trieFA.h

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/* File - trieFA.h
 *
 *    This file contains code to be included in the scanner file using a
 * generated trie-based FA.
 */
 
typedef struct {                                /* An entry in the FA state table                       */
        short                   def;            /*      If this state is an accepting state then*/
                                                                /*      this is the definition, otherwise -1.   */
        short                   trans_base;     /* The base index into the transition table.*/
        long                    mask;           /* The transition mask.                                         */
}TrieState ;
 
typedef struct {                                /* An entry in the FA transition table.         */
        short                   c;                              /* The transition character (lowercase).*/
        short                   next_state;             /* The next state.                                              */
}TrieTrans ;
 
#ifdef UNDERLINE
static long CharMask[28] = {
        0x0000001,      0x0000000,      0x0000004,      0x0000008,      
        0x0000010,      0x0000020,      0x0000040,      0x0000080,
        0x0000100,      0x0000200,      0x0000400,      0x0000800,
        0x0001000,      0x0002000,      0x0004000,      0x0008000,
        0x0010000,      0x0020000,      0x0040000,      0x0080000,
        0x0100000,      0x0200000,      0x0400000,      0x0800000,
        0x1000000,      0x2000000,  0x4000000,  0x8000000,
};
 
#define IN_MASK_RANGE(C)        (islower(C) || ((C) == '_'))
#define MASK_INDEX(C)   ((C) - '_')
 
#else
static long CharMask[26] = {
        0x0000001,      0x0000002,      0x0000004,      0x0000008,      
        0x0000010,      0x0000020,      0x0000040,      0x0000080,
        0x0000100,      0x0000200,      0x0000400,      0x0000800,
        0x0001000,      0x0002000,      0x0004000,      0x0008000,
        0x0010000,      0x0020000,      0x0040000,      0x0080000,
        0x0100000,      0x0200000,      0x0400000,      0x0800000,
        0x1000000,      0x2000000                                               
};
 
#define IN_MASK_RANGE(C)        islower(C)
#define MASK_INDEX(C)           ((C) - 'a')
 
#endif
 
static short            TFA_State;
 
/* TFA_Init:
 *
 *    Initialize the trie FA.
 */
#define TFA_Init() TFA_State = 0
 
/* TFA_Advance:
 *
 *    Advance to the next state (or -1) on the lowercase letter c. 
 */
#define TFA_Advance(C)  {                                                                                                                       \
        char            c = C;                                                                                                                          \
        if (TFA_State >= 0) {                                                                                                                   \
                if (isupper((int)c))                                                                                                                            \
                        c = (char)tolower((int)c);                                                                                                                      \
                else if (! IN_MASK_RANGE(c)) {                                                                                          \
                        TFA_State = -1;                                                                                                                 \
                        goto TFA_done;                                                                                                                  \
                }                                                                                                                                                       \
                if (TrieStateTbl[TFA_State].mask & CharMask[MASK_INDEX(c)]) {                           \
                        short           i = TrieStateTbl[TFA_State].trans_base;                                         \
                        while (TrieTransTbl[i].c != c)                                                                                  \
                                i++;                                                                                                                            \
                        TFA_State = TrieTransTbl[i].next_state;                                                                 \
                }                                                                                                                                                       \
                else                                                                                                                                            \
                        TFA_State = -1;                                                                                                                 \
        }                                                                                                                                                               \
  TFA_done:;                                                                                                                                            \
} /* end of TFA_Advance. */
 
/* TFA_Definition:
 *
 *    Return the definition (if any) associated with the current state.
 */
#define TFA_Definition() \
        ((TFA_State < 0) ? -1 : TrieStateTbl[TFA_State].def)