command.c

早期freebsd实现

/* Handle lists of commands, their decoding and documentation, for GDB.
   Copyright 1986, 1989, 1990, 1991 Free Software Foundation, Inc.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#include "defs.h"
#include "gdbcmd.h"
#include "symtab.h"
#include "value.h"
#include <ctype.h>
#include <string.h>

/* Prototypes for local functions */

static void
undef_cmd_error PARAMS ((char *, char *));

static void
show_user PARAMS ((char *, int));

static void
show_user_1 PARAMS ((struct cmd_list_element *, FILE *));

static void
make_command PARAMS ((char *, int));

static void
shell_escape PARAMS ((char *, int));

static int
parse_binary_operation PARAMS ((char *));

static void
print_doc_line PARAMS ((FILE *, char *));

/* Add element named NAME to command list *LIST.
   FUN should be the function to execute the command;
   it will get a character string as argument, with leading
   and trailing blanks already eliminated.

   DOC is a documentation string for the command.
   Its first line should be a complete sentence.
   It should start with ? for a command that is an abbreviation
   or with * for a command that most users don't need to know about.  */

struct cmd_list_element *
add_cmd (name, class, fun, doc, list)
     char *name;
     enum command_class class;
     void (*fun) PARAMS ((char *, int));
     char *doc;
     struct cmd_list_element **list;
{
  register struct cmd_list_element *c
    = (struct cmd_list_element *) xmalloc (sizeof (struct cmd_list_element));

  delete_cmd (name, list);
  c->next = *list;
  c->name = name;
  c->class = class;
  c->function.cfunc = fun;
  c->doc = doc;
  c->prefixlist = 0;
  c->prefixname = (char *)NULL;
  c->allow_unknown = 0;
  c->hook = 0;
  c->hookee = 0;
  c->cmd_pointer = 0;
  c->abbrev_flag = 0;
  c->type = not_set_cmd;
  c->completer = make_symbol_completion_list;
  c->var = 0;
  c->var_type = var_boolean;
  c->user_commands = 0;
  *list = c;
  return c;
}

/* Same as above, except that the abbrev_flag is set. */

#if 0	/* Currently unused */

struct cmd_list_element *
add_abbrev_cmd (name, class, fun, doc, list)
     char *name;
     enum command_class class;
     void (*fun) PARAMS ((char *, int));
     char *doc;
     struct cmd_list_element **list;
{
  register struct cmd_list_element *c
    = add_cmd (name, class, fun, doc, list);

  c->abbrev_flag = 1;
  return c;
}

#endif

struct cmd_list_element *
add_alias_cmd (name, oldname, class, abbrev_flag, list)
     char *name;
     char *oldname;
     enum command_class class;
     int abbrev_flag;
     struct cmd_list_element **list;
{
  /* Must do this since lookup_cmd tries to side-effect its first arg */
  char *copied_name;
  register struct cmd_list_element *old;
  register struct cmd_list_element *c;
  copied_name = (char *) alloca (strlen (oldname) + 1);
  strcpy (copied_name, oldname);
  old  = lookup_cmd (&copied_name, *list, "", 1, 1);

  if (old == 0)
    {
      delete_cmd (name, list);
      return 0;
    }

  c = add_cmd (name, class, old->function.cfunc, old->doc, list);
  c->prefixlist = old->prefixlist;
  c->prefixname = old->prefixname;
  c->allow_unknown = old->allow_unknown;
  c->abbrev_flag = abbrev_flag;
  c->cmd_pointer = old;
  return c;
}

/* Like add_cmd but adds an element for a command prefix:
   a name that should be followed by a subcommand to be looked up
   in another command list.  PREFIXLIST should be the address
   of the variable containing that list.  */

struct cmd_list_element *
add_prefix_cmd (name, class, fun, doc, prefixlist, prefixname,
		allow_unknown, list)
     char *name;
     enum command_class class;
     void (*fun) PARAMS ((char *, int));
     char *doc;
     struct cmd_list_element **prefixlist;
     char *prefixname;
     int allow_unknown;
     struct cmd_list_element **list;
{
  register struct cmd_list_element *c = add_cmd (name, class, fun, doc, list);
  c->prefixlist = prefixlist;
  c->prefixname = prefixname;
  c->allow_unknown = allow_unknown;
  return c;
}

/* Like add_prefix_cmd but sets the abbrev_flag on the new command. */
   
struct cmd_list_element *
add_abbrev_prefix_cmd (name, class, fun, doc, prefixlist, prefixname,
		       allow_unknown, list)
     char *name;
     enum command_class class;
     void (*fun) PARAMS ((char *, int));
     char *doc;
     struct cmd_list_element **prefixlist;
     char *prefixname;
     int allow_unknown;
     struct cmd_list_element **list;
{
  register struct cmd_list_element *c = add_cmd (name, class, fun, doc, list);
  c->prefixlist = prefixlist;
  c->prefixname = prefixname;
  c->allow_unknown = allow_unknown;
  c->abbrev_flag = 1;
  return c;
}

/* ARGSUSED */
void
not_just_help_class_command (args, from_tty)
     char *args;
     int from_tty;
{
}

/* Add element named NAME to command list LIST (the list for set
   or some sublist thereof).
   CLASS is as in add_cmd.
   VAR_TYPE is the kind of thing we are setting.
   VAR is address of the variable being controlled by this command.
   DOC is the documentation string.  */

struct cmd_list_element *
add_set_cmd (name, class, var_type, var, doc, list)
     char *name;
     enum command_class class;
     var_types var_type;
     char *var;
     char *doc;
     struct cmd_list_element **list;
{
  /* For set/show, we have to call do_setshow_command
     differently than an ordinary function (take commandlist as
     well as arg), so the function field isn't helpful.  However,
     function == NULL means that it's a help class, so set the function
     to not_just_help_class_command.  */
  struct cmd_list_element *c
    = add_cmd (name, class, not_just_help_class_command, doc, list);

  c->type = set_cmd;
  c->var_type = var_type;
  c->var = var;
  return c;
}

/* Where SETCMD has already been added, add the corresponding show
   command to LIST and return a pointer to it.  */
struct cmd_list_element *
add_show_from_set (setcmd, list)
     struct cmd_list_element *setcmd;
     struct cmd_list_element **list;
{
  struct cmd_list_element *showcmd =
    (struct cmd_list_element *) xmalloc (sizeof (struct cmd_list_element));

  memcpy (showcmd, setcmd, sizeof (struct cmd_list_element));
  delete_cmd (showcmd->name, list);
  showcmd->type = show_cmd;
  
  /* Replace "set " at start of docstring with "show ".  */
  if (setcmd->doc[0] == 'S' && setcmd->doc[1] == 'e'
      && setcmd->doc[2] == 't' && setcmd->doc[3] == ' ')
    showcmd->doc = concat ("Show ", setcmd->doc + 4, NULL);
  else
    fprintf (stderr, "GDB internal error: Bad docstring for set command\n");
  
  showcmd->next = *list;
  *list = showcmd;
  return showcmd;
}

/* Remove the command named NAME from the command list.  */

void
delete_cmd (name, list)
     char *name;
     struct cmd_list_element **list;
{
  register struct cmd_list_element *c;
  struct cmd_list_element *p;

  while (*list && !strcmp ((*list)->name, name))
    {
      if ((*list)->hookee)
	(*list)->hookee->hook = 0;	/* Hook slips out of its mouth */
      p = (*list)->next;
      free ((PTR)*list);
      *list = p;
    }

  if (*list)
    for (c = *list; c->next;)
      {
	if (!strcmp (c->next->name, name))
	  {
	    if (c->next->hookee)
	      c->next->hookee->hook = 0;  /* hooked cmd gets away.  */
	    p = c->next->next;
	    free ((PTR)c->next);
	    c->next = p;
	  }
	else
	  c = c->next;
      }
}

/* This command really has to deal with two things:
 *     1) I want documentation on *this string* (usually called by
 * "help commandname").
 *     2) I want documentation on *this list* (usually called by
 * giving a command that requires subcommands.  Also called by saying
 * just "help".)
 *
 *   I am going to split this into two seperate comamnds, help_cmd and
 * help_list. 
 */

void
help_cmd (command, stream)
     char *command;
     FILE *stream;
{
  struct cmd_list_element *c;
  extern struct cmd_list_element *cmdlist;

  if (!command)
    {
      help_list (cmdlist, "", all_classes, stream);
      return;
    }

  c = lookup_cmd (&command, cmdlist, "", 0, 0);

  if (c == 0)
    return;

  /* There are three cases here.
     If c->prefixlist is nonzero, we have a prefix command.
     Print its documentation, then list its subcommands.
     
     If c->function is nonzero, we really have a command.
     Print its documentation and return.
     
     If c->function is zero, we have a class name.
     Print its documentation (as if it were a command)
     and then set class to the number of this class
     so that the commands in the class will be listed.  */

  fputs_filtered (c->doc, stream);
  fputs_filtered ("\n", stream);

  if (c->prefixlist == 0 && c->function.cfunc != NULL)
    return;
  fprintf_filtered (stream, "\n");

  /* If this is a prefix command, print it's subcommands */
  if (c->prefixlist)
    help_list (*c->prefixlist, c->prefixname, all_commands, stream);

  /* If this is a class name, print all of the commands in the class */
  if (c->function.cfunc == NULL)
    help_list (cmdlist, "", c->class, stream);

  if (c->hook)
    fprintf_filtered (stream, "\nThis command has a hook defined: %s\n",
		      c->hook->name);
}

/*
 * Get a specific kind of help on a command list.
 *
 * LIST is the list.
 * CMDTYPE is the prefix to use in the title string.
 * CLASS is the class with which to list the nodes of this list (see
 * documentation for help_cmd_list below),  As usual, ALL_COMMANDS for
 * everything, ALL_CLASSES for just classes, and non-negative for only things
 * in a specific class.
 * and STREAM is the output stream on which to print things.
 * If you call this routine with a class >= 0, it recurses.
 */
void
help_list (list, cmdtype, class, stream)
     struct cmd_list_element *list;
     char *cmdtype;
     enum command_class class;
     FILE *stream;
{
  int len;
  char *cmdtype1, *cmdtype2;
  
  /* If CMDTYPE is "foo ", CMDTYPE1 gets " foo" and CMDTYPE2 gets "foo sub"  */
  len = strlen (cmdtype);
  cmdtype1 = (char *) alloca (len + 1);
  cmdtype1[0] = 0;
  cmdtype2 = (char *) alloca (len + 4);
  cmdtype2[0] = 0;
  if (len)
    {
      cmdtype1[0] = ' ';
      strncpy (cmdtype1 + 1, cmdtype, len - 1);
      cmdtype1[len] = 0;
      strncpy (cmdtype2, cmdtype, len - 1);
      strcpy (cmdtype2 + len - 1, " sub");
    }

  if (class == all_classes)
    fprintf_filtered (stream, "List of classes of %scommands:\n\n", cmdtype2);
  else
    fprintf_filtered (stream, "List of %scommands:\n\n", cmdtype2);

  help_cmd_list (list, class, cmdtype, (int)class >= 0, stream);

  if (class == all_classes)
    fprintf_filtered (stream, "\n\
Type \"help%s\" followed by a class name for a list of commands in that class.",
	     cmdtype1);

  fprintf_filtered (stream, "\n\
Type \"help%s\" followed by %scommand name for full documentation.\n\
Command name abbreviations are allowed if unambiguous.\n",
	   cmdtype1, cmdtype2);
}
     
/* Print only the first line of STR on STREAM.  */
static void
print_doc_line (stream, str)
     FILE *stream;
     char *str;
{
  static char *line_buffer = 0;
  static int line_size;
  register char *p;

  if (!line_buffer)
    {
      line_size = 80;
      line_buffer = (char *) xmalloc (line_size);