1 /* $NetBSD: rec_get.c,v 1.18 2013/12/25 19:42:23 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #if HAVE_NBTOOL_CONFIG_H 33 #include "nbtool_config.h" 34 #endif 35 36 #include <sys/cdefs.h> 37 __RCSID("$NetBSD: rec_get.c,v 1.18 2013/12/25 19:42:23 christos Exp $"); 38 39 #include "namespace.h" 40 #include <sys/types.h> 41 42 #include <assert.h> 43 #include <errno.h> 44 #include <stddef.h> 45 #include <stdio.h> 46 #include <stdlib.h> 47 #include <string.h> 48 #include <unistd.h> 49 50 #include <db.h> 51 #include "recno.h" 52 53 /* 54 * __REC_GET -- Get a record from the btree. 55 * 56 * Parameters: 57 * dbp: pointer to access method 58 * key: key to find 59 * data: data to return 60 * flag: currently unused 61 * 62 * Returns: 63 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found. 64 */ 65 int 66 __rec_get(const DB *dbp, const DBT *key, DBT *data, u_int flags) 67 { 68 BTREE *t; 69 EPG *e; 70 recno_t nrec; 71 int status; 72 73 t = dbp->internal; 74 75 /* Toss any page pinned across calls. */ 76 if (t->bt_pinned != NULL) { 77 mpool_put(t->bt_mp, t->bt_pinned, 0); 78 t->bt_pinned = NULL; 79 } 80 81 /* Get currently doesn't take any flags, and keys of 0 are illegal. */ 82 if (flags || (nrec = *(recno_t *)key->data) == 0) { 83 errno = EINVAL; 84 return (RET_ERROR); 85 } 86 87 /* 88 * If we haven't seen this record yet, try to find it in the 89 * original file. 90 */ 91 if (nrec > t->bt_nrecs) { 92 if (F_ISSET(t, R_EOF | R_INMEM)) 93 return (RET_SPECIAL); 94 if ((status = t->bt_irec(t, nrec)) != RET_SUCCESS) 95 return (status); 96 } 97 98 --nrec; 99 if ((e = __rec_search(t, nrec, SEARCH)) == NULL) 100 return (RET_ERROR); 101 102 status = __rec_ret(t, e, 0, NULL, data); 103 if (F_ISSET(t, B_DB_LOCK)) 104 mpool_put(t->bt_mp, e->page, 0); 105 else 106 t->bt_pinned = e->page; 107 return (status); 108 } 109 110 /* 111 * __REC_FPIPE -- Get fixed length records from a pipe. 112 * 113 * Parameters: 114 * t: tree 115 * cnt: records to read 116 * 117 * Returns: 118 * RET_ERROR, RET_SUCCESS 119 */ 120 int 121 __rec_fpipe(BTREE *t, recno_t top) 122 { 123 DBT data; 124 recno_t nrec; 125 size_t len; 126 int ch; 127 uint8_t *p; 128 129 if (t->bt_rdata.size < t->bt_reclen) { 130 void *np = realloc(t->bt_rdata.data, t->bt_reclen); 131 if (np == NULL) 132 return (RET_ERROR); 133 t->bt_rdata.data = np; 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(BTREE *t, recno_t top) 175 { 176 DBT data; 177 recno_t nrec; 178 size_t sz; 179 int bval, ch; 180 uint8_t *p; 181 182 bval = t->bt_bval; 183 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 184 for (p = t->bt_rdata.data, 185 sz = t->bt_rdata.size;; *p++ = ch, --sz) { 186 if ((ch = getc(t->bt_rfp)) == EOF || ch == bval) { 187 data.data = t->bt_rdata.data; 188 data.size = p - (uint8_t *)t->bt_rdata.data; 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 ptrdiff_t len = p - (uint8_t *)t->bt_rdata.data; 198 size_t tot = t->bt_rdata.size + (sz = 256); 199 void *np = realloc(t->bt_rdata.data, tot); 200 if (np == NULL) 201 return (RET_ERROR); 202 t->bt_rdata.size = tot; 203 t->bt_rdata.data = np; 204 p = (uint8_t *)t->bt_rdata.data + len; 205 } 206 } 207 if (ch == EOF) 208 break; 209 } 210 if (nrec < top) { 211 F_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(BTREE *t, recno_t top) 229 { 230 DBT data; 231 recno_t nrec; 232 uint8_t *sp, *ep, *p; 233 size_t len; 234 235 if (t->bt_rdata.size < t->bt_reclen) { 236 void *np = realloc(t->bt_rdata.data, t->bt_reclen); 237 if (np == NULL) 238 return (RET_ERROR); 239 t->bt_rdata.data = np; 240 t->bt_rdata.size = t->bt_reclen; 241 } 242 data.data = t->bt_rdata.data; 243 data.size = t->bt_reclen; 244 245 sp = (uint8_t *)t->bt_cmap; 246 ep = (uint8_t *)t->bt_emap; 247 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 248 if (sp >= ep) { 249 F_SET(t, R_EOF); 250 return (RET_SPECIAL); 251 } 252 len = t->bt_reclen; 253 for (p = t->bt_rdata.data; 254 sp < ep && len > 0; *p++ = *sp++, --len); 255 if (len != 0) 256 memset(p, t->bt_bval, len); 257 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 258 return (RET_ERROR); 259 } 260 t->bt_cmap = (caddr_t)sp; 261 return (RET_SUCCESS); 262 } 263 264 /* 265 * __REC_VMAP -- Get variable length records from a file. 266 * 267 * Parameters: 268 * t: tree 269 * cnt: records to read 270 * 271 * Returns: 272 * RET_ERROR, RET_SUCCESS 273 */ 274 int 275 __rec_vmap(BTREE *t, recno_t top) 276 { 277 DBT data; 278 uint8_t *sp, *ep; 279 recno_t nrec; 280 int bval; 281 282 sp = (uint8_t *)t->bt_cmap; 283 ep = (uint8_t *)t->bt_emap; 284 bval = t->bt_bval; 285 286 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 287 if (sp >= ep) { 288 F_SET(t, R_EOF); 289 return (RET_SPECIAL); 290 } 291 for (data.data = sp; sp < ep && *sp != bval; ++sp); 292 data.size = sp - (uint8_t *)data.data; 293 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 294 return (RET_ERROR); 295 ++sp; 296 } 297 t->bt_cmap = (caddr_t)sp; 298 return (RET_SUCCESS); 299 } 300
Indexes created Sat Sep 20 22:09:52 GMT 2025