linux c遍历文件夹

#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <stdlib.h>
#include <pthread.h>
#include <dirent.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>


void sys_err(const char *err,int code)
{
	perror(err);
	if (errno == EACCES)
		return;
	exit(code);
}


typedef struct thread_arg{
	char filename[256];
	char ext[32];
}*pthread_arg,thread_arg;


typedef struct extension{
	char filename[4096];
	struct extension *pnext;
}*pext,ext;


pext phead = NULL;
void create_list(pext *phead,char *filename)
{
	if (*phead == NULL)
	{
		pext node = (pext)malloc(sizeof(ext));
		if (!node)
			return;
		strcpy(node->filename,filename);
		*phead = node;
		node->pnext = NULL;
	}
	else
	{
		pext ptr = *phead;
		while(ptr->pnext != NULL)
			ptr = ptr->pnext;


		pext node = (pext)malloc(sizeof(ext));
		if (!node)
			return;
		strcpy(node->filename,filename);
		ptr->pnext = node;
		node->pnext = NULL;
	}
	return;
}


char *get_ext(const char *filename)
{
	char *ptr = strchr(filename,'.');
	if (!ptr)
		return NULL;
	return ptr;
}


void *traverse(void *arg)
{
	pthread_arg parg = (pthread_arg)arg;


	DIR *dp;
	struct dirent *dirp;
	if ((dp = opendir(parg->filename)) == NULL)
	{
		sys_err("opendir",1);
		return (void *)NULL;
	}
	chdir(parg->filename);
	while((dirp = readdir(dp)) != NULL)
	{
		if (!strcmp(dirp->d_name,".") || !strcmp(dirp->d_name,".."))
			continue;


		char *ptr = get_ext(dirp->d_name);
		if (ptr != NULL)
		{
			if (!strcmp(ptr,parg->ext))
			{
				char temp[4096];
				getcwd(temp,4096);
				//get the full path
				strcat(temp,dirp->d_name);
				create_list(&phead,temp);
			}
		}


		if (dirp->d_type == DT_DIR)
		{
			strcpy(parg->filename,dirp->d_name);
			traverse((void *)parg);
		}
	}
	chdir("..");
	closedir(dp);
	return (void *)NULL;
}


char **split(ssize_t count,ssize_t size,char data[],const char *spl)
{
	char **buff = (char **)calloc(count,sizeof(char*));
	if (!buff)
		return NULL;


	for (ssize_t i = 0;i<count;i++)
		buff[i] = (char *)calloc(size,sizeof(char));


	char *token = strtok(data,spl);
	int i = 0;
	while(token)
	{
		strcpy(buff[i],token);
		token = strtok(NULL,spl);	
		i++;
	}
	return buff;
}


int get_spl_count(char *str)
{
	int i = 0;
	while(*str != '\0')
	{
		if (*str == '|')
			i++;
		str++;
	}
	if (!i)
		return -1;
	return i+1;
}


char *get_file_content(const char *filepath)
{
	int fd = open(filepath,O_RDONLY);
	if (fd == -1)
		sys_err("open",1);


	long size = lseek(fd,SEEK_SET,SEEK_END);
	lseek(fd,SEEK_SET,SEEK_SET);
	if (size == -1)
		sys_err("lseek",1);


	char *buff = (char *)calloc(size,sizeof(char));
	if (!buff)
		return NULL;


	int result = read(fd,buff,size);
	if (result == -1)
		return NULL;


	close(fd);
	return buff;
}


void show_list(pext head)
{
	while(head != NULL)
	{
		puts(head->filename);
		// do evil
		head = head->pnext;
	}
}


void destory_list(pext *head)
{
	if (*head == NULL)
		return;
	pext p1,p2;
	p1 = p2 = NULL;
	p1 = *head;
	while(p1->pnext != NULL)
	{
		p2 = p1->pnext;
		p1->pnext = p2->pnext;
		free(p2);
		if (p2 != NULL)
			p2 = NULL;
	}
	free(*head);
	if (*head != NULL)
		*head = NULL;
	return;
}


void execute(char *str)
{
	int spl_count = get_spl_count(str);
	if (spl_count == -1)
	{
		printf("file content:.doc|.exe|.jpg|.png\n");
		exit(EXIT_FAILURE);
	}
	pthread_t *thread = (pthread_t *)calloc(spl_count,sizeof(pthread_t));
	char **result = split(spl_count,32,str,"|");
	for (ssize_t i = 0;i< spl_count;i++)
	{
		thread_arg arg;
		strcpy(arg.filename,"/");
		strcpy(arg.ext,result[i]);
		pthread_create(thread+i,NULL,(void *)traverse,(void *)&arg);
		pthread_join(thread[i],NULL);
	}
	free(result);
}


int main(int argc,char **argv)
{
	if (argc == 2)
		execute(argv[1]);


	if (argc == 3 && *(*(argv+1)+1) == 'f')
	{
		char *buff = get_file_content(argv[2]);
		if (buff != NULL && strcmp(buff,""))
		{
			execute(buff);
			free(buff);
		}
	}
	show_list(phead);
	destory_list(&phead);
	return 0;
}