full split complete

+ editor removes per-buffer fields.
+ switching from internal use of 'int' to 'size_t'.
+ deleting old code
+ double checking relevancy of comments. A lot has changed in
  5 years, even more so in the past week.
+ fixing a few vestigal memory errors from the overhaul.
+ fixing search behavior

CMakeLists.txt

@@ -2,9 +2,9 @@ cmake_minimum_required(VERSION 3.15)
 project(ke C)  # Specify C language explicitly
 
 set(CMAKE_C_STANDARD 99)
-set(KE_VERSION "2.0.1")
+set(KE_VERSION "2.1.1")
 
-set(CMAKE_C_FLAGS "-Wall -Wextra -pedantic -Wshadow -Werror -std=c99 -g -Werror=stringop-truncation")
+set(CMAKE_C_FLAGS "-Wall -Wextra -pedantic -Wshadow -Werror -std=c99 -g")
 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -D_DEFAULT_SOURCE -D_XOPEN_SOURCE")
 
 # Optionally enable AddressSanitizer (ASan)
@@ -19,16 +19,34 @@ endif()
 
 include(GNUInstallDirs)
 
-# Add executable
-add_executable(ke
+set(SOURCES
         abuf.c
+        core.c
         term.c
         buffer.c
         editor.c
-        core.c
-        core.h
+        editing.c
+        killring.c
+        process.c
+        undo.c
         main.c
 )
+
+set(HEADERS
+        abuf.h
+        core.h
+        term.h
+        buffer.h
+        editor.h
+        editing.h
+        killring.h
+        process.h
+        undo.h
+)
+
+
+# Add executable
+add_executable(ke ${SOURCES} ${HEADERS})
 target_compile_definitions(ke PRIVATE KE_VERSION="ke version ${KE_VERSION}")
 install(TARGETS ke RUNTIME DESTINATION bin)
 install(FILES ke.1 TYPE MAN)

Makefile

@@ -11,8 +11,10 @@ LDFLAGS :=	-fsanitize=address
 
 all: $(TARGET) test.txt
 
-SRCS := main.c abuf.c term.c buffer.c editor.c core.c
-HDRS :=        abuf.h term.h buffer.h editor.h core.h
+SRCS := main.c abuf.c core.c term.c buffer.c editor.c editing.c killring.c \
+	       process.c undo.c
+HDRS :=        abuf.h core.h term.h buffer.h editor.h editing.c killring.h \
+	       process.h undo.h
 
 $(TARGET): $(SRCS)
 	$(CC) $(CFLAGS) -o $(TARGET) $(SRCS) $(LDFLAGS)

abuf.c

@@ -28,19 +28,24 @@ ab_init(abuf *buf)
 void
 ab_init_cap(abuf *buf, const size_t cap)
 {
-	buf->b    = calloc(cap, 1);
-	buf->size = 0;
-	buf->cap  = cap;
+	ab_init(buf);
+
+	if (cap > 0) {
+		ab_resize(buf, cap);
+	}
 }
 
 
 void
 ab_resize(abuf *buf, size_t cap)
 {
-	cap = cap_growth(buf->cap, cap);
-	buf->b = realloc(buf->b, cap);
-	assert(buf->b != NULL);
+	char	*newbuf = NULL;
+
+	cap = cap_growth(buf->cap, cap) + 1;
+	newbuf = realloc(buf->b, cap);
+	assert(newbuf != NULL);
 	buf->cap = cap;
+	buf->b   = newbuf;
 }
 
 
@@ -66,6 +71,18 @@ ab_append(abuf *buf, const char *s, size_t len)
 }
 
 
+void
+ab_append_ab(abuf *buf, const abuf *other)
+{
+	assert(buf != NULL);
+	if (other == NULL) {
+		return;
+	}
+
+	ab_append(buf, other->b, other->size);
+}
+
+
 void
 ab_prependch(abuf *buf, const char c)
 {
@@ -92,6 +109,18 @@ ab_prepend(abuf *buf, const char *s, const size_t len)
 }
 
 
+void
+ab_prepend_ab(abuf *buf, const abuf *other)
+{
+	assert(buf != NULL);
+	if (other == NULL) {
+		return;
+	}
+
+	ab_prepend(buf, other->b, other->size);
+}
+
+
 void
 ab_free(abuf *buf)
 {

abuf.h

@@ -1,8 +1,8 @@
 /*
  * abuf.h - append/prepend buffer utilities
  */
-#ifndef ABUF_H
-#define ABUF_H
+#ifndef KE_ABUF_H
+#define KE_ABUF_H
 
 #include <stddef.h>
 
@@ -22,8 +22,10 @@ void		 ab_init_cap(abuf *buf, size_t cap);
 void		 ab_resize(abuf *buf, size_t cap);
 void		 ab_appendch(abuf *buf, char c);
 void		 ab_append(abuf *buf, const char *s, size_t len);
+void		 ab_append_ab(abuf *buf, const abuf *other);
 void		 ab_prependch(abuf *buf, const char c);
 void		 ab_prepend(abuf *buf, const char *s, const size_t len);
+void		 ab_prepend_ab(abuf *buf, const abuf *other);
 void		 ab_free(abuf *buf);
 
 

buffer.c

@@ -35,12 +35,13 @@ static int
 buffer_find_exact_by_name(const char *name)
 {
 	buffer	*b = NULL;
+	size_t   i = 0;
 
 	if (name == NULL) {
 		return -1;
 	}
 
-	for (int i = 0; i < editor.bufcount; i++) {
+	for (i = 0; i < editor.bufcount; i++) {
 		b                = editor.buffers[i];
 		const char *full = b->filename;
 		const char *base = buf_basename(full);
@@ -66,11 +67,12 @@ static int
 buffer_collect_prefix_matches(const char *prefix, int *out_idx, const int max_out)
 {
 	buffer	*b       = NULL;
-	int	 count   = 0;
-	int	 matched = 0;
+	int      count   = 0;
+	int      matched = 0;
+	size_t   i       = 0;
 	size_t	 plen    = (prefix ? strlen(prefix) : 0);
 
-	for (int i = 0; i < editor.bufcount; i++) {
+	for (i = 0; i < editor.bufcount; i++) {
 		matched = 0;
 		b = editor.buffers[i];
 
@@ -206,49 +208,6 @@ buffer_switch_prompt_cb(char *buf, const int16_t key)
 }
 
 
-static void
-buffer_bind_to_editor(const buffer *b)
-{
-	if (b == NULL) {
-		return;
-	}
-
-	editor.curx      = b->curx;
-	editor.cury      = b->cury;
-	editor.rx        = b->rx;
-	editor.nrows     = b->nrows;
-	editor.rowoffs   = b->rowoffs;
-	editor.coloffs   = b->coloffs;
-	editor.row       = b->row;
-	editor.filename  = b->filename;
-	editor.dirty     = b->dirty;
-	editor.mark_set  = b->mark_set;
-	editor.mark_curx = b->mark_curx;
-	editor.mark_cury = b->mark_cury;
-}
-
-
-static void
-buffer_extract_from_editor(buffer *b)
-{
-	if (b == NULL) {
-		return;
-	}
-
-	b->curx      = editor.curx;
-	b->cury      = editor.cury;
-	b->rx        = editor.rx;
-	b->nrows     = editor.nrows;
-	b->rowoffs   = editor.rowoffs;
-	b->coloffs   = editor.coloffs;
-	b->row       = editor.row;
-	b->filename  = editor.filename;
-	b->dirty     = editor.dirty;
-	b->mark_set  = editor.mark_set;
-	b->mark_curx = editor.mark_curx;
-	b->mark_cury = editor.mark_cury;
-}
-
 const char *
 buffer_name(buffer *b)
 {
@@ -267,7 +226,7 @@ buffers_init(void)
 
 	editor.buffers  = NULL;
 	editor.bufcount = 0;
-	editor.curbuf   = -1;
+	editor.curbuf   = 0;
 	editor.bufcap	= 0;
 
 	idx = buffer_add_empty();
@@ -280,8 +239,9 @@ buffer_list_resize(void)
 {
 	buffer	**newlist = NULL;
 
-	if (editor.bufcount == (int)editor.bufcap) {
-		editor.bufcap = cap_growth((int)editor.bufcap, editor.bufcount + 1);
+	if (editor.bufcount == editor.bufcap) {
+		editor.bufcap = (size_t)cap_growth((int)editor.bufcap,
+			(int)editor.bufcount + 1);
 
 		newlist = realloc(editor.buffers, sizeof(buffer *) * editor.bufcap);
 		assert(newlist != NULL);
@@ -314,33 +274,22 @@ buffer_add_empty(void)
 	buf->mark_curx = 0;
 	buf->mark_cury = 0;
 
+	undo_tree_init(&buf->undo);
+
 	editor.buffers[editor.bufcount] = buf;
-	idx                             = editor.bufcount;
+	idx                             = (int)editor.bufcount;
 	editor.bufcount++;
 	return idx;
 }
 
 
-void
-buffer_save_current(void)
-{
-	buffer	*b = NULL;
-
-	if (editor.curbuf < 0 || editor.curbuf >= editor.bufcount) {
-		return;
-	}
-
-	b = editor.buffers[editor.curbuf];
-	buffer_extract_from_editor(b);
-}
-
-
 buffer *
 buffer_current(void)
 {
-	if (editor.curbuf < 0 || editor.curbuf >= editor.bufcount) {
+	if (editor.bufcount == 0 || editor.curbuf >= editor.bufcount) {
 		return NULL;
 	}
+
 	return editor.buffers[editor.curbuf];
 }
 
@@ -377,21 +326,16 @@ buffer_switch(const int idx)
 {
 	buffer	*b = NULL;
 
-	if (idx < 0 || idx >= editor.bufcount) {
+	if (idx < 0 || (size_t)idx >= editor.bufcount) {
 		return;
 	}
 
-	if (editor.curbuf == idx) {
+	if (editor.curbuf == (size_t)idx) {
 		return;
 	}
 
-	if (editor.curbuf >= 0) {
-		buffer_save_current();
-	}
-
 	b = editor.buffers[idx];
-	buffer_bind_to_editor(b);
-	editor.curbuf  = idx;
+	editor.curbuf  = (size_t)idx;
 	editor.dirtyex = 1;
 	editor_set_status("Switched to buffer %d: %s", editor.curbuf, buffer_name(b));
 }
@@ -400,28 +344,28 @@ buffer_switch(const int idx)
 void
 buffer_next(void)
 {
-	int idx = 0;
-
+	size_t idx = 0;
+	
 	if (editor.bufcount <= 1) {
 		return;
 	}
-
+	
 	idx = (editor.curbuf + 1) % editor.bufcount;
-	buffer_switch(idx);
+	buffer_switch((int)idx);
 }
 
 
 void
 buffer_prev(void)
 {
-	int	 idx = 0;
-
+	size_t	 idx = 0;
+	
 	if (editor.bufcount <= 1) {
 		return;
 	}
-
-	idx = (editor.curbuf - 1 + editor.bufcount) % editor.bufcount;
-	buffer_switch(idx);
+	
+	idx = (editor.curbuf == 0) ? (editor.bufcount - 1) : (editor.curbuf - 1);
+	buffer_switch((int)idx);
 }
 
 
@@ -429,21 +373,20 @@ void
 buffer_close_current(void)
 {
 	buffer	*b   = NULL;
-	int	 closing = 0;
+	size_t	 closing = 0;
 	int	 target  = 0;
 	int	 nb      = 0;
 
 	/* sanity check */
-	if (editor.curbuf < 0 || editor.curbuf >= editor.bufcount) {
+	if (editor.bufcount == 0 || editor.curbuf >= editor.bufcount) {
 		editor_set_status("No buffer to close.");
 		return;
 	}
 
 	closing = editor.curbuf;
 
-	target = -1;
 	if (editor.bufcount > 1) {
-		target = (closing - 1 >= 0) ? (closing - 1) : (closing + 1);
+		target = (closing > 0) ? (int) (closing - 1) : (int) (closing + 1);
 		buffer_switch(target);
 	} else {
 		nb = buffer_add_empty();
@@ -453,7 +396,7 @@ buffer_close_current(void)
 	b = editor.buffers[closing];
 	if (b) {
 		if (b->row) {
-			for (int i = 0; i < b->nrows; i++) {
+			for (size_t i = 0; i < b->nrows; i++) {
 				ab_free(&b->row[i]);
 			}
 			free(b->row);
@@ -466,11 +409,11 @@ buffer_close_current(void)
 	}
 
 	memmove(&editor.buffers[closing], &editor.buffers[closing + 1],
-	        sizeof(buffer *) * (editor.bufcount - closing - 1));
+		sizeof(buffer *) * (editor.bufcount - closing - 1));
 
 	editor.bufcount--;
 	if (editor.bufcount == 0) {
-		editor.curbuf = -1;
+		editor.curbuf = 0;
 	} else {
 		if (editor.curbuf > closing) {
 			editor.curbuf--;
@@ -479,7 +422,7 @@ buffer_close_current(void)
 
 	editor.dirtyex = 1;
 	editor_set_status("Closed buffer. Now on %s",
-	                  buffer_name(editor.buffers[editor.curbuf]));
+			  buffer_name(editor.buffers[editor.curbuf]));
 }
 
 
@@ -512,8 +455,9 @@ buffer_switch_by_name(void)
 	if (idx >= 0) {
 		buffer_switch(idx);
 	} else {
-		editor_set_status("No such buffer: %s", name);
+		editor_set_status("No open buffer: %s", name);
 	}
 
 	free(name);
 }
+

buffer.h

@@ -1,24 +1,25 @@
-#ifndef BUFFER_H
-#define BUFFER_H
+#ifndef KE_BUFFER_H
+#define KE_BUFFER_H
 
 #include "abuf.h"
+#include "undo.h"
 
 
 typedef struct buffer {
-	int	 curx, cury;
-	int	 rx;
-	int	 nrows;
-	int	 rowoffs, coloffs;
-	abuf	*row;
-	char	*filename;
-	int	 dirty;
-	int	 mark_set;
-	int	 mark_curx, mark_cury;
+	size_t		 curx, cury;
+	size_t		 rx;
+	size_t		 nrows;
+	size_t		 rowoffs, coloffs;
+	abuf		*row;
+	char		*filename;
+	int		 dirty;
+	int		 mark_set;
+	size_t		 mark_curx, mark_cury;
+	undo_tree	 undo;
 } buffer;
 
-/* Access current buffer and convenient aliases for file-specific fields */
-buffer		*buffer_current(void);
 
+buffer				*buffer_current(void);
 #define CURBUF			(buffer_current())
 #define EROW			(CURBUF->row)
 #define ENROWS			(CURBUF->nrows)

core.c

@@ -1,3 +1,4 @@
+#include <sys/stat.h>
 #include <assert.h>
 #include <stddef.h>
 #include <stdio.h>
@@ -7,7 +8,9 @@
 
 #include "core.h"
 
+
 #ifdef	INCLUDE_STRNSTR
+
 /*
  * Find the first occurrence of find in s, where the search is limited to the
  * first slen characters of s.
@@ -35,19 +38,42 @@ strnstr(const char *s, const char *find, size_t slen)
 #endif
 
 
-char
-nibble_to_hex(char c)
+int
+path_is_dir(const char *path)
 {
-	c &= 0xf;
-	if (c < 10) {
-		return (char)('0' + c);
+	struct stat st;
+
+	if (path == NULL) {
+		return 0;
 	}
-	return (char)('A' + (c - 10));
+
+	if (stat(path, &st) == 0) {
+		return S_ISDIR(st.st_mode);
+	}
+
+	return 0;
+}
+
+
+size_t
+str_lcp2(const char *a, const char *b)
+{
+	size_t	 i = 0;
+
+	if (!a || !b) {
+		return 0;
+	}
+
+	while (a[i] && b[i] && a[i] == b[i]) {
+		i++;
+	}
+
+	return i;
 }
 
 
 void
-swap_int(int *first, int *second)
+swap_size_t(size_t *first, size_t *second)
 {
 	*first ^= *second;
 	*second ^= *first;
@@ -122,3 +148,4 @@ die(const char* s)
 	perror(s);
 	exit(1);
 }
+

core.h

@@ -4,8 +4,18 @@
 #include <stddef.h>
 
 
-#define		calloc1(sz)		calloc(1, sz)
-#define		INITIAL_CAPACITY	8
+#ifndef KE_VERSION
+#define KE_VERSION		"ke dev build"
+#endif
+
+
+#define ESCSEQ			"\x1b["
+#define	CTRL_KEY(key)		((key)&0x1f)
+#define TAB_STOP		8
+#define MSG_TIMEO		3
+
+#define	TAB_STOP		8
+#define	INITIAL_CAPACITY	8
 
 
 typedef enum key_press {
@@ -29,13 +39,14 @@ char	*strnstr(const char *s, const char *find, size_t slen);
 #define	INCLUDE_STRNSTR
 #endif
 
-char		 nibble_to_hex(char c);
-void		 swap_int(int *first, int *second);
-int		 next_power_of_2(int n);
-int		 cap_growth(int cap, int sz);
+int		 path_is_dir(const char *path);
+size_t		 str_lcp2(const char *a, const char *b);
+void		 swap_size_t(size_t *first, size_t *second);
+int 		 next_power_of_2(int n);
+int 		 cap_growth(int cap, int sz);
 size_t		 kstrnlen(const char *buf, size_t max);
 void		 kwrite(int fd, const char *buf, int len);
 void		 die(const char *s);
 
 
-#endif
+#endif

editing.h

@@ -0,0 +1,50 @@
+#ifndef KE_EDITING_H
+#define KE_EDITING_H
+
+#include <stdint.h>
+
+#include "abuf.h"
+
+
+/* miscellaneous */
+void		 file_open_prompt_cb(char *buf, int16_t key);
+int		 erow_render_to_cursor(const abuf *row, int cx);
+int		 erow_cursor_to_render(abuf *row, int rx);
+int		 erow_init(abuf *row, int len);
+void		 erow_insert(int at, char *s, int len);
+void		 jump_to_position(size_t col, size_t row);
+void		 goto_line(void);
+int	    	 cursor_at_eol(void);
+int 		 iswordchar(unsigned char c);
+void		 find_next_word(void);
+void		 delete_next_word(void);
+void		 find_prev_word(void);
+void		 delete_prev_word(void);
+void		 delete_row(size_t at);
+void		 row_append_row(abuf *row, const char *s, int len);
+void		 row_insert_ch(abuf *row, int at, int16_t c);
+void		 row_delete_ch(abuf *row, int at);
+void		 insertch(int16_t c);
+void		 deletech(uint8_t op);
+void		 open_file(const char *filename);
+char		*rows_to_buffer(int *buflen);
+int     	 save_file(void);
+uint16_t	 is_arrow_key(int16_t c);
+int16_t		 get_keypress(void);
+char		*editor_prompt(const char*, void (*cb)(char*, int16_t));
+void		 editor_find_callback(char *query, int16_t c);
+void		 editor_find(void);
+void		 editor_openfile(void);
+int	    	 first_nonwhitespace(abuf *row);
+void		 move_cursor_once(int16_t c, int interactive);
+void		 move_cursor(int16_t c, int interactive);
+void		 uarg_start(void);
+void		 uarg_digit(int d);
+void		 uarg_clear(void);
+int	    	 uarg_get(void);
+void		 newline(void);
+char		*get_cloc_code_lines(const char *filename);
+int	    	 dump_pidfile(void);
+
+
+#endif

editor.c

@@ -17,30 +17,19 @@
  */
 struct editor editor = {
 	.cols = 0,
-	.rows = 0,
-	.curx = 0,
-	.cury = 0,
-	.rx = 0,
-	.mode = 0,
-	.nrows = 0,
-	.rowoffs = 0,
-	.coloffs = 0,
-	.row = NULL,
+	.rows     = 0,
+	.mode     = 0,
 	.killring = NULL,
-	.kill = 0,
-	.no_kill = 0,
-	.filename = NULL,
-	.dirty = 0,
-	.dirtyex = 0,
-	.mark_set = 0,
-	.mark_curx = 0,
-	.mark_cury = 0,
-	.uarg = 0,
-	.ucount = 0,
-	.msgtm = 0,
-	.buffers = NULL,
+	.kill     = 0,
+	.no_kill  = 0,
+	.dirtyex  = 0,
+	.uarg     = 0,
+	.ucount   = 0,
+	.msgtm    = 0,
+	.buffers  = NULL,
 	.bufcount = 0,
-	.curbuf = -1,
+	.curbuf   = 0,
+	.bufcap   = 0,
 };
 
 
@@ -69,26 +58,15 @@ init_editor(void)
 	editor.rows--; /* status bar */
 	editor.rows--; /* message line */
 
-	editor.curx = editor.cury = 0;
-	editor.rx   = 0;
-
-	editor.nrows   = 0;
-	editor.rowoffs = editor.coloffs = 0;
-	editor.row     = NULL;
-
 	/* don't clear out the kill ring:
 	 * killing / yanking across files is helpful, and killring
 	 * is initialized to NULL at program start.
 	 */
-	editor.kill    = 0;
+	editor.kill = 0;
 	editor.no_kill = 0;
 
 	editor.msg[0] = '\0';
-	editor.msgtm  = 0;
-
-	editor.dirty     = 0;
-	editor.mark_set  = 0;
-	editor.mark_cury = editor.mark_curx = 0;
+	editor.msgtm = 0;
 
 	/* initialize buffer system on first init */
 	if (editor.buffers == NULL && editor.bufcount == 0) {
@@ -101,25 +79,32 @@ init_editor(void)
 void
 reset_editor(void)
 {
-	/* Clear current working set. Notably, does not reset terminal
-	 * or buffers list. */
-	for (int i = 0; i < editor.nrows; i++) {
-		ab_free(&editor.row[i]);
-	}
-	free(editor.row);
-
-	editor.row     = NULL;
-	editor.nrows   = 0;
-	editor.rowoffs = editor.coloffs = 0;
-	editor.curx    = editor.cury    = 0;
-	editor.rx      = 0;
-
-	if (editor.filename != NULL) {
-		free(editor.filename);
-		editor.filename = NULL;
+	buffer *b = buffer_current();
+	if (b == NULL) {
+		return;
 	}
 
-	editor.dirty     = 0;
-	editor.mark_set  = 0;
-	editor.mark_cury = editor.mark_curx = 0;
+	if (b->row) {
+		for (size_t i = 0; i < b->nrows; i++) {
+			ab_free(&b->row[i]);
+		}
+		free(b->row);
+	}
+
+	b->row = NULL;
+	b->nrows = 0;
+	b->rowoffs = 0;
+	b->coloffs = 0;
+	b->rx = 0;
+	b->curx = 0;
+	b->cury = 0;
+	if (b->filename) {
+		free(b->filename);
+		b->filename = NULL;
+	}
+	b->dirty = 0;
+	b->mark_set = 0;
+	b->mark_curx = 0;
+	b->mark_cury = 0;
 }
+

editor.h

@@ -1,5 +1,5 @@
-#ifndef EDITOR_H
-#define EDITOR_H
+#ifndef KE_EDITOR_H
+#define KE_EDITOR_H
 
 #include <termios.h>
 #include <time.h>
@@ -9,32 +9,19 @@
 #include "buffer.h"
 
 
-/* TODO(kyle): remove the "per-buffer" fields completely from the editor. */
-
 struct editor {
-	int		  rows, cols;
-	int		  curx, cury;		/* per-buffer */
-	int		  rx;			/* per-buffer */
+	size_t		  rows, cols;
 	int		  mode;
-	int		  nrows;		/* per-buffer */
-	int		  rowoffs, coloffs;	/* per-buffer */
-	abuf		 *row;			/* per-buffer */
 	abuf		 *killring;
 	int		  kill;			/* KILL CHAIN (\m/) */
 	int		  no_kill;		/* don't kill in delete_row */
-	char		 *filename;		/* per-buffer */
-	int		  dirty;		/* per-buffer */
 	int		  dirtyex;
 	char		  msg[80];
-	int		  mark_set;		/* per-buffer */
-	int		  mark_curx, mark_cury;	/* per-buffer */
 	int		  uarg, ucount;		/* C-u support */
 	time_t		  msgtm;
-
-	/* Multi-buffer support */
 	struct buffer	**buffers;  /* array of buffers */
-	int		  bufcount; /* number of buffers */
-	int		  curbuf;   /* current buffer index */
+	size_t		  bufcount; /* number of buffers */
+	size_t		  curbuf;   /* current buffer index */
 	size_t		  bufcap;   /* current buffer capacity */
 };
 
@@ -45,4 +32,4 @@ void			 init_editor(void);
 void			 reset_editor(void);
 
 
-#endif /* EDITOR_H */
+#endif /* KE_EDITOR_H */

killring.c

@@ -0,0 +1,356 @@
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "abuf.h"
+#include "core.h"
+#include "editing.h"
+#include "editor.h"
+#include "killring.h"
+
+
+void
+killring_flush(void)
+{
+	if (editor.killring != NULL) {
+		ab_free(editor.killring);
+		free(editor.killring);
+		editor.killring = NULL;
+	}
+}
+
+
+void
+killring_yank(void)
+{
+	if (editor.killring == NULL) {
+		return;
+	}
+	/*
+	 * Insert killring contents at the cursor without clearing the ring.
+	 * Interpret '\n' as an actual newline() rather than inserting a raw 0x0A
+	 * byte, so yanked content preserves lines correctly.
+	 */
+	for (int i = 0; i < (int)editor.killring->size; i++) {
+		unsigned char ch = (unsigned char)editor.killring->b[i];
+		if (ch == '\n') {
+			newline();
+		} else {
+			insertch(ch);
+		}
+	}
+}
+
+
+void
+killring_start_with_char(unsigned char ch)
+{
+	abuf *row = NULL;
+
+	if (editor.killring != NULL) {
+		ab_free(editor.killring);
+		free(editor.killring);
+		editor.killring = NULL;
+	}
+
+	editor.killring = malloc(sizeof(abuf));
+	assert(editor.killring != NULL);
+	assert(erow_init(editor.killring, 0) == 0);
+
+	/* append one char to empty killring without affecting editor.dirty */
+	row = editor.killring;
+
+	row->b = realloc(row->b, row->size + 2);
+	assert(row->b != NULL);
+	row->b[row->size] = ch;
+	row->size++;
+	row->b[row->size] = '\0';
+}
+
+
+void
+killring_append_char(unsigned char ch)
+{
+	abuf	*row = NULL;
+
+	if (editor.killring == NULL) {
+		killring_start_with_char(ch);
+		return;
+	}
+
+	row = editor.killring;
+	row->b = realloc(row->b, row->size + 2);
+	assert(row->b != NULL);
+	row->b[row->size] = ch;
+	row->size++;
+	row->b[row->size] = '\0';
+}
+
+
+void
+killring_prepend_char(unsigned char ch)
+{
+	abuf	*row = NULL;
+
+	if (editor.killring == NULL) {
+		killring_start_with_char(ch);
+		return;
+	}
+
+	row = editor.killring;
+	row->b = realloc(row->b, row->size + 2);
+	assert(row->b != NULL);
+	memmove(&row->b[1], &row->b[0], row->size + 1);
+	row->b[0] = ch;
+	row->size++;
+}
+
+
+void
+toggle_markset(void)
+{
+	if (EMARK_SET) {
+		EMARK_SET = 0;
+		editor_set_status("Mark cleared.");
+		return;
+	}
+
+	EMARK_SET  = 1;
+	EMARK_CURX = ECURX;
+	EMARK_CURY = ECURY;
+	editor_set_status("Mark set.");
+}
+
+
+int
+cursor_after_mark(void)
+{
+	if (EMARK_CURY < ECURY) {
+		return 1;
+	}
+
+	if (EMARK_CURY > ECURY) {
+		return 0;
+	}
+
+	return ECURX >= EMARK_CURX;
+}
+
+
+int
+count_chars_from_cursor_to_mark(void)
+{
+	size_t	 count = 0;
+	size_t	 curx  = ECURX;
+	size_t	 cury  = ECURY;
+	size_t	 markx = EMARK_CURX;
+	size_t	 marky = EMARK_CURY;
+
+	if (!cursor_after_mark()) {
+		swap_size_t(&curx, &markx);
+		swap_size_t(&curx, &marky);
+	}
+
+	ECURX = markx;
+	ECURY = marky;
+
+	while (ECURY != cury) {
+		while (!cursor_at_eol()) {
+			move_cursor(ARROW_RIGHT, 1);
+			count++;
+		}
+
+		move_cursor(ARROW_RIGHT, 1);
+		count++;
+	}
+
+	while (ECURX != curx) {
+		count++;
+		move_cursor(ARROW_RIGHT, 1);
+	}
+
+	return count;
+}
+
+
+void
+kill_region(void)
+{
+	size_t	 curx  = ECURX;
+	size_t	 cury  = ECURY;
+	size_t	 markx = EMARK_CURX;
+	size_t	 marky = EMARK_CURY;
+
+	if (!EMARK_SET) {
+		return;
+	}
+
+	/* kill the current killring first */
+	killring_flush();
+
+	if (!cursor_after_mark()) {
+		swap_size_t(&curx, &markx);
+		swap_size_t(&cury, &marky);
+	}
+
+	ECURX = markx;
+	ECURY = marky;
+
+	while (ECURY != cury) {
+		while (!cursor_at_eol()) {
+			killring_append_char(EROW[ECURY].b[ECURX]);
+			move_cursor(ARROW_RIGHT, 0);
+		}
+		killring_append_char('\n');
+		move_cursor(ARROW_RIGHT, 0);
+	}
+
+	while (ECURX != curx) {
+		killring_append_char(EROW[ECURY].b[ECURX]);
+		move_cursor(ARROW_RIGHT, 0);
+	}
+
+	editor_set_status("Region killed.");
+	/* clearing the mark needs to be done outside this function;	*
+	 * when deleting the region, the mark needs to be set too.	*/
+}
+
+
+void
+indent_region(void)
+{
+	size_t	 start_row = 0;
+	size_t	 end_row   = 0;
+	size_t	 i         = 0;
+
+	if (!EMARK_SET) {
+		return;
+	}
+
+	if (EMARK_CURY < ECURY) {
+		start_row = EMARK_CURY;
+		end_row   = ECURY;
+	} else if (EMARK_CURY > ECURY) {
+		start_row = ECURY;
+		end_row   = EMARK_CURY;
+	} else {
+		start_row = end_row = ECURY;
+	}
+
+	/* Ensure bounds are valid */
+	if (end_row >= ENROWS) {
+		end_row = ENROWS - 1;
+	}
+
+	if (start_row >= ENROWS) {
+		return;
+	}
+
+	for (i = start_row; i <= end_row; i++) {
+		row_insert_ch(&EROW[i], 0, '\t');
+	}
+
+	ECURX = 0;
+	EDIRTY++;
+}
+
+
+void
+unindent_region(void)
+{
+	size_t	 start_row = 0;
+	size_t	 end_row   = 0;
+	size_t	 i         = 0;
+	size_t	 del       = 0;
+	abuf	*row       = NULL;
+
+	if (!EMARK_SET) {
+		editor_set_status("Mark not set.");
+		return;
+	}
+
+	if (EMARK_CURY < ECURY ||
+	    (EMARK_CURY == ECURY && EMARK_CURX < ECURX)) {
+		start_row = EMARK_CURY;
+		end_row   = ECURY;
+	} else {
+		start_row = ECURY;
+		end_row   = EMARK_CURY;
+	}
+
+	if (start_row >= ENROWS) {
+		return;
+	}
+
+	if (end_row >= ENROWS) {
+		end_row = ENROWS - 1;
+	}
+
+	for (i = start_row; i <= end_row; i++) {
+		row = &EROW[i];
+
+		if (row->size == 0) {
+			continue;
+		}
+
+		if (row->b[0] == '\t') {
+			row_delete_ch(row, 0);
+		} else if (row->b[0] == ' ') {
+			del = 0;
+
+			while (del < TAB_STOP && del < row->size &&
+			       row->b[del] == ' ') {
+				del++;
+			}
+
+			if (del > 0) {
+				/* +1 for NUL */
+				memmove(row->b, row->b + del,
+					row->size - del + 1);
+				row->size -= del;
+			}
+		}
+	}
+
+	ECURX = 0;
+	ECURY = start_row;
+
+	EDIRTY++;
+	editor_set_status("Region unindented");
+}
+
+
+void
+delete_region(void)
+{
+	size_t	 count  = count_chars_from_cursor_to_mark();
+	size_t	 killed = 0;
+	size_t	 curx   = ECURX;
+	size_t	 cury   = ECURY;
+	size_t	 markx  = EMARK_CURX;
+	size_t	 marky  = EMARK_CURY;
+
+	if (!EMARK_SET) {
+		return;
+	}
+
+	if (!cursor_after_mark()) {
+		swap_size_t(&curx, &markx);
+		swap_size_t(&cury, &marky);
+	}
+
+	jump_to_position(markx, marky);
+
+	while (killed < count) {
+		move_cursor(ARROW_RIGHT, 0);
+		deletech(KILLRING_NO_OP);
+		killed++;
+	}
+
+	while (ECURX != markx && ECURY != marky) {
+		deletech(KILLRING_NO_OP);
+	}
+
+	editor.kill = 1;
+	editor_set_status("Region killed.");
+}

killring.h

@@ -0,0 +1,26 @@
+#ifndef KE_KILLRING_H
+#define KE_KILLRING_H
+
+
+#define KILLRING_NO_OP		0	/* don't touch the killring */
+#define KILLRING_APPEND		1	/* append deleted chars */
+#define KILLRING_PREPEND	2	/* prepend deleted chars */
+#define KILLING_SET		3	/* set killring to deleted char */
+#define KILLRING_FLUSH		4	/* clear the killring */
+
+
+void		 killring_flush(void);
+void		 killring_yank(void);
+void		 killring_start_with_char(unsigned char ch);
+void		 killring_append_char(unsigned char ch);
+void		 killring_prepend_char(unsigned char ch);
+void		 toggle_markset(void);
+int	    	 cursor_after_mark(void);
+int	    	 count_chars_from_cursor_to_mark(void);
+void		 kill_region(void);
+void		 indent_region(void);
+void		 unindent_region(void);
+void		 delete_region(void);
+
+
+#endif

process.c

@@ -0,0 +1,438 @@
+#include <errno.h>
+#include <ctype.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <_string.h>
+
+#include "editing.h"
+#include "buffer.h"
+#include "core.h"
+#include "editor.h"
+#include "killring.h"
+#include "term.h"
+#include "process.h"
+
+
+void
+process_kcommand(const int16_t c)
+{
+	char	*buf   = NULL;
+	size_t	 len   = 0;
+	int	 jumpx = 0;
+	int	 jumpy = 0;
+	int	 reps  = 0;
+
+	switch (c) {
+		case BACKSPACE:
+			while (ECURX > 0) {
+				process_normal(BACKSPACE);
+			}
+			break;
+		case '=':
+			if (EMARK_SET) {
+				indent_region();
+			} else {
+				editor_set_status("Mark not set.");
+			}
+			break;
+		case '-':
+			if (EMARK_SET) {
+				unindent_region();
+			} else {
+				editor_set_status("Mark not set.");
+			}
+			break;
+		case CTRL_KEY('\\'):
+			/* sometimes it's nice to dump core */
+			disable_termraw();
+			abort();
+		case '@':
+			if (!dump_pidfile()) {
+				break;
+			}
+			/* FALLTHRU */
+		case '!':
+			/* useful for debugging */
+			editor_set_status("PID: %ld", (long) getpid());
+			break;
+		case ' ':
+			toggle_markset();
+			break;
+		case CTRL_KEY(' '):
+			jumpx = EMARK_CURX;
+			jumpy = EMARK_CURY;
+			EMARK_CURX = ECURX;
+			EMARK_CURY = ECURY;
+
+			jump_to_position(jumpx, jumpy);
+			editor_set_status("Jumped to mark");
+			break;
+		case 'c':
+			buffer_close_current();
+			break;
+		case 'd':
+			if (ECURX == 0 && cursor_at_eol()) {
+				delete_row(ECURY);
+				return;
+			}
+
+			reps = uarg_get();
+			while (reps--) {
+				while ((EROW[ECURY].size - ECURX) > 0) {
+					process_normal(DEL_KEY);
+				}
+				if (reps) {
+					newline();
+				}
+			}
+
+			break;
+		case DEL_KEY:
+		case CTRL_KEY('d'):
+			reps = uarg_get();
+
+			while (reps--) {
+				delete_row(ECURY);
+			}
+			break;
+		case 'e':
+		case CTRL_KEY('e'):
+			if (EDIRTY && editor.dirtyex) {
+				editor_set_status(
+					"File not saved - C-k e again to open a new file anyways.");
+				editor.dirtyex = 0;
+				return;
+			}
+			editor_openfile();
+			break;
+		case 'f':
+			if (editor.killring == NULL || editor.killring->size == 0) {
+				editor_set_status("The kill ring is empty.");
+				break;
+			}
+
+			len = editor.killring ? editor.killring->size : 0;
+			killring_flush();
+			editor_set_status("Kill ring cleared (%lu characters)", len);
+			break;
+		case 'n':
+			buffer_next();
+			break;
+		case 'p':
+			buffer_prev();
+			break;
+		case 'b':
+			buffer_switch_by_name();
+			break;
+		case 'g':
+			goto_line();
+			break;
+		case 'j':
+			if (!EMARK_SET) {
+				editor_set_status("Mark not set.");
+				break;
+			}
+
+			jumpx = EMARK_CURX;
+			jumpy = EMARK_CURY;
+			EMARK_CURX = ECURX;
+			EMARK_CURY = ECURY;
+
+			jump_to_position(jumpx, jumpy);
+			editor_set_status("Jumped to mark; mark is now the previous location.");
+			break;
+		case 'l':
+			buf = get_cloc_code_lines(EFILENAME);
+
+			editor_set_status("Lines of code: %s", buf);
+			free(buf);
+			break;
+		case 'm':
+			/* todo: fix the process failed: success issue */
+			if (system("make") != 0) {
+				editor_set_status(
+					"process failed: %s",
+					strerror(errno));
+			} else {
+				editor_set_status("make: ok");
+			}
+			break;
+		case 'q':
+			if (EDIRTY && editor.dirtyex) {
+				editor_set_status(
+					"File not saved - C-k q again to quit.");
+				editor.dirtyex = 0;
+				return;
+			}
+			exit(0);
+		case CTRL_KEY('q'):
+			exit(0);
+		case CTRL_KEY('r'):
+			if (EDIRTY && editor.dirtyex) {
+				editor_set_status("File not saved - C-k C-r again to reload.");
+				editor.dirtyex = 0;
+				return;
+			}
+
+			jumpx = ECURX;
+			jumpy = ECURY;
+			buf = strdup(EFILENAME);
+
+			reset_editor();
+			open_file(buf);
+			display_refresh();
+			free(buf);
+
+			jump_to_position(jumpx, jumpy);
+			editor_set_status("file reloaded");
+			break;
+		case CTRL_KEY('s'):
+		case 's':
+			save_file();
+			break;
+		case CTRL_KEY('x'):
+		case 'x':
+			exit(save_file());
+		case 'u':
+			reps = uarg_get();
+
+			while (reps--) {}
+			editor_set_status("Undo not implemented.");
+			break;
+		case 'U':
+			reps = uarg_get();
+
+			while (reps--) {}
+			editor_set_status("Redo not implemented.");
+			break;
+		case 'y':
+			reps = uarg_get();
+
+			while (reps--) {
+				killring_yank();
+			}
+			break;
+		case ESC_KEY:
+		case CTRL_KEY('g'):
+			break;
+		default:
+			if (isprint(c)) {
+				editor_set_status("unknown kcommand '%c'", c);
+				break;
+			}
+
+			editor_set_status("unknown kcommand: %04x", c);
+			return;
+	}
+
+	editor.dirtyex = 1;
+}
+
+
+void
+process_normal(int16_t c)
+{
+	size_t	 cols = 0;
+	size_t	 rows = 0;
+	int	 reps = 0;
+
+	/* C-u handling – must be the very first thing */
+	if (c == CTRL_KEY('u')) {
+		uarg_start();
+		return;
+	}
+
+	/* digits after a C-u are part of the argument */
+	if (editor.uarg && c >= '0' && c <= '9') {
+		uarg_digit(c - '0');
+		return;
+	}
+
+	if (is_arrow_key(c)) {
+		/* moving the cursor breaks a delete sequence */
+		editor.kill = 0;
+		move_cursor(c, 1);
+		return;
+	}
+
+	switch (c) {
+	case '\r':
+		newline();
+		break;
+	case CTRL_KEY('k'):
+		editor.mode = MODE_KCOMMAND;
+		return;
+	case BACKSPACE:
+	case CTRL_KEY('h'):
+	case CTRL_KEY('d'):
+	case DEL_KEY:
+		if (c == DEL_KEY || c == CTRL_KEY('d')) {
+			reps = uarg_get();
+			while (reps-- > 0) {
+				move_cursor(ARROW_RIGHT, 1);
+				deletech(KILLRING_APPEND);
+			}
+		} else {
+			reps = uarg_get();
+			while (reps-- > 0) {
+				deletech(KILLRING_PREPEND);
+			}
+		}
+		break;
+	case CTRL_KEY('a'):	/* beginning of line */
+	case HOME_KEY:
+		move_cursor(CTRL_KEY('a'), 1);
+		break;
+	case CTRL_KEY('e'):	/* end of line */
+	case END_KEY:
+		move_cursor(CTRL_KEY('e'), 1);
+		break;
+	case CTRL_KEY('g'):
+		break;
+	case CTRL_KEY('l'):
+		if (get_winsz(&rows, &cols) == 0) {
+			editor.rows = rows;
+			editor.cols = cols;
+		} else {
+			editor_set_status("Couldn't update window size.");
+		}
+		display_refresh();
+		break;
+	case CTRL_KEY('s'):
+		editor_find();
+		break;
+	case CTRL_KEY('w'):
+		kill_region();
+		delete_region();
+		toggle_markset();
+		break;
+	case CTRL_KEY('y'):
+		reps = uarg_get();
+
+		while (reps-- > 0) {
+			killring_yank();
+		}
+		break;
+	case ESC_KEY:
+		editor.mode = MODE_ESCAPE;
+		break;
+	default:
+		if (c == TAB_KEY) {
+			reps = uarg_get();
+
+			while (reps-- > 0) {
+				insertch(c);
+			}
+		} else if (c >= 0x20 && c != 0x7f) {
+			reps = uarg_get();
+
+			while (reps-- > 0) {
+				insertch(c);
+			}
+		}
+		break;
+	}
+
+	editor.dirtyex = 1;
+}
+
+
+void
+process_escape(const int16_t c)
+{
+	int	 reps = 0;
+
+	editor_set_status("hi");
+
+	switch (c) {
+		case '>':
+			ECURY = ENROWS;
+			ECURX = 0;
+			break;
+		case '<':
+			ECURY = 0;
+			ECURX = 0;
+			break;
+		case 'b':
+			reps = uarg_get();
+
+			while (reps--) {
+				find_prev_word();
+			}
+			break;
+		case 'd':
+			reps = uarg_get();
+
+			while (reps--) {
+				delete_next_word();
+			}
+			break;
+		case 'f':
+			reps = uarg_get();
+
+			while (reps--) {
+				find_next_word();
+			}
+			break;
+		case 'm':
+			toggle_markset();
+			break;
+		case 'w':
+			if (!EMARK_SET) {
+				editor_set_status("mark isn't set");
+				break;
+			}
+			kill_region();
+			toggle_markset();
+			break;
+		case BACKSPACE:
+			reps = uarg_get();
+
+			while (reps--) {
+				delete_prev_word();
+			}
+			break;
+		case ESC_KEY:
+		case CTRL_KEY('g'):
+			break; /* escape from escape-mode the movie */
+		default:
+			editor_set_status("unknown ESC key: %04x", c);
+	}
+
+	uarg_clear();
+}
+
+
+int
+process_keypress(void)
+{
+	const int16_t	 c = get_keypress();
+
+	if (c <= 0) {
+		return 0;
+	}
+
+	switch (editor.mode) {
+	case MODE_KCOMMAND:
+		process_kcommand(c);
+		editor.mode = MODE_NORMAL;
+		break;
+	case MODE_NORMAL:
+		process_normal(c);
+		break;
+	case MODE_ESCAPE:
+		process_escape(c);
+		editor.mode = MODE_NORMAL;
+		break;
+	default:
+		editor_set_status("we're in the %d-D space now cap'n",
+		                  editor.mode);
+		editor.mode = MODE_NORMAL;
+	}
+
+	return 1;
+}

process.h

@@ -0,0 +1,22 @@
+#ifndef KE_PROCESS_H
+#define KE_PROCESS_H
+
+
+#include <stdint.h>
+/*
+ * define the keyboard input modes
+ * normal: no special mode
+ * kcommand: ^k commands
+ * escape: what happens when you hit escape?
+ */
+#define	MODE_NORMAL		0
+#define	MODE_KCOMMAND		1
+#define	MODE_ESCAPE		2
+
+void		 process_kcommand(int16_t c);
+void		 process_normal(int16_t c);
+void		 process_escape(int16_t c);
+int	    	 process_keypress(void);
+
+
+#endif

scratch.c

@@ -2,15 +2,20 @@
  * scratch.c - ideas in progress
  */
 
+#include "buffer.h"
+#include "abuf.h"
+#include <ctype.h>
+#include <string.h>
+
 #define REFLOW_MARGIN		72
 
 void
 reflow_region(void)
 {
-	int		 start_row, end_row, i, col, wlen, this_len;
-	struct erow	*row;
-	struct abuf	 buf = ABUF_INIT;
-	struct abuf	 out = ABUF_INIT;
+ int		 start_row, end_row, i, col, wlen, this_len;
+ abuf		*row;
+ struct abuf	 buf = ABUF_INIT;
+ struct abuf	 out = ABUF_INIT;
 	int		 in_paragraph = 0;
 	int		 indent_len = 0;
 	char		 indent[REFLOW_MARGIN + 1];
@@ -19,38 +24,38 @@ reflow_region(void)
 	char		*p = NULL;
 	char		*s = NULL;
 
-	if (editor.mark_set) {
-		if (editor.mark_cury < editor.cury ||
-			(editor.mark_cury == editor.cury &&
-				editor.mark_curx < editor.curx)) {
-			start_row = editor.mark_cury;
-			end_row = editor.cury;
-		} else {
-			start_row = editor.cury;
-			end_row = editor.mark_cury;
-		}
-	} else {
-		start_row = end_row = editor.cury;
-		while (start_row > 0 && editor.row[start_row - 1].size > 0) {
-			start_row--;
-		}
+ if (EMARK_SET) {
+        if (EMARK_CURY < ECURY ||
+            (EMARK_CURY == ECURY &&
+                EMARK_CURX < ECURX)) {
+            start_row = EMARK_CURY;
+            end_row = ECURY;
+        } else {
+            start_row = ECURY;
+            end_row = EMARK_CURY;
+        }
+    } else {
+        start_row = end_row = ECURY;
+        while (start_row > 0 && EROW[start_row - 1].size > 0) {
+            start_row--;
+        }
 
-		while (end_row < editor.nrows - 1 &&
-			editor.row[end_row + 1].size > 0) {
-			end_row++;
-		}
-	}
+        while (end_row < ENROWS - 1 &&
+            EROW[end_row + 1].size > 0) {
+            end_row++;
+        }
+    }
 
-	if (start_row >= editor.nrows) {
-		return;
-	}
+ if (start_row >= ENROWS) {
+        return;
+    }
 
-	if (end_row >= editor.nrows) {
-		end_row = editor.nrows - 1;
-	}
+ if (end_row >= ENROWS) {
+        end_row = ENROWS - 1;
+    }
 
-	for (i = start_row; i <= end_row; i++) {
-		row = &editor.row[i];
+ for (i = start_row; i <= end_row; i++) {
+        row = &EROW[i];
 
 		if (row->size == 0) {
 			if (in_paragraph) {
@@ -62,21 +67,21 @@ reflow_region(void)
 			continue;
 		}
 
-		if (!in_paragraph) {
-			indent_len = 0;
-			while (indent_len < row->size &&
-				(row->line[indent_len] == ' ' ||
-					row->line[indent_len] == '\t')) {
-				indent[indent_len] = row->line[indent_len], indent_len++;
-			}
+        if (!in_paragraph) {
+            indent_len = 0;
+            while (indent_len < (int)row->size &&
+                (row->b[indent_len] == ' ' ||
+                    row->b[indent_len] == '\t')) {
+                indent[indent_len] = row->b[indent_len], indent_len++;
+            }
 
-			indent[indent_len] = '\0';
-			in_paragraph = 1;
-		}
+            indent[indent_len] = '\0';
+            in_paragraph = 1;
+        }
 
-		ab_append(&buf, row->line + indent_len, row->size - indent_len);
-		ab_append(&buf, " ", 1);
-	}
+        ab_append(&buf, row->b + indent_len, row->size - indent_len);
+        ab_append(&buf, " ", 1);
+    }
 
 	if (in_paragraph) {
 		ab_append(&buf, "\n", 1);
@@ -145,18 +150,57 @@ reflow_region(void)
 	ab_free(&out);
 
 
-	for (i = end_row; i >= start_row; i--) {
-		delete_row(i);
-	}
+ for (i = end_row; i >= start_row; i--) {
+        delete_row(i);
+    }
 
-	s = buf.b;
-	while ((e = strchr(s, '\n'))) {
-		erow_insert(start_row++, s, e - s);
-		s = e + 1;
-	}
+ s = buf.b;
+ while ((e = strchr(s, '\n'))) {
+     erow_insert(start_row++, s, e - s);
+     s = e + 1;
+ }
 
 	ab_free(&buf);
 
-	editor.dirty++;
-	editor_set_status("Region reflowed to %d columns", REFLOW_MARGIN);
-}
+    EDIRTY++;
+    editor_set_status("Region reflowed to %d columns", REFLOW_MARGIN);
+}
+
+
+static inline
+void clamp_curx_to_row(void)
+{
+	abuf	*row  = NULL;
+	int	 maxx = 0;
+
+	if (ECURY >= ENROWS) {
+		return;
+	}
+
+	row = &EROW[ECURY];
+	if (ECURX < 0) {
+		ECURX = 0;
+	}
+
+	maxx = (int) row->size;
+	if (ECURX > maxx) {
+		ECURX = maxx;
+	}
+}
+
+static inline
+void set_cursor(int col, int row)
+{
+	if (row < 0) {
+		row = 0;
+	}
+
+	if (row > ENROWS) {
+		row = ENROWS;
+	}
+	
+	ECURY = row;
+	ECURX = col;
+	
+	clamp_curx_to_row();
+}

term.c

@@ -1,13 +1,18 @@
+#include <sys/ioctl.h>
 #include <assert.h>
 #include <errno.h>
 #include <stdlib.h>
+#include <stdio.h>
 #include <string.h>
 #include <termios.h>
 #include <unistd.h>
-#include <sys/ioctl.h>
 
 #include "abuf.h"
 #include "core.h"
+#include "buffer.h"
+#include "editing.h"
+#include "editor.h"
+#include "process.h"
 #include "term.h"
 
 #define ESCSEQ "\x1b["
@@ -71,16 +76,237 @@ setup_terminal(void)
 
 
 int
-get_winsz(int *rows, int *cols)
+get_winsz(size_t *rows, size_t *cols)
 {
-	struct winsize ws;
+    struct winsize ws;
 
-	if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == -1 || ws.ws_col == 0) {
-		return -1;
+    if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == -1 || ws.ws_col == 0) {
+        return -1;
+    }
+
+    *cols = (size_t)ws.ws_col;
+    *rows = (size_t)ws.ws_row;
+
+    return 0;
+}
+
+
+void
+draw_rows(abuf *ab)
+{
+	abuf	*row              = NULL;
+	char	 buf[editor.cols];
+	char	 c                = 0;
+	size_t	 j                = 0;
+	size_t	 filerow          = 0;
+	size_t	 y                = 0;
+	size_t	 len              = 0;
+	size_t	 padding          = 0;
+	size_t	 printed          = 0;
+	size_t	 rx               = 0;
+
+	for (y = 0; y < editor.rows; y++) {
+		filerow = y + EROWOFFS;
+		if (filerow >= ENROWS) {
+			if ((ENROWS == 0) && (y == editor.rows / 3)) {
+				len = snprintf(buf,
+				               sizeof(buf),
+				               "%s",
+				               KE_VERSION);
+				padding = (editor.rows - len) / 2;
+
+				if (padding) {
+					ab_append(ab, "|", 1);
+					padding--;
+				}
+
+				while (padding--)
+					ab_append(ab, " ", 1);
+				ab_append(ab, buf, len);
+			} else {
+				ab_append(ab, "|", 1);
+			}
+		} else {
+			row = &EROW[filerow];
+			j = 0;
+			rx = printed = 0;
+
+			while (j < row->size && printed < editor.cols) {
+				c = row->b[j];
+
+				if (rx < ECOLOFFS) {
+					if (c == '\t') rx += (TAB_STOP - (rx % TAB_STOP));
+					else if (c < 0x20) rx += 3;
+					else rx++;
+					j++;
+					continue;
+				}
+
+				if (c == '\t') {
+					int sp = TAB_STOP - (rx % TAB_STOP);
+					for (int k = 0; k < sp && printed < editor.cols; k++) {
+						ab_appendch(ab, ' ');
+						printed++;
+						rx++;
+					}
+				} else if (c < 0x20) {
+					char seq[4];
+					snprintf(seq, sizeof(seq), "\\%02x", c);
+					ab_append(ab, seq, 3);
+					printed += 3;
+					rx += 3;
+				} else {
+					ab_appendch(ab, c);
+					printed++;
+					rx++;
+				}
+				j++;
+			}
+			len = printed;
+		}
+		ab_append(ab, ESCSEQ "K", 3);
+		ab_append(ab, "\r\n", 2);
+	}
+}
+
+
+char
+status_mode_char(void)
+{
+	switch (editor.mode) {
+	case MODE_NORMAL:
+		return 'N';
+	case MODE_KCOMMAND:
+		return 'K';
+	case MODE_ESCAPE:
+		return 'E';
+	default:
+		return '?';
+	}
+}
+
+
+void
+draw_status_bar(abuf *ab)
+{
+	char	 status[editor.cols];
+	char	 rstatus[editor.cols];
+	char	 mstatus[editor.cols];
+	size_t	 len                   = 0;
+	size_t	 rlen                  = 0;
+
+	len = snprintf(status,
+		       sizeof(status),
+		       "%c%cke: %.20s - %lu lines",
+		       status_mode_char(),
+		       EDIRTY ? '!' : '-',
+		       EFILENAME ? EFILENAME : "[no file]",
+                ENROWS);
+
+	if (EMARK_SET) {
+		snprintf(mstatus,
+		         sizeof(mstatus),
+		         " | M: %lu, %lu ",
+		         EMARK_CURX + 1,
+		         EMARK_CURY + 1);
+	} else {
+		snprintf(mstatus, sizeof(mstatus), " | M:clear ");
 	}
 
-	*cols = ws.ws_col;
-	*rows = ws.ws_row;
+	rlen = snprintf(rstatus,
+	                sizeof(rstatus),
+	                "L%lu/%lu C%lu %s",
+	                ECURY + 1,
+	                ENROWS,
+	                ECURX + 1,
+	                mstatus);
 
-	return 0;
+	ab_append(ab, ESCSEQ "7m", 4);
+	ab_append(ab, status, len);
+	while (len < editor.cols) {
+		if (editor.cols - len == rlen) {
+			ab_append(ab, rstatus, rlen);
+			break;
+		}
+		ab_append(ab, " ", 1);
+		len++;
+	}
+
+	ab_append(ab, ESCSEQ "m", 3);
+	ab_append(ab, "\r\n", 2);
+}
+
+
+void
+draw_message_line(abuf *ab)
+{
+	size_t	 len = strlen(editor.msg);
+
+	ab_append(ab, ESCSEQ "K", 3);
+	if (len > editor.cols) {
+		len = editor.cols;
+	}
+
+	if (len && time(NULL) - editor.msgtm < MSG_TIMEO) {
+		ab_append(ab, editor.msg, len);
+	}
+}
+
+
+void
+scroll(void)
+{
+	const abuf	*row = NULL;
+
+	ERX = 0;
+	if (ECURY < ENROWS) {
+		row = &EROW[ECURY];
+		ERX = erow_render_to_cursor(row, ECURX);
+	}
+
+	if (ECURY < EROWOFFS) {
+		EROWOFFS = ECURY;
+	}
+
+	if (ECURY >= EROWOFFS + editor.rows) {
+		EROWOFFS = ECURY - editor.rows + 1;
+	}
+
+	if (ERX < ECOLOFFS) {
+		ECOLOFFS = ERX;
+	}
+
+	if (ERX >= ECOLOFFS + editor.cols) {
+		ECOLOFFS = ERX - editor.cols + 1;
+	}
+}
+
+
+void
+display_refresh(void)
+{
+	char	 buf[32] = {0};
+	abuf	 ab      = ABUF_INIT;
+
+	scroll();
+
+	ab_append(&ab, ESCSEQ "?25l", 6);
+	ab_append(&ab, ESCSEQ "H", 3);
+	display_clear(&ab);
+
+	draw_rows(&ab);
+	draw_status_bar(&ab);
+	draw_message_line(&ab);
+
+	snprintf(buf,
+	         sizeof(buf),
+	         ESCSEQ "%lu;%luH",
+	         (ECURY - EROWOFFS) + 1,
+	         (ERX - ECOLOFFS) + 1);
+	ab_append(&ab, buf, kstrnlen(buf, 32));
+	/* ab_append(&ab, ESCSEQ "1;2H", 7); */
+	ab_append(&ab, ESCSEQ "?25h", 6);
+
+	kwrite(STDOUT_FILENO, ab.b, (int)ab.size);
+	ab_free(&ab);
 }

term.h

@@ -1,13 +1,20 @@
-#ifndef TERM_H
-#define TERM_H
+#ifndef KE_TERM_H
+#define KE_TERM_H
 
 #include "abuf.h"
 
+
 /* Terminal control/setup API */
-void enable_termraw(void);
-void disable_termraw(void);
-void setup_terminal(void);
-void display_clear(abuf *ab);
+void		 enable_termraw(void);
+void		 disable_termraw(void);
+void		 setup_terminal(void);
+void		 display_clear(abuf *ab);
+void		 draw_rows(abuf *ab);
+char		 status_mode_char(void);
+void		 draw_status_bar(abuf *ab);
+void		 draw_message_line(abuf *ab);
+void		 scroll(void);
+void		 display_refresh(void);
 
 /*
  * get_winsz uses the TIOCGWINSZ to get the window size.
@@ -17,6 +24,7 @@ void display_clear(abuf *ab);
  * on this for now because it's bloaty and this works on OpenBSD and
  * Linux, at least.
  */
-int  get_winsz(int *rows, int *cols);
+int  get_winsz(size_t *rows, size_t *cols);
 
-#endif /* TERM_H */
+
+#endif /* KE_TERM_H */

undo.c

@@ -1,8 +1,16 @@
+/*
+ * undo.c: ke's undo system
+ */
+
+#include <assert.h>
+#include <stdlib.h>
+
 #include "abuf.h"
+#include "buffer.h"
 #include "undo.h"
 
 
-undo_node
+undo_node *
 undo_node_new(undo_kind kind)
 {
 	undo_node	*node = NULL;
@@ -13,24 +21,23 @@ undo_node_new(undo_kind kind)
 	node->kind = kind;
 	node->row = node->col = 0;
 
-	abuf_init(node->text);
+	ab_init(&node->text);
 	
 	node->next = NULL;
-	node->parent = NULL;
+	node->next = NULL;
+
+	return node;
 }
 
 
 void
 undo_node_free(undo_node *node)
 {
-	undo_node	*next = NULL;
-
 	if (node == NULL) {
-		return NULL;
+		return;
 	}
 
-	abuf_free(node-text);
-	next = node->next;
+	ab_free(&node->text);
 }
 
 
@@ -44,9 +51,10 @@ undo_node_free_all(undo_node *node)
 	}
 
 	while (node != NULL) {
+		next = node->next;
 		undo_node_free(node);
 		free(node);
-		node = node->next;
+		node = next;
 	}
 }
 
@@ -65,7 +73,7 @@ undo_tree_init(undo_tree *tree)
 void
 undo_tree_free(undo_tree *tree)
 {
-	assert(tree == NULL);
+	assert(tree != NULL);
 
 	undo_node_free(tree->pending);
 	undo_node_free_all(tree->root);
@@ -86,19 +94,147 @@ undo_begin(undo_tree *tree, undo_kind kind)
 		undo_commit(tree);
 	}
 
-	pending = undo_new_new(kind);
+	pending = undo_node_new(kind);
 	assert(pending != NULL);
 
 	tree->pending = pending;
 }
 
 
-void		 undo_prepend(abuf *buf);
-void		 undo_append(buf *buf);
-void		 undo_prependch(char c);
-void		 undo_appendch(char c);
-void		 undo_commit(void);
-void		 undo_apply(undo_node *node);
-void		 editor_undo(void);
-void		 editor_redo(void);
+void
+undo_prepend(undo_tree *tree, abuf *buf)
+{
+	assert(tree != NULL);
+	assert(tree->pending != NULL);
+
+	ab_prepend_ab(&tree->pending->text, buf);
+}
+
+
+void
+undo_append(undo_tree *tree, abuf *buf)
+{
+	assert(tree != NULL);
+	assert(tree->pending != NULL);
+
+	ab_append_ab(&tree->pending->text, buf);
+}
+
+
+void
+undo_prependch(undo_tree *tree, char c)
+{
+	assert(tree != NULL);
+	assert(tree->pending != NULL);
+
+	ab_prependch(&tree->pending->text, c);
+}
+
+
+void
+undo_appendch(undo_tree *tree, char c)
+{
+	assert(tree != NULL);
+	assert(tree->pending != NULL);
+
+	ab_appendch(&tree->pending->text, c);
+}
+
+
+void
+undo_commit(undo_tree *tree)
+{
+	assert(tree != NULL);
+
+	if (tree->pending == NULL) {
+		return;
+	}
+
+	if (tree->root == NULL) {
+		assert(tree->current == NULL);
+
+		tree->root    = tree->pending;
+		tree->current = tree->pending;
+		tree->pending = NULL;
+
+		return;
+	}
+
+	assert(tree->current != NULL);
+	if (tree->current->next != NULL) {
+		undo_node_free_all(tree->current->next);
+	}
+
+	tree->pending->prev = tree->current;
+	tree->current->next = tree->pending;
+	tree->current       = tree->pending;
+	tree->pending       = NULL;
+}
+
+
+static int
+undo_apply_undo(struct buffer *buf)
+{
+	undo_node	*node = buf->undo.current;
+
+	switch (node->kind) {
+	case UNDO_INSERT:
+		break;
+	default:
+		return 0;
+	}
+
+	return 0;
+}
+
+
+int
+undo_apply(struct buffer *buf, int direction)
+{
+	(void)direction;
+
+	if (buf == NULL) {
+		return 0;
+	}
+
+	undo_commit(&buf->undo);
+	if (buf->undo.current == NULL) {
+		return 0;
+	}
+
+	if (direction == UNDO_DIR_UNDO) {
+		return undo_apply_undo(buf);
+	} else if (direction == UNDO_DIR_UNDO) {
+		return 0;
+	} else {
+		return 0;
+	}
+
+	return 0;
+}
+
+
+int
+editor_undo(struct buffer *buf)
+{
+	if (buf == NULL) {
+		return 0;
+	}
+
+	undo_commit(&buf->undo);
+	return undo_apply(buf, UNDO_DIR_UNDO);
+	
+}
+
+
+int
+editor_redo(struct buffer *buf)
+{
+	if (buf == NULL) {
+		return 0;
+	}
+
+	undo_commit(&buf->undo);
+	return undo_apply(buf, UNDO_DIR_REDO);
+}
 

undo.h

@@ -1,5 +1,17 @@
-#ifndef KE_UNDO
-#define KE_UNDO
+#include <stddef.h>
+
+#include "abuf.h"
+
+
+#ifndef KE_UNDO_H
+#define KE_UNDO_H
+
+
+struct	 buffer;
+
+
+#define		UNDO_DIR_UNDO		-1
+#define		UNDO_DIR_REDO		 1
 
 
 typedef enum undo_kind {
@@ -9,12 +21,12 @@ typedef enum undo_kind {
 
 
 typedef struct undo_node {
-	undo_kind		 op;
+	undo_kind		 kind;
 	size_t			 row, col;
 	abuf			 text;
 
 	struct undo_node	*next;
-	struct undo_node	*parent;
+	struct undo_node	*prev;
 
 } undo_node;
 
@@ -31,14 +43,14 @@ void		 undo_node_free(undo_node *node);
 void		 undo_tree_init(undo_tree *tree);
 void		 undo_tree_free(undo_tree *tree);
 void		 undo_begin(undo_tree *tree, undo_kind kind);
-void		 undo_prepend(abuf *buf);
-void		 undo_append(buf *buf);
-void		 undo_prependch(char c);
-void		 undo_appendch(char c);
+void		 undo_prepend(undo_tree *tree, abuf *buf);
+void		 undo_append(undo_tree *tree, abuf *buf);
+void		 undo_prependch(undo_tree *tree, char c);
+void		 undo_appendch(undo_tree *tree, char c);
 void		 undo_commit(undo_tree *tree);
-void		 undo_apply(undo_node *node);
-void		 editor_undo(void);
-void		 editor_redo(void);
+int		 undo_apply(struct buffer *buf, int direction);
+int		 editor_undo(struct buffer *buf);
+int		 editor_redo(struct buffer *buf);
 
 
 #endif