#ifndef LOG_INTERNAL_H
#define LOG_INTERNAL_H

#ident "Copyright (c) 2007 Tokutek Inc.  All rights reserved."

#include "brt-internal.h"
#include "log.h"
#include "toku_assert.h"
#include "list.h"
#include "memarena.h"
#include <stdio.h>
#if !defined(TOKU_WINDOWS)
#include <pthread.h>
#endif
#include <sys/types.h>
#include <string.h>

// Locking for the logger
//  For most purposes we use the big ydb lock.
// To log: grab the buf lock
//  If the buf would overflow, then grab the file lock, swap file&buf, release buf lock, write the file, write the entry, release the file lock
//  else append to buf & release lock

#define LOGGER_BUF_SIZE (1<<24)

struct mylock {
    pthread_mutex_t lock;
    int is_locked;
};

static inline int ml_init(struct mylock *l) {
    l->is_locked=0;
    return pthread_mutex_init(&l->lock, 0);
}
static inline int ml_lock(struct mylock *l) {
    int r = pthread_mutex_lock(&l->lock);
    assert(l->is_locked==0);
    l->is_locked=1;
    return r;
}
static inline int ml_unlock(struct mylock *l) {
    assert(l->is_locked==1);
    l->is_locked=0;
    return pthread_mutex_unlock(&l->lock);
}
static inline int ml_destroy(struct mylock *l) {
    assert(l->is_locked==0);
    return pthread_mutex_destroy(&l->lock);
}


struct tokulogger {
    enum typ_tag tag; // must be first
    struct mylock  input_lock, output_lock; // acquired in that order
    int is_open;
    int is_panicked;
    int write_log_files;
    int panic_errno;
    char *directory;
    int fd;
    CACHETABLE ct;
    int lg_max; // The size of the single file in the log.  Default is 100MB in TokuDB

    // To access these, you must have the input lock
    struct logbytes *head,*tail;
    LSN lsn; // the next available lsn
    struct list live_txns; // just a linked list.  Should be a hashtable.
    int n_in_buf;

    // To access these, you must have the output lock
    LSN written_lsn; // the last lsn written
    LSN fsynced_lsn; // What is the LSN of the highest fsynced log entry
    LSN checkpoint_lsns[2]; // What are the LSNs of the most recent checkpoints.  checkpoint_lsn[0] is the most recent one.
    long long next_log_file_number;
    char buf[LOGGER_BUF_SIZE]; // used to marshall logbytes so we can use only a single write
    int n_in_file;

};

int toku_logger_find_next_unused_log_file(const char *directory, long long *result);
int toku_logger_find_logfiles (const char *directory, char ***resultp);

struct brtcachefile_pair {
    BRT brt;
    CACHEFILE cf;
};

struct tokutxn {
    enum typ_tag tag;
    u_int64_t txnid64; /* this happens to be the first lsn */
    TOKULOGGER logger;
    TOKUTXN    parent;
    LSN        last_lsn; /* Everytime anything is logged, update the LSN.  (We need to atomically record the LSN along with writing into the log.) */
    LSN        first_lsn; /* The first lsn in the transaction. */
    struct roll_entry *oldest_logentry,*newest_logentry; /* Only logentries with rollbacks are here. There is a list going from newest to oldest. */
    struct list live_txns_link;

    MEMARENA   rollentry_arena;

    size_t     rollentry_resident_bytecount; // How many bytes for the rollentries that are stored in main memory.
    char      *rollentry_filename;
    int        rollentry_fd;         // If we spill the roll_entries, we write them into this fd.
    off_t      rollentry_filesize;   // How many bytes are in the rollentry.
    OMT        open_brts; // a collection of the brts that we touched.  Indexed by filenum.
};

int toku_logger_finish (TOKULOGGER logger, struct logbytes *logbytes, struct wbuf *wbuf, int do_fsync);

static inline int toku_logsizeof_u_int8_t (u_int32_t v __attribute__((__unused__))) {
    return 1;
}

static inline int toku_logsizeof_u_int32_t (u_int32_t v __attribute__((__unused__))) {
    return 4;
}

static inline int toku_logsizeof_FILENUM (FILENUM v __attribute__((__unused__))) {
    return 4;
}

static inline int toku_logsizeof_DISKOFF (DISKOFF v __attribute__((__unused__))) {
    return 8;
}
static inline int toku_logsizeof_BLOCKNUM (BLOCKNUM v __attribute__((__unused__))) {
    return 8;
}

static inline int toku_logsizeof_TXNID (TXNID txnid __attribute__((__unused__))) {
    return 8;
}

static inline int toku_logsizeof_BYTESTRING (BYTESTRING bs) {
    return 4+bs.len;
}

static inline int toku_logsizeof_LOGGEDBRTHEADER (LOGGEDBRTHEADER bs) {
    int in_both = 4+4+4+8+8+4;
    if (bs.n_named_roots==-1)
	return in_both+8;
    else {
	int sum_of_pieces=0;
	int i;
	for (i=0; i<bs.n_named_roots; i++) {
	    sum_of_pieces += 4+8+1+strlen(bs.u.many.names[i]);
	}
	return in_both+sum_of_pieces;
    }
	
}

static inline int toku_logsizeof_INTPAIRARRAY (INTPAIRARRAY pa) {
    return 4+(4+4)*pa.size;
}

static inline char *fixup_fname(BYTESTRING *f) {
    assert(f->len>0);
    char *fname = toku_malloc(f->len+1);
    memcpy(fname, f->data, f->len);
    fname[f->len]=0;
    return fname;
}

int toku_read_rollback_backwards(BREAD, struct roll_entry **item, MEMARENA);
#endif
