6983520: java/io/pathNames/GeneralWin32.java fails with jdk7-b108 (win)

Reviewed-by: sherman

src/windows/native/java/io/WinNTFileSystem_md.c

@@ -815,7 +815,7 @@ Java_java_io_WinNTFileSystem_getDriveDirectory(JNIEnv *env, jobject this,
                                                jint drive)
 {
     jstring ret = NULL;
-    jchar *p = _wgetdcwd(drive, NULL, MAX_PATH);
+    jchar *p = currentDir(drive);
     jchar *pf = p;
     if (p == NULL) return NULL;
     if (iswalpha(*p) && (p[1] == L':')) p += 2;

src/windows/native/java/io/io_util_md.c

@@ -66,6 +66,25 @@ fileToNTPath(JNIEnv *env, jobject file, jfieldID id) {
     return pathToNTPath(env, path, JNI_FALSE);
 }
 
+/* Returns the working directory for the given drive, or NULL */
+WCHAR*
+currentDir(int di) {
+    UINT dt;
+    WCHAR root[4];
+    // verify drive is valid as _wgetdcwd in the VC++ 2010 runtime
+    // library does not handle invalid drives.
+    root[0] = L'A' + (WCHAR)(di - 1);
+    root[1] = L':';
+    root[2] = L'\\';
+    root[3] = L'\0';
+    dt = GetDriveTypeW(root);
+    if (dt == DRIVE_UNKNOWN || dt == DRIVE_NO_ROOT_DIR) {
+        return NULL;
+    } else {
+        return _wgetdcwd(di, NULL, MAX_PATH);
+    }
+}
+
 /* We cache the length of current working dir here to avoid
    calling _wgetcwd() every time we need to resolve a relative
    path. This piece of code needs to be revisited if chdir
@@ -83,7 +102,7 @@ currentDirLength(const WCHAR* ps, int pathlen) {
         if ((d >= L'a') && (d <= L'z')) di = d - L'a' + 1;
         else if ((d >= L'A') && (d <= L'Z')) di = d - L'A' + 1;
         else return 0; /* invalid drive name. */
-        dir = _wgetdcwd(di, NULL, MAX_PATH);
+        dir = currentDir(di);
         if (dir != NULL){
             dirlen = wcslen(dir);
             free(dir);

src/windows/native/java/io/io_util_md.h

@@ -33,6 +33,7 @@
 WCHAR* pathToNTPath(JNIEnv *env, jstring path, jboolean throwFNFE);
 WCHAR* fileToNTPath(JNIEnv *env, jobject file, jfieldID id);
 WCHAR* getPrefixed(const WCHAR* path, int pathlen);
+WCHAR* currentDir(int di);
 int currentDirLength(const WCHAR* path, int pathlen);
 void fileOpen(JNIEnv *env, jobject this, jstring path, jfieldID fid, int flags);
 int handleAvailable(jlong fd, jlong *pbytes);

test/java/io/pathNames/GeneralWin32.java

@@ -22,7 +22,7 @@
  */
 
 /* @test
-   @bug 4032066 4039597 4046914 4054511 4065189 4109131 4875229
+   @bug 4032066 4039597 4046914 4054511 4065189 4109131 4875229 6983520
    @summary General exhaustive test of win32 pathname handling
    @author Mark Reinhold