From 7733912ae289440497e0cbdcfca0a373880d025a Mon Sep 17 00:00:00 2001
From: icex2 <djh.icex2@gmail.com>
Date: Fri, 21 Aug 2020 17:53:32 +0200
Subject: [PATCH] util: Add OS module to get version information of Windows

Data we always need when things go wrong, log it on boot.
---
 src/main/util/Module.mk |   1 +
 src/main/util/os.c      | 130 ++++++++++++++++++++++++++++++++++++++++
 src/main/util/os.h      |  25 ++++++++
 3 files changed, 156 insertions(+)
 create mode 100644 src/main/util/os.c
 create mode 100644 src/main/util/os.h

diff --git a/src/main/util/Module.mk b/src/main/util/Module.mk
index f6b42ff..74c508a 100644
--- a/src/main/util/Module.mk
+++ b/src/main/util/Module.mk
@@ -13,6 +13,7 @@ src_util        := \
     mem.c \
     msg-thread.c \
     net.c \
+    os.c \
     signal.c \
     str.c \
     thread.c \
diff --git a/src/main/util/os.c b/src/main/util/os.c
new file mode 100644
index 0000000..4609881
--- /dev/null
+++ b/src/main/util/os.c
@@ -0,0 +1,130 @@
+#define LOG_MODULE "util-os"
+
+#include <windows.h>
+
+#include <versionhelpers.h>
+
+#include <stdbool.h>
+
+#include "util/log.h"
+#include "util/os.h"
+#include "util/str.h"
+
+#define STATUS_SUCCESS (0x00000000)
+
+typedef LONG NTSTATUS, *PNTSTATUS;
+typedef NTSTATUS (WINAPI* RtlGetVersion_t)(PRTL_OSVERSIONINFOW);
+
+static const char* human_readable_version(DWORD major, DWORD minor)
+{
+    if (IsWindowsServer()) {
+        if (major == 5 && minor == 2) {
+            return "Windows Server 2003 (R2)";
+        } else if (major == 6 && minor == 0) {
+            return "Windows Server 2008";
+        } else if (major == 6 && minor == 1) {
+            return "Windows Server 2008 R2";
+        } else if (major == 6 && minor == 2) {
+            return "Windows Server 2012";
+        } else if (major == 6 && minor == 3) {
+            return "Windows Server 2012 R2";
+        } else if (major == 10 && minor == 0) {
+            return "Windows Server 2016/2019";
+        } else {
+            return "Unknown server version";
+        }
+    } else {
+        if (major == 5 && minor == 0) {
+            return "Windows 2000";
+        } else if (major == 5 && minor == 1) {
+            return "Windows XP";
+        } else if (major == 5 && minor == 2 ) {
+            return "Windows XP 64-bit";
+        } else if (major == 6 && minor == 0) {
+            return "Windows Vista";
+        } else if (major == 6 && minor == 1) {
+            return "Windows 7";
+        } else if (major == 6 && minor == 2) {
+            return "Windows 8";
+        } else if (major == 6 && minor == 3) {
+            return "Windows 8.1";
+        } else if (major == 10 && minor == 0) {
+            return "Windows 10";
+        } else {
+            return "Unknown client version";
+        }
+    }
+}
+
+static bool os_get_real_win_version(PRTL_OSVERSIONINFOW version)
+{
+    HMODULE module;
+    RtlGetVersion_t rtl_get_version;
+
+    module = GetModuleHandleA("ntdll.dll");
+
+    if (!module) {
+        return false;
+    }
+
+    rtl_get_version = (RtlGetVersion_t) GetProcAddress(module, "RtlGetVersion");
+
+    if (!rtl_get_version) {
+        return false;
+    }
+
+    return rtl_get_version(version) == STATUS_SUCCESS;
+}
+
+bool os_version_get(struct os_version* version)
+{
+    log_assert(version);
+
+    RTL_OSVERSIONINFOW rovi;
+    char* version_str;
+    const char* readable_version;
+
+    memset(&rovi, 0, sizeof(RTL_OSVERSIONINFOW));
+    rovi.dwOSVersionInfoSize = sizeof(rovi);
+
+    version_str = NULL;
+
+    if (!os_get_real_win_version(&rovi)) {
+        return false;
+    }
+
+    // Contains additional version info, e.g. "Service Pack 3" for XP
+    wstr_narrow(rovi.szCSDVersion, &version_str);
+
+    readable_version = human_readable_version(rovi.dwMajorVersion, rovi.dwMinorVersion);
+
+    strcpy(version->name, readable_version);
+    version->major = rovi.dwMajorVersion;
+    version->minor = rovi.dwMinorVersion;
+    version->build = rovi.dwBuildNumber;
+    version->platform_id = rovi.dwPlatformId;
+    strcpy(version->extension, version_str);
+
+    if (version_str) {
+        free(version_str);
+    }
+
+    return true;
+}
+
+void os_version_log()
+{
+    struct os_version version;
+
+    if (!os_version_get(&version)) {
+        log_warning("Could not detect OS version");
+    } else {
+        log_info("OS version: %s - %d.%d.%d.%d - %s",
+            version.name,
+            version.major,
+            version.minor,
+            version.build,
+            version.platform_id,
+            version.extension);
+    }
+}
\ No newline at end of file
diff --git a/src/main/util/os.h b/src/main/util/os.h
new file mode 100644
index 0000000..8df0686
--- /dev/null
+++ b/src/main/util/os.h
@@ -0,0 +1,25 @@
+#pragma once
+
+#include <stdint.h>
+
+struct os_version {
+    char name[128];
+    uint32_t major;
+    uint32_t minor;
+    uint32_t build;
+    uint32_t platform_id;
+    char extension[256];
+};
+
+/**
+ * Get the (real) version information of the Windows OS.
+ * 
+ * @param verison Pointer to version structure. This will be filled in.
+ * @return true on success, false on failure.
+ */
+bool os_version_get(struct os_version* version);
+
+/**
+ * Log the version information of the current Windows OS.
+ */
+void os_version_log();
\ No newline at end of file