Setup $HOME/storage symlink for external symlink

At startup Termux now checks if there is external storage available,
and creates a private area on the external storage if one exists as
well as creating a symlink to the private are at $HOME/storage.

.idea/codeStyleSettings.xml

@@ -63,9 +63,7 @@
           </extensions>
         </Objective-C-extensions>
         <XML>
-          <option name="XML_KEEP_LINE_BREAKS" value="false" />
+          <option name="XML_LEGACY_SETTINGS_IMPORTED" value="true" />
-          <option name="XML_ALIGN_ATTRIBUTES" value="false" />
-          <option name="XML_SPACE_INSIDE_EMPTY_TAG" value="true" />
         </XML>
         <codeStyleSettings language="XML">
           <option name="FORCE_REARRANGE_MODE" value="1" />
@@ -79,7 +77,7 @@
                   <match>
                     <AND>
                       <NAME>xmlns:android</NAME>
-                      <XML_NAMESPACE />
+                      <XML_NAMESPACE>Namespace:</XML_NAMESPACE>
                     </AND>
                   </match>
                 </rule>
@@ -89,7 +87,7 @@
                   <match>
                     <AND>
                       <NAME>xmlns:.*</NAME>
-                      <XML_NAMESPACE />
+                      <XML_NAMESPACE>Namespace:</XML_NAMESPACE>
                     </AND>
                   </match>
                   <order>BY_NAME</order>

app/build.gradle

@@ -18,8 +18,8 @@ android {
         applicationId "com.termux"
         minSdkVersion 21
         targetSdkVersion 23
-        versionCode 21
+        versionCode 22
-        versionName "0.21"
+        versionName "0.22"
     }
 
     buildTypes {

app/src/main/java/com/termux/app/TermuxActivity.java

@@ -293,6 +293,8 @@ public final class TermuxActivity extends Activity implements ServiceConnection
 
 		mTerminalView.checkForTypeface();
 		mTerminalView.checkForColors();
+
+		TermuxInstaller.setupStorageSymlink(this);
 	}
 
 	/**

app/src/main/java/com/termux/app/TermuxInstaller.java

@@ -1,16 +1,5 @@
 package com.termux.app;
 
-import java.io.BufferedReader;
-import java.io.File;
-import java.io.FileOutputStream;
-import java.io.InputStreamReader;
-import java.net.MalformedURLException;
-import java.net.URL;
-import java.util.ArrayList;
-import java.util.List;
-import java.util.zip.ZipEntry;
-import java.util.zip.ZipInputStream;
-
 import android.app.Activity;
 import android.app.AlertDialog;
 import android.app.ProgressDialog;
@@ -26,6 +15,17 @@ import android.view.WindowManager;
 import com.termux.R;
 import com.termux.terminal.EmulatorDebug;
 
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.InputStreamReader;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipInputStream;
+
 /**
  * Install the Termux bootstrap packages if necessary by following the below steps:
  * 
@@ -200,4 +200,36 @@ final class TermuxInstaller {
 		}
 	}
 
+	public static void setupStorageSymlink(final Context context) {
+		final File[] dirs = context.getExternalFilesDirs(null);
+		if (dirs == null || dirs.length < 2) return;
+		new Thread() {
+			public void run() {
+				try {
+					final File externalDir = dirs[1];
+					File homeDir = new File(TermuxService.HOME_PATH);
+					homeDir.mkdirs();
+					File externalLink = new File(homeDir, "storage");
+
+					if (externalLink.exists()) {
+						if (externalLink.getCanonicalPath().equals(externalDir.getPath())) {
+							// Keeping existing link.
+							return;
+						} else {
+							// Removing old link to give place to new.
+							if (!externalLink.delete()) {
+								Log.e("termux", "Unable to remove old $HOME/storage to give place for new");
+								return;
+							}
+						}
+					}
+
+					Os.symlink(externalDir.getAbsolutePath(), externalLink.getAbsolutePath());
+				} catch (Exception e) {
+					Log.e("termux", "Error setting up link", e);
+				}
+			}
+		}.start();
+	}
+
 }

app/src/main/java/com/termux/terminal/TerminalEmulator.java

@@ -1444,7 +1444,7 @@ public final class TerminalEmulator {
 				final int linesToScrollArg = getArg0(1);
 				final int linesBetweenTopAndBottomMargins = mBottomMargin - mTopMargin;
 				final int linesToScroll = Math.min(linesBetweenTopAndBottomMargins, linesToScrollArg);
-				mScreen.blockCopy(0, mTopMargin, mColumns, linesBetweenTopAndBottomMargins - linesToScroll, 0, linesToScroll);
+				mScreen.blockCopy(0, mTopMargin, mColumns, linesBetweenTopAndBottomMargins - linesToScroll, 0, mTopMargin + linesToScroll);
 				blockClear(0, mTopMargin, mColumns, linesToScroll);
 			} else {
 				// "${CSI}${func};${startx};${starty};${firstrow};${lastrow}T" - initiate highlight mouse tracking.

app/src/test/java/com/termux/terminal/ScrollRegionTest.java

@@ -94,4 +94,8 @@ public class ScrollRegionTest extends TerminalTestCase {
 		withTerminalSized(3, 3).enterString("\033[?69h\033[0;2sABCD\0339").assertLinesAre("B  ", "D  ", "   ");
 	}
 
+	public void testScrollDownWithScrollRegion() {
+		withTerminalSized(2, 5).enterString("1\r\n2\r\n3\r\n4\r\n5").assertLinesAre("1 ", "2 ", "3 ", "4 ", "5 ");
+		enterString("\033[3r").enterString("\033[2T").assertLinesAre("1 ", "2 ", "  ", "  ", "3 ");
+	}
 }