Update Android port

* src/android.c (android_run_select_thread, android_init_events) (android_select): Add alternative android_select implementation for API 16 and lower. * src/androidterm.c (handle_one_android_event): Fix use-after-frees.
2023-01-20 21:21:15 +08:00 · 2023-01-20 21:21:15 +08:00 · 26f0dd5089
commit 26f0dd5089
parent 01ee2bd07b
25 changed files with 172 additions and 70 deletions
--- a/admin/merge-gnulib
+++ b/admin/merge-gnulib
@ -140,8 +140,9 @@ cp -- "$gnulib_srcdir"/lib/af_alg.h \
 { test -z "$src" || cd "$src"; } &&
 ./autogen.sh

-# Finally, update the files in lib/ to xcompile/lib.
-rsync -r "$src"/lib "$src"/xcompile
+# Finally, copy gnulib stuff in lib/ to xcompile/lib.
+rm -rf "$src"xcompile/lib
+cp -r "$src"lib "$src"xcompile

 # Remove unnecessary files.
-rm -f "$src"/xcompile/lib/*.mk.in "$src"/xcompile/lib/Makefile.in
+rm -f "$src"xcompile/lib/*.mk.in "$src"xcompile/lib/Makefile.in
--- a/lib/_Noreturn.h
+++ b/lib/_Noreturn.h
@ -26,6 +26,11 @@
       AIX system header files and several gnulib header files use precisely
       this syntax with 'extern'.  */
 #  define _Noreturn [[noreturn]]
+# elif (defined __clang__ && __clang_major__ < 16 \
+        && defined _GL_WORK_AROUND_LLVM_BUG_59792)
+   /* Compile with -D_GL_WORK_AROUND_LLVM_BUG_59792 to work around
+      that rare LLVM bug, though you may get many false-alarm warnings.  */
+#  define _Noreturn
 # elif ((!defined __cplusplus || defined __clang__) \
        && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) \
            || (!defined __STRICT_ANSI__ \
--- a/lib/gnulib.mk.in
+++ b/lib/gnulib.mk.in
@ -186,6 +186,7 @@ ANDROID_JAR = @ANDROID_JAR@
 ANDROID_LIBS = @ANDROID_LIBS@
 ANDROID_MIN_SDK = @ANDROID_MIN_SDK@
 ANDROID_OBJ = @ANDROID_OBJ@
+ANDROID_SDK_18_OR_EARLIER = @ANDROID_SDK_18_OR_EARLIER@
 APPLE_UNIVERSAL_BUILD = @APPLE_UNIVERSAL_BUILD@
 AR = @AR@
 ARFLAGS = @ARFLAGS@
--- a/m4/canonicalize.m4
+++ b/m4/canonicalize.m4
@ -1,4 +1,4 @@
-# canonicalize.m4 serial 37
+# canonicalize.m4 serial 38

 dnl Copyright (C) 2003-2007, 2009-2023 Free Software Foundation, Inc.

@ -12,7 +12,8 @@ AC_DEFUN([gl_FUNC_CANONICALIZE_FILENAME_MODE],
 [
  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
  AC_REQUIRE([gl_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK])
-  AC_CHECK_FUNCS_ONCE([canonicalize_file_name faccessat])
+  AC_CHECK_FUNCS_ONCE([canonicalize_file_name])
+  gl_CHECK_FUNCS_ANDROID([faccessat], [[#include <unistd.h>]])
  AC_REQUIRE([gl_DOUBLE_SLASH_ROOT])
  AC_REQUIRE([gl_FUNC_REALPATH_WORKS])
  if test $ac_cv_func_canonicalize_file_name = no; then
@ -58,7 +59,8 @@ AC_DEFUN([gl_CANONICALIZE_LGPL_SEPARATE],
 [
  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
  AC_REQUIRE([gl_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK])
-  AC_CHECK_FUNCS_ONCE([canonicalize_file_name faccessat])
+  AC_CHECK_FUNCS_ONCE([canonicalize_file_name])
+  gl_CHECK_FUNCS_ANDROID([faccessat], [[#include <unistd.h>]])

  dnl On native Windows, we use _getcwd(), regardless whether getcwd() is
  dnl available through the linker option '-loldnames'.
--- a/m4/euidaccess.m4
+++ b/m4/euidaccess.m4
@ -1,4 +1,4 @@
-# euidaccess.m4 serial 16
+# euidaccess.m4 serial 17
 dnl Copyright (C) 2002-2023 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -32,7 +32,7 @@ AC_DEFUN([gl_FUNC_EUIDACCESS],
 # Prerequisites of lib/euidaccess.c.
 AC_DEFUN([gl_PREREQ_EUIDACCESS], [
  dnl Prefer POSIX faccessat over non-standard euidaccess.
-  AC_CHECK_FUNCS_ONCE([faccessat])
+  gl_CHECK_FUNCS_ANDROID([faccessat], [[#include <unistd.h>]])
  dnl Try various other non-standard fallbacks.
  AC_CHECK_HEADERS([libgen.h])
  AC_FUNC_GETGROUPS
--- a/m4/faccessat.m4
+++ b/m4/faccessat.m4
@ -1,4 +1,4 @@
-# serial 10
+# serial 11
 # See if we need to provide faccessat replacement.

 dnl Copyright (C) 2009-2023 Free Software Foundation, Inc.
@ -16,7 +16,7 @@ AC_DEFUN([gl_FUNC_FACCESSAT],
  dnl Persuade glibc <unistd.h> to declare faccessat().
  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])

-  AC_CHECK_FUNCS_ONCE([faccessat])
+  gl_CHECK_FUNCS_ANDROID([faccessat], [[#include <unistd.h>]])
  if test $ac_cv_func_faccessat = no; then
    HAVE_FACCESSAT=0
  else
--- a/m4/fchmodat.m4
+++ b/m4/fchmodat.m4
@ -1,4 +1,4 @@
-# fchmodat.m4 serial 7
+# fchmodat.m4 serial 8
 dnl Copyright (C) 2004-2023 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -97,6 +97,6 @@ AC_DEFUN([gl_FUNC_FCHMODAT],
 # Prerequisites of lib/fchmodat.c.
 AC_DEFUN([gl_PREREQ_FCHMODAT],
 [
-  AC_CHECK_FUNCS_ONCE([readlinkat])
+  gl_CHECK_FUNCS_ANDROID([readlinkat], [[#include <unistd.h>]])
  :
 ])
--- a/m4/futimens.m4
+++ b/m4/futimens.m4
@ -1,4 +1,4 @@
-# serial 9
+# serial 10
 # See if we need to provide futimens replacement.

 dnl Copyright (C) 2009-2023 Free Software Foundation, Inc.
@ -13,7 +13,7 @@ AC_DEFUN([gl_FUNC_FUTIMENS],
  AC_REQUIRE([gl_SYS_STAT_H_DEFAULTS])
  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
-  AC_CHECK_FUNCS_ONCE([futimens])
+  gl_CHECK_FUNCS_ANDROID([futimens], [[#include <sys/stat.h>]])
  if test $ac_cv_func_futimens = no; then
    HAVE_FUTIMENS=0
  else
--- a/m4/getdelim.m4
+++ b/m4/getdelim.m4
@ -1,4 +1,4 @@
-# getdelim.m4 serial 16
+# getdelim.m4 serial 17

 dnl Copyright (C) 2005-2007, 2009-2023 Free Software Foundation, Inc.
 dnl
@ -18,7 +18,7 @@ AC_DEFUN([gl_FUNC_GETDELIM],

  AC_CHECK_DECLS_ONCE([getdelim])

-  AC_CHECK_FUNCS_ONCE([getdelim])
+  gl_CHECK_FUNCS_ANDROID([getdelim], [[#include <stdio.h>]])
  if test $ac_cv_func_getdelim = yes; then
    HAVE_GETDELIM=1
    dnl Found it in some library.  Verify that it works.
--- a/m4/getline.m4
+++ b/m4/getline.m4
@ -1,4 +1,4 @@
-# getline.m4 serial 30
+# getline.m4 serial 31

 dnl Copyright (C) 1998-2003, 2005-2007, 2009-2023 Free Software Foundation,
 dnl Inc.
@ -23,12 +23,9 @@ AC_DEFUN([gl_FUNC_GETLINE],

  AC_CHECK_DECLS_ONCE([getline])

-  gl_getline_needs_run_time_check=no
-  AC_CHECK_FUNC([getline],
-                [dnl Found it in some library.  Verify that it works.
-                 gl_getline_needs_run_time_check=yes],
-                [am_cv_func_working_getline=no])
-  if test $gl_getline_needs_run_time_check = yes; then
+  gl_CHECK_FUNCS_ANDROID([getline], [[#include <stdio.h>]])
+  if test $ac_cv_func_getline = yes; then
+    dnl Found it in some library.  Verify that it works.
    AC_CACHE_CHECK([for working getline function],
      [am_cv_func_working_getline],
      [echo fooNbarN | tr -d '\012' | tr N '\012' > conftest.data
@ -85,6 +82,8 @@ AC_DEFUN([gl_FUNC_GETLINE],
            ])
         ])
      ])
+  else
+    am_cv_func_working_getline=no
  fi

  if test $ac_cv_have_decl_getline = no; then
--- a/m4/getloadavg.m4
+++ b/m4/getloadavg.m4
@ -7,7 +7,7 @@
 # gives unlimited permission to copy and/or distribute it,
 # with or without modifications, as long as this notice is preserved.

-#serial 10
+#serial 11

 # Autoconf defines AC_FUNC_GETLOADAVG, but that is obsolescent.
 # New applications should use gl_GETLOADAVG instead.
@ -25,8 +25,9 @@ gl_save_LIBS=$LIBS
 # getloadavg is present in libc on glibc >= 2.2, Mac OS X, FreeBSD >= 2.0,
 # NetBSD >= 0.9, OpenBSD >= 2.0, Solaris >= 7.
 HAVE_GETLOADAVG=1
-AC_CHECK_FUNC([getloadavg], [],
-  [gl_func_getloadavg_done=no
+gl_CHECK_FUNCS_ANDROID([getloadavg], [[#include <stdlib.h>]])
+if test $ac_cv_func_getloadavg != yes; then
+   gl_func_getloadavg_done=no

   # Some systems with -lutil have (and need) -lkvm as well, some do not.
   # On Solaris, -lkvm requires nlist from -lelf, so check that first
@ -73,7 +74,8 @@ AC_CHECK_FUNC([getloadavg], [],
          AC_DEFINE([DGUX], [1], [Define to 1 for DGUX with <sys/dg_sys_info.h>.])
          AC_CHECK_LIB([dgc], [dg_sys_info])])
     fi
-   fi])
+   fi
+fi

 if test "x$gl_save_LIBS" = x; then
  GETLOADAVG_LIBS=$LIBS
--- a/m4/gnulib-common.m4
+++ b/m4/gnulib-common.m4
@ -38,6 +38,11 @@ AC_DEFUN([gl_COMMON_BODY], [
       AIX system header files and several gnulib header files use precisely
       this syntax with 'extern'.  */
 #  define _Noreturn [[noreturn]]
+# elif (defined __clang__ && __clang_major__ < 16 \
+        && defined _GL_WORK_AROUND_LLVM_BUG_59792)
+   /* Compile with -D_GL_WORK_AROUND_LLVM_BUG_59792 to work around
+      that rare LLVM bug, though you may get many false-alarm warnings.  */
+#  define _Noreturn
 # elif ((!defined __cplusplus || defined __clang__) \
        && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) \
            || (!defined __STRICT_ANSI__ \
--- a/m4/gnulib-comp.m4
+++ b/m4/gnulib-comp.m4
@ -28,7 +28,7 @@
 # other built files.


-# This macro should be invoked from ./configure.ac, in the section
+# This macro should be invoked from .//configure.ac, in the section
 # "Checks for programs", right after AC_PROG_CC, and certainly before
 # any checks for libraries, header files, types and library functions.
 AC_DEFUN([gl_EARLY],
@ -214,7 +214,7 @@ AC_DEFUN([gl_EARLY],
  # Code from module xalloc-oversized:
 ])

-# This macro should be invoked from ./configure.ac, in the section
+# This macro should be invoked from .//configure.ac, in the section
 # "Check for header files, types and library functions".
 AC_DEFUN([gl_INIT],
 [
@ -252,7 +252,7 @@ AC_DEFUN([gl_INIT],
  gl_STDLIB_MODULE_INDICATOR([canonicalize_file_name])
  gl_STDLIB_MODULE_INDICATOR([realpath])
  AC_REQUIRE([AC_C_RESTRICT])
-  AC_CHECK_FUNCS_ONCE([readlinkat])
+  gl_CHECK_FUNCS_ANDROID([readlinkat], [[#include <unistd.h>]])
  gl_CLOCK_TIME
  gl_MODULE_INDICATOR([close-stream])
  gl_FUNC_COPY_FILE_RANGE
--- a/m4/mempcpy.m4
+++ b/m4/mempcpy.m4
@ -1,4 +1,4 @@
-# mempcpy.m4 serial 12
+# mempcpy.m4 serial 13
 dnl Copyright (C) 2003-2004, 2006-2007, 2009-2023 Free Software Foundation,
 dnl Inc.
 dnl This file is free software; the Free Software Foundation
@ -14,7 +14,7 @@ AC_DEFUN([gl_FUNC_MEMPCPY],
  AC_REQUIRE([AC_C_RESTRICT])

  AC_REQUIRE([gl_STRING_H_DEFAULTS])
-  AC_CHECK_FUNCS([mempcpy])
+  gl_CHECK_FUNCS_ANDROID([mempcpy], [[#include <string.h>]])
  if test $ac_cv_func_mempcpy = no; then
    HAVE_MEMPCPY=0
  fi
--- a/m4/mkostemp.m4
+++ b/m4/mkostemp.m4
@ -1,4 +1,4 @@
-# mkostemp.m4 serial 2
+# mkostemp.m4 serial 3
 dnl Copyright (C) 2009-2023 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -11,7 +11,7 @@ AC_DEFUN([gl_FUNC_MKOSTEMP],
  dnl Persuade glibc <stdlib.h> to declare mkostemp().
  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])

-  AC_CHECK_FUNCS_ONCE([mkostemp])
+  gl_CHECK_FUNCS_ANDROID([mkostemp], [[#include <stdlib.h>]])
  if test $ac_cv_func_mkostemp != yes; then
    HAVE_MKOSTEMP=0
  fi
--- a/m4/nproc.m4
+++ b/m4/nproc.m4
@ -1,4 +1,4 @@
-# nproc.m4 serial 5
+# nproc.m4 serial 6
 dnl Copyright (C) 2009-2023 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -25,8 +25,8 @@ AC_DEFUN([gl_PREREQ_NPROC],
     #endif
    ])

-  AC_CHECK_FUNCS([sched_getaffinity sched_getaffinity_np \
-                  pstat_getdynamic sysmp sysctl])
+  AC_CHECK_FUNCS([sched_getaffinity_np pstat_getdynamic sysmp sysctl])
+  gl_CHECK_FUNCS_ANDROID([sched_getaffinity], [[#include <sched.h>]])

  dnl Test whether sched_getaffinity has the expected declaration.
  dnl glibc 2.3.[0-2]:
--- a/m4/pipe2.m4
+++ b/m4/pipe2.m4
@ -1,4 +1,4 @@
-# pipe2.m4 serial 2
+# pipe2.m4 serial 3
 dnl Copyright (C) 2009-2023 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -11,7 +11,7 @@ AC_DEFUN([gl_FUNC_PIPE2],
  dnl Persuade glibc <unistd.h> to declare pipe2().
  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])

-  AC_CHECK_FUNCS_ONCE([pipe2])
+  gl_CHECK_FUNCS_ANDROID([pipe2], [[#include <unistd.h>]])
  if test $ac_cv_func_pipe2 != yes; then
    HAVE_PIPE2=0
  fi
--- a/m4/readlinkat.m4
+++ b/m4/readlinkat.m4
@ -1,4 +1,4 @@
-# serial 6
+# serial 7
 # See if we need to provide readlinkat replacement.

 dnl Copyright (C) 2009-2023 Free Software Foundation, Inc.
@ -12,7 +12,7 @@ AC_DEFUN([gl_FUNC_READLINKAT],
 [
  AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
-  AC_CHECK_FUNCS_ONCE([readlinkat])
+  gl_CHECK_FUNCS_ANDROID([readlinkat], [[#include <unistd.h>]])
  AC_REQUIRE([gl_FUNC_READLINK])
  if test $ac_cv_func_readlinkat = no; then
    HAVE_READLINKAT=0
--- a/m4/stpcpy.m4
+++ b/m4/stpcpy.m4
@ -1,4 +1,4 @@
-# stpcpy.m4 serial 9
+# stpcpy.m4 serial 10
 dnl Copyright (C) 2002, 2007, 2009-2023 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -13,7 +13,7 @@ AC_DEFUN([gl_FUNC_STPCPY],
  AC_REQUIRE([AC_C_RESTRICT])

  AC_REQUIRE([gl_STRING_H_DEFAULTS])
-  AC_CHECK_FUNCS([stpcpy])
+  gl_CHECK_FUNCS_ANDROID([stpcpy], [[#include <string.h>]])
  if test $ac_cv_func_stpcpy = no; then
    HAVE_STPCPY=0
  fi
--- a/m4/timegm.m4
+++ b/m4/timegm.m4
@ -1,4 +1,4 @@
-# timegm.m4 serial 13
+# timegm.m4 serial 14
 dnl Copyright (C) 2003, 2007, 2009-2023 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@ -9,7 +9,7 @@ AC_DEFUN([gl_FUNC_TIMEGM],
  AC_REQUIRE([gl_TIME_H_DEFAULTS])
  AC_REQUIRE([gl_FUNC_MKTIME_WORKS])
  REPLACE_TIMEGM=0
-  AC_CHECK_FUNCS_ONCE([timegm])
+  gl_CHECK_FUNCS_ANDROID([timegm], [[#include <time.h>]])
  if test $ac_cv_func_timegm = yes; then
    if test "$gl_cv_func_working_mktime" != yes; then
      # Assume that timegm is buggy if mktime is.
--- a/m4/unistd_h.m4
+++ b/m4/unistd_h.m4
@ -50,7 +50,6 @@ AC_DEFUN_ONCE([gl_UNISTD_H],
    group_member isatty lchown link linkat lseek pipe pipe2 pread pwrite
    readlink readlinkat rmdir sethostname sleep symlink symlinkat
    truncate ttyname_r unlink unlinkat usleep])
-  gl_CHECK_FUNCS_ANDROID([ftruncate], [[#include <unistd.h>]])

  AC_REQUIRE([AC_C_RESTRICT])

--- a/m4/utimens.m4
+++ b/m4/utimens.m4
@ -3,7 +3,7 @@ dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.

-dnl serial 12
+dnl serial 15

 AC_DEFUN([gl_UTIMENS],
 [
@ -11,10 +11,11 @@ AC_DEFUN([gl_UTIMENS],
  AC_REQUIRE([gl_FUNC_UTIMES])
  AC_REQUIRE([gl_CHECK_TYPE_STRUCT_TIMESPEC])
  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
-  AC_CHECK_FUNCS_ONCE([futimens lutimes])
-  gl_CHECK_FUNCS_ANDROID([utimensat], [[#include <sys/stat.h>]])
  gl_CHECK_FUNCS_ANDROID([futimes], [[#include <sys/time.h>]])
  gl_CHECK_FUNCS_ANDROID([futimesat], [[#include <sys/time.h>]])
+  gl_CHECK_FUNCS_ANDROID([lutimes], [[#include <sys/time.h>]])
+  gl_CHECK_FUNCS_ANDROID([futimens], [[#include <sys/stat.h>]])
+  gl_CHECK_FUNCS_ANDROID([utimensat], [[#include <sys/stat.h>]])

  if test $ac_cv_func_futimens = no && test $ac_cv_func_futimesat = yes; then
    dnl FreeBSD 8.0-rc2 mishandles futimesat(fd,NULL,time).  It is not
--- a/m4/utimensat.m4
+++ b/m4/utimensat.m4
@ -1,4 +1,4 @@
-# serial 9
+# serial 10
 # See if we need to provide utimensat replacement.

 dnl Copyright (C) 2009-2023 Free Software Foundation, Inc.
@ -13,8 +13,6 @@ AC_DEFUN([gl_FUNC_UTIMENSAT],
  AC_REQUIRE([gl_SYS_STAT_H_DEFAULTS])
  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
-  # This is necessary for cross-compiles, because otherwise utimensat
-  # will appear to work.
  gl_CHECK_FUNCS_ANDROID([utimensat], [[#include <sys/stat.h>]])
  if test $ac_cv_func_utimensat = no; then
    HAVE_UTIMENSAT=0
--- a/src/android.c
+++ b/src/android.c
@ -257,30 +257,88 @@ static struct android_event_queue event_queue;
 /* Semaphores used to signal select completion and start.  */
 static sem_t android_pselect_sem, android_pselect_start_sem;

+#if __ANDROID_API__ < 16
+
+/* Select self-pipe.  */
+static int select_pipe[2];
+
+#endif
+
 static void *
 android_run_select_thread (void *data)
 {
+  int rc;
+#if __ANDROID_API__ < 16
+  int nfds;
+  fd_set readfds;
+  char byte;
+#else
  sigset_t signals, waitset;
-  int rc, sig;
-
-  sigfillset (&signals);
+#endif

 #if __ANDROID_API__ < 16
-  /* sigprocmask must be used instead of pthread_sigmask due to a bug
-     in Android versions earlier than 16.  It only affects the calling
-     thread on Android anyhow.  */
+  /* A completely different implementation is used when building for
+     Android versions earlier than 16, because pselect with a signal
+     mask does not work there.  Instead of blocking SIGUSR1 and
+     unblocking it inside pselect, a file descriptor is used instead.
+     Something is written to the file descriptor every time select is
+     supposed to return.  */

-  if (sigprocmask (SIG_BLOCK, &signals, NULL))
-    __android_log_print (ANDROID_LOG_FATAL, __func__,
-			 "sigprocmask: %s",
-			 strerror (errno));
+  while (true)
+    {
+      /* Wait for the thread to be released.  */
+      while (sem_wait (&android_pselect_start_sem) < 0)
+	;;
+
+      /* Get the select lock and call pselect.  API 8 does not have
+	 working pselect in any sense.  Instead, pselect wakes up on
+	 select_pipe[0].  */
+
+      pthread_mutex_lock (&event_queue.select_mutex);
+      nfds = android_pselect_nfds;
+      readfds = *android_pselect_readfds;
+
+      if (nfds < select_pipe[0] + 1)
+	nfds = select_pipe[0] + 1;
+      FD_SET (select_pipe[0], &readfds);
+
+      rc = pselect (nfds, &readfds,
+		    android_pselect_writefds,
+		    android_pselect_exceptfds,
+		    android_pselect_timeout,
+		    NULL);
+
+      /* Subtract 1 from rc if writefds contains the select pipe.  */
+      if (FD_ISSET (select_pipe[0],
+		    android_pselect_writefds))
+	rc -= 1;
+
+      android_pselect_rc = rc;
+      pthread_mutex_unlock (&event_queue.select_mutex);
+
+      /* Signal the main thread that there is now data to read.
+         It is ok to signal this condition variable without holding
+         the event queue lock, because android_select will always
+         wait for this to complete before returning.  */
+      android_pselect_completed = true;
+      pthread_cond_signal (&event_queue.read_var);
+
+      /* Read a single byte from the select pipe.  */
+      read (select_pipe[0], &byte, 1);
+
+
+      /* Signal the Emacs thread that pselect is done.  If read_var
+	 was signaled by android_write_event, event_queue.mutex could
+	 still be locked, so this must come before.  */
+      sem_post (&android_pselect_sem);
+    }
 #else
  if (pthread_sigmask (SIG_BLOCK, &signals, NULL))
    __android_log_print (ANDROID_LOG_FATAL, __func__,
 			 "pthread_sigmask: %s",
 			 strerror (errno));
-#endif

+  sigfillset (&signals);
  sigdelset (&signals, SIGUSR1);
  sigemptyset (&waitset);
  sigaddset (&waitset, SIGUSR1);
@ -321,10 +379,13 @@ android_run_select_thread (void *data)
 	 still be locked, so this must come before.  */
      sem_post (&android_pselect_sem);
    }
+#endif

  return NULL;
 }

+#if __ANDROID_API__ >= 16
+
 static void
 android_handle_sigusr1 (int sig, siginfo_t *siginfo, void *arg)
 {
@ -332,6 +393,8 @@ android_handle_sigusr1 (int sig, siginfo_t *siginfo, void *arg)
     sure the disposition of SIGUSR1 is enough.  */
 }

+#endif
+
 /* Set up the global event queue by initializing the mutex and two
   condition variables, and the linked list of events.  This must be
   called before starting the Emacs thread.  Also, initialize the
@ -366,12 +429,29 @@ android_init_events (void)
  event_queue.events.next = &event_queue.events;
  event_queue.events.last = &event_queue.events;

+#if __ANDROID_API__ >= 16
+
  /* Before starting the select thread, make sure the disposition for
     SIGUSR1 is correct.  */
  sigfillset (&sa.sa_mask);
  sa.sa_sigaction = android_handle_sigusr1;
  sa.sa_flags = SA_SIGINFO;

+#else
+
+  /* Set up the file descriptor used to wake up pselect.  */
+  if (pipe2 (select_pipe, O_CLOEXEC) < 0)
+    __android_log_print (ANDROID_LOG_FATAL, __func__,
+			 "pipe2: %s", strerror (errno));
+
+  /* Make sure the read end will fit in fd_set.  */
+  if (select_pipe[0] >= FD_SETSIZE)
+    __android_log_print (ANDROID_LOG_FATAL, __func__,
+			 "read end of select pipe"
+			 " lies outside FD_SETSIZE!");
+
+#endif
+
  if (sigaction (SIGUSR1, &sa, NULL))
    __android_log_print (ANDROID_LOG_FATAL, __func__,
 			 "sigaction: %s",
@ -479,6 +559,7 @@ android_select (int nfds, fd_set *readfds, fd_set *writefds,
 		fd_set *exceptfds, struct timespec *timeout)
 {
  int nfds_return;
+  static char byte;

  pthread_mutex_lock (&event_queue.mutex);

@ -505,9 +586,16 @@ android_select (int nfds, fd_set *readfds, fd_set *writefds,
  /* Start waiting for the event queue condition to be set.  */
  pthread_cond_wait (&event_queue.read_var, &event_queue.mutex);

+#if __ANDROID_API__ >= 16
  /* Interrupt the select thread now, in case it's still in
     pselect.  */
  pthread_kill (event_queue.select_thread, SIGUSR1);
+#else
+  /* Interrupt the select thread by writing to the select pipe.  */
+  if (write (select_pipe[1], &byte, 1) != 1)
+    __android_log_print (ANDROID_LOG_FATAL, __func__,
+			 "write: %s", strerror (errno));
+#endif

  /* Wait for pselect to return in any case.  */
  while (sem_wait (&android_pselect_sem) < 0)
@ -4425,8 +4513,6 @@ android_project_image_nearest (struct android_image *image,
 int
 android_ftruncate (int fd, off_t length)
 {
-  int rc;
-
 #if defined __arm__ || defined __mips__
  return syscall (SYS_ftruncate64, fd, 0,
 		  (unsigned int) (length & 0xffffffff),
--- a/src/androidterm.c
+++ b/src/androidterm.c
@ -966,6 +966,7 @@ handle_one_android_event (struct android_display_info *dpyinfo,
      touchpoint->x = event->touch.x;
      touchpoint->y = event->touch.x;
      touchpoint->next = FRAME_OUTPUT_DATA (any)->touch_points;
+      touchpoint->tool_bar_p = false;
      FRAME_OUTPUT_DATA (any)->touch_points = touchpoint;

      /* Figure out whether or not the tool was pressed on the tool
@ -1072,13 +1073,10 @@ handle_one_android_event (struct android_display_info *dpyinfo,
 	    {
 	      *last = touchpoint->next;

-	      /* The tool was unlinked.  Free it and generate the
-		 appropriate Emacs event (assuming that it was not
-		 grabbed by the tool bar).  */
-	      xfree (touchpoint);
-
 	      if (touchpoint->tool_bar_p)
 		{
+		  xfree (touchpoint);
+
 		  /* Do what is necessary to release the tool bar and
 		     possibly trigger a click.  */

@ -1094,6 +1092,11 @@ handle_one_android_event (struct android_display_info *dpyinfo,
 		  goto OTHER;
 		}

+	      /* The tool was unlinked.  Free it and generate the
+		 appropriate Emacs event (assuming that it was not
+		 grabbed by the tool bar).  */
+	      xfree (touchpoint);
+
 	      inev.ie.kind = TOUCHSCREEN_END_EVENT;
 	      inev.ie.timestamp = event->touch.time;