Test fix using correct gpu when multiple gpus are connected

build.sh

@@ -16,7 +16,7 @@ build_gsr_kms_server() {
 }
 
 build_gsr() {
-    dependencies="libavcodec libavformat libavutil x11 xcomposite xrandr xfixes libpulse libswresample libavfilter libva libcap"
+    dependencies="libavcodec libavformat libavutil x11 xcomposite xrandr xfixes libpulse libswresample libavfilter libva libcap libdrm"
     includes="$(pkg-config --cflags $dependencies)"
     libs="$(pkg-config --libs $dependencies) -ldl -pthread -lm"
     $CC -c src/capture/capture.c $opts $includes

project.conf

@@ -20,3 +20,4 @@ libavfilter = ">=5"
 libva = ">=1"
 libcap = ">=2"
 xfixes = ">=2"
+libdrm = ">=2"

src/utils.c

@@ -4,6 +4,8 @@
 #include <string.h>
 #include <stdio.h>
 #include <unistd.h>
+#include <xf86drmMode.h>
+#include <fcntl.h>
 
 double clock_get_monotonic_seconds(void) {
     struct timespec ts;
@@ -109,7 +111,19 @@ bool gl_get_gpu_info(Display *dpy, gsr_gpu_info *info) {
 bool gsr_get_valid_card_path(char *output) {
     for(int i = 0; i < 10; ++i) {
         sprintf(output, "/dev/dri/card%d", i);
-        if(access(output, F_OK) == 0)
+        int fd = open(output, O_RDONLY);
+        if(fd == -1)
+            continue;
+
+        bool is_display_card = false;
+        drmModeResPtr resources = drmModeGetResources(fd);
+        if(resources) {
+            is_display_card = true;
+            drmModeFreeResources(resources);
+        }
+        close(fd);
+
+        if(is_display_card)
             return true;
     }
     return false;