unix/linux下拷贝文件和目录程序

目的：由于linux下不提供拷贝文件或者目录的函数，很不方便！因此，提供一个封装的函数实现拷贝文件或者目录（带目录内容），实现类似cp -r 的功能，支持相对路径和绝对路径输入。
申明：代码不代表最优的实现，经初步测试没有问题，如有BUG自行修改！

#include <stdio.h>#include <unistd.h>#include <errno.h>#include <dirent.h>#include <sys/stat.h>#include <string.h>int CopyFileExt(char* dest,char* src);int main(int argc,char** argv){/*int ret=0;ret = unlink("/home/caojianping/caotest");printf("unlink return %d\n",ret);printf("ERROR:%s\n",strerror(errno));DelFile("/home/caojianping/caotest");*/if(argc != 3){printf("Usage: copy dest src\n");return -1;}CopyFileExt(argv[1],argv[2]);return 0;}// 目的和源可以是目录也可以是文件// dest == 文件， src == 文件， 删除dest文件，拷贝src文件到dest文件// dest == 目录， src == 文件， 拷贝文件到dest目录下，如有同名文件，覆盖之// dest == 目录， src == 目录， 拷贝src目录内容到dest目录下作为子目录（包括其内容）// dest == 文件， src == 目录， 删除dest文件，拷贝src目录到dest命名的目录// 返回值：0代表 OK，<0 出错int CopyFileExt(char* dest,char* src){struct stat statbuf;struct dirent *dirp;DIR *dp;int ret;int destFile;// 目标是文件标志 0表示目录，1表示文件int srcFile;// 源是文件标志 0表示目录，1表示文件char destFull[256];//存储全路径char srcFull[256];//存储全路径// get the fullpathif(dest[0]!='/')   {getcwd(destFull,sizeof(destFull));strncat(destFull,"/",sizeof(destFull));strncat(destFull,dest,sizeof(destFull));}else{strncpy(destFull,dest,sizeof(destFull));}if(destFull[strlen(destFull)-1] == '/')   // 去掉路径后缀{destFull[strlen(destFull)-1] = '\0';}if(src[0]!='/')   {getcwd(srcFull,sizeof(srcFull));strncat(srcFull,"/",sizeof(srcFull));strncat(srcFull,src,sizeof(srcFull));}else{strncpy(srcFull,src,sizeof(srcFull));}if(srcFull[strlen(srcFull)-1] == '/')   // 去掉路径后缀{srcFull[strlen(srcFull)-1] = '\0';}if(lstat(destFull,&statbuf) < 0){return -1;}if(S_ISDIR(statbuf.st_mode)== 0)   {destFile=1;       // file}else{destFile=0;       // directory}if(lstat(srcFull,&statbuf) < 0){return -1;}if(S_ISDIR(statbuf.st_mode)== 0)   {srcFile=1;       // file}else{srcFile=0;       // directory}// src is fileif(srcFile) {FILE *fpdest;FILE *fpsrc;if(!destFile) {char destpath[256];strncpy(destpath,destFull,255);char *truename = strrchr(srcFull,'/');if(truename){strncat(destpath,truename,255);}fpdest = fopen(destpath,"w");}else{fpdest = fopen(destFull,"w");}if(fpdest==NULL){return -2;}fpsrc = fopen(srcFull,"r");if(fpsrc==NULL){return -2;}//copy filechar buf[1024];int size;int offset=0;do{size = fread (buf,1,sizeof(buf),fpsrc);if(size > 0){fwrite(buf,1,size,fpdest);}}while (!feof(fpsrc));fclose(fpdest);fclose(fpsrc);}else   // src is directory{if(destFile)   // dest is a file, override it{remove(destFull);mkdir(destFull,S_IRWXU|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH);}dp = opendir(srcFull);if(dp == NULL){return -2;}char destpath[256];strncpy(destpath,destFull,255);char *dirname = strrchr(srcFull,'/');if(dirname){strncat(destpath,dirname,255);}mkdir(destpath,S_IRWXU|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH);   // while((dirp = readdir(dp)) != NULL){if(strcmp(dirp->d_name,".")==0 || strcmp(dirp->d_name,"..")==0){continue;}char srcpath[256];strncpy(srcpath,srcFull,255);strncat(srcpath,"/",255);strncat(srcpath,dirp->d_name,255);CopyFileExt(destpath,srcpath);}closedir(dp);}}