From 021e0dde7d76854758daa2212e358deddde29925 Mon Sep 17 00:00:00 2001
From: Brad Smith <brad@comstyle.com>
Date: Mon, 30 Dec 2024 04:38:09 -0500
Subject: [PATCH] ArmCPUDetect: Add OpenBSD support for elf_aux_info

---
 Source/CMakeLists.txt               |  5 +++++
 Source/Core/Common/ArmCPUDetect.cpp | 27 ++++++++++++++++++++-------
 2 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/Source/CMakeLists.txt b/Source/CMakeLists.txt
index e589e4298366..ace938da5173 100644
--- a/Source/CMakeLists.txt
+++ b/Source/CMakeLists.txt
@@ -68,6 +68,11 @@ endif()
 add_definitions(-D__STDC_LIMIT_MACROS)
 add_definitions(-D__STDC_CONSTANT_MACROS)
 
+check_symbol_exists(elf_aux_info sys/auxv.h HAVE_ELF_AUX_INFO)
+if(HAVE_ELF_AUX_INFO)
+    add_definitions(-DHAVE_ELF_AUX_INFO)
+endif()
+
 add_subdirectory(Core)
 if (ANDROID)
   add_subdirectory(Android/jni)
diff --git a/Source/Core/Common/ArmCPUDetect.cpp b/Source/Core/Common/ArmCPUDetect.cpp
index 90cc0f7b44a4..b3213321e596 100644
--- a/Source/Core/Common/ArmCPUDetect.cpp
+++ b/Source/Core/Common/ArmCPUDetect.cpp
@@ -18,13 +18,16 @@
 #elif defined(__linux__)
 #include <asm/hwcap.h>
 #include <sys/auxv.h>
-#elif defined(__FreeBSD__)
+#elif defined(HAVE_ELF_AUX_INFO)
 #include <sys/auxv.h>
 #elif defined(__OpenBSD__)
 #include <machine/armreg.h>
 #include <machine/cpu.h>
-#include <sys/sysctl.h>
+#endif
+
+#ifdef __OpenBSD__
 #include <sys/types.h>
+#include <sys/sysctl.h>
 #endif
 
 #include <fmt/format.h>
@@ -142,13 +145,13 @@ static bool Read_MIDR_EL1_Sysfs(u64* value)
 
 #endif
 
-#if defined(__linux__) || defined(__FreeBSD__)
+#if defined(__linux__) || defined(HAVE_ELF_AUX_INFO)
 
 static u32 ReadHwCap(u32 type)
 {
 #if defined(__linux__)
   return getauxval(type);
-#elif defined(__FreeBSD__)
+#elif defined(HAVE_ELF_AUX_INFO)
   u_long hwcap = 0;
   elf_aux_info(type, &hwcap, sizeof(hwcap));
   return hwcap;
@@ -189,7 +192,7 @@ static bool Read_MIDR_EL1(u64* value)
 
 #endif
 
-#if defined(_WIN32) || defined(__linux__) || defined(__FreeBSD__)
+#if defined(_WIN32) || defined(__linux__) || defined(HAVE_ELF_AUX_INFO)
 
 static std::string MIDRToString(u64 midr)
 {
@@ -254,11 +257,21 @@ void CPUInfo::Detect()
   {
     cpu_id = MIDRToString(reg);
   }
-#elif defined(__linux__) || defined(__FreeBSD__)
-  // Linux, Android, and FreeBSD
+#elif defined(__linux__) || defined(HAVE_ELF_AUX_INFO)
+  // Linux, Android, FreeBSD and OpenBSD with elf_aux_info
 
 #if defined(__FreeBSD__)
   SysctlByName(&model_name, "hw.model");
+#elif defined(__OpenBSD__)
+  int mib[2];
+  size_t len;
+  char hwmodel[256];
+
+  mib[0] = CTL_HW;
+  mib[1] = HW_MODEL;
+  len = std::size(hwmodel);
+  if (sysctl(mib, 2, &hwmodel, &len, nullptr, 0) != -1)
+    model_name = std::string(hwmodel, len - 1);
 #elif defined(__linux__)
   if (!ReadDeviceTree(&model_name, "model"))
   {