jlog.h

/*
 * Copyright (c) 2005-2008, Message Systems, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *    * Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *    * 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.
 *    * Neither the name Message Systems, Inc. nor the names
 *      of its contributors may be used to endorse or promote products
 *      derived from this software without specific prior written
 *      permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef _JLOG_H
#define _JLOG_H

#include "jlog_config.h"

#ifndef JLOG_API
# ifdef _WIN32
#  ifdef JLOG_EXPORTS
#   define JLOG_API(x) __declspec(dllexport) x
#  else
#   define JLOG_API(x) __declspec(dllimport) x
#  endif
# else
#  ifdef __cplusplus
#    define JLOG_API(x)  extern "C" x
#  else
#    define JLOG_API(x)  x
#  endif
# endif
#endif

struct _jlog_ctx;
struct _jlog_message_header;
struct _jlog_id;

typedef struct _jlog_ctx jlog_ctx;

typedef struct _jlog_message_header {
  u_int32_t reserved;
  u_int32_t tv_sec;
  u_int32_t tv_usec;
  u_int32_t mlen;
} jlog_message_header;

typedef struct _jlog_id {
  u_int32_t log;
  u_int32_t marker;
} jlog_id;

#define JLOG_ID_ADVANCE(id) (id)->marker++

typedef struct _jlog_message {
  jlog_message_header *header;
  u_int32_t mess_len;
  void *mess;
  jlog_message_header aligned_header;
} jlog_message;

typedef enum {
  JLOG_BEGIN,
  JLOG_END
} jlog_position;

typedef enum {
  JLOG_UNSAFE,
  JLOG_ALMOST_SAFE,
  JLOG_SAFE
} jlog_safety;

typedef enum {
  JLOG_ERR_SUCCESS = 0,
  JLOG_ERR_ILLEGAL_INIT,
  JLOG_ERR_ILLEGAL_OPEN,
  JLOG_ERR_OPEN,
  JLOG_ERR_NOTDIR,
  JLOG_ERR_CREATE_PATHLEN,
  JLOG_ERR_CREATE_EXISTS,
  JLOG_ERR_CREATE_MKDIR,
  JLOG_ERR_CREATE_META,
  JLOG_ERR_LOCK,
  JLOG_ERR_IDX_OPEN,
  JLOG_ERR_IDX_SEEK,
  JLOG_ERR_IDX_CORRUPT,
  JLOG_ERR_IDX_WRITE,
  JLOG_ERR_IDX_READ,
  JLOG_ERR_FILE_OPEN,
  JLOG_ERR_FILE_SEEK,
  JLOG_ERR_FILE_CORRUPT,
  JLOG_ERR_FILE_READ,
  JLOG_ERR_FILE_WRITE,
  JLOG_ERR_META_OPEN,
  JLOG_ERR_ILLEGAL_WRITE,
  JLOG_ERR_ILLEGAL_CHECKPOINT,
  JLOG_ERR_INVALID_SUBSCRIBER,
  JLOG_ERR_ILLEGAL_LOGID,
  JLOG_ERR_SUBSCRIBER_EXISTS,
  JLOG_ERR_CHECKPOINT,
  JLOG_ERR_NOT_SUPPORTED,
} jlog_err;

typedef void (*jlog_error_func) (void *ctx, const char *msg, ...);

JLOG_API(jlog_ctx *) jlog_new(const char *path);
JLOG_API(void)      jlog_set_error_func(jlog_ctx *ctx, jlog_error_func Func, void *ptr); 
JLOG_API(size_t)    jlog_raw_size(jlog_ctx *ctx);
JLOG_API(int)       jlog_ctx_init(jlog_ctx *ctx);
JLOG_API(int)       jlog_get_checkpoint(jlog_ctx *ctx, const char *s, jlog_id *id);
JLOG_API(int)       jlog_ctx_list_subscribers_dispose(jlog_ctx *ctx, char **subs);
JLOG_API(int)       jlog_ctx_list_subscribers(jlog_ctx *ctx, char ***subs);

JLOG_API(int)       jlog_ctx_err(jlog_ctx *ctx);
JLOG_API(const char *) jlog_ctx_err_string(jlog_ctx *ctx);
JLOG_API(int)       jlog_ctx_errno(jlog_ctx *ctx);
JLOG_API(int)       jlog_ctx_open_writer(jlog_ctx *ctx);
JLOG_API(int)       jlog_ctx_open_reader(jlog_ctx *ctx, const char *subscriber);
JLOG_API(int)       jlog_ctx_close(jlog_ctx *ctx);

JLOG_API(int)       jlog_ctx_alter_mode(jlog_ctx *ctx, int mode);
JLOG_API(int)       jlog_ctx_alter_journal_size(jlog_ctx *ctx, size_t size);
JLOG_API(int)       jlog_ctx_alter_safety(jlog_ctx *ctx, jlog_safety safety);
JLOG_API(int)       jlog_ctx_add_subscriber(jlog_ctx *ctx, const char *subscriber,
                                            jlog_position whence);
JLOG_API(int)       jlog_ctx_remove_subscriber(jlog_ctx *ctx, const char *subscriber);

JLOG_API(int)       jlog_ctx_write(jlog_ctx *ctx, const void *message, size_t mess_len);
JLOG_API(int)       jlog_ctx_write_message(jlog_ctx *ctx, jlog_message *msg, struct timeval *when);
JLOG_API(int)       jlog_ctx_read_interval(jlog_ctx *ctx,
                                           jlog_id *first_mess, jlog_id *last_mess);
JLOG_API(int)       jlog_ctx_read_message(jlog_ctx *ctx, const jlog_id *, jlog_message *);
JLOG_API(int)       jlog_ctx_read_checkpoint(jlog_ctx *ctx, const jlog_id *checkpoint);
JLOG_API(int)       jlog_snprint_logid(char *buff, int n, const jlog_id *checkpoint);

JLOG_API(int)       __jlog_pending_readers(jlog_ctx *ctx, u_int32_t log);
JLOG_API(int)       jlog_ctx_first_log_id(jlog_ctx *ctx, jlog_id *id);
JLOG_API(int)       jlog_ctx_last_log_id(jlog_ctx *ctx, jlog_id *id);
JLOG_API(int)       jlog_ctx_advance_id(jlog_ctx *ctx, jlog_id *cur, 
                                        jlog_id *start, jlog_id *finish);


#endif