seatd/common/drm.c

#include <string.h>
#include <sys/ioctl.h>
#include <sys/types.h>

#include "drm.h"

// From libdrm
#define DRM_IOCTL_BASE        'd'
#define DRM_IO(nr)            _IO(DRM_IOCTL_BASE, nr)
#define DRM_IOCTL_SET_MASTER  DRM_IO(0x1e)
#define DRM_IOCTL_DROP_MASTER DRM_IO(0x1f)

#define STRLEN(s)                 ((sizeof(s) / sizeof(s[0])) - 1)
#define STR_HAS_PREFIX(prefix, s) (strncmp(prefix, s, STRLEN(prefix)) == 0)

int drm_set_master(int fd) {
	return ioctl(fd, DRM_IOCTL_SET_MASTER, 0);
}

int drm_drop_master(int fd) {
	return ioctl(fd, DRM_IOCTL_DROP_MASTER, 0);
}

#if defined(__linux__) || defined(__NetBSD__)
int path_is_drm(const char *path) {
	if (STR_HAS_PREFIX("/dev/dri/", path))
		return 1;
	return 0;
}
#elif defined(__FreeBSD__)
int path_is_drm(const char *path) {
	if (STR_HAS_PREFIX("/dev/dri/", path))
		return 1;
	/* Some drivers have /dev/dri/X symlinked to /dev/drm/X */
	if (STR_HAS_PREFIX("/dev/drm/", path))
		return 1;
	return 0;
}
#else
#error Unsupported platform
#endif