| 1 | /* Repeating a memory blob, with alias mapping optimization. |
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| 2 | Copyright (C) 2018-2022 Free Software Foundation, Inc. |
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| 3 | This file is part of the GNU C Library. |
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| 4 | |
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| 5 | The GNU C Library is free software; you can redistribute it and/or |
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| 6 | modify it under the terms of the GNU Lesser General Public |
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| 7 | License as published by the Free Software Foundation; either |
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| 8 | version 2.1 of the License, or (at your option) any later version. |
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| 9 | |
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| 10 | The GNU C Library is distributed in the hope that it will be useful, |
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| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 13 | Lesser General Public License for more details. |
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| 14 | |
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| 15 | You should have received a copy of the GNU Lesser General Public |
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| 16 | License along with the GNU C Library; if not, see |
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| 17 | <https://www.gnu.org/licenses/>. */ |
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| 18 | |
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| 19 | #ifndef SUPPORT_BLOB_REPEAT_H |
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| 20 | #define SUPPORT_BLOB_REPEAT_H |
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| 21 | |
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| 22 | #include <stdbool.h> |
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| 23 | #include <stddef.h> |
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| 24 | |
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| 25 | struct support_blob_repeat |
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| 26 | { |
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| 27 | void *start; |
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| 28 | size_t size; |
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| 29 | bool use_malloc; |
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| 30 | }; |
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| 31 | |
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| 32 | /* Return an allocation of COUNT elements, each of ELEMENT_SIZE bytes, |
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| 33 | initialized with the bytes starting at ELEMENT. The memory is |
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| 34 | writable (and thus counts towards the commit charge). In case of |
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| 35 | on error, all members of the return struct are zero-initialized, |
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| 36 | and errno is set accordingly. */ |
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| 37 | struct support_blob_repeat support_blob_repeat_allocate (const void *element, |
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| 38 | size_t element_size, |
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| 39 | size_t count); |
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| 40 | |
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| 41 | /* Like support_blob_repeat_allocate, except that copy-on-write |
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| 42 | semantics are disabled. This means writing to one part of the blob |
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| 43 | can affect other parts. It is possible to map non-shared memory |
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| 44 | over parts of the resulting blob using MAP_ANONYMOUS | MAP_FIXED |
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| 45 | | MAP_PRIVATE, so that writes to these parts do not affect |
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| 46 | others. */ |
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| 47 | struct support_blob_repeat support_blob_repeat_allocate_shared |
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| 48 | (const void *element, size_t element_size, size_t count); |
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| 49 | |
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| 50 | /* Deallocate the blob created by support_blob_repeat_allocate or |
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| 51 | support_blob_repeat_allocate_shared. */ |
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| 52 | void support_blob_repeat_free (struct support_blob_repeat *); |
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| 53 | |
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| 54 | #endif /* SUPPORT_BLOB_REPEAT_H */ |
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| 55 | |
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