1 /*- 2 * Copyright (c) 1990, 1993, 1994 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 static char sccsid[] = "@(#)rec_get.c 8.5 (Berkeley) 6/20/94"; 36 #endif /* LIBC_SCCS and not lint */ 37 38 #include <sys/types.h> 39 40 #include <errno.h> 41 #include <stddef.h> 42 #include <stdio.h> 43 #include <stdlib.h> 44 #include <string.h> 45 #include <unistd.h> 46 47 #include <db.h> 48 #include "recno.h" 49 50 /* 51 * __REC_GET -- Get a record from the btree. 52 * 53 * Parameters: 54 * dbp: pointer to access method 55 * key: key to find 56 * data: data to return 57 * flag: currently unused 58 * 59 * Returns: 60 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found. 61 */ 62 int 63 __rec_get(dbp, key, data, flags) 64 const DB *dbp; 65 const DBT *key; 66 DBT *data; 67 u_int flags; 68 { 69 BTREE *t; 70 EPG *e; 71 recno_t nrec; 72 int status; 73 74 t = dbp->internal; 75 76 /* Toss any page pinned across calls. */ 77 if (t->bt_pinned != NULL) { 78 mpool_put(t->bt_mp, t->bt_pinned, 0); 79 t->bt_pinned = NULL; 80 } 81 82 /* Get currently doesn't take any flags, and keys of 0 are illegal. */ 83 if (flags || (nrec = *(recno_t *)key->data) == 0) { 84 errno = EINVAL; 85 return (RET_ERROR); 86 } 87 88 /* 89 * If we haven't seen this record yet, try to find it in the 90 * original file. 91 */ 92 if (nrec > t->bt_nrecs) { 93 if (ISSET(t, R_EOF | R_INMEM)) 94 return (RET_SPECIAL); 95 if ((status = t->bt_irec(t, nrec)) != RET_SUCCESS) 96 return (status); 97 } 98 99 --nrec; 100 if ((e = __rec_search(t, nrec, SEARCH)) == NULL) 101 return (RET_ERROR); 102 103 status = __rec_ret(t, e, 0, NULL, data); 104 if (ISSET(t, B_DB_LOCK)) 105 mpool_put(t->bt_mp, e->page, 0); 106 else 107 t->bt_pinned = e->page; 108 return (status); 109 } 110 111 /* 112 * __REC_FPIPE -- Get fixed length records from a pipe. 113 * 114 * Parameters: 115 * t: tree 116 * cnt: records to read 117 * 118 * Returns: 119 * RET_ERROR, RET_SUCCESS 120 */ 121 int 122 __rec_fpipe(t, top) 123 BTREE *t; 124 recno_t top; 125 { 126 DBT data; 127 recno_t nrec; 128 size_t len; 129 int ch; 130 char *p; 131 132 if (t->bt_dbufsz < t->bt_reclen) { 133 t->bt_dbuf = (char *)(t->bt_dbuf == NULL ? 134 malloc(t->bt_reclen) : realloc(t->bt_dbuf, t->bt_reclen)); 135 if (t->bt_dbuf == NULL) 136 return (RET_ERROR); 137 t->bt_dbufsz = t->bt_reclen; 138 } 139 data.data = t->bt_dbuf; 140 data.size = t->bt_reclen; 141 142 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 143 len = t->bt_reclen; 144 for (p = t->bt_dbuf;; *p++ = ch) 145 if ((ch = getc(t->bt_rfp)) == EOF || !len--) { 146 if (__rec_iput(t, nrec, &data, 0) 147 != RET_SUCCESS) 148 return (RET_ERROR); 149 break; 150 } 151 if (ch == EOF) 152 break; 153 } 154 if (nrec < top) { 155 SET(t, R_EOF); 156 return (RET_SPECIAL); 157 } 158 return (RET_SUCCESS); 159 } 160 161 /* 162 * __REC_VPIPE -- Get variable length records from a pipe. 163 * 164 * Parameters: 165 * t: tree 166 * cnt: records to read 167 * 168 * Returns: 169 * RET_ERROR, RET_SUCCESS 170 */ 171 int 172 __rec_vpipe(t, top) 173 BTREE *t; 174 recno_t top; 175 { 176 DBT data; 177 recno_t nrec; 178 indx_t len; 179 size_t sz; 180 int bval, ch; 181 char *p; 182 183 bval = t->bt_bval; 184 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 185 for (p = t->bt_dbuf, sz = t->bt_dbufsz;; *p++ = ch, --sz) { 186 if ((ch = getc(t->bt_rfp)) == EOF || ch == bval) { 187 data.data = t->bt_dbuf; 188 data.size = p - t->bt_dbuf; 189 if (ch == EOF && data.size == 0) 190 break; 191 if (__rec_iput(t, nrec, &data, 0) 192 != RET_SUCCESS) 193 return (RET_ERROR); 194 break; 195 } 196 if (sz == 0) { 197 len = p - t->bt_dbuf; 198 t->bt_dbufsz += (sz = 256); 199 t->bt_dbuf = (char *)(t->bt_dbuf == NULL ? 200 malloc(t->bt_dbufsz) : 201 realloc(t->bt_dbuf, t->bt_dbufsz)); 202 if (t->bt_dbuf == NULL) 203 return (RET_ERROR); 204 p = t->bt_dbuf + len; 205 } 206 } 207 if (ch == EOF) 208 break; 209 } 210 if (nrec < top) { 211 SET(t, R_EOF); 212 return (RET_SPECIAL); 213 } 214 return (RET_SUCCESS); 215 } 216 217 /* 218 * __REC_FMAP -- Get fixed length records from a file. 219 * 220 * Parameters: 221 * t: tree 222 * cnt: records to read 223 * 224 * Returns: 225 * RET_ERROR, RET_SUCCESS 226 */ 227 int 228 __rec_fmap(t, top) 229 BTREE *t; 230 recno_t top; 231 { 232 DBT data; 233 recno_t nrec; 234 caddr_t sp, ep; 235 size_t len; 236 char *p; 237 238 if (t->bt_dbufsz < t->bt_reclen) { 239 t->bt_dbuf = (char *)(t->bt_dbuf == NULL ? 240 malloc(t->bt_reclen) : realloc(t->bt_dbuf, t->bt_reclen)); 241 if (t->bt_dbuf == NULL) 242 return (RET_ERROR); 243 t->bt_dbufsz = t->bt_reclen; 244 } 245 data.data = t->bt_dbuf; 246 data.size = t->bt_reclen; 247 248 sp = t->bt_cmap; 249 ep = t->bt_emap; 250 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 251 if (sp >= ep) { 252 SET(t, R_EOF); 253 return (RET_SPECIAL); 254 } 255 len = t->bt_reclen; 256 for (p = t->bt_dbuf; sp < ep && len--; *p++ = *sp++); 257 memset(p, t->bt_bval, len); 258 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 259 return (RET_ERROR); 260 } 261 t->bt_cmap = sp; 262 return (RET_SUCCESS); 263 } 264 265 /* 266 * __REC_VMAP -- Get variable length records from a file. 267 * 268 * Parameters: 269 * t: tree 270 * cnt: records to read 271 * 272 * Returns: 273 * RET_ERROR, RET_SUCCESS 274 */ 275 int 276 __rec_vmap(t, top) 277 BTREE *t; 278 recno_t top; 279 { 280 DBT data; 281 caddr_t sp, ep; 282 recno_t nrec; 283 int bval; 284 285 sp = t->bt_cmap; 286 ep = t->bt_emap; 287 bval = t->bt_bval; 288 289 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 290 if (sp >= ep) { 291 SET(t, R_EOF); 292 return (RET_SPECIAL); 293 } 294 for (data.data = sp; sp < ep && *sp != bval; ++sp); 295 data.size = sp - (caddr_t)data.data; 296 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 297 return (RET_ERROR); 298 ++sp; 299 } 300 t->bt_cmap = sp; 301 return (RET_SUCCESS); 302 } 303