1 files changed, 163 insertions, 0 deletions
diff --git a/autorotate.c b/autorotate.c
new file mode 100644
index 0000000..7cdfddf
--- /dev/null
+++ b/autorotate.c
@@ -0,0 +1,163 @@
+#define _XOPEN_SOURCE 700
+#include <sys/select.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#define ACPID_SOCK_PATH "/var/run/acpid.socket"
+
+/* once to go into tablet mode, twice to come out */
+#define ACPI_ROTATE	"ibm/hotkey LEN0068:00 00000080 000060c0\n"
+
+/* once on keydown, once on keyup */
+#define ACPI_ROTATELOCK	"ibm/hotkey LEN0068:00 00000080 00006020\n"
+
+#define FIXME_HARDCODED_DEV_NUMBER 4
+
+#define GRAVITY_CUTOFF	(7.0)
+#define DEV_PATH	"/sys/bus/iio/devices/iio:device%d"
+#define SCALE_FILE	"in_accel_scale"
+#define X_RAW_FILE	"in_accel_x_raw"
+#define Y_RAW_FILE	"in_accel_y_raw"
+
+int tabletmode = 0;
+int rotatelock = 0;
+enum { NORMAL, LEFT, INVERTED, RIGHT } rotation = NORMAL;
+
+int openacpi(const char *path)
+{
+	struct sockaddr_un sun = {0};
+	int sock = socket(AF_UNIX, SOCK_STREAM, 0);
+	if (sock == -1) {
+		return -1;
+	}
+
+	sun.sun_family = AF_UNIX;
+	strcpy(sun.sun_path, path ? path : ACPID_SOCK_PATH);
+	if (connect(sock, (const struct sockaddr*)&sun, sizeof(sun)) == -1) {
+		close(sock);
+		return -1;
+	}
+
+	return sock;
+}
+
+void checkacpi(int acpi)
+{
+	static int nrotate = 0;
+	static int nlock = 0;
+
+	char buf[BUFSIZ];
+	ssize_t n = read(acpi, buf, sizeof(buf));
+	if (n <= 0) {
+		return;
+	}
+
+	if (!strcmp(buf, ACPI_ROTATE)) {
+		nrotate++;
+		if (nrotate == 1) {
+			printf("Entering tablet mode\n");
+			tabletmode = 1;
+		} else if (nrotate == 3) {
+			printf("Leaving tablet mode\n");
+			tabletmode = 0;
+			nrotate = 0;
+		}
+	} else if (!strcmp(buf, ACPI_ROTATELOCK)) {
+		nlock++;
+		if (nlock == 2) {
+			nlock = 0;
+			rotatelock = ! rotatelock;
+			printf("Set rotate lock to %d\n", rotatelock);
+		}
+	}
+}
+
+FILE *opendevfile(const char *file)
+{
+	static char devdir[sizeof(DEV_PATH) + 5] = { '\0' };
+	char *path = NULL;
+	if (devdir[0] == '\0') {
+		sprintf(devdir, DEV_PATH, FIXME_HARDCODED_DEV_NUMBER);
+	}
+	path = malloc(strlen(devdir) + strlen(file) + 4);
+	sprintf(path, "%s/%s", devdir, file);
+	FILE *dev = fopen(path, "r");
+	free(path);
+	return dev;
+}
+
+
+double getgravity(double cutoff)
+{
+	FILE *scale = opendevfile(SCALE_FILE);
+
+	if (scale == NULL) {
+		return cutoff;
+	}
+
+	double scalefactor;
+	fscanf(scale, "%lf", &scalefactor);
+	fclose(scale);
+
+	return cutoff / scalefactor;
+}
+
+double getraw(const char *file)
+{
+	double value = 0.0;
+	FILE *raw = opendevfile(file);
+	if (raw) {
+		fscanf(raw, "%lg", &value);
+		fclose(raw);
+	}
+	return value;
+}
+
+int main(void)
+{
+	double gravity = getgravity(GRAVITY_CUTOFF);
+
+	printf("Grativational cutoff is %lf\n", gravity);
+	int acpi = openacpi(NULL);
+	if (acpi == -1) {
+		tabletmode = 1;
+		rotatelock = 0;
+		rotation = NORMAL;
+	}
+
+	for (;;) {
+		int nfds = 0;
+		fd_set fds = acpi + 1;
+		FD_ZERO(&fds);
+		struct timeval to = {0};
+		to.tv_usec = 5000;
+		int forever = 0;
+
+		if (acpi != -1) {
+			FD_SET(acpi, &fds);
+			if (tabletmode == 0 || rotatelock == 1) {
+				forever = 1;
+			}
+		}
+
+		select(nfds, &fds, NULL, NULL, forever ? NULL : &to);
+
+		if (acpi != -1 && FD_ISSET(acpi, &fds)) {
+			checkacpi(acpi);
+		}
+
+		if (tabletmode == 1 && rotatelock == 0) {
+			double x = getraw(X_RAW_FILE);
+			double y = getraw(Y_RAW_FILE);
+			printf("X: %lg; Y: %lg\n", x, y);
+		} else {
+			printf("Not rotating because tabletmode is %d and rotatelock is %d\n", tabletmode, rotatelock);
+		}
+	}
+
+	return 1;
+}