1 | /*- |
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2 | * Copyright (c) 1990, 1993, 1994 |
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3 | * The Regents of the University of California. All rights reserved. |
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4 | * |
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5 | * Redistribution and use in source and binary forms, with or without |
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6 | * modification, are permitted provided that the following conditions |
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7 | * are met: |
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8 | * 1. Redistributions of source code must retain the above copyright |
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9 | * notice, this list of conditions and the following disclaimer. |
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10 | * 2. Redistributions in binary form must reproduce the above copyright |
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11 | * notice, this list of conditions and the following disclaimer in the |
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12 | * documentation and/or other materials provided with the distribution. |
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13 | * 4. Neither the name of the University nor the names of its contributors |
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14 | * may be used to endorse or promote products derived from this software |
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15 | * without specific prior written permission. |
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16 | * |
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17 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
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18 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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19 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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20 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
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21 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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22 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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23 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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24 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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25 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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26 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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27 | * SUCH DAMAGE. |
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28 | */ |
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29 | |
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30 | #if defined(LIBC_SCCS) && !defined(lint) |
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31 | static char sccsid[] = "@(#)bt_page.c 8.3 (Berkeley) 7/14/94"; |
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32 | #endif /* LIBC_SCCS and not lint */ |
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33 | #include <sys/cdefs.h> |
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34 | __FBSDID("$FreeBSD$"); |
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35 | |
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36 | #include <rtems/bsd/sys/types.h> |
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37 | |
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38 | #include <stdio.h> |
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39 | |
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40 | #include <db.h> |
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41 | #include "btree.h" |
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42 | |
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43 | /* |
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44 | * __bt_free -- |
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45 | * Put a page on the freelist. |
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46 | * |
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47 | * Parameters: |
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48 | * t: tree |
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49 | * h: page to free |
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50 | * |
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51 | * Returns: |
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52 | * RET_ERROR, RET_SUCCESS |
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53 | * |
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54 | * Side-effect: |
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55 | * mpool_put's the page. |
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56 | */ |
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57 | int |
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58 | __bt_free(BTREE *t, PAGE *h) |
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59 | { |
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60 | /* Insert the page at the head of the free list. */ |
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61 | h->prevpg = P_INVALID; |
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62 | h->nextpg = t->bt_free; |
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63 | t->bt_free = h->pgno; |
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64 | F_SET(t, B_METADIRTY); |
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65 | |
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66 | /* Make sure the page gets written back. */ |
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67 | return (mpool_put(t->bt_mp, h, MPOOL_DIRTY)); |
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68 | } |
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69 | |
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70 | /* |
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71 | * __bt_new -- |
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72 | * Get a new page, preferably from the freelist. |
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73 | * |
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74 | * Parameters: |
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75 | * t: tree |
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76 | * npg: storage for page number. |
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77 | * |
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78 | * Returns: |
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79 | * Pointer to a page, NULL on error. |
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80 | */ |
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81 | PAGE * |
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82 | __bt_new(BTREE *t, pgno_t *npg) |
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83 | { |
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84 | PAGE *h; |
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85 | |
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86 | if (t->bt_free != P_INVALID && |
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87 | (h = mpool_get(t->bt_mp, t->bt_free, 0)) != NULL) { |
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88 | *npg = t->bt_free; |
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89 | t->bt_free = h->nextpg; |
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90 | F_SET(t, B_METADIRTY); |
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91 | return (h); |
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92 | } |
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93 | return (mpool_new(t->bt_mp, npg, MPOOL_PAGE_NEXT)); |
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94 | } |
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