1 /*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #if defined(LIBC_SCCS) && !defined(lint) 35 /* from: static char sccsid[] = "@(#)rec_get.c 8.2 (Berkeley) 9/7/93"; */ 36 static char *rcsid = "$Id: rec_get.c,v 1.5 1994/02/24 09:03:39 cgd Exp $"; 37 #endif /* LIBC_SCCS and not lint */ 38 39 #include <sys/types.h> 40 41 #include <errno.h> 42 #include <stddef.h> 43 #include <stdio.h> 44 #include <stdlib.h> 45 #include <string.h> 46 #include <unistd.h> 47 48 #include <db.h> 49 #include "recno.h" 50 51 /* 52 * __REC_GET -- Get a record from the btree. 53 * 54 * Parameters: 55 * dbp: pointer to access method 56 * key: key to find 57 * data: data to return 58 * flag: currently unused 59 * 60 * Returns: 61 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found. 62 */ 63 int 64 __rec_get(dbp, key, data, flags) 65 const DB *dbp; 66 const DBT *key; 67 DBT *data; 68 u_int flags; 69 { 70 BTREE *t; 71 EPG *e; 72 recno_t nrec; 73 int status; 74 75 t = dbp->internal; 76 77 /* Toss any page pinned across calls. */ 78 if (t->bt_pinned != NULL) { 79 mpool_put(t->bt_mp, t->bt_pinned, 0); 80 t->bt_pinned = NULL; 81 } 82 83 /* Get currently doesn't take any flags, and keys of 0 are illegal. */ 84 if (flags || (nrec = *(recno_t *)key->data) == 0) { 85 errno = EINVAL; 86 return (RET_ERROR); 87 } 88 89 /* 90 * If we haven't seen this record yet, try to find it in the 91 * original file. 92 */ 93 if (nrec > t->bt_nrecs) { 94 if (ISSET(t, R_EOF | R_INMEM)) 95 return (RET_SPECIAL); 96 if ((status = t->bt_irec(t, nrec)) != RET_SUCCESS) 97 return (status); 98 } 99 100 --nrec; 101 if ((e = __rec_search(t, nrec, SEARCH)) == NULL) 102 return (RET_ERROR); 103 104 status = __rec_ret(t, e, 0, NULL, data); 105 if (ISSET(t, B_DB_LOCK)) 106 mpool_put(t->bt_mp, e->page, 0); 107 else 108 t->bt_pinned = e->page; 109 return (status); 110 } 111 112 /* 113 * __REC_FPIPE -- Get fixed length records from a pipe. 114 * 115 * Parameters: 116 * t: tree 117 * cnt: records to read 118 * 119 * Returns: 120 * RET_ERROR, RET_SUCCESS 121 */ 122 int 123 __rec_fpipe(t, top) 124 BTREE *t; 125 recno_t top; 126 { 127 DBT data; 128 recno_t nrec; 129 size_t len; 130 int ch; 131 char *p; 132 133 if (t->bt_dbufsz < t->bt_reclen) { 134 if ((t->bt_dbuf = realloc(t->bt_dbuf, t->bt_reclen)) == NULL) 135 return (RET_ERROR); 136 t->bt_dbufsz = t->bt_reclen; 137 } 138 data.data = t->bt_dbuf; 139 data.size = t->bt_reclen; 140 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 141 len = t->bt_reclen; 142 for (p = t->bt_dbuf;; *p++ = ch) 143 if ((ch = getc(t->bt_rfp)) == EOF || !len--) { 144 if (__rec_iput(t, nrec, &data, 0) 145 != RET_SUCCESS) 146 return (RET_ERROR); 147 break; 148 } 149 if (ch == EOF) 150 break; 151 } 152 if (nrec < top) { 153 SET(t, R_EOF); 154 return (RET_SPECIAL); 155 } 156 return (RET_SUCCESS); 157 } 158 159 /* 160 * __REC_VPIPE -- Get variable length records from a pipe. 161 * 162 * Parameters: 163 * t: tree 164 * cnt: records to read 165 * 166 * Returns: 167 * RET_ERROR, RET_SUCCESS 168 */ 169 int 170 __rec_vpipe(t, top) 171 BTREE *t; 172 recno_t top; 173 { 174 DBT data; 175 recno_t nrec; 176 indx_t len; 177 size_t sz; 178 int bval, ch; 179 char *p; 180 181 bval = t->bt_bval; 182 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 183 for (p = t->bt_dbuf, sz = t->bt_dbufsz;; *p++ = ch, --sz) { 184 if ((ch = getc(t->bt_rfp)) == EOF || ch == bval) { 185 data.data = t->bt_dbuf; 186 data.size = p - t->bt_dbuf; 187 if (ch == EOF && data.size == 0) 188 break; 189 if (__rec_iput(t, nrec, &data, 0) 190 != RET_SUCCESS) 191 return (RET_ERROR); 192 break; 193 } 194 if (sz == 0) { 195 len = p - t->bt_dbuf; 196 t->bt_dbufsz += (sz = 256); 197 if ((t->bt_dbuf = 198 realloc(t->bt_dbuf, t->bt_dbufsz)) == NULL) 199 return (RET_ERROR); 200 p = t->bt_dbuf + len; 201 } 202 } 203 if (ch == EOF) 204 break; 205 } 206 if (nrec < top) { 207 SET(t, R_EOF); 208 return (RET_SPECIAL); 209 } 210 return (RET_SUCCESS); 211 } 212 213 /* 214 * __REC_FMAP -- Get fixed length records from a file. 215 * 216 * Parameters: 217 * t: tree 218 * cnt: records to read 219 * 220 * Returns: 221 * RET_ERROR, RET_SUCCESS 222 */ 223 int 224 __rec_fmap(t, top) 225 BTREE *t; 226 recno_t top; 227 { 228 DBT data; 229 recno_t nrec; 230 caddr_t sp, ep; 231 size_t len; 232 char *p; 233 234 sp = t->bt_cmap; 235 ep = t->bt_emap; 236 data.data = t->bt_dbuf; 237 data.size = t->bt_reclen; 238 239 if (t->bt_dbufsz < t->bt_reclen) { 240 if ((t->bt_dbuf = realloc(t->bt_dbuf, t->bt_reclen)) == NULL) 241 return (RET_ERROR); 242 t->bt_dbufsz = t->bt_reclen; 243 } 244 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 245 if (sp >= ep) { 246 SET(t, R_EOF); 247 return (RET_SPECIAL); 248 } 249 len = t->bt_reclen; 250 for (p = t->bt_dbuf; sp < ep && len--; *p++ = *sp++); 251 memset(p, t->bt_bval, len); 252 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 253 return (RET_ERROR); 254 } 255 t->bt_cmap = sp; 256 return (RET_SUCCESS); 257 } 258 259 /* 260 * __REC_VMAP -- Get variable length records from a file. 261 * 262 * Parameters: 263 * t: tree 264 * cnt: records to read 265 * 266 * Returns: 267 * RET_ERROR, RET_SUCCESS 268 */ 269 int 270 __rec_vmap(t, top) 271 BTREE *t; 272 recno_t top; 273 { 274 DBT data; 275 caddr_t sp, ep; 276 recno_t nrec; 277 int bval; 278 279 sp = t->bt_cmap; 280 ep = t->bt_emap; 281 bval = t->bt_bval; 282 283 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 284 if (sp >= ep) { 285 SET(t, R_EOF); 286 return (RET_SPECIAL); 287 } 288 for (data.data = sp; sp < ep && *sp != bval; ++sp); 289 data.size = sp - (caddr_t)data.data; 290 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 291 return (RET_ERROR); 292 ++sp; 293 } 294 t->bt_cmap = sp; 295 return (RET_SUCCESS); 296 } 297