Compute C decls for DEFSYMs automatically

Compute C decls for DEFSYMs automatically

Fixes Bug#15880.
This patch also makes Q constants (e.g., Qnil) constant addresses
from the C point of view.
* make-docfile.c: Revamp to generate table of symbols, too.
Include <stdbool.h>.
(xstrdup): New function.
(main): Don't process the same file twice.
(SYMBOL): New constant in enum global_type.
(struct symbol): Turn 'value' member into a union, either v.value
for int or v.svalue for string.  All uses changed.
(add_global): New arg svalue, which overrides value, so that globals
can have a string value.
(close_emacs_global): New arg num_symbols; all uses changed.
Output lispsym decl.
(write_globals): Output symbol globals too.  Output more
ATTRIBUTE_CONST, now that Qnil etc. are C constants.
Output defsym_name table.
(scan_c_file): Move most of guts into ...
(scan_c_stream): ... new function.  Scan for DEFSYMs and
record symbols found.  Don't read past EOF if file doesn't
end in newline.
* alloc.c, bidi.c, buffer.c, bytecode.c, callint.c, casefiddle:
* casetab.c, category.c, ccl.c, charset.c, chartab.c, cmds.c, coding.c:
* composite.c, data.c, dbusbind.c, decompress.c, dired.c, dispnew.c:
* doc.c, editfns.c, emacs.c, eval.c, fileio.c, fns.c, font.c, fontset.c:
* frame.c, fringe.c, ftfont.c, ftxfont.c, gfilenotify.c, gnutls.c:
* image.c, inotify.c, insdel.c, keyboard.c, keymap.c, lread.c:
* macfont.m, macros.c, minibuf.c, nsfns.m, nsfont.m, nsimage.m:
* nsmenu.m, nsselect.m, nsterm.m, print.c, process.c, profiler.c:
* search.c, sound.c, syntax.c, term.c, terminal.c, textprop.c, undo.c:
* window.c, xdisp.c, xfaces.c, xfns.c, xftfont.c, xmenu.c, xml.c:
* xselect.c, xsettings.c, xterm.c:
Remove Q vars that represent symbols (e.g., Qnil, Qt, Qemacs).
These names are now defined automatically by make-docfile.
* alloc.c (init_symbol): New function.
(Fmake_symbol): Use it.
(c_symbol_p): New function.
(valid_lisp_object_p, purecopy): Use it.
* alloc.c (marked_pinned_symbols):
Use make_lisp_symbol instead of make_lisp_ptr.
(garbage_collect_1): Mark lispsym symbols.
(CHECK_ALLOCATED_AND_LIVE_SYMBOL): New macro.
(mark_object): Use it.
(sweep_symbols): Sweep lispsym symbols.
(symbol_uses_obj): New function.
(which_symbols): Use it.  Work for lispsym symbols, too.
(init_alloc_once): Initialize Vpurify_flag here; no need to wait,
since Qt's address is already known now.
(syms_of_alloc): Add lispsym count to symbols_consed.
* buffer.c (init_buffer_once): Compare to Qnil, not to make_number (0),
when testing whether storage is all bits zero.
* dispextern (struct image_type):
* font.c (font_property_table):
* frame.c (struct frame_parm_table, frame_parms):
* keyboard.c (scroll_bar_parts, struct event_head):
* xdisp.c (struct props):
Use XSYMBOL_INIT (Qfoo) and struct Lisp_Symbol * rather than &Qfoo and
Lisp_Object *, since Qfoo is no longer an object whose address can be
taken.  All uses changed.
* eval.c (run_hook): New function.  Most uses of Frun_hooks changed to
use it, so that they no longer need to take the address of a Lisp sym.
(syms_of_eval): Don't use DEFSYM on Vrun_hooks, as it's a variable.
* frame.c (syms_of_frame): Add defsyms for the frame_parms table.
* keyboard.c (syms_of_keyboard): Don't DEFSYM Qmenu_bar here.
DEFSYM Qdeactivate_mark before the corresponding var.
* keymap.c (syms_of_keymap): Use DEFSYM for Qmenu_bar and Qmode_line
instead of interning their symbols; this avoids duplicates.
(LISP_INITIALLY, TAG_PTR)
(DEFINE_LISP_SYMBOL_BEGIN, DEFINE_LISP_SYMBOL_END, XSYMBOL_INIT):
New macros.
(LISP_INITIALLY_ZERO): Use it.
(enum symbol_interned, enum symbol_redirect, struct Lisp_Symbol)
(EXFUN, DEFUN_ARGS_MANY, DEFUN_ARGS_UNEVALLED, DEFUN_ARGS_*):
Move decls up, to avoid forward uses.  Include globals.h earlier, too.
(make_lisp_symbol): New function.
(XSETSYMBOL): Use it.
(DEFSYM): Now just a placeholder for make-docfile.
* lread.c (DEFINE_SYMBOLS): Define, for globals.h.
(intern_sym): New function, with body taken from old intern_driver.
(intern_driver): Use it.  Last arg is now Lisp integer, not ptrdiff_t.
All uses changed.
(define_symbol): New function.
(init_obarray): Define the C symbols taken from lispsym.
Use plain DEFSYM for Qt and Qnil.
* syntax.c (init_syntax_once): No need to worry about
Qchar_table_extra_slots.