projects / mirror_frr.git / blame
| Commit | Line | Data |
|---|---|---|
| a94eca09 MS |
1 | /* |
| 2 | * FRR ID Number Allocator | |
| 3 | * Copyright (C) 2018 Amazon.com, Inc. or its affiliates | |
| 4 | * | |
| 5 | * This program is free software; you can redistribute it and/or modify it | |
| 6 | * under the terms of the GNU General Public License as published by the Free | |
| 7 | * Software Foundation; either version 2 of the License, or (at your option) | |
| 8 | * any later version. | |
| 9 | * | |
| 10 | * This program is distributed in the hope that it will be useful, but WITHOUT | |
| 11 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 12 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
| 13 | * more details. | |
| 14 | * | |
| 15 | * You should have received a copy of the GNU General Public License along | |
| 16 | * with this program; see the file COPYING; if not, write to the Free Software | |
| 17 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
| 18 | */ | |
| 19 | ||
| 20 | #ifndef _ZEBRA_ID_ALLOC_H | |
| 21 | #define _ZEBRA_ID_ALLOC_H | |
| 22 | ||
| 23 | #include <strings.h> | |
| 24 | #include <limits.h> | |
| 25 | #include <stdint.h> | |
| 26 | ||
| 27 | #define IDALLOC_INVALID 0 | |
| 28 | ||
| 29 | #define IDALLOC_DIR_BITS 8 | |
| 30 | #define IDALLOC_SUBDIR_BITS 7 | |
| 31 | #define IDALLOC_PAGE_BITS 7 | |
| 32 | #define IDALLOC_WORD_BITS 5 | |
| 33 | #define IDALLOC_OFFSET_BITS 5 | |
| 34 | ||
| 35 | #define IDALLOC_DIR_COUNT (1 << IDALLOC_DIR_BITS) | |
| 36 | #define IDALLOC_SUBDIR_COUNT (1 << IDALLOC_SUBDIR_BITS) | |
| 37 | #define IDALLOC_PAGE_COUNT (1 << IDALLOC_PAGE_BITS) | |
| 38 | #define IDALLOC_WORD_COUNT (1 << IDALLOC_WORD_BITS) | |
| 39 | ||
| 40 | struct id_alloc_page { | |
| 41 | /* Bitmask of allocations. 1s indicates the ID is already allocated. */ | |
| 42 | uint32_t allocated_mask[IDALLOC_WORD_COUNT]; | |
| 43 | ||
| 44 | /* Bitmask for free space in allocated_mask. 1s indicate whole 32 bit | |
| 45 | * section is full. | |
| 46 | */ | |
| 47 | uint32_t full_word_mask; | |
| 48 | ||
| 49 | /* The ID that bit 0 in allocated_mask corresponds to. */ | |
| 50 | uint32_t base_value; | |
| 51 | ||
| 52 | struct id_alloc_page | |
| 53 | *next_has_free; /* Next page with at least one bit open */ | |
| 54 | }; | |
| 55 | ||
| 56 | struct id_alloc_subdir { | |
| 57 | struct id_alloc_page *sublevels[IDALLOC_PAGE_COUNT]; | |
| 58 | }; | |
| 59 | ||
| 60 | struct id_alloc_dir { | |
| 61 | struct id_alloc_subdir *sublevels[IDALLOC_SUBDIR_COUNT]; | |
| 62 | }; | |
| 63 | ||
| 64 | struct id_alloc { | |
| 65 | struct id_alloc_dir *sublevels[IDALLOC_DIR_COUNT]; | |
| 66 | ||
| 67 | struct id_alloc_page *has_free; | |
| 68 | ||
| 69 | char *name; | |
| 70 | ||
| 71 | uint32_t allocated, capacity; | |
| 72 | }; | |
| 73 | ||
| 74 | struct id_alloc_pool { | |
| 75 | struct id_alloc_pool *next; | |
| 76 | uint32_t id; | |
| 77 | }; | |
| 78 | ||
| 79 | void idalloc_free(struct id_alloc *alloc, uint32_t id); | |
| 80 | void idalloc_free_to_pool(struct id_alloc_pool **pool_ptr, uint32_t id); | |
| 81 | void idalloc_drain_pool(struct id_alloc *alloc, | |
| 82 | struct id_alloc_pool **pool_ptr); | |
| 83 | uint32_t idalloc_allocate(struct id_alloc *alloc); | |
| 84 | uint32_t idalloc_allocate_prefer_pool(struct id_alloc *alloc, | |
| 85 | struct id_alloc_pool **pool_ptr); | |
| 86 | uint32_t idalloc_reserve(struct id_alloc *alloc, uint32_t id); | |
| 87 | struct id_alloc *idalloc_new(const char *name); | |
| 88 | void idalloc_destroy(struct id_alloc *alloc); | |
| 89 | ||
| 90 | #endif |