Update Android port

* INSTALL.android: Update.
* build-aux/ndk-build-helper-1.mk: Fix typo.
* configure.ac: Enable --with-json on Android.
* cross/ndk-build/ndk-build-shared-library.mk:
(NDK_CFLAGS_$(LOCAL_MODULE)):
(LOCAL_MODULE_FILENAME):
* cross/ndk-build/ndk-build-static-library.mk:
(ALL_OBJECT_FILES$(LOCAL_MODULE)):
(LOCAL_MODULE_FILENAME): Recursively resolve dependencies.
* cross/ndk-build/ndk-resolve.mk: New function.

* doc/emacs/android.texi (Android Startup): Document how Emacs
is dumped during initial startup.

* java/Makefile.in (filename): Fix build with multiple shared
libraries.
* java/README: Improve commentary.
* java/org/gnu/emacs/EmacsApplication.java (onCreate): Look and
set dump file.
* java/org/gnu/emacs/EmacsNative.java (EmacsNative): New
function getFingerprint.
* java/org/gnu/emacs/EmacsPreferencesActivity.java (onCreate):
Add option to erase the dump file.
* java/org/gnu/emacs/EmacsService.java (browseUrl): New
function.
* java/org/gnu/emacs/EmacsThread.java (run): Specify dump file
if found.
* lisp/loadup.el: Always dump during loadup on Android.

* lisp/net/browse-url.el (browse-url--browser-defcustom-type):
(browse-url-default-browser):
(browse-url-default-android-browser): New browse url type.

* m4/ndk-build.m4 (ndk_package_map): Map jansson to libjansson.
* src/android.c (struct android_emacs_service): New method
`browse_url'.
(getFingerprint): New function.
(android_init_emacs_service): Initialize new method.
(android_browse_url): New function.

* src/android.h: Update prototypes.

* src/androidselect.c (Fandroid_browse_url): New function.
(syms_of_androidselect): Define it.

* src/emacs.c (load_pdump): Don't look in fancy places on
Android.
* src/pdumper.c (Fdump_emacs_portable): Allow dumping while
interactive on Android.
(syms_of_pdumper): New variable `pdumper-fingerprint'.

* src/sfntfont-android.c (sfntfont_android_composite_bitmap):
Fix unused variables.

INSTALL.android

@@ -148,6 +148,14 @@ work:
      (You must add LOCAL_EXPORT_CFLAGS := -I$(LOCAL_PATH) before
       its Android.mk includes $(BUILD_STATIC_LIBRARY))
 
+In addition, some Emacs dependencies provide `ndk-build' support
+themselves:
+
+  libjansson	- https://github.com/akheron/jansson
+    (You must add LOCAL_EXPORT_INCLUDES := $(LOCAL_C_INCLUDES) before
+     its Android.mk includes $(BUILD_SHARED_LIBRARY), then copy
+     android/jansson_config.h to android/jansson_private_config.h.)
+
 We anticipate that most untested non-trivial ndk-build dependencies
 will need adjustments in Emacs to work, as the Emacs build system
 which emulates ndk-build is in an extremely early state.
@@ -173,7 +181,7 @@ one awk script in build-awx, run during configure:
 
   build-aux/ndk-module-extract.awk
 
-six Makefiles in cross/ndk-build,
+seven Makefiles in cross/ndk-build,
 
   cross/ndk-build/ndk-build-shared-library.mk
   cross/ndk-build/ndk-build-static-library.mk
@@ -181,6 +189,7 @@ six Makefiles in cross/ndk-build,
   cross/ndk-build/ndk-clear-vars.mk
   cross/ndk-build/ndk-prebuilt-shared-library.mk
   cross/ndk-build/ndk-prebuilt-static-library.mk
+  cross/ndk-build/ndk-resolve.mk
 
 and finally, two more Makefiles in cross/ndk-build, generated by
 configure:
@@ -373,11 +382,27 @@ them.  The name under which the module is linked is the same as the
 Make target found on the sixth line of output from
 build-aux/ndk-build-helper.mk.
 
-However, none of the Makefiles in
+While the rules defined by the Makefiles in cross/ndk-build do not
-cross/ndk-build/ndk-build-shared-library.mk perform any kind of
+have their dependencies as prerequisites (with the assumption that the
-dependency resolution!	Instead, they only define rules to build
+ndk-build.m4 and the Makefiles in build-aux have already added all of
-individual modules, leaving dependency resolution up to the Makefiles
+the necessary targets to ndk-build.mk), dependency resolution is still
-in the `build-aux' directory.
+performed, as the CFLAGS and includes from dependencies must be
+appended to the module's CFLAGS.
+
+This is done by including cross/ndk-build/ndk-resolve.mk each time a
+shared or static library module is going to be built.  How is this
+done?
+
+First, ndk-resolve.mk saves the LOCAL_PATH, LOCAL_STATIC_LIBRARIES,
+LOCAL_SHARED_LIBRARIES, LOCAL_EXPORT_CFLAGS and
+LOCAL_EXPORT_C_INCLUDES from the module.
+
+Next, ndk-resolve loops through the dependencies the module has
+specified, appending its CFLAGS and includes to the command line for
+the current module.
+
+Then, that process is repeated for each such dependency which has not
+already been resolved, until all dependencies have been resolved.
 
 libpng is a very simple module, providing only a single shared object
 module.	 This module is named libpng_emacs.so and is eventually built

build-aux/ndk-build-helper-1.mk

@@ -33,7 +33,7 @@ NDK_$(LOCAL_MODULE)_SHARED_LIBRARIES := $(LOCAL_SHARED_LIBRARIES)
 
 $(info Building $(build_kind))
 $(info $(LOCAL_MODULE))
-$(info $(addprefix $(ANDROID_MODULE_DIRECTORY)?,$(LOCAL_SRC_FILES) $(LOCAL_SRC_FILES$(EMACS_ABI))))
+$(info $(addprefix $(ANDROID_MODULE_DIRECTORY)/,$(LOCAL_SRC_FILES) $(LOCAL_SRC_FILES$(EMACS_ABI))))
 
 $(info $(foreach dir,$(LOCAL_EXPORT_C_INCLUDE_DIRS) $(LOCAL_EXPORT_C_INCLUDES),-I$(dir)))
 $(info $(LOCAL_EXPORT_CFLAGS))

configure.ac

@@ -1045,6 +1045,7 @@ package will likely install on older systems but crash on startup.])
   passthrough="$passthrough --with-png=$with_png"
   passthrough="$passthrough --with-webp=$with_webp"
   passthrough="$passthrough --with-gif=$with_gif"
+  passthrough="$passthrough --with-json=$with_json"
 
   AS_IF([XCONFIGURE=android ANDROID_CC="$ANDROID_CC" \
          ANDROID_SDK="$android_sdk" android_abi=$android_abi \
@@ -1112,6 +1113,7 @@ if test "$ANDROID" = "yes"; then
     with_png=no
     with_webp=no
     with_gif=no
+    with_json=no
   fi
 
   with_xml2=no
@@ -1121,7 +1123,6 @@ if test "$ANDROID" = "yes"; then
   with_libsystemd=no
   with_cairo=no
   with_imagemagick=no
-  with_json=no
   with_tree_sitter=no
   with_xft=no
   with_harfbuzz=no

cross/ndk-build/ndk-build-shared-library.mk

@@ -44,11 +44,13 @@ ALL_OBJECT_FILES$(LOCAL_MODULE) += $(call objname,$(LOCAL_MODULE),$(basename $(1
 
 endef
 
-NDK_CFLAGS_$(LOCAL_MODULE)	 := $(addprefix -I,$(addprefix $(LOCAL_PATH),$(LOCAL_C_INCLUDES)))
+# Make sure to not add a prefix to local includes that already specify
-NDK_CFLAGS_$(LOCAL_MODULE)	 ::= -fPIC -iquote $(LOCAL_EXPORT_CFLAGS) $(LOCAL_PATH) $(LOCAL_CFLAGS)
+# $(LOCAL_PATH).
-NDK_LDFLAGS_$(LOCAL_MODULE)	 := $(LOCAL_LDLIBS)
+NDK_CFLAGS_$(LOCAL_MODULE)	 := $(addprefix -I,$(LOCAL_C_INCLUDES))
-NDK_LDFLAGS_$(LOCAL_MODULE)	 := $(LOCAL_LDFLAGS)
+NDK_CFLAGS_$(LOCAL_MODULE)	 += -fPIC -iquote $(LOCAL_PATH) $(LOCAL_EXPORT_CFLAGS) $(LOCAL_CFLAGS) $(LOCAL_CFLAGS$(NDK_BUILD_ARCH))
-ALL_OBJECT_FILES_$(LOCAL_MODULE) :=
+NDK_ASFLAGS_$(LOCAL_MODULE) := $(LOCAL_ASFLAGS) $(LOCAL_ASFLAGS_$(NDK_BUILD_ARCH))
+NDK_LDFLAGS_$(LOCAL_MODULE) := $(LOCAL_LDLIBS) $(LOCAL_LDFLAGS)
+ALL_OBJECT_FILES$(LOCAL_MODULE) :=
 
 ifeq ($(NDK_BUILD_ARCH)$(NDK_ARM_MODE),armarm)
 NDK_CFLAGS ::= -marm
@@ -74,8 +76,17 @@ endif
 
 LOCAL_MODULE_FILENAME := $(LOCAL_MODULE_FILENAME).so
 
+# Record this module's dependencies and exported includes and CFLAGS,
+# and then add that of its dependencies.
+
+include ndk-resolve.mk
+
 # Then define rules to build all objects.
-ALL_SOURCE_FILES = $(LOCAL_SRC_FILES)
+ALL_SOURCE_FILES = $(LOCAL_SRC_FILES) $(LOCAL_SRC_FILES_$(NDK_BUILD_ARCH))
+
+# This defines all dependencies.
+ALL_OBJECT_FILES$(LOCAL_MODULE) =
+
 $(foreach source,$(ALL_SOURCE_FILES),$(eval $(call single-object-target,$(source))))
 
 # Now define the rule to build the shared library.

cross/ndk-build/ndk-build-static-library.mk

@@ -43,11 +43,10 @@ endif
 ALL_OBJECT_FILES$(LOCAL_MODULE) += $(call objname,$(LOCAL_MODULE),$(basename $(1)))
 endef
 
-NDK_CFLAGS_$(LOCAL_MODULE)  := $(addprefix -I,$(addprefix $(LOCAL_PATH),$(LOCAL_C_INCLUDES)))
+NDK_CFLAGS_$(LOCAL_MODULE)  := $(addprefix -I,$(LOCAL_C_INCLUDES))
-NDK_CFLAGS_$(LOCAL_MODULE) ::= -iquote $(LOCAL_PATH) $(LOCAL_EXPORT_CFLAGS) $(LOCAL_CFLAGS) $(LOCAL_CFLAGS_$(NDK_BUILD_ARCH))
+NDK_CFLAGS_$(LOCAL_MODULE)  += -iquote $(LOCAL_PATH) $(LOCAL_EXPORT_CFLAGS) $(LOCAL_CFLAGS) $(LOCAL_CFLAGS_$(NDK_BUILD_ARCH))
-NDK_ASFLAGS_$(LOCAL_MODULE) ::= $(LOCAL_ASFLAGS) $(LOCAL_ASFLAGS_$(NDK_BUILD_ARCH))
+NDK_ASFLAGS_$(LOCAL_MODULE) := $(LOCAL_ASFLAGS) $(LOCAL_ASFLAGS_$(NDK_BUILD_ARCH))
-NDK_LDFLAGS_$(LOCAL_MODULE) := $(LOCAL_LDLIBS)
+NDK_LDFLAGS_$(LOCAL_MODULE) := $(LOCAL_LDLIBS) $(LOCAL_LDFLAGS)
-NDK_LDFLAGS_$(LOCAL_MODULE) := $(LOCAL_LDFLAGS)
 ALL_OBJECT_FILES$(LOCAL_MODULE) :=
 
 ifeq ($(NDK_BUILD_ARCH)$(NDK_ARM_MODE),armarm)
@@ -70,6 +69,11 @@ endif
 
 LOCAL_MODULE_FILENAME := $(LOCAL_MODULE_FILENAME).a
 
+# Record this module's dependencies and exported includes and CFLAGS,
+# and then add that of its dependencies.
+
+include ndk-resolve.mk
+
 # Then define rules to build all objects.
 ALL_SOURCE_FILES = $(LOCAL_SRC_FILES) $(LOCAL_SRC_FILES_$(NDK_BUILD_ARCH))
 

cross/ndk-build/ndk-resolve.mk

@@ -0,0 +1,47 @@
+# Copyright 2023 Free Software Foundation, Inc.
+
+# This file is part of GNU Emacs.
+
+# GNU Emacs is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# GNU Emacs is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
+
+# ndk-build works by including a bunch of Makefiles which set
+# variables, and then having those Makefiles include another makefile
+# which actually builds targets.
+
+# Save information.
+NDK_LOCAL_PATH_$(LOCAL_MODULE) := $(LOCAL_PATH)
+NDK_LOCAL_STATIC_LIBRARIES_$(LOCAL_MODULE) := $(LOCAL_STATIC_LIBRARIES) $(LOCAL_WHOLE_STATIC_LIBRARIES)
+NDK_LOCAL_SHARED_LIBRARIES_$(LOCAL_MODULE) := $(LOCAL_SHARED_LIBRARIES)
+NDK_LOCAL_EXPORT_CFLAGS_$(LOCAL_MODULE) := $(LOCAL_EXPORT_CFLAGS)
+NDK_LOCAL_EXPORT_C_INCLUDES_$(LOCAL_MODULE) := $(LOCAL_EXPORT_C_INCLUDES)
+
+# List of all dependencies resolved for this module thus far.
+# Used to avoid infinite recursion.
+NDK_RESOLVED_$(LOCAL_MODULE) :=
+
+define ndk-resolve
+
+ifeq ($(patsubst $(1),,$(NDK_RESOLVED$(LOCAL_MODULE))),$(NDK_RESOLVED$(LOCAL_MODULE)))
+NDK_RESOLVED$(LOCAL_MODULE) += $(1)
+NDK_CFLAGS_$(LOCAL_MODULE) += $(NDK_LOCAL_EXPORT_CFLAGS_$(1))
+NDK_CFLAGS_$(LOCAL_MODULE) += $(addprefix -I,$(NDK_LOCAL_EXPORT_C_INCLUDES_$(1)))
+
+$$(foreach module,$$(NDK_LOCAL_STATIC_LIBRARIES_$(1)),$$(eval $$(call ndk-resolve,$$(module))))
+$$(foreach module,$$(NDK_LOCAL_SHARED_LIBRARIES_$(1)),$$(eval $$(call ndk-resolve,$$(module))))
+endif
+
+endef
+
+$(foreach module,$(LOCAL_SHARED_LIBRARIES),$(eval $(call ndk-resolve,$(module))))
+$(foreach module,$(LOCAL_STATIC_LIBRARIES) $(LOCAL_WHOLE_STATIC_LIBRARIES),$(eval $(call ndk-resolve,$(module))))

doc/emacs/android.texi

@@ -69,10 +69,10 @@ application icon is clicked.
 
 @cindex ``adb logcat''
 
-During startup, Emacs will display messages in the system log buffer;
+  During startup, Emacs will display messages in the system log
-reading that buffer requires the Android Debug Bridge (@code{adb})
+buffer; reading that buffer requires the Android Debug Bridge
-utility to be installed on another computer; it cannot be read on the
+(@code{adb}) utility to be installed on another computer; it cannot be
-computer running Android itself.
+read on the computer running Android itself.
 
   After enabling the ``USB Debugging'' feature on the Android system,
 and connecting it via USB to another system with the @code{adb}
@@ -84,14 +84,31 @@ $ adb logcat | grep -E "(android_run_debug_thread|[Ee]macs)"
 @end example
 
 @cindex emacs -Q, android
-Since Android has no command line, there is normally no way to specify
+  Since Android has no command line, there is normally no way to
-command-line arguments.  However, Emacs can be started with the
+specify command-line arguments when starting Emacs.  However, Emacs
-equivalent of the @code{--quick} option (@pxref{Initial Options})
+can be started with the equivalent of the @code{--quick} option
-through a special preferences screen, which can be accessed through
+(@pxref{Initial Options}) through a special preferences screen, which
-the Emacs ``app info'' page in the system settings application.
+can be accessed through the Emacs ``app info'' page in the system
+settings application.
 
-Consult the manufacturer of your device for more details, as how to do
+  Consult the manufacturer of your device for more details, as how to
-this varies by device.
+do this varies by device.
+
+@cindex dumping, android
+  The first time any given copy of Emacs starts on a device, it spends
+a while loading the preloaded Lisp files which normally come with
+Emacs.  This produces a ``dump file'' (@pxref{Initial Options}) in the
+files directory, containing an identifier unique to this copy of
+Emacs.
+
+  The next time that same copy of Emacs starts up, it simply loads the
+preloaded Lisp files contained in that dump file, greatly improving
+start up time.
+
+  However, if by some unforseen circumstance the dump file is
+corrupted, Emacs can crash.  If that happens, the dump file stored in
+the Emacs files directory can be erased through the same preferences
+screen.
 
 @node Android File System
 @section What files Emacs can access under Android

java/Makefile.in

@@ -148,8 +148,7 @@ emacs.apk-in: $(CROSS_BINS) $(CROSS_LIBS) $(libsrc)/asset-directory-tool \
 	    cp -f $$file install_temp/lib/$(ANDROID_ABI);	\
 	  fi 							\
 	done
-	$(foreach module,$(NDK_BUILD_SHARED), \
+	cp -f $(NDK_BUILD_SHARED) install_temp/lib/$(ANDROID_ABI)
-	  cp -f $(module) install_temp/lib/$(ANDROID_ABI))
 # Package everything.  Specifying the assets on this command line is
 # necessary for AAssetManager_getNextFileName to work on old versions
 # of Android.

java/README

@@ -1,5 +1,11 @@
 This directory holds the Java sources of the port of GNU Emacs to
-Android-like systems.
+Android-like systems, along with files needed to create an application
+package out of them.
+
+`emacs.keystore' is the signing key used to build Emacs.  It is kept
+here, and we encourage all people redistributing Emacs to use this
+key.  It holds no security value, and otherwise it will be impossible
+to install different builds of Emacs on top of each other.
 
 Please keep the Java code indented with tabs and formatted according
 to the rules for C code in the GNU coding standards.  Always use

java/org/gnu/emacs/EmacsApplication.java

@@ -19,9 +19,59 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 
 package org.gnu.emacs;
 
-import android.app.Application;
+import java.io.File;
+import java.io.FileFilter;
 
-public class EmacsApplication extends Application
+import android.app.Application;
+import android.util.Log;
+
+public class EmacsApplication extends Application implements FileFilter
 {
-  /* This class currently does nothing.  */
+  private static final String TAG = "EmacsApplication";
+
+  /* The name of the dump file to use.  */
+  public static String dumpFileName;
+
+  @Override
+  public boolean
+  accept (File file)
+  {
+    return (!file.isDirectory ()
+	    && file.getName ().endsWith (".pdmp"));
+  }
+
+  @Override
+  public void
+  onCreate ()
+  {
+    File filesDirectory;
+    File[] allFiles;
+    String wantedDumpFile;
+    int i;
+
+    wantedDumpFile = ("emacs-" + EmacsNative.getFingerprint ()
+		      + ".pdmp");
+
+    Log.d (TAG, "onCreate: looking for " + wantedDumpFile);
+
+    /* Obtain a list of all files ending with ``.pdmp''.  Then, look
+       for a file named ``emacs-<fingerprint>.pdmp'' and delete the
+       rest.  */
+    filesDirectory = getFilesDir ();
+    allFiles = filesDirectory.listFiles (this);
+
+    /* Now try to find the right dump file.  */
+    for (i = 0; i < allFiles.length; ++i)
+      {
+	if (allFiles[i].getName ().equals (wantedDumpFile))
+	  dumpFileName = allFiles[i].getAbsolutePath ();
+	else
+	  /* Delete this outdated dump file.  */
+	  allFiles[i].delete ();
+      }
+
+    Log.d (TAG, "onCreate: found " + dumpFileName);
+
+    super.onCreate ();
+  }
 };

java/org/gnu/emacs/EmacsNative.java

@@ -25,6 +25,10 @@ import android.content.res.AssetManager;
 
 public class EmacsNative
 {
+  /* Obtain the fingerprint of this build of Emacs.  The fingerprint
+     can be used to determine the dump file name.  */
+  public static native String getFingerprint ();
+
   /* Set certain parameters before initializing Emacs.  This proves
      that libemacs.so is being loaded from Java code.
 

java/org/gnu/emacs/EmacsPreferencesActivity.java

@@ -19,6 +19,8 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 
 package org.gnu.emacs;
 
+import java.io.File;
+
 import android.app.Activity;
 import android.content.Intent;
 import android.os.Bundle;
@@ -93,6 +95,31 @@ public class EmacsPreferencesActivity extends Activity
       });
     layout.addView (textView);
 
+    textView = new TextView (this);
+    textView.setPadding (8, 20, 20, 8);
+
+    params = new LinearLayout.LayoutParams (LayoutParams.MATCH_PARENT,
+					    LayoutParams.WRAP_CONTENT);
+    textView.setLayoutParams (params);
+    textView.setText ("Erase dump file");
+    textView.setOnClickListener (new View.OnClickListener () {
+	@Override
+	public void
+	onClick (View view)
+	{
+	  String wantedDumpFile;
+	  File file;
+
+	  wantedDumpFile = ("emacs-" + EmacsNative.getFingerprint ()
+			    + ".pdmp");
+	  file = new File (getFilesDir (), wantedDumpFile);
+
+	  if (file.exists ())
+	    file.delete ();
+	}
+      });
+    layout.addView (textView);
+
     super.onCreate (savedInstanceState);
   }
 };

java/org/gnu/emacs/EmacsService.java

@@ -43,6 +43,8 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.res.AssetManager;
 
+import android.net.Uri;
+
 import android.os.Build;
 import android.os.Looper;
 import android.os.IBinder;
@@ -504,4 +506,27 @@ public class EmacsService extends Service
 						      EmacsService.class));
       }
   }
+
+  /* Ask the system to open the specified URL.
+     Value is NULL upon success, or a string describing the error
+     upon failure.  */
+
+  public String
+  browseUrl (String url)
+  {
+    Intent intent;
+
+    try
+      {
+	intent = new Intent (Intent.ACTION_VIEW, Uri.parse (url));
+	intent.setFlags (Intent.FLAG_ACTIVITY_NEW_TASK);
+	startActivity (intent);
+      }
+    catch (Exception e)
+      {
+	return e.toString ();
+      }
+
+    return null;
+  }
 };

java/org/gnu/emacs/EmacsThread.java

@@ -38,10 +38,23 @@ public class EmacsThread extends Thread
   {
     String args[];
 
+    if (EmacsApplication.dumpFileName == null)
+      {
 	if (!startDashQ)
 	  args = new String[] { "libandroid-emacs.so", };
 	else
 	  args = new String[] { "libandroid-emacs.so", "-Q", };
+      }
+    else
+      {
+	if (!startDashQ)
+	  args = new String[] { "libandroid-emacs.so", "--dump-file",
+	                        EmacsApplication.dumpFileName, };
+	else
+	  args = new String[] { "libandroid-emacs.so", "-Q",
+				"--dump-file",
+				EmacsApplication.dumpFileName, };
+      }
 
     /* Run the native code now.  */
     EmacsNative.initEmacs (args);

lisp/loadup.el

@@ -550,6 +550,32 @@ lost after dumping")))
 
 
 
+(if (eq system-type 'android)
+    (progn
+      ;; Dumping Emacs on Android works slightly differently from
+      ;; everywhere else.  The first time Emacs starts, Emacs dumps
+      ;; itself to "emacs-%s.pdump", and then proceeds with loadup,
+      ;; where %s is replaced by the dump fingerprint.
+      ;; EmacsApplication.java removes any pdump files with a
+      ;; different build fingerprint upon being created, which happens
+      ;; the moment the Android system starts Emacs.  Then, it passes
+      ;; the appropriate "--dump-file" to libemacs.so as it starts.
+      (let ((temp-dir (getenv "TEMP"))
+            (dump-file-name (format "%semacs-%s.pdmp"
+                                    (file-name-as-directory "~")
+                                    pdumper-fingerprint))
+            (dump-temp-file-name (format "%s~emacs-%s.pdmp"
+                                         (file-name-as-directory "~")
+                                         pdumper-fingerprint)))
+        (unless (pdumper-stats)
+          (condition-case ()
+              (progn
+                (dump-emacs-portable dump-temp-file-name)
+                ;; Move the dumped file to the actual dump file name.
+                (rename-file dump-temp-file-name dump-file-name)
+                ;; Continue with loadup.
+                nil)
+            (error nil)))))
   (if dump-mode
       (let ((output (cond ((equal dump-mode "pdump") "emacs.pdmp")
                           ((equal dump-mode "dump") "emacs")
@@ -585,6 +611,10 @@ lost after dumping")))
         ;; Recompute NAME now, so that it isn't set when we dump.
         (if (not (or (eq system-type 'ms-dos)
                      (eq system-type 'haiku) ;; BFS doesn't support hard links
+                     ;; There's no point keeping old dumps around for
+                     ;; the binary used to build Lisp on the build
+                     ;; machine.
+                     (featurep 'android)
                      ;; Don't bother adding another name if we're just
                      ;; building bootstrap-emacs.
                      (member dump-mode '("pbootstrap" "bootstrap"))))
@@ -609,7 +639,7 @@ lost after dumping")))
                                   (expand-file-name (concat name ".pdmp")
                                                     invocation-directory)
                                   t))))
-      (kill-emacs)))
+        (kill-emacs))))
 
 ;; This file must be loaded each time Emacs is run from scratch, e.g., temacs.
 ;; So run the startup code now.  First, remove `-l loadup' from args.

lisp/net/browse-url.el

@@ -52,6 +52,7 @@
 ;; browse-url-xdg-open                freedesktop.org xdg-open
 ;; browse-url-kde                     KDE konqueror (kfm)
 ;; browse-url-elinks                  Elinks      Don't know (tried with 0.12.GIT)
+;; browse-url-default-android-browser Android     2.3.3 (should work on 2.2 too)
 ;; eww-browse-url                     Emacs Web Wowser
 
 ;; Browsers can cache web pages so it may be necessary to tell them to
@@ -173,6 +174,9 @@
     ,@(when (eq system-type 'darwin)
         (list '(function-item :tag "Default macOS browser"
                               :value browse-url-default-macosx-browser)))
+    ,@(when (eq system-type 'android)
+        (list '(function-item :tag "Default Android browser"
+                              :value browse-url-default-android-browser)))
     (function-item :tag "Default browser"
 		   :value browse-url-default-browser)
     (function :tag "Your own function")
@@ -1057,6 +1061,8 @@ instead of `browse-url-new-window-flag'."
      'browse-url-default-macosx-browser)
     ((featurep 'haiku)
      'browse-url-default-haiku-browser)
+    ((eq system-type 'android)
+     'browse-url-default-android-browser)
     ((browse-url-can-use-xdg-open) 'browse-url-xdg-open)
 ;;;    ((executable-find browse-url-gnome-moz-program) 'browse-url-gnome-moz)
     ((executable-find browse-url-firefox-program) 'browse-url-firefox)
@@ -1294,6 +1300,22 @@ Default to the URL around or before point."
 (function-put 'browse-url-default-haiku-browser
               'browse-url-browser-kind 'external)
 
+(declare-function android-browse-url "androidselect.c")
+
+;;;###autoload
+(defun browse-url-default-android-browser (url &optional _new-window)
+  "Browse URL with the system default browser.
+Default to the URL around or before point."
+  (interactive (browse-url-interactive-arg "URL: "))
+  (setq url (browse-url-encode-url url))
+  ;; Make sure the URL starts with an appropriate scheme.
+  (unless (string-match "\\(.+\\):/" url)
+    (setq url (concat "http://" url)))
+  (android-browse-url url))
+
+(function-put 'browse-url-default-android-browser
+              'browse-url-browser-kind 'external)
+
 ;;;###autoload
 (defun browse-url-emacs (url &optional same-window)
   "Ask Emacs to load URL into a buffer and show it in another window.

m4/ndk-build.m4

@@ -67,7 +67,7 @@ esac
 # This is a map between pkg-config style package names and Android
 # ones.
 
-ndk_package_map="libwebpdemux:webpdemux libxml-2.0:libxml2"
+ndk_package_map="libwebpdemux:webpdemux libxml-2.0:libxml2 jansson:libjansson"
 
 # Replace ndk_module with the appropriate Android module name if it is
 # found in ndk_package_map.

src/android.c

@@ -33,6 +33,7 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 #include <sys/param.h>
 
 #include <assert.h>
+#include <fingerprint.h>
 
 #include "android.h"
 #include "androidgui.h"
@@ -95,6 +96,7 @@ struct android_emacs_service
   jmethodID detect_mouse;
   jmethodID name_keysym;
   jmethodID sync;
+  jmethodID browse_url;
 };
 
 struct android_emacs_pixmap
@@ -1294,6 +1296,18 @@ android_get_home_directory (void)
 #pragma GCC diagnostic ignored "-Wmissing-prototypes"
 #endif
 
+JNIEXPORT jstring JNICALL
+NATIVE_NAME (getFingerprint) (JNIEnv *env, jobject object)
+{
+  char buffer[sizeof fingerprint * 2 + 1];
+
+  memset (buffer, 0, sizeof buffer);
+  hexbuf_digest (buffer, (char *) fingerprint,
+		 sizeof fingerprint);
+
+  return (*env)->NewStringUTF (env, buffer);
+}
+
 JNIEXPORT void JNICALL
 NATIVE_NAME (setEmacsParams) (JNIEnv *env, jobject object,
 			      jobject local_asset_manager,
@@ -1514,6 +1528,8 @@ android_init_emacs_service (void)
   FIND_METHOD (detect_mouse, "detectMouse", "()Z");
   FIND_METHOD (name_keysym, "nameKeysym", "(I)Ljava/lang/String;");
   FIND_METHOD (sync, "sync", "()V");
+  FIND_METHOD (browse_url, "browseUrl", "(Ljava/lang/String;)"
+	       "Ljava/lang/String;");
 #undef FIND_METHOD
 }
 
@@ -4735,6 +4751,51 @@ android_project_image_nearest (struct android_image *image,
 
 
 
+/* Other miscellaneous functions.  */
+
+/* Ask the system to start browsing the specified encoded URL.  Upon
+   failure, return a string describing the error.  Else, value is
+   nil.  */
+
+Lisp_Object
+android_browse_url (Lisp_Object url)
+{
+  jobject value, string;
+  Lisp_Object tem;
+  const char *buffer;
+
+  string = android_build_string (url);
+  value = (*android_java_env)->CallObjectMethod (android_java_env,
+						 emacs_service,
+						 service_class.browse_url,
+						 string);
+  android_exception_check ();
+
+  ANDROID_DELETE_LOCAL_REF (string);
+
+  /* If no string was returned, return Qnil.  */
+  if (!value)
+    return Qnil;
+
+  buffer = (*android_java_env)->GetStringUTFChars (android_java_env,
+						   (jstring) value,
+						   NULL);
+  android_exception_check ();
+
+  /* Otherwise, build the string describing the error.  */
+  tem = build_string_from_utf8 (buffer);
+
+  (*android_java_env)->ReleaseStringUTFChars (android_java_env,
+					      (jstring) value,
+					      buffer);
+
+  /* And return it.  */
+  ANDROID_DELETE_LOCAL_REF (value);
+  return tem;
+}
+
+
+
 #else /* ANDROID_STUBIFY */
 
 /* X emulation functions for Android.  */

src/android.h

@@ -107,6 +107,10 @@ extern void android_closedir (struct android_dir *);
 
 
 
+/* Very miscellaneous functions.  */
+
+extern Lisp_Object android_browse_url (Lisp_Object);
+
 #endif
 
 /* JNI functions should not be built when Emacs is stubbed out for the

src/androidselect.c

@@ -213,6 +213,25 @@ DEFUN ("android-clipboard-exists-p", Fandroid_clipboard_exists_p,
   return rc ? Qt : Qnil;
 }
 
+DEFUN ("android-browse-url", Fandroid_browse_url,
+       Sandroid_browse_url, 1, 1, 0,
+       doc: /* Start the system web browser.
+Then, point the web browser to URL, which should be a URL-encoded
+URL with a scheme specified.  Signal an error upon failure.  */)
+  (Lisp_Object url)
+{
+  Lisp_Object value;
+
+  CHECK_STRING (url);
+  value = android_browse_url (url);
+
+  /* Signal an error upon failure.  */
+  if (!NILP (value))
+    signal_error ("Error browsing URL", value);
+
+  return Qnil;
+}
+
 
 
 void
@@ -246,4 +265,5 @@ syms_of_androidselect (void)
   defsubr (&Sandroid_set_clipboard);
   defsubr (&Sandroid_get_clipboard);
   defsubr (&Sandroid_clipboard_exists_p);
+  defsubr (&Sandroid_browse_url);
 }

src/emacs.c

@@ -744,6 +744,8 @@ argmatch (char **argv, int argc, const char *sstr, const char *lstr,
     }
 }
 
+#if !defined HAVE_ANDROID || defined ANDROID_STUBIFY
+
 /* Find a name (absolute or relative) of the Emacs executable whose
    name (as passed into this program) is ARGV0.  Called early in
    initialization by portable dumper loading code, so avoid Lisp and
@@ -843,6 +845,8 @@ find_emacs_executable (char const *argv0, ptrdiff_t *candidate_size)
 #endif	/* !WINDOWSNT */
 }
 
+#endif
+
 #ifdef HAVE_PDUMPER
 
 static const char *
@@ -875,6 +879,30 @@ dump_error_to_string (int result)
 static char *
 load_pdump (int argc, char **argv)
 {
+#if defined HAVE_ANDROID && !defined ANDROID_STUBIFY
+  char *dump_file = NULL;
+  int skip_args = 0, result;
+
+  while (skip_args < argc - 1)
+    {
+      if (argmatch (argv, argc, "-dump-file", "--dump-file", 6,
+		    &dump_file, &skip_args)
+	  || argmatch (argv, argc, "--", NULL, 2, NULL, &skip_args))
+	break;
+      skip_args++;
+    }
+
+  if (!dump_file)
+    return argv[0];
+
+  result = pdumper_load (dump_file, argv[0]);
+
+  if (result != PDUMPER_LOAD_SUCCESS)
+    fatal ("could not load dump file \"%s\": %s",
+	   dump_file, dump_error_to_string (result));
+  return argv[0];
+#else
+
   const char *const suffix = ".pdmp";
   int result;
   char *emacs_executable = argv[0];
@@ -1067,6 +1095,7 @@ load_pdump (int argc, char **argv)
   xfree (dump_file);
 
   return emacs_executable;
+#endif
 }
 #endif /* HAVE_PDUMPER */
 

src/pdumper.c

@@ -4072,10 +4072,12 @@ types.  */)
 {
   eassert (initialized);
 
+#ifndef HAVE_ANDROID
   if (! noninteractive)
     error ("Dumping Emacs currently works only in batch mode.  "
            "If you'd like it to work interactively, please consider "
            "contributing a patch to Emacs.");
+#endif
 
   if (will_dump_with_unexec_p ())
     error ("This Emacs instance was started under the assumption "
@@ -5842,6 +5844,10 @@ void
 syms_of_pdumper (void)
 {
 #ifdef HAVE_PDUMPER
+  unsigned char desired[sizeof fingerprint];
+  int i;
+  char hexbuf[2 * sizeof fingerprint];
+
   defsubr (&Sdump_emacs_portable);
   defsubr (&Sdump_emacs_portable__sort_predicate);
   defsubr (&Sdump_emacs_portable__sort_predicate_copied);
@@ -5854,5 +5860,17 @@ syms_of_pdumper (void)
   DEFSYM (Qdump_file_name, "dump-file-name");
   DEFSYM (Qafter_pdump_load_hook, "after-pdump-load-hook");
   defsubr (&Spdumper_stats);
+
+  for (i = 0; i < sizeof fingerprint; i++)
+    desired[i] = fingerprint[i];
+
+  hexbuf_digest (hexbuf, desired, sizeof desired);
+
+  DEFVAR_LISP ("pdumper-fingerprint", Vpdumper_fingerprint,
+	       doc: /* The fingerprint of this Emacs binary.
+It is a string that is supposed to be unique to each build of
+Emacs.  */);
+  Vpdumper_fingerprint = make_unibyte_string ((char *) hexbuf,
+					      sizeof hexbuf);
 #endif /* HAVE_PDUMPER */
 }

src/sfntfont-android.c

@@ -320,7 +320,10 @@ sfntfont_android_composite_bitmap (unsigned char *restrict buffer,
 {
   unsigned int *src_row;
   unsigned int *dst_row;
-  unsigned int i, src_y, x, src_x, max_x, dst_x, lim_x;
+  unsigned int i, src_y, x, src_x, max_x, dst_x;
+#ifdef __aarch64__
+  unsigned int lim_x;
+#endif
 
   if ((intptr_t) dest & 3 || bitmap_info->stride & 3)
     /* This shouldn't be possible as Android is supposed to align the
@@ -353,10 +356,10 @@ sfntfont_android_composite_bitmap (unsigned char *restrict buffer,
 	      src_x = x + (rect->x - text_rectangle->x);
 	      dst_x = x + rect->x;
 
+#ifdef __aarch64__
 	      /* This is the largest value of src_x.  */
 	      lim_x = max_x + (rect->x - text_rectangle->x);
 
-#ifdef __aarch64__
 	      if (!sfntfont_android_over_8888 (src_row + src_x,
 					       dst_row + dst_x,
 					       src_row + lim_x,