1------------------------------------------------------------------------------
2--                                                                          --
3--                          GNAT SYSTEM UTILITIES                           --
4--                                                                          --
5--                               X E I N F O                                --
6--                                                                          --
7--                                 B o d y                                  --
8--                                                                          --
9--          Copyright (C) 1992-2019, Free Software Foundation, Inc.         --
10--                                                                          --
11-- GNAT is free software;  you can  redistribute it  and/or modify it under --
12-- terms of the  GNU General Public License as published  by the Free Soft- --
13-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
14-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
15-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
16-- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
17-- for  more details.  You should have  received  a copy of the GNU General --
18-- Public License  distributed with GNAT; see file COPYING3.  If not, go to --
19-- http://www.gnu.org/licenses for a complete copy of the license.          --
20--                                                                          --
21-- GNAT was originally developed  by the GNAT team at  New York University. --
22-- Extensive contributions were provided by Ada Core Technologies Inc.      --
23--                                                                          --
24------------------------------------------------------------------------------
25
26--  Program to construct C header file einfo.h (C version of einfo.ads spec)
27--  for use by Gigi. This header file contains all definitions and access
28--  functions, but does not contain set procedures, since Gigi is not allowed
29--  to modify the GNAT tree.
30
31--    Input files:
32
33--       einfo.ads     spec of Einfo package
34--       einfo.adb     body of Einfo package
35
36--    Output files:
37
38--       einfo.h       corresponding C header file
39
40--  Note: It is assumed that the input files have been compiled without errors
41
42--  An optional argument allows the specification of an output file name to
43--  override the default einfo.h file name for the generated output file.
44
45--  Most, but not all of the functions in Einfo can be inlined in the C header.
46--  They are the functions identified by pragma Inline in the spec. Functions
47--  that cannot be inlined are simply defined in the header.
48
49with Ada.Command_Line;              use Ada.Command_Line;
50with Ada.Strings.Unbounded;         use Ada.Strings.Unbounded;
51with Ada.Strings.Unbounded.Text_IO; use Ada.Strings.Unbounded.Text_IO;
52with Ada.Strings.Maps;              use Ada.Strings.Maps;
53with Ada.Strings.Maps.Constants;    use Ada.Strings.Maps.Constants;
54with Ada.Text_IO;                   use Ada.Text_IO;
55
56with GNAT.Spitbol;                  use GNAT.Spitbol;
57with GNAT.Spitbol.Patterns;         use GNAT.Spitbol.Patterns;
58with GNAT.Spitbol.Table_Boolean;    use GNAT.Spitbol.Table_Boolean;
59
60with CEinfo;
61
62procedure XEinfo is
63
64   package TB renames GNAT.Spitbol.Table_Boolean;
65
66   Err : exception;
67
68   A         : VString := Nul;
69   B         : VString := Nul;
70   C         : VString := Nul;
71   Expr      : VString := Nul;
72   Filler    : VString := Nul;
73   Fline     : VString := Nul;
74   Formal    : VString := Nul;
75   Formaltyp : VString := Nul;
76   FN        : VString := Nul;
77   Line      : VString := Nul;
78   N         : VString := Nul;
79   N1        : VString := Nul;
80   N2        : VString := Nul;
81   N3        : VString := Nul;
82   Nam       : VString := Nul;
83   Name      : VString := Nul;
84   NewS      : VString := Nul;
85   Nextlin   : VString := Nul;
86   OldS      : VString := Nul;
87   Rtn       : VString := Nul;
88   Term      : VString := Nul;
89
90   InB : File_Type;
91   --  Used to read initial header from body
92
93   InF   : File_Type;
94   --  Used to read full text of both spec and body
95
96   Ofile : File_Type;
97   --  Used to write output file
98
99   wsp      : constant Pattern := NSpan (' ' & ASCII.HT);
100   Comment  : constant Pattern := wsp & "--";
101   For_Rep  : constant Pattern := wsp & "for";
102   Get_Func : constant Pattern := wsp * A & "function" & wsp
103                                  & Break (' ') * Name;
104   Inline   : constant Pattern := wsp & "pragma Inline (" & Break (')') * Name;
105   Get_Pack : constant Pattern := wsp & "package ";
106   Get_Enam : constant Pattern := wsp & Break (',') * N & ',';
107   Find_Fun : constant Pattern := wsp & "function";
108   F_Subtyp : constant Pattern := wsp * A & "subtype " & Break (' ') * N;
109   G_Subtyp : constant Pattern := wsp & "subtype" & wsp & Break (' ') * NewS
110                                  & wsp & "is" & wsp & Break (" ;") * OldS
111                                  & wsp & ';' & wsp & Rtab (0);
112   F_Typ    : constant Pattern := wsp * A & "type " & Break (' ') * N &
113                                  " is (";
114   Get_Nam  : constant Pattern := wsp * A & Break (",)") * Nam
115                                  & Len (1) * Term;
116   Get_Styp : constant Pattern := wsp * A & "subtype " & Break (' ') * N;
117   Get_N1   : constant Pattern := wsp & Break (' ') * N1;
118   Get_N2   : constant Pattern := wsp & "-- " & Rest * N2;
119   Get_N3   : constant Pattern := wsp & Break (';') * N3;
120   Get_FN   : constant Pattern := wsp * C & "function" & wsp
121                                  & Break (" (") * FN;
122   Is_Rturn : constant Pattern := BreakX ('r') & "return";
123   Is_Begin : constant Pattern := wsp & "begin";
124   Get_Asrt : constant Pattern := wsp & "pragma Assert";
125   Semicoln : constant Pattern := BreakX (';');
126   Get_Cmnt : constant Pattern := BreakX ('-') * A & "--";
127   Get_Expr : constant Pattern := wsp & "return " & Break (';') * Expr;
128   Chek_End : constant Pattern := wsp & "end" & BreakX (';') & ';';
129   Get_B1   : constant Pattern := BreakX (' ') * A & " in " & Rest * B;
130   Get_B2   : constant Pattern := BreakX (' ') * A & " = " & Rest * B;
131   Get_B3   : constant Pattern := BreakX (' ') * A & " /= " & Rest * B;
132   Get_B4   : constant Pattern := BreakX (' ') * A & " or else " & Rest * B;
133   To_Paren : constant Pattern := wsp * Filler & '(';
134   Get_Fml  : constant Pattern := Break (" :") * Formal & wsp & ':' & wsp
135                                  & BreakX (" );") * Formaltyp;
136   Nxt_Fml  : constant Pattern := wsp & "; ";
137   Get_Rtn  : constant Pattern := wsp & "return" & wsp & BreakX (" ;") * Rtn;
138   Rem_Prn  : constant Pattern := wsp & ')';
139
140   M : Match_Result;
141
142   Lineno : Natural := 0;
143   --  Line number in spec
144
145   V   : Natural;
146   Ctr : Natural;
147
148   Inlined : TB.Table (200);
149   --  Inlined<N> = True for inlined function, False otherwise
150
151   Lastinlined : Boolean;
152
153   procedure Badfunc;
154   pragma No_Return (Badfunc);
155   --  Signal bad function in body
156
157   function Getlin return VString;
158   --  Get non-comment line (comment lines skipped, also skips FOR rep clauses)
159   --  Fatal error (raises End_Error exception) if end of file encountered
160
161   procedure Must (B : Boolean);
162   --  Raises Err if the argument (a Match) call, returns False
163
164   procedure Sethead (Line : in out VString; Term : String);
165   --  Process function header into C
166
167   -------------
168   -- Badfunc --
169   -------------
170
171   procedure Badfunc is
172   begin
173      Put_Line
174        (Standard_Error,
175         "Body for function " & FN & " does not meet requirements");
176      raise Err;
177   end Badfunc;
178
179   -------------
180   -- Getlin --
181   -------------
182
183   function Getlin return VString is
184      Lin : VString;
185
186   begin
187      loop
188         Lin := Get_Line (InF);
189         Lineno := Lineno + 1;
190
191         if Lin /= ""
192           and then not Match (Lin, Comment)
193           and then not Match (Lin, For_Rep)
194         then
195            return Lin;
196         end if;
197      end loop;
198   end Getlin;
199
200   ----------
201   -- Must --
202   ----------
203
204   procedure Must (B : Boolean) is
205   begin
206      if not B then
207         raise Err;
208      end if;
209   end Must;
210
211   -------------
212   -- Sethead --
213   -------------
214
215   procedure Sethead (Line : in out VString; Term : String) is
216      Args : VString;
217
218   begin
219      Must (Match (Line, Get_Func, ""));
220      Args := Nul;
221
222      if Match (Line, To_Paren, "") then
223         Args := Filler & '(';
224
225         loop
226            Must (Match (Line, Get_Fml, ""));
227            Append (Args, Formaltyp & ' ' & Formal);
228            exit when not Match (Line, Nxt_Fml);
229            Append (Args, ",");
230         end loop;
231
232         Match (Line, Rem_Prn, "");
233         Append (Args, ')');
234      end if;
235
236      Must (Match (Line, Get_Rtn));
237
238      if Present (Inlined, Name) then
239         Put_Line (Ofile, A & "INLINE " & Rtn & ' ' & Name & Args & Term);
240      else
241         Put_Line (Ofile, A &  Rtn & ' ' & Name & Args & Term);
242      end if;
243   end Sethead;
244
245--  Start of processing for XEinfo
246
247begin
248   --  First run CEinfo to check for errors. Note that CEinfo is also a
249   --  stand-alone program that can be run separately.
250
251   CEinfo;
252
253   Anchored_Mode := True;
254
255   if Argument_Count > 0 then
256      Create (Ofile, Out_File, Argument (1));
257   else
258      Create (Ofile, Out_File, "einfo.h");
259   end if;
260
261   Open (InB, In_File, "einfo.adb");
262   Open (InF, In_File, "einfo.ads");
263
264   Lineno := 0;
265   loop
266      Line := Get_Line (InF);
267      Lineno := Lineno + 1;
268      exit when Line = "";
269
270      Match (Line,
271             "--                                 S p e c       ",
272             "--                              C Header File    ");
273      Match (Line, "--", "/*");
274      Match (Line, Rtab (2) * A & "--", M);
275      Replace (M, A & "*/");
276      Put_Line (Ofile, Line);
277   end loop;
278
279   Put_Line (Ofile, "");
280
281   Put_Line (Ofile, "#ifdef __cplusplus");
282   Put_Line (Ofile, "extern ""C"" {");
283   Put_Line (Ofile, "#endif");
284
285   --  Find and record pragma Inlines
286
287   loop
288      Line := Get_Line (InF);
289      exit when Match (Line, "   --  END XEINFO INLINES");
290
291      if Match (Line, Inline) then
292         Set (Inlined, Name, True);
293      end if;
294   end loop;
295
296   --  Skip to package line
297
298   Reset (InF, In_File);
299   Lineno := 0;
300
301   loop
302      Line := Getlin;
303      exit when Match (Line, Get_Pack);
304   end loop;
305
306   V := 0;
307   Line := Getlin;
308   Must (Match (Line, wsp & "type Entity_Kind"));
309
310   --  Process entity kind code definitions
311
312   loop
313      Line := Getlin;
314      exit when not Match (Line, Get_Enam);
315      Put_Line (Ofile, "   #define " & Rpad (N, 32) & " " & V);
316      V := V + 1;
317   end loop;
318
319   Must (Match (Line, wsp & Rest * N));
320   Put_Line (Ofile, "   #define " & Rpad (N, 32) & ' ' & V);
321   Line := Getlin;
322
323   Must (Match (Line, wsp & ");"));
324   Put_Line (Ofile, "");
325
326   --  Loop through subtype and type declarations
327
328   loop
329      Line := Getlin;
330      exit when Match (Line, Find_Fun);
331
332      --  Case of a subtype declaration
333
334      if Match (Line, F_Subtyp) then
335
336         --  Case of a subtype declaration that is an abbreviation of the
337         --  form subtype x is y, and if so generate the appropriate typedef
338
339         if Match (Line, G_Subtyp) then
340            Put_Line (Ofile, A & "typedef " & OldS & ' ' & NewS & ';');
341
342         --  Otherwise the subtype must be declaring a subrange of Entity_Id
343
344         else
345            Must (Match (Line, Get_Styp));
346            Line := Getlin;
347            Must (Match (Line, Get_N1));
348
349            loop
350               Line := Get_Line (InF);
351               Lineno := Lineno + 1;
352               exit when not Match (Line, Get_N2);
353            end loop;
354
355            Must (Match (Line, Get_N3));
356            Put_Line (Ofile, A & "SUBTYPE (" & N & ", Entity_Kind, ");
357            Put_Line (Ofile, A & "   " & N1 & ", " & N3 & ')');
358            Put_Line (Ofile, "");
359         end if;
360
361      --  Case of type declaration
362
363      elsif Match (Line, F_Typ) then
364
365         --  Process type declaration (must be enumeration type)
366
367         Ctr := 0;
368         Put_Line (Ofile, A & "typedef char " & N & ';');
369
370         loop
371            Line := Getlin;
372            Must (Match (Line, Get_Nam));
373            Put_Line (Ofile, A & "#define " & Rpad (Nam, 25) & Ctr);
374            Ctr := Ctr + 1;
375            exit when Term /= ",";
376         end loop;
377
378         Put_Line (Ofile, "");
379
380      --  Neither subtype nor type declaration
381
382      else
383         raise Err;
384      end if;
385   end loop;
386
387   --  Process function declarations
388
389   --  Note: Lastinlined used to control blank lines
390
391   Put_Line (Ofile, "");
392   Lastinlined := True;
393
394   --  Loop through function declarations
395
396   while Match (Line, Get_FN) loop
397
398      --  Non-inlined function
399
400      if not Present (Inlined, FN) then
401         Put_Line (Ofile, "");
402         Put_Line
403           (Ofile,
404            "   #define " & FN & " einfo__" & Translate (FN, Lower_Case_Map));
405
406      --  Inlined function
407
408      else
409         if not Lastinlined then
410            Put_Line (Ofile, "");
411         end if;
412      end if;
413
414      --  Merge here to output spec
415
416      Sethead (Line, ";");
417      Lastinlined := Get (Inlined, FN);
418      Line := Getlin;
419   end loop;
420
421   Put_Line (Ofile, "");
422
423   --  Read body to find inlined functions
424
425   Close (InB);
426   Close (InF);
427   Open (InF, In_File, "einfo.adb");
428   Lineno := 0;
429
430   --  Loop through input lines to find bodies of inlined functions
431
432   while not End_Of_File (InF) loop
433      Fline := Get_Line (InF);
434
435      if Match (Fline, Get_FN)
436        and then Get (Inlined, FN)
437      then
438         --  Here we have an inlined function
439
440         if not Match (Fline, Is_Rturn) then
441            Line := Fline;
442            Badfunc;
443         end if;
444
445         Line := Getlin;
446
447         if not Match (Line, Is_Begin) then
448            Badfunc;
449         end if;
450
451         --  Skip past pragma Asserts
452
453         loop
454            Line := Getlin;
455            exit when not Match (Line, Get_Asrt);
456
457            --  Pragma assert found, get its continuation lines
458
459            loop
460               exit when Match (Line, Semicoln);
461               Line := Getlin;
462            end loop;
463         end loop;
464
465         --  Process return statement
466
467         Match (Line, Get_Cmnt, M);
468         Replace (M, A);
469
470         --  Get continuations of return statement
471
472         while not Match (Line, Semicoln) loop
473            Nextlin := Getlin;
474            Match (Nextlin, wsp, " ");
475            Append (Line, Nextlin);
476         end loop;
477
478         if not Match (Line, Get_Expr) then
479            Badfunc;
480         end if;
481
482         Line := Getlin;
483
484         if not Match (Line, Chek_End) then
485            Badfunc;
486         end if;
487
488         Match (Expr, Get_B1, M);
489         Replace (M, "IN (" & A & ", " & B & ')');
490         Match (Expr, Get_B2, M);
491         Replace (M, A & " == " & B);
492         Match (Expr, Get_B3, M);
493         Replace (M, A & " != " & B);
494         Match (Expr, Get_B4, M);
495         Replace (M, A & " || " & B);
496         Put_Line (Ofile, "");
497         Sethead (Fline, "");
498         Put_Line (Ofile, C & "   { return " & Expr & "; }");
499      end if;
500   end loop;
501
502   Put_Line (Ofile, "");
503
504   Put_Line (Ofile, "#ifdef __cplusplus");
505   Put_Line (Ofile, "}");
506   Put_Line (Ofile, "#endif");
507
508   Put_Line
509     (Ofile,
510      "/* End of einfo.h (C version of Einfo package specification) */");
511
512   Close (InF);
513   Close (Ofile);
514
515exception
516   when Err =>
517      Put_Line (Standard_Error, Lineno & ".  " & Line);
518      Put_Line (Standard_Error, "**** fatal error ****");
519      Set_Exit_Status (1);
520
521   when End_Error =>
522      Put_Line (Standard_Error, "unexpected end of file");
523      Put_Line (Standard_Error, "**** fatal error ****");
524
525end XEinfo;
526