src/lib-index/mail-cache-sync-update.c

	mail-cache-sync-update.c revision 2219015cc814b18a72d8d37696a5bffc52edd767
/* Copyright (c) 2004-2014 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "mail-cache-private.h"
#include "mail-index-sync-private.h"

struct mail_cache_sync_context {
    unsigned expunge_count;
};

static struct mail_cache_sync_context *mail_cache_handler_init(void **context)
{
    struct mail_cache_sync_context *ctx;

    if (*context != NULL)
        ctx = *context;
    else {
        *context = i_new(struct mail_cache_sync_context, 1);
        ctx = *context;
    }
    return ctx;
}

static void mail_cache_handler_deinit(struct mail_index_sync_map_ctx *sync_ctx,
                      struct mail_cache_sync_context *ctx)
{
    struct mail_cache *cache = sync_ctx->view->index->cache;

    if (ctx == NULL)
        return;

    if (mail_cache_lock(cache, TRUE) > 0) {
        /* update the record counts in the cache file's header. these
           are used to figure out when a cache file should be
           recreated and the old data dropped. */
        cache->hdr_copy.deleted_record_count += ctx->expunge_count;
        if (cache->hdr_copy.record_count >= ctx->expunge_count)
            cache->hdr_copy.record_count -= ctx->expunge_count;
        else
            cache->hdr_copy.record_count = 0;
        cache->hdr_modified = TRUE;
        (void)mail_cache_unlock(cache);
    }
    i_free(ctx);
}

int mail_cache_expunge_handler(struct mail_index_sync_map_ctx *sync_ctx,
                   uint32_t seq ATTR_UNUSED, const void *data,
                   void **sync_context, void *context ATTR_UNUSED)
{
    struct mail_cache_sync_context *ctx = *sync_context;
    const uint32_t *cache_offset = data;

    if (data == NULL) {
        mail_cache_handler_deinit(sync_ctx, ctx);
        *sync_context = NULL;
        return 0;
    }

    if (*cache_offset == 0)
        return 0;

    ctx = mail_cache_handler_init(sync_context);
    ctx->expunge_count++;
    return 0;
}