src/doc.c

   1 /* Record indices of function doc strings stored in a file.
   2    Copyright (C) 1985, 1986, 1993, 1994 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 1, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20
  21 #include <config.h>
  22
  23 #include <sys/types.h>
  24 #include <sys/file.h>   /* Must be after sys/types.h for USG and BSD4_1*/
  25
  26 #ifdef USG5
  27 #include <fcntl.h>
  28 #endif
  29
  30 #ifdef HAVE_UNISTD_H
  31 #include <unistd.h>
  32 #endif
  33
  34 #ifndef O_RDONLY
  35 #define O_RDONLY 0
  36 #endif
  37
  38 #include "lisp.h"
  39 #include "buffer.h"
  40 #include "keyboard.h"
  41
  42 Lisp_Object Vdoc_file_name;
  43
  44 extern Lisp_Object Voverriding_local_map;
  45
  46 Lisp_Object
  47 get_doc_string (filepos)
  48      long filepos;
  49 {
  50   char buf[512 * 32 + 1];
  51   register int fd;
  52   register char *name;
  53   register char *p, *p1;
  54   register int count;
  55   extern char *index ();
  56
  57   if (XTYPE (Vdoc_directory) != Lisp_String
  58       || XTYPE (Vdoc_file_name) != Lisp_String)
  59     return Qnil;
  60
  61   name = (char *) alloca (XSTRING (Vdoc_directory)->size
  62                           + XSTRING (Vdoc_file_name)->size + 8);
  63   strcpy (name, XSTRING (Vdoc_directory)->data);
  64   strcat (name, XSTRING (Vdoc_file_name)->data);
  65 #ifdef VMS
  66 #ifndef VMS4_4
  67   /* For VMS versions with limited file name syntax,
  68      convert the name to something VMS will allow.  */
  69   p = name;
  70   while (*p)
  71     {
  72       if (*p == '-')
  73         *p = '_';
  74       p++;
  75     }
  76 #endif /* not VMS4_4 */
  77 #ifdef VMS4_4
  78   strcpy (name, sys_translate_unix (name));
  79 #endif /* VMS4_4 */
  80 #endif /* VMS */
  81
  82   fd = open (name, O_RDONLY, 0);
  83   if (fd < 0)
  84     error ("Cannot open doc string file \"%s\"", name);
  85   if (0 > lseek (fd, filepos, 0))
  86     {
  87       close (fd);
  88       error ("Position %ld out of range in doc string file \"%s\"",
  89              filepos, name);
  90     }
  91   p = buf;
  92   while (p != buf + sizeof buf - 1)
  93     {
  94       count = read (fd, p, 512);
  95       p[count] = 0;
  96       if (!count)
  97         break;
  98       p1 = index (p, '\037');
  99       if (p1)
 100         {
 101           *p1 = 0;
 102           p = p1;
 103           break;
 104         }
 105       p += count;
 106     }
 107   close (fd);
 108   return make_string (buf, p - buf);
 109 }
 110
 111 DEFUN ("documentation", Fdocumentation, Sdocumentation, 1, 2, 0,
 112   "Return the documentation string of FUNCTION.\n\
 113 Unless a non-nil second argument is given, the\n\
 114 string is passed through `substitute-command-keys'.")
 115   (function, raw)
 116      Lisp_Object function, raw;
 117 {
 118   Lisp_Object fun;
 119   Lisp_Object funcar;
 120   Lisp_Object tem, doc;
 121
 122   fun = Findirect_function (function);
 123
 124   switch (XTYPE (fun))
 125     {
 126     case Lisp_Subr:
 127       if (XSUBR (fun)->doc == 0) return Qnil;
 128       if ((int) XSUBR (fun)->doc >= 0)
 129         doc = build_string (XSUBR (fun)->doc);
 130       else
 131         doc = get_doc_string (- (int) XSUBR (fun)->doc);
 132       break;
 133
 134     case Lisp_Compiled:
 135       if (XVECTOR (fun)->size <= COMPILED_DOC_STRING)
 136         return Qnil;
 137       tem = XVECTOR (fun)->contents[COMPILED_DOC_STRING];
 138       if (XTYPE (tem) == Lisp_String)
 139         doc = tem;
 140       else if (XTYPE (tem) == Lisp_Int && XINT (tem) >= 0)
 141         doc = get_doc_string (XFASTINT (tem));
 142       else
 143         return Qnil;
 144       break;
 145
 146     case Lisp_String:
 147     case Lisp_Vector:
 148       return build_string ("Keyboard macro.");
 149
 150     case Lisp_Cons:
 151       funcar = Fcar (fun);
 152       if (XTYPE (funcar) != Lisp_Symbol)
 153         return Fsignal (Qinvalid_function, Fcons (fun, Qnil));
 154       else if (EQ (funcar, Qkeymap))
 155         return build_string ("Prefix command (definition is a keymap associating keystrokes with\n\
 156 subcommands.)");
 157       else if (EQ (funcar, Qlambda)
 158                || EQ (funcar, Qautoload))
 159         {
 160           tem = Fcar (Fcdr (Fcdr (fun)));
 161           if (XTYPE (tem) == Lisp_String)
 162             doc = tem;
 163           else if (XTYPE (tem) == Lisp_Int && XINT (tem) >= 0)
 164             doc = get_doc_string (XFASTINT (tem));
 165           else
 166             return Qnil;
 167
 168           break;
 169         }
 170       else if (EQ (funcar, Qmocklisp))
 171         return Qnil;
 172       else if (EQ (funcar, Qmacro))
 173         return Fdocumentation (Fcdr (fun), raw);
 174
 175       /* Fall through to the default to report an error.  */
 176
 177     default:
 178       return Fsignal (Qinvalid_function, Fcons (fun, Qnil));
 179     }
 180
 181   if (NILP (raw))
 182     {
 183       struct gcpro gcpro1;
 184
 185       GCPRO1 (doc);
 186       doc = Fsubstitute_command_keys (doc);
 187       UNGCPRO;
 188     }
 189   return doc;
 190 }
 191
 192 DEFUN ("documentation-property", Fdocumentation_property, Sdocumentation_property, 2, 3, 0,
 193   "Return the documentation string that is SYMBOL's PROP property.\n\
 194 This is like `get', but it can refer to strings stored in the\n\
 195 `etc/DOC' file; and if the value is a string, it is passed through\n\
 196 `substitute-command-keys'.  A non-nil third argument avoids this\n\
 197 translation.")
 198   (sym, prop, raw)
 199      Lisp_Object sym, prop, raw;
 200 {
 201   register Lisp_Object tem;
 202
 203   tem = Fget (sym, prop);
 204   if (XTYPE (tem) == Lisp_Int)
 205     tem = get_doc_string (XINT (tem) > 0 ? XINT (tem) : - XINT (tem));
 206   if (NILP (raw) && XTYPE (tem) == Lisp_String)
 207     return Fsubstitute_command_keys (tem);
 208   return tem;
 209 }
 210 \f
 211 /* Scanning the DOC files and placing docstring offsets into functions.  */
 212
 213 static void
 214 store_function_docstring (fun, offset)
 215      Lisp_Object fun;
 216      int offset;
 217 {
 218   fun = indirect_function (fun);
 219
 220   /* The type determines where the docstring is stored.  */
 221
 222   /* Lisp_Subrs have a slot for it.  */
 223   if (XTYPE (fun) == Lisp_Subr)
 224     XSUBR (fun)->doc = (char *) - offset;
 225
 226   /* If it's a lisp form, stick it in the form.  */
 227   else if (CONSP (fun))
 228     {
 229       Lisp_Object tem;
 230
 231       tem = XCONS (fun)->car;
 232       if (EQ (tem, Qlambda) || EQ (tem, Qautoload))
 233         {
 234           tem = Fcdr (Fcdr (fun));
 235           if (CONSP (tem) &&
 236               XTYPE (XCONS (tem)->car) == Lisp_Int)
 237             XFASTINT (XCONS (tem)->car) = offset;
 238         }
 239       else if (EQ (tem, Qmacro))
 240         store_function_docstring (XCONS (fun)->cdr, offset);
 241     }
 242
 243   /* Bytecode objects sometimes have slots for it.  */
 244   else if (XTYPE (fun) == Lisp_Compiled)
 245     {
 246       /* This bytecode object must have a slot for the
 247          docstring, since we've found a docstring for it.  */
 248       if (XVECTOR (fun)->size <= COMPILED_DOC_STRING)
 249         abort ();
 250
 251       XFASTINT (XVECTOR (fun)->contents[COMPILED_DOC_STRING]) = offset;
 252     }
 253 }
 254
 255
 256 DEFUN ("Snarf-documentation", Fsnarf_documentation, Ssnarf_documentation,
 257   1, 1, 0,
 258   "Used during Emacs initialization, before dumping runnable Emacs,\n\
 259 to find pointers to doc strings stored in `etc/DOC...' and\n\
 260 record them in function definitions.\n\
 261 One arg, FILENAME, a string which does not include a directory.\n\
 262 The file is found in `../etc' now; found in the `data-directory'\n\
 263 when doc strings are referred to later in the dumped Emacs.")
 264   (filename)
 265      Lisp_Object filename;
 266 {
 267   int fd;
 268   char buf[1024 + 1];
 269   register int filled;
 270   register int pos;
 271   register char *p, *end;
 272   Lisp_Object sym, fun, tem;
 273   char *name;
 274   extern char *index ();
 275
 276 #ifndef CANNOT_DUMP
 277   if (NILP (Vpurify_flag))
 278     error ("Snarf-documentation can only be called in an undumped Emacs");
 279 #endif
 280
 281   CHECK_STRING (filename, 0);
 282
 283 #ifndef CANNOT_DUMP
 284   name = (char *) alloca (XSTRING (filename)->size + 14);
 285   strcpy (name, "../etc/");
 286 #else /* CANNOT_DUMP */
 287   CHECK_STRING (Vdoc_directory, 0);
 288   name = (char *) alloca (XSTRING (filename)->size +
 289                           XSTRING (Vdoc_directory)->size + 1);
 290   strcpy (name, XSTRING (Vdoc_directory)->data);
 291 #endif /* CANNOT_DUMP */
 292   strcat (name, XSTRING (filename)->data);      /*** Add this line ***/
 293 #ifdef VMS
 294 #ifndef VMS4_4
 295   /* For VMS versions with limited file name syntax,
 296      convert the name to something VMS will allow.  */
 297   p = name;
 298   while (*p)
 299     {
 300       if (*p == '-')
 301         *p = '_';
 302       p++;
 303     }
 304 #endif /* not VMS4_4 */
 305 #ifdef VMS4_4
 306   strcpy (name, sys_translate_unix (name));
 307 #endif /* VMS4_4 */
 308 #endif /* VMS */
 309
 310   fd = open (name, O_RDONLY, 0);
 311   if (fd < 0)
 312     report_file_error ("Opening doc string file",
 313                        Fcons (build_string (name), Qnil));
 314   Vdoc_file_name = filename;
 315   filled = 0;
 316   pos = 0;
 317   while (1)
 318     {
 319       if (filled < 512)
 320         filled += read (fd, &buf[filled], sizeof buf - 1 - filled);
 321       if (!filled)
 322         break;
 323
 324       buf[filled] = 0;
 325       p = buf;
 326       end = buf + (filled < 512 ? filled : filled - 128);
 327       while (p != end && *p != '\037') p++;
 328       /* p points to ^_Ffunctionname\n or ^_Vvarname\n.  */
 329       if (p != end)
 330         {
 331           end = index (p, '\n');
 332           sym = oblookup (Vobarray, p + 2, end - p - 2);
 333           if (XTYPE (sym) == Lisp_Symbol)
 334             {
 335               /* Attach a docstring to a variable?  */
 336               if (p[1] == 'V')
 337                 {
 338                   /* Install file-position as variable-documentation property
 339                      and make it negative for a user-variable
 340                      (doc starts with a `*').  */
 341                   Fput (sym, Qvariable_documentation,
 342                         make_number ((pos + end + 1 - buf)
 343                                      * (end[1] == '*' ? -1 : 1)));
 344                 }
 345
 346               /* Attach a docstring to a function?  */
 347               else if (p[1] == 'F')
 348                 store_function_docstring (sym, pos + end + 1 - buf);
 349
 350               else
 351                 error ("DOC file invalid at position %d", pos);
 352             }
 353         }
 354       pos += end - buf;
 355       filled -= end - buf;
 356       bcopy (end, buf, filled);
 357     }
 358   close (fd);
 359   return Qnil;
 360 }
 361 \f
 362 DEFUN ("substitute-command-keys", Fsubstitute_command_keys,
 363   Ssubstitute_command_keys, 1, 1, 0,
 364   "Substitute key descriptions for command names in STRING.\n\
 365 Return a new string which is STRING with substrings of the form \\=\\[COMMAND]\n\
 366 replaced by either:  a keystroke sequence that will invoke COMMAND,\n\
 367 or \"M-x COMMAND\" if COMMAND is not on any keys.\n\
 368 Substrings of the form \\=\\{MAPVAR} are replaced by summaries\n\
 369 \(made by describe-bindings) of the value of MAPVAR, taken as a keymap.\n\
 370 Substrings of the form \\=\\<MAPVAR> specify to use the value of MAPVAR\n\
 371 as the keymap for future \\=\\[COMMAND] substrings.\n\
 372 \\=\\= quotes the following character and is discarded;\n\
 373 thus, \\=\\=\\=\\= puts \\=\\= into the output, and \\=\\=\\=\\[ puts \\=\\[ into the output.")
 374   (str)
 375      Lisp_Object str;
 376 {
 377   unsigned char *buf;
 378   int changed = 0;
 379   register unsigned char *strp;
 380   register unsigned char *bufp;
 381   int idx;
 382   int bsize;
 383   unsigned char *new;
 384   Lisp_Object tem;
 385   Lisp_Object keymap;
 386   unsigned char *start;
 387   int length;
 388   Lisp_Object name;
 389   struct gcpro gcpro1, gcpro2, gcpro3, gcpro4;
 390
 391   if (NILP (str))
 392     return Qnil;
 393
 394   CHECK_STRING (str, 0);
 395   tem = Qnil;
 396   keymap = Qnil;
 397   name = Qnil;
 398   GCPRO4 (str, tem, keymap, name);
 399
 400   /* KEYMAP is either nil (which means search all the active keymaps)
 401      or a specified local map (which means search just that and the
 402      global map).  If non-nil, it might come from Voverriding_local_map,
 403      or from a \\<mapname> construct in STR itself..  */
 404   keymap = Voverriding_local_map;
 405
 406   bsize = XSTRING (str)->size;
 407   bufp = buf = (unsigned char *) xmalloc (bsize);
 408
 409   strp = (unsigned char *) XSTRING (str)->data;
 410   while (strp < (unsigned char *) XSTRING (str)->data + XSTRING (str)->size)
 411     {
 412       if (strp[0] == '\\' && strp[1] == '=')
 413         {
 414           /* \= quotes the next character;
 415              thus, to put in \[ without its special meaning, use \=\[.  */
 416           changed = 1;
 417           *bufp++ = strp[2];
 418           strp += 3;
 419         }
 420       else if (strp[0] == '\\' && strp[1] == '[')
 421         {
 422           Lisp_Object firstkey;
 423
 424           changed = 1;
 425           strp += 2;            /* skip \[ */
 426           start = strp;
 427
 428           while ((strp - (unsigned char *) XSTRING (str)->data
 429                   < XSTRING (str)->size)
 430                  && *strp != ']')
 431             strp++;
 432           length = strp - start;
 433           strp++;               /* skip ] */
 434
 435           /* Save STRP in IDX.  */
 436           idx = strp - (unsigned char *) XSTRING (str)->data;
 437           tem = Fintern (make_string (start, length), Qnil);
 438           tem = Fwhere_is_internal (tem, keymap, Qt, Qnil);
 439
 440           /* Disregard menu bar bindings; it is positively annoying to
 441              mention them when there's no menu bar, and it isn't terribly
 442              useful even when there is a menu bar.  */
 443           if (!NILP (tem))
 444             {
 445               firstkey = Faref (tem, make_number (0));
 446               if (EQ (firstkey, Qmenu_bar))
 447                 tem = Qnil;
 448             }
 449
 450           if (NILP (tem))       /* but not on any keys */
 451             {
 452               new = (unsigned char *) xrealloc (buf, bsize += 4);
 453               bufp += new - buf;
 454               buf = new;
 455               bcopy ("M-x ", bufp, 4);
 456               bufp += 4;
 457               goto subst;
 458             }
 459           else
 460             {                   /* function is on a key */
 461               tem = Fkey_description (tem);
 462               goto subst_string;
 463             }
 464         }
 465       /* \{foo} is replaced with a summary of the keymap (symbol-value foo).
 466          \<foo> just sets the keymap used for \[cmd].  */
 467       else if (strp[0] == '\\' && (strp[1] == '{' || strp[1] == '<'))
 468         {
 469           struct buffer *oldbuf;
 470
 471           changed = 1;
 472           strp += 2;            /* skip \{ or \< */
 473           start = strp;
 474
 475           while ((strp - (unsigned char *) XSTRING (str)->data
 476                   < XSTRING (str)->size)
 477                  && *strp != '}' && *strp != '>')
 478             strp++;
 479           length = strp - start;
 480           strp++;                       /* skip } or > */
 481
 482           /* Save STRP in IDX.  */
 483           idx = strp - (unsigned char *) XSTRING (str)->data;
 484
 485           /* Get the value of the keymap in TEM, or nil if undefined.
 486              Do this while still in the user's current buffer
 487              in case it is a local variable.  */
 488           name = Fintern (make_string (start, length), Qnil);
 489           tem = Fboundp (name);
 490           if (! NILP (tem))
 491             {
 492               tem = Fsymbol_value (name);
 493               if (! NILP (tem))
 494                 tem = get_keymap_1 (tem, 0, 1);
 495             }
 496
 497           /* Now switch to a temp buffer.  */
 498           oldbuf = current_buffer;
 499           set_buffer_internal (XBUFFER (Vprin1_to_string_buffer));
 500
 501           if (NILP (tem))
 502             {
 503               name = Fsymbol_name (name);
 504               insert_string ("\nUses keymap \"");
 505               insert_from_string (name, 0, XSTRING (name)->size, 1);
 506               insert_string ("\", which is not currently defined.\n");
 507               if (start[-1] == '<') keymap = Qnil;
 508             }
 509           else if (start[-1] == '<')
 510             keymap = tem;
 511           else
 512             describe_map_tree (tem, 1, Qnil, Qnil, 0, 1);
 513           tem = Fbuffer_string ();
 514           Ferase_buffer ();
 515           set_buffer_internal (oldbuf);
 516
 517         subst_string:
 518           start = XSTRING (tem)->data;
 519           length = XSTRING (tem)->size;
 520         subst:
 521           new = (unsigned char *) xrealloc (buf, bsize += length);
 522           bufp += new - buf;
 523           buf = new;
 524           bcopy (start, bufp, length);
 525           bufp += length;
 526           /* Check STR again in case gc relocated it.  */
 527           strp = (unsigned char *) XSTRING (str)->data + idx;
 528         }
 529       else                      /* just copy other chars */
 530         *bufp++ = *strp++;
 531     }
 532
 533   if (changed)                  /* don't bother if nothing substituted */
 534     tem = make_string (buf, bufp - buf);
 535   else
 536     tem = str;
 537   xfree (buf);
 538   RETURN_UNGCPRO (tem);
 539 }
 540 \f
 541 syms_of_doc ()
 542 {
 543   DEFVAR_LISP ("internal-doc-file-name", &Vdoc_file_name,
 544     "Name of file containing documentation strings of built-in symbols.");
 545   Vdoc_file_name = Qnil;
 546
 547   defsubr (&Sdocumentation);
 548   defsubr (&Sdocumentation_property);
 549   defsubr (&Ssnarf_documentation);
 550   defsubr (&Ssubstitute_command_keys);
 551 }