Let's Rewrite Linux 'ls' command: Getting the list of files and their info

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <dirent.h>

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

    DIR *dir;            // for reading directory
    struct dirent *file; // struct for getting file data

    dir = opendir("folder");

    while ((file = readdir(dir)) != NULL)
        printf("%s\n", file->d_name);

    return 0;
}

typedef struct
{
    struct stat;
    char name[256];
    char permission[11];
    char color[16];
    char extension[256];
    char indicator; // for -F and -p
    char owner_name[256];
    char group_name[256];

} file_info;

#include <stdio.h>
#include <dirent.h>
#include <options.h>
#include <file.h>
#include <unistd.h>

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

    DIR *dir;            // for reading directory
    struct dirent *file; // struct for getting file data
    file_info files;

    chdir("folder");
    dir = opendir(".");

    while ((file = readdir(dir)) != NULL)
    {
        stat(file->d_name, (struct stat *)&files);
        printf("%s %d\n", file->d_name, files.st_size);
    }

    return 0;
}

. 174
.. 188
folder1 66
archive.tar.xz 23734296
block1 0
charfile1 0
exe1 0
hlink1 0
file1 0
socket1 0
slink1 0
pipe1 0
.hiddenfile 0

void get_username_from_uid(int uid, char *username)
{
    struct passwd *pws;
    pws = getpwuid(uid);

    strncpy(username, pws->pw_name, 256);
}

void get_groupname_from_gid(int gid, char *groupname)
{
    struct group *grp;
    grp = getgrgid(gid);

    strncpy(groupname, grp->gr_name, 256);
}

void construct_permission_str(mode_t mode, char *permission)
{
    // Get the first character from file type
    if      (S_ISREG(mode)) permission[0] = '-';
    else if (S_ISDIR(mode)) permission[0] = 'd';
    else if (S_ISLNK(mode)) permission[0] = 'l';
    else if (S_ISCHR(mode)) permission[0] = 'c';
    else if (S_ISBLK(mode)) permission[0] = 'b';
    else if (S_ISSOCK(mode)) permission[0] = 's';
    else if (S_ISFIFO(mode)) permission[0] = 'p';

    permission[1] = (mode & S_IRUSR) ? 'r' : '-';
    permission[2] = (mode & S_IWUSR) ? 'w' : '-';
    permission[3] = (mode & S_IXUSR) ? 'x' : '-';
    
    permission[4] = (mode & S_IRGRP) ? 'r' : '-';
    permission[5] = (mode & S_IWGRP) ? 'w' : '-';
    permission[6] = (mode & S_IXGRP) ? 'x' : '-';

    permission[7] = (mode & S_IROTH) ? 'r' : '-';
    permission[8] = (mode & S_IWOTH) ? 'w' : '-';
    permission[9] = (mode & S_IXOTH) ? 'x' : '-';
    permission[10] = 0;  // terminator char, just in case
}

void get_file_extension(char *file_name, char *extension)
{
    char *p = strrchr(file_name, '.');
    
    if (p)
        strcpy(extension, strrchr(file_name, '.'));
}

#define COLOR_RESET         "\x1b[0m" // reset color settings
#define COLOR_REGULAR       COLOR_RESET
#define COLOR_EXECUTABLES   "\x1b[1;32m"
#define COLOR_DIRECTORIES   "\x1b[1;34m"
#define COLOR_LINK          "\x1b[1;36m"
#define COLOR_FIFO          "\x1b[40;33m"
#define COLOR_SOCKET        "\x1b[1;35m"
#define COLOR_BLK_CHR       "\x1b[40;33;1m"
#define COLOR_BROKEN_LINK   "\x1b[40;31;1m"
#define COLOR_ARCHIVE       "\x1b[1;31m"

void get_color(char* permission, char *extension, char *color)
{
    switch (permission[0])
    {
    case '-':
        if (permission[3] == 'x' || permission[6] == 'x' || permission[9] == 'x')
            strcpy(color, COLOR_EXECUTABLES);
        else if (is_archive_file(extension))
            strcpy(color, COLOR_ARCHIVE);
        else
            strcpy(color, COLOR_REGULAR);
        break;
    case 'd':
        strcpy(color, COLOR_DIRECTORIES);
        break;
    case 'l':
        strcpy(color, COLOR_LINK);
        break;
    case 'c':
    case 'b':
        strcpy(color, COLOR_BLK_CHR);
        break;
    case 's':
        strcpy(color, COLOR_SOCKET);
        break;
    case 'p':
        strcpy(color, COLOR_FIFO);
        break;
    default:
        break;
    }
}

char get_indicator(char* permission)
{
    switch (permission[0])
    {
    case '-':
        if (permission[3] == 'x' || permission[6] == 'x' || permission[9] == 'x')
            return '*';
        
        return ' '; 
    case 'd':
        return '/';
    case 'l':
        return '@';
    case 's':
        return '=';
    case 'p':
        return '|';
    default:
        return ' ';
    }
}

#include <stdio.h>
#include <dirent.h>
#include <options.h>
#include <file_data.h>
#include <unistd.h>
#include <string.h>
#include <time.h>

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

    DIR *dir;            // for reading directory
    struct dirent *file; // struct for getting file data
    file_info files[256];  // For now static array

    chdir("folder");
    dir = opendir(".");
    int i = 0;

    while ((file = readdir(dir)) != NULL)
    {
        lstat(file->d_name, (struct stat *)&files[i]);

        strncpy(files[i].name, file->d_name, 256);
        get_username_from_uid(files[i].st_uid, files[i].owner_name);
        get_groupname_from_gid(files[i].st_gid, files[i].group_name);
        construct_permission_str(files[i].st_mode, files[i].permission);
        get_file_extension(files[i].name, files[i].extension);
        get_color(files[i].permission, files[i].extension, files[i].color);
        
        files[i].indicator = get_indicator(files[i].permission);
        ++i;
    }

    char filetime[20];
    struct tm *timeinfo;

    for (int j = 0; j < i; ++j)
    {
        timeinfo = localtime(&files[j].st_mtime);
        strftime(filetime, 20, "%b %-2d %H:%M", timeinfo);

        printf("%9d %5d %s %d %-8s %-7s %8d %s %s%s%s\n", files[j].st_ino, files[j].st_blocks / 2, files[j].permission, files[j].st_nlink, 
                                                    files[j].owner_name, files[j].group_name, files[j].st_size, filetime, files[j].color, files[j].name, COLOR_RESET);
    }

    return 0;
}