more: by Tristan Schmelcher <tpkschme@engmail.uwaterloo.ca>:

- Fixed a number of deficiencies in the line wrapping.
- Fixed a bug where the page could scroll multiple times per keypress.
- Re-read terminal dimensions after user input, in case they
  resized the terminal while we were waiting.
- Added an 'R' key to print the rest of the file without prompting.
- Crudely support tabs in the line-wrapping code by converting
  them to 8 spaces.
This commit is contained in:
Denis Vlasenko 2007-08-15 20:42:52 +00:00
parent ab9c44b1a4
commit 033e592cbc

View File

@ -29,11 +29,11 @@ struct globals {
};
#define G (*(struct globals*)bb_common_bufsiz1)
//#define G (*ptr_to_globals)
#define INIT_G() ((void)0)
//#define INIT_G() PTR_TO_GLOBALS = xzalloc(sizeof(G))
#define initial_settings (G.initial_settings)
#define new_settings (G.new_settings )
#define cin_fileno (G.cin_fileno )
#define INIT_G() ((void)0)
//#define INIT_G() PTR_TO_GLOBALS = xzalloc(sizeof(G))
#define setTermSettings(fd, argp) tcsetattr(fd, TCSANOW, argp)
#define getTermSettings(fd, argp) tcgetattr(fd, argp)
@ -50,16 +50,20 @@ static void gotsig(int sig)
#define setTermSettings(fd, argp) ((void)0)
#endif /* FEATURE_USE_TERMIOS */
#define CONVERTED_TAB_SIZE 8
int more_main(int argc, char **argv);
int more_main(int argc, char **argv)
{
int c, lines, input = 0;
int please_display_more_prompt = 0;
int c = c; /* for gcc */
int lines;
int input = 0;
int spaces = 0;
int please_display_more_prompt;
struct stat st;
FILE *file;
FILE *cin;
int len, page_height;
int len;
int terminal_width;
int terminal_height;
@ -87,7 +91,6 @@ int more_main(int argc, char **argv)
signal(SIGQUIT, gotsig);
signal(SIGTERM, gotsig);
#endif
please_display_more_prompt = 2;
do {
file = stdin;
@ -99,19 +102,21 @@ int more_main(int argc, char **argv)
st.st_size = 0;
fstat(fileno(file), &st);
please_display_more_prompt &= ~1;
please_display_more_prompt = 0;
/* never returns w, h <= 1 */
get_terminal_width_height(fileno(cin), &terminal_width, &terminal_height);
terminal_width -= 1;
terminal_height -= 1;
len = 0;
lines = 0;
page_height = terminal_height;
while ((c = getc(file)) != EOF) {
if ((please_display_more_prompt & 3) == 3) {
while (spaces || (c = getc(file)) != EOF) {
int wrap;
if (spaces)
spaces--;
loop_top:
if (input != 'r' && please_display_more_prompt) {
len = printf("--More-- ");
if (/*file != stdin &&*/ st.st_size > 0) {
if (st.st_size > 0) {
len += printf("(%d%% of %"OFF_FMT"d bytes)",
(int) (ftello(file)*100 / st.st_size),
st.st_size);
@ -122,21 +127,42 @@ int more_main(int argc, char **argv)
* We've just displayed the "--More--" prompt, so now we need
* to get input from the user.
*/
for (;;) {
input = getc(cin);
input = tolower(input);
#if !ENABLE_FEATURE_USE_TERMIOS
printf("\033[A"); /* up cursor */
#endif
/* Erase the "More" message */
/* Erase the last message */
printf("\r%*s\r", len, "");
/* Due to various multibyte escape
* sequences, it's not ok to accept
* any input as a command to scroll
* the screen. We only allow known
* commands, else we show help msg. */
if (input == ' ' || input == '\n' || input == 'q' || input == 'r')
break;
len = printf("(Enter:next line Space:next page Q:quit R:show the rest)");
}
len = 0;
lines = 0;
/* Bottom line on page will become top line
* after one page forward. Thus -1: */
page_height = terminal_height - 1;
please_display_more_prompt &= ~1;
please_display_more_prompt = 0;
if (input == 'q')
goto end;
/* The user may have resized the terminal.
* Re-read the dimensions. */
get_terminal_width_height(cin_fileno, &terminal_width, &terminal_height);
terminal_height -= 1;
}
/* Crudely convert tabs into spaces, which are
* a bajillion times easier to deal with. */
if (c == '\t') {
spaces = CONVERTED_TAB_SIZE - 1;
c = ' ';
}
/*
@ -149,34 +175,24 @@ int more_main(int argc, char **argv)
* see if any characters have been hit in the _input_ stream. This
* allows the user to quit while in the middle of a file.
*/
if (c == '\n') {
/* increment by just one line if we are at
* the end of this line */
if (input == '\n')
please_display_more_prompt |= 1;
/* Adjust the terminal height for any overlap, so that
* no lines get lost off the top. */
if (len >= terminal_width) {
int quot, rem;
quot = len / terminal_width;
rem = len - (quot * terminal_width);
page_height -= (quot - 1);
if (rem)
page_height--;
}
if (++lines >= page_height) {
please_display_more_prompt |= 1;
}
wrap = (++len > terminal_width);
if (c == '\n' || wrap) {
/* Then outputting this character
* will move us to a new line. */
if (++lines >= terminal_height || input == '\n')
please_display_more_prompt = 1;
len = 0;
}
/*
* If we just read a newline from the file being 'mored' and any
* key other than a return is hit, scroll by one page
*/
putc(c, stdout);
/* My small mind cannot fathom tabs, backspaces,
* and UTF-8 */
len++;
if (c != '\n' && wrap) {
/* Then outputting this will also put a character on
* the beginning of that new line. Thus we first want to
* display the prompt (if any), so we skip the putchar()
* and go back to the top of the loop, without reading
* a new character. */
goto loop_top;
}
/* My small mind cannot fathom backspaces and UTF-8 */
putchar(c);
}
fclose(file);
fflush(stdout);