dwm

Commit: 17d72fecc7d49de2ea0d2c17181308ce2e20ea49
Parent: de6594ba9da43e935254ef9b7b954ea8fbdbf6ef
Author: Randy Palamar
Date:   Tue, 24 Dec 2024 13:19:50 -0700

add custom.c for custom c code

I'm kind of sick of having shell scripts all over the place that
dwm calls. As much as is possible I'm going to be moving those
here where I can use a real programming language that can complete
the task in a fraction of the cpu cycles.

Diffstat:
M
Makefile
 | 
2
+-
A
custom.c
 | 
61
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

2 files changed, 62 insertions(+), 1 deletion(-)
diff --git a/Makefile b/Makefile
@@ -11,7 +11,7 @@ all: dwm
 .c.o:
 	${CC} -c ${CFLAGS} $<
 
-${OBJ}: config.h config.mk
+${OBJ}: config.h config.mk custom.c
 
 config.h:
 	cp config.def.h $@
diff --git a/custom.c b/custom.c
@@ -0,0 +1,61 @@
+#include <fcntl.h>
+
+#define KEYBIND_FN(name) void name(const Arg *a)
+
+#define CLAMP(x, a, b) ((x) < (a) ? (a) : (x) > (b) ? (b) : (x))
+#define CLAMP01(x)     CLAMP(x, 0, 1)
+
+typedef float f32;
+
+struct backlight_arg {
+	const char *backlight; /* /sys/class/backlight/XXX */
+	float       delta;     /* [%] */
+};
+
+static long
+read_long(int fd)
+{
+	char buffer[64];
+	ptrdiff_t rlen = read(fd, buffer, sizeof(buffer));
+	close(fd);
+	if (rlen == -1)
+		return 0;
+	if (rlen >= sizeof(buffer))
+		rlen = sizeof(buffer) - 1;
+	buffer[rlen] = 0;
+	return strtol(buffer, 0, 10);
+}
+
+static KEYBIND_FN(backlight)
+{
+	const struct backlight_arg *ba = a->v;
+	static f32 max_brightness;
+
+	char path[1024];
+	/* NOTE(rnp): this could simplified using the my stream system */
+	if (!max_brightness) {
+		snprintf(path, sizeof(path), "/sys/class/backlight/%s/max_brightness", ba->backlight);
+		int fd = open(path, O_RDONLY);
+		if (fd != -1)
+			max_brightness = read_long(fd);
+	}
+
+	long current_brightness;
+	snprintf(path, sizeof(path), "/sys/class/backlight/%s/brightness", ba->backlight);
+	int fd = open(path, O_RDONLY);
+	if (fd != -1) {
+		current_brightness = read_long(fd);
+		close(fd);
+		fd = open(path, O_WRONLY);
+		if (fd != -1 && max_brightness) {
+			f32 current_percent = 100 * current_brightness / max_brightness;
+			current_percent += ba->delta;
+			current_percent  = CLAMP(current_percent, 1, 100);
+			current_percent /= 100;
+			long len = snprintf(path, sizeof(path), "%ld\n",
+			                    (long)(current_percent * max_brightness));
+			write(fd, path, len);
+			close(fd);
+		}
+	}
+}