rec_get.c revision 1.7
1 /* $NetBSD: rec_get.c,v 1.7 1995/02/27 13:24:57 cgd 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #if defined(LIBC_SCCS) && !defined(lint) 37 #if 0 38 static char sccsid[] = "@(#)rec_get.c 8.5 (Berkeley) 6/20/94"; 39 #else 40 static char rcsid[] = "$NetBSD: rec_get.c,v 1.7 1995/02/27 13:24:57 cgd Exp $"; 41 #endif 42 #endif /* LIBC_SCCS and not lint */ 43 44 #include <sys/types.h> 45 46 #include <errno.h> 47 #include <stddef.h> 48 #include <stdio.h> 49 #include <stdlib.h> 50 #include <string.h> 51 #include <unistd.h> 52 53 #include <db.h> 54 #include "recno.h" 55 56 /* 57 * __REC_GET -- Get a record from the btree. 58 * 59 * Parameters: 60 * dbp: pointer to access method 61 * key: key to find 62 * data: data to return 63 * flag: currently unused 64 * 65 * Returns: 66 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found. 67 */ 68 int 69 __rec_get(dbp, key, data, flags) 70 const DB *dbp; 71 const DBT *key; 72 DBT *data; 73 u_int flags; 74 { 75 BTREE *t; 76 EPG *e; 77 recno_t nrec; 78 int status; 79 80 t = dbp->internal; 81 82 /* Toss any page pinned across calls. */ 83 if (t->bt_pinned != NULL) { 84 mpool_put(t->bt_mp, t->bt_pinned, 0); 85 t->bt_pinned = NULL; 86 } 87 88 /* Get currently doesn't take any flags, and keys of 0 are illegal. */ 89 if (flags || (nrec = *(recno_t *)key->data) == 0) { 90 errno = EINVAL; 91 return (RET_ERROR); 92 } 93 94 /* 95 * If we haven't seen this record yet, try to find it in the 96 * original file. 97 */ 98 if (nrec > t->bt_nrecs) { 99 if (ISSET(t, R_EOF | R_INMEM)) 100 return (RET_SPECIAL); 101 if ((status = t->bt_irec(t, nrec)) != RET_SUCCESS) 102 return (status); 103 } 104 105 --nrec; 106 if ((e = __rec_search(t, nrec, SEARCH)) == NULL) 107 return (RET_ERROR); 108 109 status = __rec_ret(t, e, 0, NULL, data); 110 if (ISSET(t, B_DB_LOCK)) 111 mpool_put(t->bt_mp, e->page, 0); 112 else 113 t->bt_pinned = e->page; 114 return (status); 115 } 116 117 /* 118 * __REC_FPIPE -- Get fixed length records from a pipe. 119 * 120 * Parameters: 121 * t: tree 122 * cnt: records to read 123 * 124 * Returns: 125 * RET_ERROR, RET_SUCCESS 126 */ 127 int 128 __rec_fpipe(t, top) 129 BTREE *t; 130 recno_t top; 131 { 132 DBT data; 133 recno_t nrec; 134 size_t len; 135 int ch; 136 char *p; 137 138 if (t->bt_dbufsz < t->bt_reclen) { 139 t->bt_dbuf = (char *)(t->bt_dbuf == NULL ? 140 malloc(t->bt_reclen) : realloc(t->bt_dbuf, t->bt_reclen)); 141 if (t->bt_dbuf == NULL) 142 return (RET_ERROR); 143 t->bt_dbufsz = t->bt_reclen; 144 } 145 data.data = t->bt_dbuf; 146 data.size = t->bt_reclen; 147 148 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 149 len = t->bt_reclen; 150 for (p = t->bt_dbuf;; *p++ = ch) 151 if ((ch = getc(t->bt_rfp)) == EOF || !len--) { 152 if (__rec_iput(t, nrec, &data, 0) 153 != RET_SUCCESS) 154 return (RET_ERROR); 155 break; 156 } 157 if (ch == EOF) 158 break; 159 } 160 if (nrec < top) { 161 SET(t, R_EOF); 162 return (RET_SPECIAL); 163 } 164 return (RET_SUCCESS); 165 } 166 167 /* 168 * __REC_VPIPE -- Get variable length records from a pipe. 169 * 170 * Parameters: 171 * t: tree 172 * cnt: records to read 173 * 174 * Returns: 175 * RET_ERROR, RET_SUCCESS 176 */ 177 int 178 __rec_vpipe(t, top) 179 BTREE *t; 180 recno_t top; 181 { 182 DBT data; 183 recno_t nrec; 184 indx_t len; 185 size_t sz; 186 int bval, ch; 187 char *p; 188 189 bval = t->bt_bval; 190 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 191 for (p = t->bt_dbuf, sz = t->bt_dbufsz;; *p++ = ch, --sz) { 192 if ((ch = getc(t->bt_rfp)) == EOF || ch == bval) { 193 data.data = t->bt_dbuf; 194 data.size = p - t->bt_dbuf; 195 if (ch == EOF && data.size == 0) 196 break; 197 if (__rec_iput(t, nrec, &data, 0) 198 != RET_SUCCESS) 199 return (RET_ERROR); 200 break; 201 } 202 if (sz == 0) { 203 len = p - t->bt_dbuf; 204 t->bt_dbufsz += (sz = 256); 205 t->bt_dbuf = (char *)(t->bt_dbuf == NULL ? 206 malloc(t->bt_dbufsz) : 207 realloc(t->bt_dbuf, t->bt_dbufsz)); 208 if (t->bt_dbuf == NULL) 209 return (RET_ERROR); 210 p = t->bt_dbuf + len; 211 } 212 } 213 if (ch == EOF) 214 break; 215 } 216 if (nrec < top) { 217 SET(t, R_EOF); 218 return (RET_SPECIAL); 219 } 220 return (RET_SUCCESS); 221 } 222 223 /* 224 * __REC_FMAP -- Get fixed length records from a file. 225 * 226 * Parameters: 227 * t: tree 228 * cnt: records to read 229 * 230 * Returns: 231 * RET_ERROR, RET_SUCCESS 232 */ 233 int 234 __rec_fmap(t, top) 235 BTREE *t; 236 recno_t top; 237 { 238 DBT data; 239 recno_t nrec; 240 caddr_t sp, ep; 241 size_t len; 242 char *p; 243 244 if (t->bt_dbufsz < t->bt_reclen) { 245 t->bt_dbuf = (char *)(t->bt_dbuf == NULL ? 246 malloc(t->bt_reclen) : realloc(t->bt_dbuf, t->bt_reclen)); 247 if (t->bt_dbuf == NULL) 248 return (RET_ERROR); 249 t->bt_dbufsz = t->bt_reclen; 250 } 251 data.data = t->bt_dbuf; 252 data.size = t->bt_reclen; 253 254 sp = t->bt_cmap; 255 ep = t->bt_emap; 256 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 257 if (sp >= ep) { 258 SET(t, R_EOF); 259 return (RET_SPECIAL); 260 } 261 len = t->bt_reclen; 262 for (p = t->bt_dbuf; sp < ep && len--; *p++ = *sp++); 263 memset(p, t->bt_bval, len); 264 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 265 return (RET_ERROR); 266 } 267 t->bt_cmap = sp; 268 return (RET_SUCCESS); 269 } 270 271 /* 272 * __REC_VMAP -- Get variable length records from a file. 273 * 274 * Parameters: 275 * t: tree 276 * cnt: records to read 277 * 278 * Returns: 279 * RET_ERROR, RET_SUCCESS 280 */ 281 int 282 __rec_vmap(t, top) 283 BTREE *t; 284 recno_t top; 285 { 286 DBT data; 287 caddr_t sp, ep; 288 recno_t nrec; 289 int bval; 290 291 sp = t->bt_cmap; 292 ep = t->bt_emap; 293 bval = t->bt_bval; 294 295 for (nrec = t->bt_nrecs; nrec < top; ++nrec) { 296 if (sp >= ep) { 297 SET(t, R_EOF); 298 return (RET_SPECIAL); 299 } 300 for (data.data = sp; sp < ep && *sp != bval; ++sp); 301 data.size = sp - (caddr_t)data.data; 302 if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS) 303 return (RET_ERROR); 304 ++sp; 305 } 306 t->bt_cmap = sp; 307 return (RET_SUCCESS); 308 } 309
Indexes created Sun Oct 19 02:09:48 GMT 2025