Sys props (#1218)

* Set os.name system property

I noticed that scala.util.Properties.isMac didn't work because the
"os.name" system property wasn't set. I added this functionality for OSX
and Linux, but not windows because I don't know what it's supposed to
run. I only set the version for Linux because uname can't reliably used
to get the os.version string. I add support for that in a subsequent
commit, but it requires adding objective c support to the toolchain,
which I imagine may be contentious.

Bonus: move up initializing of streams so that println may be used in
loadProperties

* Remove unused private method in java.io.File

This was left behind in 40dd654.

* Move platform specific code into platform.c

We want to move away from having portable code implemented with runtime
branching, so I moved the setting of the os.name (and version on linux)
into platform.c.

I also added the java.io.tmpdir system property on all platforms. The
semantics are different than the jvm on osx (which uses a user
specific path that can only be accessed using objective c apis in the
foundation framework). Instead of the user specific temp directory, it
just uses /tmp, which is probably fine for most applications. It also
isn't possible to precisely determine the os version on osx without
shelling out to the `sw_vers` command or using different objective c
apis from the foundation framework. For now, we'll just leave the os
version blank on osx (and windows -- there are different issues with
getting this to work correctly on windows and right now there seem to
be very few windows users of scala native).

javalib/src/main/scala/java/io/File.scala

@@ -540,14 +540,4 @@ object File {
                                minLength = true,
                                throwOnError = true)
 
-  private def tempDir(): File = {
-    val dir = getenv(c"TMPDIR")
-    if (dir == null) {
-      new File(System.getProperty("java.io.tmpdir") match {
-        case null => "/tmp"
-        case d    => d
-      })
-    } else new File(fromCString(dir))
-  }
-
 }

javalib/src/main/scala/java/lang/System.scala

@@ -4,6 +4,8 @@ import java.io._
 import java.util.{Collections, HashMap, Map, Properties}
 import scala.scalanative.native._
 import scala.scalanative.posix.unistd
+import scala.scalanative.posix.sys.utsname._
+import scala.scalanative.posix.sys.uname._
 import scala.scalanative.runtime.time
 import scala.scalanative.runtime.Platform
 import scala.scalanative.runtime.GC
@@ -73,7 +75,18 @@ object System {
     sysProps
   }
 
-  private var systemProperties = loadProperties()
+  var in: InputStream =
+    new FileInputStream(FileDescriptor.in)
+  var out: PrintStream =
+    new PrintStream(new FileOutputStream(FileDescriptor.out))
+  var err: PrintStream =
+    new PrintStream(new FileOutputStream(FileDescriptor.err))
+
+  private val systemProperties = loadProperties()
+  Platform.setOSProps(
+    CFunctionPtr.fromFunction2((key: CString, value: CString) => {
+      systemProperties.setProperty(fromCString(key), fromCString(value));
+    }))
 
   def lineSeparator(): String = {
     if (Platform.isWindows) "\r\n"
@@ -100,13 +113,6 @@ object System {
   def getenv(): Map[String, String] = envVars
   def getenv(key: String): String   = envVars.get(key)
 
-  var in: InputStream =
-    new FileInputStream(FileDescriptor.in)
-  var out: PrintStream =
-    new PrintStream(new FileOutputStream(FileDescriptor.out))
-  var err: PrintStream =
-    new PrintStream(new FileOutputStream(FileDescriptor.err))
-
   def setIn(in: InputStream): Unit =
     this.in = in
 

nativelib/src/main/resources/dirent.c

@@ -11,33 +11,15 @@ struct scalanative_dirent {
     short d_type;
 };
 
-int scalanative_dt_unknown() {
-  return DT_UNKNOWN;
-}
-int scalanative_dt_fifo() {
-  return DT_FIFO;
-}
-int scalanative_dt_chr() {
-  return DT_CHR;
-}
-int scalanative_dt_dir() {
-  return DT_DIR;
-}
-int scalanative_dt_blk() {
-  return DT_BLK;
-}
-int scalanative_dt_reg() {
-  return DT_REG;
-}
-int scalanative_dt_lnk() {
-  return DT_LNK;
-}
-int scalanative_dt_sock() {
-  return DT_SOCK;
-}
-int scalanative_dt_wht() {
-  return DT_WHT;
-}
+int scalanative_dt_unknown() { return DT_UNKNOWN; }
+int scalanative_dt_fifo() { return DT_FIFO; }
+int scalanative_dt_chr() { return DT_CHR; }
+int scalanative_dt_dir() { return DT_DIR; }
+int scalanative_dt_blk() { return DT_BLK; }
+int scalanative_dt_reg() { return DT_REG; }
+int scalanative_dt_lnk() { return DT_LNK; }
+int scalanative_dt_sock() { return DT_SOCK; }
+int scalanative_dt_wht() { return DT_WHT; }
 
 DIR *scalanative_opendir(const char *name) { return opendir(name); }
 
@@ -55,10 +37,13 @@ int scalanative_readdir(DIR *dirp, struct scalanative_dirent *buf) {
         scalanative_dirent_init(orig_buf, buf);
         return 0;
     } else {
-        switch(errno) {
-          case EBADF: return EBADF;
-          case EFAULT: return EFAULT;
-          case EIO: return EIO;
+        switch (errno) {
+        case EBADF:
+            return EBADF;
+        case EFAULT:
+            return EFAULT;
+        case EIO:
+            return EIO;
         }
         return -1;
     }

nativelib/src/main/resources/optional/re2.cpp

@@ -149,9 +149,9 @@ int64_t scalanative_cre2_opt_max_mem(scalanative_cre2_options_t *opt) {
     return TO_OPT(opt)->max_mem();
 }
 
-    /** --------------------------------------------------------------------
-     ** Precompiled regular expressions objects.
-     ** ----------------------------------------------------------------- */
+/** --------------------------------------------------------------------
+ ** Precompiled regular expressions objects.
+ ** ----------------------------------------------------------------- */
 
 #define TO_RE2(re) (reinterpret_cast<RE2 *>(re))
 #define TO_CONST_RE2(re) (reinterpret_cast<const RE2 *>(re))

nativelib/src/main/resources/platform.c

@@ -1,7 +1,17 @@
 #ifdef _WIN32
 #include <Windows.h>
+#else
+#include <sys/utsname.h>
 #endif
 
+int scalanative_platform_is_mac() {
+#ifdef __APPLE__
+    return 1;
+#else
+    return 0;
+#endif
+}
+
 int scalanative_platform_is_windows() {
 #ifdef _WIN32
     return 1;
@@ -33,3 +43,26 @@ int scalanative_little_endian() {
     int n = 1;
     return (*(char *)&n);
 }
+
+void scalanative_set_os_props(void (*add_prop)(const char *, const char *)) {
+#ifdef _WIN32
+    add_prop("os.name", "Windows (Unknown version)");
+    wchar_t wcharPath[MAX_PATH];
+    char path[MAX_PATH];
+    if (GetTempPathW(MAX_PATH, wcharPath) &&
+        wcstombs(path, wcharPath, MAX_PATH) != -1) {
+        add_prop("java.io.tmpdir", (const char *)path);
+    }
+#else
+#ifdef __APPLE__
+    add_prop("os.name", "Mac OS X");
+#else
+    struct utsname name;
+    if (uname(&name) == 0) {
+        add_prop("os.name", name.sysname);
+        add_prop("os.version", name.release);
+    }
+#endif
+    add_prop("java.io.tmpdir", "/tmp");
+#endif
+}

nativelib/src/main/resources/posix/sys/uname.c

@@ -0,0 +1,30 @@
+#include <sys/utsname.h>
+#include <string.h>
+
+#define NAMELEN 256
+struct scalanative_utsname {
+    char sysname[NAMELEN];
+    char nodename[NAMELEN];
+    char release[NAMELEN];
+    char version[NAMELEN];
+    char machine[NAMELEN];
+};
+#undef NAMELEN
+#define SET_FIELD(x, y)                                                        \
+    do {                                                                       \
+        int len = strlen(y);                                                   \
+        memcpy(x, y, len);                                                     \
+    } while (0);
+
+int scalanative_uname(struct scalanative_utsname *scalanative_utsname) {
+    struct utsname utsname;
+    int res = uname(&utsname);
+    if (res == 0) {
+        SET_FIELD(&scalanative_utsname->sysname, utsname.sysname)
+        SET_FIELD(&scalanative_utsname->nodename, utsname.nodename)
+        SET_FIELD(&scalanative_utsname->release, utsname.release)
+        SET_FIELD(&scalanative_utsname->version, utsname.version)
+        SET_FIELD(&scalanative_utsname->machine, utsname.machine)
+    }
+    return res;
+}

nativelib/src/main/scala/scala/scalanative/posix/sys/utsname.scala

@@ -0,0 +1,21 @@
+package scala.scalanative.posix.sys
+
+import scala.scalanative.native._
+
+@extern
+object utsname {
+  type _256        = Nat.Digit[Nat._2, Nat.Digit[Nat._5, Nat._6]]
+  private type str = CArray[Byte, _256]
+  type utsname     = CStruct5[str, str, str, str, str]
+  @extern def uname(utsname: Ptr[utsname]): CInt = extern
+}
+
+object uname {
+  implicit class utsnameOps(val c: Ptr[utsname.utsname]) {
+    def sysname  = fromCString(c._1.cast[Ptr[CChar]])
+    def nodename = fromCString(c._2.cast[Ptr[CChar]])
+    def release  = fromCString(c._3.cast[Ptr[CChar]])
+    def version  = fromCString(c._4.cast[Ptr[CChar]])
+    def machine  = fromCString(c._5.cast[Ptr[CChar]])
+  }
+}

nativelib/src/main/scala/scala/scalanative/runtime/Platform.scala

@@ -1,10 +1,20 @@
 package scala.scalanative
 package runtime
 
-import scala.scalanative.native.{CString, extern, name}
+import scala.scalanative.native.{
+  CInt,
+  CFunctionPtr2,
+  CString,
+  Ptr,
+  extern,
+  name
+}
 
 @extern
 object Platform {
+  @name("scalanative_platform_is_mac")
+  def isMac(): Boolean = extern
+
   @name("scalanative_platform_is_windows")
   def isWindows(): Boolean = extern
 
@@ -16,4 +26,8 @@ object Platform {
 
   @name("scalanative_little_endian")
   def littleEndian(): Boolean = extern
+
+  @name("scalanative_set_os_props")
+  def setOSProps(addProp: CFunctionPtr2[CString, CString, Unit]): Unit =
+    extern
 }