[Android] Enable more code and tests (#871)

* [Android] Enable more code and tests

while disabling setting extended file attributes and a test creating a hard link,
features not normally allowed on Android.

* Remove incorrect WASI check

Author: finagolfin

Sources/FoundationEssentials/Data/Data+Reading.swift

@@ -34,7 +34,7 @@ import WASILibc
 func _fgetxattr(_ fd: Int32, _ name: UnsafePointer<CChar>!, _ value: UnsafeMutableRawPointer!, _ size: Int, _ position: UInt32, _ options: Int32) -> Int {
 #if canImport(Darwin)
     return fgetxattr(fd, name, value, size, position, options)
-#elseif canImport(Glibc) || canImport(Musl)
+#elseif canImport(Glibc) || canImport(Musl) || canImport(Android)
     return fgetxattr(fd, name, value, size)
 #else
     return -1
@@ -355,7 +355,7 @@ internal func readBytesFromFile(path inPath: PathOrURL, reportProgress: Bool, ma
     let localProgress = (reportProgress && Progress.current() != nil) ? Progress(totalUnitCount: Int64(fileSize)) : nil
 
     if fileSize == 0 {
-        #if os(Linux)
+        #if os(Linux) || os(Android)
         // Linux has some files that may report a size of 0 but actually have contents
         let chunkSize = 1024 * 4
         var buffer = malloc(chunkSize)!

Sources/FoundationEssentials/FileManager/FileManager+Files.swift

@@ -956,6 +956,8 @@ extension _FileManagerImpl {
                 #if os(WASI)
                 // WASI does not support extended attributes
                 throw CocoaError.errorWithFilePath(.featureUnsupported, path)
+                #elseif canImport(Android)
+                // Android doesn't allow setting this for normal apps, so just skip it.
                 #else
                 try Self._setAttributes(extendedAttrs, at: fileSystemRepresentation, followSymLinks: false)
                 #endif

Sources/FoundationEssentials/Platform.swift

@@ -192,7 +192,7 @@ extension Platform {
 extension Platform {
     @discardableResult
     package static func copyCString(dst: UnsafeMutablePointer<CChar>, src: UnsafePointer<CChar>, size: Int) -> Int {
-        #if canImport(Darwin)
+        #if canImport(Darwin) || canImport(Android)
         return strlcpy(dst, src, size)
         #else
         // Glibc doesn't support strlcpy
@@ -267,7 +267,7 @@ extension Platform {
             return String(cString: buffer.baseAddress!).standardizingPath
             #endif
         }
-#elseif os(Linux)
+#elseif os(Linux) || os(Android)
         // For Linux, read /proc/self/exe
         return try? FileManager.default.destinationOfSymbolicLink(
             atPath: "/proc/self/exe").standardizingPath

Sources/FoundationEssentials/ProcessInfo/ProcessInfo.swift

@@ -450,7 +450,7 @@ extension _ProcessInfo {
         var siInfo = SYSTEM_INFO()
         GetSystemInfo(&siInfo)
         return Int(siInfo.dwNumberOfProcessors)
-#elseif os(Linux) || os(FreeBSD)
+#elseif os(Linux) || os(FreeBSD) || canImport(Android)
         return Int(sysconf(Int32(_SC_NPROCESSORS_CONF)))
 #else
         return 1
@@ -467,7 +467,7 @@ extension _ProcessInfo {
             return 0
         }
         return Int(count)
-#elseif os(Linux) || os(FreeBSD)
+#elseif os(Linux) || os(FreeBSD) || canImport(Android)
         #if os(Linux)
         if let fsCount = Self.fsCoreCount() {
             return fsCount
@@ -561,7 +561,7 @@ extension _ProcessInfo {
             return 0
         }
         return totalMemoryKB * 1024
-#elseif os(Linux) || os(FreeBSD)
+#elseif os(Linux) || os(FreeBSD) || canImport(Android)
         var memory = sysconf(Int32(_SC_PHYS_PAGES))
         memory *= sysconf(Int32(_SC_PAGESIZE))
         return UInt64(memory)

Sources/FoundationEssentials/TimeZone/TimeZone_Cache.swift

@@ -158,7 +158,7 @@ struct TimeZoneCache : Sendable, ~Copyable {
                 }
             }
 
-#if os(Linux) && !os(WASI)
+#if os(Linux)
             // Try localtime
             tzset()
             var t = time(nil)

Tests/FoundationEssentialsTests/DataIOTests.swift

@@ -238,7 +238,7 @@ class DataIOTests : XCTestCase {
     }
 
     func test_zeroSizeFile() throws {
-        #if !os(Linux)
+        #if !os(Linux) && !os(Android)
         throw XCTSkip("This test is only applicable on Linux")
         #else
         // Some files in /proc report a file size of 0 bytes via a stat call

Tests/FoundationEssentialsTests/DataTests.swift

@@ -1837,7 +1837,7 @@ extension DataTests {
     }
 
     func testEOPNOTSUPP() throws {
-        #if !canImport(Darwin) && !os(Linux)
+        #if !canImport(Darwin) && !os(Linux) && !os(Android)
         throw XCTSkip("POSIXError.Code is not supported on this platform")
         #else
         // Opening a socket via open(2) on Darwin can result in the EOPNOTSUPP error code

Tests/FoundationEssentialsTests/FileManager/FileManagerTests.swift

@@ -23,6 +23,10 @@ import TestSupport
 @testable import Foundation
 #endif
 
+#if canImport(Android)
+import Android
+#endif
+
 extension FileManager {
     fileprivate var delegateCaptures: DelegateCaptures {
         (self.delegate as! CapturingFileManagerDelegate).captures
@@ -337,8 +341,13 @@ final class FileManagerTests : XCTestCase {
             XCTAssertTrue($0.delegateCaptures.isEmpty)
             try $0.linkItem(atPath: "foo", toPath: "bar")
             XCTAssertEqual($0.delegateCaptures.shouldLink, [.init("foo", "bar")])
+            #if os(Android) // Hard links are not normally allowed on Android.
+            XCTAssertEqual($0.delegateCaptures.shouldProceedAfterLinkError, [.init("foo", "bar", code: .fileWriteNoPermission)])
+            XCTAssertFalse($0.fileExists(atPath: "bar"))
+            #else
             XCTAssertEqual($0.delegateCaptures.shouldProceedAfterLinkError, [])
             XCTAssertTrue($0.fileExists(atPath: "bar"))
+            #endif
         }
 
         try FileManagerPlayground {

Tests/FoundationEssentialsTests/PredicateTests.swift

@@ -364,7 +364,7 @@ final class PredicateTests: XCTestCase {
     func testRegex_RegexBuilder() throws {
         #if !canImport(RegexBuilder)
         throw XCTSkip("RegexBuilder is unavavailable on this platform")
-        #elseif !os(Linux) && !FOUNDATION_FRAMEWORK
+        #elseif !os(Linux) && !os(Android) && !FOUNDATION_FRAMEWORK
         // Disable this test in swift-foundation macOS CI because of incorrect availability annotations in the StringProcessing module
         throw XCTSkip("This test is currently disabled on this platform")
         #else

Tests/FoundationEssentialsTests/ProcessInfoTests.swift

@@ -115,7 +115,7 @@ final class ProcessInfoTests : XCTestCase {
         let expectedMinMajorVersion = 2
         #endif
         XCTAssertGreaterThanOrEqual(version.majorVersion, expectedMinMajorVersion, "Unrealistic major system version")
-        #elseif os(Windows) || os(Linux)
+        #elseif os(Windows) || os(Linux) || os(Android)
         let minVersion = OperatingSystemVersion(majorVersion: 1, minorVersion: 0, patchVersion: 0)
         XCTAssertTrue(ProcessInfo.processInfo.isOperatingSystemAtLeast(minVersion))
         #else
@@ -171,7 +171,7 @@ final class ProcessInfoTests : XCTestCase {
     func testProcessName() {
 #if FOUNDATION_FRAMEWORK
         let targetName = "TestHost"
-#elseif os(Linux) || os(Windows)
+#elseif os(Linux) || os(Windows) || os(Android)
         let targetName = "swift-foundationPackageTests.xctest"
 #else
         let targetName = "xctest"