gdb/command.c

   1 /* Library for reading command lines and decoding commands.
   2    Copyright (C) 1986 Free Software Foundation, Inc.
   3
   4                        NO WARRANTY
   5
   6   BECAUSE THIS PROGRAM IS LICENSED FREE OF CHARGE, WE PROVIDE ABSOLUTELY
   7 NO WARRANTY, TO THE EXTENT PERMITTED BY APPLICABLE STATE LAW.  EXCEPT
   8 WHEN OTHERWISE STATED IN WRITING, FREE SOFTWARE FOUNDATION, INC,
   9 RICHARD M. STALLMAN AND/OR OTHER PARTIES PROVIDE THIS PROGRAM "AS IS"
  10 WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
  11 BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  12 FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY
  13 AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE PROGRAM PROVE
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  16
  17  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW WILL RICHARD M.
  18 STALLMAN, THE FREE SOFTWARE FOUNDATION, INC., AND/OR ANY OTHER PARTY
  19 WHO MAY MODIFY AND REDISTRIBUTE THIS PROGRAM AS PERMITTED BELOW, BE
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  27
  28                 GENERAL PUBLIC LICENSE TO COPY
  29
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  33 (C) 1986 Free Software Foundation, Inc."; and include following the
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  53     transferring a copy, and you may at your option offer warranty
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  60   3. You may copy and distribute this program (or a portion or derivative
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  84   4. You may not copy, sublicense, distribute or transfer this program
  85 except as expressly provided under this License Agreement.  Any attempt
  86 otherwise to copy, sublicense, distribute or transfer this program is void and
  87 your rights to use the program under this License agreement shall be
  88 automatically terminated.  However, parties who have received computer
  89 software programs from you with this License Agreement will not have
  90 their licenses terminated so long as such parties remain in full compliance.
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  92   5. If you wish to incorporate parts of this program into other free
  93 programs whose distribution conditions are different, write to the Free
  94 Software Foundation at 675 Mass Ave, Cambridge, MA 02139.  We have not yet
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  99
 100
 101 In other words, you are welcome to use, share and improve this program.
 102 You are forbidden to forbid anyone else to use, share and improve
 103 what you give them.   Help stamp out software-hoarding!  */
 104
 105
 106 #include "command.h"
 107 #include <stdio.h>
 108
 109 #ifdef sparc
 110 #include <alloca.h>
 111 #endif
 112
 113 extern char *xmalloc ();
 114
 115 static char *savestring ();
 116
 117 /* Add element named NAME to command list *LIST.
 118    FUN should be the function to execute the command;
 119    it will get a character string as argument, with leading
 120    and trailing blanks already eliminated.
 121
 122    DOC is a documentation string for the command.
 123    Its first line should be a complete sentence.
 124    It should start with ? for a command that is an abbreviation
 125    or with * for a command that most users don't need to know about.  */
 126
 127 struct cmd_list_element *
 128 add_cmd (name, class, fun, doc, list)
 129      char *name;
 130      int class;
 131      void (*fun) ();
 132      char *doc;
 133      struct cmd_list_element **list;
 134 {
 135   register struct cmd_list_element *c
 136     = (struct cmd_list_element *) xmalloc (sizeof (struct cmd_list_element));
 137
 138   delete_cmd (name, list);
 139   c->next = *list;
 140   c->name = savestring (name, strlen (name));
 141   c->class = class;
 142   c->function = fun;
 143   c->doc = doc;
 144   c->prefixlist = 0;
 145   c->allow_unknown = 0;
 146   c->abbrev_flag = 0;
 147   c->aux = 0;
 148   *list = c;
 149   return c;
 150 }
 151
 152 struct cmd_list_element *
 153 add_alias_cmd (name, oldname, class, abbrev_flag, list)
 154      char *name;
 155      char *oldname;
 156      int class;
 157      int abbrev_flag;
 158      struct cmd_list_element **list;
 159 {
 160   /* Must do this since lookup_cmd tries to side-effect its first arg */
 161   char *copied_name;
 162   register struct cmd_list_element *old;
 163   register struct cmd_list_element *c;
 164   copied_name = (char *) alloca (strlen (oldname) + 1);
 165   strcpy (copied_name, oldname);
 166   old  = lookup_cmd (&copied_name, *list, 0, 1);
 167
 168   if (old == 0)
 169     {
 170       delete_cmd (name, list);
 171       return 0;
 172     }
 173
 174   c = add_cmd (name, class, old->function, old->doc, list);
 175   c->prefixlist = old->prefixlist;
 176   c->prefixname = old->prefixname;
 177   c->allow_unknown = old->allow_unknown;
 178   c->abbrev_flag = abbrev_flag;
 179   c->aux = old->aux;
 180   return c;
 181 }
 182
 183 /* Like add_prefix_cmd but adds an element for a command prefix:
 184    a name that should be followed by a subcommand to be looked up
 185    in another command list.  PREFIXLIST should be the address
 186    of the variable containing that list.  */
 187
 188 struct cmd_list_element *
 189 add_prefix_cmd (name, class, fun, doc, prefixlist, prefixname,
 190                 allow_unknown, list)
 191      char *name;
 192      int class;
 193      void (*fun) ();
 194      char *doc;
 195      struct cmd_list_element **prefixlist;
 196      char *prefixname;
 197      int allow_unknown;
 198      struct cmd_list_element **list;
 199 {
 200   register struct cmd_list_element *c = add_cmd (name, class, fun, doc, list);
 201   c->prefixlist = prefixlist;
 202   c->prefixname = prefixname;
 203   c->allow_unknown = allow_unknown;
 204   return c;
 205 }
 206
 207 /* Remove the command named NAME from the command list.  */
 208
 209 void
 210 delete_cmd (name, list)
 211      char *name;
 212      struct cmd_list_element **list;
 213 {
 214   register struct cmd_list_element *c;
 215
 216   while (*list && !strcmp ((*list)->name, name))
 217     {
 218       *list = (*list)->next;
 219     }
 220
 221   if (*list)
 222     for (c = *list; c->next;)
 223       {
 224         if (!strcmp (c->next->name, name))
 225           c->next = c->next->next;
 226         else
 227           c = c->next;
 228       }
 229 }
 230
 231 /* Implement a help command on command list LIST.
 232    COMMAND is the argument given (a command from the list to document)
 233    or zero for no arg (describe briefly all the commands in the list).
 234    CMDTYPE is a string to use in the error message if command COMMAND
 235    is not found in the list.  */
 236
 237 /* CLASS should be -1 to list all commands in LIST,
 238    or a nonnegative class number value to list just commands in that class,
 239    or -2 to list the classes themselves.  */
 240
 241 void
 242 help_cmd (command, list, cmdtype, class, stream)
 243      char *command;
 244      struct cmd_list_element *list;
 245      char *cmdtype;
 246      int class;
 247      FILE *stream;
 248 {
 249   register struct cmd_list_element *c;
 250   register char *p;
 251   register int ncmds;
 252   struct cmdvec { struct cmd_list_element *cmd; int class; };
 253   register struct cmdvec *cmdvec;
 254   char *cmdtype1, *cmdtype2;
 255   int len;
 256
 257   if (command)
 258     {
 259       c = lookup_cmd (&command, list, cmdtype, 0);
 260       if (c == 0)
 261         return;
 262
 263       /* There are three cases here.
 264          If c->prefixlist is nonzer, we have a prefix command.
 265          Print its documentation, then list its subcommands.
 266
 267          If c->function is nonzero, we really have a command.
 268          Print its documentation and return.
 269
 270          If c->function is zero, we have a class name.
 271          Print its documentation (as if it were a command)
 272          and then set class to he number of this class
 273          so that the commands in the class will be listed.  */
 274
 275       p = c->doc;
 276       fprintf (stream, "%s\n", p);
 277       if (c->function != 0 && c->prefixlist == 0)
 278         return;
 279       fputc ('\n', stream);
 280       if (c->prefixlist)
 281         {
 282           list = *c->prefixlist;
 283           class = 0;
 284           cmdtype = c->prefixname;
 285         }
 286       else
 287         class = c->class;
 288     }
 289
 290   /* If CMDTYPE is "foo ", CMDTYPE1 gets " foo" and CMDTYPE2 gets "foo sub"  */
 291   len = strlen (cmdtype);
 292   cmdtype1 = (char *) alloca (len + 1);
 293   cmdtype1[0] = 0;
 294   cmdtype2 = (char *) alloca (len + 4);
 295   cmdtype2[0] = 0;
 296   if (len)
 297     {
 298       cmdtype1[0] = ' ';
 299       strncpy (cmdtype1 + 1, cmdtype, len - 1);
 300       cmdtype1[len] = 0;
 301       strncpy (cmdtype2, cmdtype, len - 1);
 302       strcpy (cmdtype2 + len - 1, " sub");
 303     }
 304
 305   if (class == -2)
 306     fprintf (stream, "List of classes of %scommands:\n\n", cmdtype2);
 307   else
 308     fprintf (stream, "List of %scommands:\n\n", cmdtype2);
 309
 310   for (c = list; c; c = c->next)
 311     {
 312       if (c->abbrev_flag == 0
 313           && (class == -1       /* Listing all */
 314               || (c->class == class && c->function != 0) /* Listing one class */
 315               || (class == -2 && c->function == 0)))    /* Listing the classes */
 316         {
 317           fprintf (stream, "%s -- ", c->name);
 318           /* Print just first line of documentation.  */
 319           p = c->doc;
 320           while (*p && *p != '\n') p++;
 321           fwrite (c->doc, 1, p - c->doc, stream);
 322           fputc ('\n', stream);
 323         }
 324     }
 325
 326   if (class == -2)
 327     fprintf (stream, "\n\
 328 Type \"help%s\" followed by a class name for a list of commands in that class.",
 329              cmdtype1);
 330
 331   fprintf (stream, "\n\
 332 Type \"help%s\" followed by %scommand name for full documentation.\n\
 333 Command name abbreviations are allowed if unambiguous.\n",
 334            cmdtype1, cmdtype2);
 335 }
 336 \f
 337 /* Look up the contents of *LINE as a command in the command list LIST.
 338    LIST is a chain of struct cmd_list_element's.
 339    If it is found, return the struct cmd_list_element for that command
 340    and update *LINE to point after the command name, at the first argument.
 341    If not found, call error if ALLOW_UNKNOWN is zero
 342    otherwise (or if error returns) return zero.
 343    Call error if specified command is ambiguous,
 344    unless ALLOW_UNKNOWN is negative.
 345    CMDTYPE precedes the word "command" in the error message.  */
 346
 347 struct cmd_list_element *
 348 lookup_cmd (line, list, cmdtype, allow_unknown)
 349      char **line;
 350      struct cmd_list_element *list;
 351      char *cmdtype;
 352      int allow_unknown;
 353 {
 354   register char *p;
 355   register struct cmd_list_element *c, *found;
 356   int nfound;
 357   char ambbuf[100];
 358
 359   /* Skip leading whitespace.  */
 360
 361   while (**line == ' ' || **line == '\t')
 362     (*line)++;
 363
 364   /* Clear out trailing whitespace.  */
 365
 366   p = *line + strlen (*line);
 367   while (p != *line && (p[-1] == ' ' || p[-1] == '\t'))
 368     p--;
 369   *p = 0;
 370
 371   /* Find end of command name.  */
 372
 373   p = *line;
 374   while (*p == '-'
 375          || (*p >= 'a' && *p <= 'z')
 376          || (*p >= 'A' && *p <= 'Z')
 377          || (*p >= '0' && *p <= '9'))
 378     {
 379       if (*p >= 'A' && *p <= 'Z')
 380         *p += 'a' - 'A';
 381       p++;
 382     }
 383
 384   /* Look up the command name.
 385      If exact match, keep that.
 386      Otherwise, take command abbreviated, if unique.  */
 387
 388   found = 0;
 389   nfound = 0;
 390   for (c = list; c; c = c->next)
 391     {
 392       if (!strncmp (*line, c->name, p - *line))
 393         {
 394           found = c;
 395           nfound++;
 396           if (c->name[p - *line] == 0)
 397             {
 398               nfound = 1;
 399               break;
 400             }
 401         }
 402     }
 403
 404   /* Report error for undefined command name.  */
 405
 406   if (nfound != 1)
 407     {
 408       if (nfound > 1 && allow_unknown >= 0)
 409         {
 410           *p = 0;
 411           ambbuf[0] = 0;
 412           for (c = list; c; c = c->next)
 413             if (!strncmp (*line, c->name, p - *line))
 414               {
 415                 if (strlen (ambbuf) + strlen (c->name) + 6 < sizeof ambbuf)
 416                   {
 417                     if (strlen (ambbuf))
 418                       strcat (ambbuf, ", ");
 419                     strcat (ambbuf, c->name);
 420                   }
 421                 else
 422                   {
 423                     strcat (ambbuf, "..");
 424                     break;
 425                   }
 426               }
 427           error ("Ambiguous %scommand \"%s\": %s.", cmdtype, *line, ambbuf);
 428         }
 429       else if (!allow_unknown)
 430         {
 431           *p = 0;
 432           error ("Undefined %scommand: \"%s\".", cmdtype, *line);
 433         }
 434       return 0;
 435     }
 436
 437   /* Skip whitespace before the argument.  */
 438
 439   while (*p == ' ' || *p == '\t') p++;
 440   *line = p;
 441
 442   if (found->prefixlist && *p)
 443     {
 444       c = lookup_cmd (line, *found->prefixlist, found->prefixname,
 445                       found->allow_unknown);
 446       if (c)
 447         return c;
 448     }
 449
 450   return found;
 451 }
 452
 453 /* Make a copy of the string at PTR with SIZE characters
 454    (and add a null character at the end in the copy).
 455    Uses malloc to get the space.  Returns the address of the copy.  */
 456
 457 static char *
 458 savestring (ptr, size)
 459      char *ptr;
 460      int size;
 461 {
 462   register char *p = (char *) xmalloc (size + 1);
 463   bcopy (ptr, p, size);
 464   p[size] = 0;
 465   return p;
 466 }