diff options
Diffstat (limited to 'db/btree/bt_conv.c')
-rw-r--r-- | db/btree/bt_conv.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/db/btree/bt_conv.c b/db/btree/bt_conv.c new file mode 100644 index 0000000000..1cb208b14d --- /dev/null +++ b/db/btree/bt_conv.c @@ -0,0 +1,221 @@ +/*- + * Copyright (c) 1990, 1993, 1994 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Mike Olson. + * + * 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. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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. + */ + +#if defined(LIBC_SCCS) && !defined(lint) +static char sccsid[] = "@(#)bt_conv.c 8.5 (Berkeley) 8/17/94"; +#endif /* LIBC_SCCS and not lint */ + +#include <sys/param.h> + +#include <stdio.h> + +#include <db.h> +#include "btree.h" + +static void mswap __P((PAGE *)); + +/* + * __BT_BPGIN, __BT_BPGOUT -- + * Convert host-specific number layout to/from the host-independent + * format stored on disk. + * + * Parameters: + * t: tree + * pg: page number + * h: page to convert + */ +void +__bt_pgin(t, pg, pp) + void *t; + pgno_t pg; + void *pp; +{ + PAGE *h; + indx_t i, top; + u_char flags; + char *p; + + if (!F_ISSET(((BTREE *)t), B_NEEDSWAP)) + return; + if (pg == P_META) { + mswap(pp); + return; + } + + h = pp; + M_32_SWAP(h->pgno); + M_32_SWAP(h->prevpg); + M_32_SWAP(h->nextpg); + M_32_SWAP(h->flags); + M_16_SWAP(h->lower); + M_16_SWAP(h->upper); + + top = NEXTINDEX(h); + if ((h->flags & P_TYPE) == P_BINTERNAL) + for (i = 0; i < top; i++) { + M_16_SWAP(h->linp[i]); + p = (char *)GETBINTERNAL(h, i); + P_32_SWAP(p); + p += sizeof(u_int32_t); + P_32_SWAP(p); + p += sizeof(pgno_t); + if (*(u_char *)p & P_BIGKEY) { + p += sizeof(u_char); + P_32_SWAP(p); + p += sizeof(pgno_t); + P_32_SWAP(p); + } + } + else if ((h->flags & P_TYPE) == P_BLEAF) + for (i = 0; i < top; i++) { + M_16_SWAP(h->linp[i]); + p = (char *)GETBLEAF(h, i); + P_32_SWAP(p); + p += sizeof(u_int32_t); + P_32_SWAP(p); + p += sizeof(u_int32_t); + flags = *(u_char *)p; + if (flags & (P_BIGKEY | P_BIGDATA)) { + p += sizeof(u_char); + if (flags & P_BIGKEY) { + P_32_SWAP(p); + p += sizeof(pgno_t); + P_32_SWAP(p); + } + if (flags & P_BIGDATA) { + p += sizeof(u_int32_t); + P_32_SWAP(p); + p += sizeof(pgno_t); + P_32_SWAP(p); + } + } + } +} + +void +__bt_pgout(t, pg, pp) + void *t; + pgno_t pg; + void *pp; +{ + PAGE *h; + indx_t i, top; + u_char flags; + char *p; + + if (!F_ISSET(((BTREE *)t), B_NEEDSWAP)) + return; + if (pg == P_META) { + mswap(pp); + return; + } + + h = pp; + top = NEXTINDEX(h); + if ((h->flags & P_TYPE) == P_BINTERNAL) + for (i = 0; i < top; i++) { + p = (char *)GETBINTERNAL(h, i); + P_32_SWAP(p); + p += sizeof(u_int32_t); + P_32_SWAP(p); + p += sizeof(pgno_t); + if (*(u_char *)p & P_BIGKEY) { + p += sizeof(u_char); + P_32_SWAP(p); + p += sizeof(pgno_t); + P_32_SWAP(p); + } + M_16_SWAP(h->linp[i]); + } + else if ((h->flags & P_TYPE) == P_BLEAF) + for (i = 0; i < top; i++) { + p = (char *)GETBLEAF(h, i); + P_32_SWAP(p); + p += sizeof(u_int32_t); + P_32_SWAP(p); + p += sizeof(u_int32_t); + flags = *(u_char *)p; + if (flags & (P_BIGKEY | P_BIGDATA)) { + p += sizeof(u_char); + if (flags & P_BIGKEY) { + P_32_SWAP(p); + p += sizeof(pgno_t); + P_32_SWAP(p); + } + if (flags & P_BIGDATA) { + p += sizeof(u_int32_t); + P_32_SWAP(p); + p += sizeof(pgno_t); + P_32_SWAP(p); + } + } + M_16_SWAP(h->linp[i]); + } + + M_32_SWAP(h->pgno); + M_32_SWAP(h->prevpg); + M_32_SWAP(h->nextpg); + M_32_SWAP(h->flags); + M_16_SWAP(h->lower); + M_16_SWAP(h->upper); +} + +/* + * MSWAP -- Actually swap the bytes on the meta page. + * + * Parameters: + * p: page to convert + */ +static void +mswap(pg) + PAGE *pg; +{ + char *p; + + p = (char *)pg; + P_32_SWAP(p); /* magic */ + p += sizeof(u_int32_t); + P_32_SWAP(p); /* version */ + p += sizeof(u_int32_t); + P_32_SWAP(p); /* psize */ + p += sizeof(u_int32_t); + P_32_SWAP(p); /* free */ + p += sizeof(u_int32_t); + P_32_SWAP(p); /* nrecs */ + p += sizeof(u_int32_t); + P_32_SWAP(p); /* flags */ + p += sizeof(u_int32_t); +} |