Introduce an Android window system port for GNU Emacs

* src/xterm.h: New fields `quit_keysym' and `quit_keysym_time'.
* src/xterm.c (handle_one_xevent): Check for the quit keysym, and
set Vquit_flag upon witnessing two clicks in rapid succession.
(x_term_init): Set `quit_keysym'.
(init_xterm): Fix typo in name of `register_textconv_interface'.
(syms_of_xterm) <Vx_toolkit_scroll_bars>: Describe its default
value on android.

* src/xfns.c (xic_string_conversion_callback): Pass `0' as the
last argument to textconv_query.
(Fx_server_vendor, Fx_server_version): Document return values on
Android.

* src/xfaces.c (Fx_family_fonts, set_lface_from_font): Use
FRAME_RES instead of FRAME_RES_Y, respecting user preferences on
window systems that have distinct display and font scaling
factors.
(Fx_load_color_file): Call `emacs_fclose', not fclose.

* src/xdisp.c (tab_bar_item_info): Allow `close_p' to be NULL.
(get_tab_bar_item): Update commentary to reflect that change.
(get_tab_bar_item_kbd): New function, resembling get_tab_bar_item.
(build_desired_tool_bar_string): Clear `f->tool_bar_wraps_p';
insert new line characters if a QCwrap item is encountered, and
set f->tool_bar_wrap_p.  Replace characters beyond the end of the
tool bar with spaces.
(display_tool_bar_line): Move iterator to the next line if in
contact with an explicit line-wrap item.
(redisplay_internal): If there are newline characters in the tool
bar, refrain from coercing each row into being identically tall.
Don't call `set_tty_color_mode' on Android.
(mark_window_display_accurate_1): Report changes to the point and
mark to input methods.
(display_menu_bar): Adjust ifdefs to allow non-X window systems to
use the built-in menu bar.
(draw_row_with_mouse_face): Don't call TTY functions on Android.
(note_mouse_highlight): Call `popup_activated' on Android.
(expose_frame): Correctly work on the menu bar window.
(gui_union_rectangles): New function.

* src/window.h (struct window): New fields for recording the last
window and point positions, along with an ephemeral position used
during IM text conversion.
(WINDOW_MENU_BAR_P): Correct definition for non-X window systems
without external menu bars.

* src/window.c (replace_buffer_in_windows): Call
Qreplace_buffer_in_windows only when bound.

* src/w32proc.c (sys_spawnve): Pass extra argument to openp.

* src/w32font.c (fill_in_logfont): Use font scaling factor, not
the display scaling factor.

* src/w32.c (check_windows_init_file): Pass extra argument to
openp.

* src/verbose.mk.in (AM_V_JAVAC, AM_V_DX, AM_V_AAPT)
(AM_V_ZIPALIGN, AM_V_SILENT): New variables.

* src/textconv.h (struct textconv_interface): New `point_changed',
`compose_region_changed' and `notify_conversion'.
Add declarations for new functions.

* src/textconv.c (TEXTCONV_DEBUG): New macro.
(suppress_conversion_count): New variable.
(enum textconv_batch_edit_flags): New flag.
(copy_buffer): Don't overwrite text before the gap with the text
after.
(get_mark, select_window): New functions.
(textconv_query): New argument FLAGS.  Contingent upon its value,
use the previous point or mark or skip the conversion region.
(sync_overlay, record_buffer_change, reset_frame_state)
(detect_conversion_events, restore_selected_window)
(really_commit_text, really_finish_composing_text)
(really_set_composing_region, really_delete_composing_text)
(really_request_point_update, really_set_point_and_mark)
(complete_edit): New functions.
(struct complete_edit_check_context): New structure; store in it
the result of editing operations.
(complete_edit_check, handle_pending_conversion_events_1)
(decrement_inside, handle_pending_conversion_events)
(start_batch_edit, end_batch_edit, commit_text)
(set_composing_text, textconv_set_point_and_mark)
(request_point_update, textconv_barrier, get_extracted_text)
(get_surrounding_text, conversion_disabled_p)
(report_selected_window_change, report_point_change)
(disable_text_conversion, resume_text_conversion)
(register_textconv_interface, check_postponed_buffers)
(postponed_buffers, Fset_text_conversion_style)
(syms_of_textconv) <Qaction, Qtext_conversion, Qpush_mark,
Qunderline, Qoverriding_text_conversion_style,
Vtext_conversion_edits, Voverriding_text_conversion_style,
Vtext_conversion_face>: New functions, symbols and variables.

* src/terminal.c (Fterminal_live_p): Return Qandroid if type is
output_android.

* src/termhooks.h (enum output_method): Add `output_android'.
(struct terminal) <display_info>: Add union constituent field for
`android'.
<query_colors>: Define on Android as well.
(TERMINAL_FONT_CACHE) [HAVE_ANDROID]: Return the inappropriately
named font cache field on Android.

* src/term.c (string_cost, string_cost_one_line, per_line_cost)
(calculate_costs, produce_glyphs, produce_glyphs, tty_capable_p)
(tty_capable_p, device, init_tty, maybe_fatal)
(delete_tty) [HAVE_ANDROID]: Exclude or turn these functions into
vestiges.
(Fsuspend_tty, Fresume_tty): Call `emacs_fclose' and always signal
on Android.
(Fresume_tty): Call `emacs_fdopen'.
(Ftty__set_output_buffer_size) [HAVE_ANDROID]: Remove this
function.
(encode_terminal_code): Replace with a stub.
(init_tty, delete_tty, maybe_fatal): Call `emacs_fclose'.
(syms_of_term): Remove most unnecessary code on Android.
<system_uses_terminfo>: Always set this option on Android.

* src/sysdep.c (init_standard_fds): Call emacs_fopen.
(reset_sigio, widen_foreground_group): Define out on Android.
(reset_sys_modes): Don't call either function on Android.
(init_sigbus, handle_sigbus): New functions.
(init_signals): Don't add user signals on Android.  Register
signal handlers for SIGBUS, and refrain from handling SIGSEGV.
(emacs_fstatat): Wrap android_fstatat on Android.
(sys_fstat, sys_faccessat): New function.
(emacs_openat): Exclude this function when building libemacs.so.
(emacs_open, emacs_open_noquit, emacs_fopen, emacs_close): Wrap
functions defined in the Android filesystem emulation code.
(emacs_fdopen, emacs_fclose, emacs_unlink, emacs_symlink)
(emacs_rmdir, emacs_mkdir, emacs_renameat_noreplace, emacs_rename)
(emacs_fchmodat): New wrappers for more of those functions.
(close_output_streams): Placate the file descriptor sanitizer
that's included with android.

* src/sound.c (Fplay_sound_internal): Pass extra argument to openp.

* src/sfntfont.h:
* src/sfntfont.c:
* src/sfntfont-android.c:
* src/sfnt.h:
* src/sfnt.c: New files.
* src/scroll.c: Exclude the entire file on Android.

* src/process.c: (allocate_pty): Call sys_faccessat, not
faccessat.
(Fmake_process): Call openp with an extra argument.
(wait_reading_process_output): Call android_select.
(Fprocess_send_eof): Don't call tcdrain if not present.
(handle_child_signal): Write a comment describing a small, seldom
encountered issue.

* src/print.c (print_vectorlike): Don't print FONT_EXTRA_INDEX for
font entities.

* src/pdumper.c (Fdump_emacs_portable): Allow dumping in
interactive Emacs's on Android, as this is performed within
loadup.el.
(dump_discard_mem): Use madvise if posix_advise is not present.
(pdumper_load): Call sys_fstat, not fstat.
(syms_of_pdumper) <Vpdumper_fingerprint>: Calculate the
fingerprint for this Emacs executable and store it there.

* src/menu.c (have_boxes): Android has boxes.
(push_submenu_start, push_submenu_end): Define on Android.
(single_menu_item): Produce submenus on Android as well.
(x_popup_menu_1): Call EVENT_START, in contrast to duplicating its
old functionality with calls to Fcar and XCDR.
(Fx_popup_menu): Update documentation to reflect that touch screen
events are now accepted as POSITION.

* src/marker.c (set_marker_internal): Redisplay buffers when their
mark changes, enabling changes to be reported to the IME.

* src/lread.c (lread_fd, lread_fd_cmp, lread_fd_p, lread_close)
(lread_fstat, lread_read_quit, lread_lseek, file_stream)
(file_seek, file_stream_valid_p, file_stream_close)
(file_stream_invalid, getc): New macros.  Define to an
implementation with file descriptors and file streams on systems
other than Android 2.3+, and one using Android file descriptors on
those systems.
(USE_ANDROID_ASSETS): Define on Android 2.3+;
(file_get_char): New function.
(infile, skip_dyn_bytes, skip_dyn_eof, readbyte_from_stdio)
(read_filtered_event, safe_to_load_version, close_infile_unwind):
Implement in terms of those macros.
(close_file_unwind_android_fd): New function.
(Fload): Pass extra argument to `openp' and use Android file
descriptors where possible.
(Flocate_file_internal): Pass extra argument to `openp'.
(maybe_swap_for_eln1): Call sys_fstat, not fstat.
(openp): New arg PLATFORM; if supplied and opening a
platform-specific file descriptor replacement is possible, place
one there.
(build_load_history): Fix typos in comments.
(skip_lazy_string): Implement in terms of the aformentioned
macros.

* src/lisp.h: Add declarations for new functions.
* src/keyboard.h (reading_key_sequence): Declare here.
(EVENT_START): Treat touch screen events specially by returning
the posn of their touch point.

* src/keyboard.c (reading_key_sequence, menu_bar_touch_id): New
variables.
(command_loop_1):
(read_menu_command): Pass false to read_key_sequence.
(read_char): Update commentary.
(readable_events): If text conversion events (edits from an input
method) are queued, return 1.
(kbd_buffer_get_event): If text conversion events exist, carry out
the edits contained within.  Then, generate a Qtext_conversion
event.
(lispy_function_keys, FUNCTION_KEY_OFFSET): Define function key
array on Android.
(coords_in_tab_bar_window): New function.
(make_lispy_event) <TOUCHSCREEN_BEGIN_EVENT>: Keep track of
touches that fall into the confines of the tab bar, and include
the tab bar item in their position lists.  Moreover, retain and
track the touch in C code if it's taking place within the menu
bar.
<TOUCHSCREEN_END_EVENT>: Likewise for the tab bar; generate menu
bar events if the touch ends on a menu item and was previously
singled out for tracking.
<TOUCHSCREEN_UPDATE_EVENT>: Don't deliver this event if the frame
is dead, or if it was identified for tracking since the only touch
sequence that changed begun inside the menu bar.
(handle_async_input): Call android_check_query_urgent.
(handle_input_available_signal): Add memory fence.
(parse_tool_bar_item): Handle `wrap' properties within tool bar
items moving subsequent items onto a new row.
(access_keymap_keyremap): New arguments START, END, KEYBUF.
Set Qcurrent_key_remap_sequence around calls to the remap
function.
(keyremap_step): Pass the necessary information to
access_keymap_keyremap.
(restore_reading_key_sequence): New function.
(read_key_sequence): Set `reading_key_sequence'.  New arg
DISABLE_TEXT_CONVERSION_P, which causes text conversion to be
disabled as long as the key sequence is being read.  Disable text
conversion as well if a menu or function key prefix is read,
insert imaginary prefix keys before touchscreen events within
special areas of a frame.  Don't insert prefix keys if input is
being mocked, which transpires if the input is in actuality
originating from a key translation map.
(read_key_sequence_vs): New argument DISABLE_TEXT_CONVERSION.
(Fread_key_sequence): New argument DISABLE_TEXT_CONVERSION.
(Fopen_dribble_file): Use emacs_fclose.
(head_table): Make touchscreen-begin and touchscreen-end events
touchscreen events.
(syms_of_keyboard) <QCwrap, Qtouchscreen, Qtext_conversion>: New
symbols.
<disable_inhibit_text_conversion, Vcurrent_key_remap_sequence>:
New variables.

* src/inotify.c (Finotify_add_watch): Detect and avoid watching
special files that don't exist from the POV of inotify.

* src/image.c (image_create_bitmap_from_data)
(image_create_bitmap_from_file, free_bitmap_record)
(prepare_image_for_display, image_clear_image_1)
(image_clear_image_1, image_size_in_bytes, image_set_transform):
(Create_Pixmap_From_Bitmap_Data, lookup_rgb_color)
(image_to_emacs_colors, image_from_emacs_colors)
(image_pixmap_draw_cross, image_disable_image): Implement on
Android, reusing much of the X11 code.
(matrix_identity, matrix_rotate, matrix_mirror_horizontal)
(matrix_translate): New functions.
(x_check_image_size, x_create_x_image_and_pixmap)
(x_destroy_x_image, image_check_image_size)
(image_create_x_image_and_pixmap_1, image_destroy_x_image)
(gui_put_x_image, image_get_x_image, image_unget_x_image):
Implement on Android.
(image_find_image_fd): Return an Android file descriptor if
possible.
(close_android_fd): New function.
(slurp_file): Accept `image_fds', defined to Android file
descriptors.
(xpm_load): Enable built-in XPM support on Android.
(xbm_load, pbm_load, png_load_body, jpeg_load_body, gif_load)
(webp_load, imagemagick_load_image, svg_load): Use image file
descriptors on Android; these file descriptors may in fact
represent compressed asset streams, and obviate the necessity of
creating a new file descriptor for each asset image opened.
(Fimage_transforms_p): Report rotate90 on Android.
(image_types, syms_of_image): Enable built-in XPM support on
Android.

* src/fringe.c (init_fringe_bitmap): Bit swap bitmaps on Android,
as on X.

* src/frame.h (enum text_conversion_operation): New enumerator.
(struct text_conversion_action, struct text_conversion_state): New
variable.
(struct frame): New fields `tool_bar_wraps_p' and `conversion'.
Increase the width of `output_method'.
<output_data>: Add `android' field.
<wait_event_type>: Define on Android as well.
(fset_menu_bar_window): Define correctly, so that it's declared on
non-X builds without external menu bars.
(FRAME_ANDROID_P): Define macro.
(FRAME_WINDOW_P) [HAVE_ANDROID]: Define to FRAME_ANDROID_P.
(FRAME_RES): New macro.
(MOUSE_HL_INFO): Define without referencing tty output data on
Android, which doesn't have them.

* src/frame.c (Fframep): Return `android' on Android systems.
(Fwindow_system): Likewise.
(make_frame): Clear text conversion state and `tool_bar_wraps_p'.
(Fmake_terminal_frame): Signal that Android doesn't support text
terminals.
(delete_frame): Reset text conversion state prior to deleting the
frame.
(gui_display_get_resource): Don't call the resource hook on
Android.
(Fx_parse_geometry): Pacify compiler warning.
(make_monitor_attribute_list): Don't always use SOURCE if nil.
(syms_of_frame) <Qandroid>: New symbol.
<Vdefault_frame_scroll_bars>: Don't default scroll bars to an
enabled state on Android.

* src/fontset.c (fontset_find_font): Tackle an unusual problem.
* src/font.h (struct font_entity): New field `is_android'.
(PT_PER_INCH): Define to 160.00 on Android.

* src/font.c (font_make_entity): New function.
(font_make_entity_android): New variant that sets `is_android' to
true.
(font_pixel_size, font_find_for_lface, font_open_for_lface)
(Ffont_face_attributes, Fopen_font): Respect the distinction
between frame text and display scales.

* src/fns.c (Flocale_info): Silence compiler warning.

* src/filelock.c (BOOT_TIME): Undefine BOOT_TIME when building
libemacs.so
(get_boot_time, rename_lock_file, create_lock_file)
(current_lock_owner, make_lock_file_name, unlock_file): Employ
wrappers for Android filesystem operations.

* src/fileio.c (emacs_fd, emacs_fd_open, emacs_fd_close)
(emacs_fd_read, emacs_fd_lseek, emacs_fd_fstat, emacs_fd_valid_p):
New type and macros; define them to suitable values, akin to those
in lread.c
(check_vfs_filename): New function.
(file_access_p): Call `sys_faccessat'.
(close_file_unwind_emacs_fd): New function.
(fclose_unwind): Call `emacs_fclose', not fclose.
(file_name_directory): Export this function.
(user_homedir): If PW->pw_dir is not set and its uid is the
current user, call `android_get_home_directory'.
(get_homedir): Call `android_get_home_directory' if PW->pw_dir is
not set.
(Fcopy_file, Fmake_directory_internal, Fdelete_directory_internal)
(Fdelete_file, Frename_file, Fmake_symbolic_link, Faccess_file)
(file_directory_p, file_accessible_directory_p, Fset_file_modes)
(Fset_file_times, Ffile_newer_than_file_p, read_non_regular)
(Finsert_file_contents, write_region)
(Fverify_visited_file_modtime, Fset_visited_file_modtime)
(do_auto_save_unwind): Make use of Android filesystem wrappers and
file descriptors where possible.
(Fadd_name_to_file): Prohibit creating links to and from files
residing on Android special directories.
(Ffile_system_info): Avoid compilation failure on Android, where
Gnulib can't find out how to implement statfs.

* src/epaths.in [HAVE_ANDROID && !ANDROID_STUBIFY]: Deface this
file, so Makefile cannot change the hard-coded values within.

* src/emacs.c (using_utf8): Correctly initialize mbstate_t on
Android.
(init_cmdargs): Pass extra argument to openp.
(load_pdump): When building libemacs.so, use solely the file
provided on the command line or as an argument to
`android_emacs_init'.
(load_seccomp): Call sys_fstat, not fstat.
(main, android_emacs_init): Name `main' `android_emacs_init' when
building libemacs.so, and accept an argument designating the dump
file.
(main): Initialize text conversion and Android.  Don't presume
that argv is NULL terminated.
(Fkill_emacs, shut_down_emacs): Properly implement RESTART on
Android.
(syms_of_emacs) <Vsystem_type>: Describe the possible value
`android'.

* src/emacs-module.c (MODULE_HANDLE_NONLOCAL_EXIT): Cease relying
on GCC clean-up attribute extension.
(MODULE_INTERNAL_CLEANUP): New macro.
(module_make_global_ref, module_free_global_ref)
(module_make_function, module_get_function_finalizer)
(module_make_interactive, module_funcall, module_extract_integer)
(module_extract_float, module_copy_string_contents)
(module_get_user_ptr, module_set_user_ptr)
(module_get_user_finalizer, module_set_user_finalizer)
(module_vec_set, module_vec_size, module_process_input)
(module_extract_big_integer, module_make_big_integer): Carry out
necessary clean-up tasks using MODULE_HANDLE_NONLOCAL_EXIT.

* src/editfns.c (Fuser_full_name): Call `android_user_full_name',
as USER_FULL_NAME doesn't always work.

* src/doc.c (doc_fd, doc_fd_p, doc_open, doc_read_quit)
(doc_lseek): New types and macros, resembling those in lread.c.
(get_doc_string, Fsnarf_documentation): Implement in terms of
those macros, so as to use Android asset streams directly.

* src/dispnew.c (clear_current_matrices, clear_desired_matrices)
(allocate_matrices_for_window_redisplay, free_glyphs)
(redraw_frame, update_frame, scrolling, update_frame_line):
Disable support for text terminals when building for Android.
(Fopen_termscript): Use emacs_fclose.
(init_display_interactive): Set Vinitial_window_system to
Qandroid, and lose if Emacs needs to create a text terminal.

* src/dispextern.h (No_Cursor, Emacs_Rectangle, struct gui_box):
New definitions.
(struct glyph_string) <gc>: Define to the Android GC type.
(HAVE_NATIVE_TRANSPHORMS): Define on Android.
(struct image): New fields `ximg', `mask_img', as on X.
(enum tool_bar_item_idx): New tool bar item property
TOOL_BAR_ITEM_WRAP.

* src/dired.c (emacs_dir, emacs_closedir, emacs_readdir): New
typedef and definitions.
(open_directory): Return emacs_dir; use android_opendir on
Android, instead of at-funcs.
(directory_files_internal_unwind): Call emacs_closedir.
(read_dirent): Call emacs_readdir.
(directory_files_internal, file_name_completion)
(file_name_completion_dirp): Use Android wrappers for directories
and files.
(file_attributes): Abstain from openat on Android.

* src/conf_post.h (MB_CUR_MAX): Define to REPLACEMENT_MB_CUR_MAX
if necessary to counteract inept LLVM headers.

* src/coding.h (from_unicode_buffer): Define if HAVE_ANDROID as
well.

* src/coding.c (from_unicode_buffer): Define on Android, creating
a variant that understands UCS-16 extended into wchar_t.
(syms_of_coding) <Qutf_16le>: Define on Android.

* src/charset.c (load_charset_map_from_file): Supply extra
argument to openp, and call Emacs wrappers for fdopen and fclose.

* src/callproc.c (get_current_directory): Return the home
directory if ENCODED is a special directory.
(delete_temp_file): Call emacs_unlink in lieu of unlink.
(call_process): Use openp.
(emacs_spawn): Use Android executable loader binary if needed and
enabled.
(init_callproc): Set Vshell_file_name to /system/bin/sh if
libemacs.so.
(syms_of_callproc) <Vctags_program_name, Vetags_program_name,
Vhexl_program_name, Vemacsclient_program_name,
Vmovemail_program_name>: New variables.  Define to the names of
the programs they respectively stand for.

* src/callint.c (Fcall_interactively): Supply new argument in
calls to Fread_key_sequence and Fread_key_sequence_vector.

* src/buffer.h (struct buffer) <text_conversion_style_>: New bvar.
(bset_text_conversion_style): New bvar setter.

* src/buffer.c (init_buffer_once): Set the text conversion style.
(syms_of_buffer) <BVAR (current_buffer, text_conversion_style)>:
Define new BLV.

* src/androidvfs.c:
* src/androidterm.h:
* src/androidterm.c:
* src/androidselect.c:
* src/androidmenu.c:
* src/androidgui.h:
* src/androidfont.c:
* src/androidfns.c:
* src/android.h:
* src/android.c:
* src/android-emacs.c:
* src/android-asset.h: New function.

* src/alloc.c (cleanup_vector): Finalize Android font entities.
(find_string_data_in_pure) [__i386__ && !__clang__]: On Android,
compensate for a bug in the latest NDK GCC.
(mark_pinned_symbols, android_make_lisp_symbol): Elude another
bug in debuginfo generation with an almost nonsensical fix.
(garbage_collect): Mark androidterm and sfntfont.
(mark_frame): Mark text conversion actions and info.

* src/Makefile.in (XCONFIGURE): New variable.  If set, add srcdir
to vpath.
(hostlib): New variable, always defined to libgnu.a on the build
machine.
(GIF_CFLAGS, JPEG_CFLAGS, TIFF_CFLAGS, SQLITE3_CFLAGS)
(LIBSELINUX_CFLAGS, ANDROID_OBJ, ANDROID_LIBS, ANDROID_LDFLAGS)
(ANDROID_BUILD_CFLAGS, LIBGMP_CFLAGS): New variables.
(CM_OBJ): Update commentary.
(EMACS_CFLAGS): Add new compiler flags variables.
(base_obj): Add ANDROID_OBJ.
(SOME_MACHINE_OBJECTS): Add Android-related objects.
(lisp.mk): Generate from its absolute file name.
($(lispsource)/international/charprop.el): Don't generate when
building libemacs.so.
($(libsrc)/make-docfile$(EXEEXT)
$(libsrc)/make-fingerprint$(EXEEXT)): Depend on libgnu.a on the
build machine.
(mostlyclean): Remove libemacs.so.
(build-counter.c, libemacs.so, android-emacs): New targets.  These
targets are made from this Makefile copied to a subdirectory of
`cross', and provide the Emacs library and an ancillary binary
used by the Android port.

* nt/mingw-cfg.site:
* nt/gnulib-cfg.mk: Impede building Gnulib's vasnprintf* code.

* msdos/sedlibmk.inp:
* msdos/sedlibcf.inp:
* msdos/sed3v2.inp:
* msdos/sed1v2.inp: Fix the DJGPP build.

* make-dist (possibly_non_vc_files): Add exec/configure and
exec/config.h.in.

* m4/ndk-build.m4: New file.

* m4/getline.m4:
* m4/getdelim.m4:
* m4/asm-underscore.m4: Update from Gnulib.

* lisp/wid-edit.el (widget-event-point): Treat touch screen events
correctly.
(widget-keymap): Map touchscreen-begin to widget-button-click.
(widget-event-start): New function.
(widget-button--check-and-call-button):
(widget-button-click): Behave correctly when confronted by touch
screen events.

* lisp/version.el (android-read-build-system)
(android_read_build_time): New functions.
(emacs-build-system, emacs-repository-version-android)
(emacs-repository-get-version):
(emacs-repository-get-branch): Implement properly on Android, by
reading a file generated during the packaging process.

* lisp/touch-screen.el: New file, supplying support for
translating raw touch screen events into gestures.

* lisp/tool-bar.el (secondary-tool-bar-map): New defvar.
(tool-bar--cache-key, tool-bar--secondary-cache-key): Make
defsubsts.
(tool-bar--flush-key): Flush caches for the secondary tool bar as
well.
(tool-bar-make-keymap, tool-bar-make-keymap-1): Append the
secondary tool bar map below the primary tool bar map.
(modifier-bar-modifier-list): New variable.
(tool-bar-apply-modifiers, modifier-bar-button)
(tool-bar-event-apply-alt-modifier)
(tool-bar-event-apply-super-modifier)
(tool-bar-event-apply-hyper-modifier)
(tool-bar-event-apply-shift-modifier)
(tool-bar-event-apply-control-modifier)
(tool-bar-event-apply-meta-modifier, modifier-bar-available-p)
(modifier-bar-mode): New functions.

* lisp/textmodes/text-mode.el (text-mode): Set
text-conversion-style to t.

* lisp/textmodes/reftex-global.el (reftex-create-tags-file): Use
etags-program-name to provide the name of the etags program.
* lisp/textmodes/conf-mode.el (conf-mode-initialize): Enable text
conversion.
* lisp/textmodes/artist.el (artist-figlet-get-font-list): Use
/system/bin/sh on Android.

* lisp/term/android-win.el: New file.

* lisp/term.el (term-mode): Always display the on screen keyboard.
(term-exec-1): Use /system/bin/sh on Android.

* lisp/tab-line.el (tab-line-tab-map)
(tab-line-new-tab)
(tab-line-select-tab)
(tab-line-close-tab)
(tab-line-track-tap)
(tab-line-event-start): Improve support for touch screen events.

* lisp/tab-bar.el (tab-bar-mouse-context-menu):
(tab-bar-map): Likewise.
(tab-bar-handle-timeout, tab-bar-touchscreen-begin): New
functions.

* lisp/subr.el (event-start): Don't return nonsense if EVENT is a
touchscreen event.
(event-end): Likewise.
(read-key): Disable text conversion within
read-key-sequence-vector.
(read-char-choice-with-read-key): Display the on screen keyboard.
(read-char-from-minibuffer): Disable text conversion.
(use-dialog-box-p): Prefer dialog boxes on Android.
(y-or-n-p): Disable text conversion properly under all three modes
of operation.

* lisp/startup.el (android-fonts-enumerated): New variable.
(normal-top-level): Load system fonts on Android.

* lisp/speedbar.el (speedbar-fetch-etags-command): Use
etags-program-name instead of hard-coding `etags'.

* lisp/simple.el (normal-erase-is-backspace-setup-frame): Return
true on Android.
(event-apply-modifier): Correctly apply Shift and Control
modifiers to keys with other modifiers.
(undo-auto-amalgamate): Mention analyze-text-conversion wrt being
an amalgamating command.

* lisp/shell.el (shell--command-completion-data): Don't lose
if PATH contains an inaccessible directory.

* lisp/progmodes/prog-mode.el (prog-mode): Enable text conversion.
* lisp/progmodes/cperl-mode.el (cperl-etags): Don't hard-code
etags, employ etags-program-name instead.

* lisp/progmodes/cc-mode.el (c-initialize-cc-mode): Initialize
text conversion hook.
* lisp/progmodes/cc-cmds.el (c-post-text-conversion): New
function.  Do electric characters.

* lisp/play/gamegrid.el (gamegrid-setup-default-font): Don't crash
if the display resolution is too high.

* lisp/play/dunnet.el (text-conversion-style):
* lisp/play/doctor.el (doctor-mode): Enable text conversion.

* lisp/pixel-scroll.el (pixel-scroll-precision-scroll-down-page)
(pixel-scroll-precision-scroll-Up-page): Make autoloads.

* lisp/org/org-ctags.el (org-ctags-path-to-ctags): Use
ctags-program-name, not ctags.

* lisp/obsolete/terminal.el (terminal-emulator): Start
/system/bin/sh, not /bin/sh.

* lisp/net/tramp.el (tramp-encoding-shell): Use /system/bin/sh on
Android.

* lisp/net/eww.el (eww-form-submit, eww-form-file)
(eww-form-checkbox, eww-form-select): Define these faces on
Android as well.

* lisp/net/browse-url.el (browse-url-default-browser)
(browse-url--browser-defcustom-type): Specify on Android.
(browse-url-android-share, browse-url-default-android-browser):
New option and function.

* lisp/mwheel.el (mouse-wheel-down-event, mouse-wheel-up-event)
(mouse-wheel-left-event, mouse-wheel-right-event): Define suitably
on Android.

* lisp/mouse.el (minor-mode-menu-from-indicator): New argument
EVENT.  Use it for positioning the menu.
(mouse-minor-mode-menu): Pass EVENT to that function.

* lisp/minibuffer.el (clear-minibuffer-message): Don't clear the
message if `touch-screen-preview-select' may be underway.
(minibuffer-mode): Enable text conversion.
(minibuffer-setup-on-screen-keyboard)
(minibuffer-exit-on-screen-keyboard): New functions.

* lisp/menu-bar.el (menu-bar-close-window): New option.
(menu-bar-edit-menu): Bind execute-extended-command to a menu
item.
(kill-this-buffer, kill-this-buffer-enabled-p): Respect
menu-bar-close-window.

* lisp/mail/rmail.el (rmail-autodetect, rmail-insert-inbox-text):
Don't hard-code the name of movemail; rather, use
movemail-program-name.
* lisp/mail/emacsbug.el (emacs-build-description): Insert the
Android version and manufacturer.

* lisp/ls-lisp.el (ls-lisp-use-insert-directory-program): Default
to off on Android.

* lisp/loadup.el: Set load-list to empty load list after startup;
dump the first time Emacs starts, and load Android related
miscellanea.

* lisp/isearch.el (isearch-text-conversion-style): New variable.
(isearch-mode, isearch-done): Display the OSK, then temporarily
disable and restore the on screen keyboard.

* lisp/international/mule-cmds.el (set-coding-system-map): Update
menu definition for Android.

* lisp/international/fontset.el (script-representative-chars)
(setup-default-fontset): Improve detection of CJK fonts.

* lisp/image/wallpaper.el: Fix compiler warning.

* lisp/ielm.el (inferior-emacs-lisp-mode): Don't hard-code name of
hexl, replacing that with hexl-program-name.

* lisp/htmlfontify.el (hfy-etags-bin): Replace hard-coded Emacs
with etags-program-name.

* lisp/hexl.el (hexl-program): Replace hard-coded hexl.

* lisp/help-macro.el (make-help-screen): Display the on screen
keyboard and disable text conversion prior to reading options.

* lisp/gnus/mail-source.el (mail-source-movemail-program): Replace
hard-coded movemail with movemail-program-name.

* lisp/gnus/gnus-score.el (gnus-read-char): New function.
(gnus-summary-increase-score): Use a dialog box to display
these options on Android.

* lisp/frame.el (frame-geometry, frame-edges)
(mouse-absolute-pixel-position, set-mouse-absolute-pixel-position)
(frame-list-z-order, frame-restack, display-mouse-p)
(display-popup-menus-p, display-graphic-p, display-symbol-keys-p)
(display-screens, display-pixel-height, display-pixel-width)
(display-mm-height, display-mm-width, display-backing-store)
(display-save-under, display-planes, display-color-cells)
(display-visual-class, display-monitor-attributes-list): Implement
window system specific functions on Android.

* lisp/files.el (basic-save-buffer): Allow files to exist without
a parent directory.

* lisp/faces.el (tool-bar): Use default definition on Android.

* lisp/emacs-lisp/eldoc.el (eldoc-add-command-completions): Add
touch-screen-handle-touch and analyze-text-conversion.

* lisp/elec-pair.el (electric-pair-analyze-conversion): New
function.

* lisp/doc-view.el (doc-view-menu): Improve menu.
(doc-view-tool-bar-map): Add a new tool bar for Doc View.
(doc-view-new-search): New command.
(doc-view-mode): Enable that new tool bar.

* lisp/dired-aux.el (dired-do-chxxx, dired-do-chmod)
(dired-do-print, dired-do-shell-command, dired-do-compress-to)
(dired-do-create-files, dired-do-rename, dired-do-isearch)
(dired-do-isearch-regexp, dired-do-search)
(dired-do-query-replace-regexp, dired-do-find-regexp)
(dired-vc-next-action): Disable ``click to select'' after
running this command.
* lisp/dired.el (dired-insert-set-properties): Attach
click-to-select keymap to file names if necessary.
(dired-mode-map): Bind `touchscreen-hold' to click to select
mode.
(dired-post-do-command): New function.
(dired-do-delete): Call it.
(dired-mark-for-click, dired-enable-click-to-select-mode): New
functions.
(dired-click-to-select-mode): New minor mode.

* lisp/cus-edit.el (custom-button-mouse, custom-button-pressed)
(custom-display): Define faces to their default values on Android.

* lisp/comint.el (comint-mode): Enable text conversion.

* lisp/cedet/semantic/db-ebrowse.el
(semanticdb-create-ebrowse-database): Replace fixed ebrowse with
ebrowse-program-name.

* lisp/calc/calc.el (calc-mode): Display the on screen keyboard.
(calc): Insist on displaying the on screen keyboard.

* lisp/button.el (button-map): Bind touch screen events to
push-button.
(push-button): Deal with touch screen events.

* lisp/bindings.el (cut, paste, cut, text-conversion): New
bindings.

* lisp/battery.el (battery-status-function): Use
`battery-android'.
(battery-android): New function.

* lib/gnulib.mk.in:
* lib/getline.c:
* lib/getdelim.c:
* lib/Makefile.in: Update from Gnulib.

* lib-src/emacsclient.c (decode_options): Set `alt_display' to
`android'.

* lib-src/asset-directory-tool.c: New file.

* lib-src/Makefile.in: Adapt for cross-compilation.

* java/res/xml/preferences.xml:
* java/res/values/style.xml:
* java/res/values/strings.xml:
* java/res/values/bool.xml:
* java/res/values-v29/style.xml:
* java/res/values-v24/bool.xml:
* java/res/values-v19/bool.xml:
* java/res/values-v14/style.xml:
* java/res/values-v11/style.xml:
* java/org/gnu/emacs/EmacsWindowAttachmentManager.java:
* java/org/gnu/emacs/EmacsWindow.java:
* java/org/gnu/emacs/EmacsView.java:
* java/org/gnu/emacs/EmacsThread.java:
* java/org/gnu/emacs/EmacsSurfaceView.java:
* java/org/gnu/emacs/EmacsService.java:
* java/org/gnu/emacs/EmacsSdk8Clipboard.java:
* java/org/gnu/emacs/EmacsSdk7FontDriver.java:
* java/org/gnu/emacs/EmacsSdk23FontDriver.java:
* java/org/gnu/emacs/EmacsSdk11Clipboard.java:
* java/org/gnu/emacs/EmacsSafThread.java:
* java/org/gnu/emacs/EmacsPreferencesActivity.java:
* java/org/gnu/emacs/EmacsPixmap.java:
* java/org/gnu/emacs/EmacsOpenActivity.java:
* java/org/gnu/emacs/EmacsNoninteractive.java:
* java/org/gnu/emacs/EmacsNative.java:
* java/org/gnu/emacs/EmacsMultitaskActivity.java:
* java/org/gnu/emacs/EmacsLauncherPreferencesActivity.java:
* java/org/gnu/emacs/EmacsInputConnection.java:
* java/org/gnu/emacs/EmacsHolder.java:
* java/org/gnu/emacs/EmacsHandleObject.java:
* java/org/gnu/emacs/EmacsGC.java:
* java/org/gnu/emacs/EmacsFontDriver.java:
* java/org/gnu/emacs/EmacsFillRectangle.java:
* java/org/gnu/emacs/EmacsFillPolygon.java:
* java/org/gnu/emacs/EmacsDrawable.java:
* java/org/gnu/emacs/EmacsDrawRectangle.java:
* java/org/gnu/emacs/EmacsDrawPoint.java:
* java/org/gnu/emacs/EmacsDrawLine.java:
* java/org/gnu/emacs/EmacsDocumentsProvider.java:
* java/org/gnu/emacs/EmacsDirectoryEntry.java:
* java/org/gnu/emacs/EmacsDialogButtonLayout.java:
* java/org/gnu/emacs/EmacsDialog.java:
* java/org/gnu/emacs/EmacsCursor.java:
* java/org/gnu/emacs/EmacsContextMenu.java:
* java/org/gnu/emacs/EmacsClipboard.java:
* java/org/gnu/emacs/EmacsApplication.java:
* java/org/gnu/emacs/EmacsActivity.java:
* java/debug.sh:
* java/README:
* java/Makefile.in:
* java/INSTALL:
* java/AndroidManifest.xml.in:
* exec/trace.c:
* exec/test.c:
* exec/mipsfpu.h:
* exec/mipsfpu.c:
* exec/mipsel-user.h:
* exec/loader-x86_64.s:
* exec/loader-x86.s:
* exec/loader-mipsel.s:
* exec/loader-mips64el.s:
* exec/loader-armeabi.s:
* exec/loader-aarch64.s:
* exec/install-sh:
* exec/exec1.c:
* exec/exec.h:
* exec/exec.c:
* exec/deps.mk:
* exec/configure.ac:
* exec/config.sub:
* exec/config.h.in:
* exec/config.guess:
* exec/config-mips.m4.in:
* exec/README:
* exec/Makefile.in:
* etc/images/last-page.xpm: New files.

* etc/PROBLEMS: Expound upon problems with font instructing on
Android.

* etc/NEWS: Announce changes.

* etc/MACHINES: Describe support for Android.

* etc/DEBUG: Illustrate the steps to debug Emacs on Android.

* doc/lispref/processes.texi (Subprocess Creation):
* doc/lispref/os.texi (System Environment):
* doc/lispref/keymaps.texi (Translation Keymaps):
(Extended Menu Items):
(Tool Bar):
* doc/lispref/frames.texi (Frames):
(Frame Layout):
(Font and Color Parameters):
(Pop-Up Menus):
(Window System Selections):
* doc/lispref/elisp.texi (Top):
* doc/lispref/display.texi (Defining Faces):
(Window Systems):
* doc/lispref/commands.texi (Touchscreen Events):
(Touchscreen Events):
(Misc Events):
(Key Sequence Input):
* doc/emacs/windows.texi (Tab Line):
* doc/emacs/input.texi:
* doc/emacs/frames.texi (Tool Bars):
(Tab Bars):
* doc/emacs/emacs.texi (Top):
* doc/emacs/dired.texi (Marks vs Flags):
* doc/emacs/android.texi:
* doc/emacs/Makefile.in (EMACSSOURCES): Update the documentation
to properly describe changes effected.

* cross/verbose.mk.android:
* cross/ndk-build/ndk-resolve.mk:
* cross/ndk-build/ndk-prebuilt-static-library.mk:
* cross/ndk-build/ndk-prebuilt-shared-library.mk:
* cross/ndk-build/ndk-clear-vars.mk:
* cross/ndk-build/ndk-build.mk.in:
* cross/ndk-build/ndk-build-static-library.mk:
* cross/ndk-build/ndk-build-shared-library.mk:
* cross/ndk-build/ndk-build-executable.mk:
* cross/ndk-build/README:
* cross/ndk-build/Makefile.in:
* cross/langinfo.h:
* cross/README:
* cross/Makefile.in: New files.
* configure.ac: Configure Emacs for cross-compilation on Android.

* build-aux/ndk-module-extract.awk:
* build-aux/ndk-build-helper.mk:
* build-aux/ndk-build-helper-4.mk:
* build-aux/ndk-build-helper-3.mk:
* build-aux/ndk-build-helper-2.mk:
* build-aux/ndk-build-helper-1.mk:
* build-aux/makecounter.sh: New file.
* autogen.sh: Autogen in exec as well.

* admin/merge-gnulib (GNULIB_MODULES): Add getline, stpncpy and
strnlen.  Clean lib.

* README:
* Makefile.in:
* INSTALL: Update for Android.
* .dir-locals.el (c-mode): Add a few new types.

1 files changed, 1235 insertions, 0 deletions

diff --git a/exec/exec.c b/exec/exec.c
new file mode 100644
index 00000000000..0d9187cabfa
--- /dev/null
+++ b/exec/exec.c
@@ -0,0 +1,1235 @@
+/* Program execution for Emacs.
+
+Copyright (C) 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/>.  */
+
+#include <config.h>
+
+#include <errno.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <assert.h>
+#include <string.h>
+#include <ctype.h>
+#include <stdlib.h>
+
+#include <sys/ptrace.h>
+#include <sys/param.h>
+#include <sys/mman.h>
+
+#include "exec.h"
+
+#if defined __mips__ && !defined MIPS_NABI
+#include "mipsfpu.h"
+#endif /* defined __mips__ && !defined MIPS_NABI */
+
+
+
+
+/* Define replacements for required string functions.  */
+
+#if !defined HAVE_STPCPY || !defined HAVE_DECL_STPCPY
+
+/* Copy SRC to DEST, returning the address of the terminating '\0' in
+   DEST.  */
+
+static char *
+rpl_stpcpy (char *dest, const char *src)
+{
+  register char *d;
+  register const char *s;
+
+  d = dest;
+  s = src;
+
+  do
+    *d++ = *s;
+  while (*s++ != '\0');
+
+  return d - 1;
+}
+
+#define stpcpy rpl_stpcpy
+#endif /* !defined HAVE_STPCPY || !defined HAVE_DECL_STPCPY */
+
+#if !defined HAVE_STPNCPY || !defined HAVE_DECL_STPNCPY
+
+/* Copy no more than N bytes of SRC to DST, returning a pointer past
+   the last non-NUL byte written into DST.  */
+
+static char *
+rpl_stpncpy (char *dest, const char *src, size_t n)
+{
+  char c, *s;
+  size_t n4;
+
+  s = dest;
+
+  if (n >= 4)
+    {
+      n4 = n >> 2;
+
+      for (;;)
+        {
+          c = *src++;
+          *dest++ = c;
+          if (c == '\0')
+            break;
+          c = *src++;
+          *dest++ = c;
+          if (c == '\0')
+            break;
+          c = *src++;
+          *dest++ = c;
+          if (c == '\0')
+            break;
+          c = *src++;
+          *dest++ = c;
+          if (c == '\0')
+            break;
+          if (--n4 == 0)
+            goto last_chars;
+        }
+      n -= dest - s;
+      goto zero_fill;
+    }
+
+ last_chars:
+  n &= 3;
+  if (n == 0)
+    return dest;
+
+  for (;;)
+    {
+      c = *src++;
+      --n;
+      *dest++ = c;
+      if (c == '\0')
+        break;
+      if (n == 0)
+        return dest;
+    }
+
+ zero_fill:
+  while (n-- > 0)
+    dest[n] = '\0';
+
+  return dest - 1;
+}
+
+#define stpncpy rpl_stpncpy
+#endif /* !defined HAVE_STPNCPY || !defined HAVE_DECL_STPNCPY */
+
+
+
+/* Executable reading functions.
+   These functions extract information from an executable that is
+   about to be loaded.
+
+   `exec_0' takes the name of the program, determines whether or not
+   its format is correct, and if so, returns the list of actions that
+   the loader should perform.
+
+   The actions include:
+
+     - Making the stack executable, if PT_GNU_STACK.
+     - Mapping PT_LOAD sections into the executable with the correct
+       memory protection.
+     - On MIPS, setting the floating point register size.
+     - Transferring control to the interpreter or executable.  */
+
+
+/* Check whether or not FD starts with a #!, and return the executable
+   to load if it does.  Value is NAME if no interpreter character was
+   found, or the interpreter otherwise.  Value is NULL upon an IO
+   error.
+
+   If an additional command line argument is specified, place it in
+   *EXTRA.  */
+
+static const char *
+check_interpreter (const char *name, int fd, const char **extra)
+{
+  static char buffer[PATH_MAX], *start;
+  char first[2], *end, *ws;
+  ssize_t rc;
+
+  /* Read the first character.  */
+  rc = read (fd, &first, 2);
+
+  if (rc != 2)
+    goto fail;
+
+  if (first[0] != '#' || first[1] != '!')
+    goto nomatch;
+
+  rc = read (fd, buffer, PATH_MAX);
+
+  if (rc < 0)
+    goto fail;
+
+  /* Strip leading whitespace.  */
+  start = buffer;
+  while (*start && ((unsigned char) *start) < 128 && isspace (*start))
+    ++start;
+
+  /* Look for a newline character.  */
+  end = memchr (start, '\n', rc);
+
+  if (!end)
+    goto fail;
+
+  /* The string containing the interpreter is now in start.  NULL
+     terminate it.  */
+  *end = '\0';
+
+  /* Now look for any whitespace characters.  */
+  ws = strchr (start, ' ');
+
+  /* If there's no whitespace, return the entire start.  */
+
+  if (!ws)
+    {
+      if (lseek (fd, 0, SEEK_SET))
+        goto fail;
+
+      return start;
+    }
+
+  /* Otherwise, split the string at the whitespace and return the
+     additional argument.  */
+  *ws = '\0';
+
+  if (lseek (fd, 0, SEEK_SET))
+    goto fail;
+
+  *extra = ws + 1;
+  return start;
+
+ nomatch:
+  /* There's no interpreter.  */
+  if (lseek (fd, 0, SEEK_SET))
+    goto fail;
+
+  return name;
+
+ fail:
+  errno = ENOEXEC;
+  return NULL;
+}
+
+/* Static area used to store data placed on the loader's stack.  */
+static char loader_area[65536];
+
+/* Number of bytes used in that area.  */
+static int loader_area_used;
+
+
+
+/* Structure definitions for commands placed in the loader area.
+   Arrange these so that each member is naturally aligned.  */
+
+struct exec_open_command
+{
+  /* Word identifying the type of this command.  */
+  USER_WORD command;
+
+  /* NULL-terminated file name follows, padded to the size of a user
+     word.  */
+};
+
+struct exec_map_command
+{
+  /* Word identifying the type of this command.  */
+  USER_WORD command;
+
+  /* Where the file will be mapped.  */
+  USER_WORD vm_address;
+
+  /* Offset into the file to map from.  */
+  USER_WORD file_offset;
+
+  /* Memory protection for mprotect.  */
+  USER_WORD protection;
+
+  /* Number of bytes to be mapped.  */
+  USER_WORD length;
+
+  /* Flags for mmap.  */
+  USER_WORD flags;
+
+  /* Number of bytes to clear at the end of this mapping.  */
+  USER_WORD clear;
+};
+
+struct exec_jump_command
+{
+  /* Word identifying the type of this command.  */
+  USER_WORD command;
+
+  /* Address to jump to.  */
+  USER_WORD entry;
+
+  /* The value of AT_ENTRY inside the aux vector.  */
+  USER_WORD at_entry;
+
+  /* The value of AT_PHENT inside the aux vector.  */
+  USER_WORD at_phent;
+
+  /* The value of AT_PHNUM inside the aux vector.  */
+  USER_WORD at_phnum;
+
+  /* The value of AT_PHDR inside the aux vector.  */
+  USER_WORD at_phdr;
+
+  /* The value of AT_BASE inside the aux vector.  */
+  USER_WORD at_base;
+
+#if defined __mips__ && !defined MIPS_NABI
+  /* The FPU mode to apply.  */
+  USER_WORD fpu_mode;
+#endif /* defined __mips__ && !defined MIPS_NABI */
+};
+
+
+
+/* Write a command to open the file NAME to the loader area.
+   If ALTERNATE is true, then use the command code 16 instead
+   of 0.  Value is 1 upon failure, else 0.  */
+
+static int
+write_open_command (const char *name, bool alternate)
+{
+  struct exec_open_command command;
+  size_t size;
+
+  /* First, write the command to open NAME.  This is followed by NAME
+     itself, padded to sizeof (USER_WORD) bytes.  */
+
+  command.command = alternate ? 16 : 0;
+  if (sizeof loader_area - loader_area_used < sizeof command)
+    return 1;
+  memcpy (loader_area + loader_area_used, &command, sizeof command);
+  loader_area_used += sizeof command;
+
+  /* Calculate the length of NAME.  */
+  size = strlen (name) + 1;
+
+  /* Round it up.  */
+  size = ((size + (sizeof (USER_WORD) - 1))
+          & ~(sizeof (USER_WORD) - 1));
+
+  if (sizeof loader_area - loader_area_used < size)
+    return 1;
+
+  /* Now copy name to the loader area, filling the padding with NULL
+     bytes.  */
+  strncpy (loader_area + loader_area_used, name, size);
+
+  /* Increase loader_area_used.  */
+  loader_area_used += size;
+  return 0;
+}
+
+/* Write the commands necessary to map the executable file into memory
+   for the given PT_LOAD program HEADER.  Value is 1 upon failure,
+   else 0.  If USE_ALTERNATE, use the command code 17 instead of
+   1.
+
+   Apply the given OFFSET to virtual addresses that will be mapped.  */
+
+static int
+write_load_command (program_header *header, bool use_alternate,
+                    USER_WORD offset)
+{
+  struct exec_map_command command;
+  struct exec_map_command command1;
+  USER_WORD start, end;
+  bool need_command1;
+  static long pagesize;
+
+  /* First, write the commands necessary to map the specified segment
+     itself.
+
+     This is the area between header->p_vaddr and header->p_filesz,
+     rounded up to the page size.  */
+
+#ifndef PAGE_MASK
+  /* This system doesn't define a fixed page size.  */
+
+#ifdef HAVE_GETPAGESIZE
+  if (!pagesize)
+    pagesize = getpagesize ();
+#else /* HAVE_GETPAGESIZE */
+  if (!pagesize)
+    pagesize = sysconf (_SC_PAGESIZE);
+
+#define PAGE_MASK (~(pagesize - 1))
+#define PAGE_SIZE (pagesize)
+#endif /* HAVE_GETPAGESIZE */
+#endif /* PAGE_MASK */
+
+  start = header->p_vaddr & PAGE_MASK;
+  end = ((header->p_vaddr + header->p_filesz
+          + PAGE_SIZE)
+         & PAGE_MASK);
+
+  command.command = use_alternate ? 17 : 1;
+  command.vm_address = start;
+  command.file_offset = header->p_offset & PAGE_MASK;
+  command.protection = 0;
+  command.length = end - start;
+  command.clear = 0;
+  command.flags = MAP_PRIVATE | MAP_FIXED;
+
+  /* Apply the memory protection specified in the header.  */
+
+  if (header->p_flags & 4) /* PF_R */
+    command.protection |= PROT_READ;
+
+  if (header->p_flags & 2) /* PF_W */
+    command.protection |= PROT_WRITE;
+
+  if (header->p_flags & 1) /* PF_X */
+    command.protection |= PROT_EXEC;
+
+  /* Next, write any command necessary to map pages in the area
+     between p_filesz and p_memsz.  */
+  need_command1 = false;
+
+  if (header->p_memsz > header->p_filesz)
+    {
+      /* If there are bytes after end which need to be initialized, do
+         that now.  */
+      command.clear = end - header->p_vaddr - header->p_filesz;
+      start = end;
+      end = header->p_vaddr + header->p_memsz + PAGE_SIZE;
+      end &= PAGE_MASK;
+
+      if (end > start)
+        {
+          command1.command = 4;
+          command1.vm_address = start;
+          command1.file_offset = 0;
+          command1.length = end - start;
+          command1.clear = 0;
+          command1.protection = command.protection;
+          command1.flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED;
+          need_command1 = true;
+        }
+    }
+
+  /* Apply the offset to both commands if necessary.  */
+
+  if (offset)
+    {
+      if (need_command1)
+        command1.vm_address += offset;
+
+      command.vm_address += offset;
+    }
+
+  /* Write both commands.  */
+
+  if (sizeof loader_area - loader_area_used < sizeof command)
+    return 1;
+
+  memcpy (loader_area + loader_area_used, &command,
+          sizeof command);
+  loader_area_used += sizeof command;
+
+  if (!need_command1)
+    return 0;
+
+  if (sizeof loader_area - loader_area_used < sizeof command1)
+    return 1;
+
+  memcpy (loader_area + loader_area_used, &command1,
+          sizeof command1);
+  loader_area_used += sizeof command1;
+
+  return 0;
+}
+
+#if defined __mips__ && !defined MIPS_NABI
+
+/* Static storage used for MIPS ABI flags.  */
+static struct mips_elf_abi_flags exec_abi, interpreter_abi;
+
+/* Static storage for interpreter headers.  */
+static elf_header exec_interpreter_header;
+
+/* Pointer to the ELF header of this executable's interpreter.  */
+static elf_header *interpreter_header;
+
+/* Pointer to any PT_MIPS_ABIFLAGS program header found in the
+   executable itself.  */
+static struct mips_elf_abi_flags *exec_abiflags;
+
+/* Pointer to any PT_MIPS_ABIFLAGS program header found in the
+   executable's ELF interpreter.  */
+static struct mips_elf_abi_flags *interpreter_abiflags;
+
+#endif /* defined __mips__ && !defined MIPS_NABI */
+
+/* Process the specified program HEADER; HEADER is from the ELF
+   interpreter of another executable.  FD is the executable file from
+   which it is being read, NAME is its file name, and ELF_HEADER is
+   its header.
+
+   If ELF_HEADER->e_type is ET_DYN, add the base address for position
+   independent interpreter code to virtual addresses.
+
+   Value is 1 upon failure, else 0.  */
+
+static int
+process_interpreter_1 (const char *name, int fd,
+                       program_header *header,
+                       elf_header *elf_header)
+{
+  int rc;
+#if defined __mips__ && !defined MIPS_NABI
+  ssize_t rc1;
+#endif /* defined __mips__ && !defined MIPS_NABI */
+
+  switch (header->p_type)
+    {
+    default: /* PT_NULL, PT_NOTE, PT_DYNAMIC, PT_INTERP, et cetera */
+      rc = 0;
+      break;
+
+    case 1: /* PT_LOAD */
+      /* This describes a segment in the file that must be loaded.
+         Write the appropriate load command.  */
+
+      if (elf_header->e_type == 3) /* ET_DYN */
+        rc = write_load_command (header, true,
+                                 INTERPRETER_BASE);
+      else
+        rc = write_load_command (header, true, 0);
+
+      break;
+
+#if defined __mips__ && !defined MIPS_NABI
+    case 0x70000003: /* PT_MIPS_ABIFLAGS */
+      /* Record this header for later use.  */
+      rc1 = pread (fd, &interpreter_abi, sizeof interpreter_abi,
+                   header->p_offset);
+
+      if (rc1 != sizeof interpreter_abi)
+        return 1;
+
+      interpreter_abiflags = &interpreter_abi;
+      rc = 0;
+#endif /* defined __mips__ && !defined MIPS_NABI */
+    }
+
+  return rc;
+}
+
+/* Read the ELF interpreter specified in the given program header from
+   FD, and append the commands necessary to load it to the load area.
+   Then, return the interpreter entry point in *ENTRY.
+
+   Value is 1 upon failure, else 0.  */
+
+static int
+process_interpreter (int fd, program_header *prog_header,
+                     USER_WORD *entry)
+{
+  char buffer[PATH_MAX + 1];
+  int rc, size, i;
+  elf_header header;
+  program_header program;
+
+  /* Read the interpreter name.  */
+  size = MIN (prog_header->p_filesz, PATH_MAX);
+  rc = pread (fd, buffer, size, prog_header->p_offset);
+  if (rc < size)
+    return 1;
+
+  /* Make sure the name is NULL terminated.  */
+  buffer[size] = '\0';
+
+  /* Check if the file is executable.  This is unfortunately not
+     atomic.  */
+
+  if (access (buffer, X_OK))
+    return 1;
+
+  /* Read the interpreter's header much like exec_0.
+
+     However, use special command codes in `process_program_header' if
+     it is position independent.  That way, the loader knows it should
+     use the open interpreter instead.  */
+
+  fd = open (buffer, O_RDONLY);
+
+  if (fd < 0)
+    return 1;
+
+  rc = read (fd, &header, sizeof header);
+
+  if (rc < sizeof header)
+    goto fail;
+
+#if defined __mips__ && !defined MIPS_NABI
+  /* Record this interpreter's header for later use determining the
+     floating point ABI.  */
+  exec_interpreter_header = header;
+  interpreter_header = &exec_interpreter_header;
+#endif /* defined __mips__ && !defined MIPS_NABI */
+
+  /* Verify that this is indeed an ELF file.  */
+
+  if (header.e_ident[0] != 0x7f
+      || header.e_ident[1] != 'E'
+      || header.e_ident[2] != 'L'
+      || header.e_ident[3] != 'F')
+    goto fail;
+
+  /* Now check that the class is correct.  */
+#ifdef EXEC_64
+  if (header.e_ident[4] != 2)
+    goto fail;
+#else /* !EXEC_64 */
+  if (header.e_ident[4] != 1)
+    goto fail;
+#endif /* EXEC_64 */
+
+  /* And the endianness.  */
+#ifndef WORDS_BIGENDIAN
+  if (header.e_ident[5] != 1)
+    goto fail;
+#else /* WORDS_BIGENDIAN */
+  if (header.e_ident[5] != 2)
+    goto fail;
+#endif /* EXEC_64 */
+
+  /* Check that this is an executable.  */
+  if (header.e_type != 2 && header.e_type != 3)
+    goto fail;
+
+  /* Now check that the ELF program header makes sense.  */
+  if (header.e_phnum > 0xffff
+      || (header.e_phentsize
+          != sizeof (program_header)))
+    goto fail;
+
+  if (write_open_command (buffer, true))
+    goto fail;
+
+  for (i = 0; i < header.e_phnum; ++i)
+    {
+      rc = read (fd, &program, sizeof program);
+      if (rc < sizeof program)
+        goto fail;
+
+      if (process_interpreter_1 (buffer, fd, &program,
+                                 &header))
+        goto fail;
+    }
+
+  if (header.e_type == 3) /* ET_DYN */
+    *entry = header.e_entry + INTERPRETER_BASE;
+  else
+    *entry = header.e_entry;
+
+  close (fd);
+  return 0;
+
+ fail:
+  close (fd);
+  return 1;
+}
+
+/* Process the specified program HEADER.  FD is the executable file
+   from which it is being read, NAME is its file name, and ELF_HEADER
+   is its header.
+
+   If ELF_HEADER->e_type is ET_DYN, add the base address for position
+   independent code to virtual addresses.
+
+   If OFFSET is non-NULL, and *OFFSET is -1, write the virtual address
+   of HEADER if it describes a PT_LOAD segment.
+
+   If an interpreter is found, set *ENTRY to its entry point.
+
+   Value is 1 upon failure, else 0.  */
+
+static int
+process_program_header (const char *name, int fd,
+                        program_header *header,
+                        elf_header *elf_header,
+                        USER_WORD *entry,
+                        USER_WORD *offset)
+{
+  int rc;
+#if defined __mips__ && !defined MIPS_NABI
+  ssize_t rc1;
+#endif /* defined __mips__ && !defined MIPS_NABI */
+
+  switch (header->p_type)
+    {
+    default: /* PT_NULL, PT_NOTE, PT_DYNAMIC, et cetera */
+      rc = 0;
+      break;
+
+    case 1: /* PT_LOAD */
+      /* This describes a segment in the file that must be loaded.
+         Write the appropriate load command.  */
+
+      if (elf_header->e_type == 3) /* ET_DYN */
+        {
+          rc = write_load_command (header, false,
+                                   EXECUTABLE_BASE);
+
+          if (!rc && offset && *offset == (USER_WORD) -1)
+            *offset = EXECUTABLE_BASE + header->p_vaddr;
+        }
+      else
+        {
+          rc = write_load_command (header, false, 0);
+
+          if (!rc && offset && *offset == (USER_WORD) -1)
+            *offset = header->p_vaddr;
+        }
+
+      break;
+
+    case 3: /* PT_INTERP */
+      /* This describes another executable that must be loaded.  Open
+         the interpreter and process each of its headers as well.  */
+      rc = process_interpreter (fd, header, entry);
+      break;
+
+    case 1685382481: /* PT_GNU_STACK */
+      /* TODO */
+      rc = 0;
+      break;
+
+#if defined __mips__ && !defined MIPS_NABI
+    case 0x70000003: /* PT_MIPS_ABIFLAGS */
+      /* Record this header for later use.  */
+      rc1 = pread (fd, &exec_abi, sizeof exec_abi,
+                   header->p_offset);
+
+      if (rc1 != sizeof exec_abi)
+        return 1;
+
+      exec_abiflags = &exec_abi;
+      rc = 0;
+#endif /* defined __mips__ && !defined MIPS_NABI */
+    }
+
+  return rc;
+}
+
+/* Prepend one or two extra arguments ARG1 and ARG2 to a pending
+   execve system call.  Replace the argument immediately after
+   with ARG3.
+
+   TRACEE is the tracee performing the system call, and REGS are its
+   current user registers.  Value is 1 upon failure, else 0.  */
+
+static int
+insert_args (struct exec_tracee *tracee, USER_REGS_STRUCT *regs,
+             const char *arg1, const char *arg2, const char *arg3)
+{
+  USER_WORD argv, argc, word, new;
+  USER_WORD new1, new2, new3, i;
+  size_t text_size, effective_size;
+  USER_REGS_STRUCT original;
+
+  /* First, get a pointer to the current argument vector.  */
+  argv = regs->SYSCALL_ARG1_REG;
+
+  /* Now figure out how many arguments there are.  */
+  argc = 0;
+  while (true)
+    {
+      /* Clear errno.  PTRACE_PEEKDATA returns the word read the same
+         way failure indications are returned, so the only way to
+         catch IO errors is by clearing errno before the call to
+         ptrace and checking it afterwards.  */
+
+      errno = 0;
+      word = ptrace (PTRACE_PEEKDATA, tracee->pid,
+                     (void *) argv, NULL);
+      argv += sizeof (USER_WORD);
+
+      if (errno)
+        return 1;
+
+      if (!word)
+        break;
+
+      ++argc;
+    };
+
+  /* Allocate enough to hold that many arguments, alongside the argc
+     text.  */
+
+  text_size = (strlen (arg1) + 1
+               + (arg2 ? strlen (arg2) + 1 : 0)
+               + strlen (arg3) + 1);
+
+  /* Round it up to the user word size.  */
+  text_size += sizeof (USER_WORD) - 1;
+  text_size &= ~(sizeof (USER_WORD) - 1);
+
+  /* Now allocate the new argv.  Make sure argc is at least 1; it
+     needs to hold ARG3.  */
+
+  effective_size = sizeof word * (MAX (1, argc) + 2) + text_size;
+
+  if (arg2)
+    effective_size += sizeof word;
+
+  /* Copy regs to original so that user_alloca knows it should append
+     the ABI red zone.  */
+
+  memcpy (&original, regs, sizeof *regs);
+  new = user_alloca (tracee, &original, regs,
+                     effective_size);
+
+  if (!new)
+    goto fail;
+
+  /* Figure out where argv starts.  */
+
+  new3 = new + text_size;
+
+  /* Now write the first two strings.  */
+
+  new1 = new + strlen (arg1) + 1;
+  new2 = new1 + (arg2 ? strlen (arg2) + 1 : 0);
+
+  if (user_copy (tracee, (const unsigned char *) arg1,
+                 new, new1 - new))
+    goto fail;
+
+  if (arg2 && user_copy (tracee, (const unsigned char *) arg2,
+                         new1, new2 - new1))
+    goto fail;
+
+  /* Write the replacement arg3, the file name of the executable.  */
+
+  if (user_copy (tracee, (const unsigned char *) arg3,
+                 new2, new3 - new2))
+    goto fail;
+
+  /* Start copying argv back to new2.  First, write the one or two new
+     arguments.  */
+
+  if (ptrace (PTRACE_POKETEXT, tracee->pid,
+              (void *) new3, (void *) new))
+    goto fail;
+
+  new3 += sizeof new3;
+
+  if (arg2 && ptrace (PTRACE_POKETEXT, tracee->pid,
+                      (void *) new3, (void *) new1))
+    goto fail;
+  else if (arg2)
+    new3 += sizeof new3;
+
+  /* Next, write the third argument.  */
+
+  if (ptrace (PTRACE_POKETEXT, tracee->pid, (void *) new3,
+              (void *) new2))
+    goto fail;
+
+  new3 += sizeof new3;
+
+  /* Copy the remaining arguments back.  */
+
+  argv = regs->SYSCALL_ARG1_REG;
+
+  if (argc)
+    {
+      /* Make sure the trailing NULL is included.  */
+      argc += 1;
+
+      /* Now copy each argument in argv, starting from argv[1].  */
+
+      for (i = 1; i < argc; ++i)
+        {
+          /* Read one argument.  */
+          word = ptrace (PTRACE_PEEKDATA, tracee->pid,
+                         (void *) (argv + i * sizeof argv), NULL);
+
+          /* Write one argument, then increment new3.  */
+
+          if (ptrace (PTRACE_POKETEXT, tracee->pid,
+                      (void *) new3, (void *) word))
+            goto fail;
+
+          new3 += sizeof new3;
+        }
+    }
+  else
+    {
+      /* Just write the trailing NULL.  */
+
+      if (ptrace (PTRACE_POKETEXT, tracee->pid,
+                  (void *) new3, (void *) 0))
+        goto fail;
+
+      new3 += sizeof new3;
+    }
+
+  /* Assert that new3 is not out of bounds.  */
+  assert (new3 == new + effective_size);
+
+  /* And that it is properly aligned.  */
+  assert (!(new3 & (sizeof new3 - 2)));
+
+  /* Now modify the system call argument to point to new +
+     text_size.  */
+
+  regs->SYSCALL_ARG1_REG = new + text_size;
+
+#ifdef __aarch64__
+  if (aarch64_set_regs (tracee->pid, regs, false))
+    goto fail;
+#else /* !__aarch64__ */
+  if (ptrace (PTRACE_SETREGS, tracee->pid, NULL, regs))
+    goto fail;
+#endif /* __aarch64__ */
+
+  /* Success.  */
+
+  return 0;
+
+ fail:
+  /* Restore the original stack pointer.  */
+#ifdef __aarch64__
+  aarch64_set_regs (tracee->pid, &original, false);
+#else /* !__aarch64__ */
+  ptrace (PTRACE_SETREGS, tracee->pid, NULL, &original);
+#endif /* __aarch64__ */
+  errno = ENOMEM;
+  return 1;
+}
+
+
+
+/* Format PID, an unsigned process identifier, in base 10.  Place the
+   result in *IN, and return a pointer to the byte after the
+   result.  REM should be NULL.  */
+
+static char *
+format_pid (char *in, unsigned int pid)
+{
+  unsigned int digits[32], *fill;
+
+  fill = digits;
+
+  for (; pid != 0; pid = pid / 10)
+    *fill++ = pid % 10;
+
+  /* Insert 0 if the number would otherwise be empty.  */
+
+  if (fill == digits)
+    *fill++ = 0;
+
+  while (fill != digits)
+    {
+      --fill;
+      *in++ = '0' + *fill;
+    }
+
+  *in = '\0';
+  return in;
+}
+
+/* Return a sequence of actions required to load the executable under
+   the file NAME for the given TRACEE.  First, see if the file starts
+   with #!; in that case, find the program to open and use that
+   instead.
+
+   If REENTRANT is not defined, NAME is actually a buffer of size
+   PATH_MAX + 80.  In that case, copy over the file name actually
+   opened.
+
+   Next, read the executable header, and add the necessary memory
+   mappings for each file.  Finally, return the action data and its
+   size in *SIZE.
+
+   Finally, use REGS to add the required interpreter arguments to the
+   caller's argv.
+
+   Value is NULL upon failure, with errno set accordingly.  */
+
+char *
+exec_0 (char *name, struct exec_tracee *tracee,
+        size_t *size, USER_REGS_STRUCT *regs)
+{
+  int fd, rc, i;
+  elf_header header;
+  const char *interpreter_name, *extra;
+  program_header program;
+  USER_WORD entry, program_entry, offset;
+  USER_WORD header_offset;
+  struct exec_jump_command jump;
+#if defined __mips__ && !defined MIPS_NABI
+  int fpu_mode;
+#endif /* defined __mips__ && !defined MIPS_NABI */
+  char buffer[80], buffer1[PATH_MAX + 80], *rewrite;
+  ssize_t link_size;
+  size_t remaining;
+
+  /* If the process is trying to run /proc/self/exe, make it run
+     itself instead.  */
+
+  if (!strcmp (name, "/proc/self/exe") && tracee->exec_file)
+    {
+      strncpy (name, tracee->exec_file, PATH_MAX - 1);
+      name[PATH_MAX] = '\0';
+    }
+  else
+    {
+      /* If name is not absolute, then make it relative to TRACEE's
+         cwd.  Use stpcpy, as sprintf is not reentrant.  */
+
+      if (name[0] && name[0] != '/')
+        {
+          /* Clear `buffer'.  */
+          memset (buffer, 0, sizeof buffer);
+          memset (buffer1, 0, sizeof buffer);
+
+          /* Copy over /proc, the PID, and /cwd/.  */
+          rewrite = stpcpy (buffer, "/proc/");
+          rewrite = format_pid (rewrite, tracee->pid);
+          strcpy (rewrite, "/cwd");
+
+          /* Resolve this symbolic link.  */
+
+          link_size = readlink (buffer, buffer1,
+                                PATH_MAX + 1);
+
+          if (link_size < 0)
+            return NULL;
+
+          /* Check that the name is a reasonable size.  */
+
+          if (link_size > PATH_MAX)
+            {
+              /* The name is too long.  */
+              errno = ENAMETOOLONG;
+              return NULL;
+            }
+
+          /* Add a directory separator if necessary.  */
+      
+          if (!link_size || buffer1[link_size - 1] != '/')
+            buffer1[link_size] = '/', link_size++;
+
+          rewrite = buffer1 + link_size;
+          remaining = buffer1 + sizeof buffer1 - rewrite - 1;
+          rewrite = stpncpy (rewrite, name, remaining);
+
+          /* Replace name with buffer1.  */
+#ifndef REENTRANT
+          strcpy (name, buffer1);
+#endif /* REENTRANT */
+        }
+    }
+
+  /* Check that the file is accessible and executable.  */
+
+  if (access (name, X_OK))
+    return NULL;
+
+  fd = open (name, O_RDONLY);
+  if (fd < 0)
+    return NULL;
+
+  /* Now read the header.  */
+
+  extra = NULL;
+  interpreter_name = check_interpreter (name, fd, &extra);
+  if (!interpreter_name)
+    goto fail;
+
+  /* Open the interpreter instead, if necessary.  */
+  if (interpreter_name != name)
+    {
+      close (fd);
+      fd = open (interpreter_name, O_RDONLY);
+      if (fd < 0)
+        return NULL;
+
+      /* Now, rewrite the argument list to include `interpreter_name'
+         and perhaps `extra'.  */
+
+      if (insert_args (tracee, regs, interpreter_name,
+                       extra, name))
+        goto fail1;
+    }
+
+  rc = read (fd, &header, sizeof header);
+
+  if (rc < sizeof header)
+    goto fail1;
+
+  /* Verify that this is indeed an ELF file.  */
+
+  if (header.e_ident[0] != 0x7f
+      || header.e_ident[1] != 'E'
+      || header.e_ident[2] != 'L'
+      || header.e_ident[3] != 'F')
+    goto fail1;
+
+  /* Now check that the class is correct.  */
+#ifdef EXEC_64
+  if (header.e_ident[4] != 2)
+    goto fail1;
+#else /* !EXEC_64 */
+  if (header.e_ident[4] != 1)
+    goto fail1;
+#endif /* EXEC_64 */
+
+  /* And the endianness.  */
+#ifndef WORDS_BIGENDIAN
+  if (header.e_ident[5] != 1)
+    goto fail1;
+#else /* WORDS_BIGENDIAN */
+  if (header.e_ident[5] != 2)
+    goto fail1;
+#endif /* EXEC_64 */
+
+  /* Check that this is an executable.  */
+  if (header.e_type != 2 && header.e_type != 3)
+    goto fail1;
+
+  /* Now check that the ELF program header makes sense.  */
+  if (header.e_phnum > 0xffff
+      || (header.e_phentsize
+          != sizeof (program_header)))
+    goto fail1;
+
+  /* Seek to the first program header and read each one.  */
+  rc = lseek (fd, header.e_phoff, SEEK_SET);
+  if (rc < 0)
+    goto fail1;
+  loader_area_used = 0;
+
+  /* Write the command used to open the executable.  */
+  if (write_open_command (interpreter_name, false))
+    goto fail1;
+
+  /* Apply base addresses for PIC code.  */
+
+  if (header.e_type == 3) /* ET_DYN */
+    offset = EXECUTABLE_BASE;
+  else
+    offset = 0;
+
+  /* entry and program_entry are initially the same, but entry may be
+     set to that of the interpreter if one is present.  */
+
+  entry = header.e_entry + offset;
+  program_entry = header.e_entry;
+
+#if defined __mips__ && !defined MIPS_NABI
+  /* Clear MIPS ABI flags.  */
+  exec_abiflags = NULL;
+  interpreter_abiflags = NULL;
+  interpreter_header = NULL;
+#endif /* defined __mips__ && !defined MIPS_NABI */
+
+  /* Set header_offset to -1; `process_program_header' then updates it
+     to that of the first mapping.  */
+  header_offset = -1;
+
+  for (i = 0; i < header.e_phnum; ++i)
+    {
+      rc = read (fd, &program, sizeof program);
+      if (rc < sizeof program)
+        goto fail1;
+
+      if (process_program_header (interpreter_name, fd,
+                                  &program, &header,
+                                  &entry, &header_offset))
+        goto fail1;
+    }
+
+  /* Write the entry point and program entry.  */
+
+  jump.command = 3;
+  jump.entry = entry;
+
+  /* Now calculate values for the aux vector.  */
+
+  jump.at_entry = program_entry + offset;
+  jump.at_phent = header.e_phentsize;
+  jump.at_phnum = header.e_phnum;
+  jump.at_base = (entry == header.e_entry + offset
+                  ? EXECUTABLE_BASE
+                  : INTERPRETER_BASE);
+
+#if defined __mips__ && !defined MIPS_NABI
+  /* Finally, calculate the FPU mode wanted by the executable.  */
+
+  if (determine_fpu_mode (&header, interpreter_header,
+                          &fpu_mode, exec_abiflags,
+                          interpreter_abiflags))
+    /* N.B. that `determine_fpu_mode' sets errno.  */
+    goto fail;
+
+  /* If the processor is too new to support FR0 operation, place the
+     executable in floating point emulation mode.  */
+
+  if (fpu_mode == FP_FR0 && !cpu_supports_fr0_p ())
+    fpu_mode = FP_FRE;
+
+  jump.fpu_mode = fpu_mode;
+#endif /* defined __mips__ && !defined MIPS_NABI */
+
+  /* The offset used for at_phdr should be that of the first
+     mapping.  */
+
+  if (header_offset == (USER_WORD) -1)
+    header_offset = 0;
+
+  jump.at_phdr = header.e_phoff + header_offset;
+
+  if (sizeof loader_area - loader_area_used < sizeof jump)
+    goto fail1;
+
+  memcpy (loader_area + loader_area_used, &jump,
+          sizeof jump);
+  loader_area_used += sizeof jump;
+
+  /* Close the file descriptor and return the number of bytes
+     used.  */
+
+  close (fd);
+  *size = loader_area_used;
+
+  /* Make sure the loader area is properly aligned.  */
+  assert (!(loader_area_used & (sizeof (USER_WORD) - 1)));
+  return loader_area;
+
+ fail1:
+  errno = ENOEXEC;
+ fail:
+  close (fd);
+  return NULL;
+}