From 033e592cbc96c150c67ac9be7df65e314be5c8f8 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Wed, 15 Aug 2007 20:42:52 +0000 Subject: more: by Tristan Schmelcher : - 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. --- util-linux/more.c | 108 +++++++++++++++++++++++++++++++----------------------- 1 file changed, 62 insertions(+), 46 deletions(-) (limited to 'util-linux/more.c') diff --git a/util-linux/more.c b/util-linux/more.c index 4083d8eea..92ebdfea9 100644 --- a/util-linux/more.c +++ b/util-linux/more.c @@ -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); @@ -122,23 +127,44 @@ int more_main(int argc, char **argv) * We've just displayed the "--More--" prompt, so now we need * to get input from the user. */ - input = getc(cin); + for (;;) { + input = getc(cin); + input = tolower(input); #if !ENABLE_FEATURE_USE_TERMIOS - printf("\033[A"); /* up cursor */ + printf("\033[A"); /* up cursor */ #endif - /* Erase the "More" message */ - printf("\r%*s\r", len, ""); + /* 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 = ' '; + } + /* * There are two input streams to worry about here: * @@ -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); -- cgit v1.2.3