krx12400.c

来自「answer of the c programming language sec」· C语言 代码 · 共 93 行

/******************************************************
   KnR 1-24
   --------
   Write a program to check the syntax of a C program
   for matching {} () "" '' [] 

   Author: Rick Dearman
   email: [e-mail]

******************************************************/
#include <stdio.h>

#define MAXLINE 1000 /* max input line size */
char line[MAXLINE]; /*current input line*/

int getline(void);  /* taken from the KnR book. */


int
main()
{
  int len=0;
  int t=0;
  int brace=0, bracket=0, parenthesis=0;
  int s_quote=1, d_quote=1;


  while ((len = getline()) > 0 )
    {
      t=0;
      while(t < len)
	{
	  if( line[t] == '[')
	    {
	      brace++;
	    }
	  if( line[t] == ']')
	    {
	      brace--;
	    }
	  if( line[t] == '(')
	    {
	      parenthesis++;
	    }
	  if( line[t] == ')')
	    {
	      parenthesis--;
	    }
	  if( line[t] == '\'')
	    {
	      s_quote *= -1;
	    }
	  if( line[t] == '"')
	    {
	      d_quote *= -1;
	    }
	  t++;
	}
    }
  if(d_quote !=1)
    printf ("Mismatching double quote mark\n");
  if(s_quote !=1)
    printf ("Mismatching single quote mark\n");
  if(parenthesis != 0)
    printf ("Mismatching parenthesis\n");
  if(brace != 0)
    printf ("Mismatching brace mark\n");
  if(bracket != 0)
    printf ("Mismatching bracket mark\n");
  if( bracket==0 && brace==0 && parenthesis==0 && s_quote == 1 && d_quote == 1)
        printf ("Syntax appears to be correct.\n");
  return 0;
}


/* getline: specialized version */
int getline(void)
{
  int c, i;
  extern char line[];
  
  for ( i=0;i<MAXLINE-1 && ( c=getchar()) != EOF && c != '\n'; ++i)
    line[i] = c;
  if(c == '\n') 
    {
      line[i] = c;
      ++i;
    }
  line[i] = '\0';
  return i;

}