1 /* $OpenBSD: rec_open.c,v 1.12 2015/07/16 04:27:33 tedu Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Mike Olson. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/types.h> 36 #include <sys/mman.h> 37 #include <sys/stat.h> 38 39 #include <errno.h> 40 #include <fcntl.h> 41 #include <limits.h> 42 #include <stddef.h> 43 #include <stdio.h> 44 #include <unistd.h> 45 46 #include <db.h> 47 #include "recno.h" 48 49 DB * 50 __rec_open(const char *fname, int flags, int mode, const RECNOINFO *openinfo, 51 int dflags) 52 { 53 BTREE *t; 54 BTREEINFO btopeninfo; 55 DB *dbp; 56 PAGE *h; 57 struct stat sb; 58 int rfd, sverrno; 59 60 /* Open the user's file -- if this fails, we're done. */ 61 if (fname != NULL && (rfd = open(fname, flags, mode)) < 0) 62 return (NULL); 63 64 /* Create a btree in memory (backed by disk). */ 65 dbp = NULL; 66 if (openinfo) { 67 if (openinfo->flags & ~(R_FIXEDLEN | R_NOKEY | R_SNAPSHOT)) 68 goto einval; 69 btopeninfo.flags = 0; 70 btopeninfo.cachesize = openinfo->cachesize; 71 btopeninfo.maxkeypage = 0; 72 btopeninfo.minkeypage = 0; 73 btopeninfo.psize = openinfo->psize; 74 btopeninfo.compare = NULL; 75 btopeninfo.prefix = NULL; 76 btopeninfo.lorder = openinfo->lorder; 77 dbp = __bt_open(openinfo->bfname, 78 O_RDWR, S_IRUSR | S_IWUSR, &btopeninfo, dflags); 79 } else 80 dbp = __bt_open(NULL, O_RDWR, S_IRUSR | S_IWUSR, NULL, dflags); 81 if (dbp == NULL) 82 goto err; 83 84 /* 85 * Some fields in the tree structure are recno specific. Fill them 86 * in and make the btree structure look like a recno structure. We 87 * don't change the bt_ovflsize value, it's close enough and slightly 88 * bigger. 89 */ 90 t = dbp->internal; 91 if (openinfo) { 92 if (openinfo->flags & R_FIXEDLEN) { 93 F_SET(t, R_FIXLEN); 94 t->bt_reclen = openinfo->reclen; 95 if (t->bt_reclen == 0) 96 goto einval; 97 } 98 t->bt_bval = openinfo->bval; 99 } else 100 t->bt_bval = '\n'; 101 102 F_SET(t, R_RECNO); 103 if (fname == NULL) 104 F_SET(t, R_EOF | R_INMEM); 105 else 106 t->bt_rfd = rfd; 107 108 if (fname != NULL) { 109 /* 110 * In 4.4BSD, stat(2) returns true for ISSOCK on pipes. 111 * Unfortunately, that's not portable, so we use lseek 112 * and check the errno values. 113 */ 114 errno = 0; 115 if (lseek(rfd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) { 116 switch (flags & O_ACCMODE) { 117 case O_RDONLY: 118 F_SET(t, R_RDONLY); 119 break; 120 default: 121 goto einval; 122 } 123 slow: if ((t->bt_rfp = fdopen(rfd, "r")) == NULL) 124 goto err; 125 F_SET(t, R_CLOSEFP); 126 t->bt_irec = 127 F_ISSET(t, R_FIXLEN) ? __rec_fpipe : __rec_vpipe; 128 } else { 129 switch (flags & O_ACCMODE) { 130 case O_RDONLY: 131 F_SET(t, R_RDONLY); 132 break; 133 case O_RDWR: 134 break; 135 default: 136 goto einval; 137 } 138 139 if (fstat(rfd, &sb)) 140 goto err; 141 if (sb.st_size == 0) 142 F_SET(t, R_EOF); 143 else { 144 goto slow; 145 } 146 } 147 } 148 149 /* Use the recno routines. */ 150 dbp->close = __rec_close; 151 dbp->del = __rec_delete; 152 dbp->fd = __rec_fd; 153 dbp->get = __rec_get; 154 dbp->put = __rec_put; 155 dbp->seq = __rec_seq; 156 dbp->sync = __rec_sync; 157 158 /* If the root page was created, reset the flags. */ 159 if ((h = mpool_get(t->bt_mp, P_ROOT, 0)) == NULL) 160 goto err; 161 if ((h->flags & P_TYPE) == P_BLEAF) { 162 F_CLR(h, P_TYPE); 163 F_SET(h, P_RLEAF); 164 mpool_put(t->bt_mp, h, MPOOL_DIRTY); 165 } else 166 mpool_put(t->bt_mp, h, 0); 167 168 if (openinfo && openinfo->flags & R_SNAPSHOT && 169 !F_ISSET(t, R_EOF | R_INMEM) && 170 t->bt_irec(t, MAX_REC_NUMBER) == RET_ERROR) 171 goto err; 172 return (dbp); 173 174 einval: errno = EINVAL; 175 err: sverrno = errno; 176 if (dbp != NULL) 177 (void)__bt_close(dbp); 178 if (fname != NULL) 179 (void)close(rfd); 180 errno = sverrno; 181 return (NULL); 182 } 183 184 int 185 __rec_fd(const DB *dbp) 186 { 187 BTREE *t; 188 189 t = dbp->internal; 190 191 /* Toss any page pinned across calls. */ 192 if (t->bt_pinned != NULL) { 193 mpool_put(t->bt_mp, t->bt_pinned, 0); 194 t->bt_pinned = NULL; 195 } 196 197 /* In-memory database can't have a file descriptor. */ 198 if (F_ISSET(t, R_INMEM)) { 199 errno = ENOENT; 200 return (-1); 201 } 202 return (t->bt_rfd); 203 } 204