Support loading ICU data from managed Interop (#49406)

In iOS we support loading a custom dat file when working with ICU.  The way this worked originally was the mono runtime exported a function that native code would call into (similar to wasm).  After thinking about it a bit, it makes more sense to load this the same way we do on desktop, but with the ability to provide the path to an ICU dat file via an AppContext key `ICU_DAT_FILE_PATH`.  This can be provided before Xamarin iOS calls `monovm_initialize` and they won't have to worry about calling some special function.

Author: steveisok

src/libraries/Common/src/Interop/Interop.ICU.iOS.cs

@@ -0,0 +1,14 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System;
+using System.Runtime.InteropServices;
+
+internal static partial class Interop
+{
+    internal static partial class Globalization
+    {
+        [DllImport(Libraries.GlobalizationNative, EntryPoint = "GlobalizationNative_LoadICUData")]
+        internal static extern int LoadICUData(string path);
+    }
+}

src/libraries/Native/Unix/System.Globalization.Native/entrypoints.c

@@ -50,6 +50,9 @@ static const Entry s_globalizationNative[] =
     DllImportEntry(GlobalizationNative_IsPredefinedLocale)
     DllImportEntry(GlobalizationNative_LastIndexOf)
     DllImportEntry(GlobalizationNative_LoadICU)
+#if defined(STATIC_ICU)
+    DllImportEntry(GlobalizationNative_LoadICUData)
+#endif
     DllImportEntry(GlobalizationNative_NormalizeString)
     DllImportEntry(GlobalizationNative_StartsWith)
     DllImportEntry(GlobalizationNative_ToAscii)

src/libraries/Native/Unix/System.Globalization.Native/pal_icushim.h

@@ -11,7 +11,7 @@ PALEXPORT int32_t GlobalizationNative_GetICUVersion(void);
 
 #if defined(STATIC_ICU)
 
-PALEXPORT int32_t GlobalizationNative_LoadICUData(char* path);
+PALEXPORT int32_t GlobalizationNative_LoadICUData(const char* path);
 
 PALEXPORT const char* GlobalizationNative_GetICUDTName(const char* culture);
 

src/libraries/Native/Unix/System.Globalization.Native/pal_icushim_static.c

@@ -22,10 +22,19 @@
 static int32_t isLoaded = 0;
 static int32_t isDataSet = 0;
 
+static void log_shim_error(const char* format, ...)
+{
+    va_list args;
+
+    va_start(args, format);
+    vfprintf(stderr, format, args);
+    va_end(args);
+}
+
 static void log_icu_error(const char* name, UErrorCode status)
 {
     const char * statusText = u_errorName(status);
-    fprintf(stderr, "ICU call %s failed with error #%d '%s'.\n", name, status, statusText);
+    log_shim_error("ICU call %s failed with error #%d '%s'.\n", name, status, statusText);
 }
 
 static void U_CALLCONV icu_trace_data(const void* context, int32_t fnNumber, int32_t level, const char* fmt, va_list args)
@@ -89,45 +98,60 @@ static int32_t load_icu_data(void* pData)
     }
 }
 
-int32_t GlobalizationNative_LoadICUData(char* path)
+int32_t GlobalizationNative_LoadICUData(const char* path)
 {
     int32_t ret = -1;
     char* icu_data;
 
-    FILE *fp = fopen (path, "rb");
+    FILE *fp = fopen(path, "rb");
     if (fp == NULL) {
-        fprintf (stderr,  "Unable to load ICU dat file '%s'.", path);
+        log_shim_error("Unable to load ICU dat file '%s'.", path);
         return ret;
     }
 
-    if (fseek (fp, 0L, SEEK_END) != 0) {
-        fprintf (stderr, "Unable to determine size of the dat file");
+    if (fseek(fp, 0L, SEEK_END) != 0) {
+        fclose(fp);
+        log_shim_error("Unable to determine size of the dat file");
         return ret;
     }
 
-    long bufsize = ftell (fp);
+    long bufsize = ftell(fp);
 
     if (bufsize == -1) {
-        fprintf (stderr, "Unable to determine size of the ICU dat file.");
+        fclose(fp);
+        log_shim_error("Unable to determine size of the ICU dat file.");
         return ret;
     }
 
-    icu_data = malloc (sizeof (char) * (bufsize + 1));
+    icu_data = malloc(sizeof(char) * (bufsize + 1));
+
+    if (icu_data == NULL) {
+        fclose(fp);
+        log_shim_error("Unable to allocate enough to read the ICU dat file");
+        return ret;
+    }
 
-    if (fseek (fp, 0L, SEEK_SET) != 0) {
-        fprintf (stderr, "Unable to seek ICU dat file.");
+    if (fseek(fp, 0L, SEEK_SET) != 0) {
+        fclose(fp);
+        log_shim_error("Unable to seek ICU dat file.");
         return ret;
     }
 
-    fread (icu_data, sizeof (char), bufsize, fp);
-    if (ferror ( fp ) != 0 ) {
-        fprintf (stderr, "Unable to read ICU dat file");
+    fread(icu_data, sizeof(char), bufsize, fp);
+    if (ferror( fp ) != 0 ) {
+        fclose(fp);
+        log_shim_error("Unable to read ICU dat file");
         return ret;
     }
 
-    fclose (fp);
+    fclose(fp);
+
+    if (load_icu_data(icu_data) == 0) {
+        log_shim_error("ICU BAD EXIT %d.", ret);
+        return ret;
+    }
 
-    return load_icu_data (icu_data);
+    return GlobalizationNative_LoadICU();
 }
 
 const char* GlobalizationNative_GetICUDTName(const char* culture)

src/libraries/System.Private.CoreLib/src/System.Private.CoreLib.Shared.projitems

@@ -11,6 +11,7 @@
   <PropertyGroup>
     <Nullable>enable</Nullable>
     <IsOSXLike Condition="'$(TargetsOSX)' == 'true' or '$(TargetsMacCatalyst)' == 'true' or '$(TargetsiOS)' == 'true' or '$(TargetstvOS)' == 'true'">true</IsOSXLike>
+    <IsiOSLike Condition="'$(TargetsMacCatalyst)' == 'true' or '$(TargetsiOS)' == 'true' or '$(TargetstvOS)' == 'true'">true</IsiOSLike>
     <SupportsArmIntrinsics Condition="'$(Platform)' == 'arm64'">true</SupportsArmIntrinsics>
     <SupportsX86Intrinsics Condition="'$(Platform)' == 'x64' or ('$(Platform)' == 'x86' and '$(TargetsUnix)' != 'true')">true</SupportsX86Intrinsics>
     <ILLinkSharedDirectory>$(MSBuildThisFileDirectory)ILLink\</ILLinkSharedDirectory>
@@ -1082,6 +1083,9 @@
     <Compile Include="$(CommonPath)Interop\Interop.ICU.cs">
       <Link>Common\Interop\Interop.ICU.cs</Link>
     </Compile>
+    <Compile Include="$(CommonPath)Interop\Interop.ICU.iOS.cs" Condition="'$(IsiOSLike)' == 'true'">
+      <Link>Common\Interop\Interop.ICU.iOS.cs</Link>
+    </Compile>
     <Compile Include="$(CommonPath)Interop\Interop.Idna.cs">
       <Link>Common\Interop\Interop.Idna.cs</Link>
     </Compile>
@@ -1831,11 +1835,13 @@
     <Compile Include="$(MSBuildThisFileDirectory)System\Environment.NoRegistry.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Environment.UnixOrBrowser.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Environment.OSVersion.OSX.cs" Condition="'$(IsOSXLike)' == 'true'" />
-    <Compile Include="$(MSBuildThisFileDirectory)System\Environment.GetFolderPathCore.Unix.cs" Condition="'$(TargetsMacCatalyst)' != 'true' and '$(TargetsiOS)' != 'true' and '$(TargetstvOS)' != 'true'" />
+    <Compile Include="$(MSBuildThisFileDirectory)System\Environment.GetFolderPathCore.Unix.cs" Condition="'$(IsiOSLike)' != 'true'" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\CalendarData.Unix.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\CultureData.Unix.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\CultureInfo.Unix.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\GlobalizationMode.Unix.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\GlobalizationMode.LoadICU.Unix.cs" Condition="'$(IsiOSLike)' != 'true'" />
+    <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\GlobalizationMode.LoadICU.iOS.cs" Condition="'$(IsiOSLike)' == 'true'" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\HijriCalendar.Unix.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Guid.Unix.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\IO\FileStreamHelpers.Unix.cs" />

src/libraries/System.Private.CoreLib/src/System/Globalization/GlobalizationMode.LoadICU.Unix.cs

@@ -0,0 +1,10 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace System.Globalization
+{
+    internal static partial class GlobalizationMode
+    {
+        private static int LoadICU() => Interop.Globalization.LoadICU();
+    }
+}

src/libraries/System.Private.CoreLib/src/System/Globalization/GlobalizationMode.LoadICU.iOS.cs

@@ -0,0 +1,14 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace System.Globalization
+{
+    internal static partial class GlobalizationMode
+    {
+        private static int LoadICU()
+        {
+            object? datPath = AppContext.GetData("ICU_DAT_FILE_PATH");
+            return (datPath != null) ? Interop.Globalization.LoadICUData(datPath!.ToString()!) : Interop.Globalization.LoadICU();
+        }
+    }
+}

src/libraries/System.Private.CoreLib/src/System/Globalization/GlobalizationMode.Unix.cs

@@ -22,7 +22,7 @@ private static bool GetGlobalizationInvariantMode()
                 }
                 else
                 {
-                    int loaded = Interop.Globalization.LoadICU();
+                    int loaded = LoadICU();
                     if (loaded == 0 && !OperatingSystem.IsBrowser())
                     {
                         // This can't go into resources, because a resource lookup requires globalization, which requires ICU

src/mono/mono/mini/CMakeLists.txt

@@ -50,6 +50,7 @@ if(HAVE_SYS_ICU)
   if(STATIC_ICU)
     set(pal_icushim_sources_base
         pal_icushim_static.c)
+    add_definitions(-DSTATIC_ICU=1)
   else()
     set(pal_icushim_sources_base
         pal_icushim.c)

src/tasks/AppleAppBuilder/AppleAppBuilder.cs

@@ -182,7 +182,7 @@ public override bool Execute()
 
         if (GenerateXcodeProject)
         {
-            Xcode generator = new Xcode(TargetOS);
+            Xcode generator = new Xcode(TargetOS, Arch);
             generator.EnableRuntimeLogging = EnableRuntimeLogging;
 
             XcodeProjectPath = generator.GenerateXCode(ProjectName, MainLibraryFileName, assemblerFiles,