Add directory interface.

9 files changed, 565 insertions, 12 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 348cd36..df61f24 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -24,6 +24,7 @@ add_library(fud SHARED
     source/fud_utf8.cpp
     source/fud_utf8_iterator.cpp
     source/fud_sqlite.cpp
+    source/fud_directory.cpp
 )
 
 include(cmake/warnings.cmake)
@@ -96,6 +97,7 @@ set(FUD_HEADERS
     "include/fud_utf8.hpp"
     "include/fud_utf8_iterator.hpp"
     "include/fud_sqlite"
+    "include/fud_directory.hpp"
 )
 
 set_target_properties(fud PROPERTIES PUBLIC_HEADER "${FUD_HEADERS}")
diff --git a/include/fud_c_file.hpp b/include/fud_c_file.hpp
index f563a35..674130c 100644
--- a/include/fud_c_file.hpp
+++ b/include/fud_c_file.hpp
@@ -18,8 +18,8 @@
 #ifndef FUD_C_FILE_HPP
 #define FUD_C_FILE_HPP
 
-#include "fud_string.hpp"
 #include "fud_result.hpp"
+#include "fud_string.hpp"
 
 #include <cstdint>
 #include <cstdio>
@@ -88,7 +88,8 @@ enum class FileStatus
     Error,
 };
 
-static inline const char* FileStatusToString(FileStatus status) {
+static inline const char* FileStatusToString(FileStatus status)
+{
     switch (status) {
     case FileStatus::Success:
         return "Success";
@@ -114,6 +115,11 @@ struct [[nodiscard]] ReadResult {
     FileStatus status{FileStatus::Success};
 };
 
+struct [[nodiscard]] WriteResult {
+    size_t bytesWritten{0};
+    FileStatus status{FileStatus::Success};
+};
+
 class CBinaryFile {
   public:
     CBinaryFile(const String& filename, CFileMode mode);
@@ -146,6 +152,32 @@ class CBinaryFile {
         return read(&destination, sizeof(destination), length, offset);
     }
 
+    [[nodiscard]] WriteResult write(const void* source, size_t sourceSize, size_t length);
+
+    [[nodiscard]] WriteResult write(const void* source, size_t sourceSize, size_t length, size_t offset);
+
+    template <typename T>
+    [[nodiscard]] WriteResult write(const T& source)
+    {
+        return write(source, sizeof(source), sizeof(source));
+    }
+
+    template <typename T>
+    [[nodiscard]] WriteResult write(const T& source, size_t sourceSize, size_t length)
+    {
+        auto offsetResult = size();
+        if (offsetResult.isError()) {
+            return WriteResult{0, offsetResult.getError()};
+        }
+        return write(source, sourceSize, length, offsetResult.getOkay());
+    }
+
+    template <typename T>
+    [[nodiscard]] WriteResult write(const T& source, size_t sourceSize, size_t length, size_t offset)
+    {
+        return write(static_cast<const void*>(&source), sourceSize, length, offset);
+    }
+
   private:
     FileStatus reset() const;
 
@@ -158,5 +190,4 @@ class CBinaryFile {
 
 } // namespace fud
 
-
 #endif
diff --git a/include/fud_directory.hpp b/include/fud_directory.hpp
new file mode 100644
index 0000000..ac48b7b
--- /dev/null
+++ b/include/fud_directory.hpp
@@ -0,0 +1,87 @@
+/*
+ * libfud
+ * Copyright 2024 Dominick Allen
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef FUD_DIRECTORY_HPP
+#define FUD_DIRECTORY_HPP
+
+#include "fud_result.hpp"
+#include "fud_status.hpp"
+#include "fud_string.hpp"
+
+#include <cstdint>
+#include <cstdio>
+#include <dirent.h>
+#include <optional>
+#include <ctime>
+
+namespace fud {
+
+enum class DirectoryEntryType : uint8_t
+{
+    Block,
+    Character,
+    Directory,
+    NamedPipe,
+    SymbolicLink,
+    RegularFile,
+    UnixSocket,
+    Unknown
+};
+
+/** \brief Simplified Directory Entry */
+struct DirectoryEntry {
+    String name;
+    size_t size;
+    size_t links;
+    time_t modificationTime;
+    DirectoryEntryType entryType;
+};
+
+class Directory {
+  public:
+    explicit Directory(String name);
+    Directory(const Directory& rhs) = delete;
+    Directory(Directory&& rhs);
+    ~Directory();
+    Directory& operator=(const Directory& rhs) = delete;
+    Directory& operator=(Directory&& rhs);
+
+    constexpr FudStatus status() const
+    {
+        return m_status;
+    }
+
+    constexpr int errorCode() const
+    {
+        return m_errorCode;
+    }
+
+    Result<std::optional<DirectoryEntry>, FudStatus> getNextEntry();
+
+    FudStatus reset();
+
+  private:
+    String m_name{};
+    DIR* m_directory{nullptr};
+    FudStatus m_status{FudStatus::ObjectInvalid};
+    int m_errorCode{-1};
+    int m_dirFd{-1};
+};
+
+} // namespace fud
+
+#endif
diff --git a/include/fud_string.hpp b/include/fud_string.hpp
index 97b7036..9e423ef 100644
--- a/include/fud_string.hpp
+++ b/include/fud_string.hpp
@@ -113,9 +113,13 @@ class String {
 
     std::optional<utf8> pop();
 
-    [[nodiscard]] FudStatus catenate(StringView source);
+    [[nodiscard]] FudStatus append(StringView source);
 
-    [[nodiscard]] String append(const String& rhs) const;
+    [[nodiscard]] String catenate(const String& rhs) const;
+
+    [[nodiscard]] String catenate(const char* rhs) const;
+
+    [[nodiscard]] bool compare(const String& rhs) const;
 
     const utf8* begin() const;
 
diff --git a/source/fud_c_file.cpp b/source/fud_c_file.cpp
index a85fd00..cad4c9d 100644
--- a/source/fud_c_file.cpp
+++ b/source/fud_c_file.cpp
@@ -29,7 +29,7 @@ CBinaryFile::CBinaryFile(const String& filename, CFileMode mode)
 CBinaryFile::CBinaryFile(const String& filename, CFileMode mode, const String& extraFlags)
     : m_filename{filename},
       m_extraFlags{extraFlags},
-      m_mode{String(CBinaryFileModeFromFlags(mode)).append(extraFlags)},
+      m_mode{String(CBinaryFileModeFromFlags(mode)).catenate(extraFlags)},
       m_modeFlags{mode}
 {
 }
@@ -137,8 +137,8 @@ ReadResult CBinaryFile::read(void* destination, size_t destinationSize, size_t l
         return result;
     }
 
-    auto* destPtr = static_cast<char*>(destination);
-    result.bytesRead = fread(destPtr, 1, length, m_file);
+    auto* destBytes = static_cast<char*>(destination);
+    result.bytesRead = fread(destBytes, 1, length, m_file);
     static_cast<void>(reset());
     if (result.bytesRead != length) {
         result.status = FileStatus::PartialSuccess;
@@ -149,6 +149,65 @@ ReadResult CBinaryFile::read(void* destination, size_t destinationSize, size_t l
     return result;
 }
 
+WriteResult CBinaryFile::write(const void* source, size_t sourceSize, size_t length)
+{
+    auto offsetResult = size();
+    if (offsetResult.isError()) {
+        return WriteResult{0, offsetResult.getError()};
+    }
+
+    return write(source, sourceSize, length, offsetResult.getOkay());
+}
+
+WriteResult CBinaryFile::write(const void* source, size_t sourceSize, size_t length, size_t offset)
+{
+    WriteResult result{};
+    if (length == 0) {
+        return result;
+    }
+
+    if (source == nullptr) {
+        result.status = FileStatus::NullPointer;
+        return result;
+    }
+
+    if (offset > LONG_MAX || SIZE_MAX - offset < length || sourceSize < length) {
+        result.status = FileStatus::InvalidArgument;
+        return result;
+    }
+
+    auto fileSizeResult = size();
+    if (fileSizeResult.isError()) {
+        result.status = fileSizeResult.getError();
+        return result;
+    }
+
+    // TODO: proper way of handling this
+    auto fileSize = fileSizeResult.getOkay();
+    int seekResult;
+    if (offset > fileSize) {
+        seekResult = fseek(m_file, 0, SEEK_END);
+    } else {
+        seekResult = fseek(m_file, static_cast<long>(offset), SEEK_SET);
+    }
+
+    if (seekResult != 0) {
+        result.status = FileStatus::Error;
+        return result;
+    }
+
+    auto* sourceBytes = static_cast<const char*>(source);
+    result.bytesWritten = fwrite(sourceBytes, 1, length, m_file);
+    static_cast<void>(reset());
+    if (result.bytesWritten != length) {
+        result.status = FileStatus::PartialSuccess;
+    } else {
+        result.status = FileStatus::Success;
+    }
+
+    return result;
+}
+
 FileStatus CBinaryFile::reset() const {
     if (!isOpen()) {
         return FileStatus::InvalidState;
diff --git a/source/fud_directory.cpp b/source/fud_directory.cpp
new file mode 100644
index 0000000..39f2e10
--- /dev/null
+++ b/source/fud_directory.cpp
@@ -0,0 +1,192 @@
+/*
+ * libfud
+ * Copyright 2024 Dominick Allen
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "fud_directory.hpp"
+
+#include <cerrno>
+#include <fcntl.h>
+#include <sys/stat.h>
+
+namespace fud {
+
+Directory::Directory(String name) : m_name{name}
+{
+    if (!m_name.valid()) {
+        return;
+    }
+
+    if (!m_name.utf8Valid()) {
+        m_status = FudStatus::Utf8Invalid;
+        return;
+    }
+
+    m_directory = opendir(m_name.c_str());
+    if (m_directory == nullptr) {
+        m_status = FudStatus::Failure;
+        m_errorCode = errno;
+        return;
+    }
+
+    m_dirFd = dirfd(m_directory);
+    if (m_dirFd == -1) {
+        m_status = FudStatus::Failure;
+        m_errorCode = errno;
+        closedir(m_directory);
+        m_directory = nullptr;
+        return;
+    }
+
+    m_errorCode = 0;
+    m_status = FudStatus::Success;
+}
+
+Directory::Directory(Directory&& rhs) :
+    m_name{std::move(rhs.m_name)}, m_directory{rhs.m_directory}, m_dirFd{rhs.m_dirFd}
+{
+    rhs.m_directory = nullptr;
+    rhs.m_dirFd = -1;
+}
+
+Directory& Directory::operator=(Directory&& rhs)
+{
+    m_name = std::move(rhs.m_name);
+    m_directory = rhs.m_directory;
+    m_dirFd = rhs.m_dirFd;
+
+    rhs.m_directory = nullptr;
+    rhs.m_dirFd = -1;
+
+    return *this;
+}
+
+Directory::~Directory()
+{
+    if (m_directory != nullptr) {
+        closedir(m_directory);
+        m_directory = nullptr;
+    }
+}
+
+Result<std::optional<DirectoryEntry>, FudStatus> Directory::getNextEntry()
+{
+    using RetType = Result<std::optional<DirectoryEntry>, FudStatus>;
+
+    if (m_directory == nullptr || m_dirFd == -1) {
+        m_status = FudStatus::ObjectInvalid;
+        return RetType::error(m_status);
+    }
+
+    errno = 0;
+    auto* dirEntry = readdir(m_directory);
+    if (dirEntry == nullptr) {
+        if (errno != 0) {
+            m_errorCode = errno;
+            m_status = FudStatus::Failure;
+            return RetType::error(m_status);
+        } else {
+            return RetType::okay(std::nullopt);
+        }
+    }
+
+    const char* entryName = dirEntry->d_name;
+    if (entryName == nullptr) {
+        m_errorCode = -1;
+        m_status = FudStatus::NullPointer;
+        return RetType::error(m_status);
+    }
+
+    m_errorCode = 0;
+
+    using Stat = struct stat;
+    Stat statBuffer{};
+    auto flags = 0;
+    auto status = fstatat(m_dirFd, entryName, &statBuffer, flags);
+    if (status == -1) {
+        m_errorCode = errno;
+        m_status = FudStatus::Failure;
+        return RetType::error(m_status);
+    }
+
+    DirectoryEntryType entryType;
+    switch (statBuffer.st_mode & S_IFMT) {
+    case S_IFBLK:
+        entryType = DirectoryEntryType::Block;
+        break;
+    case S_IFCHR:
+        entryType = DirectoryEntryType::Character;
+        break;
+    case S_IFDIR:
+        entryType = DirectoryEntryType::Directory;
+        break;
+    case S_IFIFO:
+        entryType = DirectoryEntryType::NamedPipe;
+        break;
+    case S_IFLNK:
+        entryType = DirectoryEntryType::SymbolicLink;
+        break;
+    case S_IFREG:
+        entryType = DirectoryEntryType::RegularFile;
+        break;
+    case S_IFSOCK:
+        entryType = DirectoryEntryType::UnixSocket;
+        break;
+    default:
+        entryType = DirectoryEntryType::Unknown;
+        break;
+    }
+
+    static_assert(std::is_same_v<decltype(statBuffer.st_size), long>);
+    static_assert(sizeof(decltype(statBuffer.st_size)) <= sizeof(size_t));
+
+    size_t size{0};
+    if (statBuffer.st_size < 0) {
+        size = SIZE_MAX;
+    } else {
+        size = static_cast<size_t>(statBuffer.st_size);
+    }
+
+    static_assert(std::is_same_v<decltype(statBuffer.st_nlink), unsigned long>);
+    static_assert(sizeof(decltype(statBuffer.st_nlink)) <= sizeof(size_t));
+
+    DirectoryEntry entry{
+        String{dirEntry->d_name},
+        size,
+        static_cast<size_t>(statBuffer.st_nlink),
+        statBuffer.st_mtime,
+        entryType};
+
+    if (!entry.name.valid()) {
+        m_status = FudStatus::StringInvalid;
+        return RetType::error(m_status);
+    }
+
+    m_status = FudStatus::Success;
+    return RetType::okay(std::move(entry));
+}
+
+FudStatus Directory::reset()
+{
+    if (m_directory != nullptr) {
+        rewinddir(m_directory);
+    } else {
+        m_status = FudStatus::ObjectInvalid;
+        return m_status;
+    }
+    return FudStatus::NotImplemented;
+}
+
+} // namespace fud
diff --git a/source/fud_string.cpp b/source/fud_string.cpp
index 74742e1..52d6b8f 100644
--- a/source/fud_string.cpp
+++ b/source/fud_string.cpp
@@ -236,7 +236,7 @@ FudStatus String::pushBack(const FudUtf8& letter)
     return FudStatus::Success;
 }
 
-FudStatus String::catenate(StringView source)
+FudStatus String::append(StringView source)
 {
     if (!valid()) {
         return FudStatus::StringInvalid;
@@ -262,13 +262,19 @@ FudStatus String::catenate(StringView source)
     return status;
 }
 
-String String::append(const String& rhs) const
+String String::catenate(const char* rhs) const
+{
+    String rhsString{rhs};
+    return catenate(rhsString);
+}
+
+String String::catenate(const String& rhs) const
 {
     String output{};
     output.m_length = 1;
     output.m_capacity = 0;
 
-    if (!valid()) {
+    if (!valid() || !rhs.valid()) {
         return output;
     }
 
@@ -279,7 +285,9 @@ String String::append(const String& rhs) const
     }
 
     auto* destPtr = output.data();
-    auto status = copyMem(destPtr, m_capacity, rhs.data(), rhs.length());
+    auto status = copyMem(destPtr, m_capacity, data(), length());
+    fudAssert(status == FudStatus::Success);
+    status = copyMem(destPtr + length(), m_capacity, rhs.data(), rhs.length());
     fudAssert(status == FudStatus::Success);
     static_cast<void>(status);
     fudAssert(output.nullTerminate() == FudStatus::Success);
@@ -287,6 +295,28 @@ String String::append(const String& rhs) const
     return output;
 }
 
+bool String::compare(const String& rhs) const {
+    if (!valid() || !rhs.valid()) {
+        return false;
+    }
+
+    if (length() != rhs.length()) {
+        return false;
+    }
+
+    if (isLarge() && data() == rhs.data())
+    {
+        return true;
+    }
+
+    auto diffResult = compareMem(data(), length(), rhs.data(), rhs.length());
+    if (diffResult.isError()) {
+        return false;
+    }
+
+    return diffResult.getOkay() == 0;
+}
+
 const utf8* String::begin() const
 {
     return data();
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 73968fe..9061d55 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -54,6 +54,7 @@ endfunction()
 fud_add_test(test_result SOURCES test_result.cpp)
 fud_add_test(test_string SOURCES test_string.cpp)
 fud_add_test(test_sqlite SOURCES test_sqlite.cpp)
+fud_add_test(test_directory SOURCES test_directory.cpp)
 # fud_add_test(test_deserialize_number SOURCES test_deserialize_number.cpp)
 # fud_add_test(test_ext_algorithm SOURCES test_algorithm.cpp)
 # fud_add_test(test_ext_array SOURCES
diff --git a/test/test_directory.cpp b/test/test_directory.cpp
new file mode 100644
index 0000000..9cec80d
--- /dev/null
+++ b/test/test_directory.cpp
@@ -0,0 +1,147 @@
+/*
+ * libfud
+ * Copyright 2024 Dominick Allen
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "fud_array.hpp"
+#include "fud_c_file.hpp"
+#include "fud_directory.hpp"
+#include "fud_memory.hpp"
+#include "fud_string.hpp"
+#include "test_common.hpp"
+
+#include "gtest/gtest.h"
+#include <algorithm>
+#include <cerrno>
+#include <fcntl.h>
+#include <ftw.h>
+#include <ranges>
+
+namespace fud {
+
+int unlink_cb(const char* fpath, const struct stat* sb, int typeflag, struct FTW* ftwbuf)
+{
+    int retValue = remove(fpath);
+
+    EXPECT_EQ(retValue, 0);
+    if (retValue) {
+        perror(fpath);
+    }
+
+    return retValue;
+}
+
+FudStatus removeRecursive(const String& path)
+{
+    if (!path.utf8Valid()) {
+        return FudStatus::Utf8Invalid;
+    }
+    if (path.length() < 5) {
+        return FudStatus::InvalidInput;
+    }
+    const String prefix{"/tmp/"};
+    auto diffResult = compareMem(path.data(), path.length(), prefix.data(), prefix.length());
+    if (diffResult.isError()) {
+        return FudStatus::InvalidInput;
+    }
+    auto diff = diffResult.getOkay();
+    if (diff != 0) {
+        return FudStatus::InvalidInput;
+    }
+    constexpr int maxOpenFd = 64;
+    auto status = nftw(path.c_str(), unlink_cb, maxOpenFd, FTW_DEPTH | FTW_PHYS);
+    if (status == 0) {
+        return FudStatus::Success;
+    }
+
+    if (errno == ENOENT) {
+        return FudStatus::Success;
+    }
+
+    return FudStatus::Failure;
+}
+
+TEST(FudDirectory, Basic)
+{
+    const String testDirName{"/tmp/fud_directory_test"};
+    ASSERT_TRUE(testDirName.utf8Valid());
+    constexpr mode_t pathMode = 0777;
+    const Array<String, 2> files{
+        String{"file1"},
+        String{"file2"},
+    };
+    ASSERT_TRUE(files[0].utf8Valid());
+    ASSERT_TRUE(files[1].utf8Valid());
+
+    ASSERT_EQ(removeRecursive(testDirName), FudStatus::Success);
+
+    auto mkdirResult = mkdir(testDirName.c_str(), pathMode);
+    EXPECT_EQ(mkdirResult, 0);
+    if (mkdirResult != 0) {
+        ASSERT_EQ(removeRecursive(testDirName), FudStatus::Success);
+        return;
+    }
+
+    const String testDirNamePrefix = testDirName.catenate("/");
+    ASSERT_TRUE(testDirNamePrefix.utf8Valid());
+    for (const auto& fnameBase : files) {
+        const auto fname = testDirNamePrefix.catenate(fnameBase);
+        ASSERT_TRUE(fname.utf8Valid());
+        CBinaryFile file{fname, CFileMode::ReadWriteTruncate};
+        ASSERT_EQ(file.open(), FileStatus::Success);
+        Array<utf8, 5> data{"test"};
+        WriteResult expected{data.size(), FileStatus::Success};
+        auto writeResult = file.write(data);
+        ASSERT_EQ(writeResult.bytesWritten, expected.bytesWritten);
+        ASSERT_EQ(writeResult.status, expected.status);
+    }
+
+    Directory directory{testDirName};
+    ASSERT_EQ(directory.status(), FudStatus::Success);
+    ASSERT_EQ(directory.errorCode(), 0);
+
+    const Array<DirectoryEntry, 4> expectedFiles{
+        DirectoryEntry{String{"."}, 0, 2, 0, DirectoryEntryType::Directory},
+        DirectoryEntry{String{".."}, 0, 1, 0, DirectoryEntryType::Directory},
+        DirectoryEntry{files[0], files[0].size(), 1, 0, DirectoryEntryType::RegularFile},
+        DirectoryEntry{files[1], files[1].size(), 1, 0, DirectoryEntryType::RegularFile},
+    };
+    ASSERT_TRUE(expectedFiles[0].name.compare(expectedFiles[0].name));
+
+    for (auto idx = 0; idx < expectedFiles.size(); ++idx) {
+        auto dirEntryResult = directory.getNextEntry();
+        EXPECT_TRUE(dirEntryResult.isOkay());
+        const auto dirEntryOpt = dirEntryResult.getOkay();
+        if (dirEntryOpt == std::nullopt) {
+            break;
+        }
+        const auto dirEntry = *dirEntryOpt;
+        const auto expected = std::find_if(
+            expectedFiles.begin(),
+            expectedFiles.end(),
+            [&dirEntry](const DirectoryEntry& entry) { return entry.name.compare(dirEntry.name) && entry.entryType == dirEntry.entryType; });
+        EXPECT_NE(expected, nullptr);
+        EXPECT_NE(expected, expectedFiles.end());
+        printf("%s %u\n", dirEntry.name.c_str(), static_cast<uint8_t>(dirEntry.entryType));
+    }
+
+    auto finalDirEntryResult = directory.getNextEntry();
+    EXPECT_TRUE(finalDirEntryResult.isOkay());
+    EXPECT_EQ(finalDirEntryResult.getOkay(), std::nullopt);
+
+    // ASSERT_EQ(removeRecursive(testDirName), FudStatus::Success);
+}
+
+} // namespace fud