refactoring: split qbuffers.cpp|h into a q-registers (qregisters.cpp) and Buffer ring part (ring.cpp)

12 files changed, 796 insertions, 739 deletions

diff --git a/Makefile b/Makefile
index 91dc300..27eef53 100644
--- a/Makefile
+++ b/Makefile
@@ -53,7 +53,7 @@ ifneq ($(findstring MINGW32,$(OS)),)
 CPPFLAGS+=-Icompat
 endif
 
-MINIMAL_OBJS:=main.o cmdline.o undo.o expressions.o qbuffers.o \
+MINIMAL_OBJS:=main.o cmdline.o undo.o expressions.o qregisters.o ring.o \
 	      parser.o search.o goto.o rbtree.o symbols.o \
 	      interface.a
 
diff --git a/cmdline.cpp b/cmdline.cpp
index 80cd2d7..212722a 100644
--- a/cmdline.cpp
+++ b/cmdline.cpp
@@ -9,7 +9,8 @@
 #include "interface.h"
 #include "expressions.h"
 #include "parser.h"
-#include "qbuffers.h"
+#include "qregisters.h"
+#include "ring.h"
 #include "goto.h"
 #include "undo.h"
 #include "symbols.h"
diff --git a/interface-gtk.cpp b/interface-gtk.cpp
index a55a2c8..7515b2f 100644
--- a/interface-gtk.cpp
+++ b/interface-gtk.cpp
@@ -14,7 +14,8 @@
 #include <ScintillaWidget.h>
 
 #include "sciteco.h"
-#include "qbuffers.h"
+#include "qregisters.h"
+#include "ring.h"
 #include "interface.h"
 #include "interface-gtk.h"
 
diff --git a/interface-ncurses.cpp b/interface-ncurses.cpp
index fe2c7e7..0e08914 100644
--- a/interface-ncurses.cpp
+++ b/interface-ncurses.cpp
@@ -17,7 +17,8 @@
 #include <ScintillaTerm.h>
 
 #include "sciteco.h"
-#include "qbuffers.h"
+#include "qregisters.h"
+#include "ring.h"
 #include "interface.h"
 #include "interface-ncurses.h"
 
diff --git a/main.cpp b/main.cpp
index e23eca8..4526da3 100644
--- a/main.cpp
+++ b/main.cpp
@@ -14,7 +14,8 @@
 #include "interface.h"
 #include "parser.h"
 #include "goto.h"
-#include "qbuffers.h"
+#include "qregisters.h"
+#include "ring.h"
 #include "undo.h"
 
 #ifdef G_OS_UNIX
diff --git a/parser.cpp b/parser.cpp
index bb05d66..5ba96fa 100644
--- a/parser.cpp
+++ b/parser.cpp
@@ -10,7 +10,8 @@
 #include "undo.h"
 #include "expressions.h"
 #include "goto.h"
-#include "qbuffers.h"
+#include "qregisters.h"
+#include "ring.h"
 #include "parser.h"
 #include "symbols.h"
 #include "search.h"
diff --git a/qregisters.cpp b/qregisters.cpp
new file mode 100644
index 0000000..06947f7
--- /dev/null
+++ b/qregisters.cpp
@@ -0,0 +1,522 @@
+#include <string.h>
+#include <bsd/sys/queue.h>
+
+#include <glib.h>
+#include <glib/gprintf.h>
+#include <glib/gstdio.h>
+
+#include <Scintilla.h>
+
+#include "sciteco.h"
+#include "interface.h"
+#include "undo.h"
+#include "parser.h"
+#include "expressions.h"
+#include "ring.h"
+#include "qregisters.h"
+
+namespace States {
+	StatePushQReg		pushqreg;
+	StatePopQReg		popqreg;
+	StateEQCommand		eqcommand;
+	StateLoadQReg		loadqreg;
+	StateCtlUCommand	ctlucommand;
+	StateSetQRegString	setqregstring;
+	StateGetQRegString	getqregstring;
+	StateGetQRegInteger	getqreginteger;
+	StateSetQRegInteger	setqreginteger;
+	StateIncreaseQReg	increaseqreg;
+	StateMacro		macro;
+	StateCopyToQReg		copytoqreg;
+}
+
+namespace QRegisters {
+	QRegisterTable		globals;
+	QRegisterTable		*locals = NULL;
+	QRegister		*current = NULL;
+
+	static QRegisterStack	stack;
+}
+
+static QRegister *register_argument = NULL;
+
+static inline void
+current_edit(void)
+{
+	if (ring.current)
+		ring.current->edit();
+	else if (QRegisters::current)
+		QRegisters::current->edit();
+}
+
+void
+QRegisterData::set_string(const gchar *str)
+{
+	edit();
+	dot = 0;
+
+	interface.ssm(SCI_BEGINUNDOACTION);
+	interface.ssm(SCI_SETTEXT, 0, (sptr_t)(str ? : ""));
+	interface.ssm(SCI_ENDUNDOACTION);
+
+	current_edit();
+}
+
+void
+QRegisterData::undo_set_string(void)
+{
+	/* set_string() assumes that dot has been saved */
+	current_save_dot();
+
+	if (!must_undo)
+		return;
+
+	if (ring.current)
+		ring.current->undo_edit();
+	else if (QRegisters::current)
+		QRegisters::current->undo_edit();
+
+	undo.push_var<gint>(dot);
+	undo.push_msg(SCI_UNDO);
+
+	undo_edit();
+}
+
+void
+QRegisterData::append_string(const gchar *str)
+{
+	if (!str)
+		return;
+
+	edit();
+
+	interface.ssm(SCI_BEGINUNDOACTION);
+	interface.ssm(SCI_APPENDTEXT, strlen(str), (sptr_t)str);
+	interface.ssm(SCI_ENDUNDOACTION);
+
+	current_edit();
+}
+
+gchar *
+QRegisterData::get_string(void)
+{
+	gint size;
+	gchar *str;
+
+	current_save_dot();
+	edit();
+
+	size = interface.ssm(SCI_GETLENGTH) + 1;
+	str = (gchar *)g_malloc(size);
+	interface.ssm(SCI_GETTEXT, size, (sptr_t)str);
+
+	current_edit();
+
+	return str;
+}
+
+void
+QRegisterData::edit(void)
+{
+	interface.ssm(SCI_SETDOCPOINTER, 0, (sptr_t)get_document());
+	interface.ssm(SCI_GOTOPOS, dot);
+}
+
+void
+QRegisterData::undo_edit(void)
+{
+	if (!must_undo)
+		return;
+
+	undo.push_msg(SCI_GOTOPOS, dot);
+	undo.push_msg(SCI_SETDOCPOINTER, 0, (sptr_t)get_document());
+}
+
+void
+QRegister::edit(void)
+{
+	QRegisterData::edit();
+	interface.info_update(this);
+}
+
+void
+QRegister::undo_edit(void)
+{
+	if (!must_undo)
+		return;
+
+	interface.undo_info_update(this);
+	QRegisterData::undo_edit();
+}
+
+void
+QRegister::execute(bool locals) throw (State::Error)
+{
+	gchar *str = get_string();
+
+	try {
+		Execute::macro(str, locals);
+	} catch (...) {
+		g_free(str);
+		throw; /* forward */
+	}
+
+	g_free(str);
+}
+
+bool
+QRegister::load(const gchar *filename)
+{
+	gchar *contents;
+	gsize size;
+
+	/* FIXME: prevent excessive allocations by reading file into buffer */
+	if (!g_file_get_contents(filename, &contents, &size, NULL))
+		return false;
+
+	edit();
+	dot = 0;
+
+	interface.ssm(SCI_BEGINUNDOACTION);
+	interface.ssm(SCI_CLEARALL);
+	interface.ssm(SCI_APPENDTEXT, size, (sptr_t)contents);
+	interface.ssm(SCI_ENDUNDOACTION);
+
+	g_free(contents);
+
+	current_edit();
+
+	return true;
+}
+
+gint64
+QRegisterBufferInfo::get_integer(void)
+{
+	gint64 id = 1;
+
+	if (!ring.current)
+		return 0;
+
+	for (Buffer *buffer = ring.first();
+	     buffer != ring.current;
+	     buffer = buffer->next())
+		id++;
+
+	return id;
+}
+
+gchar *
+QRegisterBufferInfo::get_string(void)
+{
+	gchar *filename = ring.current ? ring.current->filename : NULL;
+
+	return g_strdup(filename ? : "");
+}
+
+void
+QRegisterBufferInfo::edit(void)
+{
+	gchar *filename = ring.current ? ring.current->filename : NULL;
+
+	QRegister::edit();
+
+	interface.ssm(SCI_BEGINUNDOACTION);
+	interface.ssm(SCI_SETTEXT, 0, (sptr_t)(filename ? : ""));
+	interface.ssm(SCI_ENDUNDOACTION);
+
+	undo.push_msg(SCI_UNDO);
+}
+
+void
+QRegisterTable::initialize(void)
+{
+	/* general purpose registers */
+	for (gchar q = 'A'; q <= 'Z'; q++)
+		initialize(q);
+	for (gchar q = '0'; q <= '9'; q++)
+		initialize(q);
+}
+
+void
+QRegisterTable::edit(QRegister *reg)
+{
+	current_save_dot();
+	reg->edit();
+
+	ring.current = NULL;
+	QRegisters::current = reg;
+}
+
+void
+QRegisterStack::UndoTokenPush::run(void)
+{
+	SLIST_INSERT_HEAD(&stack->head, entry, entries);
+	entry = NULL;
+}
+
+void
+QRegisterStack::UndoTokenPop::run(void)
+{
+	Entry *entry = SLIST_FIRST(&stack->head);
+
+	SLIST_REMOVE_HEAD(&stack->head, entries);
+	delete entry;
+}
+
+void
+QRegisterStack::push(QRegister *reg)
+{
+	Entry *entry = new Entry();
+
+	entry->set_integer(reg->get_integer());
+	if (reg->string) {
+		gchar *str = reg->get_string();
+		entry->set_string(str);
+		g_free(str);
+	}
+	entry->dot = reg->dot;
+
+	SLIST_INSERT_HEAD(&head, entry, entries);
+	undo.push(new UndoTokenPop(this));
+}
+
+bool
+QRegisterStack::pop(QRegister *reg)
+{
+	Entry *entry = SLIST_FIRST(&head);
+	QRegisterData::document *string;
+
+	if (!entry)
+		return false;
+
+	reg->undo_set_integer();
+	reg->set_integer(entry->get_integer());
+
+	/* exchange document ownership between Stack entry and Q-Register */
+	string = reg->string;
+	if (reg->must_undo)
+		undo.push_var(reg->string);
+	reg->string = entry->string;
+	undo.push_var(entry->string);
+	entry->string = string;
+
+	if (reg->must_undo)
+		undo.push_var(reg->dot);
+	reg->dot = entry->dot;
+
+	SLIST_REMOVE_HEAD(&head, entries);
+	/* pass entry ownership to undo stack */
+	undo.push(new UndoTokenPush(this, entry));
+
+	return true;
+}
+
+QRegisterStack::~QRegisterStack()
+{
+	Entry *entry, *next;
+
+	SLIST_FOREACH_SAFE(entry, &head, entries, next)
+		delete entry;
+}
+
+void
+QRegisters::hook(Hook type)
+{
+	if (!(Flags::ed & Flags::ED_HOOKS))
+		return;
+
+	expressions.push(type);
+	globals["0"]->execute();
+}
+
+/*
+ * Command states
+ */
+
+State *
+StatePushQReg::got_register(QRegister *reg) throw (Error)
+{
+	BEGIN_EXEC(&States::start);
+
+	QRegisters::stack.push(reg);
+
+	return &States::start;
+}
+
+State *
+StatePopQReg::got_register(QRegister *reg) throw (Error)
+{
+	BEGIN_EXEC(&States::start);
+
+	if (!QRegisters::stack.pop(reg))
+		throw Error("Q-Register stack is empty");
+
+	return &States::start;
+}
+
+State *
+StateEQCommand::got_register(QRegister *reg) throw (Error)
+{
+	BEGIN_EXEC(&States::loadqreg);
+	register_argument = reg;
+	return &States::loadqreg;
+}
+
+State *
+StateLoadQReg::done(const gchar *str) throw (Error)
+{
+	BEGIN_EXEC(&States::start);
+
+	if (*str) {
+		register_argument->undo_load();
+		if (!register_argument->load(str))
+			throw Error("Cannot load \"%s\" into Q-Register \"%s\"",
+				    str, register_argument->name);
+	} else {
+		if (ring.current)
+			ring.undo_edit();
+		else /* QRegisters::current != NULL */
+			QRegisters::undo_edit();
+		QRegisters::globals.edit(register_argument);
+	}
+
+	return &States::start;
+}
+
+State *
+StateCtlUCommand::got_register(QRegister *reg) throw (Error)
+{
+	BEGIN_EXEC(&States::setqregstring);
+	register_argument = reg;
+	return &States::setqregstring;
+}
+
+State *
+StateSetQRegString::done(const gchar *str) throw (Error)
+{
+	BEGIN_EXEC(&States::start);
+
+	register_argument->undo_set_string();
+	register_argument->set_string(str);
+
+	return &States::start;
+}
+
+State *
+StateGetQRegString::got_register(QRegister *reg) throw (Error)
+{
+	gchar *str;
+
+	BEGIN_EXEC(&States::start);
+
+	str = reg->get_string();
+	if (*str) {
+		interface.ssm(SCI_BEGINUNDOACTION);
+		interface.ssm(SCI_ADDTEXT, strlen(str), (sptr_t)str);
+		interface.ssm(SCI_SCROLLCARET);
+		interface.ssm(SCI_ENDUNDOACTION);
+		ring.dirtify();
+
+		undo.push_msg(SCI_UNDO);
+	}
+	g_free(str);
+
+	return &States::start;
+}
+
+State *
+StateGetQRegInteger::got_register(QRegister *reg) throw (Error)
+{
+	BEGIN_EXEC(&States::start);
+
+	expressions.eval();
+	expressions.push(reg->get_integer());
+
+	return &States::start;
+}
+
+State *
+StateSetQRegInteger::got_register(QRegister *reg) throw (Error)
+{
+	BEGIN_EXEC(&States::start);
+
+	reg->undo_set_integer();
+	reg->set_integer(expressions.pop_num_calc());
+
+	return &States::start;
+}
+
+State *
+StateIncreaseQReg::got_register(QRegister *reg) throw (Error)
+{
+	gint64 res;
+
+	BEGIN_EXEC(&States::start);
+
+	reg->undo_set_integer();
+	res = reg->get_integer() + expressions.pop_num_calc();
+	expressions.push(reg->set_integer(res));
+
+	return &States::start;
+}
+
+State *
+StateMacro::got_register(QRegister *reg) throw (Error)
+{
+	BEGIN_EXEC(&States::start);
+
+	/* don't create new local Q-Registers if colon modifier is given */
+	reg->execute(!eval_colon());
+
+	return &States::start;
+}
+
+State *
+StateCopyToQReg::got_register(QRegister *reg) throw (Error)
+{
+	gint64 from, len;
+	Sci_TextRange tr;
+
+	BEGIN_EXEC(&States::start);
+	expressions.eval();
+
+	if (expressions.args() <= 1) {
+		from = interface.ssm(SCI_GETCURRENTPOS);
+		sptr_t line = interface.ssm(SCI_LINEFROMPOSITION, from) +
+			      expressions.pop_num_calc();
+
+		if (!Validate::line(line))
+			throw RangeError("X");
+
+		len = interface.ssm(SCI_POSITIONFROMLINE, line) - from;
+
+		if (len < 0) {
+			from += len;
+			len *= -1;
+		}
+	} else {
+		gint64 to = expressions.pop_num();
+		from = expressions.pop_num();
+
+		if (!Validate::pos(from) || !Validate::pos(to))
+			throw RangeError("X");
+
+		len = to - from;
+	}
+
+	tr.chrg.cpMin = from;
+	tr.chrg.cpMax = from + len;
+	tr.lpstrText = (char *)g_malloc(len + 1);
+	interface.ssm(SCI_GETTEXTRANGE, 0, (sptr_t)&tr);
+
+	if (eval_colon()) {
+		reg->undo_append_string();
+		reg->append_string(tr.lpstrText);
+	} else {
+		reg->undo_set_string();
+		reg->set_string(tr.lpstrText);
+	}
+	g_free(tr.lpstrText);
+
+	return &States::start;
+}
diff --git a/qbuffers.h b/qregisters.h
index d9c1b94..e810b7f 100644
--- a/qbuffers.h
+++ b/qregisters.h
@@ -1,12 +1,10 @@
-#ifndef __QBUFFERS_H
-#define __QBUFFERS_H
+#ifndef __QREGISTERS_H
+#define __QREGISTERS_H
 
-#include <string.h>
 #include <bsd/sys/queue.h>
 
 #include <glib.h>
 #include <glib/gprintf.h>
-#include <glib/gstdio.h>
 
 #include <Scintilla.h>
 
@@ -17,22 +15,6 @@
 #include "parser.h"
 
 /*
- * Auxiliary functions
- */
-static inline bool
-is_glob_pattern(const gchar *str)
-{
-	return strchr(str, '*') || strchr(str, '?');
-}
-
-/*
- * Get absolute/full version of a possibly relative path.
- * Works with existing and non-existing paths (in the latter case,
- * heuristics may be applied.)
- */
-gchar *get_absolute_path(const gchar *path);
-
-/*
  * Classes
  */
 
@@ -256,196 +238,10 @@ public:
 	bool pop(QRegister *reg);
 };
 
-class Buffer {
-	class UndoTokenClose : public UndoToken {
-		Buffer *buffer;
-
-	public:
-		UndoTokenClose(Buffer *_buffer)
-			      : UndoToken(), buffer(_buffer) {}
-
-		void run(void);
-	};
-
-public:
-	TAILQ_ENTRY(Buffer) buffers;
-
-	gchar *filename;
-	gint dot;
-
-	gint savepoint_id;
-
-	bool dirty;
-
-private:
-	typedef void document;
-	document *doc;
-
-public:
-	Buffer() : filename(NULL), dot(0), savepoint_id(0), dirty(false)
-	{
-		doc = (document *)interface.ssm(SCI_CREATEDOCUMENT);
-	}
-	~Buffer()
-	{
-		interface.ssm(SCI_RELEASEDOCUMENT, 0, (sptr_t)doc);
-		g_free(filename);
-	}
-
-	inline Buffer *&
-	next(void)
-	{
-		return TAILQ_NEXT(this, buffers);
-	}
-	inline Buffer *&
-	prev(void)
-	{
-		TAILQ_HEAD(Head, Buffer);
-
-		return TAILQ_PREV(this, Head, buffers);
-	}
-
-	inline void
-	set_filename(const gchar *filename)
-	{
-		gchar *resolved = get_absolute_path(filename);
-		g_free(Buffer::filename);
-		Buffer::filename = resolved;
-		interface.info_update(this);
-	}
-
-	inline void
-	edit(void)
-	{
-		interface.ssm(SCI_SETDOCPOINTER, 0, (sptr_t)doc);
-		interface.ssm(SCI_GOTOPOS, dot);
-		interface.info_update(this);
-	}
-	inline void
-	undo_edit(void)
-	{
-		interface.undo_info_update(this);
-		undo.push_msg(SCI_GOTOPOS, dot);
-		undo.push_msg(SCI_SETDOCPOINTER, 0, (sptr_t)doc);
-	}
-
-	bool load(const gchar *filename);
-
-	inline void
-	undo_close(void)
-	{
-		undo.push(new UndoTokenClose(this));
-	}
-};
-
-extern class Ring {
-	/*
-	 * Emitted after a buffer close
-	 * The pointer is the only remaining reference to the buffer!
-	 */
-	class UndoTokenEdit : public UndoToken {
-		Ring	*ring;
-		Buffer	*buffer;
-
-	public:
-		UndoTokenEdit(Ring *_ring, Buffer *_buffer)
-			     : UndoToken(), ring(_ring), buffer(_buffer) {}
-		~UndoTokenEdit()
-		{
-			if (buffer)
-				delete buffer;
-		}
-
-		void run(void);
-	};
-
-	class UndoTokenRemoveFile : public UndoToken {
-		gchar *filename;
-
-	public:
-		UndoTokenRemoveFile(const gchar *_filename)
-				   : filename(g_strdup(_filename)) {}
-		~UndoTokenRemoveFile()
-		{
-			g_free(filename);
-		}
-
-		void
-		run(void)
-		{
-			g_unlink(filename);
-		}
-	};
-
-	TAILQ_HEAD(Head, Buffer) head;
-
-public:
-	Buffer *current;
-
-	Ring() : current(NULL)
-	{
-		TAILQ_INIT(&head);
-	}
-	~Ring();
-
-	inline Buffer *
-	first(void)
-	{
-		return TAILQ_FIRST(&head);
-	}
-	inline Buffer *
-	last(void)
-	{
-		return TAILQ_LAST(&head, Head);
-	}
-
-	Buffer *find(const gchar *filename);
-	Buffer *find(gint64 id);
-
-	void dirtify(void);
-	bool is_any_dirty(void);
-
-	bool edit(gint64 id);
-	void edit(const gchar *filename);
-	inline void
-	undo_edit(void)
-	{
-		current->dot = interface.ssm(SCI_GETCURRENTPOS);
-		undo.push_var(current);
-		current->undo_edit();
-	}
-
-	bool save(const gchar *filename);
-
-	void close(Buffer *buffer);
-	void close(void);
-	inline void
-	undo_close(void)
-	{
-		current->undo_close();
-	}
-} ring;
-
 /*
  * Command states
  */
 
-class StateEditFile : public StateExpectString {
-private:
-	bool allowFilename;
-
-	void do_edit(const gchar *filename) throw (Error);
-	void do_edit(gint64 id) throw (Error);
-
-	void initial(void) throw (Error);
-	State *done(const gchar *str) throw (Error);
-};
-
-class StateSaveFile : public StateExpectString {
-private:
-	State *done(const gchar *str) throw (Error);
-};
-
 class StatePushQReg : public StateExpectQReg {
 private:
 	State *got_register(QRegister *reg) throw (Error);
@@ -509,9 +305,6 @@ private:
 };
 
 namespace States {
-	extern StateEditFile		editfile;
-	extern StateSaveFile		savefile;
-
 	extern StatePushQReg		pushqreg;
 	extern StatePopQReg		popqreg;
 	extern StateEQCommand		eqcommand;
@@ -529,6 +322,14 @@ namespace States {
 namespace QRegisters {
 	extern QRegisterTable	globals;
 	extern QRegisterTable	*locals;
+	extern QRegister	*current;
+
+	static inline void
+	undo_edit(void)
+	{
+		current->dot = interface.ssm(SCI_GETCURRENTPOS);
+		undo.push_var(current)->undo_edit();
+	}
 
 	enum Hook {
 		HOOK_ADD = 1,
diff --git a/qbuffers.cpp b/ring.cpp
index 8948f46..f1b051b 100644
--- a/qbuffers.cpp
+++ b/ring.cpp
@@ -14,8 +14,7 @@
 #include "undo.h"
 #include "parser.h"
 #include "expressions.h"
-#include "goto.h"
-#include "qbuffers.h"
+#include "ring.h"
 
 #ifdef G_OS_WIN32
 /* here it shouldn't cause conflicts with other headers */
@@ -28,342 +27,12 @@
 #endif
 
 namespace States {
-	StateEditFile		editfile;
-	StateSaveFile		savefile;
-
-	StatePushQReg		pushqreg;
-	StatePopQReg		popqreg;
-	StateEQCommand		eqcommand;
-	StateLoadQReg		loadqreg;
-	StateCtlUCommand	ctlucommand;
-	StateSetQRegString	setqregstring;
-	StateGetQRegString	getqregstring;
-	StateGetQRegInteger	getqreginteger;
-	StateSetQRegInteger	setqreginteger;
-	StateIncreaseQReg	increaseqreg;
-	StateMacro		macro;
-	StateCopyToQReg		copytoqreg;
+	StateEditFile	editfile;
+	StateSaveFile	savefile;
 }
 
-namespace QRegisters {
-	QRegisterTable		globals;
-	QRegisterTable		*locals = NULL;
-	static QRegister	*current = NULL;
-	static QRegisterStack	stack;
-
-	static inline void
-	undo_edit(void)
-	{
-		current->dot = interface.ssm(SCI_GETCURRENTPOS);
-		undo.push_var(current)->undo_edit();
-	}
-}
-
-static QRegister *register_argument = NULL;
-
 Ring ring;
 
-/* FIXME: clean up current_save_dot() usage */
-static inline void
-current_save_dot(void)
-{
-	gint dot = interface.ssm(SCI_GETCURRENTPOS);
-
-	if (ring.current)
-		ring.current->dot = dot;
-	else if (QRegisters::current)
-		QRegisters::current->dot = dot;
-}
-
-static inline void
-current_edit(void)
-{
-	if (ring.current)
-		ring.current->edit();
-	else if (QRegisters::current)
-		QRegisters::current->edit();
-}
-
-void
-QRegisterData::set_string(const gchar *str)
-{
-	edit();
-	dot = 0;
-
-	interface.ssm(SCI_BEGINUNDOACTION);
-	interface.ssm(SCI_SETTEXT, 0, (sptr_t)(str ? : ""));
-	interface.ssm(SCI_ENDUNDOACTION);
-
-	current_edit();
-}
-
-void
-QRegisterData::undo_set_string(void)
-{
-	/* set_string() assumes that dot has been saved */
-	current_save_dot();
-
-	if (!must_undo)
-		return;
-
-	if (ring.current)
-		ring.current->undo_edit();
-	else if (QRegisters::current)
-		QRegisters::current->undo_edit();
-
-	undo.push_var<gint>(dot);
-	undo.push_msg(SCI_UNDO);
-
-	undo_edit();
-}
-
-void
-QRegisterData::append_string(const gchar *str)
-{
-	if (!str)
-		return;
-
-	edit();
-
-	interface.ssm(SCI_BEGINUNDOACTION);
-	interface.ssm(SCI_APPENDTEXT, strlen(str), (sptr_t)str);
-	interface.ssm(SCI_ENDUNDOACTION);
-
-	current_edit();
-}
-
-gchar *
-QRegisterData::get_string(void)
-{
-	gint size;
-	gchar *str;
-
-	current_save_dot();
-	edit();
-
-	size = interface.ssm(SCI_GETLENGTH) + 1;
-	str = (gchar *)g_malloc(size);
-	interface.ssm(SCI_GETTEXT, size, (sptr_t)str);
-
-	current_edit();
-
-	return str;
-}
-
-void
-QRegisterData::edit(void)
-{
-	interface.ssm(SCI_SETDOCPOINTER, 0, (sptr_t)get_document());
-	interface.ssm(SCI_GOTOPOS, dot);
-}
-
-void
-QRegisterData::undo_edit(void)
-{
-	if (!must_undo)
-		return;
-
-	undo.push_msg(SCI_GOTOPOS, dot);
-	undo.push_msg(SCI_SETDOCPOINTER, 0, (sptr_t)get_document());
-}
-
-void
-QRegister::edit(void)
-{
-	QRegisterData::edit();
-	interface.info_update(this);
-}
-
-void
-QRegister::undo_edit(void)
-{
-	if (!must_undo)
-		return;
-
-	interface.undo_info_update(this);
-	QRegisterData::undo_edit();
-}
-
-void
-QRegister::execute(bool locals) throw (State::Error)
-{
-	gchar *str = get_string();
-
-	try {
-		Execute::macro(str, locals);
-	} catch (...) {
-		g_free(str);
-		throw; /* forward */
-	}
-
-	g_free(str);
-}
-
-bool
-QRegister::load(const gchar *filename)
-{
-	gchar *contents;
-	gsize size;
-
-	/* FIXME: prevent excessive allocations by reading file into buffer */
-	if (!g_file_get_contents(filename, &contents, &size, NULL))
-		return false;
-
-	edit();
-	dot = 0;
-
-	interface.ssm(SCI_BEGINUNDOACTION);
-	interface.ssm(SCI_CLEARALL);
-	interface.ssm(SCI_APPENDTEXT, size, (sptr_t)contents);
-	interface.ssm(SCI_ENDUNDOACTION);
-
-	g_free(contents);
-
-	current_edit();
-
-	return true;
-}
-
-gint64
-QRegisterBufferInfo::get_integer(void)
-{
-	gint64 id = 1;
-
-	if (!ring.current)
-		return 0;
-
-	for (Buffer *buffer = ring.first();
-	     buffer != ring.current;
-	     buffer = buffer->next())
-		id++;
-
-	return id;
-}
-
-gchar *
-QRegisterBufferInfo::get_string(void)
-{
-	gchar *filename = ring.current ? ring.current->filename : NULL;
-
-	return g_strdup(filename ? : "");
-}
-
-void
-QRegisterBufferInfo::edit(void)
-{
-	gchar *filename = ring.current ? ring.current->filename : NULL;
-
-	QRegister::edit();
-
-	interface.ssm(SCI_BEGINUNDOACTION);
-	interface.ssm(SCI_SETTEXT, 0, (sptr_t)(filename ? : ""));
-	interface.ssm(SCI_ENDUNDOACTION);
-
-	undo.push_msg(SCI_UNDO);
-}
-
-void
-QRegisterTable::initialize(void)
-{
-	/* general purpose registers */
-	for (gchar q = 'A'; q <= 'Z'; q++)
-		initialize(q);
-	for (gchar q = '0'; q <= '9'; q++)
-		initialize(q);
-}
-
-void
-QRegisterTable::edit(QRegister *reg)
-{
-	current_save_dot();
-	reg->edit();
-
-	ring.current = NULL;
-	QRegisters::current = reg;
-}
-
-void
-QRegisterStack::UndoTokenPush::run(void)
-{
-	SLIST_INSERT_HEAD(&stack->head, entry, entries);
-	entry = NULL;
-}
-
-void
-QRegisterStack::UndoTokenPop::run(void)
-{
-	Entry *entry = SLIST_FIRST(&stack->head);
-
-	SLIST_REMOVE_HEAD(&stack->head, entries);
-	delete entry;
-}
-
-void
-QRegisterStack::push(QRegister *reg)
-{
-	Entry *entry = new Entry();
-
-	entry->set_integer(reg->get_integer());
-	if (reg->string) {
-		gchar *str = reg->get_string();
-		entry->set_string(str);
-		g_free(str);
-	}
-	entry->dot = reg->dot;
-
-	SLIST_INSERT_HEAD(&head, entry, entries);
-	undo.push(new UndoTokenPop(this));
-}
-
-bool
-QRegisterStack::pop(QRegister *reg)
-{
-	Entry *entry = SLIST_FIRST(&head);
-	QRegisterData::document *string;
-
-	if (!entry)
-		return false;
-
-	reg->undo_set_integer();
-	reg->set_integer(entry->get_integer());
-
-	/* exchange document ownership between Stack entry and Q-Register */
-	string = reg->string;
-	if (reg->must_undo)
-		undo.push_var(reg->string);
-	reg->string = entry->string;
-	undo.push_var(entry->string);
-	entry->string = string;
-
-	if (reg->must_undo)
-		undo.push_var(reg->dot);
-	reg->dot = entry->dot;
-
-	SLIST_REMOVE_HEAD(&head, entries);
-	/* pass entry ownership to undo stack */
-	undo.push(new UndoTokenPush(this, entry));
-
-	return true;
-}
-
-QRegisterStack::~QRegisterStack()
-{
-	Entry *entry, *next;
-
-	SLIST_FOREACH_SAFE(entry, &head, entries, next)
-		delete entry;
-}
-
-void
-QRegisters::hook(Hook type)
-{
-	if (!(Flags::ed & Flags::ED_HOOKS))
-		return;
-
-	expressions.push(type);
-	globals["0"]->execute();
-}
-
 void
 Buffer::UndoTokenClose::run(void)
 {
@@ -639,6 +308,7 @@ Ring::save(const gchar *filename)
 			undo.push(new UndoTokenRemoveFile(filename));
 	}
 
+	/* FIXME: improve by writing before and after document gap */
 	buffer = (const gchar *)interface.ssm(SCI_GETCHARACTERPOINTER);
 	size = interface.ssm(SCI_GETLENGTH);
 
@@ -867,191 +537,3 @@ StateSaveFile::done(const gchar *str) throw (Error)
 
 	return &States::start;
 }
-
-State *
-StatePushQReg::got_register(QRegister *reg) throw (Error)
-{
-	BEGIN_EXEC(&States::start);
-
-	QRegisters::stack.push(reg);
-
-	return &States::start;
-}
-
-State *
-StatePopQReg::got_register(QRegister *reg) throw (Error)
-{
-	BEGIN_EXEC(&States::start);
-
-	if (!QRegisters::stack.pop(reg))
-		throw Error("Q-Register stack is empty");
-
-	return &States::start;
-}
-
-State *
-StateEQCommand::got_register(QRegister *reg) throw (Error)
-{
-	BEGIN_EXEC(&States::loadqreg);
-	register_argument = reg;
-	return &States::loadqreg;
-}
-
-State *
-StateLoadQReg::done(const gchar *str) throw (Error)
-{
-	BEGIN_EXEC(&States::start);
-
-	if (*str) {
-		register_argument->undo_load();
-		if (!register_argument->load(str))
-			throw Error("Cannot load \"%s\" into Q-Register \"%s\"",
-				    str, register_argument->name);
-	} else {
-		if (ring.current)
-			ring.undo_edit();
-		else /* QRegisters::current != NULL */
-			QRegisters::undo_edit();
-		QRegisters::globals.edit(register_argument);
-	}
-
-	return &States::start;
-}
-
-State *
-StateCtlUCommand::got_register(QRegister *reg) throw (Error)
-{
-	BEGIN_EXEC(&States::setqregstring);
-	register_argument = reg;
-	return &States::setqregstring;
-}
-
-State *
-StateSetQRegString::done(const gchar *str) throw (Error)
-{
-	BEGIN_EXEC(&States::start);
-
-	register_argument->undo_set_string();
-	register_argument->set_string(str);
-
-	return &States::start;
-}
-
-State *
-StateGetQRegString::got_register(QRegister *reg) throw (Error)
-{
-	gchar *str;
-
-	BEGIN_EXEC(&States::start);
-
-	str = reg->get_string();
-	if (*str) {
-		interface.ssm(SCI_BEGINUNDOACTION);
-		interface.ssm(SCI_ADDTEXT, strlen(str), (sptr_t)str);
-		interface.ssm(SCI_SCROLLCARET);
-		interface.ssm(SCI_ENDUNDOACTION);
-		ring.dirtify();
-
-		undo.push_msg(SCI_UNDO);
-	}
-	g_free(str);
-
-	return &States::start;
-}
-
-State *
-StateGetQRegInteger::got_register(QRegister *reg) throw (Error)
-{
-	BEGIN_EXEC(&States::start);
-
-	expressions.eval();
-	expressions.push(reg->get_integer());
-
-	return &States::start;
-}
-
-State *
-StateSetQRegInteger::got_register(QRegister *reg) throw (Error)
-{
-	BEGIN_EXEC(&States::start);
-
-	reg->undo_set_integer();
-	reg->set_integer(expressions.pop_num_calc());
-
-	return &States::start;
-}
-
-State *
-StateIncreaseQReg::got_register(QRegister *reg) throw (Error)
-{
-	gint64 res;
-
-	BEGIN_EXEC(&States::start);
-
-	reg->undo_set_integer();
-	res = reg->get_integer() + expressions.pop_num_calc();
-	expressions.push(reg->set_integer(res));
-
-	return &States::start;
-}
-
-State *
-StateMacro::got_register(QRegister *reg) throw (Error)
-{
-	BEGIN_EXEC(&States::start);
-
-	/* don't create new local Q-Registers if colon modifier is given */
-	reg->execute(!eval_colon());
-
-	return &States::start;
-}
-
-State *
-StateCopyToQReg::got_register(QRegister *reg) throw (Error)
-{
-	gint64 from, len;
-	Sci_TextRange tr;
-
-	BEGIN_EXEC(&States::start);
-	expressions.eval();
-
-	if (expressions.args() <= 1) {
-		from = interface.ssm(SCI_GETCURRENTPOS);
-		sptr_t line = interface.ssm(SCI_LINEFROMPOSITION, from) +
-			      expressions.pop_num_calc();
-
-		if (!Validate::line(line))
-			throw RangeError("X");
-
-		len = interface.ssm(SCI_POSITIONFROMLINE, line) - from;
-
-		if (len < 0) {
-			from += len;
-			len *= -1;
-		}
-	} else {
-		gint64 to = expressions.pop_num();
-		from = expressions.pop_num();
-
-		if (!Validate::pos(from) || !Validate::pos(to))
-			throw RangeError("X");
-
-		len = to - from;
-	}
-
-	tr.chrg.cpMin = from;
-	tr.chrg.cpMax = from + len;
-	tr.lpstrText = (char *)g_malloc(len + 1);
-	interface.ssm(SCI_GETTEXTRANGE, 0, (sptr_t)&tr);
-
-	if (eval_colon()) {
-		reg->undo_append_string();
-		reg->append_string(tr.lpstrText);
-	} else {
-		reg->undo_set_string();
-		reg->set_string(tr.lpstrText);
-	}
-	g_free(tr.lpstrText);
-
-	return &States::start;
-}
diff --git a/ring.h b/ring.h
new file mode 100644
index 0000000..da4f322
--- /dev/null
+++ b/ring.h
@@ -0,0 +1,246 @@
+#ifndef __RING_H
+#define __RING_H
+
+#include <string.h>
+#include <bsd/sys/queue.h>
+
+#include <glib.h>
+#include <glib/gprintf.h>
+#include <glib/gstdio.h>
+
+#include <Scintilla.h>
+
+#include "sciteco.h"
+#include "interface.h"
+#include "undo.h"
+#include "qregisters.h"
+#include "parser.h"
+
+/*
+ * Auxiliary functions
+ */
+static inline bool
+is_glob_pattern(const gchar *str)
+{
+	return strchr(str, '*') || strchr(str, '?');
+}
+
+/*
+ * Get absolute/full version of a possibly relative path.
+ * Works with existing and non-existing paths (in the latter case,
+ * heuristics may be applied.)
+ */
+gchar *get_absolute_path(const gchar *path);
+
+/*
+ * Classes
+ */
+
+class Buffer {
+	class UndoTokenClose : public UndoToken {
+		Buffer *buffer;
+
+	public:
+		UndoTokenClose(Buffer *_buffer)
+			      : UndoToken(), buffer(_buffer) {}
+
+		void run(void);
+	};
+
+public:
+	TAILQ_ENTRY(Buffer) buffers;
+
+	gchar *filename;
+	gint dot;
+
+	gint savepoint_id;
+
+	bool dirty;
+
+private:
+	typedef void document;
+	document *doc;
+
+public:
+	Buffer() : filename(NULL), dot(0), savepoint_id(0), dirty(false)
+	{
+		doc = (document *)interface.ssm(SCI_CREATEDOCUMENT);
+	}
+	~Buffer()
+	{
+		interface.ssm(SCI_RELEASEDOCUMENT, 0, (sptr_t)doc);
+		g_free(filename);
+	}
+
+	inline Buffer *&
+	next(void)
+	{
+		return TAILQ_NEXT(this, buffers);
+	}
+	inline Buffer *&
+	prev(void)
+	{
+		TAILQ_HEAD(Head, Buffer);
+
+		return TAILQ_PREV(this, Head, buffers);
+	}
+
+	inline void
+	set_filename(const gchar *filename)
+	{
+		gchar *resolved = get_absolute_path(filename);
+		g_free(Buffer::filename);
+		Buffer::filename = resolved;
+		interface.info_update(this);
+	}
+
+	inline void
+	edit(void)
+	{
+		interface.ssm(SCI_SETDOCPOINTER, 0, (sptr_t)doc);
+		interface.ssm(SCI_GOTOPOS, dot);
+		interface.info_update(this);
+	}
+	inline void
+	undo_edit(void)
+	{
+		interface.undo_info_update(this);
+		undo.push_msg(SCI_GOTOPOS, dot);
+		undo.push_msg(SCI_SETDOCPOINTER, 0, (sptr_t)doc);
+	}
+
+	bool load(const gchar *filename);
+
+	inline void
+	undo_close(void)
+	{
+		undo.push(new UndoTokenClose(this));
+	}
+};
+
+extern class Ring {
+	/*
+	 * Emitted after a buffer close
+	 * The pointer is the only remaining reference to the buffer!
+	 */
+	class UndoTokenEdit : public UndoToken {
+		Ring	*ring;
+		Buffer	*buffer;
+
+	public:
+		UndoTokenEdit(Ring *_ring, Buffer *_buffer)
+			     : UndoToken(), ring(_ring), buffer(_buffer) {}
+		~UndoTokenEdit()
+		{
+			if (buffer)
+				delete buffer;
+		}
+
+		void run(void);
+	};
+
+	class UndoTokenRemoveFile : public UndoToken {
+		gchar *filename;
+
+	public:
+		UndoTokenRemoveFile(const gchar *_filename)
+				   : filename(g_strdup(_filename)) {}
+		~UndoTokenRemoveFile()
+		{
+			g_free(filename);
+		}
+
+		void
+		run(void)
+		{
+			g_unlink(filename);
+		}
+	};
+
+	TAILQ_HEAD(Head, Buffer) head;
+
+public:
+	Buffer *current;
+
+	Ring() : current(NULL)
+	{
+		TAILQ_INIT(&head);
+	}
+	~Ring();
+
+	inline Buffer *
+	first(void)
+	{
+		return TAILQ_FIRST(&head);
+	}
+	inline Buffer *
+	last(void)
+	{
+		return TAILQ_LAST(&head, Head);
+	}
+
+	Buffer *find(const gchar *filename);
+	Buffer *find(gint64 id);
+
+	void dirtify(void);
+	bool is_any_dirty(void);
+
+	bool edit(gint64 id);
+	void edit(const gchar *filename);
+	inline void
+	undo_edit(void)
+	{
+		current->dot = interface.ssm(SCI_GETCURRENTPOS);
+		undo.push_var(current);
+		current->undo_edit();
+	}
+
+	bool save(const gchar *filename);
+
+	void close(Buffer *buffer);
+	void close(void);
+	inline void
+	undo_close(void)
+	{
+		current->undo_close();
+	}
+} ring;
+
+/*
+ * Command states
+ */
+
+class StateEditFile : public StateExpectString {
+private:
+	bool allowFilename;
+
+	void do_edit(const gchar *filename) throw (Error);
+	void do_edit(gint64 id) throw (Error);
+
+	void initial(void) throw (Error);
+	State *done(const gchar *str) throw (Error);
+};
+
+class StateSaveFile : public StateExpectString {
+private:
+	State *done(const gchar *str) throw (Error);
+};
+
+namespace States {
+	extern StateEditFile	editfile;
+	extern StateSaveFile	savefile;
+}
+
+/* FIXME: clean up current_save_dot() usage */
+static inline void
+current_save_dot(void)
+{
+	gint dot = interface.ssm(SCI_GETCURRENTPOS);
+
+	if (ring.current)
+		ring.current->dot = dot;
+	else if (QRegisters::current)
+		QRegisters::current->dot = dot;
+}
+
+#endif
diff --git a/search.cpp b/search.cpp
index f27e744..701f36c 100644
--- a/search.cpp
+++ b/search.cpp
@@ -6,7 +6,8 @@
 #include "sciteco.h"
 #include "expressions.h"
 #include "undo.h"
-#include "qbuffers.h"
+#include "qregisters.h"
+#include "ring.h"
 #include "parser.h"
 #include "search.h"
 
diff --git a/search.h b/search.h
index 12b95db..2bddedd 100644
--- a/search.h
+++ b/search.h
@@ -5,7 +5,7 @@
 
 #include "sciteco.h"
 #include "parser.h"
-#include "qbuffers.h"
+#include "ring.h"
 
 /*
  * "S" command state and base class for all other search/replace commands