libos+init: Add a standard API for config file access

Wasn't causing problems earlier, but when trying to rebuild the toolchain, it failed because of this.

libluna/CMakeLists.txt

@@ -19,6 +19,7 @@ set(FREESTANDING_SOURCES
     src/SHA.cpp
     src/Stack.cpp
     src/String.cpp
+    src/RefString.cpp
     src/StringBuilder.cpp
     src/StringView.cpp
     src/Utf8.cpp
@@ -51,6 +52,9 @@ add_library(luna ${SOURCES})
 target_compile_options(luna PRIVATE ${COMMON_FLAGS})
 target_include_directories(luna PUBLIC include/)
 target_include_directories(luna PUBLIC ${LUNA_BASE}/usr/include)
+if(DEFINED LIBC_BOOTSTRAP)
+target_compile_definitions(luna PUBLIC LIBC_BOOTSTRAP)
+endif()
 
 if("${LUNA_ARCH}" MATCHES "x86_64")
 target_compile_options(luna-freestanding PRIVATE -mno-red-zone)

libluna/include/luna/RefString.h

@@ -0,0 +1,120 @@
+/**
+ * @file RefString.h
+ * @author apio (cloudapio.eu)
+ * @brief Reference-counted, trivially-copyable, immutable string type.
+ *
+ * @copyright Copyright (c) 2024, the Luna authors.
+ *
+ */
+
+#pragma once
+#include <luna/Hash.h>
+#include <luna/Result.h>
+#include <luna/SharedPtr.h>
+#include <luna/String.h>
+#include <luna/StringView.h>
+#include <stdarg.h>
+
+class RefString
+{
+    typedef const char* ConstIterator;
+
+  public:
+    /* Constructs an empty String. */
+    RefString();
+
+    RefString(RefString&&);
+
+    RefString(const RefString&);
+
+    RefString& operator=(const RefString&);
+
+    bool operator==(const RefString& other) const
+    {
+        return !compare(this, &other);
+    }
+
+    ~RefString() = default;
+
+    /* Creates a copy of a specific segment of this String and returns it. */
+    Result<RefString> substring(usize begin, usize size) const;
+
+    /* Splits a String with a delimiter. */
+    Result<Vector<RefString>> split(StringView delim) const
+    {
+        return view().ref_split(delim);
+    }
+
+    /* Splits a String into two parts with a delimiter. */
+    Result<Vector<RefString>> split_once(char delim) const
+    {
+        return view().ref_split_once(delim);
+    }
+
+    /* Creates a single String consisting of a list of strings separated by a delimiter. */
+    static Result<RefString> join(const Vector<RefString>& vec, StringView delim);
+
+    /* Creates a single String consisting of a list of strings separated by a delimiter. */
+    static Result<RefString> join(const Vector<StringView>& vec, StringView delim);
+
+    static Result<RefString> format(StringView fmt, ...);
+    static Result<RefString> vformat(StringView fmt, va_list ap);
+
+    static Result<RefString> from_cstring(const char* str);
+    static Result<RefString> from_string_view(StringView str);
+    static Result<RefString> from_string(const String& str);
+
+    static int compare(const RefString* a, const RefString* b);
+
+    const char* chars() const;
+
+    usize length() const
+    {
+        return m_string_data ? m_string_data->length : 0;
+    }
+
+    bool is_empty() const
+    {
+        return length() == 0;
+    }
+
+    StringView view() const
+    {
+        return { chars(), length() };
+    }
+
+    const char& operator[](usize) const;
+
+    ConstIterator begin() const
+    {
+        return chars();
+    }
+
+    ConstIterator end() const
+    {
+        return begin() + length();
+    }
+
+  private:
+    struct RefStringData : public Shareable
+    {
+        char* string { nullptr };
+        usize length { 0 };
+
+        RefStringData(char* s, usize l) : Shareable(), string(s), length(l)
+        {
+        }
+
+        ~RefStringData()
+        {
+            if (string) free_impl(string);
+        }
+    };
+
+    SharedPtr<RefStringData> m_string_data { nullptr };
+
+    static Result<RefString> adopt(char* c_str);
+    static Result<RefString> adopt(char* c_str, usize length);
+};
+
+template <> u64 hash(const RefString& value, u64 salt);

libluna/include/luna/StringView.h

@@ -4,6 +4,7 @@
 #include <luna/Vector.h>
 
 class String;
+class RefString;
 
 class StringView
 {
@@ -43,6 +44,8 @@ class StringView
 
     Result<Vector<String>> split(StringView delim) const;
     Result<Vector<String>> split_once(char delim) const;
+    Result<Vector<RefString>> ref_split(StringView delim) const;
+    Result<Vector<RefString>> ref_split_once(char delim) const;
     Result<Vector<StringView>> split_view(char delim) const;
 
     bool contains(char v) const;

libluna/src/Heap.cpp

@@ -420,35 +420,39 @@ void dump_heap_usage()
     dbgln("-- Heap memory in use: %zu bytes", alloc_used);
 }
 
-// Otherwise, this is defined in libstdc++.
+#if defined(USE_FREESTANDING) || defined(LIBC_BOOTSTRAP)
-#ifdef USE_FREESTANDING
+#define WEAK
-void* operator new(usize size, const std::nothrow_t&) noexcept
+#else
-{
+#define WEAK __attribute__((weak))
-    return malloc_impl(size, false, false).value_or(nullptr);
-}
-
-void* operator new[](usize size, const std::nothrow_t&) noexcept
-{
-    return malloc_impl(size, false, false).value_or(nullptr);
-}
-
-void operator delete(void* p) noexcept
-{
-    free_impl(p);
-}
-
-void operator delete[](void* p) noexcept
-{
-    free_impl(p);
-}
-
-void operator delete(void* p, usize) noexcept
-{
-    free_impl(p);
-}
-
-void operator delete[](void* p, usize) noexcept
-{
-    free_impl(p);
-}
 #endif
+
+// If libstdc++ is linked, it should override these definitions.
+void* WEAK operator new(usize size, const std::nothrow_t&) noexcept
+{
+    return malloc_impl(size, false, false).value_or(nullptr);
+}
+
+void* WEAK operator new[](usize size, const std::nothrow_t&) noexcept
+{
+    return malloc_impl(size, false, false).value_or(nullptr);
+}
+
+void WEAK operator delete(void* p) noexcept
+{
+    free_impl(p);
+}
+
+void WEAK operator delete[](void* p) noexcept
+{
+    free_impl(p);
+}
+
+void WEAK operator delete(void* p, usize) noexcept
+{
+    free_impl(p);
+}
+
+void WEAK operator delete[](void* p, usize) noexcept
+{
+    free_impl(p);
+}

libluna/src/RefString.cpp

@@ -0,0 +1,122 @@
+/**
+ * @file RefString.cpp
+ * @author apio (cloudapio.eu)
+ * @brief Reference-counted, trivially-copyable, immutable string type.
+ *
+ * @copyright Copyright (c) 2024, the Luna authors.
+ *
+ */
+
+#include <luna/Format.h>
+#include <luna/RefString.h>
+
+static const char empty_string[] = { 0 };
+
+RefString::RefString()
+{
+}
+
+RefString::RefString(RefString&& other) : m_string_data(move(other.m_string_data))
+{
+}
+
+RefString::RefString(const RefString& other) : m_string_data(other.m_string_data)
+{
+}
+
+const char* RefString::chars() const
+{
+    if (m_string_data) return m_string_data->string;
+    return empty_string;
+}
+
+RefString& RefString::operator=(const RefString& other)
+{
+    if (&other == this) return *this;
+    m_string_data = other.m_string_data;
+    return *this;
+}
+
+Result<RefString> RefString::substring(usize begin, usize size) const
+{
+    if (begin + size >= size) return err(EINVAL);
+    char* const dup = strndup(chars() + begin, size);
+    if (!dup) return err(ENOMEM);
+    return adopt(dup, size);
+}
+
+const char& RefString::operator[](usize index) const
+{
+    expect(index < length(), "index out of range");
+    return chars()[index];
+}
+
+Result<RefString> RefString::format(StringView fmt, ...)
+{
+    va_list ap;
+    va_start(ap, fmt);
+
+    auto rc = vformat(fmt, ap);
+
+    va_end(ap);
+
+    return rc;
+}
+
+Result<RefString> RefString::vformat(StringView fmt, va_list ap)
+{
+    Vector<char> buf;
+
+    TRY(cstyle_format(
+        fmt.chars(), [](char c, void* data) -> Result<void> { return ((Vector<char>*)data)->try_append(c); }, &buf,
+        ap));
+
+    TRY(buf.try_append(0));
+
+    return adopt(buf.release_data());
+}
+
+Result<RefString> RefString::from_cstring(const char* str)
+{
+    return from_string_view(StringView { str });
+}
+
+Result<RefString> RefString::from_string(const String& str)
+{
+    return from_string_view(str.view());
+}
+
+Result<RefString> RefString::from_string_view(StringView str)
+{
+    char* const dup = strndup(str.chars(), str.length());
+    if (!dup) return err(ENOMEM);
+    return adopt(dup, str.length());
+}
+
+int RefString::compare(const RefString* a, const RefString* b)
+{
+    return strcmp(a->chars(), b->chars());
+}
+
+Result<RefString> RefString::adopt(char* c_str)
+{
+    return adopt(c_str, strlen(c_str));
+}
+
+Result<RefString> RefString::adopt(char* c_str, usize length)
+{
+    auto guard = make_scope_guard([&] { free_impl(c_str); });
+
+    auto data = TRY(make_shared<RefStringData>(c_str, length));
+
+    guard.deactivate();
+
+    RefString string;
+    string.m_string_data = data;
+    return string;
+}
+
+template <> u64 hash(const RefString& value, u64 salt)
+{
+    return hash_memory(value.chars(), value.length(), salt);
+}

libluna/src/StringView.cpp

@@ -1,5 +1,6 @@
 #include <luna/CString.h>
 #include <luna/NumberParsing.h>
+#include <luna/RefString.h>
 #include <luna/ScopeGuard.h>
 #include <luna/String.h>
 #include <luna/StringView.h>
@@ -86,6 +87,32 @@ Result<Vector<String>> StringView::split(StringView delim) const
     return result;
 }
 
+Result<Vector<RefString>> StringView::ref_split(StringView delim) const
+{
+    Vector<RefString> result;
+    RefString str;
+
+    char* copy = strndup(m_string, m_length);
+    auto guard = make_scope_guard([copy] { free_impl(copy); });
+
+    char* segment = strtok(copy, delim.chars());
+    if (!segment) return result;
+
+    str = TRY(RefString::from_cstring(segment));
+    TRY(result.try_append(move(str)));
+
+    while (true)
+    {
+        segment = strtok(nullptr, delim.chars());
+        if (!segment) return result;
+
+        str = TRY(RefString::from_cstring(segment));
+        TRY(result.try_append(move(str)));
+    }
+
+    return result;
+}
+
 Result<Vector<String>> StringView::split_once(char delim) const
 {
     Vector<String> result;
@@ -112,6 +139,32 @@ Result<Vector<String>> StringView::split_once(char delim) const
     return result;
 }
 
+Result<Vector<RefString>> StringView::ref_split_once(char delim) const
+{
+    Vector<RefString> result;
+
+    char* copy = strndup(m_string, m_length);
+    auto guard = make_scope_guard([copy] { free_impl(copy); });
+
+    char* middle = strchr(copy, delim);
+    if (!middle)
+    {
+        auto str = TRY(RefString::from_cstring(copy));
+        TRY(result.try_append(move(str)));
+        return result;
+    }
+
+    *middle = '\0';
+
+    auto begin = TRY(RefString::from_cstring(copy));
+    auto end = TRY(RefString::from_cstring(middle + 1));
+
+    TRY(result.try_append(move(begin)));
+    TRY(result.try_append(move(end)));
+
+    return result;
+}
+
 Result<Vector<StringView>> StringView::split_view(char delim) const
 {
     Vector<StringView> result;

libos/CMakeLists.txt

@@ -20,6 +20,7 @@ set(SOURCES
     src/IPC.cpp
     src/SharedMemory.cpp
     src/Timer.cpp
+    src/Config.cpp
 )
 
 add_library(os ${SOURCES})

libos/include/os/Config.h

@@ -0,0 +1,43 @@
+/**
+ * @file Config.h
+ * @author apio (cloudapio.eu)
+ * @brief Configuration file parsing.
+ *
+ * @copyright Copyright (c) 2024, the Luna authors.
+ *
+ */
+
+#pragma once
+#include <luna/HashMap.h>
+#include <luna/RefString.h>
+#include <os/File.h>
+#include <os/Path.h>
+
+namespace os
+{
+    class ConfigFile
+    {
+      public:
+        static Result<OwnedPtr<ConfigFile>> open(os::Path path);
+
+        Option<StringView> read_string(StringView key);
+        StringView read_string_or(StringView key, StringView default_value);
+
+        Option<i64> read_number(StringView key);
+        i64 read_number_or(StringView key, i64 default_value);
+
+        Option<bool> read_boolean(StringView key);
+        bool read_boolean_or(StringView key, bool default_value);
+
+        Result<void> write_string(StringView key, StringView value);
+        Result<void> write_number(StringView key, int value);
+        Result<void> write_boolean(StringView key, bool value);
+
+        Result<void> sync();
+
+      private:
+        os::Path m_path { "" };
+
+        HashMap<RefString, RefString> m_data;
+    };
+}

libos/src/Config.cpp

@@ -0,0 +1,139 @@
+/**
+ * @file Config.cpp
+ * @author apio (cloudapio.eu)
+ * @brief Configuration file parsing.
+ *
+ * @copyright Copyright (c) 2024, the Luna authors.
+ *
+ */
+
+#include <os/Config.h>
+#include <stdlib.h>
+
+namespace os
+{
+    Result<OwnedPtr<ConfigFile>> ConfigFile::open(os::Path path)
+    {
+        auto config = TRY(make_owned<ConfigFile>());
+
+        config->m_path = path;
+
+        auto file = TRY(os::File::open(path, os::File::ReadOnly));
+
+        while (true)
+        {
+            auto line = TRY(file->read_line());
+            if (line.is_empty()) break;
+
+            line.trim("\n");
+            if (line.is_empty()) continue;
+
+            auto parts = TRY(line.split_once('='));
+            if (parts.size() < 2 || parts[0].is_empty() || parts[1].is_empty()) return err(EINVAL);
+
+            auto key = TRY(RefString::from_string(parts[0]));
+            auto value = TRY(RefString::from_string(parts[1]));
+
+            config->m_data.try_set(key, value);
+        }
+
+        return config;
+    }
+
+    Option<StringView> ConfigFile::read_string(StringView key)
+    {
+        auto string = RefString::from_string_view(key).release_value();
+        auto* value = m_data.try_get_ref(string);
+
+        if (!value) return {};
+
+        return value->view();
+    }
+
+    StringView ConfigFile::read_string_or(StringView key, StringView default_value)
+    {
+        return read_string(key).value_or(default_value);
+    }
+
+    Option<i64> ConfigFile::read_number(StringView key)
+    {
+        auto maybe_string = read_string(key);
+
+        if (!maybe_string.has_value()) return {};
+
+        auto string = maybe_string.value();
+
+        char* endptr;
+
+        i64 result = strtol(string.chars(), &endptr, 10);
+
+        if (string.chars() == endptr) return {};
+
+        return result;
+    }
+
+    i64 ConfigFile::read_number_or(StringView key, i64 default_value)
+    {
+        return read_number(key).value_or(default_value);
+    }
+
+    Option<bool> ConfigFile::read_boolean(StringView key)
+    {
+        auto maybe_string = read_string(key);
+
+        if (!maybe_string.has_value()) return {};
+
+        auto string = maybe_string.value();
+
+        if (string == "true" || string.to_uint().value_or(0) == 1) return true;
+        if (string == "false" || string.to_uint().value_or(1) == 0) return false;
+
+        return {};
+    }
+
+    bool ConfigFile::read_boolean_or(StringView key, bool default_value)
+    {
+        return read_boolean(key).value_or(default_value);
+    }
+
+    Result<void> ConfigFile::write_string(StringView key, StringView value)
+    {
+        auto key_string = TRY(RefString::from_string_view(key));
+        auto value_string = TRY(RefString::from_string_view(value));
+
+        auto worked = TRY(m_data.try_set(key_string, value_string));
+        if (!worked)
+        {
+            m_data.try_remove(key_string);
+            check(TRY(m_data.try_set(key_string, value_string)));
+        }
+
+        return {};
+    }
+
+    Result<void> ConfigFile::write_number(StringView key, int value)
+    {
+        auto value_string = TRY(String::format("%d"_sv, value));
+
+        return write_string(key, value_string.view());
+    }
+
+    Result<void> ConfigFile::write_boolean(StringView key, bool value)
+    {
+        StringView value_string = value ? "true" : "false";
+
+        return write_string(key, value_string);
+    }
+
+    Result<void> ConfigFile::sync()
+    {
+        auto file = TRY(os::File::open(m_path, os::File::WriteOnly));
+
+        for (auto& pair : m_data)
+        {
+            file->write_formatted("%s=%s\n", pair.key.chars(), pair.value.release_value().chars());
+        }
+
+        return {};
+    }
+}

system/init.cpp

@@ -6,6 +6,7 @@
 #include <luna/Utf8.h>
 #include <luna/Vector.h>
 #include <os/ArgumentParser.h>
+#include <os/Config.h>
 #include <os/Directory.h>
 #include <os/File.h>
 #include <os/IPC.h>
@@ -191,129 +192,49 @@ static Result<void> load_service(const os::Path& path)
 {
     do_log("[init] reading service file: %s\n", path.name().chars());
 
-    auto file = TRY(os::File::open(path, os::File::ReadOnly));
+    auto file = TRY(os::ConfigFile::open(path));
 
     Service service;
 
-    while (true)
+    auto name = file->read_string("Name");
-    {
+    if (!name.has_value())
-        auto line = TRY(file->read_line());
-        if (line.is_empty()) break;
-
-        line.trim("\n");
-        if (line.is_empty()) continue;
-
-        auto parts = TRY(line.split_once('='));
-        if (parts.size() < 2 || parts[0].is_empty() || parts[1].is_empty())
-        {
-            do_log("[init] file contains invalid line, aborting: '%s'\n", line.chars());
-            return {};
-        }
-
-        if (parts[0].view() == "Name")
-        {
-            service.name = move(parts[1]);
-            continue;
-        }
-
-        if (parts[0].view() == "Description")
-        {
-            // We let users specify this in the config file, but init doesn't actually use it.
-            continue;
-        }
-
-        if (parts[0].view() == "Command")
-        {
-            service.command = move(parts[1]);
-            continue;
-        }
-
-        if (parts[0].view() == "Restart")
-        {
-            if (parts[1].view() == "true" || parts[1].view().to_uint().value_or(0) == 1)
-            {
-                service.restart = true;
-                continue;
-            }
-            service.restart = false;
-            continue;
-        }
-
-        if (parts[0].view() == "Environment")
-        {
-            service.environment = move(parts[1]);
-            continue;
-        }
-
-        if (parts[0].view() == "StandardOutput")
-        {
-            service.standard_output = move(parts[1]);
-            continue;
-        }
-
-        if (parts[0].view() == "StandardError")
-        {
-            service.standard_error = move(parts[1]);
-            continue;
-        }
-
-        if (parts[0].view() == "StandardInput")
-        {
-            service.standard_input = move(parts[1]);
-            continue;
-        }
-
-        if (parts[0].view() == "WorkingDirectory")
-        {
-            service.working_directory = move(parts[1]);
-            continue;
-        }
-
-        if (g_is_system && parts[0].view() == "User")
-        {
-            auto* pw = getpwnam(parts[1].chars());
-            if (!pw) continue;
-            service.user = pw->pw_uid;
-            service.group = pw->pw_gid;
-            continue;
-        }
-
-        if (parts[0].view() == "Wait")
-        {
-            if (parts[1].view() == "true" || parts[1].view().to_uint().value_or(0) == 1)
-            {
-                service.wait = true;
-                continue;
-            }
-            service.wait = false;
-            continue;
-        }
-
-        if (parts[0].view() == "WaitUntilReady")
-        {
-            if (parts[1].view() == "true" || parts[1].view().to_uint().value_or(0) == 1)
-            {
-                service.wait_notify = true;
-                continue;
-            }
-            service.wait_notify = false;
-            continue;
-        }
-
-        do_log("[init] skipping unknown entry name %s\n", parts[0].chars());
-    }
-
-    if (service.name.is_empty())
     {
         do_log("[init] service file is missing 'Name' entry, aborting!\n");
         return {};
     }
+    service.name = TRY(String::from_string_view(name.value()));
 
-    if (service.command.is_empty())
+    auto command = file->read_string("Command");
+    if (!command.has_value())
     {
         do_log("[init] service file is missing 'Command' entry, aborting!\n");
         return {};
     }
+    service.command = TRY(String::from_string_view(command.value()));
+
+    service.restart = file->read_boolean_or("Restart", false);
+    service.environment = TRY(String::from_string_view(file->read_string_or("Environment", {})));
+    service.standard_output = TRY(String::from_string_view(file->read_string_or("StandardOutput", {})));
+    service.standard_error = TRY(String::from_string_view(file->read_string_or("StandardError", {})));
+    service.standard_input = TRY(String::from_string_view(file->read_string_or("StandardInput", {})));
+    service.working_directory = TRY(String::from_string_view(file->read_string_or("WorkingDirectory", {})));
+
+    if (g_is_system)
+    {
+        auto user = file->read_string("User");
+        if (user.has_value())
+        {
+            auto* pw = getpwnam(user.value().chars());
+            if (pw)
+            {
+                service.user = pw->pw_uid;
+                service.group = pw->pw_gid;
+            }
+        }
+    }
+
+    service.wait = file->read_boolean_or("Wait", false);
+    service.wait_notify = file->read_boolean_or("WaitUntilReady", false);
 
     do_log("[init] loaded service %s into memory\n", service.name.chars());
 

tools/setup-gcc.sh

@@ -64,7 +64,7 @@ make install-gcc
 make install-target-libgcc
 
 mkdir -p $LUNA_BUILD_DIR
-cmake -S $LUNA_ROOT -B $LUNA_BUILD_DIR -G "$LUNA_CMAKE_GENERATOR_NAME"
+cmake -S $LUNA_ROOT -B $LUNA_BUILD_DIR -G "$LUNA_CMAKE_GENERATOR_NAME" -DLIBC_BOOTSTRAP=1
 cmake --build $LUNA_BUILD_DIR --target libc
 
 make all-target-libstdc++-v3 CXXFLAGS_FOR_TARGET="-fno-exceptions" -j$(nproc)