kst/ke/main.c

1454 lines
25 KiB
C

/*
* kyle's editor
*
* first version is a run-through of the kilo editor walkthrough as a
* set of guiderails. I've made a lot of changes and did some things
* differently. keep an eye for for kte, kyle's text editor - the
* rewrite that will be coming out... when it comes out.
*
* https://viewsourcecode.org/snaptoken/kilo/
*/
#include <sys/ioctl.h>
#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <termios.h>
#include <time.h>
#include <unistd.h>
#define ESCSEQ "\x1b["
#define CTRL_KEY(key) ((key)&0x1f)
#define TAB_STOP 8
#define MSG_TIMEO 3
/*
* 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
#define TAB_STOP 8
/*
* Function declarations.
*/
/* append buffer */
struct abuf {
char *b;
int len;
int cap;
};
#define ABUF_INIT {NULL, 0, 0}
void ab_append(struct abuf *buf, const char *s, int len);
void ab_free(struct abuf *buf);
/* editor row */
struct erow {
char *line;
char *render;
int size;
int rsize;
};
char nibble_to_hex(char c);
int erow_render_to_cursor(struct erow *row, int cx);
int erow_cursor_to_render(struct erow *row, int rx);
void erow_update(struct erow *row);
void erow_insert(int at, char *s, int len);
void erow_free(struct erow *row);
void editor_set_status(const char *fmt, ...);
/* miscellaneous */
void die(const char *s);
int get_winsz(int *rows, int *cols);
void goto_line(void);
void delete_row(int at);
void row_append_row(struct erow *row, char *s, int len);
void row_insert_ch(struct erow *row, int at, int16_t c);
void row_delete_ch(struct erow *row, int at);
void insertch(int16_t c);
void deletech(void);
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);
void display_refresh(void);
void editor_find_callback(char *query, int16_t c);
void editor_find(void);
char *editor_prompt(char *, void (*cb)(char *, int16_t));
void editor_openfile(void);
void move_cursor(int16_t c);
void newline(void);
void process_kcommand(int16_t c);
void process_normal(int16_t c);
void process_escape(int16_t c);
int process_keypress(void);
void enable_termraw(void);
void display_clear(struct abuf *ab);
void disable_termraw(void);
void setup_terminal(void);
void draw_rows(struct abuf *ab);
char status_mode_char(void);
void draw_status_bar(struct abuf *ab);
void draw_message_line(struct abuf *ab);
void scroll(void);
void display_refresh(void);
void editor_set_status(const char *fmt, ...);
void loop(void);
void init_editor(void);
void process_normal(int16_t c);
enum KeyPress {
TAB_KEY = 9,
ESC_KEY = 27,
BACKSPACE = 127,
ARROW_LEFT = 1000,
ARROW_RIGHT,
ARROW_UP,
ARROW_DOWN,
DEL_KEY,
HOME_KEY,
END_KEY,
PG_UP,
PG_DN,
};
/*
* editor is the global editor state; it should be broken out
* to buffers and screen state, probably.
*/
struct editor_t {
struct termios entry_term;
int rows, cols;
int curx, cury;
int rx;
int mode;
int nrows;
int rowoffs, coloffs;
struct erow *row;
char *filename;
int dirty;
int dirtyex;
char msg[80];
time_t msgtm;
} editor;
void
ab_append(struct abuf *buf, const char *s, int len)
{
char *nc = buf->b;
int sz = buf->len + len;
if (sz >= buf->cap) {
while (sz > buf->cap) {
if (buf->cap == 0) {
buf->cap = 1;
} else {
buf->cap *= 2;
}
}
nc = realloc(nc, buf->cap);
assert(nc != NULL);
}
memcpy(&nc[buf->len], s, len);
buf->b = nc;
buf->len += len; /* DANGER: overflow */
}
void
ab_free(struct abuf *buf)
{
free(buf->b);
buf->b = NULL;
buf->len = 0;
buf->cap = 0;
}
char
nibble_to_hex(char c)
{
c &= 0xf;
if (c < 10) {
return c + 0x30;
}
return c + 0x41;
}
int
erow_render_to_cursor(struct erow *row, int cx)
{
int rx = 0;
int j;
for (j = 0; j < cx; j++) {
if (row->line[j] == '\t') {
rx += (TAB_STOP-1) - (rx%TAB_STOP);
} else if (row->line[j] < 0x20) {
rx += 2;
}
rx++;
}
return rx;
}
int
erow_cursor_to_render(struct erow *row, int rx)
{
int cur_rx = 0;
int curx = 0;
for (curx = 0; curx < row->size; curx++) {
if (row->line[curx] == '\t') {
cur_rx += (TAB_STOP - 1) - (cur_rx % TAB_STOP);
} else if (row->line[curx] < 0x20) {
cur_rx += 2;
}
cur_rx++;
if (cur_rx > rx) {
break;
}
}
return curx;
}
void
erow_update(struct erow *row)
{
int i = 0, j;
int tabs = 0;
int ctrl = 0;
/*
* TODO(kyle): I'm not thrilled with this double-render.
*/
for (j = 0; j < row->size; j++) {
if (row->line[j] == '\t') {
tabs++;
} else if (!isprint(row->line[j])) {
ctrl++;
}
}
if (row->rsize) {
free(row->render);
row->rsize = 0;
}
row->render = NULL;
row->render = malloc(row->size + (tabs * (TAB_STOP-1)) + (ctrl * 3) + 1);
assert(row->render != NULL);
for (j = 0; j < row->size; j++) {
if (row->line[j] == '\t') {
do {
row->render[i++] = ' ';
} while ((i % TAB_STOP) != 0);
} else if (!isprint(row->line[j])) {
row->render[i++] = '\\';
row->render[i++] = nibble_to_hex(row->line[j] >> 4);
row->render[i++] = nibble_to_hex(row->line[j] & 0x0f);
} else {
row->render[i++] = row->line[j];
}
}
row->render[i] = '\0';
row->rsize = i;
}
void
erow_insert(int at, char *s, int len)
{
if (at < 0 || at > editor.nrows) {
return;
}
editor.row = realloc(editor.row, sizeof(struct erow) * (editor.nrows + 1));
assert(editor.row != NULL);
if (at < editor.nrows) {
memmove(&editor.row[at+1], &editor.row[at],
sizeof(struct erow) * (editor.nrows - at + 1));
}
editor.row[at].size = len;
editor.row[at].line = malloc(len+1);
memcpy(editor.row[at].line, s, len);
editor.row[at].line[len] = '\0';
editor.row[at].rsize = 0;
editor.row[at].render = NULL;
erow_update(&editor.row[at]);
editor.nrows++;
}
void
erow_free(struct erow *row)
{
free(row->render);
free(row->line);
row->render = NULL;
row->line = NULL;
}
void
die(const char *s)
{
/*
* NOTE(kyle): this is a duplication of the code in display.c
* but I would like to be able to import these files from there.
*/
write(STDOUT_FILENO, "\x1b[2J", 4);
write(STDOUT_FILENO, "\x1b[H", 3);
perror(s);
exit(1);
}
/*
* 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(int *rows, int *cols)
{
struct winsize ws;
if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == -1 ||
ws.ws_col == 0) {
return -1;
}
*cols = ws.ws_col;
*rows = ws.ws_row;
return 0;
}
void
goto_line()
{
int lineno = 0;
char *query = editor_prompt("Line: %s", NULL);
if (query == NULL) {
return;
}
lineno = atoi(query);
if (lineno < 1 || lineno >= editor.nrows) {
editor_set_status("Line number must be between 1 and %d.", editor.nrows);
return;
}
editor.cury = lineno - 1;
editor.rowoffs = editor.cury - (editor.rows / 2);
}
void
delete_row(int at)
{
if (at < 0 || at >= editor.nrows) {
return;
}
erow_free(&editor.row[at]);
memmove(&editor.row[at], &editor.row[at+1],
sizeof(struct erow) * (editor.nrows - at - 1));
editor.nrows--;
editor.dirty++;
}
void
row_append_row(struct erow *row, char *s, int len)
{
row->line = realloc(row->line, row->size + len + 1);
assert(row->line != NULL);
memcpy(&row->line[row->size], s, len);
row->size += len;
row->line[row->size] = '\0';
erow_update(row);
editor.dirty++;
}
void
row_insert_ch(struct erow *row, int at, int16_t c)
{
/*
* row_insert_ch just concerns itself with how to update a row.
*/
if ((at < 0) || (at > row->size)) {
at = row->size;
}
assert(c > 0);
row->line = realloc(row->line, row->size+2);
assert(row->line != NULL);
memmove(&row->line[at+1], &row->line[at], row->size - at + 1);
row->size++;
row->line[at] = c & 0xff;
erow_update(row);
}
void
row_delete_ch(struct erow *row, int at)
{
if (at < 0 || at >= row->size) {
return;
}
memmove(&row->line[at], &row->line[at+1], row->size-at);
row->size--;
erow_update(row);
editor.dirty++;
}
void
insertch(int16_t c)
{
/*
* insert_ch doesn't need to worry about how to update a
* a row; it can just figure out where the cursor is
* at and what to do.
*/
if (editor.cury == editor.nrows) {
erow_insert(editor.nrows, "", 0);
}
row_insert_ch(&editor.row[editor.cury], editor.curx, (char)(c & 0xff));
editor.curx++;
editor.dirty++;
}
void
deletech()
{
struct erow *row = NULL;
if (editor.cury >= editor.nrows) {
return;
}
if (editor.cury == 0 && editor.curx == 0) {
return;
}
row = &editor.row[editor.cury];
if (editor.curx > 0) {
row_delete_ch(row, editor.curx - 1);
editor.curx--;
} else {
editor.curx = editor.row[editor.cury - 1].size;
row_append_row(&editor.row[editor.cury - 1], row->line,
row->size);
delete_row(editor.cury);
editor.cury--;
}
}
void
open_file(const char *filename)
{
char *line = NULL;
size_t linecap = 0;
ssize_t linelen;
FILE *fp = NULL;
free(editor.filename);
editor.filename = strdup(filename);
assert(editor.filename != NULL);
editor.dirty = 0;
if ((fp = fopen(filename, "r")) == NULL) {
if (errno == ENOENT) {
editor_set_status("[new file]");
return;
}
die("fopen");
}
while ((linelen = getline(&line, &linecap, fp)) != -1) {
if (linelen != -1) {
while ((linelen > 0) && ((line[linelen-1] == '\r') ||
(line[linelen-1] == '\n'))) {
linelen--;
}
erow_insert(editor.nrows, line, linelen);
}
}
free(line);
line = NULL;
fclose(fp);
}
/*
* convert our rows to a buffer; caller must free it.
*/
char *
rows_to_buffer(int *buflen)
{
int len = 0;
int j;
char *buf = NULL;
char *p = NULL;
for (j = 0; j < editor.nrows; j++) {
/* extra byte for newline */
len += editor.row[j].size+1;
}
if (len == 0) {
return NULL;
}
*buflen = len;
buf = malloc(len);
assert(buf != NULL);
p = buf;
for (j = 0; j < editor.nrows; j++) {
memcpy(p, editor.row[j].line, editor.row[j].size);
p += editor.row[j].size;
*p++ = '\n';
}
return buf;
}
int
save_file()
{
int fd = -1;
int len;
int status = 1; /* will be used as exit code */
char *buf;
if (!editor.dirty) {
editor_set_status("No changes to save.");
return 0;
}
if (editor.filename == NULL) {
editor.filename = editor_prompt("Filename: %s", NULL);
if (editor.filename == NULL) {
editor_set_status("Save aborted.");
return 0;
}
}
buf = rows_to_buffer(&len);
if ((fd = open(editor.filename, O_RDWR|O_CREAT, 0644)) == -1) {
goto save_exit;
}
if (-1 == ftruncate(fd, len)) {
goto save_exit;
}
if (len == 0) {
status = 0;
goto save_exit;
}
if ((ssize_t)len != write(fd, buf, len)) {
goto save_exit;
}
status = 0;
save_exit:
if (fd) close(fd);
if (buf) {
free(buf);
buf = NULL;
}
if (status != 0) {
buf = strerror(errno);
editor_set_status("Error writing %s: %s", editor.filename,
buf);
} else {
editor_set_status("Wrote %d bytes to %s.", len,
editor.filename);
editor.dirty = 0;
}
return status;
}
uint16_t
is_arrow_key(int16_t c)
{
switch (c) {
case ARROW_DOWN:
case ARROW_LEFT:
case ARROW_RIGHT:
case ARROW_UP:
case CTRL_KEY('p'):
case CTRL_KEY('n'):
case CTRL_KEY('f'):
case CTRL_KEY('b'):
case CTRL_KEY('a'):
case CTRL_KEY('e'):
case END_KEY:
case HOME_KEY:
case PG_DN:
case PG_UP:
return 1;
};
return 0;
}
int16_t
get_keypress()
{
char seq[3];
char c = -1;
if (read(STDIN_FILENO, &c, 1) == -1) {
die("get_keypress:read");
}
if (c == 0x1b) {
if (read(STDIN_FILENO, &seq[0], 1) != 1) return c;
if (read(STDIN_FILENO, &seq[1], 1) != 1) return c;
if (seq[0] == '[') {
if (seq[1] < 'A') {
if (read(STDIN_FILENO, &seq[2], 1) != 1)
return c;
if (seq[2] == '~') {
switch (seq[1]) {
case '1': return HOME_KEY;
case '3': return DEL_KEY;
case '4': return END_KEY;
case '5': return PG_UP;
case '6': return PG_DN;
case '7': return HOME_KEY;
case '8': return END_KEY;
}
}
} else {
switch (seq[1]) {
case 'A': return ARROW_UP;
case 'B': return ARROW_DOWN;
case 'C': return ARROW_RIGHT;
case 'D': return ARROW_LEFT;
case 'F': return END_KEY;
case 'H': return HOME_KEY;
default:
/* nada */ ;
}
}
} else if (seq[0] == 'O') {
switch (seq[1]) {
case 'F': return END_KEY;
case 'H': return HOME_KEY;
}
}
return 0x1b;
}
return c;
}
char *
editor_prompt(char *prompt, void (*cb)(char *, int16_t))
{
size_t bufsz = 128;
char *buf = malloc(bufsz);
size_t buflen = 0;
int16_t c;
buf[0] = '\0';
while (1) {
editor_set_status(prompt, buf);
display_refresh();
while ((c = get_keypress()) <= 0) ;
if (c == DEL_KEY || c == CTRL_KEY('h') || c == BACKSPACE) {
if (buflen != 0) {
buf[--buflen] = '\0';
}
} else if (c == ESC_KEY || c == CTRL_KEY('g')) {
editor_set_status("");
if (cb) {
cb(buf, c);
}
free(buf);
return NULL;
} else if (c == '\r') {
if (buflen != 0) {
editor_set_status("");
if (cb) {
cb(buf, c);
}
return buf;
}
} else if (!iscntrl(c) && c < 128) {
if (buflen == bufsz - 1) {
bufsz *= 2;
buf = realloc(buf, bufsz);
assert(buf != NULL);
}
buf[buflen++] = c;
buf[buflen] = '\0';
}
if (cb) {
cb(buf, c);
}
}
}
void
editor_find_callback(char *query, int16_t c)
{
static int lmatch = -1;
static int dir = 1;
int i, current;
char *match;
struct erow *row;
if (c == '\r' || c == ESC_KEY) {
/* reset search */
lmatch = -1;
dir = 1;
return;
} else if (c == ARROW_RIGHT || c == ARROW_DOWN || c == CTRL_KEY('s')) {
dir = 1;
} else if (c == ARROW_LEFT || c == ARROW_UP) {
dir = -1;
} else {
lmatch = -1;
dir = 1;
}
if (lmatch == -1) {
dir = 1;
}
current = lmatch;
for (i = 0; i < editor.nrows; i++) {
current += dir;
if (current == -1) {
current = editor.nrows - 1;
} else if (current == editor.nrows) {
current = 0;
}
row = &editor.row[current];
match = strstr(row->render, query);
if (match) {
lmatch = current;
editor.cury = current;
editor.curx = erow_render_to_cursor(row,
match - row->render);
if (editor.curx > row->size) {
editor.curx = row->size;
}
/*
* after this, scroll will put the match line at
* the top of the screen.
*/
editor.rowoffs = editor.nrows;
break;
}
}
display_refresh();
}
void
editor_find()
{
char *query;
int scx = editor.curx;
int scy = editor.cury;
int sco = editor.coloffs;
int sro = editor.rowoffs;
query = editor_prompt("Search (ESC to cancel): %s",
editor_find_callback);
if (query) {
free(query);
} else {
editor.curx = scx;
editor.cury = scy;
editor.coloffs = sco;
editor.rowoffs = sro;
}
display_refresh();
}
void
editor_openfile()
{
char *filename;
/* TODO(kyle): combine with dirutils for tab-completion */
filename = editor_prompt("Load file: %s", NULL);
if (filename == NULL) {
return;
}
free(editor.row);
init_editor();
open_file(filename);
}
void
move_cursor(int16_t c)
{
struct erow *row;
int reps;
row = (editor.cury >= editor.nrows) ? NULL : &editor.row[editor.cury];
switch (c) {
case ARROW_UP:
case CTRL_KEY('p'):
if (editor.cury > 0) {
editor.cury--;
}
break;
case ARROW_DOWN:
case CTRL_KEY('n'):
if (editor.cury < editor.nrows) {
editor.cury++;
}
break;
case ARROW_RIGHT:
case CTRL_KEY('f'):
if (row && editor.curx < row->size) {
editor.curx++;
} else if (row && editor.curx == row->size) {
editor.cury++;
editor.curx = 0;
}
break;
case ARROW_LEFT:
case CTRL_KEY('b'):
if (editor.curx > 0) {
editor.curx--;
} else if (editor.cury > 0) {
editor.cury--;
editor.curx = editor.row[editor.cury].size;
}
break;
case PG_UP:
case PG_DN: {
if (c == PG_UP) {
editor.cury = editor.rowoffs;
} else if (c == PG_DN) {
editor.cury = editor.rowoffs + editor.rows-1;
if (editor.cury > editor.nrows) {
editor.cury = editor.nrows;
}
}
reps = editor.rows;
while (--reps) {
move_cursor(c == PG_UP ? ARROW_UP : ARROW_DOWN);
}
break;
}
case HOME_KEY:
case CTRL_KEY('a'):
editor.curx = 0;
break;
case END_KEY:
case CTRL_KEY('e'):
if (editor.nrows == 0) {
break;
}
editor.curx = editor.row[editor.cury].size;
break;
default:
break;
}
row = (editor.cury >= editor.nrows) ?
NULL : &editor.row[editor.cury];
reps = row ? row->size : 0;
if (editor.curx > reps) {
editor.curx = reps;
}
}
void
newline()
{
struct erow *row = NULL;
if (editor.curx == 0) {
erow_insert(editor.cury, "", 0);
} else {
row = &editor.row[editor.cury];
erow_insert(editor.cury + 1, &row->line[editor.curx],
row->size - editor.curx);
row = &editor.row[editor.cury];
row->size = editor.curx;
row->line[row->size] = '\0';
erow_update(row);
}
editor.cury++;
editor.curx = 0;
}
void
process_kcommand(int16_t c)
{
switch (c) {
case 'q':
case CTRL_KEY('q'):
if (editor.dirty && editor.dirtyex) {
editor_set_status("File not saved - C-k q again to quit.");
editor.dirtyex = 0;
return;
}
exit(0);
case CTRL_KEY('s'):
case 's':
save_file();
break;
case CTRL_KEY('w'):
case 'w':
exit(save_file());
case 'd':
while ((editor.row[editor.cury].size - editor.curx) > 0) {
process_normal(DEL_KEY);
}
break;
case 'g':
case CTRL_KEY('g'):
goto_line();
break;
case BACKSPACE:
while (editor.curx > 0) {
process_normal(BACKSPACE);
}
break;
case CTRL_KEY('\\'):
/* sometimes it's nice to dump core */
disable_termraw();
abort();
case 'e':
case CTRL_KEY('e'):
editor_openfile();
break;
case 'f':
editor_find();
break;
case 'm':
if (system("make") != 0) {
editor_set_status("process failed: %s", strerror(errno));
} else {
editor_set_status("make: ok");
}
break;
}
editor.dirtyex = 1;
return;
}
void
process_normal(int16_t c)
{
if (is_arrow_key(c)) {
move_cursor(c);
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')) {
move_cursor(ARROW_RIGHT);
}
deletech();
break;
case CTRL_KEY('l'):
display_refresh();
break;
case CTRL_KEY('s'):
editor_find();
break;
case ESC_KEY:
editor.mode = MODE_ESCAPE;
break;
default:
if (isprint(c) || c == TAB_KEY) {
insertch(c);
}
break;
}
editor.dirtyex = 1;
}
void
process_escape(int16_t c)
{
struct erow *row = &editor.row[editor.cury];
editor_set_status("hi");
switch (c) {
case '>':
editor.cury = editor.nrows;
editor.curx = 0;
break;
case '<':
editor.cury = 0;
editor.curx = 0;
break;
case BACKSPACE:
if (isalnum(row->line[editor.curx])) {
editor_set_status("is alnum");
while (editor.curx > 0 && isalnum(row->line[editor.curx])) {
process_normal(BACKSPACE);
}
} else {
editor_set_status("not alnum");
process_normal(BACKSPACE);
}
break;
default:
editor_set_status("unknown ESC key: %04x", c);
}
}
int
process_keypress()
{
int16_t c = get_keypress();
/* we didn't actually read a key */
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;
}
/*
* A text editor needs the terminal to be in raw mode; but the default
* is to be in canonical (cooked) mode, which is a buffered input mode.
*/
void
enable_termraw()
{
struct termios raw;
/* Read the current terminal parameters for standard input. */
if (tcgetattr(STDIN_FILENO, &raw) == -1) {
die("tcgetattr while enabling raw mode");
}
/*
* Put the terminal into raw mode.
*/
cfmakeraw(&raw);
/*
* Set timeout for read(2).
*
* VMIN: what is the minimum number of bytes required for read
* to return?
*
* VTIME: max time before read(2) returns in hundreds of milli-
* seconds.
*/
raw.c_cc[VMIN] = 0;
raw.c_cc[VTIME] = 1;
/*
* Now write the terminal parameters to the current terminal,
* after flushing any waiting input out.
*/
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &raw) == -1) {
die("tcsetattr while enabling raw mode");
}
}
void
display_clear(struct abuf *ab)
{
if (ab == NULL) {
write(STDOUT_FILENO, ESCSEQ "2J", 4);
write(STDOUT_FILENO, ESCSEQ "H", 3);
} else {
ab_append(ab, ESCSEQ "2J", 4);
ab_append(ab, ESCSEQ "H", 3);
}
}
void
disable_termraw()
{
display_clear(NULL);
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &editor.entry_term) == -1) {
die("couldn't disable terminal raw mode");
}
}
void
setup_terminal()
{
if (tcgetattr(STDIN_FILENO, &editor.entry_term) == -1) {
die("can't snapshot terminal settings");
}
atexit(disable_termraw);
enable_termraw();
}
void
draw_rows(struct abuf *ab)
{
assert(editor.cols >= 0);
char buf[editor.cols];
int buflen, filerow, padding;
int y;
for (y = 0; y < editor.rows; y++) {
filerow = y + editor.rowoffs;
if (filerow >= editor.nrows) {
if ((editor.nrows == 0) && (y == editor.rows / 3)) {
buflen = snprintf(buf, sizeof(buf),
"ke v%s", KE_VERSION);
padding = (editor.rows - buflen) / 2;
if (padding) {
ab_append(ab, "|", 1);
padding--;
}
while (padding--) ab_append(ab, " ", 1);
ab_append(ab, buf, buflen);
} else {
ab_append(ab, "|", 1);
}
} else {
erow_update(&editor.row[filerow]);
buflen = editor.row[filerow].rsize - editor.coloffs;
if (buflen < 0) {
buflen = 0;
}
if (buflen > editor.cols) {
buflen = editor.cols;
}
ab_append(ab, editor.row[filerow].render+editor.coloffs,
buflen);
}
ab_append(ab, ESCSEQ "K", 3);
ab_append(ab, "\r\n", 2);
}
}
char
status_mode_char()
{
switch (editor.mode) {
case MODE_NORMAL:
return 'N';
case MODE_KCOMMAND:
return 'K';
case MODE_ESCAPE:
return 'E';
default:
return '?';
}
}
void
draw_status_bar(struct abuf *ab)
{
char status[editor.cols];
char rstatus[editor.cols];
int len, rlen;
len = snprintf(status, sizeof(status), "%c%cke: %.20s - %d lines",
status_mode_char(),
editor.dirty ? '!' : '-',
editor.filename ? editor.filename : "[no file]",
editor.nrows);
rlen = snprintf(rstatus, sizeof(rstatus), "L%d/%d C%d",
editor.cury+1, editor.nrows, editor.curx+1);
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(struct abuf *ab)
{
int 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()
{
editor.rx = 0;
if (editor.cury < editor.nrows) {
editor.rx = erow_render_to_cursor(
&editor.row[editor.cury],
editor.curx);
}
if (editor.cury < editor.rowoffs) {
editor.rowoffs = editor.cury;
}
if (editor.cury >= editor.rowoffs + editor.rows) {
editor.rowoffs = editor.cury - editor.rows + 1;
}
if (editor.rx < editor.coloffs) {
editor.coloffs = editor.rx;
}
if (editor.rx >= editor.coloffs + editor.cols) {
editor.coloffs = editor.rx - editor.cols + 1;
}
}
void
display_refresh()
{
char buf[32];
struct abuf ab = ABUF_INIT;
scroll();
ab_append(&ab, ESCSEQ "?25l", 6);
display_clear(&ab);
draw_rows(&ab);
draw_status_bar(&ab);
draw_message_line(&ab);
snprintf(buf, sizeof(buf), ESCSEQ "%d;%dH",
(editor.cury-editor.rowoffs)+1,
(editor.rx-editor.coloffs)+1);
ab_append(&ab, buf, strnlen(buf, 32));
/* ab_append(&ab, ESCSEQ "1;2H", 7); */
ab_append(&ab, ESCSEQ "?25h", 6);
write(STDOUT_FILENO, ab.b, ab.len);
ab_free(&ab);
}
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
loop()
{
int up = 1; /* update on the first runthrough */
while (1) {
if (up) display_refresh();
/*
* ke should only refresh the display if it has received keyboard
* input; if it has, drain all the inputs. This is useful for
* handling pastes without massive screen flicker.
*
*/
if ((up = process_keypress()) != 0) {
while (process_keypress()) ;
}
}
}
/*
* init_editor should set up the global editor struct.
*/
void
init_editor()
{
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 */
editor.curx = editor.cury = 0;
editor.rx = 0;
editor.nrows = 0;
editor.rowoffs = editor.coloffs = 0;
editor.row = NULL;
editor.msg[0] = '\0';
editor.msgtm = 0;
editor.dirty = 0;
}
int
main(int argc, char *argv[])
{
setup_terminal();
init_editor();
if (argc > 1) {
open_file(argv[1]);
}
editor_set_status("C-k q to exit / C-k d to dump core");
display_clear(NULL);
loop();
return 0;
}