Optimize DirAccessUnix::get_next() for some file systems

On some file systems, like ext4 on Linux, readdir() gives enough
information to determine the entry type in order to avoid doing
a stat() system call.

Use this information and call stat() only if necessary: for file
systems that do not support this feature and for links.
This commit is contained in:
Hadrien 2019-07-29 08:04:22 +02:00
parent 331a703f5d
commit e02c5ef48a

View file

@ -126,37 +126,32 @@ String DirAccessUnix::get_next() {
if (!dir_stream)
return "";
dirent *entry;
entry = readdir(dir_stream);
dirent *entry = readdir(dir_stream);
if (entry == NULL) {
list_dir_end();
return "";
}
//typedef struct stat Stat;
struct stat flags;
String fname = fix_unicode_name(entry->d_name);
String f = current_dir.plus_file(fname);
if (stat(f.utf8().get_data(), &flags) == 0) {
if (S_ISDIR(flags.st_mode)) {
_cisdir = true;
// Look at d_type to determine if the entry is a directory, unless
// its type is unknown (the file system does not support it) or if
// the type is a link, in that case we want to resolve the link to
// known if it points to a directory. stat() will resolve the link
// for us.
if (entry->d_type == DT_UNKNOWN || entry->d_type == DT_LNK) {
String f = current_dir.plus_file(fname);
struct stat flags;
if (stat(f.utf8().get_data(), &flags) == 0) {
_cisdir = S_ISDIR(flags.st_mode);
} else {
_cisdir = false;
}
} else {
_cisdir = false;
_cisdir = (entry->d_type == DT_DIR);
}
_cishidden = (fname != "." && fname != ".." && fname.begins_with("."));