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/*
* view.c -- a silly little viewer program
*
* written by Eric S. Raymond <esr@snark.thyrsus.com> December 1994
* to test the scrolling code in ncurses.
*
* modified by Thomas Dickey <dickey@clark.net> July 1995 to demonstrate
* the use of 'resizeterm()', and May 2000 to illustrate wide-character
* handling.
*
* Takes a filename argument. It's a simple file-viewer with various
* scroll-up and scroll-down commands.
*
* n -- scroll one line forward
* p -- scroll one line back
*
* Either command accepts a numeric prefix interpreted as a repeat count.
* Thus, typing `5n' should scroll forward 5 lines in the file.
*
* The way you can tell this is working OK is that, in the trace file,
* there should be one scroll operation plus a small number of line
* updates, as opposed to a whole-page update. This means the physical
* scroll operation worked, and the refresh() code only had to do a
* partial repaint.
*
* $Id: view.c,v 1.60 2004/09/25 20:16:11 tom Exp $
*/
#include <time.h>
#include <test.priv.h>
#undef CTRL /* conflict on AIX 5.2 with <sys/ioctl.h> */
#if HAVE_TERMIOS_H
# include <termios.h>
#else
# include <sgtty.h>
#endif
#if !defined(sun) || !HAVE_TERMIOS_H
# if HAVE_SYS_IOCTL_H
# include <sys/ioctl.h>
# endif
#endif
#define my_pair 1
/* This is needed to compile 'struct winsize' */
#if NEED_PTEM_H
#include <sys/stream.h>
#include <sys/ptem.h>
#endif
static RETSIGTYPE finish(int sig) GCC_NORETURN;
static void show_all(const char *tag);
#if defined(SIGWINCH) && defined(TIOCGWINSZ) && HAVE_RESIZE_TERM
#define CAN_RESIZE 1
#else
#define CAN_RESIZE 0
#endif
#if CAN_RESIZE
static RETSIGTYPE adjust(int sig);
static int interrupted;
#endif
static bool waiting = FALSE;
static int shift = 0;
static bool try_color = FALSE;
static char *fname;
static NCURSES_CH_T **vec_lines;
static NCURSES_CH_T **lptr;
static int num_lines;
static void
usage(void)
{
static const char *msg[] =
{
"Usage: view [options] file"
,""
,"Options:"
," -c use color if terminal supports it"
," -i ignore INT, QUIT, TERM signals"
," -n NUM specify maximum number of lines (default 1000)"
#if defined(KEY_RESIZE)
," -r use old-style sigwinch handler rather than KEY_RESIZE"
#endif
#ifdef TRACE
," -t trace screen updates"
," -T NUM specify trace mask"
#endif
};
size_t n;
for (n = 0; n < SIZEOF(msg); n++)
fprintf(stderr, "%s\n", msg[n]);
ExitProgram(EXIT_FAILURE);
}
static int
ch_len(NCURSES_CH_T * src)
{
int result = 0;
#if USE_WIDEC_SUPPORT
#endif
#if USE_WIDEC_SUPPORT
while (getcchar(src++, NULL, NULL, NULL, NULL) > 0)
result++;
#else
while (*src++)
result++;
#endif
return result;
}
/*
* Allocate a string into an array of chtype's. If UTF-8 mode is
* active, translate the string accordingly.
*/
static NCURSES_CH_T *
ch_dup(char *src)
{
unsigned len = strlen(src);
NCURSES_CH_T *dst = typeMalloc(NCURSES_CH_T, len + 1);
unsigned j, k;
#if USE_WIDEC_SUPPORT
wchar_t wstr[CCHARW_MAX + 1];
wchar_t wch;
int l = 0;
mbstate_t state;
size_t rc;
int width;
#endif
#if USE_WIDEC_SUPPORT
memset(&state, 0, sizeof(state));
#endif
for (j = k = 0; j < len; j++) {
#if USE_WIDEC_SUPPORT
rc = mbrtowc(&wch, src + j, len - j, &state);
if (rc == (size_t) -1 || rc == (size_t) -2)
break;
j += rc - 1;
if ((width = wcwidth(wch)) < 0)
break;
if ((width > 0 && l > 0) || l == CCHARW_MAX) {
wstr[l] = L'\0';
l = 0;
if (setcchar(dst + k, wstr, 0, 0, NULL) != OK)
break;
++k;
}
if (width == 0 && l == 0)
wstr[l++] = L' ';
wstr[l++] = wch;
#else
dst[k++] = src[j];
#endif
}
#if USE_WIDEC_SUPPORT
if (l > 0) {
wstr[l] = L'\0';
if (setcchar(dst + k, wstr, 0, 0, NULL) == OK)
++k;
}
wstr[0] = L'\0';
setcchar(dst + k, wstr, 0, 0, NULL);
#else
dst[k] = 0;
#endif
return dst;
}
int
main(int argc, char *argv[])
{
int MAXLINES = 1000;
FILE *fp;
char buf[BUFSIZ];
int i;
int my_delay = 0;
NCURSES_CH_T **olptr;
int value = 0;
bool done = FALSE;
bool got_number = FALSE;
#if CAN_RESIZE
bool nonposix_resize = FALSE;
#endif
const char *my_label = "Input";
setlocale(LC_ALL, "");
#ifndef NCURSES_VERSION
/*
* We know ncurses will catch SIGINT if we don't establish our own handler.
* Other versions of curses may/may not catch it.
*/
(void) signal(SIGINT, finish); /* arrange interrupts to terminate */
#endif
while ((i = getopt(argc, argv, "cin:rtT:")) != EOF) {
switch (i) {
case 'c':
try_color = TRUE;
break;
case 'i':
signal(SIGINT, SIG_IGN);
signal(SIGQUIT, SIG_IGN);
signal(SIGTERM, SIG_IGN);
break;
case 'n':
if ((MAXLINES = atoi(optarg)) < 1)
usage();
break;
#if CAN_RESIZE
case 'r':
nonposix_resize = TRUE;
break;
#endif
#ifdef TRACE
case 'T':
trace(atoi(optarg));
break;
case 't':
trace(TRACE_CALLS);
break;
#endif
default:
usage();
}
}
if (optind + 1 != argc)
usage();
if ((vec_lines = typeMalloc(NCURSES_CH_T *, MAXLINES + 2)) == 0)
usage();
fname = argv[optind];
if ((fp = fopen(fname, "r")) == 0) {
perror(fname);
ExitProgram(EXIT_FAILURE);
}
#if CAN_RESIZE
if (nonposix_resize)
(void) signal(SIGWINCH, adjust); /* arrange interrupts to resize */
#endif
/* slurp the file */
for (lptr = &vec_lines[0]; (lptr - vec_lines) < MAXLINES; lptr++) {
char temp[BUFSIZ], *s, *d;
int col;
if (fgets(buf, sizeof(buf), fp) == 0)
break;
/* convert tabs so that shift will work properly */
for (s = buf, d = temp, col = 0; (*d = *s) != '\0'; s++) {
if (*d == '\n') {
*d = '\0';
break;
} else if (*d == '\t') {
col = (col | 7) + 1;
while ((d - temp) != col)
*d++ = ' ';
} else
#if USE_WIDEC_SUPPORT
col++, d++;
#else
if (isprint(UChar(*d))) {
col++;
d++;
} else {
sprintf(d, "\\%03o", UChar(*s));
d += strlen(d);
col = (d - temp);
}
#endif
}
*lptr = ch_dup(temp);
}
(void) fclose(fp);
num_lines = lptr - vec_lines;
(void) initscr(); /* initialize the curses library */
keypad(stdscr, TRUE); /* enable keyboard mapping */
(void) nonl(); /* tell curses not to do NL->CR/NL on output */
(void) cbreak(); /* take input chars one at a time, no wait for \n */
(void) noecho(); /* don't echo input */
nodelay(stdscr, TRUE);
idlok(stdscr, TRUE); /* allow use of insert/delete line */
if (try_color) {
if (has_colors()) {
start_color();
init_pair(my_pair, COLOR_WHITE, COLOR_BLUE);
bkgd(COLOR_PAIR(my_pair));
} else {
try_color = FALSE;
}
}
lptr = vec_lines;
while (!done) {
int n, c;
if (!got_number)
show_all(my_label);
n = 0;
for (;;) {
#if CAN_RESIZE
if (interrupted) {
adjust(0);
my_label = "interrupt";
}
#endif
waiting = TRUE;
c = getch();
waiting = FALSE;
if ((c < 127) && isdigit(c)) {
if (!got_number) {
mvprintw(0, 0, "Count: ");
clrtoeol();
}
addch(c);
value = 10 * value + (c - '0');
got_number = TRUE;
} else
break;
}
if (got_number && value) {
n = value;
} else {
n = 1;
}
if (c != ERR)
my_label = keyname(c);
switch (c) {
case KEY_DOWN:
case 'n':
olptr = lptr;
for (i = 0; i < n; i++)
if ((lptr - vec_lines) < (num_lines - LINES + 1))
lptr++;
else
break;
wscrl(stdscr, lptr - olptr);
break;
case KEY_UP:
case 'p':
olptr = lptr;
for (i = 0; i < n; i++)
if (lptr > vec_lines)
lptr--;
else
break;
wscrl(stdscr, lptr - olptr);
break;
case 'h':
case KEY_HOME:
lptr = vec_lines;
break;
case 'e':
case KEY_END:
if (num_lines > LINES)
lptr = vec_lines + num_lines - LINES + 1;
else
lptr = vec_lines;
break;
case 'r':
case KEY_RIGHT:
shift += n;
break;
case 'l':
case KEY_LEFT:
shift -= n;
if (shift < 0) {
shift = 0;
beep();
}
break;
case 'q':
done = TRUE;
break;
#ifdef KEY_RESIZE
case KEY_RESIZE: /* ignore this; ncurses will repaint */
break;
#endif
case 's':
if (got_number) {
halfdelay(my_delay = n);
} else {
nodelay(stdscr, FALSE);
my_delay = -1;
}
break;
case ' ':
nodelay(stdscr, TRUE);
my_delay = 0;
break;
case ERR:
if (!my_delay)
napms(50);
break;
default:
beep();
break;
}
if (c >= KEY_MIN || (c > 0 && !isdigit(c))) {
got_number = FALSE;
value = 0;
}
}
finish(0); /* we're done */
}
static RETSIGTYPE
finish(int sig)
{
endwin();
#if NO_LEAKS
if (vec_lines != 0) {
int n;
for (n = 0; n < num_lines; ++n) {
free(vec_lines[n]);
}
free(vec_lines);
}
#endif
ExitProgram(sig != 0 ? EXIT_FAILURE : EXIT_SUCCESS);
}
#if CAN_RESIZE
/*
* This uses functions that are "unsafe", but it seems to work on SunOS and
* Linux. Usually: the "unsafe" refers to the functions that POSIX lists
* which may be called from a signal handler. Those do not include buffered
* I/O, which is used for instance in wrefresh(). To be really portable, you
* should use the KEY_RESIZE return (which relies on ncurses' sigwinch
* handler).
*
* The 'wrefresh(curscr)' is needed to force the refresh to start from the top
* of the screen -- some xterms mangle the bitmap while resizing.
*/
static RETSIGTYPE
adjust(int sig)
{
if (waiting || sig == 0) {
struct winsize size;
if (ioctl(fileno(stdout), TIOCGWINSZ, &size) == 0) {
resize_term(size.ws_row, size.ws_col);
wrefresh(curscr); /* Linux needs this */
show_all(sig ? "SIGWINCH" : "interrupt");
}
interrupted = FALSE;
} else {
interrupted = TRUE;
}
(void) signal(SIGWINCH, adjust); /* some systems need this */
}
#endif /* CAN_RESIZE */
static void
show_all(const char *tag)
{
int i;
char temp[BUFSIZ];
NCURSES_CH_T *s;
time_t this_time;
#if CAN_RESIZE
sprintf(temp, "%s (%3dx%3d) col %d ", tag, LINES, COLS, shift);
i = strlen(temp);
sprintf(temp + i, "view %.*s", (int) (sizeof(temp) - 7 - i), fname);
#else
sprintf(temp, "view %.*s", (int) sizeof(temp) - 7, fname);
#endif
move(0, 0);
printw("%.*s", COLS, temp);
clrtoeol();
this_time = time((time_t *) 0);
strcpy(temp, ctime(&this_time));
if ((i = strlen(temp)) != 0) {
temp[--i] = 0;
if (move(0, COLS - i - 2) != ERR)
printw(" %s", temp);
}
scrollok(stdscr, FALSE); /* prevent screen from moving */
for (i = 1; i < LINES; i++) {
move(i, 0);
printw("%3ld:", (long) (lptr + i - vec_lines));
clrtoeol();
if ((s = lptr[i - 1]) != 0) {
int len = ch_len(s);
if (len > shift) {
#if USE_WIDEC_SUPPORT
add_wchstr(s + shift);
#else
addchstr(s + shift);
#endif
}
#if defined(NCURSES_VERSION) || defined(HAVE_WCHGAT)
if (try_color)
wchgat(stdscr, -1, A_NORMAL, my_pair, NULL);
#endif
}
}
setscrreg(1, LINES - 1);
scrollok(stdscr, TRUE);
refresh();
}
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