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: head/lib/libc/db/recno/rec_get.c 189387 2009-03-05 00:57:01Z delphij $ 31 */ 32 33 #include <sys/types.h> 34 35 #include <errno.h> 36 #include <stddef.h> 37 #include <stdio.h> 38 #include <stdlib.h> 39 #include <string.h> 40 #include <unistd.h> 41 42 #include <db.h> 43 #include "recno.h" 44 45 /* 46 * __REC_GET -- Get a record from the btree. 47 * 48 * Parameters: 49 * dbp: pointer to access method 50 * key: key to find 51 * data: data to return 52 * flag: currently unused 53 * 54 * Returns: 55 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found. 56 */ 57 int 58 __rec_get(const DB *dbp, const DBT *key, DBT *data, unsigned int flags) 59 { 60 BTREE *t; 61 EPG *e; 62 recno_t nrec; 63 int status; 64 65 t = dbp->internal; 66 67 /* Toss any page pinned across calls. */ 68 if (t->bt_pinned != NULL) { 69 mpool_put(t->bt_mp, t->bt_pinned, 0); 70 t->bt_pinned = NULL; 71 } 72 73 /* Get currently doesn't take any flags, and keys of 0 are illegal. */ 74 if (flags || (nrec = *(recno_t *)key->data) == 0) { 75 errno = EINVAL; 76 return (RET_ERROR); 77 } 78 79 /* 80 * If we haven't seen this record yet, try to find it in the 81 * original file. 82 */ 83 if (nrec > t->bt_nrecs) { 84 if (F_ISSET(t, R_EOF | R_INMEM)) 85 return (RET_SPECIAL); 86 if ((status = t->bt_irec(t, nrec)) != RET_SUCCESS) 87 return (status); 88 } 89 90 --nrec; 91 if ((e = __rec_search(t, nrec, SEARCH)) == NULL) 92 return (RET_ERROR); 93 94 status = __rec_ret(t, e, 0, NULL, data); 95 if (F_ISSET(t, B_DB_LOCK)) 96 mpool_put(t->bt_mp, e->page, 0); 97 else 98 t->bt_pinned = e->page; 99 return (status); 100 } 101 102 /* 103 * __REC_FPIPE -- Get fixed length records from a pipe. 104 * 105 * Parameters: 106 * t: tree 107 * cnt: records to read 108 * 109 * Returns: 110 * RET_ERROR, RET_SUCCESS 111 */ 112 int 113 __rec_fpipe(BTREE *t, recno_t top) 114 { 115 DBT data; 116 recno_t nrec; 117 size_t len; 118 int ch; 119 unsigned char *p; 120 121 if (t->bt_rdata.size < t->bt_reclen) { 122 t->bt_rdata.data = reallocf(t->bt_rdata.data, t->bt_reclen); 123 if (t->bt_rdata.data == NULL) 124 return (RET_ERROR); 125 t->bt_rdata.size = t->bt_reclen; 126 } 127 data.data = t->bt_rdata.data; 128 data.size = t->bt_reclen; 129 130 for (nrec = t->bt_nrecs; nrec < top;) { 131 len = t->bt_reclen; 132 for (p = t->bt_rdata.data;; *p++ = ch) 133 if ((ch = getc(t->bt_rfp)) == EOF || !--len) { 134 if (ch != EOF) 135 *p = ch; 136 if (len != 0) 137 memset(p, t->bt_bval, len); 138 if (__rec_iput(t, 139 nrec, &data, 0) != RET_SUCCESS) 140 return (RET_ERROR); 141 ++nrec; 142 break; 143 } 144 if (ch == EOF) 145 break; 146 } 147 if (nrec < top) { 148 F_SET(t, R_EOF); 149 return (RET_SPECIAL); 150 } 151 return (RET_SUCCESS); 152 } 153 154 /* 155 * __REC_VPIPE -- Get variable length records from a pipe. 156 * 157 * Parameters: 158 * t: tree 159 * cnt: records to read 160 * 161 * Returns: 162 * RET_ERROR, RET_SUCCESS 163 */ 164 int 165 __rec_vpipe(BTREE *t, recno_t top) 166 { 167 DBT data; 168 recno_t nrec; 169 size_t len; 170 size_t sz; 171 int bval, ch; 172 unsigned char *p; 173 174 bval = t->bt_bval; 175 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 176 for (p = t->bt_rdata.data, 177 sz = t->bt_rdata.size;; *p++ = ch, --sz) { 178 if ((ch = getc(t->bt_rfp)) == EOF || ch == bval) { 179 data.data = t->bt_rdata.data; 180 data.size = p - 181 (unsigned char *)t->bt_rdata.data; 182 if (ch == EOF && data.size == 0) 183 break; 184 if (__rec_iput(t, nrec, &data, 0) 185 != RET_SUCCESS) 186 return (RET_ERROR); 187 break; 188 } 189 if (sz == 0) { 190 len = p - (unsigned char *)t->bt_rdata.data; 191 t->bt_rdata.size += (sz = 256); 192 t->bt_rdata.data = reallocf(t->bt_rdata.data, 193 t->bt_rdata.size); 194 if (t->bt_rdata.data == NULL) 195 return (RET_ERROR); 196 p = (unsigned char *)t->bt_rdata.data + len; 197 } 198 } 199 if (ch == EOF) 200 break; 201 } 202 if (nrec < top) { 203 F_SET(t, R_EOF); 204 return (RET_SPECIAL); 205 } 206 return (RET_SUCCESS); 207 } 208 209 /* 210 * __REC_FMAP -- Get fixed length records from a file. 211 * 212 * Parameters: 213 * t: tree 214 * cnt: records to read 215 * 216 * Returns: 217 * RET_ERROR, RET_SUCCESS 218 */ 219 int 220 __rec_fmap(BTREE *t, recno_t top) 221 { 222 DBT data; 223 recno_t nrec; 224 unsigned char *sp, *ep, *p; 225 size_t len; 226 227 if (t->bt_rdata.size < t->bt_reclen) { 228 t->bt_rdata.data = reallocf(t->bt_rdata.data, t->bt_reclen); 229 if (t->bt_rdata.data == NULL) 230 return (RET_ERROR); 231 t->bt_rdata.size = t->bt_reclen; 232 } 233 data.data = t->bt_rdata.data; 234 data.size = t->bt_reclen; 235 236 sp = (unsigned char *)t->bt_cmap; 237 ep = (unsigned char *)t->bt_emap; 238 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 239 if (sp >= ep) { 240 F_SET(t, R_EOF); 241 return (RET_SPECIAL); 242 } 243 len = t->bt_reclen; 244 for (p = t->bt_rdata.data; 245 sp < ep && len > 0; *p++ = *sp++, --len); 246 if (len != 0) 247 memset(p, t->bt_bval, len); 248 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 249 return (RET_ERROR); 250 } 251 t->bt_cmap = (caddr_t)sp; 252 return (RET_SUCCESS); 253 } 254 255 /* 256 * __REC_VMAP -- Get variable length records from a file. 257 * 258 * Parameters: 259 * t: tree 260 * cnt: records to read 261 * 262 * Returns: 263 * RET_ERROR, RET_SUCCESS 264 */ 265 int 266 __rec_vmap(BTREE *t, recno_t top) 267 { 268 DBT data; 269 unsigned char *sp, *ep; 270 recno_t nrec; 271 int bval; 272 273 sp = (unsigned char *)t->bt_cmap; 274 ep = (unsigned char *)t->bt_emap; 275 bval = t->bt_bval; 276 277 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 278 if (sp >= ep) { 279 F_SET(t, R_EOF); 280 return (RET_SPECIAL); 281 } 282 for (data.data = sp; sp < ep && *sp != bval; ++sp); 283 data.size = sp - (unsigned char *)data.data; 284 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 285 return (RET_ERROR); 286 ++sp; 287 } 288 t->bt_cmap = (caddr_t)sp; 289 return (RET_SUCCESS); 290 } 291