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. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)rec_get.c 8.9 (Berkeley) 8/18/94 30 * $FreeBSD: src/lib/libc/db/recno/rec_get.c,v 1.2.6.2 2001/01/02 09:11:10 obrien Exp $ 31 * $DragonFly: src/lib/libc/db/recno/rec_get.c,v 1.4 2005/11/12 23:01:55 swildner Exp $ 32 */ 33 34 #include <sys/types.h> 35 36 #include <errno.h> 37 #include <stddef.h> 38 #include <stdio.h> 39 #include <stdlib.h> 40 #include <string.h> 41 #include <unistd.h> 42 43 #include <db.h> 44 #include "recno.h" 45 46 /* 47 * __REC_GET -- Get a record from the btree. 48 * 49 * Parameters: 50 * dbp: pointer to access method 51 * key: key to find 52 * data: data to return 53 * flag: currently unused 54 * 55 * Returns: 56 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found. 57 */ 58 int 59 __rec_get(const DB *dbp, const DBT *key, DBT *data, u_int flags) 60 { 61 BTREE *t; 62 EPG *e; 63 recno_t nrec; 64 int status; 65 66 t = dbp->internal; 67 68 /* Toss any page pinned across calls. */ 69 if (t->bt_pinned != NULL) { 70 mpool_put(t->bt_mp, t->bt_pinned, 0); 71 t->bt_pinned = NULL; 72 } 73 74 /* Get currently doesn't take any flags, and keys of 0 are illegal. */ 75 if (flags || (nrec = *(recno_t *)key->data) == 0) { 76 errno = EINVAL; 77 return (RET_ERROR); 78 } 79 80 /* 81 * If we haven't seen this record yet, try to find it in the 82 * original file. 83 */ 84 if (nrec > t->bt_nrecs) { 85 if (F_ISSET(t, R_EOF | R_INMEM)) 86 return (RET_SPECIAL); 87 if ((status = t->bt_irec(t, nrec)) != RET_SUCCESS) 88 return (status); 89 } 90 91 --nrec; 92 if ((e = __rec_search(t, nrec, SEARCH)) == NULL) 93 return (RET_ERROR); 94 95 status = __rec_ret(t, e, 0, NULL, data); 96 if (F_ISSET(t, B_DB_LOCK)) 97 mpool_put(t->bt_mp, e->page, 0); 98 else 99 t->bt_pinned = e->page; 100 return (status); 101 } 102 103 /* 104 * __REC_FPIPE -- Get fixed length records from a pipe. 105 * 106 * Parameters: 107 * t: tree 108 * cnt: records to read 109 * 110 * Returns: 111 * RET_ERROR, RET_SUCCESS 112 */ 113 int 114 __rec_fpipe(BTREE *t, recno_t top) 115 { 116 DBT data; 117 recno_t nrec; 118 size_t len; 119 int ch; 120 u_char *p; 121 122 if (t->bt_rdata.size < t->bt_reclen) { 123 t->bt_rdata.data = t->bt_rdata.data == NULL ? 124 malloc(t->bt_reclen) : 125 reallocf(t->bt_rdata.data, t->bt_reclen); 126 if (t->bt_rdata.data == NULL) 127 return (RET_ERROR); 128 t->bt_rdata.size = t->bt_reclen; 129 } 130 data.data = t->bt_rdata.data; 131 data.size = t->bt_reclen; 132 133 for (nrec = t->bt_nrecs; nrec < top;) { 134 len = t->bt_reclen; 135 for (p = t->bt_rdata.data;; *p++ = ch) 136 if ((ch = getc(t->bt_rfp)) == EOF || !--len) { 137 if (ch != EOF) 138 *p = ch; 139 if (len != 0) 140 memset(p, t->bt_bval, len); 141 if (__rec_iput(t, 142 nrec, &data, 0) != RET_SUCCESS) 143 return (RET_ERROR); 144 ++nrec; 145 break; 146 } 147 if (ch == EOF) 148 break; 149 } 150 if (nrec < top) { 151 F_SET(t, R_EOF); 152 return (RET_SPECIAL); 153 } 154 return (RET_SUCCESS); 155 } 156 157 /* 158 * __REC_VPIPE -- Get variable length records from a pipe. 159 * 160 * Parameters: 161 * t: tree 162 * cnt: records to read 163 * 164 * Returns: 165 * RET_ERROR, RET_SUCCESS 166 */ 167 int 168 __rec_vpipe(BTREE *t, recno_t top) 169 { 170 DBT data; 171 recno_t nrec; 172 size_t len; 173 size_t sz; 174 int bval, ch; 175 u_char *p; 176 177 bval = t->bt_bval; 178 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 179 for (p = t->bt_rdata.data, 180 sz = t->bt_rdata.size;; *p++ = ch, --sz) { 181 if ((ch = getc(t->bt_rfp)) == EOF || ch == bval) { 182 data.data = t->bt_rdata.data; 183 data.size = p - (u_char *)t->bt_rdata.data; 184 if (ch == EOF && data.size == 0) 185 break; 186 if (__rec_iput(t, nrec, &data, 0) 187 != RET_SUCCESS) 188 return (RET_ERROR); 189 break; 190 } 191 if (sz == 0) { 192 len = p - (u_char *)t->bt_rdata.data; 193 t->bt_rdata.size += (sz = 256); 194 t->bt_rdata.data = t->bt_rdata.data == NULL ? 195 malloc(t->bt_rdata.size) : 196 reallocf(t->bt_rdata.data, t->bt_rdata.size); 197 if (t->bt_rdata.data == NULL) 198 return (RET_ERROR); 199 p = (u_char *)t->bt_rdata.data + len; 200 } 201 } 202 if (ch == EOF) 203 break; 204 } 205 if (nrec < top) { 206 F_SET(t, R_EOF); 207 return (RET_SPECIAL); 208 } 209 return (RET_SUCCESS); 210 } 211 212 /* 213 * __REC_FMAP -- Get fixed length records from a file. 214 * 215 * Parameters: 216 * t: tree 217 * cnt: records to read 218 * 219 * Returns: 220 * RET_ERROR, RET_SUCCESS 221 */ 222 int 223 __rec_fmap(BTREE *t, recno_t top) 224 { 225 DBT data; 226 recno_t nrec; 227 u_char *sp, *ep, *p; 228 size_t len; 229 230 if (t->bt_rdata.size < t->bt_reclen) { 231 t->bt_rdata.data = t->bt_rdata.data == NULL ? 232 malloc(t->bt_reclen) : 233 reallocf(t->bt_rdata.data, t->bt_reclen); 234 if (t->bt_rdata.data == NULL) 235 return (RET_ERROR); 236 t->bt_rdata.size = t->bt_reclen; 237 } 238 data.data = t->bt_rdata.data; 239 data.size = t->bt_reclen; 240 241 sp = (u_char *)t->bt_cmap; 242 ep = (u_char *)t->bt_emap; 243 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 244 if (sp >= ep) { 245 F_SET(t, R_EOF); 246 return (RET_SPECIAL); 247 } 248 len = t->bt_reclen; 249 for (p = t->bt_rdata.data; 250 sp < ep && len > 0; *p++ = *sp++, --len); 251 if (len != 0) 252 memset(p, t->bt_bval, len); 253 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 254 return (RET_ERROR); 255 } 256 t->bt_cmap = (caddr_t)sp; 257 return (RET_SUCCESS); 258 } 259 260 /* 261 * __REC_VMAP -- Get variable length records from a file. 262 * 263 * Parameters: 264 * t: tree 265 * cnt: records to read 266 * 267 * Returns: 268 * RET_ERROR, RET_SUCCESS 269 */ 270 int 271 __rec_vmap(BTREE *t, recno_t top) 272 { 273 DBT data; 274 u_char *sp, *ep; 275 recno_t nrec; 276 int bval; 277 278 sp = (u_char *)t->bt_cmap; 279 ep = (u_char *)t->bt_emap; 280 bval = t->bt_bval; 281 282 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 283 if (sp >= ep) { 284 F_SET(t, R_EOF); 285 return (RET_SPECIAL); 286 } 287 for (data.data = sp; sp < ep && *sp != bval; ++sp); 288 data.size = sp - (u_char *)data.data; 289 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 290 return (RET_ERROR); 291 ++sp; 292 } 293 t->bt_cmap = (caddr_t)sp; 294 return (RET_SUCCESS); 295 } 296