1 /* 2 * QEMU VNC display driver: palette hash table 3 * 4 * From libvncserver/libvncserver/tight.c 5 * Copyright (C) 2000, 2001 Const Kaplinsky. All Rights Reserved. 6 * Copyright (C) 1999 AT&T Laboratories Cambridge. All Rights Reserved. 7 * 8 * Copyright (C) 2010 Corentin Chary <corentin.chary@gmail.com> 9 * 10 * Permission is hereby granted, free of charge, to any person obtaining a copy 11 * of this software and associated documentation files (the "Software"), to deal 12 * in the Software without restriction, including without limitation the rights 13 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 14 * copies of the Software, and to permit persons to whom the Software is 15 * furnished to do so, subject to the following conditions: 16 * 17 * The above copyright notice and this permission notice shall be included in 18 * all copies or substantial portions of the Software. 19 * 20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 23 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 25 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 26 * THE SOFTWARE. 27 */ 28 29 #include "vnc-palette.h" 30 31 static VncPaletteEntry *palette_find(const VncPalette *palette, 32 uint32_t color, unsigned int hash) 33 { 34 VncPaletteEntry *entry; 35 36 QLIST_FOREACH(entry, &palette->table[hash], next) { 37 if (entry->color == color) { 38 return entry; 39 } 40 } 41 42 return NULL; 43 } 44 45 static unsigned int palette_hash(uint32_t rgb, int bpp) 46 { 47 if (bpp == 16) { 48 return ((unsigned int)(((rgb >> 8) + rgb) & 0xFF)); 49 } else { 50 return ((unsigned int)(((rgb >> 16) + (rgb >> 8)) & 0xFF)); 51 } 52 } 53 54 VncPalette *palette_new(size_t max, int bpp) 55 { 56 VncPalette *palette; 57 58 palette = qemu_mallocz(sizeof(*palette)); 59 palette->max = max; 60 palette->bpp = bpp; 61 return palette; 62 } 63 64 void palette_destroy(VncPalette *palette) 65 { 66 int i; 67 68 if (palette == NULL) { 69 return ; 70 } 71 72 for (i = 0; i < VNC_PALETTE_HASH_SIZE; i++) { 73 VncPaletteEntry *entry = QLIST_FIRST(&palette->table[i]); 74 while (entry) { 75 VncPaletteEntry *tmp = QLIST_NEXT(entry, next); 76 QLIST_REMOVE(entry, next); 77 qemu_free(entry); 78 entry = tmp; 79 } 80 } 81 82 qemu_free(palette); 83 } 84 85 int palette_put(VncPalette *palette, uint32_t color) 86 { 87 unsigned int hash; 88 unsigned int idx = palette->size; 89 VncPaletteEntry *entry; 90 91 hash = palette_hash(color, palette->bpp) % VNC_PALETTE_HASH_SIZE; 92 entry = palette_find(palette, color, hash); 93 94 if (!entry && palette->size >= palette->max) { 95 return 0; 96 } 97 if (!entry) { 98 VncPaletteEntry *entry; 99 100 entry = qemu_mallocz(sizeof(*entry)); 101 entry->color = color; 102 entry->idx = idx; 103 QLIST_INSERT_HEAD(&palette->table[hash], entry, next); 104 palette->size++; 105 } 106 return palette->size; 107 } 108 109 int palette_idx(const VncPalette *palette, uint32_t color) 110 { 111 VncPaletteEntry *entry; 112 unsigned int hash; 113 114 hash = palette_hash(color, palette->bpp) % VNC_PALETTE_HASH_SIZE; 115 entry = palette_find(palette, color, hash); 116 return (entry == NULL ? -1 : entry->idx); 117 } 118 119 size_t palette_size(const VncPalette *palette) 120 { 121 return palette->size; 122 } 123 124 void palette_iter(const VncPalette *palette, 125 void (*iter)(int idx, uint32_t color, void *opaque), 126 void *opaque) 127 { 128 int i; 129 VncPaletteEntry *entry; 130 131 for (i = 0; i < VNC_PALETTE_HASH_SIZE; i++) { 132 QLIST_FOREACH(entry, &palette->table[i], next) { 133 iter(entry->idx, entry->color, opaque); 134 } 135 } 136 } 137