www.pudn.com > 12cocorc.zip > SCAN_C.FRM

/********************************************************** 
**   SCAN_C.FRM 
**   Coco/R C Support Frames. 
**   Author: Frankie Arzu  
** 
**   Jun 12, 1996   Version 1.06 
**      Many fixes and suggestions thanks to 
**      Pat Terry  
**   Oct 11, 1997   Version 1.07 (No change) 
**   Mar 13, 1998   Version 1.08 
**      Support for MS VC++ 5.0 
**********************************************************/ 
 
#include -->ScanHeader 
#include  
#include  
#if __MSDOS__ || MSDOS 
#  include  
#  define  SEGMENTED_BUFF   1  /* Segmented Scanner Buffer */ 
#else 
#  if WIN32 
#    include  
#  else 
#    include  
#  endif 
#  define  SEGMENTED_BUFF   0  /* Linear Scanner Buffer */ 
#endif 
 
#ifdef NEXTSTEP   /* NextStep */ 
#  include  
#  include  
#  include  
#  define L_SET     0  /* set the seek pointer */ 
#  define L_INCR    1  /* increment the seek pointer */ 
#  define L_XTND    2  /* extend the file size */ 
#endif 
 
#include  
 
static int STATE0[] = {-->State0}; 
 
int  S_src;                 /* source file */ 
int  S_Line, S_Col;         /* line and column of current symbol */ 
int  S_Len;                 /* length of current symbol */ 
long S_Pos;                 /* file position of current symbol */ 
int  S_NextLine;            /* line of lookahead symbol */ 
int  S_NextCol;             /* column of lookahead symbol */ 
int  S_NextLen;             /* length of lookahead symbol */ 
long S_NextPos;             /* file position of lookahead symbol */ 
static unsigned char S_ch;  /* current input character */ 
int  S_CurrLine;            /* current input line (may be higher than line) */ 
long S_LineStart;           /* start position of current line */ 
 
 
#define Scan_Ch         S_ch 
#define Scan_NextCh     S_NextCh 
#define Scan_ComEols    S_ComEols 
#define Scan_CurrLine   S_CurrLine 
#define Scan_LineStart  S_LineStart 
#define Scan_BuffPos    S_BuffPos 
#define Scan_CurrCol    S_CurrCol 
#define Scan_NextLen    S_NextLen 
 
#if SEGMENTED_BUFF          /* Segmented Buffer for small (MS-DOS) systems */ 
#  define  BLKSIZE  16384 
   static  unsigned char  *Buffer[32]; /* source buffer for low-level access */ 
#  define CURRENT_CH(Pos) (Buffer[(int) (Pos / BLKSIZE)])[(int) (Pos % BLKSIZE)] 
#else 
   static unsigned char *Buffer; 
#  define CURRENT_CH(Pos) Buffer[Pos] 
#endif 
 
static int  S_ComEols;   /* number of EOLs in a comment */ 
static long S_BuffPos;   /* current position in buf */ 
static int  S_CurrCol;   /* current Column Number */ 
static long S_InputLen;  /* source file size */ 
 
unsigned char S_CurrentCh(long pos); 
 
#define IGNORE_CASE  -->IgnoreCase 
#define UPCASE(c)    ((c >= 'a' && c <= 'z') ? c-32 : c) 
 
unsigned char S_CurrentCh(long pos) 
{ return (unsigned char) CURRENT_CH(pos); } 
 
#if IGNORE_CASE 
#define S_NextCh() { S_BuffPos++;\ 
		     S_ch = CURRENT_CH(S_BuffPos);\ 
		     S_ch = UPCASE(S_ch);\ 
		     if (S_ch == TAB_CHAR) S_CurrCol += TAB_SIZE - (S_CurrCol % TAB_SIZE); else \ 
		     if (S_ch == LF_CHAR) {\ 
		       S_CurrLine++; S_CurrCol = 0;\ 
		       S_LineStart = S_BuffPos + 1;}\ 
		     S_CurrCol++;\ 
		   } 
#else 
#define S_NextCh() { S_BuffPos++;\ 
		     S_ch = CURRENT_CH(S_BuffPos);\ 
		     if (S_ch == TAB_CHAR) S_CurrCol += TAB_SIZE - (S_CurrCol % TAB_SIZE); else \ 
		     if (S_ch == LF_CHAR) {\ 
		       S_CurrLine++; S_CurrCol = 0;\ 
		       S_LineStart = S_BuffPos + 1;}\ 
		     S_CurrCol++;\ 
		   } 
#endif 
 
static int EqualStr (char *s) 
{ long q; char c; 
  if (S_NextLen != (int) strlen(s)) return 0; 
  q = S_NextPos; 
  while (*s) { 
    c = CURRENT_CH(q); q++; 
#if IGNORE_CASE 
    c = UPCASE(c); 
#endif 
    if (c != *s++) return 0; 
  } 
  return 1; 
} 
 
static int CheckLiteral(int id) 
{ char c; 
  c = CURRENT_CH(S_NextPos); 
#if IGNORE_CASE 
  c = UPCASE(c); 
#endif 
  switch (c) { 
  -->Literals 
  } 
  return id; 
} 
 
static int Comment() 
{ int Level, StartLine, OldCol; 
  long OldLineStart; 
 
  Level = 1; StartLine = S_CurrLine; 
  OldLineStart = S_LineStart; OldCol = S_CurrCol; 
  -->Comment 
  return 0; 
} 
 
int S_Get() 
{ int state, ctx; 
  start: 
  -->GetIgnore 
  -->GetComment 
 
  S_Pos  = S_NextPos;   S_NextPos  = S_BuffPos; 
  S_Col  = S_NextCol;   S_NextCol  = S_CurrCol - 1; 
  S_Line = S_NextLine;  S_NextLine = S_CurrLine; 
  S_Len  = S_NextLen;   S_NextLen  = 0; ctx = 0; 
 
  if (S_ch == EOF_CHAR) return EOFSym; 
  state = STATE0[S_ch]; 
  while(1) { 
    S_NextCh(); S_NextLen++; 
    switch (state) { 
    -->GetDFA 
    default: return NoSym; /* S_NextCh already done */ 
    } 
  } 
} 
 
void S_GetString (long pos, int len, char *s, int max) 
{ while (len-- && max--) { *s++ = CURRENT_CH(pos); pos++; } 
  *s = '\0'; 
} 
 
void S_GetName (long pos, int len, char *s, int max) 
{ while (len-- && max--) { 
    *s = CURRENT_CH(pos); 
#if IGNORE_CASE 
    *s = UPCASE(*s); 
#endif 
    s++; pos++; 
  } 
  *s = '\0'; 
} 
 
void S_Reset() 
/* assert: S_src has been opened */ 
{ long len; 
  int  i = 0, n; 
 
  S_InputLen = len = lseek(S_src, 0L, SEEK_END); 
  (void) lseek(S_src, 0L, SEEK_SET); 
 
#if SEGMENTED_BUFF 
  while (len > BLKSIZE) { 
    Buffer[i] = (unsigned char *) malloc(BLKSIZE); 
    n = read(S_src, (void *) Buffer[i], (unsigned) BLKSIZE); 
    len -= n; 
    i++; 
  } 
  Buffer[i] = (unsigned char *) malloc((unsigned) len + 1); 
  n = read(S_src, (void *) Buffer[i], (unsigned) len); 
  (Buffer[i])[n] = EOF_CHAR; 
#else  
  Buffer = (unsigned char *) malloc(len+1); 
  n = read(S_src, (void *) Buffer, len); 
  Buffer[n] = EOF_CHAR; 
#endif 
 
  S_CurrLine = 1; S_LineStart = 0; S_BuffPos = -1; S_CurrCol = 0; 
  S_NextPos  = 0; S_NextCol = 0; S_NextLine = 0; S_NextLen = 0; 
  S_ComEols = 0; 
  S_NextCh(); 
}