/* type.h */
#ifndef TTYPE_Z_W
#define TTYPE_Z_W
#define LEN (16)
enum type_tag {IDEN,QUAL,TYPE}; //分别是：标识符、限定符、类型
typedef struct node
{
char *string;
struct node *next;
char type;
} token;
typedef struct
{
token *next;
} poin;
token *creat(void);
int push(poin *,poin *);
int pop(poin *);
enum type_tag classify_string(poin *);
int gettoken(poin *p);
int read_to_first_identifer(poin *n,poin *p);
int deal_with_arrays(poin *p);
int deal_with_func(poin *p);
int deal_with_pointers(poin *n);
int deal_with_declarator(poin *n,poin *p);
#endif
/* type.c */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include "type.h"
token *creat(void)
{
token *s;
if((s=(token *)malloc(sizeof(token)))==NULL)
{
fprintf(stderr,"%s/n","结构体内存分配失败");
return NULL;
}
if((s->string=(char *)malloc(LEN*sizeof(char)))==NULL)
fprintf(stderr,"%s/n","字符数组内存分配失败");
s->type=3;
s->next=NULL;
return s;
}
int push(poin *n,poin *p)
{
p->next->next=n->next;
n->next=p->next;
return 1;
}
int pop(poin *n)
{
token *temp;
temp=n->next;
n->next=temp->next;
free(temp->string);
free(temp);
return 1;
}
enum type_tag classify_string(poin *p)
{
char *s=p->next->string;
if(!strcmp(s,"const"))//if(s==const)
{
strcpy(s,"read-only");
return QUAL;
}
if(!strcmp(s,"volatile")) return QUAL;
if(!strcmp(s,"void")) return TYPE;
if(!strcmp(s,"char")) return TYPE;
if(!strcmp(s,"signed")) return TYPE;
if(!strcmp(s,"unsigned")) return TYPE;
if(!strcmp(s,"short")) return TYPE;
if(!strcmp(s,"int")) return TYPE;
if(!strcmp(s,"long")) return TYPE;
if(!strcmp(s,"float")) return TYPE;
if(!strcmp(s,"double")) return TYPE;
if(!strcmp(s,"struct")) return TYPE;
if(!strcmp(s,"union")) return TYPE;
if(!strcmp(s,"enum")) return TYPE;
return IDEN;
}
int gettoken(poin *p)
{
int n=0,m=LEN;
char *str=p->next->string;
while((*str=getchar())==' ');
if(isalnum(*str)||*str=='_')
{
while(n++,(*++str=getchar())=='_'||isalnum(*str))
{
if(n>=m-2)
{
m+=LEN;
p->next->string=(char *)realloc(p->next->string,m*sizeof(char));
if(p->next->string==NULL)
{
fprintf(stderr,"%s/n","内存扩展失败");
return -1;
}
str=p->next->string+n;
}
}
ungetc(*str,stdin);
*str='/0';
if(n<m-2)
p->next->string=(char *)realloc(p->next->string,(n+1)*sizeof(char));
p->next->type=classify_string(p);
return 1;
}
if(*str=='*')
strcpy(p->next->string,"pointer to");
else
p->next->string[1]='/0';
p->next->type=*str;
p->next->string=(char *)realloc(p->next->string,strlen(p->next->string)*sizeof(char));
return 1;
}
int read_to_first_identifer(poin *n,poin *p)
{
gettoken(p);
while(p->next->type!=IDEN)
{
push(n,p);
p->next=creat();
gettoken(p);
}
printf("%s is ",p->next->string);
gettoken(p);
return 1;
}
int deal_with_arrays(poin *p)
{
while(p->next->type=='[')
{
printf("array ");
gettoken(p);
if(isdigit(p->next->string[0])) //
{
printf("0...%d ",atoi(p->next->string)-1);
gettoken(p); //
}
gettoken(p); //
printf("of ");
}
return 1;
}
int deal_with_func(poin *p) //
{
while(p->next->type!=')')
{
gettoken(p);
}
gettoken(p);
printf("function returning ");//
return 1;
}
int deal_with_pointers(poin *n)//
{
while(n->next->type=='*')
{
printf("%s",n->next->string); //
pop(n);
}
return 1;
}
int deal_with_declarator(poin *n,poin *p)//
{
switch(p->next->type)
{
case '[':
deal_with_arrays(p);
break;
case '(':
deal_with_func(p);
}
deal_with_pointers(n);
while(n->next!=NULL)
{
if(n->next->type=='(')
{
pop(n);
gettoken(p);
deal_with_declarator(n,p);
}
else
{
printf("%s ",n->next->string);
pop(n);
}
}
return 1;
}
/* main.c */
#include <stdio.h>
#include <stdlib.h>
#include "type.h"
int main(void)
{
poin n= {NULL},p;
p.next=creat();
read_to_first_identifer(&n,&p);
deal_with_declarator(&n,&p);
while(n.next!=NULL)
pop(&n);
if(p.next!=NULL)
{
free(p.next->string);
free(p.next);
}
printf("/n");
return 0;
}