From c28ced9dcb3b55cb8a4b8432752a52fe6398f135 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E6=9D=8E=E9=80=9A=E6=B4=B2?= <zhangsongcui3371@sina.com>
Date: Tue, 8 Aug 2023 20:23:26 +0800
Subject: [PATCH] NativeResolution (Linux): add support

---
 CMakeLists.txt                                |  3 +-
 .../nativeresolution/nativeresolution_linux.c | 60 +++++++++++++++++++
 src/util/edidHelper.c                         |  8 +++
 src/util/edidHelper.h                         | 10 ++++
 4 files changed, 80 insertions(+), 1 deletion(-)
 create mode 100644 src/detection/nativeresolution/nativeresolution_linux.c
 create mode 100644 src/util/edidHelper.c
 create mode 100644 src/util/edidHelper.h

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1792122dc..4dc60b91e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -356,6 +356,7 @@ set(LIBFASTFETCH_SRC
     src/modules/wifi/wifi.c
     src/modules/wm/wm.c
     src/modules/wmtheme/wmtheme.c
+    src/util/edidHelper.c
     src/util/FFlist.c
     src/util/FFstrbuf.c
     src/util/platform/FFPlatform.c
@@ -394,7 +395,7 @@ if(LINUX)
         src/detection/gamepad/gamepad_linux.c
         src/detection/media/media_linux.c
         src/detection/memory/memory_linux.c
-        src/detection/nativeresolution/nativeresolution_nosupport.c
+        src/detection/nativeresolution/nativeresolution_linux.c
         src/detection/opengl/opengl_linux.c
         src/detection/os/os_linux.c
         src/detection/packages/packages_linux.c
diff --git a/src/detection/nativeresolution/nativeresolution_linux.c b/src/detection/nativeresolution/nativeresolution_linux.c
new file mode 100644
index 000000000..bb7e5a5e1
--- /dev/null
+++ b/src/detection/nativeresolution/nativeresolution_linux.c
@@ -0,0 +1,60 @@
+#include "nativeresolution.h"
+
+#include "common/io/io.h"
+#include "util/edidHelper.h"
+#include "util/stringUtils.h"
+
+#include <dirent.h>
+
+const char* ffDetectNativeResolution(FFlist* results)
+{
+    const char* drmDirPath = "/sys/class/drm/";
+
+    DIR* dirp = opendir(drmDirPath);
+    if(dirp == NULL)
+        return "opendir(drmDirPath) == NULL";
+
+    FF_STRBUF_AUTO_DESTROY drmDir = ffStrbufCreateA(64);
+    ffStrbufAppendS(&drmDir, drmDirPath);
+
+    uint32_t drmDirLength = drmDir.length;
+
+    struct dirent* entry;
+    while((entry = readdir(dirp)) != NULL)
+    {
+        if(ffStrEquals(entry->d_name, ".") || ffStrEquals(entry->d_name, ".."))
+            continue;
+
+        ffStrbufAppendS(&drmDir, entry->d_name);
+        ffStrbufAppendS(&drmDir, "/edid");
+
+        uint8_t edidData[128];
+        if(ffReadFileData(drmDir.chars, sizeof(edidData), edidData) != sizeof(edidData))
+        {
+            ffStrbufSubstrBefore(&drmDir, drmDirLength);
+            continue;
+        }
+
+        uint32_t width, height;
+        ffEdidGetNativeResolution(edidData, &width, &height);
+        if (width != 0 && height != 0)
+        {
+            const char* plainName = entry->d_name;
+            if (ffStrStartsWith(plainName, "card"))
+            {
+                const char* tmp = strchr(plainName + strlen("card"), '-');
+                if (tmp) plainName = tmp + 1;
+            }
+
+            FFNativeResolutionResult* display = (FFNativeResolutionResult*) ffListAdd(results);
+            display->width = width;
+            display->height = height;
+            ffStrbufInitS(&display->name, plainName);
+        }
+
+        ffStrbufSubstrBefore(&drmDir, drmDirLength);
+    }
+
+    closedir(dirp);
+    return NULL;
+}
diff --git a/src/util/edidHelper.c b/src/util/edidHelper.c
new file mode 100644
index 000000000..fa765d55f
--- /dev/null
+++ b/src/util/edidHelper.c
@@ -0,0 +1,8 @@
+#include "edidHelper.h"
+
+void ffEdidGetNativeResolution(uint8_t edid[128], uint32_t* width, uint32_t* height)
+{
+    const int dtd = 54;
+    *width = ((edid[dtd + 4] >> 4) << 8) | edid[dtd + 2];
+    *height = ((edid[dtd + 7] >> 4) << 8) | edid[dtd + 5];
+}
diff --git a/src/util/edidHelper.h b/src/util/edidHelper.h
new file mode 100644
index 000000000..8a9540860
--- /dev/null
+++ b/src/util/edidHelper.h
@@ -0,0 +1,10 @@
+#pragma once
+
+#ifndef FF_INCLUDED_EDID_HELPER_H
+#define FF_INCLUDED_EDID_HELPER_H
+
+#include <stdint.h>
+
+void ffEdidGetNativeResolution(uint8_t edid[128], uint32_t* width, uint32_t* height);
+
+#endif