注释转换

                    * 状态基思想*

主函数

#define _CRT_SECURE_NO_WARNINGS

#include"CommentConvert.h"

void test()
{
	FILE *pfRead = NULL;
	FILE *pfWrite = NULL;
	pfRead = fopen("input.c", "r");
	if (pfRead == NULL)
	{
		perror("open file for read");
		exit(EXIT_FAILURE);
	}
	pfWrite = fopen("ouput.c", "w");
	if (pfWrite == NULL)
	{
		perror("open file for write");
		fclose(pfRead);
		pfRead = NULL;
		exit(EXIT_FAILURE);
	}
	//注释转换
	CommentConvert(pfRead, pfWrite);
	printf("转换完成\n");
	fclose(pfRead);
	fclose(pfWrite);
	pfRead = NULL;
	pfWrite = NULL;
}

int main()
{
	test();
	system("pause");
	return 0;
}

CommentConvert.h文件

#define _CRT_SECURE_NO_WARNINGS
#ifndef __COMMENTCONVERT_H__
#define __COMMENTCONVERT_H__

//#pragma once 

#include<stdio.h>
#include<stdlib.h>

//状态基编程
typedef enum State
{
	NUL_STATE,
	C_STATE,
	CPP_STATE,
	END_STATE
}State;

void CommentConvert(FILE *pfRead, FILE *pfWrite);
void DoNulState(FILE *pfRead, FILE *pfWrite, State *ps);
void DoCState(FILE *pfRead, FILE *pfWrite, State *ps);
void DoCppState(FILE *pfRead, FILE *pfWrite, State *ps);

#endif //__COMMENTCONVERT_H__

CommentConvert.c文件

#define _CRT_SECURE_NO_WARNINGS

#include"CommentConvert.h"

void CommentConvert(FILE *pfRead, FILE *pfWrite)
{
	State state = NUL_STATE;
	while (state != END_STATE)
	{
		switch (state)
		{
		case NUL_STATE:
			DoNulState(pfRead,pfWrite,&state);
			break;
		case C_STATE:
			DoCState(pfRead, pfWrite, &state);
			break;
		case CPP_STATE:
			DoCppState(pfRead, pfWrite, &state);
			break;
		}
	}
}

void DoNulState(FILE *pfRead, FILE *pfWrite, State *ps)
{
	int first = fgetc(pfRead);
	switch (first)
	{
	case '/':
	{
				int second = fgetc(pfRead);
				switch (second)
				{
				case '*':
				{
							*ps = C_STATE;
							fputc('/', pfWrite);
							fputc('/', pfWrite);
				}
						break;
				case '/':
				{
							*ps = CPP_STATE;
							fputc(first, pfWrite);
							fputc(second, pfWrite);
				}
						break;
				default:
				{
						   fputc(first, pfWrite);
						   fputc(second, pfWrite);
				}
					break;
				}
	}
		break;
	case EOF:
		*ps = END_STATE;
		break;
	default:
		fputc(first, pfWrite);
		break;
	}
}
void DoCState(FILE *pfRead, FILE *pfWrite, State *ps)
{
	int first = fgetc(pfRead);
	switch (first)
	{
	case '*':
	{
				int second = fgetc(pfRead);
				switch (second)
				{
				case '/':
				{
							//多个换行,连续注释
							int third = fgetc(pfRead);
							switch (third)
							{
							case '\n':
							{
										 fputc(third, pfWrite);
										 *ps = NUL_STATE;
							}
								break;
							case '/':
							{
										fputc('\n', pfWrite);
										ungetc(third, pfRead);
										*ps = NUL_STATE;
							}
								break;
							default:
							{
									   fputc('\n', pfWrite);
									   fputc(third, pfWrite);
									   *ps = NUL_STATE;
							}
								break;
							}
				}
					break;
				case '*':
				{
							// * 的送回
							fputc(first, pfWrite);
							ungetc(second, pfRead);
				}
					break;
				default:
				{
						   fputc(first, pfWrite);
						   fputc(second, pfWrite);
				}
					break;
				}
	}
		break;
	case '\n':
	{
				 fputc(first, pfWrite);
				 fputc('/', pfWrite);
				 fputc('/', pfWrite);
	}
		break;
	default:
		fputc(first, pfWrite);
		break;
	}
}
void DoCppState(FILE *pfRead, FILE *pfWrite, State *ps)
{
	int first = fgetc(pfRead);
	switch (first)
	{
	case '\n':
	{
				 *ps = NUL_STATE;
				 fputc('\n', pfWrite);
	}
		break;
	case EOF:
	{
				*ps = END_STATE;
	}
		break;
	default:
		fputc(first, pfWrite);
		break;
	}
}