mariadb/newbrt/wbuf.h

#ifndef WBUF_H
#define WBUF_H
#ident "$Id$"
#ident "Copyright (c) 2007, 2008, 2009 Tokutek Inc.  All rights reserved."
#ident "The technology is licensed by the Massachusetts Institute of Technology, Rutgers State University of New Jersey, and the Research Foundation of State University of New York at Stony Brook under United States of America Serial No. 11/760379 and to the patents and/or patent applications resulting from it."

#include "x1764.h"
#include "memory.h"
#include "toku_assert.h"
#include <errno.h>
#include <string.h>

#define CRC_INCR

/* When serializing a value, write it into a buffer. */
/* This code requires that the buffer be big enough to hold whatever you put into it. */
/* This abstraction doesn't do a good job of hiding its internals.
 * Why?  The performance of this code is important, and we want to inline stuff */
//Why is size here an int instead of DISKOFF like in the initializer?
struct wbuf {
    unsigned char *buf;
    unsigned int  size;
    unsigned int  ndone;
    struct x1764  checksum;    // The checksumx state
};

static inline void wbuf_init (struct wbuf *w, void *buf, DISKOFF size) {
    w->buf=buf;
    w->size=size;
    w->ndone=0;
    x1764_init(&w->checksum);
}

/* Write a character. */
static inline void wbuf_char (struct wbuf *w, unsigned char ch) {
    assert(w->ndone<w->size);
    w->buf[w->ndone++]=ch;
    x1764_add(&w->checksum, &w->buf[w->ndone-1], 1);
}

//Write an int that MUST be in network order regardless of disk order
static void wbuf_network_int (struct wbuf *w, int32_t i) __attribute__((__unused__));
static void wbuf_network_int (struct wbuf *w, int32_t i) {
    assert(w->ndone + 4 <= w->size);
    *(u_int32_t*)(&w->buf[w->ndone]) = toku_htonl(i);
    x1764_add(&w->checksum, &w->buf[w->ndone], 4);
    w->ndone += 4;
}

static void wbuf_int (struct wbuf *w, int32_t i) {
#if 0
    wbuf_char(w, i>>24);
    wbuf_char(w, i>>16);
    wbuf_char(w, i>>8);
    wbuf_char(w, i>>0);
#else
    assert(w->ndone + 4 <= w->size);
 #if 0
    w->buf[w->ndone+0] = i>>24;
    w->buf[w->ndone+1] = i>>16;
    w->buf[w->ndone+2] = i>>8;
    w->buf[w->ndone+3] = i>>0;
 #else
    *(u_int32_t*)(&w->buf[w->ndone]) = toku_htod32(i);
 #endif
    x1764_add(&w->checksum, &w->buf[w->ndone], 4);
    w->ndone += 4;
#endif
}

static void wbuf_uint (struct wbuf *w, u_int32_t i) {
    wbuf_int(w, (int32_t)i);
}

static inline void wbuf_literal_bytes(struct wbuf *w, bytevec bytes_bv, u_int32_t nbytes) {
    const unsigned char *bytes=bytes_bv;
#if 0
    { int i; for (i=0; i<nbytes; i++) wbuf_char(w, bytes[i]); }
#else
    assert(w->ndone + nbytes <= w->size);
    memcpy(w->buf + w->ndone, bytes, (size_t)nbytes);
    x1764_add(&w->checksum, &w->buf[w->ndone], nbytes);
    w->ndone += nbytes;
#endif

}

static void wbuf_bytes (struct wbuf *w, bytevec bytes_bv, u_int32_t nbytes) {
    wbuf_uint(w, nbytes);
    wbuf_literal_bytes(w, bytes_bv, nbytes);
}

static void wbuf_ulonglong (struct wbuf *w, u_int64_t ull) {
    wbuf_uint(w, (u_int32_t)(ull>>32));
    wbuf_uint(w, (u_int32_t)(ull&0xFFFFFFFF));
}

static inline void wbuf_u_int64_t(struct wbuf *w, u_int64_t ull) {
    wbuf_ulonglong(w, ull);
}

static inline void wbuf_BYTESTRING (struct wbuf *w, BYTESTRING v) {
    wbuf_bytes(w, v.data, v.len);
}

static inline void wbuf_u_int8_t (struct wbuf *w, u_int8_t v) {
    wbuf_char(w, v);
}

static inline void wbuf_u_int32_t (struct wbuf *w, u_int32_t v) {
    wbuf_uint(w, v);
}

static inline void wbuf_DISKOFF (struct wbuf *w, DISKOFF off) {
    wbuf_ulonglong(w, (u_int64_t)off);
}
static inline void wbuf_BLOCKNUM (struct wbuf *w, BLOCKNUM b) {
    wbuf_ulonglong(w, b.b);
}



static inline void wbuf_TXNID (struct wbuf *w, TXNID tid) {
    wbuf_ulonglong(w, tid);
}

static inline void wbuf_LSN (struct wbuf *w, LSN lsn) {
    wbuf_ulonglong(w, lsn.lsn);
}

static inline void wbuf_FILENUM (struct wbuf *w, FILENUM fileid) {
    wbuf_uint(w, fileid.fileid);
}

static inline void wbuf_LOGGEDBRTHEADER (struct wbuf *w, LOGGEDBRTHEADER h) {
    wbuf_uint(w, h.size);
    wbuf_uint(w, h.flags);
    wbuf_uint(w, h.nodesize);
    wbuf_BLOCKNUM(w, h.free_blocks);
    wbuf_BLOCKNUM(w, h.unused_blocks);
    wbuf_BLOCKNUM(w, h.root);
    wbuf_BLOCKNUM(w, h.btt_size);
    wbuf_DISKOFF(w, h.btt_diskoff);
    {
	BLOCKNUM i;
	for (i.b=0; i.b<h.btt_size.b; i.b++) {
	    wbuf_DISKOFF(w, h.btt_pairs[i.b].off);
	    wbuf_int(w, h.btt_pairs[i.b].size);
	}
    }
}

static inline void wbuf_INTPAIRARRAY (struct wbuf *w, INTPAIRARRAY h) {
    u_int32_t i;
    wbuf_uint(w, h.size);
    for (i=0; i<h.size; i++) {
	wbuf_uint(w, h.array[i].a);
	wbuf_uint(w, h.array[i].b);
    }
}

#endif