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 = g_malloc0(sizeof(*palette)); 59 palette_init(palette, max, bpp); 60 return palette; 61 } 62 63 void palette_init(VncPalette *palette, size_t max, int bpp) 64 { 65 memset(palette, 0, sizeof (*palette)); 66 palette->max = max; 67 palette->bpp = bpp; 68 } 69 70 void palette_destroy(VncPalette *palette) 71 { 72 g_free(palette); 73 } 74 75 int palette_put(VncPalette *palette, uint32_t color) 76 { 77 unsigned int hash; 78 unsigned int idx = palette->size; 79 VncPaletteEntry *entry; 80 81 hash = palette_hash(color, palette->bpp) % VNC_PALETTE_HASH_SIZE; 82 entry = palette_find(palette, color, hash); 83 84 if (!entry && palette->size >= palette->max) { 85 return 0; 86 } 87 if (!entry) { 88 VncPaletteEntry *entry; 89 90 entry = &palette->pool[palette->size]; 91 entry->color = color; 92 entry->idx = idx; 93 QLIST_INSERT_HEAD(&palette->table[hash], entry, next); 94 palette->size++; 95 } 96 return palette->size; 97 } 98 99 int palette_idx(const VncPalette *palette, uint32_t color) 100 { 101 VncPaletteEntry *entry; 102 unsigned int hash; 103 104 hash = palette_hash(color, palette->bpp) % VNC_PALETTE_HASH_SIZE; 105 entry = palette_find(palette, color, hash); 106 return (entry == NULL ? -1 : entry->idx); 107 } 108 109 size_t palette_size(const VncPalette *palette) 110 { 111 return palette->size; 112 } 113 114 void palette_iter(const VncPalette *palette, 115 void (*iter)(int idx, uint32_t color, void *opaque), 116 void *opaque) 117 { 118 int i; 119 VncPaletteEntry *entry; 120 121 for (i = 0; i < VNC_PALETTE_HASH_SIZE; i++) { 122 QLIST_FOREACH(entry, &palette->table[i], next) { 123 iter(entry->idx, entry->color, opaque); 124 } 125 } 126 } 127 128 uint32_t palette_color(const VncPalette *palette, int idx, bool *found) 129 { 130 int i; 131 VncPaletteEntry *entry; 132 133 for (i = 0; i < VNC_PALETTE_HASH_SIZE; i++) { 134 QLIST_FOREACH(entry, &palette->table[i], next) { 135 if (entry->idx == idx) { 136 *found = true; 137 return entry->color; 138 } 139 } 140 } 141 142 *found = false; 143 return -1; 144 } 145 146 static void palette_fill_cb(int idx, uint32_t color, void *opaque) 147 { 148 uint32_t *colors = opaque; 149 150 colors[idx] = color; 151 } 152 153 size_t palette_fill(const VncPalette *palette, 154 uint32_t colors[VNC_PALETTE_MAX_SIZE]) 155 { 156 palette_iter(palette, palette_fill_cb, colors); 157 return palette_size(palette); 158 } 159