *buf, void *rock)
{
    FILE *out = (FILE *) rock;
    int r = fputs(buf_cstring(buf), out);
    return r < 0 ? r : 0;
}

static int cmd_dump_chunk(struct backup *backup,
                          const struct cyrbu_cmd_options *options)
{
    struct backup_chunk *chunk = NULL;
    int chunk_id;
    int r;

    chunk_id = atoi(strarray_nth(options->argv, 0));
    if (chunk_id <= 0) return -1;

    chunk = backup_get_chunk(backup, chunk_id);
    if (!chunk) return IMAP_NOTFOUND;

    r = backup_read_chunk_data(backup, chunk, dump_buf, stdout);

    backup_chunk_free(&chunk);
    return r;
}

static int cmd_dump_mailbox(struct backup *backup,
                            const struct cyrbu_cmd_options *options)
{
    // FIXME
    (void) backup;
    (void) options;
    fprintf(stderr, "%s: unimplemented\n", __func__);
    return -1;
}

static int cmd_dump_message(struct backup *backup,
                            const struct cyrbu_cmd_options *options)
{
    struct backup_message *message = NULL;
    struct message_guid want_guid;
    int r;

    if (!message_guid_decode(&want_guid, strarray_nth(options->argv, 0)))
        return IMAP_NOTFOUND;

    message = backup_get_message(backup, &want_guid);
    if (!message)
        return IMAP_NOTFOUND;

    r = backup_read_message_data(backup, message, dump_buf, stdout);

    backup_message_free(&message);

    return r;
}

static int cmd_json_chunks(struct backup *backup,
                           const struct cyrbu_cmd_options *options)
{
    struct backup_chunk_list *chunks = NULL;
    struct backup_chunk *chunk = NULL;
    json_t *jchunks = NULL;
    struct stat data_stat_buf;
    int r;

    (void) options;

    r = backup_stat(backup, &data_stat_buf, NULL);
    if (r) return r;

    jchunks = json_array();
    chunks = backup_get_chunks(backup);

    for (chunk = chunks->head; chunk; chunk = chunk->next) {
        char ts_start[32] = "[unknown]";
        char ts_end[32] = "[unknown]";
        json_t *jchunk = json_object();
        double ratio;

        strftime(ts_start, sizeof(ts_start), "%F %T",
                localtime(&chunk->ts_start));
        strftime(ts_end, sizeof(ts_end), "%F %T",
                localtime(&chunk->ts_end));

        if (chunk->next) {
            ratio = 100.0 * (chunk->next->offset - chunk->offset) / chunk->length;
        }
        else {
            ratio = 100.0 * (data_stat_buf.st_size - chunk->offset) / chunk->length;
        }

        /* XXX which fields do we want? */
        json_object_set_new(jchunk, "id", json_integer(chunk->id));
        json_object_set_new(jchunk, "offset", json_integer(chunk->offset));
        json_object_set_new(jchunk, "length", json_integer(chunk->length));
        json_object_set_new(jchunk, "ratio", json_real(ratio));
        json_object_set_new(jchunk, "start time", json_string(ts_start));
        json_object_set_new(jchunk, "end time", json_string(ts_end));

        json_array_append_new(jchunks, jchunk);
    }

    backup_chunk_list_free(&chunks);

    if (!r) {
        const int flags = JSON_PRESERVE_ORDER | JSON_INDENT(2);
        char *dump;

        dump = json_dumps(jchunks, flags);
        printf("%s\n", dump);
        free(dump);
    }

    json_decref(jchunks);
    return r;
}

static int json_mailbox_cb(const struct backup_mailbox *mailbox, void *rock)
{
    json_t *jmailboxes = (json_t *) rock;
    json_t *jmailbox = json_object();
    char ts_last_appenddate[32] = "[unknown]";

    strftime(ts_last_appenddate, sizeof(ts_last_appenddate), "%F %T",
             localtime(&mailbox->last_appenddate));

    /* XXX which fields are we interested in? */
    json_object_set_new(jmailbox, "uniqueid", json_string(mailbox->uniqueid));
    json_object_set_new(jmailbox, "mboxname", json_string(mailbox->mboxname));
    json_object_set_new(jmailbox, "last_appenddate", json_string(ts_last_appenddate));

    if (mailbox->records && mailbox->records->count) {
        struct backup_mailbox_message *iter;
        json_t *jmessages = json_array();

        for (iter = mailbox->records->head; iter; iter = iter->next) {
            json_t *jrecord = json_object();

            json_object_set_new(jrecord, "uid", json_integer(iter->uid));
            json_object_set_new(jrecord, "guid",
                                json_string(message_guid_encode(&iter->guid)));

            if (iter->expunged) {
                char ts_expunged[32] = "                   ";
                strftime(ts_expunged, sizeof(ts_expunged), "%F %T",
                         localtime(&iter->expunged));
                json_object_set_new(jrecord, "expunged",
                                    json_string(ts_expunged));
            }

            json_array_append_new(jmessages, jrecord);
        }

        json_object_set_new(jmailbox, "messages", jmessages);
    }

    json_array_append_new(jmailboxes, jmailbox);
    return 0;
}

static int cmd_json_mailboxes(struct backup *backup,
                              const struct cyrbu_cmd_options *options)
{
    json_t *mailboxes = json_array();
    int r;

    (void) options;

    r = backup_mailbox_foreach(backup, 0, BACKUP_MAILBOX_ALL_RECORDS,
                               json_mailbox_cb, mailboxes);

    if (!r) {
        const int flags = JSON_PRESERVE_ORDER | JSON_INDENT(2);
        char *dump;

        dump = json_dumps(mailboxes, flags);
        printf("%s\n", dump);
        free(dump);
    }

    json_decref(mailboxes);
    return r;
}

struct json_message_rock {
    struct backup *backup;
    json_t *jmessages;
};

static int json_message_cb(const struct backup_message *message, void *rock)
{
    struct json_message_rock *jmrock = (struct json_message_rock *) rock;
    struct backup_mailbox_list *mailboxes;
    struct backup_mailbox *mailbox;
    json_t *jmessage = json_object();

    /* XXX what fields do we want? */
    json_object_set_new(jmessage, "guid",
                        json_string(message_guid_encode(message->guid)));

    mailboxes = backup_get_mailboxes_by_message(jmrock->backup, message,
                                                BACKUP_MAILBOX_NO_RECORDS);
    if (mailboxes && mailboxes->count) {
        json_t *jmailboxes = json_array();

        for (mailbox = mailboxes->head; mailbox; mailbox = mailbox->next) {
            json_t *jmailbox = json_object();

            json_object_set_new(jmailbox, "uniqueid",
                                json_string(mailbox->uniqueid));
            json_object_set_new(jmailbox, "mboxname",
                                json_string(mailbox->mboxname));

            json_array_append_new(jmailboxes, jmailbox);
        }

        json_object_set_new(jmessage, "mailboxes", jmailboxes);
    }
    backup_mailbox_list_empty(mailboxes);
    free(mailboxes);

    json_array_append_new(jmrock->jmessages, jmessage);

    return 0;
}

static int cmd_json_messages(struct backup *backup,
                             const struct cyrbu_cmd_options *options)
{
    json_t *messages = json_array();
    struct json_message_rock rock = { backup, messages };
    int r;

    (void) options;

    r = backup_message_foreach(backup, 0, NULL, json_message_cb, &rock);

    if (!r) {
        const int flags = JSON_PRESERVE_ORDER | JSON_INDENT(2);
        char *dump;

        dump = json_dumps(messages, flags);
        printf("%s\n", dump);
        free(dump);
    }

    json_decref(messages);
    return r;
}

static int json_headers_cb(const struct buf *buf, void *rock)
{
    const char *header = NULL, *next = buf_cstring(buf);
    char *name = NULL;
    char *value = NULL;
    size_t len;
    json_t *jmessage = (json_t *) rock;
    json_t *jheader;

    while (next && *next) {
        header = next;

        /* advance next pointer before we carry on */
        do {
            next = strchr(next + 1, '\n');
        } while (next && (next[1] == ' ' || next[1] == '\t'));
        if (next) {
            if (next[1] == '\0'         /* end of file */
                || next[1] == '\n'      /* two line breaks in a row marks end of headers */
                || (next[1] == '\r' && next[2] == '\n')) {
                next = NULL;
            }
            else {
                next++;
            }
        }

        /* now process the current header */
        len = strcspn(header, ":\r\n");
        if (header[len] != ':')
            continue;

        name = xstrndup(header, len);
        message_parse_string(header + len + 1, &value);

        jheader = json_object_get(jmessage, name);
        if (!jheader) {
            jheader = json_array();
            json_object_set_new(jmessage, name, jheader);
        }

        json_array_append_new(jheader, json_string(value));

        free(name);
        free(value);
        name = value = NULL;
    }

    return 0;
}

static int cmd_json_headers(struct backup *backup,
                            const struct cyrbu_cmd_options *options)
{
    json_t *jmessages = json_object();
    json_t *jheaders = NULL;
    struct backup_message *message = NULL;
    struct message_guid want_guid;
    int i, r = 0;

    for (i = 0; i < strarray_size(options->argv); i++) {
        if (!message_guid_decode(&want_guid, strarray_nth(options->argv, i)))
            continue;

        message = backup_get_message(backup, &want_guid);
        if (!message)
            continue;

        jheaders = json_object();
        backup_read_message_data(backup, message, json_headers_cb, jheaders);

        json_object_set_new(jmessages, message_guid_encode(&want_guid), jheaders);
        jheaders = NULL;

        backup_message_free(&message);
    }

    if (!r) {
        const int flags = JSON_PRESERVE_ORDER | JSON_INDENT(2);
        char *dump;

        dump = json_dumps(jmessages, flags);
        printf("%s\n", dump);
        free(dump);
    }

    json_decref(jmessages);
    return r;
}