LibCore: Add CDirIterator, and use it in everything rather than readdir

LibCore/CDirIterator.cpp

@@ -0,0 +1,68 @@
+#include "CDirIterator.h"
+#include <cerrno>
+
+CDirIterator::CDirIterator(const String& path, Flags flags)
+ : m_flags(flags)
+{
+ m_dir = opendir(path.characters());
+ if (m_dir == nullptr) {
+ m_error = errno;
+ }
+}
+
+CDirIterator::~CDirIterator()
+{
+ if (m_dir != nullptr) {
+ closedir(m_dir);
+ m_dir = nullptr;
+ }
+}
+
+bool CDirIterator::advance_next()
+{
+ if (m_dir == nullptr)
+ return false;
+
+ bool keep_advancing = true;
+ while (keep_advancing) {
+ errno = 0;
+ auto* de = readdir(m_dir);
+ if (de) {
+ m_next = de->d_name;
+ } else {
+ m_error = errno;
+ m_next = String();
+ }
+
+ if (m_next.is_null()) {
+ keep_advancing = false;
+ } else if (m_flags & Flags::SkipDots) {
+ if (m_next.length() < 1 || m_next[0] != '.') {
+ keep_advancing = false;
+ }
+ } else {
+ keep_advancing = false;
+ }
+ }
+
+ return m_next.length() > 0;
+}
+
+bool CDirIterator::has_next()
+{
+ if (!m_next.is_null())
+ return true;
+
+ return advance_next();
+}
+
+String CDirIterator::next_path()
+{
+ if (m_next.is_null())
+ advance_next();
+
+ auto tmp = m_next;
+ m_next = String();
+ return tmp;
+}
+

LibCore/CDirIterator.h

@@ -0,0 +1,30 @@
+#pragma once
+
+#include <dirent.h>
+#include <AK/AKString.h>
+
+class CDirIterator {
+public:
+ enum Flags {
+ NoFlags = 0x0,
+ SkipDots = 0x1,
+ };
+
+ CDirIterator(const String& path, Flags = Flags::NoFlags);
+ ~CDirIterator();
+
+ bool has_error() const { return m_error != 0; }
+ int error() const { return m_error; }
+ const char* error_string() const { return strerror(m_error); }
+ bool has_next();
+ String next_path();
+
+private:
+ DIR* m_dir = nullptr;
+ int m_error = 0;
+ String m_next;
+ int m_flags;
+
+ bool advance_next();
+};
+

LibCore/Makefile

@@ -18,7 +18,8 @@ OBJS = \
  CEventLoop.o \
  CConfigFile.o \
  CEvent.o \
- CProcessStatisticsReader.o
+ CProcessStatisticsReader.o \
+ CDirIterator.o
 
 LIBRARY = libcore.a
 DEFINES += -DUSERLAND

LibGUI/GDirectoryModel.cpp

@@ -9,6 +9,7 @@
 #include <SharedGraphics/GraphicsBitmap.h>
 #include <LibGUI/GPainter.h>
 #include <LibCore/CLock.h>
+#include <LibCore/CDirIterator.h>
 
 static CLockable<HashMap<String, RetainPtr<GraphicsBitmap>>>& thumbnail_cache()
 {
@@ -235,22 +236,23 @@ GVariant GDirectoryModel::data(const GModelIndex& index, Role role) const
 
 void GDirectoryModel::update()
 {
- DIR* dirp = opendir(m_path.characters());
- if (!dirp) {
- perror("opendir");
+ CDirIterator di(m_path, CDirIterator::SkipDots);
+ if (di.has_error()) {
+ fprintf(stderr, "CDirIterator: %s\n", di.error_string());
  exit(1);
  }
+
  m_directories.clear();
  m_files.clear();
 
  m_bytes_in_files = 0;
- while (auto* de = readdir(dirp)) {
+ while (di.has_next()) {
+ String name = di.next_path();
  Entry entry;
- entry.name = de->d_name;
- if (entry.name == "." || entry.name == "..")
- continue;
+ entry.name = name;
+
  struct stat st;
- int rc = lstat(String::format("%s/%s", m_path.characters(), de->d_name).characters(), &st);
+ int rc = lstat(String::format("%s/%s", m_path.characters(), name.characters()).characters(), &st);
  if (rc < 0) {
  perror("lstat");
  continue;
@@ -266,7 +268,6 @@ void GDirectoryModel::update()
  if (S_ISREG(entry.mode))
  m_bytes_in_files += st.st_size;
  }
- closedir(dirp);
 
  did_update();
 }

LibGUI/GFileSystemModel.cpp

@@ -1,4 +1,5 @@
 #include <LibGUI/GFileSystemModel.h>
+#include <LibCore/CDirIterator.h>
 #include <AK/FileSystemPath.h>
 #include <AK/StringBuilder.h>
 #include <sys/stat.h>
@@ -33,29 +34,28 @@ struct GFileSystemModel::Node {
  has_traversed = true;
 
  auto full_path = this->full_path(model);
- DIR* dirp = opendir(full_path.characters());
- if (!dirp)
+ CDirIterator di(full_path, CDirIterator::SkipDots);
+ if (di.has_error()) {
+ fprintf(stderr, "CDirIterator: %s\n", di.error_string());
  return;
+ }
 
- while (auto* de = readdir(dirp)) {
- if (!strcmp(de->d_name, ".") || !strcmp(de->d_name, ".."))
- continue;
+ while (di.has_next()) {
+ String name = di.next_path();
  struct stat st;
- int rc = lstat(String::format("%s/%s", full_path.characters(), de->d_name).characters(), &st);
+ int rc = lstat(String::format("%s/%s", full_path.characters(), name.characters()).characters(), &st);
  if (rc < 0) {
  perror("lstat");
  continue;
  }
  if (model.m_mode == DirectoriesOnly && !S_ISDIR(st.st_mode))
  continue;
  auto* child = new Node;
- child->name = de->d_name;
+ child->name = name;
  child->type = S_ISDIR(st.st_mode) ? Node::Type::Directory : Node::Type::File;
  child->parent = this;
  children.append(child);
  }
-
- closedir(dirp);
  }
 
  void reify_if_needed(const GFileSystemModel& model)

LibGUI/GFontDatabase.cpp

@@ -1,4 +1,5 @@
 #include <LibGUI/GFontDatabase.h>
+#include <LibCore/CDirIterator.h>
 #include <SharedGraphics/Font.h>
 #include <dirent.h>
 #include <stdio.h>
@@ -15,15 +16,14 @@ GFontDatabase& GFontDatabase::the()
 
 GFontDatabase::GFontDatabase()
 {
- DIR* dirp = opendir("/res/fonts");
- if (!dirp) {
- perror("opendir");
+ CDirIterator di("/res/fonts", CDirIterator::SkipDots);
+ if (di.has_error()) {
+ fprintf(stderr, "CDirIterator: %s\n", di.error_string());
  exit(1);
  }
- while (auto* de = readdir(dirp)) {
- if (de->d_name[0] == '.')
- continue;
- auto path = String::format("/res/fonts/%s", de->d_name);
+ while (di.has_next()) {
+ String name = di.next_path();
+ auto path = String::format("/res/fonts/%s", name.characters());
  if (auto font = Font::load_from_file(path)) {
  Metadata metadata;
  metadata.path = path;
@@ -32,7 +32,6 @@ GFontDatabase::GFontDatabase()
  m_name_to_metadata.set(font->name(), move(metadata));
  }
  }
- closedir(dirp);
 }
 
 GFontDatabase::~GFontDatabase()

Userland/ls.cpp

@@ -10,6 +10,7 @@
 #include <sys/stat.h>
 #include <AK/AKString.h>
 #include <AK/Vector.h>
+#include <LibCore/CDirIterator.h>
 
 static int do_file_system_object_long(const char* path);
 static int do_file_system_object_short(const char* path);
@@ -221,30 +222,28 @@ int do_file_system_object_short(const char* path)
  int columns;
  get_geometry(rows, columns);
 
- DIR* dirp = opendir(path);
- if (!dirp) {
- if (errno == ENOTDIR) {
+ CDirIterator di(path, !flag_show_dotfiles ? CDirIterator::SkipDots : CDirIterator::Flags::NoFlags);
+ if (di.has_error()) {
+ if (di.error() == ENOTDIR) {
  int nprinted;
  bool status = print_filesystem_object_short(path, path, &nprinted);
  printf("\n");
  if (status)
  return 0;
  return 2;
  }
- perror("opendir");
+ fprintf(stderr, "CDirIterator: %s\n", di.error_string());
  return 1;
  }
 
  Vector<String, 1024> names;
  int longest_name = 0;
- while (auto* de = readdir(dirp)) {
- if (de->d_name[0] == '.' && !flag_show_dotfiles)
- continue;
- names.append(de->d_name);
+ while (di.has_next()) {
+ String name = di.next_path();
+ names.append(name);
  if (names.last().length() > longest_name)
- longest_name = names.last().length();
+ longest_name = name.length();
  }
- closedir(dirp);
 
  int printed_on_row = 0;
  int nprinted;

Userland/pape.cpp

@@ -10,22 +10,22 @@
 #include <AK/Vector.h>
 #include <AK/FileSystemPath.h>
 #include <LibCore/CArgsParser.h>
+#include <LibCore/CDirIterator.h>
 #include <LibGUI/GDesktop.h>
 #include <LibGUI/GApplication.h>
 
 static int handle_show_all()
 {
- DIR* dirp = opendir("/res/wallpapers");
- if (!dirp) {
- perror("opendir");
+ CDirIterator di("/res/wallpapers", CDirIterator::SkipDots);
+ if (di.has_error()) {
+ fprintf(stderr, "CDirIterator: %s\n", di.error_string());
  return 1;
  }
- while (auto* de = readdir(dirp)) {
-  if (de->d_name[0] == '.')
-  continue;
- printf("%s\n", de->d_name);
+
+ while (di.has_next()) {
+ String name = di.next_path();
+ printf("%s\n", name.characters());
  }
- closedir(dirp);
  return 0;
 }
 

Userland/sysctl.cpp

@@ -8,6 +8,7 @@
 #include <AK/StringBuilder.h>
 #include <AK/Vector.h>
 #include <LibCore/CArgsParser.h>
+#include <LibCore/CDirIterator.h>
 
 static String read_var(const String& name)
 {
@@ -52,17 +53,16 @@ static void write_var(const String& name, const String& value)
 
 static int handle_show_all()
 {
- DIR* dirp = opendir("/proc/sys");
- if (!dirp) {
- perror("opendir");
+ CDirIterator di("/proc/sys", CDirIterator::SkipDots);
+ if (di.has_error()) {
+ fprintf(stderr, "CDirIterator: %s\n", di.error_string());
  return 1;
  }
- char pathbuf[PATH_MAX];
 
- while (auto* de = readdir(dirp)) {
-  if (de->d_name[0] == '.')
-  continue;
- sprintf(pathbuf, "/proc/sys/%s", de->d_name);
+ char pathbuf[PATH_MAX];
+ while (di.has_next()) {
+ String name = di.next_path();
+ sprintf(pathbuf, "/proc/sys/%s", name.characters());
  int fd = open(pathbuf, O_RDONLY);
  if (fd < 0) {
  perror("open");
@@ -76,11 +76,10 @@ static int handle_show_all()
  continue;
  }
  buffer[nread] = '\0';
- printf("%s = %s", de->d_name, buffer);
+ printf("%s = %s", name.characters(), buffer);
  if (nread && buffer[nread - 1] != '\n')
  printf("\n");
  }
- closedir(dirp);
  return 0;
 }