Add support for wasm32-unknown-emscripten platform

CMakeLists.txt

@@ -75,8 +75,8 @@ if(BUILD_SHARED_LIBS)
 endif()
 
 set(FOUNDATION_BUILD_NETWORKING_default ON)
-if(CMAKE_SYSTEM_NAME STREQUAL "WASI")
-    # Networking is not supported on WASI
+if(CMAKE_SYSTEM_NAME STREQUAL "WASI" OR CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
+    # Networking is not supported on WASI/Emscripten
     set(FOUNDATION_BUILD_NETWORKING_default OFF)
 endif()
 option(FOUNDATION_BUILD_NETWORKING "build FoundationNetworking"
@@ -149,8 +149,8 @@ endif()
 
 # System dependencies
 
-# We know libdispatch is always unavailable on WASI
-if(NOT CMAKE_SYSTEM_NAME STREQUAL "WASI")
+# We know libdispatch is always unavailable on WASI and Emscripten
+if(NOT CMAKE_SYSTEM_NAME STREQUAL "WASI" AND NOT CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
     find_package(LibRT)
     find_package(dispatch CONFIG)
     if(NOT dispatch_FOUND)

Sources/CoreFoundation/CFPlatform.c

@@ -22,7 +22,7 @@
     #include <mach-o/dyld.h>
 #endif
 
-#if TARGET_OS_WASI
+#if TARGET_OS_WASI && !defined(__EMSCRIPTEN__)
 #include <wasi/libc-environ.h>
 #include <wasi/api.h>
 #endif
@@ -191,7 +191,7 @@ const char *_CFProcessPath(void) {
         __CFprogname = __CFProcessPath;
     }
     return __CFProcessPath;
-#elif TARGET_OS_WASI
+#elif TARGET_OS_WASI && !defined(__EMSCRIPTEN__)
     __wasi_errno_t err;
     size_t argc;
     size_t argv_buf_size;
@@ -216,6 +216,11 @@ const char *_CFProcessPath(void) {
     free(argv);
     return __CFProcessPath;
 
+#elif defined(__EMSCRIPTEN__)
+    __CFProcessPath = "";
+    __CFprogname = __CFProcessPath;
+    return __CFProcessPath;
+
 #else // TARGET_OS_BSD
     char *argv0 = NULL;
 
@@ -1883,10 +1888,10 @@ CF_EXPORT char **_CFEnviron(void) {
     return *_NSGetEnviron();
 #elif TARGET_OS_WIN32
     return _environ;
-#elif TARGET_OS_WASI
+#elif TARGET_OS_WASI && !defined(__EMSCRIPTEN__)
     return __wasilibc_get_environ();
 #else
-#if TARGET_OS_BSD
+#if TARGET_OS_BSD || defined(__EMSCRIPTEN__)
     extern char **environ;
 #endif
     return environ;

Sources/CoreFoundation/CMakeLists.txt

@@ -117,13 +117,16 @@ target_precompile_headers(CoreFoundation PRIVATE internalInclude/CoreFoundation_
 
 target_link_libraries(CoreFoundation
     PRIVATE
-        _FoundationICU
-        dispatch)
+        _FoundationICU)
 
-if(CMAKE_SYSTEM_NAME STREQUAL "WASI")
-    # On WASI, we use vendored BlocksRuntime instead of the one from libdispatch
+if(NOT CMAKE_SYSTEM_NAME STREQUAL "WASI" AND NOT CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
+    target_link_libraries(CoreFoundation PRIVATE dispatch)
+endif()
+
+if(CMAKE_SYSTEM_NAME STREQUAL "WASI" OR CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
+    # On WASI/Emscripten, we use vendored BlocksRuntime instead of the one
+    # from libdispatch.
     add_subdirectory(BlockRuntime)
-    # Add BlocksRuntime object library to CoreFoundation static archive
     target_link_libraries(CoreFoundation PRIVATE BlocksRuntime)
 endif()
 

Sources/CoreFoundation/include/CFTargetConditionals.h

@@ -18,7 +18,10 @@
 
 */
 
-#if __has_include(<TargetConditionals.h>)
+// When cross-compiling for Emscripten or WASI on a macOS host, the system
+// TargetConditionals.h may be found via __has_include even with --sysroot set.
+// Exclude these targets so our custom definitions below are used instead.
+#if __has_include(<TargetConditionals.h>) && !defined(__EMSCRIPTEN__) && !defined(__wasi__)
 #include <TargetConditionals.h>
 #else
 
@@ -118,6 +121,16 @@
 #define TARGET_OS_ANDROID      0
 #define TARGET_OS_CYGWIN       0
 #define TARGET_OS_WASI         0
+#elif __EMSCRIPTEN__
+#define TARGET_OS_DARWIN       0
+#define TARGET_OS_LINUX        0
+#define TARGET_OS_WINDOWS      0
+#define TARGET_OS_BSD          0
+#define TARGET_OS_ANDROID      0
+#define TARGET_OS_CYGWIN       0
+// Emscripten shares the same CoreFoundation constraints as WASI
+// (no dispatch, no pthread, single-threaded, wasm32).
+#define TARGET_OS_WASI         1
 #elif __unix__
 #define TARGET_OS_DARWIN       0
 #define TARGET_OS_LINUX        0

Sources/CoreFoundation/include/ForSwiftFoundationOnly.h

@@ -38,15 +38,17 @@
 #define _CRT_NONSTDC_NO_DEPRECATE
 #include <Windows.h>
 #else
+#if __has_include(<fts.h>)
 #include <fts.h>
 #endif
+#endif
 #if __has_include(<unistd.h>)
 #include <unistd.h>
 #endif
 #if _POSIX_THREADS
 #include <pthread.h>
 #endif
-#if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__)) || defined(__wasi__)
+#if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__)) || defined(__wasi__) || defined(__EMSCRIPTEN__)
 #include <dirent.h>
 #endif
 

Sources/CoreFoundation/internalInclude/CoreFoundation_Prefix.h

@@ -17,7 +17,7 @@
 #include "CFTargetConditionals.h"
 #include "CFAvailability.h"
 
-#if TARGET_OS_WASI
+#if TARGET_OS_WASI || defined(__EMSCRIPTEN__)
 #define __HAS_DISPATCH__ 0
 #else
 #define __HAS_DISPATCH__ 1

Sources/Foundation/FileHandle.swift

@@ -34,6 +34,11 @@ import WASILibc
 fileprivate let _read = WASILibc.read(_:_:_:)
 fileprivate let _write = WASILibc.write(_:_:_:)
 fileprivate let _close = WASILibc.close(_:)
+#elseif canImport(EmscriptenLibc)
+@preconcurrency import EmscriptenLibc
+fileprivate let _read = EmscriptenLibc.read(_:_:_:)
+fileprivate let _write = EmscriptenLibc.write(_:_:_:)
+fileprivate let _close = EmscriptenLibc.close(_:)
 #elseif canImport(Android)
 @preconcurrency import Android
 fileprivate let _read = Android.read(_:_:_:)
@@ -1074,7 +1079,7 @@ open class Pipe: NSObject, @unchecked Sendable {
                                                closeOnDealloc: true)
         self.fileHandleForWriting = FileHandle(handle: hWritePipe!,
                                                closeOnDealloc: true)
-#elseif os(WASI)
+#elseif os(WASI) || os(Emscripten)
         NSUnsupported()
 #else
         /// the `pipe` system call creates two `fd` in a malloc'ed area

Sources/Foundation/FileManager+POSIX.swift

@@ -145,6 +145,9 @@ extension FileManager {
             }
             fd += 1
         }
+#elseif os(Emscripten)
+        // Emscripten doesn't have WASI preopens or getfsstat
+        return nil
 #else
 #error("Requires a platform-specific implementation")
 #endif
@@ -153,8 +156,11 @@ extension FileManager {
 
     internal func _attributesOfFileSystemIncludingBlockSize(forPath path: String) throws -> (attributes: [FileAttributeKey : Any], blockSize: UInt64?) {
     #if os(WASI)
-        // WASI doesn't have statvfs
+        // WASI does not have statvfs
         throw _NSErrorWithErrno(ENOTSUP, reading: true, path: path)
+    #elseif os(Emscripten)
+        // Emscripten does not have statvfs
+        throw _NSErrorWithErrno(EmscriptenLibc.ENOTSUP, reading: true, path: path)
     #else
         var result: [FileAttributeKey:Any] = [:]
         var finalBlockSize: UInt64?
@@ -315,8 +321,10 @@ extension FileManager {
         var _url : URL
         var _options : FileManager.DirectoryEnumerationOptions
         var _errorHandler : ((URL, Error) -> Bool)?
+#if !os(Emscripten) // Emscripten doesn't have fts.h
         var _stream : UnsafeMutablePointer<FTS>? = nil
         var _current : UnsafeMutablePointer<FTSENT>? = nil
+#endif
         var _rootError : Error? = nil
         var _gotRoot : Bool = false
 
@@ -327,6 +335,9 @@ extension FileManager {
             _options = options
             _errorHandler = errorHandler
 
+#if os(Emscripten)
+            _rootError = _NSErrorWithErrno(ENOSYS, reading: true, url: url)
+#else
             let fm = FileManager.default
             do {
                 guard fm.fileExists(atPath: _url.path) else { throw _NSErrorWithErrno(ENOENT, reading: true, url: url) }
@@ -343,15 +354,26 @@ extension FileManager {
             } catch {
                 _rootError = error
             }
+#endif
         }
 
         deinit {
+#if !os(Emscripten)
             if let stream = _stream {
                 fts_close(stream)
             }
+#endif
         }
 
         override func nextObject() -> Any? {
+#if os(Emscripten)
+            if let error = _rootError {
+                if let handler = _errorHandler {
+                    let _ = handler(_url, error)
+                }
+            }
+            return nil
+#else
             func match(filename: String, to options: DirectoryEnumerationOptions, isDir: Bool) -> (Bool, Bool) {
                 var showFile = true
                 var skipDescendants = false
@@ -424,16 +446,23 @@ extension FileManager {
                 }
             }
             return nil
+#endif // !os(Emscripten)
         }
 
         override var level: Int {
+#if os(Emscripten)
+            return 0
+#else
             return Int(_current?.pointee.fts_level ?? 0)
+#endif
         }
 
         override func skipDescendants() {
+#if !os(Emscripten)
             if let stream = _stream, let current = _current {
                 fts_set(stream, current, FTS_SKIP)
             }
+#endif
         }
 
         override var directoryAttributes : [FileAttributeKey : Any]? {

Sources/Foundation/FileManager.swift

@@ -21,6 +21,8 @@ import WinSDK
 
 #if os(WASI)
 import WASILibc
+#elseif os(Emscripten)
+@preconcurrency import EmscriptenLibc
 #elseif canImport(Bionic)
 @preconcurrency import Bionic
 #endif

Sources/Foundation/Host.swift

@@ -95,7 +95,7 @@ open class Host: NSObject {
             return "localhost"
         }
         return String(cString: hostname)
-#elseif os(WASI) // WASI does not have uname
+#elseif os(WASI) || os(Emscripten) // WASI/Emscripten do not have uname
         return "localhost"
 #else
         let hname = UnsafeMutablePointer<Int8>.allocate(capacity: Int(NI_MAXHOST))
@@ -176,7 +176,7 @@ open class Host: NSObject {
         }
         _names = [info]
         _resolved = true
-#elseif os(WASI) // WASI does not have getifaddrs
+#elseif os(WASI) || os(Emscripten) // WASI/Emscripten do not have getifaddrs
         _names = [info]
         _resolved = true
 #else
@@ -276,7 +276,7 @@ open class Host: NSObject {
 
           _resolved = true
         }
-#elseif os(WASI) // WASI does not have getaddrinfo
+#elseif os(WASI) || os(Emscripten) // WASI/Emscripten do not have getaddrinfo
         if let info = _info {
             _names = [info]
             _resolved = true

Sources/Foundation/JSONSerialization.swift

@@ -274,7 +274,7 @@ open class JSONSerialization : NSObject {
 
     }
 
-#if !os(WASI)
+#if !os(WASI) && !os(Emscripten)
     /* Write JSON data into a stream. The stream should be opened and configured. The return value is the number of bytes written to the stream, or 0 on error. All other behavior of this method is the same as the dataWithJSONObject:options:error: method.
      */
     open class func writeJSONObject(_ obj: Any, toStream stream: OutputStream, options opt: WritingOptions) throws -> Int {

Sources/Foundation/NSArray.swift

@@ -446,7 +446,7 @@ open class NSArray : NSObject, NSCopying, NSMutableCopying, NSSecureCoding, NSCo
         return objects
     }
 
-#if !os(WASI)
+#if !os(WASI) && !os(Emscripten)
     open func write(to url: URL) throws {
         let pListData = try PropertyListSerialization.data(fromPropertyList: self, format: .xml, options: 0)
         try pListData.write(to: url, options: .atomic)

Sources/Foundation/NSCalendar.swift

@@ -866,7 +866,7 @@ open class NSCalendar : NSObject, NSCopying, NSSecureCoding {
 
 }
 
-#if !os(WASI)
+#if !os(WASI) && !os(Emscripten)
 // This notification is posted through [NSNotificationCenter defaultCenter]
 // when the system day changes. Register with "nil" as the object of this
 // notification. If the computer/device is asleep when the day changed,

Sources/Foundation/NSData.swift

@@ -8,7 +8,7 @@
 //
 
 @_implementationOnly import CoreFoundation
-#if !os(WASI)
+#if !os(WASI) && !os(Emscripten)
 import Dispatch
 #endif
 #if canImport(Android)
@@ -272,7 +272,7 @@ open class NSData : NSObject, NSCopying, NSMutableCopying, NSSecureCoding {
             return isEqual(to: data._swiftObject)
         }
 
-#if !os(WASI)
+#if !os(WASI) && !os(Emscripten)
         if let data = value as? DispatchData {
             if data.count != length {
                 return false
@@ -430,10 +430,10 @@ open class NSData : NSObject, NSCopying, NSMutableCopying, NSSecureCoding {
         }
 
         let fm = FileManager.default
-#if os(WASI)
-        // WASI does not have permission concept
+#if os(WASI) || os(Emscripten)
+        // WASI/Emscripten do not have permission concept
         let permissions: Int? = nil
-        // ReadingOptions.atomic won't be specified on WASI as it's marked unavailable
+        // ReadingOptions.atomic won't be specified as it's marked unavailable
         var atomicWrite: Bool { false }
 #else
         let permissions = try? fm.attributesOfItem(atPath: path)[.posixPermissions] as? Int
@@ -475,6 +475,8 @@ open class NSData : NSObject, NSCopying, NSMutableCopying, NSSecureCoding {
             let createMode = Int(Musl.S_IRUSR) | Int(Musl.S_IWUSR) | Int(Musl.S_IRGRP) | Int(Musl.S_IWGRP) | Int(Musl.S_IROTH) | Int(Musl.S_IWOTH)
 #elseif canImport(WASILibc)
             let createMode = Int(WASILibc.S_IRUSR) | Int(WASILibc.S_IWUSR) | Int(WASILibc.S_IRGRP) | Int(WASILibc.S_IWGRP) | Int(WASILibc.S_IROTH) | Int(WASILibc.S_IWOTH)
+#elseif canImport(EmscriptenLibc)
+            let createMode = Int(EmscriptenLibc.S_IRUSR) | Int(EmscriptenLibc.S_IWUSR) | Int(EmscriptenLibc.S_IRGRP) | Int(EmscriptenLibc.S_IWGRP) | Int(EmscriptenLibc.S_IROTH) | Int(EmscriptenLibc.S_IWOTH)
 #elseif canImport(Android)
             let createMode = Int(Android.S_IRUSR) | Int(Android.S_IWUSR) | Int(Android.S_IRGRP) | Int(Android.S_IWGRP) | Int(Android.S_IROTH) | Int(Android.S_IWOTH)
 #endif
@@ -490,11 +492,11 @@ open class NSData : NSObject, NSCopying, NSMutableCopying, NSSecureCoding {
 
     /// Writes the data object's bytes to the file specified by a given path.
     /// NOTE: the 'atomically' flag is ignored if the url is not of a type the supports atomic writes
-    #if os(WASI)
-    @available(*, unavailable, message: "WASI does not support atomic file-writing as it does not have temporary directories")
+    #if os(WASI) || os(Emscripten)
+    @available(*, unavailable, message: "Atomic file-writing is not available on this platform")
     #endif
     open func write(toFile path: String, atomically useAuxiliaryFile: Bool) -> Bool {
-        #if os(WASI)
+        #if os(WASI) || os(Emscripten)
         // WASI does not support atomic file-writing as it does not have temporary directories
         return false
         #else
@@ -509,11 +511,11 @@ open class NSData : NSObject, NSCopying, NSMutableCopying, NSSecureCoding {
 
     /// Writes the data object's bytes to the location specified by a given URL.
     /// NOTE: the 'atomically' flag is ignored if the url is not of a type the supports atomic writes
-    #if os(WASI)
-    @available(*, unavailable, message: "WASI does not support atomic file-writing as it does not have temporary directories")
+    #if os(WASI) || os(Emscripten)
+    @available(*, unavailable, message: "Atomic file-writing is not available on this platform")
     #endif
     open func write(to url: URL, atomically: Bool) -> Bool {
-        #if os(WASI)
+        #if os(WASI) || os(Emscripten)
         // WASI does not support atomic file-writing as it does not have temporary directories
         return false
         #else