/*
   rcfile.h

   This file is part of GNU Anubis.
   Copyright (C) 2003-2014 The Anubis Team.

   GNU Anubis 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.

   GNU Anubis 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 GNU Anubis.  If not, see <http://www.gnu.org/licenses/>.
*/

/* Types describing the basic syntax of an anubis rc file */
typedef struct rc_section RC_SECTION;
typedef struct rc_stmt RC_STMT;
typedef struct rc_rule RC_RULE;
typedef struct rc_cond RC_COND;
typedef struct rc_asgn RC_ASGN;
typedef struct rc_node RC_NODE;
typedef struct rc_bool RC_BOOL;
typedef struct rc_expr RC_EXPR;
typedef struct rc_inst RC_INST;
typedef struct rc_loc RC_LOC;

struct rc_loc
{
  char *file;
  size_t line;
  size_t column;
};

/* Input location for the parser */
struct rc_yyltype
{
  struct rc_loc beg;
  struct rc_loc end;
};

#define YYLTYPE struct rc_yyltype

#define RC_LOCUS_FILE_EQ(a,b)						\
  (((a)->file == (b)->file) ||						\
   ((a)->file && (b)->file && strcmp ((a)->file, (b)->file) == 0))

#define RC_LOCUS_EQ(a,b)				\
  (RC_LOCUS_FILE_EQ(a,b) && (a)->line == (b)->line)

struct rc_section
{				/* RC Section */
  RC_LOC loc;			/* Location in the config file */
  RC_SECTION *next;		/* Link to the next section */
  char *name;			/* Section name */
  RC_STMT *stmt;		/* List of parsed statements */
};

enum rc_stmt_type
{				/* Statement type: */
  rc_stmt_asgn,			/* Assignment */
  rc_stmt_rule,			/* Rule definition */
  rc_stmt_cond,			/* Conditional expression */
  rc_stmt_inst			/* Instruction */
};

struct rc_asgn
{				/* Assignment */
  char *lhs;			/* Left-hand side: A keyword */
  ANUBIS_LIST rhs;		/* Right-hand side: A list of character strings */
  int flags;			/* Flags control various aspects of assignment
				   functionality */
};

enum bool_op
{				/* Boolean operator */
  bool_not,
  bool_and,
  bool_or
};

struct rc_bool
{				/* Boolean expression */
  enum bool_op op;		/* Opcode */
  RC_NODE *left;		/* Left operand */
  RC_NODE *right;		/* Right operand (NULL for bool_not) */
};

enum rc_node_type
{				/* Executable node type */
  rc_node_bool,			/* Boolean instruction */
  rc_node_expr			/* Regular expression */
};

struct rc_expr
{
  int part;			/* HEADER, COMMAND or BODY */
  char *sep;                    /* If not-null, concatenate all values of
				   a same key, using this string as a separator
				   before matching */
  char *key;
  RC_REGEX *re;
};

struct rc_node
{				/* Executable node */
  RC_LOC loc;			/* Location in the config file */
  enum rc_node_type type;	/* Node type */
  union
  {
    RC_EXPR expr;
    RC_BOOL bool;
  }
  v;
};

struct rc_cond
{				/* Conditional expression */
  RC_NODE *node;		/* Condition node */
  RC_STMT *iftrue;		/* Branch to follow when the condition is true */
  RC_STMT *iffalse;		/* Branch to follow when the condition is false */
};

struct rc_rule
{				/* Rule definition */
  RC_NODE *node;		/* Compiled regular expression */
  RC_STMT *stmt;		/* Body of the rule */
};

enum rc_inst_opcode
{				/* Operation code */
  inst_add,
  inst_remove,
  inst_modify,
  inst_stop,
  inst_call
};

struct rc_inst
{				/* Instruction definition */
  enum rc_inst_opcode opcode;
  int part;			/* Message part to operate upon */
  RC_REGEX *key;		/* Key */
  char *key2;			/* New key value (for modify) */
  char *arg;			/* Argument */
};

struct rc_stmt
{				/* General statement representation */
  RC_LOC loc;			/* Location in the config file */
  RC_STMT *next;		/* Link to the next statement */
  enum rc_stmt_type type;	/* Statement type */
  union
  {				/* Actual data */
    RC_ASGN asgn;		/* type == rc_stmt_asgn */
    RC_RULE rule;		/* type == rc_stmt_rule */
    RC_COND cond;		/* type == rc_stmt_cond */
    RC_INST inst;		/* type == rc_stmt_inst */
  }
  v;
};

/* Semantic handler tables */

typedef void (*rc_kw_parser_t) (EVAL_ENV env, int key, ANUBIS_LIST arg,
				void *inv_data);

/* Keyword flags */
#define KWF_HIDDEN 0x0001	/* Replace RHS with stars in debugging output */

struct rc_kwdef
{
  char *name;			/* Keyword name */
  int tok;			/* Assigned token number */
  int flags;			/* Flags controlling debugging output, etc. */
};

struct rc_secdef_child
{
  struct rc_secdef_child *next;
  int method;
  struct rc_kwdef *kwdef;
  rc_kw_parser_t parser;
  void *data;
};

/* Section priorities affect linking the user-defined sections to
   the parse tree left from parsing the system configuration file. */
enum section_prio
{
  prio_user_only,		/* Only user-defined section is taken into account */
  prio_system_only,		/* Only system-defined section */
  prio_system,			/* System-defined section first, user-defined next */
  prio_user			/* User-defined section first, system-defined next */
};

struct rc_secdef
{
  char *name;			/* Section name */
  enum section_prio prio;	/* Execution priority */
  int allow_prog;		/* Are rules allowed in this section? */
  struct rc_secdef_child *child;
};

typedef void (*RC_ERROR_PRINTER) (void *data,
				  struct rc_loc *loc,
				  const char *pfx,
				  const char *fmt, va_list ap);

/* Global data */
struct rc_loc rc_locus;

/* Function declarations */
void verbatim (void);
void lex_clear_state (void);

int error_sync_begin ();

RC_SECTION *rc_section_lookup (RC_SECTION *, char *);
void rc_section_link (RC_SECTION **, RC_SECTION *);
void rc_secdef_add_child (struct rc_secdef *, struct rc_secdef_child *);
RC_SECTION *rc_parse (char *);
RC_SECTION *rc_parse_ep (char *name, RC_ERROR_PRINTER errprn, void *data);
void rc_section_list_destroy (RC_SECTION **);
int rc_run_cond (char *, int, char *);
void rc_run_section (int, RC_SECTION *, struct rc_secdef *, const char *,
		     void *, MESSAGE);
void rc_set_debug_level (char *);
int rc_open (char *);
struct rc_secdef *anubis_add_section (char *);
struct rc_secdef *anubis_find_section (char *);

void parse_error (struct rc_loc *loc, const char *fmt, ...)
  ANUBIS_PRINTFLIKE(2,3);
void tracefile (RC_LOC *, const char *fmt, ...)
  ANUBIS_PRINTFLIKE(2,3);

extern int yy_flex_debug;
/* EOF */