src/doc.c

   1 /* Record indices of function doc strings stored in a file.
   2    Copyright (C) 1985, 1986, 1992 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 #ifndef O_RDONLY
  31 #define O_RDONLY 0
  32 #endif
  33
  34 #include "lisp.h"
  35 #include "buffer.h"
  36 #include "keyboard.h"
  37
  38 Lisp_Object Vdoc_file_name;
  39
  40 Lisp_Object
  41 get_doc_string (filepos)
  42      long filepos;
  43 {
  44   char buf[512 * 32 + 1];
  45   register int fd;
  46   register char *name;
  47   register char *p, *p1;
  48   register int count;
  49   extern char *index ();
  50
  51   if (XTYPE (Vdata_directory) != Lisp_String
  52       || XTYPE (Vdoc_file_name) != Lisp_String)
  53     return Qnil;
  54
  55   name = (char *) alloca (XSTRING (Vdata_directory)->size
  56                           + XSTRING (Vdoc_file_name)->size + 8);
  57   strcpy (name, XSTRING (Vdata_directory)->data);
  58   strcat (name, XSTRING (Vdoc_file_name)->data);
  59 #ifdef VMS
  60 #ifndef VMS4_4
  61   /* For VMS versions with limited file name syntax,
  62      convert the name to something VMS will allow.  */
  63   p = name;
  64   while (*p)
  65     {
  66       if (*p == '-')
  67         *p = '_';
  68       p++;
  69     }
  70 #endif /* not VMS4_4 */
  71 #ifdef VMS4_4
  72   strcpy (name, sys_translate_unix (name));
  73 #endif /* VMS4_4 */
  74 #endif /* VMS */
  75
  76   fd = open (name, O_RDONLY, 0);
  77   if (fd < 0)
  78     error ("Cannot open doc string file \"%s\"", name);
  79   if (0 > lseek (fd, filepos, 0))
  80     {
  81       close (fd);
  82       error ("Position %ld out of range in doc string file \"%s\"",
  83              filepos, name);
  84     }
  85   p = buf;
  86   while (p != buf + sizeof buf - 1)
  87     {
  88       count = read (fd, p, 512);
  89       p[count] = 0;
  90       if (!count)
  91         break;
  92       p1 = index (p, '\037');
  93       if (p1)
  94         {
  95           *p1 = 0;
  96           p = p1;
  97           break;
  98         }
  99       p += count;
 100     }
 101   close (fd);
 102   return make_string (buf, p - buf);
 103 }
 104
 105 DEFUN ("documentation", Fdocumentation, Sdocumentation, 1, 2, 0,
 106   "Return the documentation string of FUNCTION.\n\
 107 Unless a non-nil second argument is given, the\n\
 108 string is passed through `substitute-command-keys'.")
 109   (function, raw)
 110      Lisp_Object function, raw;
 111 {
 112   Lisp_Object fun;
 113   Lisp_Object funcar;
 114   Lisp_Object tem, doc;
 115
 116   fun = Findirect_function (function);
 117
 118   switch (XTYPE (fun))
 119     {
 120     case Lisp_Subr:
 121       if (XSUBR (fun)->doc == 0) return Qnil;
 122       if ((int) XSUBR (fun)->doc >= 0)
 123         doc = build_string (XSUBR (fun)->doc);
 124       else
 125         doc = get_doc_string (- (int) XSUBR (fun)->doc);
 126       break;
 127
 128     case Lisp_Compiled:
 129       if (XVECTOR (fun)->size <= COMPILED_DOC_STRING)
 130         return Qnil;
 131       tem = XVECTOR (fun)->contents[COMPILED_DOC_STRING];
 132       if (XTYPE (tem) == Lisp_String)
 133         doc = tem;
 134       else if (XTYPE (tem) == Lisp_Int && XINT (tem) >= 0)
 135         doc = get_doc_string (XFASTINT (tem));
 136       else
 137         return Qnil;
 138       break;
 139
 140     case Lisp_String:
 141     case Lisp_Vector:
 142       return build_string ("Keyboard macro.");
 143
 144     case Lisp_Cons:
 145       funcar = Fcar (fun);
 146       if (XTYPE (funcar) != Lisp_Symbol)
 147         return Fsignal (Qinvalid_function, Fcons (fun, Qnil));
 148       else if (EQ (funcar, Qkeymap))
 149         return build_string ("Prefix command (definition is a keymap associating keystrokes with\n\
 150 subcommands.)");
 151       else if (EQ (funcar, Qlambda)
 152                || EQ (funcar, Qautoload))
 153         {
 154           tem = Fcar (Fcdr (Fcdr (fun)));
 155           if (XTYPE (tem) == Lisp_String)
 156             doc = tem;
 157           else if (XTYPE (tem) == Lisp_Int && XINT (tem) >= 0)
 158             doc = get_doc_string (XFASTINT (tem));
 159           else
 160             return Qnil;
 161
 162           break;
 163         }
 164       else if (EQ (funcar, Qmocklisp))
 165         return Qnil;
 166       else if (EQ (funcar, Qmacro))
 167         return Fdocumentation (Fcdr (fun), raw);
 168
 169       /* Fall through to the default to report an error.  */
 170
 171     default:
 172       return Fsignal (Qinvalid_function, Fcons (fun, Qnil));
 173     }
 174
 175   if (NILP (raw))
 176     {
 177       struct gcpro gcpro1;
 178
 179       GCPRO1 (doc);
 180       doc = Fsubstitute_command_keys (doc);
 181       UNGCPRO;
 182     }
 183   return doc;
 184 }
 185
 186 DEFUN ("documentation-property", Fdocumentation_property, Sdocumentation_property, 2, 2, 0,
 187   "Return the documentation string that is SYMBOL's PROP property.\n\
 188 This is like `get', but it can refer to strings stored in the\n\
 189 `etc/DOC' file; and if the value is a string, it is passed through\n\
 190 `substitute-command-keys'.  A non-nil third argument avoids this\n\
 191 translation.")
 192   (sym, prop, raw)
 193      Lisp_Object sym, prop, raw;
 194 {
 195   register Lisp_Object tem;
 196
 197   tem = Fget (sym, prop);
 198   if (XTYPE (tem) == Lisp_Int)
 199     tem = get_doc_string (XINT (tem) > 0 ? XINT (tem) : - XINT (tem));
 200   if (NILP (raw) && XTYPE (tem) == Lisp_String)
 201     return Fsubstitute_command_keys (tem);
 202   return tem;
 203 }
 204 \f
 205 DEFUN ("Snarf-documentation", Fsnarf_documentation, Ssnarf_documentation,
 206   1, 1, 0,
 207   "Used during Emacs initialization, before dumping runnable Emacs,\n\
 208 to find pointers to doc strings stored in `etc/DOC...' and\n\
 209 record them in function definitions.\n\
 210 One arg, FILENAME, a string which does not include a directory.\n\
 211 The file is found in `../etc' now; found in the `data-directory'\n\
 212 when doc strings are referred to later in the dumped Emacs.")
 213   (filename)
 214      Lisp_Object filename;
 215 {
 216   int fd;
 217   char buf[1024 + 1];
 218   register int filled;
 219   register int pos;
 220   register char *p, *end;
 221   Lisp_Object sym, fun, tem;
 222   char *name;
 223   extern char *index ();
 224
 225 #ifndef CANNOT_DUMP
 226   if (NILP (Vpurify_flag))
 227     error ("Snarf-documentation can only be called in an undumped Emacs");
 228 #endif
 229
 230   CHECK_STRING (filename, 0);
 231
 232 #ifndef CANNOT_DUMP
 233   name = (char *) alloca (XSTRING (filename)->size + 14);
 234   strcpy (name, "../etc/");
 235 #else /* CANNOT_DUMP */
 236   CHECK_STRING (Vdata_directory, 0);
 237   name = (char *) alloca (XSTRING (filename)->size +
 238                           XSTRING (Vdata_directory)->size + 1);
 239   strcpy (name, XSTRING (Vdata_directory)->data);
 240 #endif /* CANNOT_DUMP */
 241   strcat (name, XSTRING (filename)->data);      /*** Add this line ***/
 242 #ifdef VMS
 243 #ifndef VMS4_4
 244   /* For VMS versions with limited file name syntax,
 245      convert the name to something VMS will allow.  */
 246   p = name;
 247   while (*p)
 248     {
 249       if (*p == '-')
 250         *p = '_';
 251       p++;
 252     }
 253 #endif /* not VMS4_4 */
 254 #ifdef VMS4_4
 255   strcpy (name, sys_translate_unix (name));
 256 #endif /* VMS4_4 */
 257 #endif /* VMS */
 258
 259   fd = open (name, O_RDONLY, 0);
 260   if (fd < 0)
 261     report_file_error ("Opening doc string file",
 262                        Fcons (build_string (name), Qnil));
 263   Vdoc_file_name = filename;
 264   filled = 0;
 265   pos = 0;
 266   while (1)
 267     {
 268       if (filled < 512)
 269         filled += read (fd, &buf[filled], sizeof buf - 1 - filled);
 270       if (!filled)
 271         break;
 272
 273       buf[filled] = 0;
 274       p = buf;
 275       end = buf + (filled < 512 ? filled : filled - 128);
 276       while (p != end && *p != '\037') p++;
 277       /* p points to ^_Ffunctionname\n or ^_Vvarname\n.  */
 278       if (p != end)
 279         {
 280           end = index (p, '\n');
 281           sym = oblookup (Vobarray, p + 2, end - p - 2);
 282           if (XTYPE (sym) == Lisp_Symbol)
 283             {
 284               /* Attach a docstring to a variable?  */
 285               if (p[1] == 'V')
 286                 {
 287                   /* Install file-position as variable-documentation property
 288                      and make it negative for a user-variable
 289                      (doc starts with a `*').  */
 290                   Fput (sym, Qvariable_documentation,
 291                         make_number ((pos + end + 1 - buf)
 292                                      * (end[1] == '*' ? -1 : 1)));
 293                 }
 294
 295               /* Attach a docstring to a function?  The type determines where
 296                  the docstring is stored.  */
 297               else if (p[1] == 'F')
 298                 {
 299                   fun = XSYMBOL (sym)->function;
 300
 301                   /* Lisp_Subrs have a slot for it.  */
 302                   if (XTYPE (fun) == Lisp_Subr)
 303                     XSUBR (fun)->doc = (char *) - (pos + end + 1 - buf);
 304
 305                   /* If it's a lisp form, stick it in the form.  */
 306                   else if (CONSP (fun))
 307                     {
 308                       tem = XCONS (fun)->car;
 309                       if (EQ (tem, Qlambda) || EQ (tem, Qautoload))
 310                         {
 311                           tem = Fcdr (Fcdr (fun));
 312                           if (CONSP (tem) &&
 313                               XTYPE (XCONS (tem)->car) == Lisp_Int)
 314                             XFASTINT (XCONS (tem)->car) = (pos + end + 1 - buf);
 315                         }
 316                     }
 317
 318                   /* Bytecode objects sometimes have slots for it.  */
 319                   else if (XTYPE (fun) == Lisp_Compiled)
 320                     {
 321                       /* This bytecode object must have a slot for the
 322                          docstring, since we've found a docstring for it.  */
 323                       if (XVECTOR (fun)->size <= COMPILED_DOC_STRING)
 324                         abort ();
 325
 326                       XFASTINT (XVECTOR (fun)->contents[COMPILED_DOC_STRING])
 327                         = pos + end + 1 - buf;
 328                     }
 329                 }
 330               else error ("DOC file invalid at position %d", pos);
 331             }
 332         }
 333       pos += end - buf;
 334       filled -= end - buf;
 335       bcopy (end, buf, filled);
 336     }
 337   close (fd);
 338   return Qnil;
 339 }
 340 \f
 341 DEFUN ("substitute-command-keys", Fsubstitute_command_keys,
 342   Ssubstitute_command_keys, 1, 1, 0,
 343   "Substitute key descriptions for command names in STRING.\n\
 344 Return a new string which is STRING with substrings of the form \\=\\[COMMAND]\n\
 345 replaced by either:  a keystroke sequence that will invoke COMMAND,\n\
 346 or \"M-x COMMAND\" if COMMAND is not on any keys.\n\
 347 Substrings of the form \\=\\{MAPVAR} are replaced by summaries\n\
 348 \(made by describe-bindings) of the value of MAPVAR, taken as a keymap.\n\
 349 Substrings of the form \\=\\<MAPVAR> specify to use the value of MAPVAR\n\
 350 as the keymap for future \\=\\[COMMAND] substrings.\n\
 351 \\=\\= quotes the following character and is discarded;\n\
 352 thus, \\=\\=\\=\\= puts \\=\\= into the output, and \\=\\=\\=\\[ puts \\=\\[ into the output.")
 353   (str)
 354      Lisp_Object str;
 355 {
 356   unsigned char *buf;
 357   int changed = 0;
 358   register unsigned char *strp;
 359   register unsigned char *bufp;
 360   int idx;
 361   int bsize;
 362   unsigned char *new;
 363   Lisp_Object tem;
 364   Lisp_Object keymap;
 365   unsigned char *start;
 366   int length;
 367   Lisp_Object name;
 368   struct gcpro gcpro1, gcpro2, gcpro3, gcpro4;
 369
 370   if (NILP (str))
 371     return Qnil;
 372
 373   CHECK_STRING (str, 0);
 374   tem = Qnil;
 375   keymap = Qnil;
 376   name = Qnil;
 377   GCPRO4 (str, tem, keymap, name);
 378
 379   keymap = current_buffer->keymap;
 380
 381   bsize = XSTRING (str)->size;
 382   bufp = buf = (unsigned char *) xmalloc (bsize);
 383
 384   strp = (unsigned char *) XSTRING (str)->data;
 385   while (strp < (unsigned char *) XSTRING (str)->data + XSTRING (str)->size)
 386     {
 387       if (strp[0] == '\\' && strp[1] == '=')
 388         {
 389           /* \= quotes the next character;
 390              thus, to put in \[ without its special meaning, use \=\[.  */
 391           changed = 1;
 392           *bufp++ = strp[2];
 393           strp += 3;
 394         }
 395       else if (strp[0] == '\\' && strp[1] == '[')
 396         {
 397           changed = 1;
 398           strp += 2;            /* skip \[ */
 399           start = strp;
 400
 401           while ((strp - (unsigned char *) XSTRING (str)->data
 402                   < XSTRING (str)->size)
 403                  && *strp != ']')
 404             strp++;
 405           length = strp - start;
 406           strp++;               /* skip ] */
 407
 408           /* Save STRP in IDX.  */
 409           idx = strp - (unsigned char *) XSTRING (str)->data;
 410           tem = Fintern (make_string (start, length), Qnil);
 411           tem = Fwhere_is_internal (tem, keymap, Qnil, Qt, Qnil);
 412
 413           if (NILP (tem))       /* but not on any keys */
 414             {
 415               new = (unsigned char *) xrealloc (buf, bsize += 4);
 416               bufp += new - buf;
 417               buf = new;
 418               bcopy ("M-x ", bufp, 4);
 419               bufp += 4;
 420               goto subst;
 421             }
 422           else
 423             {                   /* function is on a key */
 424               tem = Fkey_description (tem);
 425               goto subst_string;
 426             }
 427         }
 428       /* \{foo} is replaced with a summary of the keymap (symbol-value foo).
 429          \<foo> just sets the keymap used for \[cmd].  */
 430       else if (strp[0] == '\\' && (strp[1] == '{' || strp[1] == '<'))
 431         {
 432           struct buffer *oldbuf;
 433
 434           changed = 1;
 435           strp += 2;            /* skip \{ or \< */
 436           start = strp;
 437
 438           while ((strp - (unsigned char *) XSTRING (str)->data
 439                   < XSTRING (str)->size)
 440                  && *strp != '}' && *strp != '>')
 441             strp++;
 442           length = strp - start;
 443           strp++;                       /* skip } or > */
 444
 445           /* Save STRP in IDX.  */
 446           idx = strp - (unsigned char *) XSTRING (str)->data;
 447
 448           /* Get the value of the keymap in TEM, or nil if undefined.
 449              Do this while still in the user's current buffer
 450              in case it is a local variable.  */
 451           name = Fintern (make_string (start, length), Qnil);
 452           tem = Fboundp (name);
 453           if (! NILP (tem))
 454             {
 455               tem = Fsymbol_value (name);
 456               if (! NILP (tem))
 457                 tem = get_keymap_1 (tem, 0, 1);
 458             }
 459
 460           /* Now switch to a temp buffer.  */
 461           oldbuf = current_buffer;
 462           set_buffer_internal (XBUFFER (Vprin1_to_string_buffer));
 463
 464           if (NILP (tem))
 465             {
 466               name = Fsymbol_name (name);
 467               insert_string ("\nUses keymap \"");
 468               insert_from_string (name, 0, XSTRING (name)->size);
 469               insert_string ("\", which is not currently defined.\n");
 470               if (start[-1] == '<') keymap = Qnil;
 471             }
 472           else if (start[-1] == '<')
 473             keymap = tem;
 474           else
 475             describe_map_tree (tem, 1, Qnil);
 476           tem = Fbuffer_string ();
 477           Ferase_buffer ();
 478           set_buffer_internal (oldbuf);
 479
 480         subst_string:
 481           start = XSTRING (tem)->data;
 482           length = XSTRING (tem)->size;
 483         subst:
 484           new = (unsigned char *) xrealloc (buf, bsize += length);
 485           bufp += new - buf;
 486           buf = new;
 487           bcopy (start, bufp, length);
 488           bufp += length;
 489           /* Check STR again in case gc relocated it.  */
 490           strp = (unsigned char *) XSTRING (str)->data + idx;
 491         }
 492       else                      /* just copy other chars */
 493         *bufp++ = *strp++;
 494     }
 495
 496   if (changed)                  /* don't bother if nothing substituted */
 497     tem = make_string (buf, bufp - buf);
 498   else
 499     tem = str;
 500   free (buf);
 501   RETURN_UNGCPRO (tem);
 502 }
 503 \f
 504 syms_of_doc ()
 505 {
 506   DEFVAR_LISP ("internal-doc-file-name", &Vdoc_file_name,
 507     "Name of file containing documentation strings of built-in symbols.");
 508   Vdoc_file_name = Qnil;
 509
 510   defsubr (&Sdocumentation);
 511   defsubr (&Sdocumentation_property);
 512   defsubr (&Ssnarf_documentation);
 513   defsubr (&Ssubstitute_command_keys);
 514 }