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 1.3 2005/09/19 09:20:37 asmodai 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(dbp, key, data, flags) 60 const DB *dbp; 61 const DBT *key; 62 DBT *data; 63 u_int flags; 64 { 65 BTREE *t; 66 EPG *e; 67 recno_t nrec; 68 int status; 69 70 t = dbp->internal; 71 72 /* Toss any page pinned across calls. */ 73 if (t->bt_pinned != NULL) { 74 mpool_put(t->bt_mp, t->bt_pinned, 0); 75 t->bt_pinned = NULL; 76 } 77 78 /* Get currently doesn't take any flags, and keys of 0 are illegal. */ 79 if (flags || (nrec = *(recno_t *)key->data) == 0) { 80 errno = EINVAL; 81 return (RET_ERROR); 82 } 83 84 /* 85 * If we haven't seen this record yet, try to find it in the 86 * original file. 87 */ 88 if (nrec > t->bt_nrecs) { 89 if (F_ISSET(t, R_EOF | R_INMEM)) 90 return (RET_SPECIAL); 91 if ((status = t->bt_irec(t, nrec)) != RET_SUCCESS) 92 return (status); 93 } 94 95 --nrec; 96 if ((e = __rec_search(t, nrec, SEARCH)) == NULL) 97 return (RET_ERROR); 98 99 status = __rec_ret(t, e, 0, NULL, data); 100 if (F_ISSET(t, B_DB_LOCK)) 101 mpool_put(t->bt_mp, e->page, 0); 102 else 103 t->bt_pinned = e->page; 104 return (status); 105 } 106 107 /* 108 * __REC_FPIPE -- Get fixed length records from a pipe. 109 * 110 * Parameters: 111 * t: tree 112 * cnt: records to read 113 * 114 * Returns: 115 * RET_ERROR, RET_SUCCESS 116 */ 117 int 118 __rec_fpipe(t, top) 119 BTREE *t; 120 recno_t top; 121 { 122 DBT data; 123 recno_t nrec; 124 size_t len; 125 int ch; 126 u_char *p; 127 128 if (t->bt_rdata.size < t->bt_reclen) { 129 t->bt_rdata.data = t->bt_rdata.data == NULL ? 130 malloc(t->bt_reclen) : 131 reallocf(t->bt_rdata.data, t->bt_reclen); 132 if (t->bt_rdata.data == NULL) 133 return (RET_ERROR); 134 t->bt_rdata.size = t->bt_reclen; 135 } 136 data.data = t->bt_rdata.data; 137 data.size = t->bt_reclen; 138 139 for (nrec = t->bt_nrecs; nrec < top;) { 140 len = t->bt_reclen; 141 for (p = t->bt_rdata.data;; *p++ = ch) 142 if ((ch = getc(t->bt_rfp)) == EOF || !--len) { 143 if (ch != EOF) 144 *p = ch; 145 if (len != 0) 146 memset(p, t->bt_bval, len); 147 if (__rec_iput(t, 148 nrec, &data, 0) != RET_SUCCESS) 149 return (RET_ERROR); 150 ++nrec; 151 break; 152 } 153 if (ch == EOF) 154 break; 155 } 156 if (nrec < top) { 157 F_SET(t, R_EOF); 158 return (RET_SPECIAL); 159 } 160 return (RET_SUCCESS); 161 } 162 163 /* 164 * __REC_VPIPE -- Get variable length records from a pipe. 165 * 166 * Parameters: 167 * t: tree 168 * cnt: records to read 169 * 170 * Returns: 171 * RET_ERROR, RET_SUCCESS 172 */ 173 int 174 __rec_vpipe(t, top) 175 BTREE *t; 176 recno_t top; 177 { 178 DBT data; 179 recno_t nrec; 180 size_t len; 181 size_t sz; 182 int bval, ch; 183 u_char *p; 184 185 bval = t->bt_bval; 186 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 187 for (p = t->bt_rdata.data, 188 sz = t->bt_rdata.size;; *p++ = ch, --sz) { 189 if ((ch = getc(t->bt_rfp)) == EOF || ch == bval) { 190 data.data = t->bt_rdata.data; 191 data.size = p - (u_char *)t->bt_rdata.data; 192 if (ch == EOF && data.size == 0) 193 break; 194 if (__rec_iput(t, nrec, &data, 0) 195 != RET_SUCCESS) 196 return (RET_ERROR); 197 break; 198 } 199 if (sz == 0) { 200 len = p - (u_char *)t->bt_rdata.data; 201 t->bt_rdata.size += (sz = 256); 202 t->bt_rdata.data = t->bt_rdata.data == NULL ? 203 malloc(t->bt_rdata.size) : 204 reallocf(t->bt_rdata.data, t->bt_rdata.size); 205 if (t->bt_rdata.data == NULL) 206 return (RET_ERROR); 207 p = (u_char *)t->bt_rdata.data + len; 208 } 209 } 210 if (ch == EOF) 211 break; 212 } 213 if (nrec < top) { 214 F_SET(t, R_EOF); 215 return (RET_SPECIAL); 216 } 217 return (RET_SUCCESS); 218 } 219 220 /* 221 * __REC_FMAP -- Get fixed length records from a file. 222 * 223 * Parameters: 224 * t: tree 225 * cnt: records to read 226 * 227 * Returns: 228 * RET_ERROR, RET_SUCCESS 229 */ 230 int 231 __rec_fmap(t, top) 232 BTREE *t; 233 recno_t top; 234 { 235 DBT data; 236 recno_t nrec; 237 u_char *sp, *ep, *p; 238 size_t len; 239 240 if (t->bt_rdata.size < t->bt_reclen) { 241 t->bt_rdata.data = t->bt_rdata.data == NULL ? 242 malloc(t->bt_reclen) : 243 reallocf(t->bt_rdata.data, t->bt_reclen); 244 if (t->bt_rdata.data == NULL) 245 return (RET_ERROR); 246 t->bt_rdata.size = t->bt_reclen; 247 } 248 data.data = t->bt_rdata.data; 249 data.size = t->bt_reclen; 250 251 sp = (u_char *)t->bt_cmap; 252 ep = (u_char *)t->bt_emap; 253 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 254 if (sp >= ep) { 255 F_SET(t, R_EOF); 256 return (RET_SPECIAL); 257 } 258 len = t->bt_reclen; 259 for (p = t->bt_rdata.data; 260 sp < ep && len > 0; *p++ = *sp++, --len); 261 if (len != 0) 262 memset(p, t->bt_bval, len); 263 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 264 return (RET_ERROR); 265 } 266 t->bt_cmap = (caddr_t)sp; 267 return (RET_SUCCESS); 268 } 269 270 /* 271 * __REC_VMAP -- Get variable length records from a file. 272 * 273 * Parameters: 274 * t: tree 275 * cnt: records to read 276 * 277 * Returns: 278 * RET_ERROR, RET_SUCCESS 279 */ 280 int 281 __rec_vmap(t, top) 282 BTREE *t; 283 recno_t top; 284 { 285 DBT data; 286 u_char *sp, *ep; 287 recno_t nrec; 288 int bval; 289 290 sp = (u_char *)t->bt_cmap; 291 ep = (u_char *)t->bt_emap; 292 bval = t->bt_bval; 293 294 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 295 if (sp >= ep) { 296 F_SET(t, R_EOF); 297 return (RET_SPECIAL); 298 } 299 for (data.data = sp; sp < ep && *sp != bval; ++sp); 300 data.size = sp - (u_char *)data.data; 301 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 302 return (RET_ERROR); 303 ++sp; 304 } 305 t->bt_cmap = (caddr_t)sp; 306 return (RET_SUCCESS); 307 } 308