lex.l

%{
#include <stdio.h>

int yacodec_this_byte;
#define yacodec_next_byte  (input())
#define yacodec_next_half1 (yacodec_this_byte=input(),yacodec_this_byte/16)
#define yacodec_next_half2 (yacodec_this_byte%16)
#define yacodec_next_word  (input()*256+input())
#define yacodec_ptr        (yy_c_buf_p)

%}
/* declarations section */
SOF0            \xff\xc0
SOF1            \xff\xc1
SOF2            \xff\xc2
SOF3            \xff\xc3

SOF5            \xff\xc5
SOF6            \xff\xc6
SOF7            \xff\xc7

JPG             \xff\xc8
SOF9            \xff\xc9
SOF10           \xff\xca
SOF11           \xff\xcb

SOF13           \xff\xcd
SOF14           \xff\xce
SOF15           \xff\xcf

TEM             \xff\x01
RES             \xff[\x02-\xbf]

DHT     \xff\xc4 
DAC     \xff\xcc 
RSTm    \xff[\xd0-\xd7]

SOI         \xff\xd8
EOI         \xff\xd9
SOS         \xff\xda
DQT         \xff\xdb
DNL         \xff\xdc
DRI         \xff\xdd
DHP         \xff\xde
EXP         \xff\xdf
APPn        \xff[\xe0-\xef]
JPGn        \xff[\xf0-\xfd]
COM         \xff\xfe
ECS         ([^\xff]|(\xff\x00))+

/* rules section */
%%
{SOI}        {printf("\n[SOI]\t");}
{EOI}        {printf("\n[EOI]\t");}
{SOS}        {int Ns,i;
                    printf("\n[SOS]\t");
                    printf("len:%d ",yacodec_next_word); 
                    Ns = yacodec_next_byte;
                    printf("Ns:%d ",Ns); 
                    for(i = 1 ; i <= Ns; i++){
                        printf("Cs%d:%d ",i,yacodec_next_byte);
                        printf("Td%d:%d ",i,yacodec_next_half1); 
                        printf("Ta%d:%d ",i,yacodec_next_half2); 
                    }
                    printf("Ss:%d ",yacodec_next_byte); 
                    printf("Se:%d ",yacodec_next_byte); 
                    printf("Ah:%d ",yacodec_next_half1); 
                    printf("Al:%d ",yacodec_next_half2); 
             }
{DQT}        {int Lq,i,j,N,Pq;
                    printf("\n[DQT]\t");
                    Lq = yacodec_next_word;
                    printf("len:%d ",Lq); 
                    N = 2;
                    do{
                        Pq = yacodec_next_half1;
                        printf("Pq:%d ",Pq); 
                        printf("Tq:%d ",yacodec_next_half2); 
                        for(j = 0; j < 64; j++){
                            printf("Q%d:%d ",j,(Pq)?yacodec_next_word:yacodec_next_byte);
                        }
                        N += (Pq)?129:65;
                    } while( N < Lq); //!=
             }
{DNL}        {printf("DNL");}
{DRI}        {  printf("\n[DRI]\t");
                printf("len:%d ",yacodec_next_word); 
                printf("Ri:%d ",yacodec_next_word); 
             }
{DHP}        {printf("DHP");}
{EXP}        {printf("EXP");}
{APPn}       {int len;
              char* l = yacodec_ptr;
                printf("\n[APPn]\t");
                len = yacodec_next_word;
                printf("len:%d ap:",len); 
                do{
                    printf("%c",yacodec_next_byte); 
                }while( yacodec_ptr - l < len ); // !=
             }
{JPGn}       {printf("JPGn");}
{COM}        {int len;
              char* l = yacodec_ptr;
                printf("\n[COM]\t");
                len = yacodec_next_word;
                printf("len:%d cm:",len); 
                do{
                    printf("%c",yacodec_next_byte); 
                }while( yacodec_ptr - l < len ); // !=
             }
{ECS}        {printf("\n[ECS]\t");}

{SOF1}            |
{SOF2}            |
{SOF3}            |
{SOF5}            |
{SOF6}            |
{SOF7}            |
{JPG}             |
{SOF9}            |
{SOF10}           |
{SOF11}           |
{SOF13}           |
{SOF14}           |
{SOF15}           |
{SOF0}            {int Nf,i;
                    printf("\n[SOF0]\t");
                    printf("len:%d ",yacodec_next_word); 
                    printf("P:%d ",yacodec_next_byte); 
                    printf("Y:%d ",yacodec_next_word); 
                    printf("X:%d ",yacodec_next_word); 
                    Nf = yacodec_next_byte;
                    printf("Nf:%d ",Nf); 
                    for(i = 1 ; i <= Nf; i++){
                        printf("C%d:%d ",i,yacodec_next_byte);
                        printf("H%d:%d ",i,yacodec_next_half1); 
                        printf("V%d:%d ",i,yacodec_next_half2); 
                        printf("Tq%d:%d ",i,yacodec_next_byte); 
                    }
                  }

{TEM}             {printf("TEM  ");}
{RES}             {printf("RES  ");}

{DHT}           {int i,j,len,L[17];
                 char* l;
                    printf("\n[DHT]\t");
                    l = yacodec_ptr;
                    len = yacodec_next_word;
                    printf("len:%d ",len); 
                    do{
                        printf("Tc:%d ",yacodec_next_half1); 
                        printf("Th:%d ",yacodec_next_half2); 
                        for(i = 1; i <= 16; i++){
                            L[i] = yacodec_next_byte;
                            printf("L%d:%d ",i,L[i]); 
                        }
                        for(i = 1; i <= 16; i++){
                            for(j = 1; j <= L[i]; j++){
                                printf("V(%d,%d):%d ",i,j,yacodec_next_byte); 
                            }
                        }
                    }while( yacodec_ptr - l < len ); // !=
                }
{DAC}           {int len;
                 char* l;
                    printf("\n[DAC]\t");
                    l = yacodec_ptr;
                    len = yacodec_next_word;
                    printf("len:%d ",len); 
                    do{
                        printf("Tc:%d ",yacodec_next_half1); 
                        printf("Tb:%d ",yacodec_next_half2); 
                        printf("Cs:%d ",yacodec_next_byte); 
                    }while( yacodec_ptr - l < len ); // !=
                }
{RSTm}          {printf("RSTm");}

.|\n         {printf(".");}
%%

/* programs section */

#pragma  comment(lib,"y1.lib")
// lex.yy.c:(.text 0xc8f):对‘yywrap’未定义的引用
int yywrap() 
{ 
   return(1); 
} 
int main(void)
{
    //printf("<FONT face=/"Courier New/" size=2>");

	yyin=stdin; 
	yyout=stdout;   

	return yylex();

    //printf("</FONT>");
}