/* MI Command Set - MI parser.

   Copyright (C) 2000-2022 Free Software Foundation, Inc.
   Copyright (C) 2022 Advanced Micro Devices, Inc. All rights reserved.

   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 "cli/cli-utils.h"
#include "language.h"

static const char mi_no_values[] = "--no-values";
static const char mi_simple_values[] = "--simple-values";
static const char mi_all_values[] = "--all-values";

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

static int
mi_parse_escape (const 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 (const char *args, struct mi_parse *parse)
{
  const char *chp = args;
  int argc = 0;
  char **argv = XNEWVEC (char *, argc + 1);

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

      /* Skip leading white space.  */
      chp = skip_spaces (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;
	    const 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 = XNEWVEC (char, len + 1);
	    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;
	    const char *start = chp;

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

mi_parse::mi_parse ()
  : op (MI_COMMAND),
    command (NULL),
    token (NULL),
    cmd (NULL),
    cmd_start (NULL),
    args (NULL),
    argv (NULL),
    argc (0),
    all (0),
    thread_group (-1),
    thread (-1),
    lane (-1),
    frame (-1),
    language (language_unknown)
{
}

mi_parse::~mi_parse ()
{
  xfree (command);
  xfree (token);
  xfree (args);
  freeargv (argv);
}

std::unique_ptr<struct mi_parse>
mi_parse (const char *cmd, char **token)
{
  const char *chp;

  std::unique_ptr<struct mi_parse> parse (new struct mi_parse);

  /* Before starting, skip leading white space.  */
  cmd = skip_spaces (cmd);

  /* Find/skip any token and then extract it.  */
  for (chp = cmd; *chp >= '0' && *chp <= '9'; chp++)
    ;
  *token = (char *) 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 != '-')
    {
      chp = skip_spaces (chp);
      parse->command = xstrdup (chp);
      parse->op = CLI_COMMAND;

      return parse;
    }

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

    for (; *chp && !isspace (*chp); chp++)
      ;
    parse->command = (char *) 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)
    throw_error (UNDEFINED_COMMAND_ERROR,
		 _("Undefined MI command: %s"), parse->command);

  /* Skip white space following the command.  */
  chp = skip_spaces (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.

     Same for the --language option.  */

  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 lane_s = sizeof ("--lane ") - 1;
      size_t fs = sizeof ("--frame ") - 1;
      size_t lang_s = sizeof ("--language ") - 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)
	{
	  char *endp;

	  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, &endp, 10);
	  chp = endp;
	}
      else if (strncmp (chp, "--thread ", ts) == 0)
	{
	  char *endp;

	  option = "--thread";
	  if (parse->thread != -1)
	    error (_("Duplicate '--thread' option"));
	  chp += ts;
	  parse->thread = strtol (chp, &endp, 10);
	  chp = endp;
	}
      else if (strncmp (chp, "--lane ", lane_s) == 0)
	{
	  char *endp;

	  option = "--lane";
	  if (parse->lane != -1)
	    error (_("Duplicate '--lane' option"));
	  chp += lane_s;
	  parse->lane = strtol (chp, &endp, 10);
	  chp = endp;
	}
      else if (strncmp (chp, "--frame ", fs) == 0)
	{
	  char *endp;

	  option = "--frame";
	  if (parse->frame != -1)
	    error (_("Duplicate '--frame' option"));
	  chp += fs;
	  parse->frame = strtol (chp, &endp, 10);
	  chp = endp;
	}
      else if (strncmp (chp, "--language ", lang_s) == 0)
	{
	  option = "--language";
	  chp += lang_s;
	  std::string lang_name = extract_arg (&chp);

	  parse->language = language_enum (lang_name.c_str ());
	  if (parse->language == language_unknown
	      || parse->language == language_auto)
	    error (_("Invalid --language argument: %s"), lang_name.c_str ());
	}
      else
	break;

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

  /* For new argv commands, attempt to return the parsed argument
     list.  */
  if (parse->cmd->argv_func != NULL)
    {
      mi_parse_argv (chp, parse.get ());
      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);

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

enum print_values
mi_parse_print_values (const char *name)
{
   if (strcmp (name, "0") == 0
       || strcmp (name, mi_no_values) == 0)
     return PRINT_NO_VALUES;
   else if (strcmp (name, "1") == 0
	    || strcmp (name, mi_all_values) == 0)
     return PRINT_ALL_VALUES;
   else if (strcmp (name, "2") == 0
	    || strcmp (name, mi_simple_values) == 0)
     return PRINT_SIMPLE_VALUES;
   else
     error (_("Unknown value for PRINT_VALUES: must be: \
0 or \"%s\", 1 or \"%s\", 2 or \"%s\""),
	    mi_no_values, mi_all_values, mi_simple_values);
}