C++用来检测数据类型的声明工具代码

#include <stdio.h>  #include <stdlib.h>  #include <ctype.h>  #include <string.h>  #define MAXTOKENS 100  #define MAXTOKENLEN 64      enum type_tag{IDENTIFIER, QUALIFIER, TYPE}; /*标识符，限定符，类型*/      struct token{      char type;      char string[MAXTOKENLEN];  };      int top = -1;  struct token stack[MAXTOKENS];  struct token this;      #define pop stack[top--]  #define push(s) stack[++top] = s      #define STRCMP(a,R,b) (strcmp(a,b) R 0)      /*推断标识符类型*/  enum type_tag classify_string(void)  {      char *s = this.string;      if (STRCMP(s,==,"const"))      {          strcpy(s,"read-only");          return QUALIFIER;      }      if (STRCMP(s,==,"volatile")) return QUALIFIER;      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,==,"double")) return TYPE;      if (STRCMP(s,==,"float")) return TYPE;      if (STRCMP(s,==,"struct")) return TYPE;      if (STRCMP(s,==,"union")) return TYPE;      if (STRCMP(s,==,"enum")) return TYPE;      return IDENTIFIER;  }      /*读取下一个标记到"this"  *可能读入的字符包括：字母、数字、*[]()  */  void gettoken(void)  {      char *p = this.string;              /*略过空白字符*/      while((*p = (char)getchar()) == ' ') ;              /*是字母或数字*/      if (isalnum(*p))      {          while(isalnum(*++p = (char)getchar())) ; /*读到下一个不是字母或数字为止*/          ungetc(*p,stdin);  /*将一个字符回退到输入流*/          *p = '';          this.type = (char)classify_string();          return;      }              if (*p == '*')      {          strcpy(this.string,"pointer to");          this.type = '*';          return;      }              this.string[1] = '';      this.type = *p;      return;  }      /*理解所有分析过程的代码段*/  int read_to_first_identifier(void)  {      gettoken(); /*取第一个标记*/      while(this.type != (char)IDENTIFIER) /* 取到标识符终止，标识符未压入栈 */      {          push(this);          gettoken();      }              printf("%s is ",this.string);      gettoken();/*再取标识符右边一个符号*/      return 0;  }      int deal_with_arrays(void)  {      while(this.type == '[')      {          printf("array ");          gettoken();/*数字域或']'*/          if (isdigit(this.string[0]))          {              printf("0..%d ",atoi(this.string)-1);              gettoken(); /*取']'*/          }                      gettoken(); /* 读取']'后的下一个标记，可能还是一个'[' */          printf("of ");      }              return 0;  }      int deal_with_function_args(void)  {      while(this.type != ')') /* 把函数参数取出来丢弃 */      {          gettoken();      }              gettoken(); /* 读取')'后的下一个标记 */      printf("function returning ");      return 0;  }      int deal_with_pointers(void)  {      while(stack[top].type == '*')      {          printf("%s ",pop.string);      }      return 0;  }      int deal_with_declarator(void)  {      /*处理标识符后可能存在的数组或函数*/      switch(this.type)      {          case '[' : deal_with_arrays();break;          case '(' : deal_with_function_args();break;          default : break;      }              deal_with_pointers(); /* 栈顶元素是'*' */              /*处理在读到标识符之前压入堆栈的符号*/      while(top >= 0)      {          if (stack[top].type == '(')          {              pop;              gettoken(); /* 读取')'之后的符号，可能是'('或'[' */              deal_with_declarator();  /* 递归调用 */          }          else          {              printf("%s ",pop.string);          }      }              return 0;  }      int main(void)  {      /*将标记压入堆栈中，直到遇见标识符*/      read_to_first_identifier();      deal_with_declarator();      printf("n");              return 0;  }
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C++用来检测数据类型的声明工具代码
