1 | #include <machine/rtems-bsd-user-space.h> |
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2 | |
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3 | /*- |
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4 | * Copyright (c) 1991, 1993, 1994 |
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5 | * The Regents of the University of California. All rights reserved. |
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6 | * |
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7 | * Redistribution and use in source and binary forms, with or without |
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8 | * modification, are permitted provided that the following conditions |
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9 | * are met: |
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10 | * 1. Redistributions of source code must retain the above copyright |
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11 | * notice, this list of conditions and the following disclaimer. |
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12 | * 2. Redistributions in binary form must reproduce the above copyright |
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13 | * notice, this list of conditions and the following disclaimer in the |
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14 | * documentation and/or other materials provided with the distribution. |
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15 | * 4. Neither the name of the University nor the names of its contributors |
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16 | * may be used to endorse or promote products derived from this software |
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17 | * without specific prior written permission. |
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18 | * |
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19 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
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20 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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21 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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22 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
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23 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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24 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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25 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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26 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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27 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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28 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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29 | * SUCH DAMAGE. |
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30 | */ |
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31 | |
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32 | #include <sys/cdefs.h> |
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33 | #ifndef lint |
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34 | /* XXX use __SCCSID */ |
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35 | static char sccsid[] __unused = "@(#)rec_seq.c 8.3 (Berkeley) 7/14/94"; |
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36 | #endif /* not lint */ |
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37 | __FBSDID("$FreeBSD$"); |
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38 | |
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39 | #include <sys/types.h> |
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40 | |
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41 | #include <errno.h> |
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42 | #include <limits.h> |
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43 | #include <stdio.h> |
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44 | #include <string.h> |
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45 | |
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46 | #include <db.h> |
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47 | #include "recno.h" |
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48 | |
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49 | /* |
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50 | * __REC_SEQ -- Recno sequential scan interface. |
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51 | * |
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52 | * Parameters: |
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53 | * dbp: pointer to access method |
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54 | * key: key for positioning and return value |
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55 | * data: data return value |
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56 | * flags: R_CURSOR, R_FIRST, R_LAST, R_NEXT, R_PREV. |
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57 | * |
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58 | * Returns: |
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59 | * RET_ERROR, RET_SUCCESS or RET_SPECIAL if there's no next key. |
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60 | */ |
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61 | int |
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62 | __rec_seq(const DB *dbp, DBT *key, DBT *data, u_int flags) |
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63 | { |
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64 | BTREE *t; |
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65 | EPG *e; |
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66 | recno_t nrec; |
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67 | int status; |
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68 | |
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69 | t = dbp->internal; |
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70 | |
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71 | /* Toss any page pinned across calls. */ |
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72 | if (t->bt_pinned != NULL) { |
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73 | mpool_put(t->bt_mp, t->bt_pinned, 0); |
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74 | t->bt_pinned = NULL; |
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75 | } |
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76 | |
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77 | switch(flags) { |
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78 | case R_CURSOR: |
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79 | if ((nrec = *(recno_t *)key->data) == 0) |
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80 | goto einval; |
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81 | break; |
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82 | case R_NEXT: |
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83 | if (F_ISSET(&t->bt_cursor, CURS_INIT)) { |
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84 | nrec = t->bt_cursor.rcursor + 1; |
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85 | break; |
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86 | } |
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87 | /* FALLTHROUGH */ |
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88 | case R_FIRST: |
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89 | nrec = 1; |
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90 | break; |
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91 | case R_PREV: |
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92 | if (F_ISSET(&t->bt_cursor, CURS_INIT)) { |
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93 | if ((nrec = t->bt_cursor.rcursor - 1) == 0) |
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94 | return (RET_SPECIAL); |
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95 | break; |
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96 | } |
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97 | /* FALLTHROUGH */ |
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98 | case R_LAST: |
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99 | if (!F_ISSET(t, R_EOF | R_INMEM) && |
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100 | t->bt_irec(t, MAX_REC_NUMBER) == RET_ERROR) |
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101 | return (RET_ERROR); |
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102 | nrec = t->bt_nrecs; |
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103 | break; |
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104 | default: |
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105 | einval: errno = EINVAL; |
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106 | return (RET_ERROR); |
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107 | } |
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108 | |
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109 | if (t->bt_nrecs == 0 || nrec > t->bt_nrecs) { |
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110 | if (!F_ISSET(t, R_EOF | R_INMEM) && |
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111 | (status = t->bt_irec(t, nrec)) != RET_SUCCESS) |
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112 | return (status); |
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113 | if (t->bt_nrecs == 0 || nrec > t->bt_nrecs) |
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114 | return (RET_SPECIAL); |
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115 | } |
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116 | |
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117 | if ((e = __rec_search(t, nrec - 1, SEARCH)) == NULL) |
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118 | return (RET_ERROR); |
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119 | |
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120 | F_SET(&t->bt_cursor, CURS_INIT); |
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121 | t->bt_cursor.rcursor = nrec; |
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122 | |
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123 | status = __rec_ret(t, e, nrec, key, data); |
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124 | if (F_ISSET(t, B_DB_LOCK)) |
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125 | mpool_put(t->bt_mp, e->page, 0); |
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126 | else |
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127 | t->bt_pinned = e->page; |
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128 | return (status); |
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129 | } |
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