color.c

   1 /*
   2  * color.c - color functions
   3  *
   4  * Copyright © 2008-2009 Julien Danjou <julien@danjou.info>
   5  * Copyright © 2009 Uli Schlachter <psychon@znc.in>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  */
  22
  23 #include <ctype.h>
  24
  25 #include "color.h"
  26 #include "globalconf.h"
  27 #include "common/xutil.h"
  28
  29 #define RGB_8TO16(i)   (0xffff * ((i) & 0xff) / 0xff)
  30 #define RGB_16TO8(i)   (0xff * ((i) & 0xffff) / 0xffff)
  31
  32 /** Parse an hexadecimal color string to its component.
  33  * \param colstr The color string.
  34  * \param len The color string length.
  35  * \param red A pointer to the red color to fill.
  36  * \param green A pointer to the green color to fill.
  37  * \param blue A pointer to the blue color to fill.
  38  * \return True if everything alright.
  39  */
  40 static bool
  41 color_parse(const char *colstr, ssize_t len,
  42             uint8_t *red, uint8_t *green, uint8_t *blue)
  43 {
  44     unsigned long colnum;
  45     char *p;
  46
  47     colnum = strtoul(colstr + 1, &p, 16);
  48     if(len != 7 || (p - colstr) != 7 || colstr[0] != '#')
  49     {
  50         warn("awesome: error, invalid color '%s'", colstr);
  51         return false;
  52     }
  53
  54     *red   = (colnum >> 16) & 0xff;
  55     *green = (colnum >> 8) & 0xff;
  56     *blue  = colnum & 0xff;
  57
  58     return true;
  59 }
  60
  61 /** Send a request to initialize a X color.
  62  * If you are only interested in the rgba values and don't need the color's
  63  * pixel value, you should use color_init_unchecked() instead.
  64  * \param color color_t struct to store color into.
  65  * \param colstr Color specification.
  66  * \param len The length of colstr (which still MUST be NULL terminated).
  67  * \return request informations.
  68  */
  69 color_init_request_t
  70 color_init_unchecked(color_t *color, const char *colstr, ssize_t len)
  71 {
  72     color_init_request_t req;
  73     uint8_t red, green, blue;
  74
  75     p_clear(&req, 1);
  76
  77     if(!len)
  78     {
  79         req.has_error = true;
  80         return req;
  81     }
  82
  83     req.color = color;
  84
  85     /* The color is given in RGB value */
  86     if(!color_parse(colstr, len, &red, &green, &blue))
  87     {
  88         warn("awesome: error, invalid color '%s'", colstr);
  89         req.has_error = true;
  90         return req;
  91     }
  92
  93     req.cookie_hexa = xcb_alloc_color_unchecked(globalconf.connection,
  94                                                 globalconf.default_cmap,
  95                                                 RGB_8TO16(red),
  96                                                 RGB_8TO16(green),
  97                                                 RGB_8TO16(blue));
  98
  99     req.has_error = false;
 100     req.colstr = colstr;
 101
 102     return req;
 103 }
 104
 105 /** Initialize a X color.
 106  * \param req color_init request.
 107  * \return True if color allocation was successful.
 108  */
 109 bool
 110 color_init_reply(color_init_request_t req)
 111 {
 112     if(req.has_error)
 113         return false;
 114
 115     xcb_alloc_color_reply_t *hexa_color;
 116
 117     if((hexa_color = xcb_alloc_color_reply(globalconf.connection,
 118                                            req.cookie_hexa, NULL)))
 119     {
 120         req.color->pixel = hexa_color->pixel;
 121         req.color->red   = hexa_color->red;
 122         req.color->green = hexa_color->green;
 123         req.color->blue  = hexa_color->blue;
 124         req.color->initialized = true;
 125         p_delete(&hexa_color);
 126         return true;
 127     }
 128
 129     warn("awesome: error, cannot allocate color '%s'", req.colstr);
 130     return false;
 131 }
 132
 133 /** Push a color as a string onto the stack
 134  * \param L The Lua VM state.
 135  * \param c The color to push.
 136  * \return The number of elements pushed on stack.
 137  */
 138 int
 139 luaA_pushcolor(lua_State *L, const color_t c)
 140 {
 141     uint8_t r = (unsigned) c.red   * 0xff / 0xffff;
 142     uint8_t g = (unsigned) c.green * 0xff / 0xffff;
 143     uint8_t b = (unsigned) c.blue  * 0xff / 0xffff;
 144     char s[10];
 145     int len = snprintf(s, sizeof(s), "#%02x%02x%02x", r, g, b);
 146     lua_pushlstring(L, s, len);
 147     return 1;
 148 }
 149
 150 // vim: filetype=c:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=80