improve ls command

src/commands/ls.c

@@ -6,6 +6,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <sys/stat.h>
+#include <sys/ioctl.h>
 #include <unistd.h>
 #include <dirent.h>
 #include <ftw.h>
@@ -26,6 +27,28 @@ struct Flags {
     bool recurse;
 };
 
+struct FileInfo {
+    char mode[11];
+    int links;
+    struct passwd* usr;
+    struct group* grp;
+    char size[5];
+    char date[13];
+    struct dirent* file;
+    bool set_uid;
+    bool set_gid;
+    bool exec;
+};
+
+struct FileListInfo {
+    int max_link;
+    int max_usr;
+    int max_grp;
+    int max_size;
+    int max_name;
+    int total_len;
+};
+
 static DIR* get_directory(char* path) {
     DIR* d = opendir(path);
     if (d == NULL) {
@@ -44,114 +67,152 @@ static void append_path(char buf[PATH_MAX], const char* dir_path, const struct d
     memcpy(buf + dir_len, file->d_name, strlen(file->d_name) + 1);
 }
 
-static void list_file(struct dirent* file, struct Flags* flags, const char* dir_path) {
+static bool get_file_info(struct dirent* file, const char* dir_path, struct FileInfo* info) {
 
-    char* color;
+    uid_t uid = getuid();
+    gid_t gid = getgid();
 
-    if (file->d_type == DT_DIR) {
+    char buf[PATH_MAX];
-        color = DIR_COLOR;
+    append_path(buf, dir_path, file);
-    } else if (file->d_type == DT_LNK) {
+        
-        color = LINK_COLOR;
+    struct stat s;
-    } else {
+    if (stat(buf, &s) < 0) {
-        color = FILE_COLOR;
+        printf("\x1b[0merror: failed to read file '%s': %s\n", buf, strerror(errno));
+        return false;
     }
 
-    if (flags->more_info) {
+    info->set_uid = false;
+    info->set_gid = false;
+    info->exec = false;
 
-        uid_t uid = getuid();
+    if (file->d_type == DT_DIR) 
-        gid_t gid = getgid();
+        info->mode[0] = 'd';
+    else if (file->d_type == DT_LNK) 
+        info->mode[0] = 'l';
+    else 
+        info->mode[0] = '-';
 
-        char buf[PATH_MAX];
+    info->mode[1] = (s.st_mode & S_IRUSR) ? 'r' : '-';
-        append_path(buf, dir_path, file);
+    info->mode[2] = (s.st_mode & S_IWUSR) ? 'w' : '-';
-        
+    if (s.st_mode & S_IXUSR) {
-        struct stat s;
+        if (s.st_mode & S_ISUID) {
-        if (stat(buf, &s) < 0) {
+            info->mode[3] = 's';
-            printf("\x1b[0merror: failed to read file '%s': %s\n", buf, strerror(errno));
+            info->set_uid = true;
-            return;
-        }
-
-        if (file->d_type == DT_DIR) putchar('d');
-        else if (file->d_type == DT_LNK) putchar('l');
-        else putchar('-');
-
-        bool group_sticky = false;
-        bool user_sticky = false;
-        bool exectuable = false;
-
-        putchar((s.st_mode & S_IRUSR) ? 'r' : '-');
-        putchar((s.st_mode & S_IWUSR) ? 'w' : '-');
-        if (s.st_mode & S_IXUSR) {
-            if (putchar(s.st_mode & S_ISUID)) {
-                putchar('s');
-                user_sticky = true;
-            } else {
-                putchar('x');
-            }
-            if (!exectuable) exectuable = s.st_uid == uid;
         } else {
-            putchar('-');
+            info->mode[3] = 'x';
         }
-
+        if (!info->exec) info->exec = s.st_uid == uid;
-        putchar((s.st_mode & S_IRGRP) ? 'r' : '-');
-        putchar((s.st_mode & S_IWGRP) ? 'w' : '-');
-        if (s.st_mode & S_IXGRP) {
-            if (putchar(s.st_mode & S_ISGID)) {
-                putchar('s');
-                group_sticky = true;
-            } else {
-                putchar('x');
-            }
-            if (!exectuable) exectuable = s.st_gid == gid;
-        } else {
-            putchar('-');
-        }
-
-        putchar((s.st_mode & S_IROTH) ? 'r' : '-');
-        putchar((s.st_mode & S_IWOTH) ? 'w' : '-');
-        if (s.st_mode & S_IXOTH) {
-            putchar('x');
-            exectuable = true;
-        } else {
-            putchar('-');
-        }
-
-        printf(" %ld\t", s.st_nlink);
-
-        struct passwd* passwd = getpwuid(s.st_uid);
-        struct group* group = getgrgid(s.st_gid);
-
-        printf("%s ", passwd->pw_name);
-        printf("%s ", group->gr_name);
-
-        print_file_size(s.st_size);
-        print_date_time(s.st_mtim.tv_sec + s.st_mtim.tv_nsec / 1000000);
-
-        if (file->d_type == DT_REG) {
-            if (user_sticky) {
-                color = SET_UID_COLOR;
-            } else if (group_sticky) {
-                color = SET_GID_COLOR;
-            } else if (exectuable) {
-                color = EXEC_COLOR;
-            }
-        }
-
-        printf("%s%s\x1b[0m", color, file->d_name);
-
-        if (file->d_type == DT_LNK) {
-            char link[PATH_MAX];
-            if (readlink(buf, link, PATH_MAX) < 0) {
-                printf("\n");
-            } else {
-                printf(" -> %s\n", link);
-            }
-        } else {
-            printf("\n");
-        }
-        
     } else {
-        printf("%s%s", color, file->d_name);
+        info->mode[3] = '-';
-        flags->one_column ? putchar('\n') : putchar(' ');
+    }
+
+    info->mode[4] = (s.st_mode & S_IRGRP) ? 'r' : '-';
+    info->mode[5] = (s.st_mode & S_IWGRP) ? 'w' : '-';
+    if (s.st_mode & S_IXGRP) {
+        if (s.st_mode & S_ISGID) {
+            info->mode[6] = 's';
+            info->set_gid = true;
+        } else {
+            info->mode[6] = 'x';
+        }
+        if (!info->exec) info->exec = s.st_gid == gid;
+    } else {
+        info->mode[6] = '-';
+    }
+
+    info->mode[7] = (s.st_mode & S_IROTH) ? 'r' : '-';
+    info->mode[8] = (s.st_mode & S_IWOTH) ? 'w' : '-';
+    if (s.st_mode & S_IXOTH) {
+        info->mode[9] = 'x';
+        info->exec = true;
+    } else {
+        info->mode[9] = '-';
+    }
+
+    info->mode[10] = '\0';
+
+    info->usr = getpwuid(s.st_uid);
+    info->grp = getgrgid(s.st_gid);
+    info->file = file;
+    info->links = s.st_nlink;
+
+    print_file_size(s.st_size, info->size);
+    print_date_time(s.st_mtim.tv_sec + s.st_mtim.tv_nsec / 1000000, info->date);
+    return true;
+}
+
+static char* get_file_color(struct FileInfo* info) {
+    char* color;
+    if (info->file->d_type == DT_DIR) {
+        color = DIR_COLOR;
+    } else if (info->file->d_type == DT_LNK) {
+        color = LINK_COLOR;
+    } else {
+        if (info->set_uid) {
+            color = SET_UID_COLOR;
+        } else if (info->set_gid) {
+            color = SET_GID_COLOR;
+        } else if (info->exec) {
+            color = EXEC_COLOR;
+        } else {
+            color = FILE_COLOR;
+        }
+    }
+    return color;
+}
+
+static void list_files(struct FileInfo* files, int file_len, struct FileListInfo info, struct Flags* flags, const char* dir_path) {
+
+    struct winsize w;
+    ioctl(STDOUT_FILENO, TIOCGWINSZ, &w);
+
+    char* color;
+    const int column_width = info.max_name + 1;
+    const int row_count = w.ws_col / column_width;
+
+    for (int i = 0; i < file_len; i++) {
+        struct FileInfo finfo = files[i];
+        if (strlen(finfo.file->d_name) < 1) continue;
+        color = get_file_color(&finfo);
+        if (flags->more_info) {
+            printf("%s %*d %*s %*s %*s %s %s%s\x1b[0m", 
+                finfo.mode, 
+                info.max_link,
+                finfo.links,
+                info.max_usr,
+                finfo.usr->pw_name,
+                info.max_grp,
+                finfo.grp->gr_name, 
+                info.max_size,
+                finfo.size, 
+                finfo.date,
+                color,
+                finfo.file->d_name
+            );
+            if (finfo.file->d_type == DT_LNK) {
+                char path[PATH_MAX];
+                append_path(path, dir_path, finfo.file);
+
+                char lnk[PATH_MAX];
+                if (readlink(path, lnk, PATH_MAX) < 0) {
+                    putchar('\n');
+                } else {
+                    printf(" -> %s\n", lnk);
+                }
+            
+            } else {
+                putchar('\n');
+            }
+        } else if (flags->one_column) {
+            printf("%s%s\x1b[0m\n", color, finfo.file->d_name);
+        } else {
+            if (info.total_len > w.ws_col) {
+                if (i != 0 && i % row_count == 0) putchar('\n');
+                printf("%s%*s\x1b[0m", color, column_width, finfo.file->d_name);
+            } else {
+                printf("%s%s\x1b[0m  ", color, finfo.file->d_name);
+            }
+        }
     }
 }
 
@@ -159,6 +220,53 @@ static bool is_dot_dir(const char* path) {
     return streql(path, ".") || streql(path, "..");
 }
 
+static int num_places (int n) {
+    int r = 1;
+    if (n < 0) n = (n == INT_MIN) ? INT_MAX: -n;
+    while (n > 9) {
+        n /= 10;
+        r++;
+    }
+    return r;
+}
+
+static void push_file(
+    struct FileInfo** files, 
+    struct FileListInfo* info, 
+    int* size, int* capacity, 
+    struct dirent* file, 
+    const char* dir_path
+) {
+
+    struct FileInfo finfo;
+    if (!get_file_info(file, dir_path, &finfo)) return;
+
+    if (*size == *capacity) {
+        *capacity *= 2;
+        *files = realloc(*files, sizeof(struct FileInfo) * *capacity);
+    }
+
+    int user_len = strlen(finfo.usr->pw_name);
+    if (user_len > info->max_usr) info->max_usr = user_len;
+
+    int group_len = strlen(finfo.grp->gr_name);
+    if (group_len > info->max_grp) info->max_grp = group_len;
+
+    int name_len = strlen(file->d_name);
+    if (name_len > info->max_name) info->max_name = name_len;
+
+    int size_len = strlen(finfo.size);
+    if (size_len > info->max_size) info->max_size = size_len;
+
+    int link_len = num_places(finfo.links);
+    if (link_len > info->max_link) info->max_link = link_len;
+
+    info->total_len += name_len + 2;
+
+    (*files)[*size] = finfo;
+    (*size)++;
+}
+
 static void recurse_directory(char* path, struct Flags* flags) {
     DIR* d;
     struct dirent* file;
@@ -167,6 +275,12 @@ static void recurse_directory(char* path, struct Flags* flags) {
     d = get_directory(path);
     if (d == NULL) return;
 
+    int capacity = 8;
+    int size = 0;
+    struct FileInfo* files = malloc(sizeof(struct FileInfo) * capacity);
+    struct FileListInfo info;
+    memset(&info, 0, sizeof(struct FileListInfo));
+
     while((file = readdir(d)) != NULL) {
         if (file->d_type == DT_DIR) continue;
         if (!flags->hidden && prefix(".", file->d_name)) continue;
@@ -175,8 +289,11 @@ static void recurse_directory(char* path, struct Flags* flags) {
             printf("\n%s%s:%s\n", DIR_COLOR, path, FILE_COLOR);
             first = false;
         }
-        list_file(file, flags, path);
+        push_file(&files, &info, &size, &capacity, file, path);
     }
+    
+    list_files(files, size, info, flags, path);
+    free(files);
 
     if (!flags->more_info) printf("\n");
 
@@ -206,14 +323,22 @@ static void list_directory(char* path, struct Flags* flags) {
     DIR* d = get_directory(path);
     if (d == NULL) return;
 
+    int capacity = 8;
+    int size = 0;
+    struct FileInfo* files = malloc(sizeof(struct FileInfo) * capacity);
+    struct FileListInfo info;
+    memset(&info, 0, sizeof(struct FileListInfo));
+    
     struct dirent* file;
-
     while ((file = readdir(d)) != NULL) {
         if (!flags->hidden && prefix(".", file->d_name)) continue;
         if (flags->hide_dot && is_dot_dir(file->d_name)) continue;
-        list_file(file, flags, path);
+        push_file(&files, &info, &size, &capacity, file, path);
     }
 
+    list_files(files, size, info, flags, path);
+    free(files);
+    
     closedir(d);
 }
 

src/shared.c

@@ -47,7 +47,7 @@ bool prefix(const char* pre, const char* str) {
 }
 
 static char fs_types[5] = {'K','M','G','T','P'};
-void print_file_size(size_t bytes) {
+void print_file_size(size_t bytes, char buf[5]) {
     int index = 0;
     float next = bytes;
     while (true) {
@@ -61,25 +61,26 @@ void print_file_size(size_t bytes) {
         next /= 1024;
         index++;
     }
-
+    
-    if (next/100 < 1) putchar(' ');
+    int n = snprintf(buf, 4, "%u", (int)(next+.5));
-    if (next/10 < 1) putchar(' ');
-    if (index == 0) putchar(' ');
-
-    printf("%u", (int)(next+.5));
     if (index > 0) {
-        putchar(fs_types[index - 1]);
+        buf[n] = (fs_types[index - 1]);
+        n++;
     }
-    putchar(' ');
+    buf[n] = '\0';
 }
 
 static char* months[12] = 
     {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
-void print_date_time(time_t mills) {
+void print_date_time(time_t mills, char buf[13]) {
     struct tm* info;
     info = localtime(&mills);
-    printf("%s ", months[info->tm_mon]);
+    int n = snprintf(buf, 5, "%s ", months[info->tm_mon]);
-    if (info->tm_mday < 10)
+
-        printf(" ");
+    if (info->tm_mday < 10) {
-    printf("%d %02d:%02d ", info->tm_mday, info->tm_hour, info->tm_sec);
+        buf[n] = ' ';
+        n++;
+    }
+
+    snprintf(buf + n, 13 - n, "%d %02d:%02d ", info->tm_mday, info->tm_hour, info->tm_sec);
 }

src/shared.h

@@ -13,5 +13,5 @@ long int get_number(const char* text);
 bool streql(const char* a, const char* b);
 bool prefix(const char* pre, const char* str);
 
-void print_file_size(size_t bytes);
+void print_file_size(size_t bytes, char buf[5]);
-void print_date_time(time_t mills);
+void print_date_time(time_t mills, char buf[13]);