bump version

+ 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

.github/workflows/release.yml

@@ -10,29 +10,6 @@ permissions:
   contents: write
 
 jobs:
-  goreleaser:
-    name: GoReleaser
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-        with:
-          fetch-depth: 0
-
-      - name: Set up Go
-        uses: actions/setup-go@v5
-        with:
-          go-version-file: 'go.mod'
-          cache: true
-
-      - name: Run GoReleaser
-        uses: goreleaser/goreleaser-action@v6
-        with:
-          distribution: goreleaser
-          version: latest
-          args: release --clean
-        env:
-          GITHUB_TOKEN: ${{ secrets.GH_CPAT }}
   homebrew:
     name: Bump Homebrew formula
     # Skip this job in case of git pushes to prerelease tags
@@ -49,7 +26,7 @@ jobs:
       - uses: mislav/bump-homebrew-formula-action@v3
         with:
           formula-name: ke
-          formula-path: Formula/kw.rb
+          formula-path: Formula/ke.rb
           homebrew-tap: kisom/homebrew-tap
           base-branch: master
           commit-message: |

.gitignore

@@ -1,2 +1,4 @@
 *.log
 build
+ke
+*.txt

CMakeLists.txt

@@ -2,20 +2,37 @@ cmake_minimum_required(VERSION 3.15)
 project(ke C)  # Specify C language explicitly
 
 set(CMAKE_C_STANDARD 99)
-set(KE_VERSION "1.0.3")
+set(KE_VERSION "2.1.0")
 
-set(CMAKE_C_FLAGS "-Wall -Wextra -pedantic -Wshadow -Werror -std=c99 -g")
+set(CMAKE_C_FLAGS "-Wall -Wextra -pedantic -Wshadow -Werror -std=c99 -g -Werror=stringop-truncation")
 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -D_DEFAULT_SOURCE -D_XOPEN_SOURCE")
 
+# Optionally enable AddressSanitizer (ASan)
+option(ENABLE_ASAN "Enable AddressSanitizer for builds" OFF)
+
+if (ENABLE_ASAN)
+    message(STATUS "ASan enabled")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fsanitize=address -fno-omit-frame-pointer")
+    # Ensure the sanitizer is linked too (especially important on some platforms)
+    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -fsanitize=address")
+endif()
+
+include(GNUInstallDirs)
 
 # Add executable
-add_executable(ke main.c)
-
-# Define KE_VERSION for use in C code (e.g., #define KE_VERSION)
+add_executable(ke
+        abuf.c
+        term.c
+        buffer.c
+        editor.c
+        core.c
+        core.h
+        main.c
+)
 target_compile_definitions(ke PRIVATE KE_VERSION="ke version ${KE_VERSION}")
+install(TARGETS ke RUNTIME DESTINATION bin)
+install(FILES ke.1 TYPE MAN)
+
+install(TARGETS ke RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+install(FILES ke.1 DESTINATION ${CMAKE_INSTALL_MANDIR}/man1)
 
-# Set output properties
-set_target_properties(ke PROPERTIES
-        FOLDER bin
-        RUNTIME_OUTPUT_DIRECTORY bin
-)

Makefile

@@ -0,0 +1,40 @@
+TARGET :=		ke
+KE_VERSION :=		devel
+DEST :=			$(HOME)/.local/bin/$(TARGET)
+
+CFLAGS :=	-Wall -Wextra -pedantic -Wshadow -Werror -std=c99 -g
+CFLAGS +=	-Wno-unused-result
+CFLAGS +=	-D_DEFAULT_SOURCE -D_XOPEN_SOURCE
+CFLAGS +=	-fsanitize=address -fno-omit-frame-pointer 
+
+LDFLAGS :=	-fsanitize=address
+
+all: $(TARGET) test.txt
+
+SRCS := main.c abuf.c term.c buffer.c editor.c core.c
+HDRS :=        abuf.h term.h buffer.h editor.h core.h
+
+$(TARGET): $(SRCS)
+	$(CC) $(CFLAGS) -o $(TARGET) $(SRCS) $(LDFLAGS)
+
+.PHONY: install
+#install: $(TARGET) 
+install:
+	cp $(TARGET) $(DEST)
+
+clean:
+	rm -f $(TARGET)
+	rm -f asan.log*
+
+.PHONY: test.txt
+test.txt:
+	cp test.txt.bak $@
+
+.PHONY: gdb
+gdb:
+	@test -f $(TARGET).pid || (echo "error: $(TARGET).pid not found" >&2; exit 1)
+	@gdb -p $$(cat $(TARGET).pid | tr -d ' \t\n\r') ./$(TARGET)
+
+.PHONY: cloc
+cloc:
+	cloc $(SRCS) $(HDRS)

README.txt

@@ -6,4 +6,19 @@ used fairly often.
 
 See the man page for more info.
 
-Released under an ISC license.
+It should be available via homebrew, even:
+
+    brew tap kisom/homebrew-tap
+    brew install ke
+
+To get verbose ASAN messages:
+
+    export LSAN_OPTIONS=verbosity=1:log_threads=1
+
+Released under an ISC license.
+
+Started by following along with kilo:
+    https://viewsourcecode.org/snaptoken/kilo/
+
+E.g., in the devlogs
+    https://log.wntrmute.dev/2020/02/20200207

TODO

@@ -1,15 +1,18 @@
 [X] goto-line
 [X] text-corruption bug
 [ ] alt-modifiers
-[ ] refresh-screen
-[ ] functions -> keymapping?
+[x] refresh-screen
+[ ] functions -> keymapping? (what did this even mean)
 [X] rendering: need to skip over control characters like we do with tabs
 [X] control-d -> delete
-[ ] control-g -> exit buf prompt
-[ ] load-file prompt on dirty buffer
+[x] control-g -> exit buf prompt
+[x] load-file prompt on dirty buffer
 [ ] multiple files
+[x] utf-8
+[x] kill ring
+[x] mark/region
 
 What would it take for ke to be your daily drives?
-+ C-u
-+ Alt nav (backspace, delete, f, b, etc)
-
+[x] C-u (repeat actions)
+[x] Alt nav (backspace, delete, f, b, etc)
+[-] undo tree (C-k u/U)

abuf.c

@@ -0,0 +1,107 @@
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "abuf.h"
+#include "core.h"
+
+
+static void
+abuf_grow(abuf *buf, size_t delta)
+{
+	if (buf->cap - buf->size < delta) {
+		ab_resize(buf, buf->cap + delta);
+	}
+}
+
+
+void
+ab_init(abuf *buf)
+{
+	assert(buf != NULL);
+
+	buf->b    = NULL;
+	buf->size = buf->cap = 0;
+}
+
+
+void
+ab_init_cap(abuf *buf, const size_t cap)
+{
+	ab_init(buf);
+
+	if (cap > 0) {
+		ab_resize(buf, cap);
+	}
+}
+
+
+void
+ab_resize(abuf *buf, size_t cap)
+{
+	char	*newbuf = NULL;
+
+	cap = cap_growth(buf->cap, cap) + 1;
+	newbuf = realloc(buf->b, cap);
+	assert(newbuf != NULL);
+	buf->cap = cap;
+	buf->b   = newbuf;
+}
+
+
+void
+ab_appendch(abuf *buf, char c)
+{
+	abuf_grow(buf, 1);
+	ab_append(buf, &c, 1);
+}
+
+
+void
+ab_append(abuf *buf, const char *s, size_t len)
+{
+	char	*nc = NULL;
+
+	abuf_grow(buf, len);
+	nc = buf->b;
+
+	memcpy(&nc[buf->size], s, len);
+	buf->b = nc;
+	buf->size += len;
+}
+
+
+void
+ab_prependch(abuf *buf, const char c)
+{
+	abuf_grow(buf, 1);
+
+	ab_prepend(buf, &c, 1);
+}
+
+
+void
+ab_prepend(abuf *buf, const char *s, const size_t len)
+{
+	char	*nc = NULL;
+
+	abuf_grow(buf, len);
+	nc = buf->b;
+	assert(nc != NULL);
+
+	memmove(nc + len, nc, buf->size);
+	memcpy(nc, s, len);
+
+	buf->b = nc;
+	buf->size += len;
+}
+
+
+void
+ab_free(abuf *buf)
+{
+	free(buf->b);
+	buf->b    = NULL;
+	buf->size = 0;
+	buf->cap  = 0;
+}

abuf.h

@@ -0,0 +1,30 @@
+/*
+ * abuf.h - append/prepend buffer utilities
+ */
+#ifndef KE_ABUF_H
+#define KE_ABUF_H
+
+#include <stddef.h>
+
+
+typedef struct abuf {
+    char	*b;
+    size_t	 size;
+    size_t	 cap;
+} abuf;
+
+
+#define ABUF_INIT {NULL, 0, 0}
+
+
+void		 ab_init(abuf *buf);
+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_prependch(abuf *buf, const char c);
+void		 ab_prepend(abuf *buf, const char *s, const size_t len);
+void		 ab_free(abuf *buf);
+
+
+#endif

buffer.c

@@ -0,0 +1,466 @@
+/* buffer.c - multiple file buffers */
+
+#include <assert.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "abuf.h"
+#include "buffer.h"
+#include "core.h"
+#include "editor.h"
+
+
+#define		NO_NAME		 "[No Name]"
+
+
+/* externs from other modules */
+char *editor_prompt(const char *, void (*cb)(char *, int16_t));
+
+
+static const char *
+buf_basename(const char *path)
+{
+	if (path == NULL) {
+		return NULL;
+	}
+
+	const char *slash = strrchr(path, '/');
+	return (slash != NULL) ? (slash + 1) : path;
+}
+
+
+static int
+buffer_find_exact_by_name(const char *name)
+{
+	buffer	*b = NULL;
+	size_t   i = 0;
+
+	if (name == NULL) {
+		return -1;
+	}
+
+	for (i = 0; i < editor.bufcount; i++) {
+		b                = editor.buffers[i];
+		const char *full = b->filename;
+		const char *base = buf_basename(full);
+
+		if (full && strcmp(full, name) == 0) {
+			return i;
+		}
+
+		if (base && strcmp(base, name) == 0) {
+			return i;
+		}
+
+		if (full == NULL && strcmp(name, NO_NAME) == 0) {
+			return i;
+		}
+	}
+
+	return -1;
+}
+
+
+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;
+	size_t   i       = 0;
+	size_t	 plen    = (prefix ? strlen(prefix) : 0);
+
+	for (i = 0; i < editor.bufcount; i++) {
+		matched = 0;
+		b = editor.buffers[i];
+
+		const char *cand1 = b->filename;
+		const char *cand2 = buf_basename(cand1);
+
+		if (plen == 0) {
+			matched = 1; /* everything matches empty prefix */
+		} else {
+			if (cand2 && strncmp(cand2, prefix, plen) == 0) {
+				matched = 1;
+			} else if (cand1 && strncmp(cand1, prefix, plen) == 0) {
+				matched = 1;
+			} else if (!cand1 && strncmp(NO_NAME, prefix, plen) == 0) {
+				matched = 1;
+			}
+		}
+
+		if (matched) {
+			if (count < max_out) {
+				out_idx[count] = i;
+			}
+			count++;
+		}
+	}
+
+	return count;
+}
+
+
+static void
+longest_common_prefix(char *buf, const size_t bufsz, const int *idxs, const int n)
+{
+	const char *first = NULL;
+	const char *cand  = NULL;
+	int k             = 0;
+	size_t j          = 0;
+	size_t cur        = 0;
+	size_t lcp        = 0;
+	size_t to_copy    = 0;
+
+	if (n <= 0) {
+		return;
+	}
+
+	first = buf_basename(editor.buffers[idxs[0]]->filename);
+	if (first == NULL) {
+		first = NO_NAME;
+	}
+
+	lcp = strnlen(first, FILENAME_MAX);
+	for (k = 1; k < n; k++) {
+		cand = buf_basename(editor.buffers[idxs[k]]->filename);
+		if (cand == NULL) {
+			cand = NO_NAME;
+		}
+
+		j = 0;
+		while (j < lcp && first[j] == cand[j]) {
+			j++;
+		}
+
+		lcp = j;
+		if (lcp == 0) {
+			break;
+		}
+	}
+
+	cur = strlen(buf);
+	if (lcp > cur) {
+		to_copy = lcp - cur;
+		if (cur + to_copy >= bufsz) {
+			to_copy = bufsz - cur - 1;
+		}
+
+		strncat(buf, first + cur, to_copy);
+	}
+}
+
+
+static void
+buffer_switch_prompt_cb(char *buf, const int16_t key)
+{
+	char msg[80]     = {0};
+	const char *name = NULL;
+	const char *nm   = NULL;
+	int idxs[64]     = {0};
+	int n            = 0;
+	size_t need      = 0;
+	size_t used      = 0;
+
+	if (key != TAB_KEY) {
+		return;
+	}
+
+	n = buffer_collect_prefix_matches(buf, idxs, 64);
+	if (n <= 0) {
+		editor_set_status("No matches");
+		return;
+	}
+
+	if (n == 1) {
+		name = buf_basename(editor.buffers[idxs[0]]->filename);
+		if (name == NULL) {
+			name = NO_NAME;
+		}
+
+		need = strlen(name);
+		if (need < 128) {
+			memcpy(buf, name, need);
+			buf[need] = '\0';
+		}
+
+		editor_set_status("Unique match: %s", name);
+		return;
+	}
+
+	longest_common_prefix(buf, 128, idxs, n);
+	msg[0] = '\0';
+	used   = 0;
+	used += snprintf(msg + used, sizeof(msg) - used, "%d matches: ", n);
+	for (int i = 0; i < n && used < sizeof(msg) - 1; i++) {
+		nm = buf_basename(editor.buffers[idxs[i]]->filename);
+		if (nm == NULL) {
+			nm = NO_NAME;
+		}
+
+		used += snprintf(msg + used, sizeof(msg) - used, "%s%s",
+		                 nm, (i == n - 1 ? "" : ", "));
+	}
+
+	editor_set_status("%s", msg);
+}
+
+
+const char *
+buffer_name(buffer *b)
+{
+	if (b && b->filename) {
+		return buf_basename(b->filename);
+	}
+
+	return NO_NAME;
+}
+
+
+void
+buffers_init(void)
+{
+    int	 idx = 0;
+
+ editor.buffers  = NULL;
+ editor.bufcount = 0;
+ editor.curbuf   = 0;
+ editor.bufcap	= 0;
+
+	idx = buffer_add_empty();
+	buffer_switch(idx);
+}
+
+
+static void
+buffer_list_resize(void)
+{
+    buffer	**newlist = NULL;
+
+    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);
+        editor.buffers = newlist;
+    }
+}
+
+
+int
+buffer_add_empty(void)
+{
+    buffer	 *buf    = NULL;
+    int	 idx     = 0;
+
+    buffer_list_resize();
+
+    buf = calloc(1, sizeof(buffer));
+    assert(buf != NULL);
+
+	buf->curx      = 0;
+	buf->cury      = 0;
+	buf->rx        = 0;
+	buf->nrows     = 0;
+	buf->rowoffs   = 0;
+	buf->coloffs   = 0;
+	buf->row       = NULL;
+	buf->filename  = NULL;
+	buf->dirty     = 0;
+	buf->mark_set  = 0;
+	buf->mark_curx = 0;
+	buf->mark_cury = 0;
+
+    editor.buffers[editor.bufcount] = buf;
+    idx                             = (int)editor.bufcount;
+    editor.bufcount++;
+    return idx;
+}
+
+
+void
+buffer_save_current(void)
+{
+    /* No-op: editor no longer mirrors per-buffer fields */
+    (void)editor;
+}
+
+
+buffer *
+buffer_current(void)
+{
+    if (editor.bufcount == 0 || editor.curbuf >= editor.bufcount) {
+        return NULL;
+    }
+    return editor.buffers[editor.curbuf];
+}
+
+
+int
+buffer_is_unnamed_and_empty(const buffer *b)
+{
+	if (b == NULL) {
+		return 0;
+	}
+
+	if (b->filename != NULL) {
+		return 0;
+	}
+
+	if (b->dirty) {
+		return 0;
+	}
+
+	if (b->nrows != 0) {
+		return 0;
+	}
+
+	if (b->row != NULL) {
+		return 0;
+	}
+
+	return 1;
+}
+
+
+void
+buffer_switch(const int idx)
+{
+    buffer	*b = NULL;
+
+    if (idx < 0 || (size_t)idx >= editor.bufcount) {
+        return;
+    }
+
+    if (editor.curbuf == (size_t)idx) {
+        return;
+    }
+
+    b = editor.buffers[idx];
+    editor.curbuf  = (size_t)idx;
+    editor.dirtyex = 1;
+    editor_set_status("Switched to buffer %d: %s", editor.curbuf, buffer_name(b));
+}
+
+
+void
+buffer_next(void)
+{
+    size_t idx = 0;
+
+    if (editor.bufcount <= 1) {
+        return;
+    }
+
+    idx = (editor.curbuf + 1) % editor.bufcount;
+    buffer_switch((int)idx);
+}
+
+
+void
+buffer_prev(void)
+{
+    size_t	 idx = 0;
+
+    if (editor.bufcount <= 1) {
+        return;
+    }
+
+    idx = (editor.curbuf == 0) ? (editor.bufcount - 1) : (editor.curbuf - 1);
+    buffer_switch((int)idx);
+}
+
+
+void
+buffer_close_current(void)
+{
+    buffer	*b   = NULL;
+    size_t	 closing = 0;
+    int	 target  = 0;
+    int	 nb      = 0;
+
+	/* sanity check */
+	if (editor.bufcount == 0 || editor.curbuf >= editor.bufcount) {
+		editor_set_status("No buffer to close.");
+		return;
+	}
+
+	closing = editor.curbuf;
+
+	if (editor.bufcount > 1) {
+		target = (closing > 0) ? (int) (closing - 1) : (int) (closing + 1);
+		buffer_switch(target);
+	} else {
+		nb = buffer_add_empty();
+		buffer_switch(nb);
+	}
+
+	b = editor.buffers[closing];
+	if (b) {
+		if (b->row) {
+			for (size_t i = 0; i < b->nrows; i++) {
+				ab_free(&b->row[i]);
+			}
+			free(b->row);
+		}
+
+		if (b->filename) {
+			free(b->filename);
+		}
+		free(b);
+	}
+
+	memmove(&editor.buffers[closing], &editor.buffers[closing + 1],
+		sizeof(buffer *) * (editor.bufcount - closing - 1));
+
+	editor.bufcount--;
+	if (editor.bufcount == 0) {
+		editor.curbuf = 0;
+	} else {
+		if (editor.curbuf > closing) {
+			editor.curbuf--;
+		}
+	}
+
+	editor.dirtyex = 1;
+	editor_set_status("Closed buffer. Now on %s",
+			  buffer_name(editor.buffers[editor.curbuf]));
+}
+
+
+void
+buffer_switch_by_name(void)
+{
+	int	 idxs[64] = {0};
+	char	*name   = NULL;
+	int	 idx      = 0;
+	int	 n        = 0;
+
+	if (editor.bufcount <= 1) {
+		editor_set_status("No other buffers.");
+		return;
+	}
+
+	name = editor_prompt("Switch buffer (name, TAB to complete): %s", buffer_switch_prompt_cb);
+	if (name == NULL) {
+		return;
+	}
+
+	idx = buffer_find_exact_by_name(name);
+	if (idx < 0) {
+		n = buffer_collect_prefix_matches(name, idxs, 64);
+		if (n == 1) {
+			idx = idxs[0];
+		}
+	}
+
+	if (idx >= 0) {
+		buffer_switch(idx);
+	} else {
+		editor_set_status("No open buffer: %s", name);
+	}
+
+	free(name);
+}

buffer.h

@@ -0,0 +1,49 @@
+#ifndef KE_BUFFER_H
+#define KE_BUFFER_H
+
+#include "abuf.h"
+
+
+typedef struct buffer {
+	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;
+} buffer;
+
+/* Access current buffer and convenient aliases for file-specific fields */
+buffer		*buffer_current(void);
+
+#define CURBUF			(buffer_current())
+#define EROW			(CURBUF->row)
+#define ENROWS			(CURBUF->nrows)
+#define ECURX			(CURBUF->curx)
+#define ECURY			(CURBUF->cury)
+#define ERX			(CURBUF->rx)
+#define EROWOFFS		(CURBUF->rowoffs)
+#define ECOLOFFS		(CURBUF->coloffs)
+#define EFILENAME		(CURBUF->filename)
+#define EDIRTY			(CURBUF->dirty)
+#define EMARK_SET		(CURBUF->mark_set)
+#define EMARK_CURX		(CURBUF->mark_curx)
+#define EMARK_CURY		(CURBUF->mark_cury)
+
+
+void		 buffers_init(void);
+int		 buffer_add_empty(void);
+void		 buffer_save_current(void);
+void		 buffer_switch(int idx);
+void		 buffer_next(void);
+void		 buffer_prev(void);
+void		 buffer_switch_by_name(void);
+void		 buffer_close_current(void);
+const char	*buffer_name(buffer *b);
+int		 buffer_is_unnamed_and_empty(const buffer *b);
+
+
+#endif

core.c

@@ -0,0 +1,113 @@
+#include <assert.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#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.
+ */
+char *
+strnstr(const char *s, const char *find, size_t slen)
+{
+	char	 c, sc;
+	size_t	 len;
+
+	if ((c = *find++) != '\0') {
+		len = strlen(find);
+		do {
+			do {
+				if (slen-- < 1 || (sc = *s++) == '\0')
+					return (NULL);
+			} while (sc != c);
+			if (len > slen)
+				return (NULL);
+		} while (strncmp(s, find, len) != 0);
+		s--;
+	}
+	return ((char*)s);
+}
+#endif
+
+
+void
+swap_size_t(size_t *first, size_t *second)
+{
+	*first ^= *second;
+	*second ^= *first;
+	*first ^= *second;
+}
+
+
+int
+next_power_of_2(int n)
+{
+	if (n < 2) {
+		n = 2;
+	}
+
+	n--;
+	n |= n >> 1;
+	n |= n >> 2;
+	n |= n >> 4;
+	n |= n >> 8;
+	n |= n >> 16;
+
+	return n + 1;
+}
+
+
+int
+cap_growth(int cap, int sz)
+{
+	if (cap == 0) {
+		cap = INITIAL_CAPACITY;
+	}
+
+	while (cap <= sz) {
+		cap = next_power_of_2(cap + 1);
+	}
+
+	return cap;
+}
+
+
+size_t
+kstrnlen(const char *buf, const size_t max)
+{
+	if (buf == NULL) {
+		return 0;
+	}
+
+	return strnlen(buf, max);
+}
+
+
+void
+kwrite(const int fd, const char* buf, const int len)
+{
+	int wlen = 0;
+
+	wlen = write(fd, buf, len);
+	assert(wlen != -1);
+	assert(wlen == len);
+	if (wlen == -1) {
+		abort();
+	}
+}
+
+
+void
+die(const char* s)
+{
+	kwrite(STDOUT_FILENO, "\x1b[2J", 4);
+	kwrite(STDOUT_FILENO, "\x1b[H", 3);
+
+	perror(s);
+	exit(1);
+}

core.h

@@ -0,0 +1,39 @@
+#ifndef KE_CORE_H
+#define KE_CORE_H
+
+#include <stddef.h>
+
+
+#define		INITIAL_CAPACITY	8
+
+
+typedef enum key_press {
+	TAB_KEY     = 9,
+	ESC_KEY     = 27,
+	BACKSPACE   = 127,
+	ARROW_LEFT  = 1000,
+	ARROW_RIGHT = 1001,
+	ARROW_UP    = 1002,
+	ARROW_DOWN  = 1003,
+	DEL_KEY     = 1004,
+	HOME_KEY    = 1005,
+	END_KEY     = 1006,
+	PG_UP       = 1007,
+	PG_DN       = 1008,
+} key_press;
+
+
+#ifndef strnstr
+char	*strnstr(const char *s, const char *find, size_t slen);
+#define	INCLUDE_STRNSTR
+#endif
+
+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

default.nix

@@ -0,0 +1,40 @@
+{
+  lib,
+  stdenv,
+  cmake,
+  installShellFiles,
+  ...
+}:
+let
+  cmakeContent = builtins.readFile ./CMakeLists.txt;
+  cmakeLines = lib.splitString "\n" cmakeContent;
+  versionLine = lib.findFirst (l: builtins.match ".*set\\(KE_VERSION \".+\"\\).*" l != null) (throw "KE_VERSION not found in CMakeLists.txt") cmakeLines;
+  version = builtins.head (builtins.match ".*set\\(KE_VERSION \"(.+)\"\\).*" versionLine);
+in
+stdenv.mkDerivation {
+  pname = "ke";
+  inherit version;
+
+  src = lib.cleanSource ./.;
+
+  nativeBuildInputs = [
+    cmake
+    installShellFiles
+  ];
+
+  cmakeFlags = [
+    "-DENABLE_ASAN=on"
+    "-DCMAKE_BUILD_TYPE=Debug"
+  ];
+
+  installPhase = ''
+    runHook preInstall
+
+    mkdir -p $out/bin
+    cp ke $out/bin/
+
+    installManPage ../ke.1
+
+    runHook postInstall
+  '';
+}

editor.c

@@ -0,0 +1,109 @@
+/* editor.c - editor-wide state and functions */
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#include "abuf.h"
+#include "buffer.h"
+#include "core.h"
+#include "editor.h"
+#include "term.h"
+
+/*
+ * Global editor instance
+ */
+struct editor editor = {
+    .cols = 0,
+	.rows     = 0,
+	.mode     = 0,
+	.killring = NULL,
+	.kill     = 0,
+	.no_kill  = 0,
+	.dirtyex  = 0,
+	.uarg     = 0,
+	.ucount   = 0,
+	.msgtm    = 0,
+	.buffers  = NULL,
+	.bufcount = 0,
+	.curbuf   = 0,
+	.bufcap   = 0,
+};
+
+
+void
+editor_set_status(const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	vsnprintf(editor.msg, sizeof(editor.msg), fmt, ap);
+	va_end(ap);
+
+	editor.msgtm = time(NULL);
+}
+
+
+void
+init_editor(void)
+{
+	editor.cols = 0;
+	editor.rows = 0;
+
+	if (get_winsz(&editor.rows, &editor.cols) == -1) {
+		die("can't get window size");
+	}
+	editor.rows--; /* status bar */
+	editor.rows--; /* message line */
+
+	/* 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.no_kill = 0;
+
+	editor.msg[0] = '\0';
+	editor.msgtm = 0;
+
+	/* initialize buffer system on first init */
+	if (editor.buffers == NULL && editor.bufcount == 0) {
+		editor.bufcap = 0;
+		buffers_init();
+	}
+}
+
+
+void
+reset_editor(void)
+{
+	/* Reset the current buffer's contents/state. */
+	buffer *b = buffer_current();
+	if (b == NULL) {
+		return;
+	}
+
+	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

@@ -0,0 +1,35 @@
+#ifndef KE_EDITOR_H
+#define KE_EDITOR_H
+
+#include <termios.h>
+#include <time.h>
+
+
+#include "abuf.h"
+#include "buffer.h"
+
+
+struct editor {
+	size_t		  rows, cols;
+	int		  mode;
+	abuf		 *killring;
+	int		  kill;			/* KILL CHAIN (\m/) */
+	int		  no_kill;		/* don't kill in delete_row */
+	int		  dirtyex;
+	char		  msg[80];
+	int		  uarg, ucount;		/* C-u support */
+	time_t		  msgtm;
+	struct buffer	**buffers;  /* array of buffers */
+	size_t		  bufcount; /* number of buffers */
+	size_t		  curbuf;   /* current buffer index */
+	size_t		  bufcap;   /* current buffer capacity */
+};
+
+
+extern struct editor	 editor;
+void			 editor_set_status(const char *fmt, ...);
+void			 init_editor(void);
+void			 reset_editor(void);
+
+
+#endif /* KE_EDITOR_H */

flake.lock

@@ -0,0 +1,27 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1763835633,
+        "narHash": "sha256-HzxeGVID5MChuCPESuC0dlQL1/scDKu+MmzoVBJxulM=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "050e09e091117c3d7328c7b2b7b577492c43c134",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,18 @@
+{
+  description = "Kyle's Text Editor";
+
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
+  };
+
+  outputs =
+    { self, nixpkgs }:
+    let
+      pkgs = import nixpkgs { system = "x86_64-linux"; };
+    in
+    {
+      packages.x86_64-linux = {
+        default = pkgs.callPackage ./default.nix { };
+      };
+    };
+}

ke.1

@@ -19,32 +19,89 @@ is
 K-command mode is entered using C-k. This is taken from Wordstar and just
 so happens to be blessed with starting with a most excellent letter of
 grandeur. Many commands work with and without control; for example,
-saving a file can be done with either C-k s or C-k C-s.
-.Pp
+saving a file can be done with either C-k s or C-k C-s. Other commands work
+with ESC or CTRL.
+.Sh K-COMMANDS
+k-command mode can be exited with ESC or C-g.
 .Bl -tag -width xxxxxxxxxxxx -offset indent
 .It C-k BACKSPACE
 Delete from the cursor to the beginning of the line.
-.It C-k C-d
-Delete the current row.
+.It C-k SPACE
+Toggle the mark.
+.It C-k -
+If the mark is set, unindent the region.
+.It C-k =
+If the mark is set, indent the region.
+.It C-k b
+Switch to a buffer.
+.It C-k c
+Close the current buffer. If no other buffers are open, an empty
+buffer will be opened. To exit, use C-k q.
 .It C-k d
 Delete from the cursor to the end of the line.
+.It C-k C-d
+Delete the entire line.
 .It C-k e
 Edit a new file. Also C-k C-e.
 .It C-k f
-Incremental find.
+Flush the kill ring.
 .It C-k g
-Go to a specific line. Also C-k C-g.
+Go to a specific line.
+.It C-k j
+Jump to the mark.
+.It C-k l
+List the number of lines of code in a saved file.
 .It C-k m
 Run make(1).
+.It C-k p
+Switch to the next buffer.
 .It C-k q
-exit the editor. Also C-k C-q.
+Exit the editor. If the file has unsaved changes,
+a warning will be printed; a second C-k q will exit.
+.It C-k C-q
+Immediately exit the editor.
+.It C-k C-r
+Reload the current buffer from disk.
 .It C-k s
-save the file, prompting for a filename if needed. Also C-k C-s.
+Save the file, prompting for a filename if needed. Also C-k C-s.
+.It C-k u
+Undo changes (not implemented; marking this k-command as taken).
+.It C-k U
+Redo changes (not implemented; marking this k-command as taken).
 .It C-k x
 save the file and exit. Also C-k C-x.
-.It C-k \
+.It C-k y
+Yank the kill ring.
+.It C-k \[char92]
 Dump core.
 .El
+.Sh OTHER KEYBINDINGS
+.Bl -tag -width xxxxxxxxxxxx -offset indent
+.It C-g
+In general, C-g cancels an operation.
+.It C-l
+Refresh the display.
+.It C-s
+Incremental find.
+.It C-u
+Universal argument. C-u followed by numbers will repeat an
+operation n times.
+.It C-w
+Kill the region if the mark is set.
+.It C-y
+Yank the kill ring.
+.It ESC BACKSPACE
+Delete the previous word.
+.It ESC b
+Move to the previous word.
+.It ESC d
+Delete the next word.
+.It ESC f
+Move to the next word.
+.It ESC w
+Save the region (if the mark is set) to the kill ring.
+.It
+.El
 .Sh FIND
 The find operation is an incremental search. The up or left arrow keys will
 go to the previous result, while the down or right arrow keys will go to

scratch.c

@@ -0,0 +1,206 @@
+/*
+ * 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;
+ 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];
+	char		 word[REFLOW_MARGIN + 1];
+	char		*e = NULL;
+	char		*p = NULL;
+	char		*s = NULL;
+
+ 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 < ENROWS - 1 &&
+            EROW[end_row + 1].size > 0) {
+            end_row++;
+        }
+    }
+
+ 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) {
+			if (in_paragraph) {
+				ab_append(&buf, "\n", 1);
+				in_paragraph = 0;
+			}
+
+			ab_append(&buf, "\n", 1);
+			continue;
+		}
+
+        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;
+        }
+
+        ab_append(&buf, row->b + indent_len, row->size - indent_len);
+        ab_append(&buf, " ", 1);
+    }
+
+	if (in_paragraph) {
+		ab_append(&buf, "\n", 1);
+	}
+
+
+	p = buf.b;
+	col = 0;
+
+	while (p != NULL && *p != '\0') {
+		while (*p && isspace((unsigned char)*p) &&
+			*p != '\n') {
+			p++;
+		}
+
+		if (*p == '\0') {
+			break;
+		}
+
+		wlen = 0;
+		while (*p && !isspace((unsigned char)*p)) {
+			if (wlen < REFLOW_MARGIN)
+				word[wlen++] = *p;
+			p++;
+		}
+		word[wlen] = '\0';
+
+		if (*p == '\n' && (p[1] == '\n' || p[1] == '\0')) {
+			ab_append(&out, "\n", 1); /* flush */
+			col = 0;
+			p++; /* consume the extra \n */
+			continue;
+		}
+
+		this_len = wlen;
+		if (col > 0) {
+			this_len++; /* space before word */
+		}
+
+		if (col == 0) {
+			ab_append(&out, indent, indent_len);
+			col = indent_len;
+		}
+
+		if (col + this_len > REFLOW_MARGIN && col > 0) {
+			ab_append(&out, "\n", 1);
+			ab_append(&out, indent, indent_len);
+			col = indent_len;
+		}
+
+		if (col > 0) {
+			ab_append(&out, " ", 1);
+			col++;
+		}
+
+		ab_append(&out, word, wlen);
+		col += wlen;
+	}
+
+	if (col > 0) {
+		ab_append(&out, "\n", 1);
+	}
+
+	/* the old switcharoo */
+	buf = out;
+	ab_free(&out);
+
+
+ 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;
+ }
+
+	ab_free(&buf);
+
+    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

@@ -0,0 +1,86 @@
+#include <assert.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <termios.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+
+#include "abuf.h"
+#include "core.h"
+#include "term.h"
+
+#define ESCSEQ "\x1b["
+
+
+static struct termios saved_entry_term;
+
+
+void
+enable_termraw(void)
+{
+	struct termios raw;
+
+	if (tcgetattr(STDIN_FILENO, &raw) == -1) {
+		die("tcgetattr while enabling raw mode");
+	}
+
+	cfmakeraw(&raw);
+	raw.c_cc[VMIN]  = 0;
+	raw.c_cc[VTIME] = 1;
+
+	if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &raw) == -1) {
+		die("tcsetattr while enabling raw mode");
+	}
+}
+
+
+void
+display_clear(abuf *ab)
+{
+	if (ab == NULL) {
+		kwrite(STDOUT_FILENO, ESCSEQ "2J", 4);
+		kwrite(STDOUT_FILENO, ESCSEQ "H", 3);
+	} else {
+		ab_append(ab, ESCSEQ "2J", 4);
+		ab_append(ab, ESCSEQ "H", 3);
+	}
+}
+
+
+void
+disable_termraw(void)
+{
+	display_clear(NULL);
+
+	if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &saved_entry_term) == -1) {
+		die("couldn't disable terminal raw mode");
+	}
+}
+
+
+void
+setup_terminal(void)
+{
+	if (tcgetattr(STDIN_FILENO, &saved_entry_term) == -1) {
+		die("can't snapshot terminal settings");
+	}
+
+	enable_termraw();
+}
+
+
+int
+get_winsz(size_t *rows, size_t *cols)
+{
+    struct winsize ws;
+
+    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;
+}

term.h

@@ -0,0 +1,22 @@
+#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);
+
+/*
+ * get_winsz uses the TIOCGWINSZ to get the window size.
+ *
+ * there's a fallback way to do this, too, that involves moving the
+ * cursor down and to the left \x1b[999C\x1b[999B. I'm going to skip
+ * on this for now because it's bloaty and this works on OpenBSD and
+ * Linux, at least.
+ */
+int  get_winsz(size_t *rows, size_t *cols);
+
+#endif /* KE_TERM_H */

test.txt.bak

@@ -0,0 +1,15 @@
+hello
+
+
+
+
+
+
+
+
+
+
+
+
+world it is 	me
+	but I am not me

undo.c

@@ -0,0 +1,114 @@
+#include <assert.h>
+#include <stdlib.h>
+#include "abuf.h"
+#include "undo.h"
+
+
+undo_node *
+undo_node_new(undo_kind kind)
+{
+	undo_node	*node = NULL;
+
+	node = (undo_node *)malloc(sizeof(undo_node));
+	assert(node != NULL);
+
+	node->kind = kind;
+	node->row = node->col = 0;
+
+	ab_init(&node->text);
+	
+	node->next = NULL;
+	node->parent = NULL;
+
+	return node;
+}
+
+
+void
+undo_node_free(undo_node *node)
+{
+	undo_node	*next = NULL;
+
+	if (node == NULL) {
+		return;
+	}
+
+	ab_free(&node->text);
+}
+
+
+void
+undo_node_free_all(undo_node *node)
+{
+	undo_node	*next = NULL;
+
+	if (node == NULL) {
+		return;
+	}
+
+	while (node != NULL) {
+		next = node->next;
+		undo_node_free(node);
+		free(node);
+		node = next;
+	}
+}
+
+
+void
+undo_tree_init(undo_tree *tree)
+{
+	assert(tree != NULL);
+
+	tree->root    = NULL;
+	tree->current = NULL;
+	tree->pending = NULL;
+}
+
+
+void
+undo_tree_free(undo_tree *tree)
+{
+	assert(tree != NULL);
+
+	undo_node_free(tree->pending);
+	undo_node_free_all(tree->root);
+	undo_tree_init(tree);
+}
+
+
+void
+undo_begin(undo_tree *tree, undo_kind kind)
+{
+	undo_node	*pending = NULL;
+	
+	if (tree->pending != NULL) {
+		if (tree->pending->kind == kind) {
+			/* don't initiate a new undo sequence if it's the same kind */
+			return;
+		}
+		undo_commit(tree);
+	}
+
+	pending = undo_node_new(kind);
+	assert(pending != NULL);
+
+	tree->pending = pending;
+}
+
+
+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(struct editor *editor);
+void		 editor_undo(undo_tree *tree);
+void		 editor_redo(undo_tree *tree);
+

undo.h

@@ -0,0 +1,50 @@
+#include <stddef.h>
+
+#include "abuf.h"
+#include "editor.h"
+
+
+#ifndef KE_UNDO_H
+#define KE_UNDO_H
+
+
+typedef enum undo_kind {
+	UNDO_INSERT  = 1 << 0,
+	UNDO_UNKNOWN = 1 << 1,
+} undo_kind;
+
+
+typedef struct undo_node {
+	undo_kind		 kind;
+	size_t			 row, col;
+	abuf			 text;
+
+	struct undo_node	*next;
+	struct undo_node	*parent;
+
+} undo_node;
+
+
+typedef struct undo_tree {
+	undo_node	*root;		/* the start of the undo sequence */
+	undo_node	*current;	/* where we are currently at */
+	undo_node	*pending;	/* the current undo operations being built */
+} undo_tree;
+
+
+undo_node	*undo_node_new(undo_kind kind);
+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(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(struct editor *editor);
+void		 editor_undo(undo_tree *tree);
+void		 editor_redo(undo_tree *tree);
+
+
+#endif