libos: Add Directory::list()

apps/init.cpp

@@ -239,8 +239,9 @@ static Result<void> load_services()
 {
     auto dir = TRY(os::Directory::open("/etc/init"));
 
-    String entry;
-    while ((entry = TRY(dir->next(os::Directory::Filter::ParentAndBase))), !entry.is_empty())
+    auto services = TRY(dir->list(os::Directory::Filter::ParentAndBase));
+
+    for (const auto& entry : services)
     {
         auto service_path = TRY(PathParser::join("/etc/init"_sv, entry.view()));
         TRY(load_service(service_path.view()));

apps/ls.cpp

@@ -25,13 +25,14 @@ Result<int> luna_main(int argc, char** argv)
     else if (show_all)
         filter = os::Directory::Filter::None;
 
+    auto files = TRY(dir->list(filter));
+
     int first_ent = 1;
-    do {
-        auto ent = TRY(dir->next(filter));
-        if (ent.is_empty()) break;
-        printf(first_ent ? "%s" : " %s", ent.chars());
+    for (const auto& file : files)
+    {
+        printf(first_ent ? "%s" : " %s", file.chars());
         first_ent = 0;
-    } while (1);
+    }
 
     putchar('\n');
 

libc/include/dirent.h

@@ -26,6 +26,7 @@ extern "C"
     struct dirent* readdir(DIR* stream);
     int closedir(DIR* stream);
     int dirfd(DIR* stream);
+    void rewinddir(DIR* stream);
 
 #ifdef __cplusplus
 }

libc/src/dirent.cpp

@@ -66,4 +66,9 @@ extern "C"
     {
         return stream->_fd;
     }
+
+    void rewinddir(DIR* stream)
+    {
+        lseek(stream->_fd, 0, SEEK_SET);
+    }
 }

libos/include/os/Directory.h

@@ -2,6 +2,7 @@
 #include <dirent.h>
 #include <luna/SharedPtr.h>
 #include <luna/String.h>
+#include <luna/Vector.h>
 
 namespace os
 {
@@ -21,6 +22,10 @@ namespace os
 
         Result<String> next(Filter filter);
 
+        Result<Vector<String>> list(Filter filter);
+
+        void rewind();
+
         int fd()
         {
             return dirfd(m_dirp);

libos/src/Directory.cpp

@@ -66,6 +66,23 @@ namespace os
         return String::from_cstring(ent->d_name);
     }
 
+    Result<Vector<String>> Directory::list(Filter filter)
+    {
+        Vector<String> result;
+
+        rewind();
+
+        String entry {};
+        while ((entry = TRY(next(filter))), !entry.is_empty()) TRY(result.try_append(move(entry)));
+
+        return result;
+    }
+
+    void Directory::rewind()
+    {
+        rewinddir(m_dirp);
+    }
+
     Directory::~Directory()
     {
         if (m_dirp) closedir(m_dirp);

libos/src/FileSystem.cpp

@@ -63,16 +63,7 @@ namespace os::FileSystem
 
         auto dir = TRY(os::Directory::openat(dirfd, path));
 
-        Vector<String> entries;
-
-        // FIXME: This is done because the kernel doesn't appreciate us deleting entries while iterating over
-        // directories. This means that we have to iterate first, then delete.
-
-        String ent;
-        while ((ent = TRY(dir->next(os::Directory::Filter::ParentAndBase))), !ent.is_empty())
-        {
-            TRY(entries.try_append(move(ent)));
-        }
+        Vector<String> entries = TRY(dir->list(os::Directory::Filter::ParentAndBase));
 
         for (const auto& entry : entries) { TRY(remove_tree_at(dir->fd(), entry.view())); }