THE GREAT CEEIFICATION EVENT

This is a total conversion of SciTECO to plain C (GNU C11).
The chance was taken to improve a lot of internal datastructures,
fix fundamental bugs and lay the foundations of future features.
The GTK user interface is now in an useable state!
All changes have been squashed together.

The language itself has almost not changed at all, except for:

* Detection of string terminators (usually Escape) now takes
  the string building characters into account.
  A string is only terminated outside of string building characters.
  In other words, you can now for instance write
  I^EQ[Hello$world]$
  This removes one of the last bits of shellisms which is out of
  place in SciTECO where no tokenization/lexing is performed.
  Consequently, the current termination character can also be
  escaped using ^Q/^R.
  This is used by auto completions to make sure that strings
  are inserted verbatim and without unwanted sideeffects.
* All strings can now safely contain null-characters
  (see also: 8-bit cleanliness).
  The null-character itself (^@) is not (yet) a valid SciTECO
  command, though.

An incomplete list of changes:

* We got rid of the BSD headers for RB trees and lists/queues.
  The problem with them was that they used a form of metaprogramming
  only to gain a bit of type safety. It also resulted in less
  readble code. This was a C++ desease.
  The new code avoids metaprogramming only to gain type safety.
  The BSD tree.h has been replaced by rb3ptr by Jens Stimpfle
  (https://github.com/jstimpfle/rb3ptr).
  This implementation is also more memory efficient than BSD's.
  The BSD list.h and queue.h has been replaced with a custom
  src/list.h.
* Fixed crashes, performance issues and compatibility issues with
  the Gtk 3 User Interface.
  It is now more or less ready for general use.
  The GDK lock is no longer used to avoid using deprecated functions.
  On the downside, the new implementation (driving the Gtk event loop
  stepwise) is even slower than the old one.
  A few glitches remain (see TODO), but it is hoped that they will
  be resolved by the Scintilla update which will be performed soon.
* A lot of program units have been split up, so they are shorter
  and easier to maintain: core-commands.c, qreg-commands.c,
  goto-commands.c, file-utils.h.
* Parser states are simply structs of callbacks now.
  They still use a kind of polymorphy using a preprocessor trick.
  TECO_DEFINE_STATE() takes an initializer list that will be
  merged with the default list of field initializers.
  To "subclass" states, you can simply define new macros that add
  initializers to existing macros.
* Parsers no longer have a "transitions" table but the input_cb()
  may use switch-case statements.
  There are also teco_machine_main_transition_t now which can
  be used to implement simple transitions. Additionally, you
  can specify functions to execute during transitions.
  This largely avoids long switch-case-statements.
* Parsers are embeddable/reusable now, at least in parse-only mode.
  This does not currently bring any advantages but may later
  be used to write a Scintilla lexer for TECO syntax highlighting.
  Once parsers are fully embeddable, it will also be possible
  to run TECO macros in a kind of coroutine which would allow
  them to process string arguments in real time.
* undo.[ch] still uses metaprogramming extensively but via
  the C preprocessor of course. On the downside, most undo
  token generators must be initiated explicitly (theoretically
  we could have used embedded functions / trampolines to
  instantiate automatically but this has turned out to be
  dangereous).
  There is a TECO_DEFINE_UNDO_CALL() to generate closures for
  arbitrary functions now (ie. to call an arbitrary function
  at undo-time). This simplified a lot of code and is much
  shorter than manually pushing undo tokens in many cases.
* Instead of the ridiculous C++ Curiously Recurring Template
  Pattern to achieve static polymorphy for user interface
  implementations, we now simply declare all functions to
  implement in interface.h and link in the implementations.
  This is possible since we no longer hace to define
  interface subclasses (all state is static variables in
  the interface's *.c files).
* Headers are now significantly shorter than in C++ since
  we can often hide more of our "class" implementations.
* Memory counting is based on dlmalloc for most platforms now.
  Unfortunately, there is no malloc implementation that
  provides an efficient constant-time memory counter that
  is guaranteed to decrease when freeing memory.
  But since we use a defined malloc implementation now,
  malloc_usable_size() can be used safely for tracking memory use.
  malloc() replacement is very tricky on Windows, so we
  use a poll thread on Windows. This can also be enabled
  on other supported platforms using --disable-malloc-replacement.
  All in all, I'm still not pleased with the state of memory
  limiting. It is a mess.
* Error handling uses GError now. This has the advantage that
  the GError codes can be reused once we support error catching
  in the SciTECO language.
* Added a few more test suite cases.
* Haiku is no longer supported as builds are instable and
  I did not manage to debug them - quite possibly Haiku bugs
  were responsible.
* Glib v2.44 or later are now required.
  The GTK UI requires Gtk+ v3.12 or later now.
  The GtkFlowBox fallback and sciteco-wrapper workaround are
  no longer required.
* We now extensively use the GCC/Clang-specific g_auto
  feature (automatic deallocations when leaving the current
  code block).
* Updated copyright to 2021.
  SciTECO has been in continuous development, even though there
  have been no commits since 2018.
* Since these changes are so significant, the target release has
  been set to v2.0.
  It is planned that beginning with v3.0, the language will be
  kept stable.

1 files changed, 123 insertions, 323 deletions

diff --git a/src/interface.h b/src/interface.h
index 607a42c..c396225 100644
--- a/src/interface.h
+++ b/src/interface.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012-2017 Robin Haberkorn
+ * Copyright (C) 2012-2021 Robin Haberkorn
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -14,9 +14,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-
-#ifndef __INTERFACE_H
-#define __INTERFACE_H
+#pragma once
 
 #include <stdarg.h>
 #include <signal.h>
@@ -25,349 +23,151 @@
 
 #include <Scintilla.h>
 
-#include "memory.h"
-#include "undo.h"
-#include "error.h"
-
-namespace SciTECO {
-
-/* avoid include dependency conflict */
-class QRegister;
-class Buffer;
-class Cmdline;
-extern sig_atomic_t sigint_occurred;
+#include "sciteco.h"
+#include "qreg.h"
+#include "ring.h"
+#include "cmdline.h"
+#include "view.h"
 
 /**
- * Base class for all SciTECO views. This is a minimal
- * abstraction where the implementor only has to provide
- * a method for dispatching Scintilla messages.
- * Everything else is handled by other SciTECO classes.
+ * @file
+ * Abstract user interface.
  *
- * This interface employs the Curiously Recurring Template
- * Pattern (CRTP). To implement it, one must derive from
- * View<DerivedClass>. The methods to implement actually
- * have an "_impl" suffix so as to avoid infinite recursion
- * if an implementation is missing.
- * Externally however, the methods as given in this interface
- * may be called.
+ * Interface of all SciTECO user interfaces (e.g. Curses or GTK+).
+ * All functions that must be provided are marked with the \@pure tag.
  *
- * The CRTP has a runtime overhead at low optimization levels
- * (additional non-inlined calls), but should provide a
- * significant performance boost when inlining is enabled.
- *
- * Note that not all methods have to be defined in the
- * class. Explicit template instantiation is used to outsource
- * base-class implementations to interface.cpp.
+ * @note
+ * We do not provide default implementations for any of the interface
+ * functions by declaring them "weak" since this is a non-portable linker
+ * feature.
  */
-template <class ViewImpl>
-class View : public Object {
-	inline ViewImpl &
-	impl(void)
-	{
-		return *(ViewImpl *)this;
-	}
-
-	class UndoTokenMessage : public UndoToken {
-		ViewImpl &view;
 
-		unsigned int iMessage;
-		uptr_t wParam;
-		sptr_t lParam;
+/** @protected */
+extern teco_view_t *teco_interface_current_view;
 
-	public:
-		UndoTokenMessage(ViewImpl &_view, unsigned int _iMessage,
-				 uptr_t _wParam = 0, sptr_t _lParam = 0)
-				: view(_view), iMessage(_iMessage),
-				  wParam(_wParam), lParam(_lParam) {}
+/** @pure */
+void teco_interface_init(void);
 
-		void
-		run(void)
-		{
-			view.ssm(iMessage, wParam, lParam);
-		}
-	};
+/** @pure */
+GOptionGroup *teco_interface_get_options(void);
 
-	class UndoTokenSetRepresentations : public UndoToken {
-		ViewImpl &view;
+/** @pure makes sense only on Curses */
+void teco_interface_init_color(guint color, guint32 rgb);
 
-	public:
-		UndoTokenSetRepresentations(ViewImpl &_view)
-		                           : view(_view) {}
+typedef enum {
+	TECO_MSG_USER,
+	TECO_MSG_INFO,
+	TECO_MSG_WARNING,
+	TECO_MSG_ERROR
+} teco_msg_t;
 
-		void
-		run(void)
-		{
-			view.set_representations();
-		}
-	};
+/** @pure */
+void teco_interface_vmsg(teco_msg_t type, const gchar *fmt, va_list ap);
 
-public:
-	/*
-	 * called after Interface initialization.
-	 * Should call setup()
-	 */
-	inline void
-	initialize(void)
-	{
-		impl().initialize_impl();
-	}
+static inline void G_GNUC_PRINTF(2, 3)
+teco_interface_msg(teco_msg_t type, const gchar *fmt, ...)
+{
+	va_list ap;
 
-	inline sptr_t
-	ssm(unsigned int iMessage,
-	    uptr_t wParam = 0, sptr_t lParam = 0)
-	{
-		return impl().ssm_impl(iMessage, wParam, lParam);
-	}
+	va_start(ap, fmt);
+	teco_interface_vmsg(type, fmt, ap);
+	va_end(ap);
+}
 
-	inline void
-	undo_ssm(unsigned int iMessage,
-		 uptr_t wParam = 0, sptr_t lParam = 0)
-	{
-		undo.push<UndoTokenMessage>(impl(), iMessage, wParam, lParam);
-	}
+/** @pure */
+void teco_interface_msg_clear(void);
 
-	void set_representations(void);
-	inline void
-	undo_set_representations(void)
-	{
-		undo.push<UndoTokenSetRepresentations>(impl());
-	}
+/** @pure */
+void teco_interface_show_view(teco_view_t *view);
+void undo__teco_interface_show_view(teco_view_t *);
 
-	inline void
-	set_scintilla_undo(bool state)
-	{
-		ssm(SCI_EMPTYUNDOBUFFER);
-		ssm(SCI_SETUNDOCOLLECTION, state);
-	}
+static inline sptr_t
+teco_interface_ssm(unsigned int iMessage, uptr_t wParam, sptr_t lParam)
+{
+	return teco_view_ssm(teco_interface_current_view, iMessage, wParam, lParam);
+}
 
-protected:
-	void setup(void);
-};
-
-/**
- * Base class and interface of all SciTECO user interfaces
- * (e.g. Curses or GTK+).
- *
- * This uses the same Curiously Recurring Template Pattern (CRTP)
- * as the View interface above, as there is only one type of
- * user interface at runtime.
+/*
+ * NOTE: You could simply call undo__teco_view_ssm(teco_interface_current_view, ...).
+ * undo__teco_interface_ssm(...) exists for brevity and aestethics.
  */
-template <class InterfaceImpl, class ViewImpl>
-class Interface : public Object {
-	inline InterfaceImpl &
-	impl(void)
-	{
-		return *(InterfaceImpl *)this;
-	}
-
-	class UndoTokenShowView : public UndoToken {
-		ViewImpl *view;
-
-	public:
-		UndoTokenShowView(ViewImpl *_view)
-		                 : view(_view) {}
-
-		void run(void);
-	};
-
-	template <class Type>
-	class UndoTokenInfoUpdate : public UndoToken {
-		const Type *obj;
-
-	public:
-		UndoTokenInfoUpdate(const Type *_obj)
-				   : obj(_obj) {}
-
-		void run(void);
-	};
-
-protected:
-	ViewImpl *current_view;
-
-public:
-	Interface() : current_view(NULL) {}
-
-	/* default implementation */
-	inline GOptionGroup *
-	get_options(void)
-	{
-		return NULL;
-	}
-
-	/* default implementation */
-	inline void init(void) {}
-
-	/* makes sense only on Curses */
-	inline void init_color(guint color, guint32 rgb) {}
+void undo__teco_interface_ssm(unsigned int, uptr_t, sptr_t);
 
-	enum MessageType {
-		MSG_USER,
-		MSG_INFO,
-		MSG_WARNING,
-		MSG_ERROR
-	};
-	inline void
-	vmsg(MessageType type, const gchar *fmt, va_list ap)
-	{
-		impl().vmsg_impl(type, fmt, ap);
-	}
-	inline void
-	msg(MessageType type, const gchar *fmt, ...) G_GNUC_PRINTF(3, 4)
-	{
-		va_list ap;
+/** @pure */
+void teco_interface_info_update_qreg(const teco_qreg_t *reg);
+/** @pure */
+void teco_interface_info_update_buffer(const teco_buffer_t *buffer);
 
-		va_start(ap, fmt);
-		vmsg(type, fmt, ap);
-		va_end(ap);
-	}
-	/* default implementation */
-	inline void msg_clear(void) {}
+#define teco_interface_info_update(X) \
+	(_Generic((X), teco_qreg_t *         : teco_interface_info_update_qreg, \
+	               const teco_qreg_t *   : teco_interface_info_update_qreg, \
+	               teco_buffer_t *       : teco_interface_info_update_buffer, \
+	               const teco_buffer_t * : teco_interface_info_update_buffer)(X))
 
-	inline void
-	show_view(ViewImpl *view)
-	{
-		impl().show_view_impl(view);
-	}
-	inline void
-	undo_show_view(ViewImpl *view)
-	{
-		undo.push<UndoTokenShowView>(view);
-	}
+void undo__teco_interface_info_update_qreg(const teco_qreg_t *);
+void undo__teco_interface_info_update_buffer(const teco_buffer_t *);
 
-	inline ViewImpl *
-	get_current_view(void)
-	{
-		return current_view;
-	}
+/** @pure */
+void teco_interface_cmdline_update(const teco_cmdline_t *cmdline);
 
-	inline sptr_t
-	ssm(unsigned int iMessage, uptr_t wParam = 0, sptr_t lParam = 0)
-	{
-		return current_view->ssm(iMessage, wParam, lParam);
-	}
-	inline void
-	undo_ssm(unsigned int iMessage,
-	         uptr_t wParam = 0, sptr_t lParam = 0)
-	{
-		current_view->undo_ssm(iMessage, wParam, lParam);
-	}
-
-	/*
-	 * NOTE: could be rolled into a template, but
-	 * this way it is explicit what must be implemented
-	 * by the deriving class.
-	 */
-	inline void
-	info_update(const QRegister *reg)
-	{
-		impl().info_update_impl(reg);
-	}
-	inline void
-	info_update(const Buffer *buffer)
-	{
-		impl().info_update_impl(buffer);
-	}
-
-	inline void
-	undo_info_update(const QRegister *reg)
-	{
-		undo.push<UndoTokenInfoUpdate<QRegister>>(reg);
-	}
-	inline void
-	undo_info_update(const Buffer *buffer)
-	{
-		undo.push<UndoTokenInfoUpdate<Buffer>>(buffer);
-	}
-
-	inline void
-	cmdline_update(const Cmdline *cmdline)
-	{
-		impl().cmdline_update_impl(cmdline);
-	}
-
-	/* default implementation */
-	inline void
-	set_clipboard(const gchar *name,
-	              const gchar *str = NULL, gssize str_len = -1)
-	{
-		throw Error("Setting clipboard unsupported");
-	}
-
-	/* default implementation */
-	inline gchar *
-	get_clipboard(const gchar *name, gsize *str_len = NULL)
-	{
-		throw Error("Getting clipboard unsupported");
-	}
-
-	enum PopupEntryType {
-		POPUP_PLAIN,
-		POPUP_FILE,
-		POPUP_DIRECTORY
-	};
-	inline void
-	popup_add(PopupEntryType type,
-	          const gchar *name, bool highlight = false)
-	{
-		impl().popup_add_impl(type, name, highlight);
-	}
-	inline void
-	popup_show(void)
-	{
-		impl().popup_show_impl();
-	}
-	inline bool
-	popup_is_shown(void)
-	{
-		return impl().popup_is_shown_impl();
-	}
-	inline void
-	popup_clear(void)
-	{
-		impl().popup_clear_impl();
-	}
-
-	/* default implementation */
-	inline bool
-	is_interrupted(void)
-	{
-		return sigint_occurred != FALSE;
-	}
-
-	/* main entry point */
-	inline void
-	event_loop(void)
-	{
-		impl().event_loop_impl();
-	}
-
-	/*
-	 * Interfacing to the external SciTECO world
-	 */
-protected:
-	void stdio_vmsg(MessageType type, const gchar *fmt, va_list ap);
-public:
-	void process_notify(SCNotification *notify);
-};
-
-} /* namespace SciTECO */
-
-#ifdef INTERFACE_GTK
-#include "interface-gtk/interface-gtk.h"
-#elif defined(INTERFACE_CURSES)
-#include "interface-curses/interface-curses.h"
-#else
-#error No interface selected!
-#endif
-
-namespace SciTECO {
+/** @pure */
+gboolean teco_interface_set_clipboard(const gchar *name, const gchar *str, gsize str_len,
+                                      GError **error);
+void teco_interface_undo_set_clipboard(const gchar *name, gchar *str, gsize len);
+/**
+ * Semantics are compatible with teco_qreg_vtable_t::get_string() since that is the
+ * main user of this function.
+ *
+ * @pure
+ */
+gboolean teco_interface_get_clipboard(const gchar *name, gchar **str, gsize *len, GError **error);
+
+typedef enum {
+	TECO_POPUP_PLAIN,
+	TECO_POPUP_FILE,
+	TECO_POPUP_DIRECTORY
+} teco_popup_entry_type_t;
+
+/** @pure */
+void teco_interface_popup_add(teco_popup_entry_type_t type,
+                              const gchar *name, gsize name_len, gboolean highlight);
+/** @pure */
+void teco_interface_popup_show(void);
+/** @pure */
+gboolean teco_interface_popup_is_shown(void);
+/** @pure */
+void teco_interface_popup_clear(void);
+
+/** @pure */
+gboolean teco_interface_is_interrupted(void);
+
+/** @pure main entry point */
+gboolean teco_interface_event_loop(GError **error);
 
-/* object defined in main.cpp */
-extern InterfaceCurrent interface;
+/*
+ * Interfacing to the external SciTECO world
+ */
+/** @protected */
+void teco_interface_stdio_vmsg(teco_msg_t type, const gchar *fmt, va_list ap);
+void teco_interface_process_notify(struct SCNotification *notify);
 
-extern template class View<ViewCurrent>;
-extern template class Interface<InterfaceCurrent, ViewCurrent>;
+/** @pure */
+void teco_interface_cleanup(void);
 
-} /* namespace SciTECO */
+/*
+ * The following functions are here for lack of a better place.
+ * They could also be in sciteco.h, but only if declared as non-inline
+ * since sciteco.h should not depend on interface.h.
+ */
 
-#endif
+static inline gboolean
+teco_validate_pos(teco_int_t n)
+{
+	return 0 <= n && n <= teco_interface_ssm(SCI_GETLENGTH, 0, 0);
+}
+
+static inline gboolean
+teco_validate_line(teco_int_t n)
+{
+	return 0 <= n && n < teco_interface_ssm(SCI_GETLINECOUNT, 0, 0);
+}