文件遍历搜索（File System Traversal）

问题描述：

本文使用C语言实现了简单的文件遍历搜索功能并将搜索结果排序输出（测试平台为Ubuntu)，本程序接受以下格式输入：

输入

search.o [-n NAME] [-L] path

• path: 搜索开始的根地址，可以为相对或者绝对路径
• -n NAME: 被搜索文件的文件名模板，程序只输出文件名符合该模板的文件名，这个模板和shell风格的通配符一致：
  • *: 匹配任何文件，没有-n name参数时，默认仅有一个*号，即输出该路径下所有文件 
  • ?: 匹配任何单字符
  • [seq]: 匹配包含seq字符串的任何文件名
  • [!seq]: 匹配不包含seq字符串的任何文件名
• -L: 符号链接，如果有该参数，则符号链接也考虑在内，即程序会进入符号链接的文件下继续递归搜索

输出

• 一行输出一个搜索结果
• 在每一行，打印的结果以以下格式要求输出：
  • Mode: 一个九个字符的字符串，代表该文件的访问权限，实现的功能类似于命令： ls -l filename | cut -b 2-10 .
  • Size: the size of the file in a decimal number in bytes.一个十进制的数，代表该文件的大小（以字节计算）
  • Extended file name:完整的文件名，包含文件路径和文件名
• 输出结果按照文件名的ASCII码表排序输出

源码：search.c

//Written by Openking 2014-12-31/*usage: search.o [-h] [-n NAME] [-L] pathpositional arguments:  path                  Pathoptional arguments:  -h, --help            show this help message and exit  -n NAME, --name NAME  File name pattern  -L, --followlinks     Follow symbolic links*/#include <locale.h>#include <fnmatch.h>#include <stdio.h>#include <errno.h>#include <string.h>#include <sys/types.h>#include <dirent.h>#include <stdbool.h>#include <stdlib.h>#include <sys/stat.h>#define MAX_PATH_LENGTH512//global variableschar*name ="*";bool Have_n = 0, Have_L = 0;char dir_Path[10000][MAX_PATH_LENGTH];char output[10000][MAX_PATH_LENGTH+20];int num = 0;void sort(char path1[][MAX_PATH_LENGTH],char path2[][MAX_PATH_LENGTH+20],int n){    char temp1[MAX_PATH_LENGTH],temp2[MAX_PATH_LENGTH+20];    int i,j,k;    for(i = 0; i < n; i++)    {        k = i;        for(j = i + 1; j < n; j++)            if(strcmp(path1[k],path1[j]) > 0)            k = j;        if(k != i)        {            strcpy(temp1,path1[i]);            strcpy(temp2,path2[i]);            strcpy(path1[i],path1[k]);            strcpy(path2[i],path2[k]);            strcpy(path1[k],temp1);            strcpy(path2[k],temp2);        }    }}void doSearch(char *path){DIR *ptr_dir;struct dirent *dir_entry;int i = 0;char *child_path;char *file_path;child_path = (char*)malloc(sizeof(char)*MAX_PATH_LENGTH);memset(child_path, 0, sizeof(char)*MAX_PATH_LENGTH);file_path = (char*)malloc(sizeof(char)*MAX_PATH_LENGTH);memset(file_path, 0, sizeof(char)*MAX_PATH_LENGTH);ptr_dir = opendir(path);while((dir_entry = readdir(ptr_dir)) != NULL){if(dir_entry->d_type == DT_DIR)    //directory{if(strcmp(dir_entry->d_name,".") == 0 ||   strcmp(dir_entry->d_name,"..") == 0)continue;sprintf(child_path, "%s/%s", path, dir_entry->d_name);//printf("[DIR]%s\n", child_path);doSearch(child_path);continue;}else if(dir_entry->d_type == DT_LNK)    //symbol link{sprintf(child_path, "%s/%s", path, dir_entry->d_name);//printf("[Link]%s\n", child_path);//printf("dir:%d lnk:%d reg:%d\n",DT_DIR,DT_LNK,DT_REG);struct stat sb;stat(child_path, &sb);if((sb.st_mode & S_IFMT) == S_IFDIR)if(Have_L)doSearch(child_path);else continue;else goto L1;}else if(dir_entry->d_type == DT_REG){L1:if(fnmatch(name, dir_entry->d_name, FNM_PATHNAME|FNM_PERIOD) == 0){sprintf(file_path, "%s/%s", path, dir_entry->d_name);//printf("[FILE]%s\n", file_path);sprintf(dir_Path[num], "%s",file_path);struct stat file;char power[] = "---------";int size_file = 0,mode = 0;lstat(file_path,&file);size_file = file.st_size;mode = file.st_mode;if(mode & S_IRUSR) power[0] = 'r';if(mode & S_IWUSR) power[1] = 'w';if(mode & S_IXUSR) power[2] = 'x';if(mode & S_IRGRP) power[3] = 'r';if(mode & S_IWGRP) power[4] = 'w';if(mode & S_IXGRP) power[5] = 'x';if(mode & S_IROTH) power[6] = 'r';if(mode & S_IWOTH) power[7] = 'w';if(mode & S_IXOTH) power[8] = 'x';sprintf(output[num++], "%s %d %s",power,size_file,file_path);}}}free(child_path);child_path = NULL;free(file_path);file_path = NULL;}int main(int argc, char*argv[], char *env[]){int i,j;static char str1[] = "-n", str2[] = "-L";char*dir;    for(i = 1; i < argc; i++)    // Deal the strings{//printf("argv[%d]:%s\n", i, argv[i]);  //Output the command parameterif(strcmp(argv[i], str1) == 0){Have_n = 1;name = argv[i+1];    //if have -n ,then record the namei++;      //skip the next name//printf("name: %s\n",name);continue;}else if(strcmp(argv[i], str2) == 0)Have_L = 1;else{dir = argv[i];     //record the directoryint num_ch = strlen(dir);if(dir[num_ch - 1] =='/')dir[num_ch-1] = 0;//printf("directory: %s\n",dir);}}//printf("-L: %d; -n: %d\n",Have_L,Have_n);doSearch(dir);sort(dir_Path,output,num);for(i = 0; i < num; i++){printf("%s\n",output[i]);}return 0;}

测试输入：

search.o -n "*.py" -L ~/Desktop/workspace/python/

结果：

('rw-rw-r--', 1080, '/home/openking/Desktop/workspace/python/search.py')('rw-rw-r--', 2442, '/home/openking/Desktop/workspace/python/shell.py')('rw-rw-r--', 2262, '/home/openking/Desktop/workspace/python/test.py')