ls -l の実装

kernel/fat.cpp

@@ -66,6 +66,34 @@ void FormatName(const DirectoryEntry& entry, char* dest) {
   }
 }
 
+void FormatWriteTime(const DirectoryEntry& entry, char* dest) {
+  int year = ((entry.write_date >> 9) & 0x3f) + 1980;
+  int month = (entry.write_date >> 5) & 0xf;
+  int date = entry.write_date & 0x1f;
+  int hour = (entry.write_time >> 11) & 0x1f;
+  int minute = (entry.write_time >> 5) & 0x3f;
+  int second = (entry.write_time & 0x1f) * 2;
+
+  auto int_to_str = [](char* out, int value, int num_digits) {
+    for (int i = 0; i < num_digits; i++) {
+      out[num_digits - 1 - i] = '0' + (value % 10);
+      value /= 10;
+    }
+  };
+  int_to_str(&dest[0], year, 4);
+  dest[4] = '-';
+  int_to_str(&dest[5], month, 2);
+  dest[7] = '-';
+  int_to_str(&dest[8], date, 2);
+  dest[10] = ' ';
+  int_to_str(&dest[11], hour, 2);
+  dest[13] = ':';
+  int_to_str(&dest[14], minute, 2);
+  dest[16] = ':';
+  int_to_str(&dest[17], second, 2);
+  dest[19] = '\0';
+}
+
 unsigned long NextCluster(unsigned long cluster) {
   uint32_t next = GetFAT()[cluster];
   if (IsEndOfClusterchain(next)) {

kernel/fat.hpp

@@ -112,6 +112,14 @@ void ReadName(const DirectoryEntry& entry, char* base, char* ext);
  */
 void FormatName(const DirectoryEntry& entry, char* dest);
 
+/** @brief ディレクトリエントリの更新日時を dest にコピーする。
+ * 日時は "YYYY-MM-DD hh:mm:ss" 形式で表現する。
+ *
+ * @param entry  更新日時を得る対象のディレクトリエントリ
+ * @param dest  更新日時を表現する文字列を格納するに十分な大きさの配列。
+ */
+void FormatWriteTime(const DirectoryEntry& entry, char* dest);
+
 static const unsigned long kEndOfClusterchain = 0x0ffffffflu;
 
 /** @brief 指定されたクラスタの次のクラスタ番号を返す。

kernel/terminal.cpp

@@ -149,7 +149,7 @@ Error FreePML4(Task& current_task) {
   return FreePageMap(reinterpret_cast<PageMapEntry*>(cr3));
 }
 
-void ListAllEntries(FileDescriptor& fd, uint32_t dir_cluster) {
+void ListAllEntries(FileDescriptor& fd, uint32_t dir_cluster, bool verbose) {
   const auto kEntriesPerCluster =
     fat::bytes_per_cluster / sizeof(fat::DirectoryEntry);
 
@@ -165,6 +165,16 @@ void ListAllEntries(FileDescriptor& fd, uint32_t dir_cluster) {
         continue;
       }
 
+      if (verbose) {
+        if ((uint8_t)dir[i].attr & (uint8_t)fat::Attribute::kDirectory) {
+          PrintToFD(fd, "%10s", "<DIR>");
+        } else {
+          PrintToFD(fd, "%10lu", (unsigned long)dir[i].file_size);
+        }
+        char date[20];
+        fat::FormatWriteTime(dir[i], date);
+        PrintToFD(fd, " %s ", date);
+      }
       char name[13];
       fat::FormatName(dir[i], name);
       PrintToFD(fd, "%s\n", name);
@@ -447,22 +457,40 @@ void Terminal::ExecuteLine() {
           dev.class_code.base, dev.class_code.sub, dev.class_code.interface);
     }
   } else if (strcmp(command, "ls") == 0) {
-    if (!first_arg || first_arg[0] == '\0') {
-      ListAllEntries(*files_[1], fat::boot_volume_image->root_cluster);
+    char* file_name = first_arg;
+    bool verbose = false;
+    if (file_name && file_name[0] == '-') {
+      for (++file_name; *file_name && !isspace(*file_name); ++file_name) {
+        if (*file_name == 'l') verbose = true;
+      }
+      while (isspace(*file_name)) file_name++;
+    }
+    if (!file_name || file_name[0] == '\0') {
+      ListAllEntries(*files_[1], fat::boot_volume_image->root_cluster, verbose);
     } else {
-      auto [ dir, post_slash ] = fat::FindFile(first_arg);
+      auto [ dir, post_slash ] = fat::FindFile(file_name);
       if (dir == nullptr) {
-        PrintToFD(*files_[2], "No such file or directory: %s\n", first_arg);
+        PrintToFD(*files_[2], "No such file or directory: %s\n", file_name);
         exit_code = 1;
       } else if (dir->attr == fat::Attribute::kDirectory) {
-        ListAllEntries(*files_[1], dir->FirstCluster());
+        ListAllEntries(*files_[1], dir->FirstCluster(), verbose);
       } else {
         char name[13];
         fat::FormatName(*dir, name);
         if (post_slash) {
           PrintToFD(*files_[2], "%s is not a directory\n", name);
           exit_code = 1;
         } else {
+          if (verbose) {
+            if ((uint8_t)dir->attr & (uint8_t)fat::Attribute::kDirectory) {
+              PrintToFD(*files_[1], "%10s", "<DIR>");
+            } else {
+              PrintToFD(*files_[1], "%10lu", (unsigned long)dir->file_size);
+            }
+            char date[20];
+            fat::FormatWriteTime(*dir, date);
+            PrintToFD(*files_[1], " %s ", date);
+          }
           PrintToFD(*files_[1], "%s\n", name);
         }
       }