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 ((EMACS_INT) XSUBR (fun)->doc >= 0)
 129         doc = build_string (XSUBR (fun)->doc);
 130       else
 131         doc = get_doc_string (- (EMACS_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         XFASTINT (XVECTOR (fun)->contents[COMPILED_DOC_STRING]) = offset;
 250     }
 251 }
 252
 253
 254 DEFUN ("Snarf-documentation", Fsnarf_documentation, Ssnarf_documentation,
 255   1, 1, 0,
 256   "Used during Emacs initialization, before dumping runnable Emacs,\n\
 257 to find pointers to doc strings stored in `etc/DOC...' and\n\
 258 record them in function definitions.\n\
 259 One arg, FILENAME, a string which does not include a directory.\n\
 260 The file is found in `../etc' now; found in the `data-directory'\n\
 261 when doc strings are referred to later in the dumped Emacs.")
 262   (filename)
 263      Lisp_Object filename;
 264 {
 265   int fd;
 266   char buf[1024 + 1];
 267   register int filled;
 268   register int pos;
 269   register char *p, *end;
 270   Lisp_Object sym, fun, tem;
 271   char *name;
 272   extern char *index ();
 273
 274 #ifndef CANNOT_DUMP
 275   if (NILP (Vpurify_flag))
 276     error ("Snarf-documentation can only be called in an undumped Emacs");
 277 #endif
 278
 279   CHECK_STRING (filename, 0);
 280
 281 #ifndef CANNOT_DUMP
 282   name = (char *) alloca (XSTRING (filename)->size + 14);
 283   strcpy (name, "../etc/");
 284 #else /* CANNOT_DUMP */
 285   CHECK_STRING (Vdoc_directory, 0);
 286   name = (char *) alloca (XSTRING (filename)->size +
 287                           XSTRING (Vdoc_directory)->size + 1);
 288   strcpy (name, XSTRING (Vdoc_directory)->data);
 289 #endif /* CANNOT_DUMP */
 290   strcat (name, XSTRING (filename)->data);      /*** Add this line ***/
 291 #ifdef VMS
 292 #ifndef VMS4_4
 293   /* For VMS versions with limited file name syntax,
 294      convert the name to something VMS will allow.  */
 295   p = name;
 296   while (*p)
 297     {
 298       if (*p == '-')
 299         *p = '_';
 300       p++;
 301     }
 302 #endif /* not VMS4_4 */
 303 #ifdef VMS4_4
 304   strcpy (name, sys_translate_unix (name));
 305 #endif /* VMS4_4 */
 306 #endif /* VMS */
 307
 308   fd = open (name, O_RDONLY, 0);
 309   if (fd < 0)
 310     report_file_error ("Opening doc string file",
 311                        Fcons (build_string (name), Qnil));
 312   Vdoc_file_name = filename;
 313   filled = 0;
 314   pos = 0;
 315   while (1)
 316     {
 317       if (filled < 512)
 318         filled += read (fd, &buf[filled], sizeof buf - 1 - filled);
 319       if (!filled)
 320         break;
 321
 322       buf[filled] = 0;
 323       p = buf;
 324       end = buf + (filled < 512 ? filled : filled - 128);
 325       while (p != end && *p != '\037') p++;
 326       /* p points to ^_Ffunctionname\n or ^_Vvarname\n.  */
 327       if (p != end)
 328         {
 329           end = index (p, '\n');
 330           sym = oblookup (Vobarray, p + 2, end - p - 2);
 331           if (XTYPE (sym) == Lisp_Symbol)
 332             {
 333               /* Attach a docstring to a variable?  */
 334               if (p[1] == 'V')
 335                 {
 336                   /* Install file-position as variable-documentation property
 337                      and make it negative for a user-variable
 338                      (doc starts with a `*').  */
 339                   Fput (sym, Qvariable_documentation,
 340                         make_number ((pos + end + 1 - buf)
 341                                      * (end[1] == '*' ? -1 : 1)));
 342                 }
 343
 344               /* Attach a docstring to a function?  */
 345               else if (p[1] == 'F')
 346                 store_function_docstring (sym, pos + end + 1 - buf);
 347
 348               else
 349                 error ("DOC file invalid at position %d", pos);
 350             }
 351         }
 352       pos += end - buf;
 353       filled -= end - buf;
 354       bcopy (end, buf, filled);
 355     }
 356   close (fd);
 357   return Qnil;
 358 }
 359 \f
 360 DEFUN ("substitute-command-keys", Fsubstitute_command_keys,
 361   Ssubstitute_command_keys, 1, 1, 0,
 362   "Substitute key descriptions for command names in STRING.\n\
 363 Return a new string which is STRING with substrings of the form \\=\\[COMMAND]\n\
 364 replaced by either:  a keystroke sequence that will invoke COMMAND,\n\
 365 or \"M-x COMMAND\" if COMMAND is not on any keys.\n\
 366 Substrings of the form \\=\\{MAPVAR} are replaced by summaries\n\
 367 \(made by describe-bindings) of the value of MAPVAR, taken as a keymap.\n\
 368 Substrings of the form \\=\\<MAPVAR> specify to use the value of MAPVAR\n\
 369 as the keymap for future \\=\\[COMMAND] substrings.\n\
 370 \\=\\= quotes the following character and is discarded;\n\
 371 thus, \\=\\=\\=\\= puts \\=\\= into the output, and \\=\\=\\=\\[ puts \\=\\[ into the output.")
 372   (str)
 373      Lisp_Object str;
 374 {
 375   unsigned char *buf;
 376   int changed = 0;
 377   register unsigned char *strp;
 378   register unsigned char *bufp;
 379   int idx;
 380   int bsize;
 381   unsigned char *new;
 382   Lisp_Object tem;
 383   Lisp_Object keymap;
 384   unsigned char *start;
 385   int length;
 386   Lisp_Object name;
 387   struct gcpro gcpro1, gcpro2, gcpro3, gcpro4;
 388
 389   if (NILP (str))
 390     return Qnil;
 391
 392   CHECK_STRING (str, 0);
 393   tem = Qnil;
 394   keymap = Qnil;
 395   name = Qnil;
 396   GCPRO4 (str, tem, keymap, name);
 397
 398   /* KEYMAP is either nil (which means search all the active keymaps)
 399      or a specified local map (which means search just that and the
 400      global map).  If non-nil, it might come from Voverriding_local_map,
 401      or from a \\<mapname> construct in STR itself..  */
 402   keymap = Voverriding_local_map;
 403
 404   bsize = XSTRING (str)->size;
 405   bufp = buf = (unsigned char *) xmalloc (bsize);
 406
 407   strp = (unsigned char *) XSTRING (str)->data;
 408   while (strp < (unsigned char *) XSTRING (str)->data + XSTRING (str)->size)
 409     {
 410       if (strp[0] == '\\' && strp[1] == '=')
 411         {
 412           /* \= quotes the next character;
 413              thus, to put in \[ without its special meaning, use \=\[.  */
 414           changed = 1;
 415           *bufp++ = strp[2];
 416           strp += 3;
 417         }
 418       else if (strp[0] == '\\' && strp[1] == '[')
 419         {
 420           Lisp_Object firstkey;
 421
 422           changed = 1;
 423           strp += 2;            /* skip \[ */
 424           start = strp;
 425
 426           while ((strp - (unsigned char *) XSTRING (str)->data
 427                   < XSTRING (str)->size)
 428                  && *strp != ']')
 429             strp++;
 430           length = strp - start;
 431           strp++;               /* skip ] */
 432
 433           /* Save STRP in IDX.  */
 434           idx = strp - (unsigned char *) XSTRING (str)->data;
 435           tem = Fintern (make_string (start, length), Qnil);
 436           tem = Fwhere_is_internal (tem, keymap, Qt, Qnil);
 437
 438           /* Disregard menu bar bindings; it is positively annoying to
 439              mention them when there's no menu bar, and it isn't terribly
 440              useful even when there is a menu bar.  */
 441           if (!NILP (tem))
 442             {
 443               firstkey = Faref (tem, make_number (0));
 444               if (EQ (firstkey, Qmenu_bar))
 445                 tem = Qnil;
 446             }
 447
 448           if (NILP (tem))       /* but not on any keys */
 449             {
 450               new = (unsigned char *) xrealloc (buf, bsize += 4);
 451               bufp += new - buf;
 452               buf = new;
 453               bcopy ("M-x ", bufp, 4);
 454               bufp += 4;
 455               goto subst;
 456             }
 457           else
 458             {                   /* function is on a key */
 459               tem = Fkey_description (tem);
 460               goto subst_string;
 461             }
 462         }
 463       /* \{foo} is replaced with a summary of the keymap (symbol-value foo).
 464          \<foo> just sets the keymap used for \[cmd].  */
 465       else if (strp[0] == '\\' && (strp[1] == '{' || strp[1] == '<'))
 466         {
 467           struct buffer *oldbuf;
 468
 469           changed = 1;
 470           strp += 2;            /* skip \{ or \< */
 471           start = strp;
 472
 473           while ((strp - (unsigned char *) XSTRING (str)->data
 474                   < XSTRING (str)->size)
 475                  && *strp != '}' && *strp != '>')
 476             strp++;
 477           length = strp - start;
 478           strp++;                       /* skip } or > */
 479
 480           /* Save STRP in IDX.  */
 481           idx = strp - (unsigned char *) XSTRING (str)->data;
 482
 483           /* Get the value of the keymap in TEM, or nil if undefined.
 484              Do this while still in the user's current buffer
 485              in case it is a local variable.  */
 486           name = Fintern (make_string (start, length), Qnil);
 487           tem = Fboundp (name);
 488           if (! NILP (tem))
 489             {
 490               tem = Fsymbol_value (name);
 491               if (! NILP (tem))
 492                 tem = get_keymap_1 (tem, 0, 1);
 493             }
 494
 495           /* Now switch to a temp buffer.  */
 496           oldbuf = current_buffer;
 497           set_buffer_internal (XBUFFER (Vprin1_to_string_buffer));
 498
 499           if (NILP (tem))
 500             {
 501               name = Fsymbol_name (name);
 502               insert_string ("\nUses keymap \"");
 503               insert_from_string (name, 0, XSTRING (name)->size, 1);
 504               insert_string ("\", which is not currently defined.\n");
 505               if (start[-1] == '<') keymap = Qnil;
 506             }
 507           else if (start[-1] == '<')
 508             keymap = tem;
 509           else
 510             describe_map_tree (tem, 1, Qnil, Qnil, 0, 1);
 511           tem = Fbuffer_string ();
 512           Ferase_buffer ();
 513           set_buffer_internal (oldbuf);
 514
 515         subst_string:
 516           start = XSTRING (tem)->data;
 517           length = XSTRING (tem)->size;
 518         subst:
 519           new = (unsigned char *) xrealloc (buf, bsize += length);
 520           bufp += new - buf;
 521           buf = new;
 522           bcopy (start, bufp, length);
 523           bufp += length;
 524           /* Check STR again in case gc relocated it.  */
 525           strp = (unsigned char *) XSTRING (str)->data + idx;
 526         }
 527       else                      /* just copy other chars */
 528         *bufp++ = *strp++;
 529     }
 530
 531   if (changed)                  /* don't bother if nothing substituted */
 532     tem = make_string (buf, bufp - buf);
 533   else
 534     tem = str;
 535   xfree (buf);
 536   RETURN_UNGCPRO (tem);
 537 }
 538 \f
 539 syms_of_doc ()
 540 {
 541   DEFVAR_LISP ("internal-doc-file-name", &Vdoc_file_name,
 542     "Name of file containing documentation strings of built-in symbols.");
 543   Vdoc_file_name = Qnil;
 544
 545   defsubr (&Sdocumentation);
 546   defsubr (&Sdocumentation_property);
 547   defsubr (&Ssnarf_documentation);
 548   defsubr (&Ssubstitute_command_keys);
 549 }