Add System.Native APIs needed by NativeAOT (#62571)

Porting files over from runtimelab branch - no changes to what was there.

src/native/libs/Common/pal_config.h.in

@@ -45,7 +45,9 @@
 #cmakedefine01 HAVE_TIOCGWINSZ
 #cmakedefine01 HAVE_SCHED_GETAFFINITY
 #cmakedefine01 HAVE_SCHED_SETAFFINITY
+#cmakedefine01 HAVE_SCHED_GETCPU
 #cmakedefine01 HAVE_PTHREAD_SETCANCELSTATE
+#cmakedefine01 HAVE_GNU_LIBNAMES_H
 #cmakedefine01 HAVE_ARC4RANDOM_BUF
 #cmakedefine01 KEVENT_HAS_VOID_UDATA
 #cmakedefine01 HAVE_FDS_BITS

src/native/libs/System.Native/CMakeLists.txt

@@ -4,11 +4,18 @@ if (NOT CLR_CMAKE_TARGET_MACCATALYST AND NOT CLR_CMAKE_TARGET_IOS AND NOT CLR_CM
     add_definitions(-DHAS_CONSOLE_SIGNALS)
 endif ()
 
+if (CLR_CMAKE_HOST_ALPINE_LINUX)
+    # Fix up the thread stack size for MUSL to more reasonable size.
+    # TODO: https://github.com/dotnet/runtimelab/issues/791
+    add_definitions(-DENSURE_PRIMARY_STACK_SIZE)
+endif ()
+
 if (CLR_CMAKE_TARGET_OSX)
     add_definitions(-D_DARWIN_C_SOURCE)
 endif ()
 
 set(NATIVE_SOURCES
+    pal_dynamicload.c
     pal_errno.c
     pal_interfaceaddresses.c
     pal_io.c

src/native/libs/System.Native/entrypoints.c

@@ -7,6 +7,7 @@
 #include "pal_autoreleasepool.h"
 #include "pal_console.h"
 #include "pal_datetime.h"
+#include "pal_dynamicload.h"
 #include "pal_environment.h"
 #include "pal_errno.h"
 #include "pal_interfaceaddresses.h"
@@ -235,6 +236,12 @@ static const Entry s_sysNative[] =
     DllImportEntry(SystemNative_LowLevelMonitor_Wait)
     DllImportEntry(SystemNative_LowLevelMonitor_TimedWait)
     DllImportEntry(SystemNative_LowLevelMonitor_Signal_Release)
+    DllImportEntry(SystemNative_LoadLibrary)
+    DllImportEntry(SystemNative_GetProcAddress)
+    DllImportEntry(SystemNative_FreeLibrary)
+    DllImportEntry(SystemNative_SchedGetCpu)
+    DllImportEntry(SystemNative_Exit)
+    DllImportEntry(SystemNative_Abort)
     DllImportEntry(SystemNative_UTimensat)
     DllImportEntry(SystemNative_GetTimestamp)
     DllImportEntry(SystemNative_GetCpuUtilization)
@@ -253,6 +260,7 @@ static const Entry s_sysNative[] =
     DllImportEntry(SystemNative_PWrite)
     DllImportEntry(SystemNative_PReadV)
     DllImportEntry(SystemNative_PWriteV)
+    DllImportEntry(SystemNative_RuntimeThread_CreateThread)
     DllImportEntry(SystemNative_EnablePosixSignalHandling)
     DllImportEntry(SystemNative_DisablePosixSignalHandling)
     DllImportEntry(SystemNative_HandleNonCanceledPosixSignal)

src/native/libs/System.Native/pal_dynamicload.c

@@ -0,0 +1,52 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+#include "pal_config.h"
+#include "pal_dynamicload.h"
+
+#include <dlfcn.h>
+#include <string.h>
+
+#if HAVE_GNU_LIBNAMES_H
+#include <gnu/lib-names.h>
+#endif
+
+void* SystemNative_LoadLibrary(const char* filename)
+{
+    // Check whether we have been requested to load 'libc'. If that's the case, then:
+    // * For Linux, use the full name of the library that is defined in <gnu/lib-names.h> by the
+    //   LIBC_SO constant. The problem is that calling dlopen("libc.so") will fail for libc even
+    //   though it works for other libraries. The reason is that libc.so is just linker script
+    //   (i.e. a test file).
+    //   As a result, we have to use the full name (i.e. lib.so.6) that is defined by LIBC_SO.
+    // * For macOS, use constant value absolute path "/usr/lib/libc.dylib".
+    // * For FreeBSD, use constant value "libc.so.7".
+    // * For rest of Unices, use constant value "libc.so".
+    if (strcmp(filename, "libc") == 0)
+    {
+#if defined(__APPLE__)
+        filename = "/usr/lib/libc.dylib";
+#elif defined(__FreeBSD__)
+        filename = "libc.so.7";
+#elif defined(LIBC_SO)
+        filename = LIBC_SO;
+#else
+        filename = "libc.so";
+#endif
+    }
+
+    return dlopen(filename, RTLD_LAZY);
+}
+
+void* SystemNative_GetProcAddress(void* handle, const char* symbol)
+{
+    // We're not trying to disambiguate between "symbol was not found" and "symbol found, but
+    // the value is null". .NET does not define a behavior for DllImports of null entrypoints,
+    // so we might as well take the "not found" path on the managed side.
+    return dlsym(handle, symbol);
+}
+
+void SystemNative_FreeLibrary(void* handle)
+{
+    dlclose(handle);
+}

src/native/libs/System.Native/pal_dynamicload.h

@@ -0,0 +1,13 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+#pragma once
+
+#include "pal_compiler.h"
+#include "pal_types.h"
+
+PALEXPORT void* SystemNative_LoadLibrary(const char* filename);
+
+PALEXPORT void* SystemNative_GetProcAddress(void* handle, const char* symbol);
+
+PALEXPORT void SystemNative_FreeLibrary(void* handle);

src/native/libs/System.Native/pal_threading.c

@@ -12,6 +12,9 @@
 #include <errno.h>
 #include <time.h>
 #include <sys/time.h>
+#if HAVE_SCHED_GETCPU
+#include <sched.h>
+#endif
 
 #if defined(TARGET_OSX)
 // So we can use the declaration of pthread_cond_timedwait_relative_np
@@ -214,3 +217,71 @@ void SystemNative_LowLevelMonitor_Signal_Release(LowLevelMonitor* monitor)
 
     (void)error; // unused in release build
 }
+
+int32_t SystemNative_RuntimeThread_CreateThread(uintptr_t stackSize, void *(*startAddress)(void*), void *parameter)
+{
+    bool result = false;
+    pthread_attr_t attrs;
+
+    int error = pthread_attr_init(&attrs);
+    if (error != 0)
+    {
+        // Do not call pthread_attr_destroy
+        return false;
+    }
+
+    error = pthread_attr_setdetachstate(&attrs, PTHREAD_CREATE_DETACHED);
+    assert(error == 0);
+
+#ifdef ENSURE_PRIMARY_STACK_SIZE
+    // TODO: https://github.com/dotnet/runtimelab/issues/791
+    if (stackSize == 0)
+    {
+        stackSize = 1536 * 1024;
+    }
+#endif
+
+    if (stackSize > 0)
+    {
+        if (stackSize < PTHREAD_STACK_MIN)
+        {
+            stackSize = PTHREAD_STACK_MIN;
+        }
+
+        error = pthread_attr_setstacksize(&attrs, stackSize);
+        if (error != 0) goto CreateThreadExit;
+    }
+
+    pthread_t threadId;
+    error = pthread_create(&threadId, &attrs, startAddress, parameter);
+    if (error != 0) goto CreateThreadExit;
+
+    result = true;
+
+CreateThreadExit:
+    error = pthread_attr_destroy(&attrs);
+    assert(error == 0);
+
+    return result;
+}
+
+int32_t SystemNative_SchedGetCpu()
+{
+#if HAVE_SCHED_GETCPU
+    return sched_getcpu();
+#else
+    return -1;
+#endif
+}
+
+__attribute__((noreturn))
+void SystemNative_Exit(int32_t exitCode)
+{
+    exit(exitCode);
+}
+
+__attribute__((noreturn))
+void SystemNative_Abort()
+{
+    abort();
+}

src/native/libs/System.Native/pal_threading.h

@@ -21,3 +21,11 @@ PALEXPORT void SystemNative_LowLevelMonitor_Wait(LowLevelMonitor* monitor);
 PALEXPORT int32_t SystemNative_LowLevelMonitor_TimedWait(LowLevelMonitor *monitor, int32_t timeoutMilliseconds);
 
 PALEXPORT void SystemNative_LowLevelMonitor_Signal_Release(LowLevelMonitor* monitor);
+
+PALEXPORT int32_t SystemNative_RuntimeThread_CreateThread(uintptr_t stackSize, void *(*startAddress)(void*), void *parameter);
+
+PALEXPORT int32_t SystemNative_SchedGetCpu(void);
+
+PALEXPORT __attribute__((noreturn)) void SystemNative_Exit(int32_t exitCode);
+
+PALEXPORT __attribute__((noreturn)) void SystemNative_Abort(void);

src/native/libs/configure.cmake

@@ -261,11 +261,20 @@ check_symbol_exists(
     "sched.h"
     HAVE_SCHED_SETAFFINITY)
 
+check_symbol_exists(
+    sched_getcpu
+    "sched.h"
+    HAVE_SCHED_GETCPU)
+
 check_symbol_exists(
     pthread_setcancelstate
     "pthread.h"
     HAVE_PTHREAD_SETCANCELSTATE)
 
+check_include_files(
+    gnu/lib-names.h
+    HAVE_GNU_LIBNAMES_H)
+
 check_symbol_exists(
     arc4random_buf
     "stdlib.h"