#define _CRT_SECURE_NO_WARNINGS 1
#define NAME_MAX 14
#include <stdio.h>
#include <string.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <unistd.h>

#ifndef DIRSIZE
#define DIRSIZE 14
#endif // !DIRSIZE


typedef struct {
    long ino;
    char name[NAME_MAX + 1];
} Dirent;

typedef struct {
    int fd;
    Dirent d;
} DIR;

DIR* opendir(const char* dirname);
Dirent* readdir(DIR* dfd);
void closedir(DIR* dfd);




void fsize(const char* name);


void dirwalk(const char*, void (*fcn)(const char*));

void fsize(const char* name)
{

    struct stat stbuf;
    if (stat(name, &stbuf) == -1) {
        fprintf(stderr, "fsize: can't access %s\n", name);
        //printf(stderr, "fsize: can't access %s\n", name);
        return;
    }
    /*
    printf("S_IFMT = 0%o\n" ,S_IFMT ) ;
    printf("S_IFDIR = 0%o\n",S_IFDIR) ;
    printf("S_IFCHR = 0%o\n",S_IFCHR) ;
    printf("S_IFBLK = 0%o\n",S_IFBLK) ;
    printf("S_IFREG = 0%o\n",S_IFREG) ;
    
    printf("stbuf.st_mode & S_IFMT = 0%o\n", stbuf.st_mode & S_IFMT);
    */
    
    if ((stbuf.st_mode & S_IFMT) == S_IFDIR) {
    
    dirwalk(name, fsize); }
    //printf("ggg%8ld %s\n", stbuf.st_size, name);

}

#define MAX_PATH 1024

void dirwalk(const char* dir, void (*fcn)(const char*))
{
    char name[MAX_PATH];
    Dirent* dp;
    DIR* dfd;
    if ((dfd = opendir(dir)) == NULL) {
        fprintf(stderr, "dirwalk: can't open %s\n", dir);
              return;
    }
    //printf("%s\n", dir );
     while ((dp = readdir(dfd)) != NULL) {
      
          if (strcmp(dp->name, ".") == 0 || strcmp(dp->name, "..") == 0) continue;
          if (strlen(dir) + strlen(dp->name) + 2 > sizeof(name))
              fprintf(stderr, "dirwalk: name %s %s too long\n", dir, dp->name);
              //printf(stderr, "dirwalk: name %s %s too long\n", dir, dp->name);
          else {
              sprintf(name, "%s/%s", dir, dp->name);
              (*fcn)(name);
          }
      }
      closedir(dfd);
}

struct direct
{
    ino_t d_ino;
    char d_name[DIRSIZE];
};



DIR* opendir(const char* dirname)
{
    int fd;
    struct stat stbuf;
    DIR* dp;
        if ((fd = open(dirname, O_RDONLY, 0)) == -1
            || fstat(fd, &stbuf) == -1
            || (stbuf.st_mode & S_IFMT) != S_IFDIR
            || (dp = (DIR*)malloc(sizeof(DIR))) == NULL) 
                        return NULL;
        dp->fd = fd;
      
        return dp;
}

Dirent * readdir(DIR* dp)
{
    struct direct dirbuf;
    static Dirent d;
          char test[50];
    int y=read(dp->fd, test, sizeof(dirbuf)) ;
     printf("read bytes=%d \n",y);
     int x=read(dp->fd, (char*)&dirbuf, sizeof(dirbuf));
     printf("read bytes=%d \n",x);          
    while (read(dp->fd, (char*)&dirbuf, sizeof(dirbuf)) == sizeof(dirbuf))
    {

        if (dirbuf.d_ino == 0) continue;
        d.ino = dirbuf.d_ino;
        strncpy(d.name, dirbuf.d_name, DIRSIZE);
        d.name[DIRSIZE] = '\0';
        return &d;
    }
    return NULL;
}
void closedir(DIR* dp)
{
    if (dp) {
        close(dp->fd);
        free(dp);
    }
}


int main(int argc, char** argv)
{

      if (argc == 1) fsize(".");
      else
      { 
          while (--argc > 0)
              fsize(*++argv);
    }
    return 0;
}