/* MI Command Set - MI parser.

   Copyright (C) 2000-2013 Free Software Foundation, Inc.

   Contributed by Cygnus Solutions (a Red Hat company).

   This file is part of GDB.

   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 3 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, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"
#include "mi-cmds.h"
#include "mi-parse.h"
#include "charset.h"

#include <ctype.h>
#include "gdb_string.h"

/* Like parse_escape, but leave the results as a host char, not a
   target char.  */

static int
mi_parse_escape (char **string_ptr)
{
  int c = *(*string_ptr)++;

  switch (c)
    {
      case '\n':
	return -2;
      case 0:
	(*string_ptr)--;
	return 0;

      case '0':
      case '1':
      case '2':
      case '3':
      case '4':
      case '5':
      case '6':
      case '7':
	{
	  int i = host_hex_value (c);
	  int count = 0;

	  while (++count < 3)
	    {
	      c = (**string_ptr);
	      if (isdigit (c) && c != '8' && c != '9')
		{
		  (*string_ptr)++;
		  i *= 8;
		  i += host_hex_value (c);
		}
	      else
		{
		  break;
		}
	    }
	  return i;
	}

    case 'a':
      c = '\a';
      break;
    case 'b':
      c = '\b';
      break;
    case 'f':
      c = '\f';
      break;
    case 'n':
      c = '\n';
      break;
    case 'r':
      c = '\r';
      break;
    case 't':
      c = '\t';
      break;
    case 'v':
      c = '\v';
      break;

    default:
      break;
    }

  return c;
}

static void
mi_parse_argv (char *args, struct mi_parse *parse)
{
  char *chp = args;
  int argc = 0;
  char **argv = xmalloc ((argc + 1) * sizeof (char *));

  argv[argc] = NULL;
  while (1)
    {
      char *arg;

      /* Skip leading white space.  */
      while (isspace (*chp))
	chp++;
      /* Three possibilities: EOF, quoted string, or other text. */
      switch (*chp)
	{
	case '\0':
	  parse->argv = argv;
	  parse->argc = argc;
	  return;
	case '"':
	  {
	    /* A quoted string.  */
	    int len;
	    char *start = chp + 1;

	    /* Determine the buffer size.  */
	    chp = start;
	    len = 0;
	    while (*chp != '\0' && *chp != '"')
	      {
		if (*chp == '\\')
		  {
		    chp++;
		    if (mi_parse_escape (&chp) <= 0)
		      {
			/* Do not allow split lines or "\000".  */
			freeargv (argv);
			return;
		      }
		  }
		else
		  chp++;
		len++;
	      }
	    /* Insist on a closing quote.  */
	    if (*chp != '"')
	      {
		freeargv (argv);
		return;
	      }
	    /* Insist on trailing white space.  */
	    if (chp[1] != '\0' && !isspace (chp[1]))
	      {
		freeargv (argv);
		return;
	      }
	    /* Create the buffer and copy characters in.  */
	    arg = xmalloc ((len + 1) * sizeof (char));
	    chp = start;
	    len = 0;
	    while (*chp != '\0' && *chp != '"')
	      {
		if (*chp == '\\')
		  {
		    chp++;
		    arg[len] = mi_parse_escape (&chp);
		  }
		else
		  arg[len] = *chp++;
		len++;
	      }
	    arg[len] = '\0';
	    chp++;		/* That closing quote.  */
	    break;
	  }
	default:
	  {
	    /* An unquoted string.  Accumulate all non-blank
	       characters into a buffer.  */
	    int len;
	    char *start = chp;

	    while (*chp != '\0' && !isspace (*chp))
	      {
		chp++;
	      }
	    len = chp - start;
	    arg = xmalloc ((len + 1) * sizeof (char));
	    strncpy (arg, start, len);
	    arg[len] = '\0';
	    break;
	  }
	}
      /* Append arg to argv.  */
      argv = xrealloc (argv, (argc + 2) * sizeof (char *));
      argv[argc++] = arg;
      argv[argc] = NULL;
    }
}

void
mi_parse_free (struct mi_parse *parse)
{
  if (parse == NULL)
    return;
  if (parse->command != NULL)
    xfree (parse->command);
  if (parse->token != NULL)
    xfree (parse->token);
  if (parse->args != NULL)
    xfree (parse->args);
  if (parse->argv != NULL)
    freeargv (parse->argv);
  xfree (parse);
}

/* A cleanup that calls mi_parse_free.  */

static void
mi_parse_cleanup (void *arg)
{
  mi_parse_free (arg);
}

struct mi_parse *
mi_parse (char *cmd, char **token)
{
  char *chp;
  struct mi_parse *parse = XMALLOC (struct mi_parse);
  struct cleanup *cleanup;

  memset (parse, 0, sizeof (*parse));
  parse->all = 0;
  parse->thread_group = -1;
  parse->thread = -1;
  parse->frame = -1;

  cleanup = make_cleanup (mi_parse_cleanup, parse);

  /* Before starting, skip leading white space.  */
  while (isspace (*cmd))
    cmd++;

  /* Find/skip any token and then extract it.  */
  for (chp = cmd; *chp >= '0' && *chp <= '9'; chp++)
    ;
  *token = xmalloc (chp - cmd + 1);
  memcpy (*token, cmd, (chp - cmd));
  (*token)[chp - cmd] = '\0';

  /* This wasn't a real MI command.  Return it as a CLI_COMMAND.  */
  if (*chp != '-')
    {
      while (isspace (*chp))
	chp++;
      parse->command = xstrdup (chp);
      parse->op = CLI_COMMAND;

      discard_cleanups (cleanup);

      return parse;
    }

  /* Extract the command.  */
  {
    char *tmp = chp + 1;	/* discard ``-'' */

    for (; *chp && !isspace (*chp); chp++)
      ;
    parse->command = xmalloc (chp - tmp + 1);
    memcpy (parse->command, tmp, chp - tmp);
    parse->command[chp - tmp] = '\0';
  }

  /* Find the command in the MI table.  */
  parse->cmd = mi_lookup (parse->command);
  if (parse->cmd == NULL)
    error (_("Undefined MI command: %s"), parse->command);

  /* Skip white space following the command.  */
  while (isspace (*chp))
    chp++;

  /* Parse the --thread and --frame options, if present.  At present,
     some important commands, like '-break-*' are implemented by
     forwarding to the CLI layer directly.  We want to parse --thread
     and --frame here, so as not to leave those option in the string
     that will be passed to CLI.  */
  for (;;)
    {
      const char *option;
      size_t as = sizeof ("--all ") - 1;
      size_t tgs = sizeof ("--thread-group ") - 1;
      size_t ts = sizeof ("--thread ") - 1;
      size_t fs = sizeof ("--frame ") - 1;

      if (strncmp (chp, "--all ", as) == 0)
	{
	  parse->all = 1;
	  chp += as;
	}
      /* See if --all is the last token in the input.  */
      if (strcmp (chp, "--all") == 0)
	{
          parse->all = 1;
          chp += strlen (chp);
        }
      if (strncmp (chp, "--thread-group ", tgs) == 0)
	{
	  option = "--thread-group";
	  if (parse->thread_group != -1)
	    error (_("Duplicate '--thread-group' option"));
	  chp += tgs;
	  if (*chp != 'i')
	    error (_("Invalid thread group id"));
	  chp += 1;
	  parse->thread_group = strtol (chp, &chp, 10);
	}
      else if (strncmp (chp, "--thread ", ts) == 0)
	{
	  option = "--thread";
	  if (parse->thread != -1)
	    error (_("Duplicate '--thread' option"));
	  chp += ts;
	  parse->thread = strtol (chp, &chp, 10);
	}
      else if (strncmp (chp, "--frame ", fs) == 0)
	{
	  option = "--frame";
	  if (parse->frame != -1)
	    error (_("Duplicate '--frame' option"));
	  chp += fs;
	  parse->frame = strtol (chp, &chp, 10);
	}
      else
	break;

      if (*chp != '\0' && !isspace (*chp))
	error (_("Invalid value for the '%s' option"), option);
      while (isspace (*chp))
	chp++;
    }

  /* For new argv commands, attempt to return the parsed argument
     list.  */
  if (parse->cmd->argv_func != NULL)
    {
      mi_parse_argv (chp, parse);
      if (parse->argv == NULL)
	error (_("Problem parsing arguments: %s %s"), parse->command, chp);
    }

  /* FIXME: DELETE THIS */
  /* For CLI commands, also return the remainder of the
     command line as a single string. */
  if (parse->cmd->cli.cmd != NULL)
    parse->args = xstrdup (chp);

  discard_cleanups (cleanup);

  /* Fully parsed, flag as an MI command.  */
  parse->op = MI_COMMAND;
  return parse;
}