diff options
Diffstat (limited to 'xbacklight.c')
| -rw-r--r-- | xbacklight.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/xbacklight.c b/xbacklight.c new file mode 100644 index 0000000..df99905 --- /dev/null +++ b/xbacklight.c @@ -0,0 +1,214 @@ +#include <stdio.h> +#include <stdlib.h> +#include <X11/Xatom.h> +#include <X11/Xlib.h> +#include <X11/extensions/Xrandr.h> + +typedef enum { Get, Set, Inc, Dec } op_t; + +static char *program_name; + +static Atom backlight; + +static void +usage (void) +{ + fprintf(stderr, "usage: %s [options]\n", program_name); + fprintf(stderr, " where options are:\n"); + fprintf(stderr, " -display <display> or -d <display>\n"); + fprintf(stderr, " -help\n"); + fprintf(stderr, " -set <percentage> or = <percentage>\n"); + fprintf(stderr, " -inc <percentage> or + <percentage>\n"); + fprintf(stderr, " -dec <percentage> or - <percentage>\n"); + fprintf(stderr, " -get\n"); + /*NOTREACHED*/ + exit (1); +} + +static long +backlight_get (Display *dpy, RROutput output) +{ + unsigned long nitems; + unsigned long bytes_after; + unsigned char *prop; + Atom actual_type; + int actual_format; + long value; + + if (XRRGetOutputProperty (dpy, output, backlight, + 0, 4, False, False, None, + &actual_type, &actual_format, + &nitems, &bytes_after, &prop) != Success) + return -1; + if (actual_type != XA_INTEGER || nitems != 1 || actual_format != 32) + value = -1; + else + value = *((long *) prop); + XFree (prop); + return value; +} + +static void +backlight_set (Display *dpy, RROutput output, long value) +{ + XRRChangeOutputProperty (dpy, output, backlight, XA_INTEGER, 32, + PropModeReplace, (unsigned char *) &value, 1); +} + +int +main (int argc, char **argv) +{ + char *dpy_name = NULL; + Display *dpy; + int screen; + int major, minor; + op_t op = Get; + int value = 0; + int i; + + program_name = argv[0]; + + for (i = 1; i < argc; i++) + { + if (!strcmp (argv[i], "-display") || !strcmp ("-d", argv[i])) + { + if (++i >= argc) usage(); + dpy_name = argv[i]; + continue; + } + if (!strcmp (argv[i], "-set") || !strcmp (argv[i], "=")) + { + if (++i >= argc) usage(); + op = Set; + value = atoi (argv[i]); + continue; + } + if (argv[i][0] == '=' && isdigit (argv[i][1])) + { + op = Set; + value = atoi (argv[i] + 1); + continue; + } + if (!strcmp (argv[i], "-inc") || !strcmp (argv[i], "+")) + { + if (++i >= argc) usage(); + op = Inc; + value = atoi (argv[i]); + continue; + } + if (argv[i][0] == '+' && isdigit (argv[i][1])) + { + op = Inc; + value = atoi (argv[i] + 1); + continue; + } + if (!strcmp (argv[i], "-dec") || !strcmp (argv[i], "-")) + { + if (++i >= argc) usage(); + op = Dec; + value = atoi (argv[i]); + continue; + } + if (argv[i][0] == '-' && isdigit (argv[i][1])) + { + op = Dec; + value = atoi (argv[i] + 1); + continue; + } + if (!strcmp (argv[i], "-get") || !strcmp (argv[i], "-g")) + { + op = Get; + continue; + } + if (!strcmp (argv[i], "-help") || !strcmp (argv[i], "-?")) + { + usage (); + } + } + dpy = XOpenDisplay (dpy_name); + if (!dpy) + { + fprintf (stderr, "Cannot open display \"%s\"\n", + XDisplayName (dpy_name)); + exit (1); + } + if (!XRRQueryVersion (dpy, &major, &minor)) + { + fprintf (stderr, "RandR extension missing\n"); + exit (1); + } + if (major < 1 || (major == 1 && minor < 2)) + { + fprintf (stderr, "RandR version %d.%d too old\n", major, minor); + exit (1); + } + backlight = XInternAtom (dpy, "BACKLIGHT", True); + if (backlight == None) + { + fprintf (stderr, "No outputs have backlight property\n"); + exit (1); + } + for (screen = 0; screen < ScreenCount (dpy); screen++) + { + Window root = RootWindow (dpy, screen); + XRRScreenResources *resources = XRRGetScreenResources (dpy, root); + int o; + + if (!resources) continue; + for (o = 0; o < resources->noutput; o++) + { + RROutput output = resources->outputs[o]; + XRRPropertyInfo *info; + double cur, new, step; + double min, max; + double set; + + cur = backlight_get (dpy, output); + if (cur != -1) + { + info = XRRQueryOutputProperty (dpy, output, backlight); + if (info) + { + if (info->range && info->num_values == 2) + { + min = info->values[0]; + max = info->values[1]; + if (op == Get) { + printf ("%f\n", (cur - min) * 100 / (max - min)); + } else { + set = value * (max - min) / 100; + switch (op) { + case Set: + new = min + set; + break; + case Inc: + new = cur + set; + break; + case Dec: + new = cur - set; + break; + } + if (new > max) new = max; + if (new < min) new = min; + step = (new - cur) / 50; + for (i = 0; i < 50; i++) + { + if (i == 49) + cur = new; + else + cur += step; + backlight_set (dpy, output, (long) cur); + XFlush (dpy); + usleep (10 * 1000); + } + } + } + XFree (info); + } + } + } + + XRRFreeScreenResources (resources); + } + XSync (dpy, False); +} |