数据结构与算法分析（C）1.4

问题描述：编写一个程序，使它读入被include语句修饰的一个文件并且输出这个文件。

分析：这道题的思路很简单，首先，读入源文件，然后在源文件中查找#include，然后获取包含的文件名，然后fread到内存中，如此继续下去。
有个问题纠结了很久：当在查找过程中发现strcpy(include,”#include”);时也会出现”#include”字符，应该对它进行过滤。

//include zuhonglei
//
#include <stdio.h>
#include <string.h>

int main(int argc,char *argv[]){
    if(argc<1)
        return -1;
    char *name = argv[0];
    char fullName[20];
    strcpy(fullName,name);
    strcpy(fullName+strlen(name),".c");
    printf("%s\n",fullName);

    FILE *fp = fopen(fullName,"r+");
    if(!fp)
        return -1;
    char context[4097];
    char context2[4097];
    context2[4096] = '\0';
    context[4096] = '\0';

    while(fread(context,sizeof(char),4096,fp)!=0){
        printf("%s\n",context);
    }
    fclose(fp);
    //check the name of include 
    int i,j,index;

    char include[10];
    strcpy(include,"#include");
    index = 0;
    int nameIndex = 0;

    char fileName[40];
    char *prefix = "/usr/include/";
    strcpy(fileName,prefix);
    int fileLen = strlen(fileName);

    for(i = 0;i<4097;i++){  
        if(context[i]=='/'&&context[i+1]=='/')//delete the whole line //
        {
            for(j = i;context[j]!='\n';j++);
            i = j;
            continue;
        }
        if(include[index]!='\0'){
            if(context[i]!=include[index]){
                index = 0;
            }
            else
                index++;
        }
        if(include[index]=='\0'){
            int tmp = fileLen;
            if(context[i+1]!=' '){
            index=0;    
            continue;
            }   
            while(1){
                i++;
                if(context[i]=='>'){
                    index = 0;
                    break;
                }
                if((context[i]>='a'&&context[i]<='z')||context[i]=='.')
                    fileName[tmp++] = context[i];
            }
            fileName[tmp] = '\0';//delete >

            printf("read fileName:%s\n",fileName);
            fp = fopen(fileName,"r+");
            if(!fp)
                return -1;
            while(fread(context2,sizeof(char),4096,fp)!=0)
                printf("%s\n",context2);
            fclose(fp);

        }
    }
    return 0;
}
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