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 #include <glib.h> 31 #include <string.h> 32 33 static VncPaletteEntry *palette_find(const VncPalette *palette, 34 uint32_t color, unsigned int hash) 35 { 36 VncPaletteEntry *entry; 37 38 QLIST_FOREACH(entry, &palette->table[hash], next) { 39 if (entry->color == color) { 40 return entry; 41 } 42 } 43 44 return NULL; 45 } 46 47 static unsigned int palette_hash(uint32_t rgb, int bpp) 48 { 49 if (bpp == 16) { 50 return ((unsigned int)(((rgb >> 8) + rgb) & 0xFF)); 51 } else { 52 return ((unsigned int)(((rgb >> 16) + (rgb >> 8)) & 0xFF)); 53 } 54 } 55 56 VncPalette *palette_new(size_t max, int bpp) 57 { 58 VncPalette *palette; 59 60 palette = g_malloc0(sizeof(*palette)); 61 palette_init(palette, max, bpp); 62 return palette; 63 } 64 65 void palette_init(VncPalette *palette, size_t max, int bpp) 66 { 67 memset(palette, 0, sizeof (*palette)); 68 palette->max = max; 69 palette->bpp = bpp; 70 } 71 72 void palette_destroy(VncPalette *palette) 73 { 74 g_free(palette); 75 } 76 77 int palette_put(VncPalette *palette, uint32_t color) 78 { 79 unsigned int hash; 80 unsigned int idx = palette->size; 81 VncPaletteEntry *entry; 82 83 hash = palette_hash(color, palette->bpp) % VNC_PALETTE_HASH_SIZE; 84 entry = palette_find(palette, color, hash); 85 86 if (!entry && palette->size >= palette->max) { 87 return 0; 88 } 89 if (!entry) { 90 VncPaletteEntry *entry; 91 92 entry = &palette->pool[palette->size]; 93 entry->color = color; 94 entry->idx = idx; 95 QLIST_INSERT_HEAD(&palette->table[hash], entry, next); 96 palette->size++; 97 } 98 return palette->size; 99 } 100 101 int palette_idx(const VncPalette *palette, uint32_t color) 102 { 103 VncPaletteEntry *entry; 104 unsigned int hash; 105 106 hash = palette_hash(color, palette->bpp) % VNC_PALETTE_HASH_SIZE; 107 entry = palette_find(palette, color, hash); 108 return (entry == NULL ? -1 : entry->idx); 109 } 110 111 size_t palette_size(const VncPalette *palette) 112 { 113 return palette->size; 114 } 115 116 void palette_iter(const VncPalette *palette, 117 void (*iter)(int idx, uint32_t color, void *opaque), 118 void *opaque) 119 { 120 int i; 121 VncPaletteEntry *entry; 122 123 for (i = 0; i < VNC_PALETTE_HASH_SIZE; i++) { 124 QLIST_FOREACH(entry, &palette->table[i], next) { 125 iter(entry->idx, entry->color, opaque); 126 } 127 } 128 } 129 130 uint32_t palette_color(const VncPalette *palette, int idx, bool *found) 131 { 132 int i; 133 VncPaletteEntry *entry; 134 135 for (i = 0; i < VNC_PALETTE_HASH_SIZE; i++) { 136 QLIST_FOREACH(entry, &palette->table[i], next) { 137 if (entry->idx == idx) { 138 *found = true; 139 return entry->color; 140 } 141 } 142 } 143 144 *found = false; 145 return -1; 146 } 147 148 static void palette_fill_cb(int idx, uint32_t color, void *opaque) 149 { 150 uint32_t *colors = opaque; 151 152 colors[idx] = color; 153 } 154 155 size_t palette_fill(const VncPalette *palette, 156 uint32_t colors[VNC_PALETTE_MAX_SIZE]) 157 { 158 palette_iter(palette, palette_fill_cb, colors); 159 return palette_size(palette); 160 } 161