From bc15a8f60028539690cccdb78eed7fc9175fe792 Mon Sep 17 00:00:00 2001
From: thejch <66577496+thejch@users.noreply.github.com>
Date: Fri, 15 Mar 2024 07:28:14 -0700
Subject: [PATCH] renderer: Allow headless mode in hyprland (#4794)

* allow headless

* clang-format

* fix redundant logic lol
---
 src/Compositor.cpp      | 25 +++++++++++++++++++------
 src/render/Renderer.cpp | 18 +++++++++++-------
 2 files changed, 30 insertions(+), 13 deletions(-)

diff --git a/src/Compositor.cpp b/src/Compositor.cpp
index eda5b5ed..42ba9b5f 100644
--- a/src/Compositor.cpp
+++ b/src/Compositor.cpp
@@ -127,13 +127,26 @@ void CCompositor::initServer() {
         throwError("wlr_backend_autocreate() failed!");
     }
 
-    m_iDRMFD = wlr_backend_get_drm_fd(m_sWLRBackend);
-    if (m_iDRMFD < 0) {
-        Debug::log(CRIT, "Couldn't query the DRM FD!");
-        throwError("wlr_backend_get_drm_fd() failed!");
-    }
+    bool isHeadlessOnly = true;
+    wlr_multi_for_each_backend(
+        m_sWLRBackend,
+        [](wlr_backend* backend, void* isHeadlessOnly) {
+            if (!wlr_backend_is_headless(backend))
+                *(bool*)isHeadlessOnly = false;
+        },
+        &isHeadlessOnly);
 
-    m_sWLRRenderer = wlr_gles2_renderer_create_with_drm_fd(m_iDRMFD);
+    if (isHeadlessOnly) {
+        m_sWLRRenderer = wlr_renderer_autocreate(m_sWLRBackend);
+    } else {
+        m_iDRMFD = wlr_backend_get_drm_fd(m_sWLRBackend);
+        if (m_iDRMFD < 0) {
+            Debug::log(CRIT, "Couldn't query the DRM FD!");
+            throwError("wlr_backend_get_drm_fd() failed!");
+        }
+
+        m_sWLRRenderer = wlr_gles2_renderer_create_with_drm_fd(m_iDRMFD);
+    }
 
     if (!m_sWLRRenderer) {
         Debug::log(CRIT, "m_sWLRRenderer was NULL! This usually means wlroots could not find a GPU or enountered some issues.");
diff --git a/src/render/Renderer.cpp b/src/render/Renderer.cpp
index a9c7c11a..10f15a9d 100644
--- a/src/render/Renderer.cpp
+++ b/src/render/Renderer.cpp
@@ -31,16 +31,20 @@ CHyprRenderer::CHyprRenderer() {
     } else {
         Debug::log(LOG, "m_sWLRSession is null, omitting full DRM node checks");
 
-        const auto  DRMV = drmGetVersion(g_pCompositor->m_iDRMFD);
+        const auto DRMV = drmGetVersion(g_pCompositor->m_iDRMFD);
 
-        std::string name = std::string{DRMV->name, DRMV->name_len};
-        std::transform(name.begin(), name.end(), name.begin(), tolower);
+        if (DRMV) {
+            std::string name = std::string{DRMV->name, DRMV->name_len};
+            std::transform(name.begin(), name.end(), name.begin(), tolower);
 
-        if (name.contains("nvidia"))
-            m_bNvidia = true;
+            if (name.contains("nvidia"))
+                m_bNvidia = true;
 
-        Debug::log(LOG, "Primary DRM driver information: {} v{}.{}.{} from {} description {}", name, DRMV->version_major, DRMV->version_minor, DRMV->version_patchlevel,
-                   std::string{DRMV->date, DRMV->date_len}, std::string{DRMV->desc, DRMV->desc_len});
+            Debug::log(LOG, "Primary DRM driver information: {} v{}.{}.{} from {} description {}", name, DRMV->version_major, DRMV->version_minor, DRMV->version_patchlevel,
+                       std::string{DRMV->date, DRMV->date_len}, std::string{DRMV->desc, DRMV->desc_len});
+        } else {
+            Debug::log(LOG, "No primary DRM driver information found");
+        }
 
         drmFreeVersion(DRMV);
     }