fix make for a21, PIDs are always ints, linter things

.clang-tidy

@@ -1,6 +1,6 @@
 FormatStyle: google
 HeaderFilterRegex: '.*'
-WarningsAsErrors: 'readability*'
+#WarningsAsErrors: 'readability*'
 Checks: >
   google-readability-casting,
   google-explicit-constructor,
@@ -9,6 +9,7 @@ Checks: >
   -readability-else-after-return,
   -readability-function-cognitive-complexity
   -readability-identifier-length,
+  -readability-implicit-bool-conversion,
   -readability-magic-numbers,
   bugprone*,
   -bugprone-easily-swappable-parameters,
@@ -19,8 +20,11 @@ Checks: >
   -cppcoreguidelines-avoid-do-while,
   -cppcoreguidelines-avoid-magic-numbers,
   -cppcoreguidelines-avoid-non-const-global-variables,
+  -cppcoreguidelines-non-private-member-variables-in-classes,
   -cppcoreguidelines-owning-memory,
   -cppcoreguidelines-pro-*,
 CheckOptions:
   readability-simplify-boolean-expr.IgnoreMacros: 'true'
-  readability-identifier-length.IgnoreNames: 'g,me'
+  readability-identifier-length.IgnoredVariableNames: '^(g|id|me)$'
+  readability-identifier-length.IgnoredParameterNames: '^(id|ms|p[1-5])$'
+  readability-identifier-length.IgnoredLoopCounterNames: '.*'

kernel/arch/idt.cc

@@ -10,13 +10,9 @@ constinit struct InterruptDescriptor idt[256] = {};
 // Struct used for loading (the address of) the Interrupt Descriptor Table into
 // the IDT-Register
 struct Register {
-	uint16_t limit;	 // Address of the last valid byte (relative to base)
-	struct InterruptDescriptor* base;
-	explicit Register(uint8_t max = 255) {
-		limit =
-			(max + static_cast<uint16_t>(1)) * sizeof(InterruptDescriptor) - 1;
-		base = idt;
-	}
+	uint16_t limit =
+		sizeof(idt) - 1;  // Address of the last valid byte (relative to base)
+	struct InterruptDescriptor* base = idt;
 } __attribute__((packed));
 
 static_assert(sizeof(InterruptDescriptor) == 16,
@@ -26,11 +22,11 @@ static_assert(alignof(decltype(idt)) % 8 == 0, "IDT must be 8 byte aligned!");
 
 void load() {
 	// Create structure required for writing to idtr and load via lidt
-	Register idtr(Core::Interrupt::VECTORS - 1);
+	Register idtr;
 	asm volatile("lidt %0\n\t" ::"m"(idtr));
 }
 
 void set(Core::Interrupt::Vector vector, InterruptDescriptor descriptor) {
-	idt[(uint8_t)vector] = descriptor;
+	idt[static_cast<uint8_t>(vector)] = descriptor;
 }
 }  // namespace IDT

kernel/debug/assert.cc

@@ -1,7 +1,7 @@
 #include "assert.h"
 
 #include "../arch/core.h"
-#include "output.h"
+#include "./output.h"
 
 [[noreturn]] void assertion_failed(const char* exp, const char* func,
 								   const char* file, int line) {

kernel/debug/assert.h

@@ -15,7 +15,7 @@
  */
 
 #pragma once
-#include "../types.h"
+#include "types.h"
 
 #ifndef STRINGIFY
 /*! \def STRINGIFY(S)

kernel/object/queue.h

@@ -25,18 +25,22 @@ class Queue {
 	/// Function pointer to the get_link function, called whenever the
 	/// next pointer array is referenced
 	const NextFunc get_link = default_get_link;
-	/// head points to the first element (the one returned on first dequeue).
-	/// Can be nullptr if the queue is empty.
+	/// `head` points to the first element (the one returned on first dequeue).
+	/// Can be `nullptr` if the queue is empty.
 	T* head = nullptr;
-	/// tail points to the last element (the one last added).
-	/// Is only valid if head != nullptr
+	/// `tail` points to the last element (the one last added).
+	/// Is only valid if `head != nullptr`.
 	T* tail = nullptr;
 
 	// Prevent copies and assignments
 	Queue(const Queue&) = delete;
+	Queue(Queue&&) = delete;
 	Queue& operator=(const Queue&) = delete;
+	Queue& operator=(Queue&&) = delete;
 
    public:
+	~Queue() = default;
+
 	/*! \brief Minimal forward iterator
 	 * You can use this iterator to iterate the queue like a normal STL
 	 * container. It only supports forward iteration, since the queue is single
@@ -44,11 +48,11 @@ class Queue {
 	 */
 	class Iterator {
 	   private:
-		Queue<T>& queue;
+		Queue<T>* queue;
 		T* current;
 		friend class Queue<T>;
 		Iterator(Queue<T>& queue, T* current)
-			: queue(queue), current(current) {}
+			: queue(&queue), current(current) {}
 
 	   public:
 		Iterator operator+(unsigned num) {
@@ -57,21 +61,21 @@ class Queue {
 			}
 			T* temp = current;
 			while (num--) {
-				temp = queue.next(*temp);
+				temp = queue->next(*temp);
 			}
-			return Iterator(queue, temp);
+			return Iterator(*queue, temp);
 		}
 
 		// pre increment
 		Iterator& operator++() {
-			current = queue.next(*current);
+			current = queue->next(*current);
 			return *this;
 		}
 
 		// post increment
 		Iterator operator++(int) {
 			auto temp = Iterator(queue, current);
-			current = queue.next(*current);
+			current = queue->next(*current);
 			return temp;
 		}
 
@@ -84,8 +88,6 @@ class Queue {
 		bool operator!=(const Iterator& other) { return !(*this == other); }
 	};
 
-	constexpr Queue(Queue&&) = default;
-
 	/*! \brief Constructor
 	 *	\param[in] get_link A function pointer to the get_link, i.e. a function
 	 *						which returns a pointer to the next-pointer of an
@@ -97,11 +99,10 @@ class Queue {
 			   "get_link function pointer must not be nullptr!");
 	}
 
-	/*! \brief Enqueues the provided item at the end of the queue. If the
-	 *element is already contained in the queue, false will be returned
-	 * \param[in] item	element to be appended (enqueued).
-	 * \return false if the element already was enqueued (and nothing was done)
-	 *		   or not (and it is now enqueued, then true)
+	/*! \brief Enqueues the provided item at the end of the queue.
+	 * \param[in] item	Element to be appended (enqueued).
+	 * \return `false` if the element already was already in this (or a
+	 * different) queue (and nothing was done), `true` otherwise.
 	 */
 	bool enqueue(T& item) {
 		T** nextptr = get_link(item);
@@ -214,7 +215,7 @@ class Queue {
 	T* remove(T* that) {
 		if (!that) return nullptr;
 		T* cur = head;
-		T** next_link;
+		T** next_link = nullptr;
 
 		if (head == that) {
 			head = *get_link(*head);
@@ -258,14 +259,14 @@ class Queue {
  * the pointer.
  */
 template <class T>
-OutputStream& operator<<(OutputStream& os, Queue<T>& queue) {
-	os << "{";
+OutputStream& operator<<(OutputStream& out, Queue<T>& queue) {
+	out << "{";
 	for (typename Queue<T>::Iterator it = queue.begin(); it != queue.end();
 		 ++it) {
-		os << *it;
+		out << *it;
 		if (it + 1 != queue.end()) {
-			os << ", ";
+			out << ", ";
 		}
 	}
-	return os << "}";
+	return out << "}";
 }

kernel/sync/message.h

@@ -3,42 +3,13 @@
 #include "../types.h"
 
 struct Message {
-	const size_t pid;  ///< Sender Thread ID of message
+	int sender;	 ///< Sender Thread ID of message
 
-	const uintptr_t sbuffer;  ///< Send buffer
-	const size_t ssize;		  ///< Send buffer size
+	uintptr_t sbuffer;	///< Send buffer
+	size_t ssize;		///< Send buffer size
 
-	const uintptr_t rbuffer;  ///< Receive buffer
-	const size_t rsize;		  ///< Receive buffer size
+	uintptr_t rbuffer;	///< Receive buffer
+	size_t rsize;		///< Receive buffer size
 
 	Message *queue_link = nullptr;	///< Next message in the message queue
-
-	/*! \brief Constructor
-	 *  \param pid     Sender Thread ID of message
-	 *  \param sbuffer Send buffer
-	 *  \param ssize   Send buffer size
-	 *  \param rbuffer Receive buffer
-	 *  \param rsize   Receive buffer size
-	 */
-	explicit Message(int pid, uintptr_t sbuffer = 0, size_t ssize = 0,
-					 uintptr_t rbuffer = 0, size_t rsize = 0)
-		: pid(pid),
-		  sbuffer(sbuffer),
-		  ssize(ssize),
-		  rbuffer(rbuffer),
-		  rsize(rsize) {}
-
-	/*! \brief Helper to retrieve (and remove) a message from the queue
-	 *  \param pid   Thread id of message
-	 *  \param queue Queue with message
-	 *  \return Pointer to message or nullptr
-	 */
-	static Message *dequeueByPID(size_t pid, Queue<Message> &queue) {
-		for (Message *m : queue) {
-			if (m->pid == pid) {
-				return queue.remove(m);
-			}
-		}
-		return nullptr;
-	}
 };

kernel/sync/semaphore.h

@@ -24,15 +24,17 @@ class Thread;
 class Semaphore {
 	// Prevent copies and assignments
 	Semaphore(const Semaphore&) = delete;
+	Semaphore(Semaphore&&) = delete;
 	Semaphore& operator=(const Semaphore&) = delete;
+	Semaphore& operator=(Semaphore&&) = delete;
 	unsigned counter;
 	Queue<Thread> waiting;
 
    public:
-	/*! \brief Constructor; initialized the counter with provided value `c`
-	 *  \param c Initial counter value
+	/*! \param init Initial counter value
 	 */
-	explicit Semaphore(unsigned c = 0) : counter(c) {}
+	explicit Semaphore(unsigned init = 0) : counter(init) {}
+	~Semaphore() = default;
 
 	/*! \brief Wait for access to the critical area.
 	 *

kernel/syscall/skeleton.cc

@@ -1,8 +1,6 @@
 #include "syscall/skeleton.h"
 
-#include "debug/kernelpanic.h"
 #include "debug/output.h"
-#include "device/textstream.h"
 #include "interrupt/guard.h"
 #include "sync/semaphore.h"
 #include "thread/scheduler.h"

kernel/syscall/skeleton.h

@@ -22,7 +22,7 @@ void sem_destroy(Vault &vault, size_t id);
 void sem_signal(Vault &vault, size_t id);
 void sem_wait(Vault &vault, size_t id);
 void exit(Vault &vault);
-void kill(Vault &vault, size_t pid);
+void kill(Vault &vault, int pid);
 
 }  // namespace Skeleton
 }  // namespace Syscall

kernel/thread/thread.cc

@@ -6,8 +6,7 @@
 #include "../interrupt/guard.h"
 #include "debug/output.h"
 
-// counter for ID
-static size_t idCounter = 1;
+static int idCounter = 1;  // counter for task IDs
 
 void Thread::kickoff(uintptr_t param1, uintptr_t param2, uintptr_t param3) {
 	Thread *thread = reinterpret_cast<Thread *>(param1);

kernel/thread/thread.h

@@ -28,14 +28,12 @@ class Thread {
 	/*! \brief pointer to the next element of the readylist
 	 */
 	Thread* queue_link;
-
 	friend class Queue<Thread>;
 	friend class Semaphore;
 	/*! \brief Memory reserved for this threads stack
 	 */
 	alignas(16) char reserved_stack_space[STACK_SIZE];
 
-   protected:
 	/*! \brief Context of the thread, used for saving and restoring the register
 	 * values when context switching.
 	 */
@@ -56,17 +54,25 @@ class Thread {
 	 *  \param param1 Thread to be started
 	 *  \param param2 Second parameter (will be used later)
 	 *  \param param3 Third parameter (will be used later)
+	 *
 	 */
 	static void kickoff(uintptr_t param1, uintptr_t param2, uintptr_t param3);
 
    public:
 	/*! \brief Unique thread id */
-	const size_t id;
+	const int id;
 
 	/*! \brief Marker for a dying thread
 	 */
 	volatile bool kill_flag;
 
+	// Naively moving or copying esp. the (user) stack of a thread would be a
+	// bad idea:
+	Thread(const Thread&) = delete;
+	Thread(Thread&&) = delete;
+	Thread& operator=(const Thread&) = delete;
+	Thread& operator=(Thread&&) = delete;
+
 	/*! \brief Constructor
 	 *  Initializes the context using \ref prepareContext with the thread's
 	 * stack space.

kernel/user/app1/appl.cc

@@ -23,7 +23,7 @@ void Application::action() {  // NOLINT
 		// Make sure that we can use kout exclusively due to the hardware cursor
 		// otherwise we'd get a word jumble
 		koutsem.p(Guard::enter().vault());
-		kout.setPos(0U, id);
+		kout.setPos(0U, static_cast<unsigned>(id));
 		kout << i;
 		kout.flush();
 		koutsem.v(Guard::enter().vault());

libsys/assert.h

@@ -0,0 +1,74 @@
+// vim: set noet ts=4 sw=4:
+
+/*! \file
+ * \brief Contains several macros usable for making assertions
+ *
+ * Depending on the type of assertion (either static or at runtime), a failing
+ * assertion will trigger an error. For static assertion, this error will be
+ * shown at compile time and abort compilation. Runtime assertions will trigger
+ * a message containing details about the error occurred and will make the CPU
+ * die.
+ */
+
+/*!
+ * \defgroup debug Debugging functions
+ */
+
+#pragma once
+#include "types.h"
+
+#ifndef STRINGIFY
+/*! \def STRINGIFY(S)
+ * \brief Converts a macro parameter into a string
+ * \ingroup debug
+ * \param S Expression to be converted
+ * \return stringified version of S
+ */
+#define STRINGIFY(S) #S
+#endif
+
+/*! \def assert_size(TYPE, SIZE)
+ * \brief Statically ensure (at compile time) that a data type (or variable)
+ * has the expected size.
+ *
+ * \ingroup debug
+ * \param TYPE The type to be checked
+ * \param SIZE Expected size in bytes
+ */
+#define assert_size(TYPE, SIZE) \
+	static_assert(sizeof(TYPE) == (SIZE), "Wrong size for " STRINGIFY(TYPE))
+
+/*! \def assert(EXP)
+ * \brief Ensure (at execution time) an expression evaluates to `true`, print
+ * an error message and stop the CPU otherwise.
+ *
+ * \ingroup debug
+ * \param EXP The expression to be checked
+ */
+#ifdef NDEBUG
+#define assert(EXP) ((void)0)
+#else
+#define assert(EXP)                                                         \
+	do {                                                                    \
+		if (__builtin_expect(!(EXP), 0)) {                                  \
+			assertion_failed(STRINGIFY(EXP), __func__, __FILE__, __LINE__); \
+		}                                                                   \
+	} while (false)
+
+/*! \brief Handles a failed assertion
+ *
+ * This function will print a message containing further information about the
+ * failed assertion and stops the current CPU permanently.
+ *
+ * \note This function should never be called directly, but only via the macro
+ * `assert`.
+ *
+ *
+ * \param exp Expression that did not hold
+ * \param func Name of the function in which the assertion failed
+ * \param file Name of the file in which the assertion failed
+ * \param line Line in which the assertion failed
+ */
+[[noreturn]] void assertion_failed(const char* exp, const char* func,
+								   const char* file, int line);
+#endif

user/Makefile

@@ -19,14 +19,16 @@ $(APPS): $(BUILDDIR)/init.o
 
 # recipe for compiling imgbuilder
 $(IMGBUILDER): imgbuilder.cc $(MAKEFILE_LIST)
-	@echo "CC		$@"
-	@if test \( ! \( -d $(@D) \) \) ;then mkdir -p $(@D);fi
+	@echo "CXX		$@"
+	@mkdir -p $(@D)
 	$(VERBOSE) $(CXX) -std=c++23 -o $@ $<
 
-# recipe for building the final oostubs image
+.ONESHELL:
+# recipe for building the initrd image
 $(INITRD): $(APPS) $(IMGBUILDER)
 	@echo "IMGBUILD	$@"
-	@if test \( ! \( -d $(@D) \) \) ;then mkdir -p $(@D);fi
+	@mkdir -p $(@D)
+	if [ -z "$(APPS)" ] ; then touch $@ ; exit 0 ; fi
 	$(VERBOSE) $(IMGBUILDER) $(addsuffix $(BUILDDIR)/app.img, $(APPS)) > $@
 
 lint::

user/Makefile.app

@@ -41,7 +41,7 @@ $(BUILDDIR)/app: $(INITOBJ)  $(ASM_OBJECTS) $(CC_OBJECTS) $(LINKER_SCRIPT) $(MAK
 $(BUILDDIR)/app.img: $(BUILDDIR)/app
 	@echo "OBJCOPY		$@"
 	@if ! nm $< | grep "4000000 T start" >/dev/null 2>&1 ; then echo "Symbol 'start' is not first address" ; exit 1 ; fi
-	@if test \( ! \( -d $(@D) \) \) ;then mkdir -p $(@D);fi
+	@mkdir -p $(@D)
 	$(VERBOSE) objcopy -O binary --set-section-flags .bss=alloc,load,contents $< $@
 
 # --------------------------------------------------------------------------

user/imgbuilder.cc

@@ -10,7 +10,7 @@
 #include <print>
 #include <vector>
 
-constexpr size_t block_size = 4096;
+constexpr std::streamsize block_size = 4096;
 const uint8_t zeros[block_size] = {};
 
 template <class... Args>
@@ -20,7 +20,7 @@ static void die(std::format_string<Args...> fmt, Args &&...args) {
 	exit(EXIT_FAILURE);
 }
 
-static void writeBuffer(const void *data, size_t size) {
+static void writeBuffer(const void *data, std::streamsize size) {
 	std::cout.write(reinterpret_cast<const char *>(data), size);
 }
 
@@ -33,35 +33,33 @@ int main(int argc, char *argv[]) {
 		return EXIT_FAILURE;
 	}
 
-	// HEADER: Number of apps + size of each app
-	std::array<uint32_t, block_size / sizeof(uint32_t)> size{0};
-	size[0] = static_cast<uint32_t>(argc - 1);
-
+	// HEADER: Number of apps + size of each app in bytes
+	std::array<uint32_t, block_size / sizeof(uint32_t)> sizes{0};
+	sizes[0] = static_cast<uint32_t>(argc - 1);
 	for (size_t i = 1; i < argc; ++i) {
-		struct stat sb;
-		if (stat(argv[i], &sb) != 0) die("stat");
-		// 4 GB Limit
-		if (sb.st_size >= UINT32_MAX) {
+		struct stat file;
+		if (stat(argv[i], &file) != 0) die("stat");
+		if (file.st_size >= UINT32_MAX) {  // 4 GB Limit
 			errno = EFBIG;
 			die("stat");
 		}
-		size[i] = sb.st_size;
+		sizes[i] = file.st_size;
 	}
-	writeBuffer(size.data(), block_size);
+	writeBuffer(sizes.data(), block_size);
 
 	// DATA: Each App
 	for (size_t i = 1; i < argc; ++i) {
-		std::vector<char> buf(size[i]);
+		std::vector<char> buf(sizes[i]);
 		std::ifstream input(argv[i], std::ios::binary);
 		if (!input) die("fopen");
 
-		input.read(buf.data(), size[i]);
+		input.read(buf.data(), sizes[i]);
 
-		writeBuffer(buf.data(), size[i]);
+		writeBuffer(buf.data(), sizes[i]);
 
 		// Fill to block size, if required
-		if (size[i] % block_size != 0)
-			writeBuffer(zeros, block_size - (size[i] % block_size));
+		if (sizes[i] % block_size != 0)
+			writeBuffer(zeros, block_size - (sizes[i] % block_size));
 	}
 
 	std::cout.flush();