lempar.c

ethereal公司开发的aodv路由协议代码

/* Driver template for the LEMON parser generator.
** Copyright 1991-1995 by D. Richard Hipp.
**
** This library is free software; you can redistribute it and/or
** modify it under the terms of the GNU Library General Public
** License as published by the Free Software Foundation; either
** version 2 of the License, or (at your option) any later version.
** 
** This library 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
** Library General Public License for more details.
** 
** You should have received a copy of the GNU Library General Public
** License along with this library; if not, write to the
** Free Software Foundation, Inc., 59 Temple Place - Suite 330,
** Boston, MA  02111-1307, USA.
**
** Modified 1997 to make it suitable for use with makeheaders.
*/
/* First off, code is include which follows the "include" declaration
** in the input file. */
#include <stdio.h>
%%
/* Next is all token values, in a form suitable for use by makeheaders.
** This section will be null unless lemon is run with the -m switch.
*/
/* 
** These constants (all generated automatically by the parser generator)
** specify the various kinds of tokens (terminals) that the parser
** understands. 
**
** Each symbol here is a terminal symbol in the grammar.
*/
%%
/* Make sure the INTERFACE macro is defined.
*/
#ifndef INTERFACE
# define INTERFACE 1
#endif
/* The next thing included is series of defines which control
** various aspects of the generated parser.
**    YYCODETYPE         is the data type used for storing terminal
**                       and nonterminal numbers.  "unsigned char" is
**                       used if there are fewer than 250 terminals
**                       and nonterminals.  "int" is used otherwise.
**    YYNOCODE           is a number of type YYCODETYPE which corresponds
**                       to no legal terminal or nonterminal number.  This
**                       number is used to fill in empty slots of the hash 
**                       table.
**    YYACTIONTYPE       is the data type used for storing terminal
**                       and nonterminal numbers.  "unsigned char" is
**                       used if there are fewer than 250 rules and
**                       states combined.  "int" is used otherwise.
**    ParseTOKENTYPE     is the data type used for minor tokens given 
**                       directly to the parser from the tokenizer.
**    YYMINORTYPE        is the data type used for all minor tokens.
**                       This is typically a union of many types, one of
**                       which is ParseTOKENTYPE.  The entry in the union
**                       for base tokens is called "yy0".
**    YYSTACKDEPTH       is the maximum depth of the parser's stack.
**    ParseARGDECL       is a declaration of a 3rd argument to the
**                       parser, or null if there is no extra argument.
**    ParseKRARGDECL     A version of ParseARGDECL for K&R C.
**    ParseANSIARGDECL   A version of ParseARGDECL for ANSI C.
**    YYNSTATE           the combined number of states.
**    YYNRULE            the number of rules in the grammar
**    YYERRORSYMBOL      is the code number of the error symbol.  If not
**                       defined, then do no error processing.
*/
%%
#define YY_NO_ACTION      (YYNSTATE+YYNRULE+2)
#define YY_ACCEPT_ACTION  (YYNSTATE+YYNRULE+1)
#define YY_ERROR_ACTION   (YYNSTATE+YYNRULE)
/* Next is the action table.  Each entry in this table contains
**
**  +  An integer which is the number representing the look-ahead
**     token
**
**  +  An integer indicating what action to take.  Number (N) between
**     0 and YYNSTATE-1 mean shift the look-ahead and go to state N.
**     Numbers between YYNSTATE and YYNSTATE+YYNRULE-1 mean reduce by
**     rule N-YYNSTATE.  Number YYNSTATE+YYNRULE means that a syntax
**     error has occurred.  Number YYNSTATE+YYNRULE+1 means the parser
**     accepts its input.
**
**  +  A pointer to the next entry with the same hash value.
**
** The action table is really a series of hash tables.  Each hash
** table contains a number of entries which is a power of two.  The
** "state" table (which follows) contains information about the starting
** point and size of each hash table.
*/
struct yyActionEntry {
  YYCODETYPE   lookahead;   /* The value of the look-ahead token */
  YYACTIONTYPE action;      /* Action to take for this look-ahead */
  struct yyActionEntry *next; /* Next look-ahead with the same hash, or NULL */
};
static struct yyActionEntry yyActionTable[] = {
%%
};

/* The state table contains information needed to look up the correct
** action in the action table, given the current state of the parser.
** Information needed includes:
**
**  +  A pointer to the start of the action hash table in yyActionTable.
**
**  +  A mask used to hash the look-ahead token.  The mask is an integer
**     which is one less than the size of the hash table.  
**
**  +  The default action.  This is the action to take if no entry for
**     the given look-ahead is found in the action hash table.
*/
struct yyStateEntry {
  struct yyActionEntry *hashtbl; /* Start of the hash table in yyActionTable */
  int mask;                      /* Mask used for hashing the look-ahead */
  YYACTIONTYPE actionDefault;    /* Default action if look-ahead not found */
};
static struct yyStateEntry yyStateTable[] = {
%%
};

/* The following structure represents a single element of the
** parser's stack.  Information stored includes:
**
**   +  The state number for the parser at this level of the stack.
**
**   +  The value of the token stored at this level of the stack.
**      (In other words, the "major" token.)
**
**   +  The semantic value stored at this level of the stack.  This is
**      the information used by the action routines in the grammar.
**      It is sometimes called the "minor" token.
*/
struct yyStackEntry {
  int stateno;       /* The state-number */
  int major;         /* The major token value.  This is the code
                     ** number for the token at this stack level */
  YYMINORTYPE minor; /* The user-supplied minor token value.  This
                     ** is the value of the token  */
};

/* The state of the parser is completely contained in an instance of
** the following structure */
struct yyParser {
  int idx;                            /* Index of top element in stack */
  int errcnt;                         /* Shifts left before out of the error */
  struct yyStackEntry *top;           /* Pointer to the top stack element */
  struct yyStackEntry stack[YYSTACKDEPTH];  /* The parser's stack */
};
typedef struct yyParser yyParser;

#ifndef NDEBUG
#include <stdio.h>
static FILE *yyTraceFILE = 0;
static char *yyTracePrompt = 0;

/* 
** Turn parser tracing on by giving a stream to which to write the trace
** and a prompt to preface each trace message.  Tracing is turned off
** by making either argument NULL 
**
** Inputs:
** <ul>
** <li> A FILE* to which trace output should be written.
**      If NULL, then tracing is turned off.
** <li> A prefix string written at the beginning of every
**      line of trace output.  If NULL, then tracing is
**      turned off.
** </ul>
**
** Outputs:
** None.
*/
void ParseTrace(FILE *TraceFILE, char *zTracePrompt){
  yyTraceFILE = TraceFILE;
  yyTracePrompt = zTracePrompt;
  if( yyTraceFILE==0 ) yyTracePrompt = 0;
  else if( yyTracePrompt==0 ) yyTraceFILE = 0;
}

/* For tracing shifts, the names of all terminals and nonterminals
** are required.  The following table supplies these names */
static char *yyTokenName[] = { 
%%
};
#define YYTRACE(X) if( yyTraceFILE ) fprintf(yyTraceFILE,"%sReduce [%s].\n",yyTracePrompt,X);
#else
#define YYTRACE(X)
#endif

/* 
** This function allocates a new parser.
** The only argument is a pointer to a function which works like
** malloc.
**
** Inputs:
** A pointer to the function used to allocate memory.
**
** Outputs:
** A pointer to a parser.  This pointer is used in subsequent calls
** to Parse and ParseFree.
*/
void *ParseAlloc(void *(*mallocProc)(gulong)){
  yyParser *pParser;
  pParser = (yyParser*)(*mallocProc)( sizeof(yyParser) );
  if( pParser ){
    pParser->idx = -1;
  }
  return pParser;
}

/* The following function deletes the value associated with a
** symbol.  The symbol can be either a terminal or nonterminal.
** "yymajor" is the symbol code, and "yypminor" is a pointer to
** the value.
*/
static void yy_destructor(YYCODETYPE yymajor, YYMINORTYPE *yypminor){
  switch( yymajor ){
    /* Here is inserted the actions which take place when a
    ** terminal or non-terminal is destroyed.  This can happen
    ** when the symbol is popped from the stack during a
    ** reduce or during error processing or when a parser is 
    ** being destroyed before it is finished parsing.
    **
    ** Note: during a reduce, the only symbols destroyed are those
    ** which appear on the RHS of the rule, but which are not used
    ** inside the C code.
    */
%%
    default:  break;   /* If no destructor action specified: do nothing */
  }
}

/*
** Pop the parser's stack once.
**
** If there is a destructor routine associated with the token which
** is popped from the stack, then call it.
**
** Return the major token number for the symbol popped.
*/
static int yy_pop_parser_stack(yyParser *pParser){
  YYCODETYPE yymajor;

  if( pParser->idx<0 ) return 0;
#ifndef NDEBUG
  if( yyTraceFILE && pParser->idx>=0 ){
    fprintf(yyTraceFILE,"%sPopping %s\n",
      yyTracePrompt,
      yyTokenName[pParser->top->major]);
  }
#endif
  yymajor = pParser->top->major;
  yy_destructor( yymajor, &pParser->top->minor);
  pParser->idx--;
  pParser->top--;
  return yymajor;
}

/* 
** Deallocate and destroy a parser.  Destructors are all called for
** all stack elements before shutting the parser down.
**
** Inputs:
** <ul>
** <li>  A pointer to the parser.  This should be a pointer
**       obtained from ParseAlloc.
** <li>  A pointer to a function used to reclaim memory obtained
**       from malloc.
** </ul>
*/
void ParseFree(
  void *p,                 /* The parser to be deleted */
  void (*freeProc)(void *) /* Function used to reclaim memory */
){
  yyParser *pParser = (yyParser*)p;
  if( pParser==0 ) return;
  while( pParser->idx>=0 ) yy_pop_parser_stack(pParser);
  (*freeProc)(pParser);
}

/*
** Find the appropriate action for a parser given the look-ahead token.
**
** If the look-ahead token is YYNOCODE, then check to see if the action is
** independent of the look-ahead.  If it is, return the action, otherwise
** return YY_NO_ACTION.
*/
static int yy_find_parser_action(
  yyParser *pParser,        /* The parser */
  int iLookAhead             /* The look-ahead token */
){
  struct yyStateEntry *pState;   /* Appropriate entry in the state table */
  struct yyActionEntry *pAction; /* Action appropriate for the look-ahead */
 
  /* if( pParser->idx<0 ) return YY_NO_ACTION;  */
  pState = &yyStateTable[pParser->top->stateno];
  if( iLookAhead!=YYNOCODE ){