Recursive rm implementation in C - Need help

[ajith_kamath]

Hi,

I am trying to implement rm - r functionality in C without using "System" method.

Below is Code i have written. The program goes into infinite loop and I am not able to trace the bug.

Please help.

#include<stdio.h>
#include <dirent.h>
#include <sys/stat.h>

#include<malloc.h>
#include<string.h>
#include <sys/types.h>



int removedir(char *path)

{


int counter =1;


DIR *pdir = NULL;
struct dirent *pent = NULL;
struct stat eStat;
pdir = opendir(path);


if ( pdir == NULL)
{
return -1;
}


while ( (pent=readdir(pdir)) != NULL )
{

// printf("\n %s\n" ,pent->d_name);
if(((pent->d_name)==".")||((pent->d_name)==".."))
{
continue;
}
else
{

stat(pent->d_name, &eStat);
if(S_ISDIR(eStat.st_mode))
{
path=strcat(path,"/");
path=strcat(path,pent->d_name);
printf("\n go to directory and remove %s\n",path);
removedir(path);


}

else
{

unlink(pent->d_name);
//printf("Success\n %s", pent->d_name);



}

}




}


//closedir (pdir);



if (!rmdir(pent->d_name)) return -1; // delete the directory */



}






int main()

{

int ret;

char *path_dir=malloc(256);
char path[50];
printf("enter Directory name\n");

scanf("%s",path);

strcpy(path_dir,path);

ret=removedir(path_dir);

printf("\n %d", ret);

return 111;

//else return -1;

}



Thanks,
Ajith

[Rubberman]

In this section of code:

/ printf("\n %s\n" ,pent->d_name);
if(((pent->d_name)==".")||((pent->d_name)==".."))
{
    continue;
}

You continue the loop if the directory is either '.' or '..'; however, the '.' directory is the current directory, so it will continuously loop at that point. I didn't look further, so there may be other problems.

FWIW, if this is a school/class exercise, we are not supposed to help you, other than in the most general terms to point you in a reasonable direction. Please review and abide by the terms of service for the forums.

[ajith_kamath]

I just resolved the error .. had done stack trace using gdb..
Problem was not in "." or ".."
I was path which was not getting reset if the file is deleted or if trace is coming out of some folder

Its not school thingy..

I used to code long time back.. now i m just practising...

Btw here is revised code if anyone wants it :

#include<stdio.h>
#include <dirent.h>
#include <sys/stat.h>

#include<malloc.h>
#include<string.h>
#include <sys/types.h>
#include<errno.h>



int removedir(char path[500])

{


int counter =1;


DIR *pdir = NULL;
struct dirent *pent = NULL;
struct stat eStat;
pdir = opendir(path);
char x[500];


if ( pdir == NULL)
{
return -1;
}

//strcpy(x,path);
while ( (pent=readdir(pdir)) != NULL )
{

// printf("\n %s\n" ,pent->d_name);
if((strcmp((pent->d_name),".")==0)||(strcmp((pent->d_name),"..")==0))
{
printf("Continuing from %s, dname: %s\n",path,pent->d_name);
continue;

}
else
{
printf("Entering first non . or .. file%s , dname: %s\n",path,pent->d_name);
strcpy(x,path);
printf("Current X :%s\n",x);
path=strcat(path,"/");
path=strcat(path,pent->d_name);

if(stat(path, &eStat))
{

printf("ERROR: %s... Meaning it can be a file(Most certainly)\n", strerror(errno));
//unlink(path);
//path=x;

}
else{


if(S_ISDIR(eStat.st_mode))
{

printf("\n go to directory and remove %s\n",path);
removedir(path);
strcpy(path,x);
//rmdir(path);

}
else {

unlink(path);
printf("Unlinked %s\n",path);
strcpy(path,x);
printf("After Unlinking now path = : %s\n",path);
//strcpy(path,x);
}


}


}




}


//closedir (pdir);



if (!rmdir(path)) return -1; // delete the directory */



}






int main()

{

int ret;

char *path_dir=malloc(500);
char path[500];
printf("enter Directory name\n");

scanf("%s",path);

strcpy(path_dir,path);

ret=removedir(path_dir);

printf("\n %d", ret);

return 111;

//else return -1;

}