Prepare entries system call

kernel/include/vfs.hpp

@@ -9,6 +9,7 @@
 #define VFS_H
 
 #include <stat_info.hpp>
+#include <directory_entry.hpp>
 
 //TODO Once userspace is done, integrate parts of disks.hpp here
 
@@ -19,6 +20,7 @@ int64_t stat(size_t fd, stat_info& info);
 int64_t mkdir(const char* file);
 int64_t rm(const char* file);
 int64_t read(size_t fd, char* buffer, size_t max);
+int64_t entries(size_t fd, char* buffer, size_t size);
 
 void close(size_t fd);
 

kernel/src/vfs.cpp

@@ -229,3 +229,56 @@ int64_t vfs::read(size_t fd, char* buffer, size_t max){
 
     return i;
 }
+
+int64_t entries(size_t fd, char* buffer, size_t size){
+    if(!disks::mounted_partition() || !disks::mounted_disk()){
+        return -std::ERROR_NOTHING_MOUNTED;
+    }
+
+    if(!scheduler::has_handle(fd)){
+        return -std::ERROR_INVALID_FILE_DESCRIPTOR;
+    }
+
+    auto path = scheduler::get_handle(fd);
+
+    if(path.empty()){
+        return -std::ERROR_INVALID_FILE_PATH;
+    }
+
+    //TODO file search should be done entirely by the file system
+
+    auto files = fat32::ls(*disks::mounted_disk(), *disks::mounted_partition(), path);
+
+    size_t total_size = 0;
+
+    for(auto& f : files){
+        total_size += sizeof(directory_entry) + f.file_name.size();
+    }
+
+    if(size < total_size){
+        return -std::ERROR_BUFFER_SMALL;
+    }
+
+    size_t position = 0;
+
+    for(size_t i = 0; i < files.size(); ++i){
+        auto& file = files[i];
+
+        auto entry = reinterpret_cast<directory_entry*>(buffer + position);
+
+        entry->type = 0; //TODO Fill that
+        entry->length = file.file_name.size();
+
+        if(i + 1 < files.size()){
+            entry->offset_next = file.file_name.size() + 1;
+        } else {
+            entry->offset_next = 0;
+        }
+
+        char* name_buffer = &(entry->name);
+        for(size_t j = 0; j < file.file_name.size(); ++j){
+            name_buffer[j] = file.file_name[j];
+        }
+        name_buffer[file.file_name.size()] = '\0';
+    }
+}

tlib/include/directory_entry.hpp

@@ -0,0 +1,20 @@
+//=======================================================================
+// Copyright Baptiste Wicht 2013-2014.
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt)
+//=======================================================================
+
+#ifndef USER_DIRECTORY_ENTRY_HPP
+#define USER_DIRECTORY_ENTRY_HPP
+
+#include <types.hpp>
+
+struct directory_entry {
+    size_t type;
+    size_t offset_next;
+    size_t length;
+    char name; //First char
+};
+
+#endif

tlib/include/errors.hpp

@@ -23,6 +23,7 @@ constexpr const size_t ERROR_DIRECTORY = 6;
 constexpr const size_t ERROR_INVALID_FILE_DESCRIPTOR= 7;
 constexpr const size_t ERROR_FAILED= 8;
 constexpr const size_t ERROR_EXISTS= 9;
+constexpr const size_t ERROR_BUFFER_SMALL= 10;
 
 inline const char* error_message(size_t error){
     switch(error){
@@ -44,6 +45,8 @@ inline const char* error_message(size_t error){
             return "Failed";
         case ERROR_EXISTS:
             return "The file exists";
+        case ERROR_BUFFER_SMALL:
+            return "The buffer is too small";
         default:
             return "Unknonwn error";
     }