Add new configuration mechanism for CoreCLR.

Author: adityamandaleeka

src/dlls/mscoree/unixinterface.cpp

@@ -6,14 +6,15 @@
 //*****************************************************************************
 // unixinterface.cpp
 //
-// Implementation for the interface exposed by the libcoreclr.so on Unix
+// Implementation for the interface exposed by libcoreclr.so
 //
 
 //*****************************************************************************
 
 #include "stdafx.h"
 #include <utilcode.h>
 #include <corhost.h>
+#include <configuration.h>
 
 typedef int (STDMETHODCALLTYPE *HostMain)(
     const int argc,
@@ -86,76 +87,47 @@ static LPCWSTR* StringArrayToUnicode(int argc, LPCSTR* argv)
     return argvW;
 }
 
-static void ExtractStartupFlagsAndConvertToUnicode(
+static void InitializeStartupFlags(STARTUP_FLAGS* startupFlagsRef)
+{
+    STARTUP_FLAGS startupFlags = static_cast<STARTUP_FLAGS>(
+            STARTUP_FLAGS::STARTUP_LOADER_OPTIMIZATION_SINGLE_DOMAIN |
+            STARTUP_FLAGS::STARTUP_SINGLE_APPDOMAIN);
+
+    if (Configuration::GetKnobBooleanValue(W("System.GC.Concurrent"), CLRConfig::UNSUPPORTED_gcConcurrent))
+    {
+        startupFlags = static_cast<STARTUP_FLAGS>(startupFlags | STARTUP_CONCURRENT_GC);
+    }
+    if (Configuration::GetKnobBooleanValue(W("System.GC.Server"), CLRConfig::UNSUPPORTED_gcServer))
+    {
+        startupFlags = static_cast<STARTUP_FLAGS>(startupFlags | STARTUP_SERVER_GC);
+    }
+    if (Configuration::GetKnobBooleanValue(W("System.GC.RetainVM"), CLRConfig::UNSUPPORTED_GCRetainVM))
+    {
+        startupFlags = static_cast<STARTUP_FLAGS>(startupFlags | STARTUP_HOARD_GC_VM);
+    }
+
+    *startupFlagsRef = startupFlags;
+}
+
+static void ConvertConfigPropertiesToUnicode(
     const char** propertyKeys,
     const char** propertyValues,
-    int* propertyCountRef,
-    STARTUP_FLAGS* startupFlagsRef,
+    int propertyCount,
     LPCWSTR** propertyKeysWRef,
     LPCWSTR** propertyValuesWRef)
 {
-    int propertyCount = *propertyCountRef;
-
     LPCWSTR* propertyKeysW = new (nothrow) LPCWSTR[propertyCount];
     ASSERTE_ALL_BUILDS(propertyKeysW != nullptr);
 
     LPCWSTR* propertyValuesW = new (nothrow) LPCWSTR[propertyCount];
     ASSERTE_ALL_BUILDS(propertyValuesW != nullptr);
 
-    // Extract the startup flags from the properties, and convert the remaining properties into unicode
-    STARTUP_FLAGS startupFlags =
-        static_cast<STARTUP_FLAGS>(
-            STARTUP_FLAGS::STARTUP_LOADER_OPTIMIZATION_SINGLE_DOMAIN |
-            STARTUP_FLAGS::STARTUP_SINGLE_APPDOMAIN |
-            STARTUP_FLAGS::STARTUP_CONCURRENT_GC);
-    int propertyCountW = 0;
     for (int propertyIndex = 0; propertyIndex < propertyCount; ++propertyIndex)
     {
-        auto SetFlagValue = [&](STARTUP_FLAGS flag)
-        {
-            if (strcmp(propertyValues[propertyIndex], "0") == 0)
-            {
-                startupFlags = static_cast<STARTUP_FLAGS>(startupFlags & ~flag);
-            }
-            else if (strcmp(propertyValues[propertyIndex], "1") == 0)
-            {
-                startupFlags = static_cast<STARTUP_FLAGS>(startupFlags | flag);
-            }
-        };
-
-        if (strcmp(propertyKeys[propertyIndex], "CONCURRENT_GC") == 0)
-        {
-            SetFlagValue(STARTUP_CONCURRENT_GC);
-        }
-        else if (strcmp(propertyKeys[propertyIndex], "SERVER_GC") == 0)
-        {
-            SetFlagValue(STARTUP_SERVER_GC);
-        }
-        else if (strcmp(propertyKeys[propertyIndex], "HOARD_GC_VM") == 0)
-        {
-            SetFlagValue(STARTUP_HOARD_GC_VM);
-        }
-        else if (strcmp(propertyKeys[propertyIndex], "TRIM_GC_COMMIT") == 0)
-        {
-            SetFlagValue(STARTUP_TRIM_GC_COMMIT);
-        }
-        else
-        {
-            // This is not a CoreCLR startup flag, convert it to unicode and preserve it for returning
-            propertyKeysW[propertyCountW] = StringToUnicode(propertyKeys[propertyIndex]);
-            propertyValuesW[propertyCountW] = StringToUnicode(propertyValues[propertyIndex]);
-            ++propertyCountW;
-        }
-    }
-
-    for (int propertyIndex = propertyCountW; propertyIndex < propertyCount; ++propertyIndex)
-    {
-        propertyKeysW[propertyIndex] = nullptr;
-        propertyValuesW[propertyIndex] = nullptr;
+        propertyKeysW[propertyIndex] = StringToUnicode(propertyKeys[propertyIndex]);
+        propertyValuesW[propertyIndex] = StringToUnicode(propertyValues[propertyIndex]);
     }
 
-    *propertyCountRef = propertyCountW;
-    *startupFlagsRef = startupFlags;
     *propertyKeysWRef = propertyKeysW;
     *propertyValuesWRef = propertyValuesW;
 }
@@ -205,22 +177,20 @@ int coreclr_initialize(
 
     ConstWStringHolder appDomainFriendlyNameW = StringToUnicode(appDomainFriendlyName);
 
-    STARTUP_FLAGS startupFlags;
-    LPCWSTR* propertyKeysWTemp;
-    LPCWSTR* propertyValuesWTemp;
-    ExtractStartupFlagsAndConvertToUnicode(
+    LPCWSTR* propertyKeysW;
+    LPCWSTR* propertyValuesW;
+    ConvertConfigPropertiesToUnicode(
         propertyKeys,
         propertyValues,
-        &propertyCount,
-        &startupFlags,
-        &propertyKeysWTemp,
-        &propertyValuesWTemp);
-    
-    ConstWStringArrayHolder propertyKeysW;
-    propertyKeysW.Set(propertyKeysWTemp, propertyCount);
-    
-    ConstWStringArrayHolder propertyValuesW;
-    propertyValuesW.Set(propertyValuesWTemp, propertyCount);
+        propertyCount,
+        &propertyKeysW,
+        &propertyValuesW);
+
+    // This will take ownership of propertyKeysWTemp and propertyValuesWTemp
+    Configuration::InitializeConfigurationKnobs(propertyCount, propertyKeysW, propertyValuesW);
+
+    STARTUP_FLAGS startupFlags;
+    InitializeStartupFlags(&startupFlags);
 
     hr = host->SetStartupFlags(startupFlags);
     IfFailRet(hr);

src/inc/clrconfig.h

@@ -171,7 +171,10 @@ class CLRConfig
 
     // Look up a DWORD config value.
     static DWORD GetConfigValue(const ConfigDWORDInfo & info);
-    
+
+    // Look up a DWORD config value.
+    static DWORD GetConfigValue(const ConfigDWORDInfo & info, bool acceptExplicitDefaultFromRegutil, /* [Out] */ bool *isDefault);
+
     // Look up a string config value.
     // You own the string that's returned.
     static LPWSTR GetConfigValue(const ConfigStringInfo & info);

src/inc/clrconfigvalues.h

@@ -309,6 +309,7 @@ CONFIG_DWORD_INFO(INTERNAL_FastGCCheckStack, W("FastGCCheckStack"), 0, "")
 CONFIG_DWORD_INFO_DIRECT_ACCESS(INTERNAL_FastGCStress, W("FastGCStress"), "reduce the number of GCs done by enabling GCStress")
 RETAIL_CONFIG_DWORD_INFO_DIRECT_ACCESS(UNSUPPORTED_GCBreakOnOOM, W("GCBreakOnOOM"), "Does a DebugBreak at the soonest time we detect an OOM")
 RETAIL_CONFIG_DWORD_INFO(UNSUPPORTED_gcConcurrent, W("gcConcurrent"), (DWORD)-1, "Enables/Disables concurrent GC")
+
 #ifdef FEATURE_CONSERVATIVE_GC
 RETAIL_CONFIG_DWORD_INFO(UNSUPPORTED_gcConservative, W("gcConservative"), 0, "Enables/Disables conservative GC")
 #endif
@@ -335,7 +336,7 @@ RETAIL_CONFIG_DWORD_INFO(UNSUPPORTED_GCCompactRatio, W("GCCompactRatio"), 0, "Sp
 RETAIL_CONFIG_DWORD_INFO_DIRECT_ACCESS(EXTERNAL_GCPollType, W("GCPollType"), "")
 RETAIL_CONFIG_STRING_INFO_EX(EXTERNAL_NewGCCalc, W("NewGCCalc"), "", CLRConfig::REGUTIL_default)
 RETAIL_CONFIG_DWORD_INFO_DIRECT_ACCESS(UNSUPPORTED_GCprnLvl, W("GCprnLvl"), "Specifies the maximum level of GC logging")
-RETAIL_CONFIG_DWORD_INFO_DIRECT_ACCESS(UNSUPPORTED_GCRetainVM, W("GCRetainVM"), "When set we put the segments that should be deleted on a standby list (instead of releasing them back to the OS) which will be considered to satisfy new segment requests (note that the same thing can be specified via API which is the supported way)")
+RETAIL_CONFIG_DWORD_INFO(UNSUPPORTED_GCRetainVM, W("GCRetainVM"), 0, "When set we put the segments that should be deleted on a standby list (instead of releasing them back to the OS) which will be considered to satisfy new segment requests (note that the same thing can be specified via API which is the supported way)")
 RETAIL_CONFIG_DWORD_INFO_DIRECT_ACCESS(UNSUPPORTED_GCSegmentSize, W("GCSegmentSize"), "Specifies the managed heap segment size")
 RETAIL_CONFIG_DWORD_INFO_DIRECT_ACCESS(UNSUPPORTED_GCLOHCompact, W("GCLOHCompact"), "Specifies the LOH compaction mode")
 RETAIL_CONFIG_DWORD_INFO(EXTERNAL_gcAllowVeryLargeObjects, W("gcAllowVeryLargeObjects"), 0, "allow allocation of 2GB+ objects on GC heap")

src/inc/configuration.h

@@ -0,0 +1,57 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+// 
+// --------------------------------------------------------------------------------------------------
+// configuration.h
+// 
+// 
+// Access and update configuration values, falling back on legacy CLRConfig methods where necessary.
+// 
+// --------------------------------------------------------------------------------------------------
+
+#include "clrconfig.h"
+
+#ifndef __configuration_h__
+#define __configuration_h__
+
+class Configuration
+{
+public:
+    static void InitializeConfigurationKnobs(int numberOfConfigs, LPCWSTR *configNames, LPCWSTR *configValues);
+
+    // Returns (in priority order):
+    //    - The value of the ConfigDWORDInfo if it's set
+    //    - The value of the ConfigurationKnob (searched by name) if it's set (performs a wcstoul).
+    //    - The default set in the ConfigDWORDInfo
+    static DWORD GetKnobDWORDValue(LPCWSTR name, const CLRConfig::ConfigDWORDInfo& dwordInfo);
+
+    // Returns (in priority order):
+    //    - The value of the ConfigurationKnob (searched by name) if it's set (performs a wcstoul)
+    //    - The default value passed in
+    static DWORD GetKnobDWORDValue(LPCWSTR name, DWORD defaultValue);
+
+    // Returns (in priority order):
+    //    - The value of the ConfigStringInfo if it's set
+    //    - The value of the ConfigurationKnob (searched by name) if it's set
+    //    - nullptr
+    static LPCWSTR GetKnobStringValue(LPCWSTR name, const CLRConfig::ConfigStringInfo& stringInfo);
+
+    // Returns (in priority order):
+    //    - The value of the ConfigurationKnob (searched by name) if it's set
+    //    - nullptr
+    static LPCWSTR GetKnobStringValue(LPCWSTR name);
+
+    // Returns (in priority order):
+    //    - The value of the ConfigDWORDInfo if it's set (1 is true, anything else is false)
+    //    - The value of the ConfigurationKnob (searched by name) if it's set (performs a wcscmp with "true").
+    //    - The default set in the ConfigDWORDInfo (1 is true, anything else is false)
+    static bool GetKnobBooleanValue(LPCWSTR name, const CLRConfig::ConfigDWORDInfo& dwordInfo);
+
+    // Returns (in priority order):
+    //    - The value of the ConfigurationKnob (searched by name) if it's set (performs a wcscmp with "true").
+    //    - The default value passed in
+    static bool GetKnobBooleanValue(LPCWSTR name, bool defaultValue);
+};
+
+#endif // __configuration_h__

src/utilcode/CMakeLists.txt

@@ -16,6 +16,7 @@ set(UTILCODE_COMMON_SOURCES
   makepath.cpp
   splitpath.cpp
   clrconfig.cpp
+  configuration.cpp
   collections.cpp
   posterror.cpp
   fstream.cpp

src/utilcode/UtilCode.vcproj

@@ -375,6 +375,9 @@
 		<File
 			RelativePath=".\CLRConfig.cpp"
 			>
+		<File
+			RelativePath=".\configuration.cpp"
+			>
 		</File>
 		<File
 			RelativePath=".\clrhost.cpp"

src/utilcode/UtilCode.vcxproj

@@ -382,6 +382,7 @@
     <ClCompile Include="check.cpp" />
     <ClCompile Include="circularlog.cpp" />
     <ClCompile Include="CLRConfig.cpp" />
+    <ClCompile Include="configuration.cpp" />
     <ClCompile Include="clrhost.cpp" />
     <ClCompile Include="COMEx.cpp" />
     <ClCompile Include="corimage.cpp" />