/* hexedit.c - Hexadecimal file editor
*
* Copyright 2015 Rob Landley <rob@landley.net>
*
* No standard
USE_HEXEDIT(NEWTOY(hexedit, "<1>1r", TOYFLAG_USR|TOYFLAG_BIN|TOYFLAG_LOCALE))
config HEXEDIT
bool "hexedit"
default y
help
usage: hexedit FILENAME
Hexadecimal file editor.
-r Read only (display but don't edit)
*/
#define FOR_hexedit
#include "toys.h"
GLOBALS(
char *data;
long long len, base;
int numlen;
unsigned height;
)
static void esc(char *s)
{
printf("\033[%s", s);
}
static void jump(int x, int y)
{
char s[32];
sprintf(s, "%d;%dH", y+1, x+1);
esc(s);
}
static void fix_terminal(void)
{
set_terminal(1, 0, 0);
esc("?25h");
esc("0m");
jump(0, 999);
esc("K");
}
static void sigttyreset(int i)
{
fix_terminal();
// how do I re-raise the signal so it dies with right signal info for wait()?
_exit(127);
}
// Render all characters printable, using color to distinguish.
static void draw_char(char broiled)
{
if (broiled<32 || broiled>=127) {
if (broiled>127) {
esc("2m");
broiled &= 127;
}
if (broiled<32 || broiled==127) {
esc("7m");
if (broiled==127) broiled = 32;
else broiled += 64;
}
printf("%c", broiled);
esc("0m");
} else printf("%c", broiled);
}
static void draw_tail(void)
{
int i = 0, width = 0, w, len;
char *start = *toys.optargs, *end;
jump(0, TT.height);
esc("K");
// First time, make sure we fit in 71 chars (advancing start as necessary).
// Second time, print from start to end, escaping nonprintable chars.
for (i=0; i<2; i++) {
for (end = start; *end;) {
wchar_t wc;
len = mbrtowc(&wc, end, 99, 0);
if (len<0 || wc<32 || (w = wcwidth(wc))<0) {
len = w = 1;
if (i) draw_char(*end);
} else if (i) fwrite(end, len, 1, stdout);
end += len;
if (!i) {
width += w;
while (width > 71) {
len = mbrtowc(&wc, start, 99, 0);
if (len<0 || wc<32 || (w = wcwidth(wc))<0) len = w = 1;
width -= w;
start += len;
}
}
}
}
}
static void draw_line(long long yy)
{
int x, xx = 16;
yy = (TT.base+yy)*16;
if (yy+xx>=TT.len) xx = TT.len-yy;
if (yy<TT.len) {
printf("\r%0*llX ", TT.numlen, yy);
for (x=0; x<xx; x++) printf(" %02X", TT.data[yy+x]);
printf("%*s", 2+3*(16-xx), "");
for (x=0; x<xx; x++) draw_char(TT.data[yy+x]);
printf("%*s", 16-xx, "");
}
esc("K");
}
static void draw_page(void)
{
int y;
jump(0, 0);
for (y = 0; y<TT.height; y++) {
if (y) printf("\r\n");
draw_line(y);
}
draw_tail();
}
// side: 0 = editing left, 1 = editing right, 2 = clear, 3 = read only
static void highlight(int xx, int yy, int side)
{
char cc = TT.data[16*(TT.base+yy)+xx];
int i;
// Display cursor
jump(2+TT.numlen+3*xx, yy);
esc("0m");
if (side!=2) esc("7m");
if (side>1) printf("%02X", cc);
else for (i=0; i<2;) {
if (side==i) esc("32m");
printf("%X", (cc>>(4*(1&++i)))&15);
}
esc("0m");
jump(TT.numlen+17*3+xx, yy);
draw_char(cc);
}
#define KEY_UP 256
#define KEY_DOWN 257
#define KEY_RIGHT 258
#define KEY_LEFT 259
#define KEY_PGUP 260
#define KEY_PGDN 261
#define KEY_HOME 262
#define KEY_END 263
#define KEY_INSERT 264
void hexedit_main(void)
{
// up down right left pgup pgdn home end ins
char *keys[] = {"\033[A", "\033[B", "\033[C", "\033[D", "\033[5~", "\033[6~",
"\033OH", "\033OF", "\033[2~", 0};
long long pos;
int x, y, i, side = 0, key, ro = toys.optflags&FLAG_r,
fd = xopen(*toys.optargs, ro ? O_RDONLY : O_RDWR);
TT.height = 25;
terminal_size(0, &TT.height);
if (TT.height) TT.height--;
sigatexit(sigttyreset);
esc("0m");
esc("?25l");
fflush(0);
set_terminal(1, 1, 0);
if ((TT.len = fdlength(fd))<0) error_exit("bad length");
if (sizeof(long)==32 && TT.len>SIZE_MAX) TT.len = SIZE_MAX;
// count file length hex digits, rounded up to multiple of 4
for (pos = TT.len, TT.numlen = 0; pos; pos >>= 4, TT.numlen++);
TT.numlen += (4-TT.numlen)&3;
TT.data = mmap(0, TT.len, PROT_READ|(PROT_WRITE*!ro), MAP_SHARED, fd, 0);
draw_page();
y = x = 0;
for (;;) {
// Get position within file, trimming if we overshot end.
pos = 16*(TT.base+y)+x;
if (pos>=TT.len) {
pos = TT.len-1;
x = pos&15;
y = (pos/16)-TT.base;
}
// Display cursor
highlight(x, y, ro ? 3 : side);
xprintf("");
// Wait for next key
key = scan_key(toybuf, keys, 1);
// Exit for q, ctrl-c, ctrl-d, escape, or EOF
if (key==-1 || key==3 || key==4 || key==27 || key=='q') break;
highlight(x, y, 2);
if (key>='a' && key<='f') key-=32;
if (!ro && ((key>='0' && key<='9') || (key>='A' && key<='F'))) {
i = key - '0';
if (i>9) i -= 7;
TT.data[pos] &= 15<<(4*side);
TT.data[pos] |= i<<(4*!side);
highlight(x, y, ++side);
if (side==2) {
side = 0;
if (++pos<TT.len && ++x==16) {
x = 0;
if (++y == TT.height) {
--y;
goto down;
}
}
}
}
if (key>255) side = 0;
if (key==KEY_UP) {
if (--y<0) {
if (TT.base) {
TT.base--;
esc("1T");
draw_tail();
jump(0, 0);
draw_line(0);
}
y = 0;
}
} else if (key==KEY_DOWN) {
if (y == TT.height-1 && (pos|15)+1<TT.len) {
down:
TT.base++;
esc("1S");
jump(0, TT.height-1);
draw_line(TT.height-1);
draw_tail();
}
if (++y>=TT.height) y--;
} else if (key==KEY_RIGHT) {
if (x<15 && pos+1<TT.len) x++;
} else if (key==KEY_LEFT) {
if (x) x--;
} else if (key==KEY_PGUP) {
TT.base -= TT.height;
if (TT.base<0) TT.base = 0;
draw_page();
} else if (key==KEY_PGDN) {
TT.base += TT.height;
if ((TT.base*16)>=TT.len) TT.base=(TT.len-1)/16;
while ((TT.base+y)*16>=TT.len) y--;
if (16*(TT.base+y)+x>=TT.len) x = (TT.len-1)&15;
draw_page();
} else if (key==KEY_HOME) {
TT.base = 0;
x = 0;
draw_page();
} else if (key==KEY_END) {
TT.base=(TT.len-1)/16;
x = (TT.len-1)&15;
draw_page();
}
}
munmap(TT.data, TT.len);
close(fd);
fix_terminal();
}