rec_get.c revision 68455
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) 35static char sccsid[] = "@(#)rec_get.c 8.9 (Berkeley) 8/18/94"; 36#endif /* LIBC_SCCS and not lint */ 37 38#if !defined(lint) 39static char rcsid[] = "@(#)$FreeBSD: head/lib/libc/db/recno/rec_get.c 68455 2000-11-07 22:19:23Z obrien $"; 40#endif 41 42#include <sys/types.h> 43 44#include <errno.h> 45#include <stddef.h> 46#include <stdio.h> 47#include <stdlib.h> 48#include <string.h> 49#include <unistd.h> 50 51#include <db.h> 52#include "recno.h" 53 54/* 55 * __REC_GET -- Get a record from the btree. 56 * 57 * Parameters: 58 * dbp: pointer to access method 59 * key: key to find 60 * data: data to return 61 * flag: currently unused 62 * 63 * Returns: 64 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found. 65 */ 66int 67__rec_get(dbp, key, data, flags) 68 const DB *dbp; 69 const DBT *key; 70 DBT *data; 71 u_int flags; 72{ 73 BTREE *t; 74 EPG *e; 75 recno_t nrec; 76 int status; 77 78 t = dbp->internal; 79 80 /* Toss any page pinned across calls. */ 81 if (t->bt_pinned != NULL) { 82 mpool_put(t->bt_mp, t->bt_pinned, 0); 83 t->bt_pinned = NULL; 84 } 85 86 /* Get currently doesn't take any flags, and keys of 0 are illegal. */ 87 if (flags || (nrec = *(recno_t *)key->data) == 0) { 88 errno = EINVAL; 89 return (RET_ERROR); 90 } 91 92 /* 93 * If we haven't seen this record yet, try to find it in the 94 * original file. 95 */ 96 if (nrec > t->bt_nrecs) { 97 if (F_ISSET(t, R_EOF | R_INMEM)) 98 return (RET_SPECIAL); 99 if ((status = t->bt_irec(t, nrec)) != RET_SUCCESS) 100 return (status); 101 } 102 103 --nrec; 104 if ((e = __rec_search(t, nrec, SEARCH)) == NULL) 105 return (RET_ERROR); 106 107 status = __rec_ret(t, e, 0, NULL, data); 108 if (F_ISSET(t, B_DB_LOCK)) 109 mpool_put(t->bt_mp, e->page, 0); 110 else 111 t->bt_pinned = e->page; 112 return (status); 113} 114 115/* 116 * __REC_FPIPE -- Get fixed length records from a pipe. 117 * 118 * Parameters: 119 * t: tree 120 * cnt: records to read 121 * 122 * Returns: 123 * RET_ERROR, RET_SUCCESS 124 */ 125int 126__rec_fpipe(t, top) 127 BTREE *t; 128 recno_t top; 129{ 130 DBT data; 131 recno_t nrec; 132 size_t len; 133 int ch; 134 u_char *p; 135 136 if (t->bt_rdata.size < t->bt_reclen) { 137 t->bt_rdata.data = t->bt_rdata.data == NULL ? 138 malloc(t->bt_reclen) : 139 reallocf(t->bt_rdata.data, t->bt_reclen); 140 if (t->bt_rdata.data == NULL) 141 return (RET_ERROR); 142 t->bt_rdata.size = t->bt_reclen; 143 } 144 data.data = t->bt_rdata.data; 145 data.size = t->bt_reclen; 146 147 for (nrec = t->bt_nrecs; nrec < top;) { 148 len = t->bt_reclen; 149 for (p = t->bt_rdata.data;; *p++ = ch) 150 if ((ch = getc(t->bt_rfp)) == EOF || !--len) { 151 if (ch != EOF) 152 *p = ch; 153 if (len != 0) 154 memset(p, t->bt_bval, len); 155 if (__rec_iput(t, 156 nrec, &data, 0) != RET_SUCCESS) 157 return (RET_ERROR); 158 ++nrec; 159 break; 160 } 161 if (ch == EOF) 162 break; 163 } 164 if (nrec < top) { 165 F_SET(t, R_EOF); 166 return (RET_SPECIAL); 167 } 168 return (RET_SUCCESS); 169} 170 171/* 172 * __REC_VPIPE -- Get variable length records from a pipe. 173 * 174 * Parameters: 175 * t: tree 176 * cnt: records to read 177 * 178 * Returns: 179 * RET_ERROR, RET_SUCCESS 180 */ 181int 182__rec_vpipe(t, top) 183 BTREE *t; 184 recno_t top; 185{ 186 DBT data; 187 recno_t nrec; 188 size_t len; 189 size_t sz; 190 int bval, ch; 191 u_char *p; 192 193 bval = t->bt_bval; 194 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 195 for (p = t->bt_rdata.data, 196 sz = t->bt_rdata.size;; *p++ = ch, --sz) { 197 if ((ch = getc(t->bt_rfp)) == EOF || ch == bval) { 198 data.data = t->bt_rdata.data; 199 data.size = p - (u_char *)t->bt_rdata.data; 200 if (ch == EOF && data.size == 0) 201 break; 202 if (__rec_iput(t, nrec, &data, 0) 203 != RET_SUCCESS) 204 return (RET_ERROR); 205 break; 206 } 207 if (sz == 0) { 208 len = p - (u_char *)t->bt_rdata.data; 209 t->bt_rdata.size += (sz = 256); 210 t->bt_rdata.data = t->bt_rdata.data == NULL ? 211 malloc(t->bt_rdata.size) : 212 reallocf(t->bt_rdata.data, t->bt_rdata.size); 213 if (t->bt_rdata.data == NULL) 214 return (RET_ERROR); 215 p = (u_char *)t->bt_rdata.data + len; 216 } 217 } 218 if (ch == EOF) 219 break; 220 } 221 if (nrec < top) { 222 F_SET(t, R_EOF); 223 return (RET_SPECIAL); 224 } 225 return (RET_SUCCESS); 226} 227 228/* 229 * __REC_FMAP -- Get fixed length records from a file. 230 * 231 * Parameters: 232 * t: tree 233 * cnt: records to read 234 * 235 * Returns: 236 * RET_ERROR, RET_SUCCESS 237 */ 238int 239__rec_fmap(t, top) 240 BTREE *t; 241 recno_t top; 242{ 243 DBT data; 244 recno_t nrec; 245 u_char *sp, *ep, *p; 246 size_t len; 247 248 if (t->bt_rdata.size < t->bt_reclen) { 249 t->bt_rdata.data = t->bt_rdata.data == NULL ? 250 malloc(t->bt_reclen) : 251 reallocf(t->bt_rdata.data, t->bt_reclen); 252 if (t->bt_rdata.data == NULL) 253 return (RET_ERROR); 254 t->bt_rdata.size = t->bt_reclen; 255 } 256 data.data = t->bt_rdata.data; 257 data.size = t->bt_reclen; 258 259 sp = (u_char *)t->bt_cmap; 260 ep = (u_char *)t->bt_emap; 261 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 262 if (sp >= ep) { 263 F_SET(t, R_EOF); 264 return (RET_SPECIAL); 265 } 266 len = t->bt_reclen; 267 for (p = t->bt_rdata.data; 268 sp < ep && len > 0; *p++ = *sp++, --len); 269 if (len != 0) 270 memset(p, t->bt_bval, len); 271 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 272 return (RET_ERROR); 273 } 274 t->bt_cmap = (caddr_t)sp; 275 return (RET_SUCCESS); 276} 277 278/* 279 * __REC_VMAP -- Get variable length records from a file. 280 * 281 * Parameters: 282 * t: tree 283 * cnt: records to read 284 * 285 * Returns: 286 * RET_ERROR, RET_SUCCESS 287 */ 288int 289__rec_vmap(t, top) 290 BTREE *t; 291 recno_t top; 292{ 293 DBT data; 294 u_char *sp, *ep; 295 recno_t nrec; 296 int bval; 297 298 sp = (u_char *)t->bt_cmap; 299 ep = (u_char *)t->bt_emap; 300 bval = t->bt_bval; 301 302 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 303 if (sp >= ep) { 304 F_SET(t, R_EOF); 305 return (RET_SPECIAL); 306 } 307 for (data.data = sp; sp < ep && *sp != bval; ++sp); 308 data.size = sp - (u_char *)data.data; 309 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 310 return (RET_ERROR); 311 ++sp; 312 } 313 t->bt_cmap = (caddr_t)sp; 314 return (RET_SUCCESS); 315} 316