* Based on Russell Stuart's conspy.c
* http://ace-host.stuart.id.au/russell/files/conspy.c
*
- * Licensed under GPLv2 or later, see file License in this tarball for details.
- *
- * example : conspy num shared access to console num
- * or conspy -d num screenshot of console num
- * or conspy -cs num poor man's GNU screen like
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
+//config:config CONSPY
+//config: bool "conspy (10 kb)"
+//config: default y
+//config: select PLATFORM_LINUX
+//config: help
+//config: A text-mode VNC like program for Linux virtual terminals.
+//config: example: conspy NUM shared access to console num
+//config: or conspy -nd NUM screenshot of console num
+//config: or conspy -cs NUM poor man's GNU screen like
-//applet:IF_CONSPY(APPLET(conspy, _BB_DIR_BIN, _BB_SUID_DROP))
+//applet:IF_CONSPY(APPLET(conspy, BB_DIR_BIN, BB_SUID_DROP))
//kbuild:lib-$(CONFIG_CONSPY) += conspy.o
-//config:config CONSPY
-//config: bool "conspy"
-//config: default n
-//config: help
-//config: A text-mode VNC like program for Linux virtual terminals.
-//config: example : conspy num shared access to console num
-//config: or conspy -d num screenshot of console num
-//config: or conspy -cs num poor man's GNU screen like
-
//usage:#define conspy_trivial_usage
-//usage: "[-vcsndf] [-x ROW] [-y LINE] [CONSOLE_NO]"
+//usage: "[-vcsndfFQ] [-x COL] [-y LINE] [CONSOLE_NO]"
//usage:#define conspy_full_usage "\n\n"
//usage: "A text-mode VNC like program for Linux virtual consoles."
//usage: "\nTo exit, quickly press ESC 3 times."
//usage: "\n"
-//usage: "\nOptions:"
//usage: "\n -v Don't send keystrokes to the console"
-//usage: "\n -c Create missing devices in /dev"
+//usage: "\n -c Create missing /dev/{tty,vcsa}N"
//usage: "\n -s Open a SHELL session"
//usage: "\n -n Black & white"
//usage: "\n -d Dump console to stdout"
//usage: "\n -f Follow cursor"
-//usage: "\n -x ROW Starting row"
+//usage: "\n -F Assume console is on a framebuffer device"
+//usage: "\n -Q Disable exit on ESC-ESC-ESC"
+//usage: "\n -x COL Starting column"
//usage: "\n -y LINE Starting line"
#include "libbb.h"
+#include "common_bufsiz.h"
#include <sys/kd.h>
+#define ESC "\033"
+#define CURSOR_ON -1
+#define CURSOR_OFF 1
+
+#define DEV_TTY "/dev/tty"
+#define DEV_VCSA "/dev/vcsa"
+
struct screen_info {
- unsigned char lines, rows, cursor_x, cursor_y;
+ unsigned char lines, cols, cursor_x, cursor_y;
};
-#define CHAR(x) ((x)[0])
-#define ATTR(x) ((x)[1])
-#define NEXT(x) ((x)+=2)
-#define DATA(x) (* (short *) (x))
+#define CHAR(x) (*(uint8_t*)(x))
+#define ATTR(x) (((uint8_t*)(x))[1])
+#define NEXT(x) ((x) += 2)
+#define DATA(x) (*(uint16_t*)(x))
struct globals {
char* data;
int size;
int x, y;
int kbd_fd;
- unsigned width;
- unsigned height;
- uint8_t last_attr;
int ioerror_count;
int key_count;
int escape_count;
int nokeys;
int current;
- int vcsa_fd;
- struct screen_info info;
+ int first_line_offset;
+ int last_attr;
+ // cached local tty parameters
+ unsigned width;
+ unsigned height;
+ unsigned col;
+ unsigned line;
+ smallint curoff; // unknown:0 cursor on:-1 cursor off:1
+ char attrbuf[sizeof("0;1;5;30;40m")];
+ // remote console
+ struct screen_info remote;
+ // saved local tty terminfo
struct termios term_orig;
+ char vcsa_name[sizeof(DEV_VCSA "NN")];
};
#define G (*ptr_to_globals)
#define INIT_G() do { \
SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
+ G.width = G.height = UINT_MAX; \
+ G.last_attr--; \
} while (0)
enum {
FLAG_v, // view only
FLAG_c, // create device if need
+ FLAG_Q, // never exit
FLAG_s, // session
FLAG_n, // no colors
FLAG_d, // dump screen
FLAG_f, // follow cursor
+ FLAG_F, // framebuffer
};
#define FLAG(x) (1 << FLAG_##x)
#define BW (option_mask32 & FLAG(n))
+static void putcsi(const char *s)
+{
+ fputs(ESC"[", stdout);
+ fputs(s, stdout);
+}
+
+static void clrscr(void)
+{
+ // Home, clear till end of screen
+ putcsi("1;1H" ESC"[J");
+ G.col = G.line = 0;
+}
+
+static void set_cursor(int state)
+{
+ if (G.curoff != state) {
+ G.curoff = state;
+ putcsi("?25");
+ bb_putchar("h?l"[1 + state]);
+ }
+}
+
+static void gotoxy(int col, int line)
+{
+ if (G.col != col || G.line != line) {
+ G.col = col;
+ G.line = line;
+ printf(ESC"[%u;%uH", line + 1, col + 1);
+ }
+}
+
+static void cleanup(int code) NORETURN;
+static void cleanup(int code)
+{
+ set_cursor(CURSOR_ON);
+ tcsetattr(G.kbd_fd, TCSANOW, &G.term_orig);
+ if (ENABLE_FEATURE_CLEAN_UP) {
+ close(G.kbd_fd);
+ }
+ // Reset attributes
+ if (!BW)
+ putcsi("0m");
+ bb_putchar('\n');
+ if (code > EXIT_FAILURE)
+ kill_myself_with_sig(code);
+ exit(code);
+}
+
static void screen_read_close(void)
{
unsigned i, j;
- char *data = G.data + G.current;
-
- xread(G.vcsa_fd, data, G.size);
- G.last_attr = 0;
- for (i = 0; i < G.info.lines; i++) {
- for (j = 0; j < G.info.rows; j++, NEXT(data)) {
+ int vcsa_fd;
+ char *data;
+
+ // Close & re-open vcsa in case they have swapped virtual consoles
+ vcsa_fd = xopen(G.vcsa_name, O_RDONLY);
+ xread(vcsa_fd, &G.remote, 4);
+ i = G.remote.cols * 2;
+ G.first_line_offset = G.y * i;
+ i *= G.remote.lines;
+ if (G.data == NULL) {
+ G.size = i;
+ G.data = xzalloc(2 * i);
+ }
+ if (G.size != i) {
+ cleanup(EXIT_FAILURE);
+ }
+ data = G.data + G.current;
+ xread(vcsa_fd, data, G.size);
+ close(vcsa_fd);
+ for (i = 0; i < G.remote.lines; i++) {
+ for (j = 0; j < G.remote.cols; j++, NEXT(data)) {
unsigned x = j - G.x; // if will catch j < G.x too
unsigned y = i - G.y; // if will catch i < G.y too
- if (CHAR(data) < ' ')
- CHAR(data) = ' ';
if (y >= G.height || x >= G.width)
DATA(data) = 0;
+ else {
+ uint8_t ch = CHAR(data);
+ if (ch < ' ')
+ CHAR(data) = ch | 0x40;
+ else if (ch > 0x7e)
+ CHAR(data) = '?';
+ }
}
}
- close(G.vcsa_fd);
}
static void screen_char(char *data)
{
- uint8_t attr = ATTR(data);
+ if (!BW) {
+ uint8_t attr_diff;
+ uint8_t attr = ATTR(data);
- if (!BW && G.last_attr != attr) {
+ if (option_mask32 & FLAG(F)) {
+ attr >>= 1;
+ }
+ attr_diff = G.last_attr ^ attr;
+ if (attr_diff) {
// Attribute layout for VGA compatible text videobuffer:
// blinking text
// |red bkgd
// green text
// blue text
// text 8th bit
- // converting RGB color bit triad to BGR:
- static const char color[8] = "04261537";
-
- G.last_attr = attr;
- printf("\033[%c;4%c;3%cm",
- (attr & 8) ? '1' : '0', // bold text / reset all
- color[(attr >> 4) & 7], // bkgd color
- color[attr & 7] // text color
- );
+ // converting RGB color bit triad to BGR:
+ static const char color[8] = "04261537";
+ const uint8_t fg_mask = 0x07, bold_mask = 0x08;
+ const uint8_t bg_mask = 0x70, blink_mask = 0x80;
+ char *ptr;
+
+ ptr = G.attrbuf;
+
+ // (G.last_attr & ~attr) has 1 only where
+ // G.last_attr has 1 but attr has 0.
+ // Here we check whether we have transition
+ // bold->non-bold or blink->non-blink:
+ if (G.last_attr < 0 // initial value
+ || ((G.last_attr & ~attr) & (bold_mask | blink_mask)) != 0
+ ) {
+ *ptr++ = '0'; // "reset all attrs"
+ *ptr++ = ';';
+ // must set fg & bg, maybe need to set bold or blink:
+ attr_diff = attr | ~(bold_mask | blink_mask);
+ }
+ G.last_attr = attr;
+ if (attr_diff & bold_mask) {
+ *ptr++ = '1';
+ *ptr++ = ';';
+ }
+ if (attr_diff & blink_mask) {
+ *ptr++ = '5';
+ *ptr++ = ';';
+ }
+ if (attr_diff & fg_mask) {
+ *ptr++ = '3';
+ *ptr++ = color[attr & fg_mask];
+ *ptr++ = ';';
+ }
+ if (attr_diff & bg_mask) {
+ *ptr++ = '4';
+ *ptr++ = color[(attr & bg_mask) >> 4];
+ ptr++; // last attribute
+ }
+ if (ptr != G.attrbuf) {
+ ptr[-1] = 'm';
+ *ptr = '\0';
+ putcsi(G.attrbuf);
+ }
+ }
}
putchar(CHAR(data));
-}
-
-#define clrscr() printf("\033[1;1H" "\033[0J")
-#define curoff() printf("\033[?25l")
-
-static void curon(void)
-{
- printf("\033[?25h");
-}
-
-static void gotoxy(int row, int line)
-{
- printf("\033[%u;%uH", line + 1, row + 1);
+ G.col++;
}
static void screen_dump(void)
{
int linefeed_cnt;
- int line, row;
- int linecnt = G.info.lines - G.y;
- char *data = G.data + G.current + (2 * G.y * G.info.rows);
+ int line, col;
+ int linecnt = G.remote.lines - G.y;
+ char *data = G.data + G.current + G.first_line_offset;
linefeed_cnt = 0;
for (line = 0; line < linecnt && line < G.height; line++) {
int space_cnt = 0;
- for (row = 0; row < G.info.rows; row++, NEXT(data)) {
- unsigned tty_row = row - G.x; // if will catch row < G.x too
+ for (col = 0; col < G.remote.cols; col++, NEXT(data)) {
+ unsigned tty_col = col - G.x; // if will catch col < G.x too
- if (tty_row >= G.width)
+ if (tty_col >= G.width)
continue;
space_cnt++;
- if (BW && (CHAR(data) | ' ') == ' ')
+ if (BW && CHAR(data) == ' ')
continue;
while (linefeed_cnt != 0) {
- bb_putchar('\r');
+ //bb_putchar('\r'); - tty driver does it for us
bb_putchar('\n');
linefeed_cnt--;
}
static void curmove(void)
{
- unsigned cx = G.info.cursor_x - G.x;
- unsigned cy = G.info.cursor_y - G.y;
+ unsigned cx = G.remote.cursor_x - G.x;
+ unsigned cy = G.remote.cursor_y - G.y;
+ int cursor = CURSOR_OFF;
- if (cx >= G.width || cy >= G.height) {
- curoff();
- } else {
- curon();
+ if (cx < G.width && cy < G.height) {
gotoxy(cx, cy);
+ cursor = CURSOR_ON;
}
- fflush_all();
-}
-
-static void cleanup(int code)
-{
- curon();
- fflush_all();
- tcsetattr(G.kbd_fd, TCSANOW, &G.term_orig);
- if (ENABLE_FEATURE_CLEAN_UP) {
- free(ptr_to_globals);
- close(G.kbd_fd);
- }
- // Reset attributes
- if (!BW)
- printf("\033[0m");
- bb_putchar('\n');
- if (code > 1)
- kill_myself_with_sig(code); // does not return
- exit(code);
-}
-
-static void get_initial_data(const char* vcsa_name)
-{
- int size;
- G.vcsa_fd = xopen(vcsa_name, O_RDONLY);
- xread(G.vcsa_fd, &G.info, 4);
- G.size = size = G.info.rows * G.info.lines * 2;
- G.width = G.height = UINT_MAX;
- G.data = xzalloc(2 * size);
- screen_read_close();
+ set_cursor(cursor);
}
static void create_cdev_if_doesnt_exist(const char* name, dev_t dev)
static NOINLINE void start_shell_in_child(const char* tty_name)
{
- int pid = vfork();
- if (pid < 0) {
- bb_perror_msg_and_die("vfork");
- }
+ int pid = xvfork();
if (pid == 0) {
struct termios termchild;
- char *shell = getenv("SHELL");
+ const char *shell = get_shell_name();
- if (!shell)
- shell = (char *) DEFAULT_SHELL;
signal(SIGHUP, SIG_IGN);
// set tty as a controlling tty
setsid();
}
}
-int conspy_main(int argc UNUSED_PARAM, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int conspy_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int conspy_main(int argc UNUSED_PARAM, char **argv)
{
- char vcsa_name[sizeof("/dev/vcsa") + 2];
- char tty_name[sizeof("/dev/tty") + 2];
-#define keybuf bb_common_bufsiz1
- struct termios termbuf;
+ char tty_name[sizeof(DEV_TTY "NN")];
unsigned opts;
unsigned ttynum;
int poll_timeout_ms;
static const char getopt_longopts[] ALIGN1 =
"viewonly\0" No_argument "v"
"createdevice\0" No_argument "c"
+ "neverquit\0" No_argument "Q"
"session\0" No_argument "s"
"nocolors\0" No_argument "n"
"dump\0" No_argument "d"
"follow\0" No_argument "f"
+ "framebuffer\0" No_argument "F"
;
applet_long_options = getopt_longopts;
#endif
+#define keybuf bb_common_bufsiz1
+ setup_common_bufsiz();
+
INIT_G();
+ strcpy(G.vcsa_name, DEV_VCSA);
- opt_complementary = "x+:y+"; // numeric params
- opts = getopt32(argv, "vcsndfx:y:", &G.x, &G.y);
+ // numeric params
+ opts = getopt32(argv, "vcQsndfFx:+y:+", &G.x, &G.y);
argv += optind;
ttynum = 0;
if (argv[0]) {
ttynum = xatou_range(argv[0], 0, 63);
+ sprintf(G.vcsa_name + sizeof(DEV_VCSA)-1, "%u", ttynum);
}
- sprintf(vcsa_name, "/dev/vcsa%u", ttynum);
- sprintf(tty_name, "%s%u", "/dev/tty", ttynum);
+ sprintf(tty_name, "%s%u", DEV_TTY, ttynum);
if (opts & FLAG(c)) {
if ((opts & (FLAG(s)|FLAG(v))) != FLAG(v))
create_cdev_if_doesnt_exist(tty_name, makedev(4, ttynum));
- create_cdev_if_doesnt_exist(vcsa_name, makedev(7, 128 + ttynum));
+ create_cdev_if_doesnt_exist(G.vcsa_name, makedev(7, 128 + ttynum));
}
if ((opts & FLAG(s)) && ttynum) {
start_shell_in_child(tty_name);
}
- get_initial_data(vcsa_name);
- G.kbd_fd = xopen(CURRENT_TTY, O_RDONLY);
+ screen_read_close();
if (opts & FLAG(d)) {
screen_dump();
bb_putchar('\n');
- if (ENABLE_FEATURE_CLEAN_UP) {
- free(ptr_to_globals);
- close(G.kbd_fd);
- }
return 0;
}
bb_signals(BB_FATAL_SIGS, cleanup);
+
+ G.kbd_fd = xopen(CURRENT_TTY, O_RDONLY);
+
// All characters must be passed through to us unaltered
- tcgetattr(G.kbd_fd, &G.term_orig);
- termbuf = G.term_orig;
- termbuf.c_iflag &= ~(BRKINT|INLCR|ICRNL|IXON|IXOFF|IUCLC|IXANY|IMAXBEL);
- termbuf.c_oflag &= ~(OPOST);
- termbuf.c_lflag &= ~(ISIG|ICANON|ECHO);
- termbuf.c_cc[VMIN] = 1;
- termbuf.c_cc[VTIME] = 0;
- tcsetattr(G.kbd_fd, TCSANOW, &termbuf);
+ set_termios_to_raw(G.kbd_fd, &G.term_orig, 0
+ | TERMIOS_CLEAR_ISIG // no signals on ^C ^Z etc
+ | TERMIOS_RAW_INPUT // turn off all input conversions
+ );
+ //Note: termios.c_oflag &= ~(OPOST); - no, we still want \n -> \r\n
+
poll_timeout_ms = 250;
while (1) {
struct pollfd pfd;
int i, j;
char *data, *old;
- old = G.data + G.current;
- G.current = G.size - G.current;
- data = G.data + G.current;
-
- // Close & re-open vcsa in case they have
- // swapped virtual consoles
- G.vcsa_fd = xopen(vcsa_name, O_RDONLY);
- xread(G.vcsa_fd, &G.info, 4);
- if (G.size != (G.info.rows * G.info.lines * 2)) {
- cleanup(1);
- }
+ // in the first loop G.width = G.height = 0: refresh
i = G.width;
j = G.height;
get_terminal_width_height(G.kbd_fd, &G.width, &G.height);
- if ((option_mask32 & FLAG(f))) {
- int nx = G.info.cursor_x - G.width + 1;
- int ny = G.info.cursor_y - G.height + 1;
+ if (option_mask32 & FLAG(f)) {
+ int nx = G.remote.cursor_x - G.width + 1;
+ int ny = G.remote.cursor_y - G.height + 1;
- if (G.info.cursor_x < G.x) {
- G.x = G.info.cursor_x;
- i = 0; // force refresh
+ if (G.remote.cursor_x < G.x) {
+ G.x = G.remote.cursor_x;
+ i = 0; // force refresh
}
if (nx > G.x) {
G.x = nx;
- i = 0; // force refresh
+ i = 0; // force refresh
}
- if (G.info.cursor_y < G.y) {
- G.y = G.info.cursor_y;
- i = 0; // force refresh
+ if (G.remote.cursor_y < G.y) {
+ G.y = G.remote.cursor_y;
+ i = 0; // force refresh
}
if (ny > G.y) {
G.y = ny;
- i = 0; // force refresh
+ i = 0; // force refresh
}
}
// Scan console data and redraw our tty where needed
+ old = G.data + G.current;
+ G.current = G.size - G.current;
+ data = G.data + G.current;
screen_read_close();
if (i != G.width || j != G.height) {
clrscr();
screen_dump();
- }
- else for (i = 0; i < G.info.lines; i++) {
- char *last = last;
- char *first = NULL;
- int iy = i - G.y;
-
- if (iy >= (int) G.height)
- break;
- for (j = 0; j < G.info.rows; j++) {
- last = data;
- if (DATA(data) != DATA(old) && iy >= 0) {
- unsigned jx = j - G.x;
-
- last = NULL;
- if (first == NULL && jx < G.width) {
- first = data;
- gotoxy(jx, iy);
+ } else {
+ // For each remote line
+ old += G.first_line_offset;
+ data += G.first_line_offset;
+ for (i = G.y; i < G.remote.lines; i++) {
+ char *first = NULL; // first char which needs updating
+ char *last = last; // last char which needs updating
+ unsigned iy = i - G.y;
+
+ if (iy >= G.height)
+ break;
+ for (j = 0; j < G.remote.cols; j++, NEXT(old), NEXT(data)) {
+ unsigned jx = j - G.x; // if will catch j >= G.x too
+
+ if (jx < G.width && DATA(data) != DATA(old)) {
+ last = data;
+ if (!first) {
+ first = data;
+ gotoxy(jx, iy);
+ }
}
}
- NEXT(old);
- NEXT(data);
+ if (first) {
+ // Rewrite updated data on the local screen
+ for (; first <= last; NEXT(first))
+ screen_char(first);
+ }
}
- if (first == NULL)
- continue;
- if (last == NULL)
- last = data;
-
- // Write the data to the screen
- for (; first < last; NEXT(first))
- screen_char(first);
}
curmove();
// Wait for local user keypresses
+ fflush_all();
pfd.fd = G.kbd_fd;
pfd.events = POLLIN;
bytes_read = 0;
char *k;
case -1:
if (errno != EINTR)
- cleanup(1);
+ goto abort;
break;
case 0:
if (++G.nokeys >= 4)
default:
// Read the keys pressed
k = keybuf + G.key_count;
- bytes_read = read(G.kbd_fd, k, sizeof(keybuf) - G.key_count);
+ bytes_read = read(G.kbd_fd, k, COMMON_BUFSIZE - G.key_count);
if (bytes_read < 0)
- cleanup(1);
+ goto abort;
// Do exit processing
- for (i = 0; i < bytes_read; i++) {
- if (k[i] != '\033') G.escape_count = 0;
- else if (++G.escape_count >= 3)
- cleanup(0);
+ if (!(option_mask32 & FLAG(Q))) {
+ for (i = 0; i < bytes_read; i++) {
+ if (k[i] != '\033')
+ G.escape_count = -1;
+ if (++G.escape_count >= 3)
+ cleanup(EXIT_SUCCESS);
+ }
}
}
poll_timeout_ms = 250;
+ if (option_mask32 & FLAG(v)) continue;
// Insert all keys pressed into the virtual console's input
// buffer. Don't do this if the virtual console is in scan
// code mode - giving ASCII characters to a program expecting
// scan codes will confuse it.
- if (!(option_mask32 & FLAG(v)) && G.escape_count == 0) {
+ G.key_count += bytes_read;
+ if (G.escape_count == 0) {
int handle, result;
long kbd_mode;
- G.key_count += bytes_read;
handle = xopen(tty_name, O_WRONLY);
result = ioctl(handle, KDGKBMODE, &kbd_mode);
- if (result == -1)
- /* nothing */;
- else if (kbd_mode != K_XLATE && kbd_mode != K_UNICODE)
- G.key_count = 0; // scan code mode
- else {
- for (i = 0; i < G.key_count && result != -1; i++)
- result = ioctl(handle, TIOCSTI, keybuf + i);
- G.key_count -= i;
- if (G.key_count)
- memmove(keybuf, keybuf + i, G.key_count);
- // If there is an application on console which reacts
- // to keypresses, we need to make our first sleep
- // shorter to quickly redraw whatever it printed there.
- poll_timeout_ms = 20;
+ if (result >= 0) {
+ char *p = keybuf;
+
+ G.ioerror_count = 0;
+ if (kbd_mode != K_XLATE && kbd_mode != K_UNICODE) {
+ G.key_count = 0; // scan code mode
+ }
+ for (; G.key_count != 0; p++, G.key_count--) {
+ result = ioctl(handle, TIOCSTI, p);
+ if (result < 0) {
+ memmove(keybuf, p, G.key_count);
+ break;
+ }
+ // If there is an application on console which reacts
+ // to keypresses, we need to make our first sleep
+ // shorter to quickly redraw whatever it printed there.
+ poll_timeout_ms = 20;
+ }
+ }
+ // We sometimes get spurious IO errors on the TTY
+ // as programs close and re-open it
+ else if (errno != EIO || ++G.ioerror_count > 4) {
+ if (ENABLE_FEATURE_CLEAN_UP)
+ close(handle);
+ goto abort;
}
// Close & re-open tty in case they have
// swapped virtual consoles
close(handle);
-
- // We sometimes get spurious IO errors on the TTY
- // as programs close and re-open it
- if (result != -1)
- G.ioerror_count = 0;
- else if (errno != EIO || ++G.ioerror_count > 4)
- cleanup(1);
}
- }
+ } /* while (1) */
+ abort:
+ cleanup(EXIT_FAILURE);
}
projects / oweals / busybox.git / blobdiff