| /* vi: set sw=4 ts=4: */ |
| /* |
| * Mini less implementation for busybox |
| * |
| * Copyright (C) 2005 by Rob Sullivan <cogito.ergo.cogito@gmail.com> |
| * |
| * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
| */ |
| |
| /* |
| * TODO: |
| * - Add more regular expression support - search modifiers, certain matches, etc. |
| * - Add more complex bracket searching - currently, nested brackets are |
| * not considered. |
| * - Add support for "F" as an input. This causes less to act in |
| * a similar way to tail -f. |
| * - Allow horizontal scrolling. |
| * |
| * Notes: |
| * - the inp file pointer is used so that keyboard input works after |
| * redirected input has been read from stdin |
| */ |
| |
| //config:config LESS |
| //config: bool "less" |
| //config: default y |
| //config: help |
| //config: 'less' is a pager, meaning that it displays text files. It possesses |
| //config: a wide array of features, and is an improvement over 'more'. |
| //config: |
| //config:config FEATURE_LESS_MAXLINES |
| //config: int "Max number of input lines less will try to eat" |
| //config: default 9999999 |
| //config: depends on LESS |
| //config: |
| //config:config FEATURE_LESS_BRACKETS |
| //config: bool "Enable bracket searching" |
| //config: default y |
| //config: depends on LESS |
| //config: help |
| //config: This option adds the capability to search for matching left and right |
| //config: brackets, facilitating programming. |
| //config: |
| //config:config FEATURE_LESS_FLAGS |
| //config: bool "Enable extra flags" |
| //config: default y |
| //config: depends on LESS |
| //config: help |
| //config: The extra flags provided do the following: |
| //config: |
| //config: The -M flag enables a more sophisticated status line. |
| //config: The -m flag enables a simpler status line with a percentage. |
| //config: |
| //config:config FEATURE_LESS_MARKS |
| //config: bool "Enable marks" |
| //config: default y |
| //config: depends on LESS |
| //config: help |
| //config: Marks enable positions in a file to be stored for easy reference. |
| //config: |
| //config:config FEATURE_LESS_REGEXP |
| //config: bool "Enable regular expressions" |
| //config: default y |
| //config: depends on LESS |
| //config: help |
| //config: Enable regular expressions, allowing complex file searches. |
| //config: |
| //config:config FEATURE_LESS_WINCH |
| //config: bool "Enable automatic resizing on window size changes" |
| //config: default y |
| //config: depends on LESS |
| //config: help |
| //config: Makes less track window size changes. |
| //config: |
| //config:config FEATURE_LESS_ASK_TERMINAL |
| //config: bool "Use 'tell me cursor position' ESC sequence to measure window" |
| //config: default y |
| //config: depends on FEATURE_LESS_WINCH |
| //config: help |
| //config: Makes less track window size changes. |
| //config: If terminal size can't be retrieved and $LINES/$COLUMNS are not set, |
| //config: this option makes less perform a last-ditch effort to find it: |
| //config: position cursor to 999,999 and ask terminal to report real |
| //config: cursor position using "ESC [ 6 n" escape sequence, then read stdin. |
| //config: |
| //config: This is not clean but helps a lot on serial lines and such. |
| //config: |
| //config:config FEATURE_LESS_DASHCMD |
| //config: bool "Enable flag changes ('-' command)" |
| //config: default y |
| //config: depends on LESS |
| //config: help |
| //config: This enables the ability to change command-line flags within |
| //config: less itself ('-' keyboard command). |
| //config: |
| //config:config FEATURE_LESS_LINENUMS |
| //config: bool "Enable dynamic switching of line numbers" |
| //config: default y |
| //config: depends on FEATURE_LESS_DASHCMD |
| //config: help |
| //config: Enables "-N" command. |
| |
| //usage:#define less_trivial_usage |
| //usage: "[-EMNmh~I?] [FILE]..." |
| //usage:#define less_full_usage "\n\n" |
| //usage: "View FILE (or stdin) one screenful at a time\n" |
| //usage: "\n -E Quit once the end of a file is reached" |
| //usage: "\n -M,-m Display status line with line numbers" |
| //usage: "\n and percentage through the file" |
| //usage: "\n -N Prefix line number to each line" |
| //usage: "\n -I Ignore case in all searches" |
| //usage: "\n -~ Suppress ~s displayed past the end of the file" |
| |
| #include <sched.h> /* sched_yield() */ |
| |
| #include "libbb.h" |
| #if ENABLE_FEATURE_LESS_REGEXP |
| #include "xregex.h" |
| #endif |
| |
| |
| #define ESC "\033" |
| /* The escape codes for highlighted and normal text */ |
| #define HIGHLIGHT ESC"[7m" |
| #define NORMAL ESC"[0m" |
| /* The escape code to home and clear to the end of screen */ |
| #define CLEAR ESC"[H\033[J" |
| /* The escape code to clear to the end of line */ |
| #define CLEAR_2_EOL ESC"[K" |
| |
| enum { |
| /* Absolute max of lines eaten */ |
| MAXLINES = CONFIG_FEATURE_LESS_MAXLINES, |
| /* This many "after the end" lines we will show (at max) */ |
| TILDES = 1, |
| }; |
| |
| /* Command line options */ |
| enum { |
| FLAG_E = 1 << 0, |
| FLAG_M = 1 << 1, |
| FLAG_m = 1 << 2, |
| FLAG_N = 1 << 3, |
| FLAG_TILDE = 1 << 4, |
| FLAG_I = 1 << 5, |
| FLAG_S = (1 << 6) * ENABLE_FEATURE_LESS_DASHCMD, |
| /* hijack command line options variable for internal state vars */ |
| LESS_STATE_MATCH_BACKWARDS = 1 << 15, |
| }; |
| |
| #if !ENABLE_FEATURE_LESS_REGEXP |
| enum { pattern_valid = 0 }; |
| #endif |
| |
| struct globals { |
| int cur_fline; /* signed */ |
| int kbd_fd; /* fd to get input from */ |
| int less_gets_pos; |
| /* last position in last line, taking into account tabs */ |
| size_t last_line_pos; |
| unsigned max_fline; |
| unsigned max_lineno; /* this one tracks linewrap */ |
| unsigned max_displayed_line; |
| unsigned width; |
| #if ENABLE_FEATURE_LESS_WINCH |
| unsigned winch_counter; |
| #endif |
| ssize_t eof_error; /* eof if 0, error if < 0 */ |
| ssize_t readpos; |
| ssize_t readeof; /* must be signed */ |
| const char **buffer; |
| const char **flines; |
| const char *empty_line_marker; |
| unsigned num_files; |
| unsigned current_file; |
| char *filename; |
| char **files; |
| #if ENABLE_FEATURE_LESS_MARKS |
| unsigned num_marks; |
| unsigned mark_lines[15][2]; |
| #endif |
| #if ENABLE_FEATURE_LESS_REGEXP |
| unsigned *match_lines; |
| int match_pos; /* signed! */ |
| int wanted_match; /* signed! */ |
| int num_matches; |
| regex_t pattern; |
| smallint pattern_valid; |
| #endif |
| #if ENABLE_FEATURE_LESS_ASK_TERMINAL |
| smallint winsize_err; |
| #endif |
| smallint terminated; |
| struct termios term_orig, term_less; |
| char kbd_input[KEYCODE_BUFFER_SIZE]; |
| }; |
| #define G (*ptr_to_globals) |
| #define cur_fline (G.cur_fline ) |
| #define kbd_fd (G.kbd_fd ) |
| #define less_gets_pos (G.less_gets_pos ) |
| #define last_line_pos (G.last_line_pos ) |
| #define max_fline (G.max_fline ) |
| #define max_lineno (G.max_lineno ) |
| #define max_displayed_line (G.max_displayed_line) |
| #define width (G.width ) |
| #define winch_counter (G.winch_counter ) |
| /* This one is 100% not cached by compiler on read access */ |
| #define WINCH_COUNTER (*(volatile unsigned *)&winch_counter) |
| #define eof_error (G.eof_error ) |
| #define readpos (G.readpos ) |
| #define readeof (G.readeof ) |
| #define buffer (G.buffer ) |
| #define flines (G.flines ) |
| #define empty_line_marker (G.empty_line_marker ) |
| #define num_files (G.num_files ) |
| #define current_file (G.current_file ) |
| #define filename (G.filename ) |
| #define files (G.files ) |
| #define num_marks (G.num_marks ) |
| #define mark_lines (G.mark_lines ) |
| #if ENABLE_FEATURE_LESS_REGEXP |
| #define match_lines (G.match_lines ) |
| #define match_pos (G.match_pos ) |
| #define num_matches (G.num_matches ) |
| #define wanted_match (G.wanted_match ) |
| #define pattern (G.pattern ) |
| #define pattern_valid (G.pattern_valid ) |
| #endif |
| #define terminated (G.terminated ) |
| #define term_orig (G.term_orig ) |
| #define term_less (G.term_less ) |
| #define kbd_input (G.kbd_input ) |
| #define INIT_G() do { \ |
| SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \ |
| less_gets_pos = -1; \ |
| empty_line_marker = "~"; \ |
| num_files = 1; \ |
| current_file = 1; \ |
| eof_error = 1; \ |
| terminated = 1; \ |
| IF_FEATURE_LESS_REGEXP(wanted_match = -1;) \ |
| } while (0) |
| |
| /* flines[] are lines read from stdin, each in malloc'ed buffer. |
| * Line numbers are stored as uint32_t prepended to each line. |
| * Pointer is adjusted so that flines[i] points directly past |
| * line number. Accesor: */ |
| #define MEMPTR(p) ((char*)(p) - 4) |
| #define LINENO(p) (*(uint32_t*)((p) - 4)) |
| |
| |
| /* Reset terminal input to normal */ |
| static void set_tty_cooked(void) |
| { |
| fflush_all(); |
| tcsetattr(kbd_fd, TCSANOW, &term_orig); |
| } |
| |
| /* Move the cursor to a position (x,y), where (0,0) is the |
| top-left corner of the console */ |
| static void move_cursor(int line, int row) |
| { |
| printf(ESC"[%u;%uH", line, row); |
| } |
| |
| static void clear_line(void) |
| { |
| printf(ESC"[%u;0H" CLEAR_2_EOL, max_displayed_line + 2); |
| } |
| |
| static void print_hilite(const char *str) |
| { |
| printf(HIGHLIGHT"%s"NORMAL, str); |
| } |
| |
| static void print_statusline(const char *str) |
| { |
| clear_line(); |
| printf(HIGHLIGHT"%.*s"NORMAL, width - 1, str); |
| } |
| |
| /* Exit the program gracefully */ |
| static void less_exit(int code) |
| { |
| set_tty_cooked(); |
| clear_line(); |
| if (code < 0) |
| kill_myself_with_sig(- code); /* does not return */ |
| exit(code); |
| } |
| |
| #if (ENABLE_FEATURE_LESS_DASHCMD && ENABLE_FEATURE_LESS_LINENUMS) \ |
| || ENABLE_FEATURE_LESS_WINCH |
| static void re_wrap(void) |
| { |
| int w = width; |
| int new_line_pos; |
| int src_idx; |
| int dst_idx; |
| int new_cur_fline = 0; |
| uint32_t lineno; |
| char linebuf[w + 1]; |
| const char **old_flines = flines; |
| const char *s; |
| char **new_flines = NULL; |
| char *d; |
| |
| if (option_mask32 & FLAG_N) |
| w -= 8; |
| |
| src_idx = 0; |
| dst_idx = 0; |
| s = old_flines[0]; |
| lineno = LINENO(s); |
| d = linebuf; |
| new_line_pos = 0; |
| while (1) { |
| *d = *s; |
| if (*d != '\0') { |
| new_line_pos++; |
| if (*d == '\t') /* tab */ |
| new_line_pos += 7; |
| s++; |
| d++; |
| if (new_line_pos >= w) { |
| int sz; |
| /* new line is full, create next one */ |
| *d = '\0'; |
| next_new: |
| sz = (d - linebuf) + 1; /* + 1: NUL */ |
| d = ((char*)xmalloc(sz + 4)) + 4; |
| LINENO(d) = lineno; |
| memcpy(d, linebuf, sz); |
| new_flines = xrealloc_vector(new_flines, 8, dst_idx); |
| new_flines[dst_idx] = d; |
| dst_idx++; |
| if (new_line_pos < w) { |
| /* if we came here thru "goto next_new" */ |
| if (src_idx > max_fline) |
| break; |
| lineno = LINENO(s); |
| } |
| d = linebuf; |
| new_line_pos = 0; |
| } |
| continue; |
| } |
| /* *d == NUL: old line ended, go to next old one */ |
| free(MEMPTR(old_flines[src_idx])); |
| /* btw, convert cur_fline... */ |
| if (cur_fline == src_idx) |
| new_cur_fline = dst_idx; |
| src_idx++; |
| /* no more lines? finish last new line (and exit the loop) */ |
| if (src_idx > max_fline) |
| goto next_new; |
| s = old_flines[src_idx]; |
| if (lineno != LINENO(s)) { |
| /* this is not a continuation line! |
| * create next _new_ line too */ |
| goto next_new; |
| } |
| } |
| |
| free(old_flines); |
| flines = (const char **)new_flines; |
| |
| max_fline = dst_idx - 1; |
| last_line_pos = new_line_pos; |
| cur_fline = new_cur_fline; |
| /* max_lineno is screen-size independent */ |
| #if ENABLE_FEATURE_LESS_REGEXP |
| pattern_valid = 0; |
| #endif |
| } |
| #endif |
| |
| #if ENABLE_FEATURE_LESS_REGEXP |
| static void fill_match_lines(unsigned pos); |
| #else |
| #define fill_match_lines(pos) ((void)0) |
| #endif |
| |
| /* Devilishly complex routine. |
| * |
| * Has to deal with EOF and EPIPE on input, |
| * with line wrapping, with last line not ending in '\n' |
| * (possibly not ending YET!), with backspace and tabs. |
| * It reads input again if last time we got an EOF (thus supporting |
| * growing files) or EPIPE (watching output of slow process like make). |
| * |
| * Variables used: |
| * flines[] - array of lines already read. Linewrap may cause |
| * one source file line to occupy several flines[n]. |
| * flines[max_fline] - last line, possibly incomplete. |
| * terminated - 1 if flines[max_fline] is 'terminated' |
| * (if there was '\n' [which isn't stored itself, we just remember |
| * that it was seen]) |
| * max_lineno - last line's number, this one doesn't increment |
| * on line wrap, only on "real" new lines. |
| * readbuf[0..readeof-1] - small preliminary buffer. |
| * readbuf[readpos] - next character to add to current line. |
| * last_line_pos - screen line position of next char to be read |
| * (takes into account tabs and backspaces) |
| * eof_error - < 0 error, == 0 EOF, > 0 not EOF/error |
| */ |
| static void read_lines(void) |
| { |
| #define readbuf bb_common_bufsiz1 |
| char *current_line, *p; |
| int w = width; |
| char last_terminated = terminated; |
| #if ENABLE_FEATURE_LESS_REGEXP |
| unsigned old_max_fline = max_fline; |
| time_t last_time = 0; |
| unsigned seconds_p1 = 3; /* seconds_to_loop + 1 */ |
| #endif |
| |
| if (option_mask32 & FLAG_N) |
| w -= 8; |
| |
| IF_FEATURE_LESS_REGEXP(again0:) |
| |
| p = current_line = ((char*)xmalloc(w + 4)) + 4; |
| max_fline += last_terminated; |
| if (!last_terminated) { |
| const char *cp = flines[max_fline]; |
| strcpy(p, cp); |
| p += strlen(current_line); |
| free(MEMPTR(flines[max_fline])); |
| /* last_line_pos is still valid from previous read_lines() */ |
| } else { |
| last_line_pos = 0; |
| } |
| |
| while (1) { /* read lines until we reach cur_fline or wanted_match */ |
| *p = '\0'; |
| terminated = 0; |
| while (1) { /* read chars until we have a line */ |
| char c; |
| /* if no unprocessed chars left, eat more */ |
| if (readpos >= readeof) { |
| ndelay_on(0); |
| eof_error = safe_read(STDIN_FILENO, readbuf, sizeof(readbuf)); |
| ndelay_off(0); |
| readpos = 0; |
| readeof = eof_error; |
| if (eof_error <= 0) |
| goto reached_eof; |
| } |
| c = readbuf[readpos]; |
| /* backspace? [needed for manpages] */ |
| /* <tab><bs> is (a) insane and */ |
| /* (b) harder to do correctly, so we refuse to do it */ |
| if (c == '\x8' && last_line_pos && p[-1] != '\t') { |
| readpos++; /* eat it */ |
| last_line_pos--; |
| /* was buggy (p could end up <= current_line)... */ |
| *--p = '\0'; |
| continue; |
| } |
| { |
| size_t new_last_line_pos = last_line_pos + 1; |
| if (c == '\t') { |
| new_last_line_pos += 7; |
| new_last_line_pos &= (~7); |
| } |
| if ((int)new_last_line_pos >= w) |
| break; |
| last_line_pos = new_last_line_pos; |
| } |
| /* ok, we will eat this char */ |
| readpos++; |
| if (c == '\n') { |
| terminated = 1; |
| last_line_pos = 0; |
| break; |
| } |
| /* NUL is substituted by '\n'! */ |
| if (c == '\0') c = '\n'; |
| *p++ = c; |
| *p = '\0'; |
| } /* end of "read chars until we have a line" loop */ |
| /* Corner case: linewrap with only "" wrapping to next line */ |
| /* Looks ugly on screen, so we do not store this empty line */ |
| if (!last_terminated && !current_line[0]) { |
| last_terminated = 1; |
| max_lineno++; |
| continue; |
| } |
| reached_eof: |
| last_terminated = terminated; |
| flines = xrealloc_vector(flines, 8, max_fline); |
| |
| flines[max_fline] = (char*)xrealloc(MEMPTR(current_line), strlen(current_line) + 1 + 4) + 4; |
| LINENO(flines[max_fline]) = max_lineno; |
| if (terminated) |
| max_lineno++; |
| |
| if (max_fline >= MAXLINES) { |
| eof_error = 0; /* Pretend we saw EOF */ |
| break; |
| } |
| if (!(option_mask32 & FLAG_S) |
| ? (max_fline > cur_fline + max_displayed_line) |
| : (max_fline >= cur_fline |
| && max_lineno > LINENO(flines[cur_fline]) + max_displayed_line) |
| ) { |
| #if !ENABLE_FEATURE_LESS_REGEXP |
| break; |
| #else |
| if (wanted_match >= num_matches) { /* goto_match called us */ |
| fill_match_lines(old_max_fline); |
| old_max_fline = max_fline; |
| } |
| if (wanted_match < num_matches) |
| break; |
| #endif |
| } |
| if (eof_error <= 0) { |
| if (eof_error < 0) { |
| if (errno == EAGAIN) { |
| /* not yet eof or error, reset flag (or else |
| * we will hog CPU - select() will return |
| * immediately */ |
| eof_error = 1; |
| } else { |
| print_statusline(bb_msg_read_error); |
| } |
| } |
| #if !ENABLE_FEATURE_LESS_REGEXP |
| break; |
| #else |
| if (wanted_match < num_matches) { |
| break; |
| } else { /* goto_match called us */ |
| time_t t = time(NULL); |
| if (t != last_time) { |
| last_time = t; |
| if (--seconds_p1 == 0) |
| break; |
| } |
| sched_yield(); |
| goto again0; /* go loop again (max 2 seconds) */ |
| } |
| #endif |
| } |
| max_fline++; |
| current_line = ((char*)xmalloc(w + 4)) + 4; |
| p = current_line; |
| last_line_pos = 0; |
| } /* end of "read lines until we reach cur_fline" loop */ |
| fill_match_lines(old_max_fline); |
| #if ENABLE_FEATURE_LESS_REGEXP |
| /* prevent us from being stuck in search for a match */ |
| wanted_match = -1; |
| #endif |
| #undef readbuf |
| } |
| |
| #if ENABLE_FEATURE_LESS_FLAGS |
| /* Interestingly, writing calc_percent as a function saves around 32 bytes |
| * on my build. */ |
| static int calc_percent(void) |
| { |
| unsigned p = (100 * (cur_fline+max_displayed_line+1) + max_fline/2) / (max_fline+1); |
| return p <= 100 ? p : 100; |
| } |
| |
| /* Print a status line if -M was specified */ |
| static void m_status_print(void) |
| { |
| int percentage; |
| |
| if (less_gets_pos >= 0) /* don't touch statusline while input is done! */ |
| return; |
| |
| clear_line(); |
| printf(HIGHLIGHT"%s", filename); |
| if (num_files > 1) |
| printf(" (file %i of %i)", current_file, num_files); |
| printf(" lines %i-%i/%i ", |
| cur_fline + 1, cur_fline + max_displayed_line + 1, |
| max_fline + 1); |
| if (cur_fline >= (int)(max_fline - max_displayed_line)) { |
| printf("(END)"NORMAL); |
| if (num_files > 1 && current_file != num_files) |
| printf(HIGHLIGHT" - next: %s"NORMAL, files[current_file]); |
| return; |
| } |
| percentage = calc_percent(); |
| printf("%i%%"NORMAL, percentage); |
| } |
| #endif |
| |
| /* Print the status line */ |
| static void status_print(void) |
| { |
| const char *p; |
| |
| if (less_gets_pos >= 0) /* don't touch statusline while input is done! */ |
| return; |
| |
| /* Change the status if flags have been set */ |
| #if ENABLE_FEATURE_LESS_FLAGS |
| if (option_mask32 & (FLAG_M|FLAG_m)) { |
| m_status_print(); |
| return; |
| } |
| /* No flags set */ |
| #endif |
| |
| clear_line(); |
| if (cur_fline && cur_fline < (int)(max_fline - max_displayed_line)) { |
| bb_putchar(':'); |
| return; |
| } |
| p = "(END)"; |
| if (!cur_fline) |
| p = filename; |
| if (num_files > 1) { |
| printf(HIGHLIGHT"%s (file %i of %i)"NORMAL, |
| p, current_file, num_files); |
| return; |
| } |
| print_hilite(p); |
| } |
| |
| static void cap_cur_fline(int nlines) |
| { |
| int diff; |
| if (cur_fline < 0) |
| cur_fline = 0; |
| if (cur_fline + max_displayed_line > max_fline + TILDES) { |
| cur_fline -= nlines; |
| if (cur_fline < 0) |
| cur_fline = 0; |
| diff = max_fline - (cur_fline + max_displayed_line) + TILDES; |
| /* As the number of lines requested was too large, we just move |
| * to the end of the file */ |
| if (diff > 0) |
| cur_fline += diff; |
| } |
| } |
| |
| static const char controls[] ALIGN1 = |
| /* NUL: never encountered; TAB: not converted */ |
| /**/"\x01\x02\x03\x04\x05\x06\x07\x08" "\x0a\x0b\x0c\x0d\x0e\x0f" |
| "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f" |
| "\x7f\x9b"; /* DEL and infamous Meta-ESC :( */ |
| static const char ctrlconv[] ALIGN1 = |
| /* why 40 instead of 4a below? - it is a replacement for '\n'. |
| * '\n' is a former NUL - we subst it with @, not J */ |
| "\x40\x41\x42\x43\x44\x45\x46\x47\x48\x49\x40\x4b\x4c\x4d\x4e\x4f" |
| "\x50\x51\x52\x53\x54\x55\x56\x57\x58\x59\x5a\x5b\x5c\x5d\x5e\x5f"; |
| |
| static void lineno_str(char *nbuf9, const char *line) |
| { |
| nbuf9[0] = '\0'; |
| if (option_mask32 & FLAG_N) { |
| const char *fmt; |
| unsigned n; |
| |
| if (line == empty_line_marker) { |
| memset(nbuf9, ' ', 8); |
| nbuf9[8] = '\0'; |
| return; |
| } |
| /* Width of 7 preserves tab spacing in the text */ |
| fmt = "%7u "; |
| n = LINENO(line) + 1; |
| if (n > 9999999) { |
| n %= 10000000; |
| fmt = "%07u "; |
| } |
| sprintf(nbuf9, fmt, n); |
| } |
| } |
| |
| |
| #if ENABLE_FEATURE_LESS_REGEXP |
| static void print_found(const char *line) |
| { |
| int match_status; |
| int eflags; |
| char *growline; |
| regmatch_t match_structs; |
| |
| char buf[width]; |
| char nbuf9[9]; |
| const char *str = line; |
| char *p = buf; |
| size_t n; |
| |
| while (*str) { |
| n = strcspn(str, controls); |
| if (n) { |
| if (!str[n]) break; |
| memcpy(p, str, n); |
| p += n; |
| str += n; |
| } |
| n = strspn(str, controls); |
| memset(p, '.', n); |
| p += n; |
| str += n; |
| } |
| strcpy(p, str); |
| |
| /* buf[] holds quarantined version of str */ |
| |
| /* Each part of the line that matches has the HIGHLIGHT |
| and NORMAL escape sequences placed around it. |
| NB: we regex against line, but insert text |
| from quarantined copy (buf[]) */ |
| str = buf; |
| growline = NULL; |
| eflags = 0; |
| goto start; |
| |
| while (match_status == 0) { |
| char *new = xasprintf("%s%.*s"HIGHLIGHT"%.*s"NORMAL, |
| growline ? growline : "", |
| (int)match_structs.rm_so, str, |
| (int)(match_structs.rm_eo - match_structs.rm_so), |
| str + match_structs.rm_so); |
| free(growline); |
| growline = new; |
| str += match_structs.rm_eo; |
| line += match_structs.rm_eo; |
| eflags = REG_NOTBOL; |
| start: |
| /* Most of the time doesn't find the regex, optimize for that */ |
| match_status = regexec(&pattern, line, 1, &match_structs, eflags); |
| /* if even "" matches, treat it as "not a match" */ |
| if (match_structs.rm_so >= match_structs.rm_eo) |
| match_status = 1; |
| } |
| |
| lineno_str(nbuf9, line); |
| if (!growline) { |
| printf(CLEAR_2_EOL"%s%s\n", nbuf9, str); |
| return; |
| } |
| printf(CLEAR_2_EOL"%s%s%s\n", nbuf9, growline, str); |
| free(growline); |
| } |
| #else |
| void print_found(const char *line); |
| #endif |
| |
| static void print_ascii(const char *str) |
| { |
| char buf[width]; |
| char nbuf9[9]; |
| char *p; |
| size_t n; |
| |
| lineno_str(nbuf9, str); |
| printf(CLEAR_2_EOL"%s", nbuf9); |
| |
| while (*str) { |
| n = strcspn(str, controls); |
| if (n) { |
| if (!str[n]) break; |
| printf("%.*s", (int) n, str); |
| str += n; |
| } |
| n = strspn(str, controls); |
| p = buf; |
| do { |
| if (*str == 0x7f) |
| *p++ = '?'; |
| else if (*str == (char)0x9b) |
| /* VT100's CSI, aka Meta-ESC. Who's inventor? */ |
| /* I want to know who committed this sin */ |
| *p++ = '{'; |
| else |
| *p++ = ctrlconv[(unsigned char)*str]; |
| str++; |
| } while (--n); |
| *p = '\0'; |
| print_hilite(buf); |
| } |
| puts(str); |
| } |
| |
| /* Print the buffer */ |
| static void buffer_print(void) |
| { |
| unsigned i; |
| |
| move_cursor(0, 0); |
| for (i = 0; i <= max_displayed_line; i++) |
| if (pattern_valid) |
| print_found(buffer[i]); |
| else |
| print_ascii(buffer[i]); |
| status_print(); |
| } |
| |
| static void buffer_fill_and_print(void) |
| { |
| unsigned i; |
| #if ENABLE_FEATURE_LESS_DASHCMD |
| int fpos = cur_fline; |
| |
| if (option_mask32 & FLAG_S) { |
| /* Go back to the beginning of this line */ |
| while (fpos && LINENO(flines[fpos]) == LINENO(flines[fpos-1])) |
| fpos--; |
| } |
| |
| i = 0; |
| while (i <= max_displayed_line && fpos <= max_fline) { |
| int lineno = LINENO(flines[fpos]); |
| buffer[i] = flines[fpos]; |
| i++; |
| do { |
| fpos++; |
| } while ((fpos <= max_fline) |
| && (option_mask32 & FLAG_S) |
| && lineno == LINENO(flines[fpos]) |
| ); |
| } |
| #else |
| for (i = 0; i <= max_displayed_line && cur_fline + i <= max_fline; i++) { |
| buffer[i] = flines[cur_fline + i]; |
| } |
| #endif |
| for (; i <= max_displayed_line; i++) { |
| buffer[i] = empty_line_marker; |
| } |
| buffer_print(); |
| } |
| |
| /* Move the buffer up and down in the file in order to scroll */ |
| static void buffer_down(int nlines) |
| { |
| cur_fline += nlines; |
| read_lines(); |
| cap_cur_fline(nlines); |
| buffer_fill_and_print(); |
| } |
| |
| static void buffer_up(int nlines) |
| { |
| cur_fline -= nlines; |
| if (cur_fline < 0) cur_fline = 0; |
| read_lines(); |
| buffer_fill_and_print(); |
| } |
| |
| static void buffer_line(int linenum) |
| { |
| if (linenum < 0) |
| linenum = 0; |
| cur_fline = linenum; |
| read_lines(); |
| if (linenum + max_displayed_line > max_fline) |
| linenum = max_fline - max_displayed_line + TILDES; |
| if (linenum < 0) |
| linenum = 0; |
| cur_fline = linenum; |
| buffer_fill_and_print(); |
| } |
| |
| static void open_file_and_read_lines(void) |
| { |
| if (filename) { |
| xmove_fd(xopen(filename, O_RDONLY), STDIN_FILENO); |
| } else { |
| /* "less" with no arguments in argv[] */ |
| /* For status line only */ |
| filename = xstrdup(bb_msg_standard_input); |
| } |
| readpos = 0; |
| readeof = 0; |
| last_line_pos = 0; |
| terminated = 1; |
| read_lines(); |
| } |
| |
| /* Reinitialize everything for a new file - free the memory and start over */ |
| static void reinitialize(void) |
| { |
| unsigned i; |
| |
| if (flines) { |
| for (i = 0; i <= max_fline; i++) |
| free(MEMPTR(flines[i])); |
| free(flines); |
| flines = NULL; |
| } |
| |
| max_fline = -1; |
| cur_fline = 0; |
| max_lineno = 0; |
| open_file_and_read_lines(); |
| #if ENABLE_FEATURE_LESS_ASK_TERMINAL |
| if (G.winsize_err) |
| printf("\033[999;999H" "\033[6n"); |
| #endif |
| buffer_fill_and_print(); |
| } |
| |
| static int64_t getch_nowait(void) |
| { |
| int rd; |
| int64_t key64; |
| struct pollfd pfd[2]; |
| |
| pfd[0].fd = STDIN_FILENO; |
| pfd[0].events = POLLIN; |
| pfd[1].fd = kbd_fd; |
| pfd[1].events = POLLIN; |
| again: |
| tcsetattr(kbd_fd, TCSANOW, &term_less); |
| /* NB: select/poll returns whenever read will not block. Therefore: |
| * if eof is reached, select/poll will return immediately |
| * because read will immediately return 0 bytes. |
| * Even if select/poll says that input is available, read CAN block |
| * (switch fd into O_NONBLOCK'ed mode to avoid it) |
| */ |
| rd = 1; |
| /* Are we interested in stdin? */ |
| //TODO: reuse code for determining this |
| if (!(option_mask32 & FLAG_S) |
| ? !(max_fline > cur_fline + max_displayed_line) |
| : !(max_fline >= cur_fline |
| && max_lineno > LINENO(flines[cur_fline]) + max_displayed_line) |
| ) { |
| if (eof_error > 0) /* did NOT reach eof yet */ |
| rd = 0; /* yes, we are interested in stdin */ |
| } |
| /* Position cursor if line input is done */ |
| if (less_gets_pos >= 0) |
| move_cursor(max_displayed_line + 2, less_gets_pos + 1); |
| fflush_all(); |
| |
| if (kbd_input[0] == 0) { /* if nothing is buffered */ |
| #if ENABLE_FEATURE_LESS_WINCH |
| while (1) { |
| int r; |
| /* NB: SIGWINCH interrupts poll() */ |
| r = poll(pfd + rd, 2 - rd, -1); |
| if (/*r < 0 && errno == EINTR &&*/ winch_counter) |
| return '\\'; /* anything which has no defined function */ |
| if (r) break; |
| } |
| #else |
| safe_poll(pfd + rd, 2 - rd, -1); |
| #endif |
| } |
| |
| /* We have kbd_fd in O_NONBLOCK mode, read inside read_key() |
| * would not block even if there is no input available */ |
| key64 = read_key(kbd_fd, kbd_input, /*timeout off:*/ -2); |
| if ((int)key64 == -1) { |
| if (errno == EAGAIN) { |
| /* No keyboard input available. Since poll() did return, |
| * we should have input on stdin */ |
| read_lines(); |
| buffer_fill_and_print(); |
| goto again; |
| } |
| /* EOF/error (ssh session got killed etc) */ |
| less_exit(0); |
| } |
| set_tty_cooked(); |
| return key64; |
| } |
| |
| /* Grab a character from input without requiring the return key. |
| * May return KEYCODE_xxx values. |
| * Note that this function works best with raw input. */ |
| static int64_t less_getch(int pos) |
| { |
| int64_t key64; |
| int key; |
| |
| again: |
| less_gets_pos = pos; |
| key = key64 = getch_nowait(); |
| less_gets_pos = -1; |
| |
| /* Discard Ctrl-something chars. |
| * (checking only lower 32 bits is a size optimization: |
| * upper 32 bits are used only by KEYCODE_CURSOR_POS) |
| */ |
| if (key >= 0 && key < ' ' && key != 0x0d && key != 8) |
| goto again; |
| |
| return key64; |
| } |
| |
| static char* less_gets(int sz) |
| { |
| int c; |
| unsigned i = 0; |
| char *result = xzalloc(1); |
| |
| while (1) { |
| c = '\0'; |
| less_gets_pos = sz + i; |
| c = getch_nowait(); |
| if (c == 0x0d) { |
| result[i] = '\0'; |
| less_gets_pos = -1; |
| return result; |
| } |
| if (c == 0x7f) |
| c = 8; |
| if (c == 8 && i) { |
| printf("\x8 \x8"); |
| i--; |
| } |
| if (c < ' ') /* filters out KEYCODE_xxx too (<0) */ |
| continue; |
| if (i >= width - sz - 1) |
| continue; /* len limit */ |
| bb_putchar(c); |
| result[i++] = c; |
| result = xrealloc(result, i+1); |
| } |
| } |
| |
| static void examine_file(void) |
| { |
| char *new_fname; |
| |
| print_statusline("Examine: "); |
| new_fname = less_gets(sizeof("Examine: ") - 1); |
| if (!new_fname[0]) { |
| status_print(); |
| err: |
| free(new_fname); |
| return; |
| } |
| if (access(new_fname, R_OK) != 0) { |
| print_statusline("Cannot read this file"); |
| goto err; |
| } |
| free(filename); |
| filename = new_fname; |
| /* files start by = argv. why we assume that argv is infinitely long?? |
| files[num_files] = filename; |
| current_file = num_files + 1; |
| num_files++; */ |
| files[0] = filename; |
| num_files = current_file = 1; |
| reinitialize(); |
| } |
| |
| /* This function changes the file currently being paged. direction can be one of the following: |
| * -1: go back one file |
| * 0: go to the first file |
| * 1: go forward one file */ |
| static void change_file(int direction) |
| { |
| if (current_file != ((direction > 0) ? num_files : 1)) { |
| current_file = direction ? current_file + direction : 1; |
| free(filename); |
| filename = xstrdup(files[current_file - 1]); |
| reinitialize(); |
| } else { |
| print_statusline(direction > 0 ? "No next file" : "No previous file"); |
| } |
| } |
| |
| static void remove_current_file(void) |
| { |
| unsigned i; |
| |
| if (num_files < 2) |
| return; |
| |
| if (current_file != 1) { |
| change_file(-1); |
| for (i = 3; i <= num_files; i++) |
| files[i - 2] = files[i - 1]; |
| num_files--; |
| } else { |
| change_file(1); |
| for (i = 2; i <= num_files; i++) |
| files[i - 2] = files[i - 1]; |
| num_files--; |
| current_file--; |
| } |
| } |
| |
| static void colon_process(void) |
| { |
| int keypress; |
| |
| /* Clear the current line and print a prompt */ |
| print_statusline(" :"); |
| |
| keypress = less_getch(2); |
| switch (keypress) { |
| case 'd': |
| remove_current_file(); |
| break; |
| case 'e': |
| examine_file(); |
| break; |
| #if ENABLE_FEATURE_LESS_FLAGS |
| case 'f': |
| m_status_print(); |
| break; |
| #endif |
| case 'n': |
| change_file(1); |
| break; |
| case 'p': |
| change_file(-1); |
| break; |
| case 'q': |
| less_exit(EXIT_SUCCESS); |
| break; |
| case 'x': |
| change_file(0); |
| break; |
| } |
| } |
| |
| #if ENABLE_FEATURE_LESS_REGEXP |
| static void normalize_match_pos(int match) |
| { |
| if (match >= num_matches) |
| match = num_matches - 1; |
| if (match < 0) |
| match = 0; |
| match_pos = match; |
| } |
| |
| static void goto_match(int match) |
| { |
| if (!pattern_valid) |
| return; |
| if (match < 0) |
| match = 0; |
| /* Try to find next match if eof isn't reached yet */ |
| if (match >= num_matches && eof_error > 0) { |
| wanted_match = match; /* "I want to read until I see N'th match" */ |
| read_lines(); |
| } |
| if (num_matches) { |
| normalize_match_pos(match); |
| buffer_line(match_lines[match_pos]); |
| } else { |
| print_statusline("No matches found"); |
| } |
| } |
| |
| static void fill_match_lines(unsigned pos) |
| { |
| if (!pattern_valid) |
| return; |
| /* Run the regex on each line of the current file */ |
| while (pos <= max_fline) { |
| /* If this line matches */ |
| if (regexec(&pattern, flines[pos], 0, NULL, 0) == 0 |
| /* and we didn't match it last time */ |
| && !(num_matches && match_lines[num_matches-1] == pos) |
| ) { |
| match_lines = xrealloc_vector(match_lines, 4, num_matches); |
| match_lines[num_matches++] = pos; |
| } |
| pos++; |
| } |
| } |
| |
| static void regex_process(void) |
| { |
| char *uncomp_regex, *err; |
| |
| /* Reset variables */ |
| free(match_lines); |
| match_lines = NULL; |
| match_pos = 0; |
| num_matches = 0; |
| if (pattern_valid) { |
| regfree(&pattern); |
| pattern_valid = 0; |
| } |
| |
| /* Get the uncompiled regular expression from the user */ |
| clear_line(); |
| bb_putchar((option_mask32 & LESS_STATE_MATCH_BACKWARDS) ? '?' : '/'); |
| uncomp_regex = less_gets(1); |
| if (!uncomp_regex[0]) { |
| free(uncomp_regex); |
| buffer_print(); |
| return; |
| } |
| |
| /* Compile the regex and check for errors */ |
| err = regcomp_or_errmsg(&pattern, uncomp_regex, |
| (option_mask32 & FLAG_I) ? REG_ICASE : 0); |
| free(uncomp_regex); |
| if (err) { |
| print_statusline(err); |
| free(err); |
| return; |
| } |
| |
| pattern_valid = 1; |
| match_pos = 0; |
| fill_match_lines(0); |
| while (match_pos < num_matches) { |
| if ((int)match_lines[match_pos] > cur_fline) |
| break; |
| match_pos++; |
| } |
| if (option_mask32 & LESS_STATE_MATCH_BACKWARDS) |
| match_pos--; |
| |
| /* It's possible that no matches are found yet. |
| * goto_match() will read input looking for match, |
| * if needed */ |
| goto_match(match_pos); |
| } |
| #endif |
| |
| static void number_process(int first_digit) |
| { |
| unsigned i; |
| int num; |
| int keypress; |
| char num_input[sizeof(int)*4]; /* more than enough */ |
| |
| num_input[0] = first_digit; |
| |
| /* Clear the current line, print a prompt, and then print the digit */ |
| clear_line(); |
| printf(":%c", first_digit); |
| |
| /* Receive input until a letter is given */ |
| i = 1; |
| while (i < sizeof(num_input)-1) { |
| keypress = less_getch(i + 1); |
| if ((unsigned)keypress > 255 || !isdigit(num_input[i])) |
| break; |
| num_input[i] = keypress; |
| bb_putchar(keypress); |
| i++; |
| } |
| |
| num_input[i] = '\0'; |
| num = bb_strtou(num_input, NULL, 10); |
| /* on format error, num == -1 */ |
| if (num < 1 || num > MAXLINES) { |
| buffer_print(); |
| return; |
| } |
| |
| /* We now know the number and the letter entered, so we process them */ |
| switch (keypress) { |
| case KEYCODE_DOWN: case 'z': case 'd': case 'e': case ' ': case '\015': |
| buffer_down(num); |
| break; |
| case KEYCODE_UP: case 'b': case 'w': case 'y': case 'u': |
| buffer_up(num); |
| break; |
| case 'g': case '<': case 'G': case '>': |
| cur_fline = num + max_displayed_line; |
| read_lines(); |
| buffer_line(num - 1); |
| break; |
| case 'p': case '%': |
| num = num * (max_fline / 100); /* + max_fline / 2; */ |
| cur_fline = num + max_displayed_line; |
| read_lines(); |
| buffer_line(num); |
| break; |
| #if ENABLE_FEATURE_LESS_REGEXP |
| case 'n': |
| goto_match(match_pos + num); |
| break; |
| case '/': |
| option_mask32 &= ~LESS_STATE_MATCH_BACKWARDS; |
| regex_process(); |
| break; |
| case '?': |
| option_mask32 |= LESS_STATE_MATCH_BACKWARDS; |
| regex_process(); |
| break; |
| #endif |
| } |
| } |
| |
| #if ENABLE_FEATURE_LESS_DASHCMD |
| static void flag_change(void) |
| { |
| int keypress; |
| |
| clear_line(); |
| bb_putchar('-'); |
| keypress = less_getch(1); |
| |
| switch (keypress) { |
| case 'M': |
| option_mask32 ^= FLAG_M; |
| break; |
| case 'm': |
| option_mask32 ^= FLAG_m; |
| break; |
| case 'E': |
| option_mask32 ^= FLAG_E; |
| break; |
| case '~': |
| option_mask32 ^= FLAG_TILDE; |
| break; |
| case 'S': |
| option_mask32 ^= FLAG_S; |
| buffer_fill_and_print(); |
| break; |
| #if ENABLE_FEATURE_LESS_LINENUMS |
| case 'N': |
| option_mask32 ^= FLAG_N; |
| re_wrap(); |
| buffer_fill_and_print(); |
| break; |
| #endif |
| } |
| } |
| |
| #ifdef BLOAT |
| static void show_flag_status(void) |
| { |
| int keypress; |
| int flag_val; |
| |
| clear_line(); |
| bb_putchar('_'); |
| keypress = less_getch(1); |
| |
| switch (keypress) { |
| case 'M': |
| flag_val = option_mask32 & FLAG_M; |
| break; |
| case 'm': |
| flag_val = option_mask32 & FLAG_m; |
| break; |
| case '~': |
| flag_val = option_mask32 & FLAG_TILDE; |
| break; |
| case 'N': |
| flag_val = option_mask32 & FLAG_N; |
| break; |
| case 'E': |
| flag_val = option_mask32 & FLAG_E; |
| break; |
| default: |
| flag_val = 0; |
| break; |
| } |
| |
| clear_line(); |
| printf(HIGHLIGHT"The status of the flag is: %u"NORMAL, flag_val != 0); |
| } |
| #endif |
| |
| #endif /* ENABLE_FEATURE_LESS_DASHCMD */ |
| |
| static void save_input_to_file(void) |
| { |
| const char *msg = ""; |
| char *current_line; |
| unsigned i; |
| FILE *fp; |
| |
| print_statusline("Log file: "); |
| current_line = less_gets(sizeof("Log file: ")-1); |
| if (current_line[0]) { |
| fp = fopen_for_write(current_line); |
| if (!fp) { |
| msg = "Error opening log file"; |
| goto ret; |
| } |
| for (i = 0; i <= max_fline; i++) |
| fprintf(fp, "%s\n", flines[i]); |
| fclose(fp); |
| msg = "Done"; |
| } |
| ret: |
| print_statusline(msg); |
| free(current_line); |
| } |
| |
| #if ENABLE_FEATURE_LESS_MARKS |
| static void add_mark(void) |
| { |
| int letter; |
| |
| print_statusline("Mark: "); |
| letter = less_getch(sizeof("Mark: ") - 1); |
| |
| if (isalpha(letter)) { |
| /* If we exceed 15 marks, start overwriting previous ones */ |
| if (num_marks == 14) |
| num_marks = 0; |
| |
| mark_lines[num_marks][0] = letter; |
| mark_lines[num_marks][1] = cur_fline; |
| num_marks++; |
| } else { |
| print_statusline("Invalid mark letter"); |
| } |
| } |
| |
| static void goto_mark(void) |
| { |
| int letter; |
| int i; |
| |
| print_statusline("Go to mark: "); |
| letter = less_getch(sizeof("Go to mark: ") - 1); |
| clear_line(); |
| |
| if (isalpha(letter)) { |
| for (i = 0; i <= num_marks; i++) |
| if (letter == mark_lines[i][0]) { |
| buffer_line(mark_lines[i][1]); |
| break; |
| } |
| if (num_marks == 14 && letter != mark_lines[14][0]) |
| print_statusline("Mark not set"); |
| } else |
| print_statusline("Invalid mark letter"); |
| } |
| #endif |
| |
| #if ENABLE_FEATURE_LESS_BRACKETS |
| static char opp_bracket(char bracket) |
| { |
| switch (bracket) { |
| case '{': case '[': /* '}' == '{' + 2. Same for '[' */ |
| bracket++; |
| case '(': /* ')' == '(' + 1 */ |
| bracket++; |
| break; |
| case '}': case ']': |
| bracket--; |
| case ')': |
| bracket--; |
| break; |
| }; |
| return bracket; |
| } |
| |
| static void match_right_bracket(char bracket) |
| { |
| unsigned i; |
| |
| if (strchr(flines[cur_fline], bracket) == NULL) { |
| print_statusline("No bracket in top line"); |
| return; |
| } |
| bracket = opp_bracket(bracket); |
| for (i = cur_fline + 1; i < max_fline; i++) { |
| if (strchr(flines[i], bracket) != NULL) { |
| buffer_line(i); |
| return; |
| } |
| } |
| print_statusline("No matching bracket found"); |
| } |
| |
| static void match_left_bracket(char bracket) |
| { |
| int i; |
| |
| if (strchr(flines[cur_fline + max_displayed_line], bracket) == NULL) { |
| print_statusline("No bracket in bottom line"); |
| return; |
| } |
| |
| bracket = opp_bracket(bracket); |
| for (i = cur_fline + max_displayed_line; i >= 0; i--) { |
| if (strchr(flines[i], bracket) != NULL) { |
| buffer_line(i); |
| return; |
| } |
| } |
| print_statusline("No matching bracket found"); |
| } |
| #endif /* FEATURE_LESS_BRACKETS */ |
| |
| static void keypress_process(int keypress) |
| { |
| switch (keypress) { |
| case KEYCODE_DOWN: case 'e': case 'j': case 0x0d: |
| buffer_down(1); |
| break; |
| case KEYCODE_UP: case 'y': case 'k': |
| buffer_up(1); |
| break; |
| case KEYCODE_PAGEDOWN: case ' ': case 'z': case 'f': |
| buffer_down(max_displayed_line + 1); |
| break; |
| case KEYCODE_PAGEUP: case 'w': case 'b': |
| buffer_up(max_displayed_line + 1); |
| break; |
| case 'd': |
| buffer_down((max_displayed_line + 1) / 2); |
| break; |
| case 'u': |
| buffer_up((max_displayed_line + 1) / 2); |
| break; |
| case KEYCODE_HOME: case 'g': case 'p': case '<': case '%': |
| buffer_line(0); |
| break; |
| case KEYCODE_END: case 'G': case '>': |
| cur_fline = MAXLINES; |
| read_lines(); |
| buffer_line(cur_fline); |
| break; |
| case 'q': case 'Q': |
| less_exit(EXIT_SUCCESS); |
| break; |
| #if ENABLE_FEATURE_LESS_MARKS |
| case 'm': |
| add_mark(); |
| buffer_print(); |
| break; |
| case '\'': |
| goto_mark(); |
| buffer_print(); |
| break; |
| #endif |
| case 'r': case 'R': |
| /* TODO: (1) also bind ^R, ^L to this? |
| * (2) re-measure window size? |
| */ |
| buffer_print(); |
| break; |
| /*case 'R': |
| full_repaint(); |
| break;*/ |
| case 's': |
| save_input_to_file(); |
| break; |
| case 'E': |
| examine_file(); |
| break; |
| #if ENABLE_FEATURE_LESS_FLAGS |
| case '=': |
| m_status_print(); |
| break; |
| #endif |
| #if ENABLE_FEATURE_LESS_REGEXP |
| case '/': |
| option_mask32 &= ~LESS_STATE_MATCH_BACKWARDS; |
| regex_process(); |
| break; |
| case 'n': |
| goto_match(match_pos + 1); |
| break; |
| case 'N': |
| goto_match(match_pos - 1); |
| break; |
| case '?': |
| option_mask32 |= LESS_STATE_MATCH_BACKWARDS; |
| regex_process(); |
| break; |
| #endif |
| #if ENABLE_FEATURE_LESS_DASHCMD |
| case '-': |
| flag_change(); |
| buffer_print(); |
| break; |
| #ifdef BLOAT |
| case '_': |
| show_flag_status(); |
| break; |
| #endif |
| #endif |
| #if ENABLE_FEATURE_LESS_BRACKETS |
| case '{': case '(': case '[': |
| match_right_bracket(keypress); |
| break; |
| case '}': case ')': case ']': |
| match_left_bracket(keypress); |
| break; |
| #endif |
| case ':': |
| colon_process(); |
| break; |
| } |
| |
| if (isdigit(keypress)) |
| number_process(keypress); |
| } |
| |
| static void sig_catcher(int sig) |
| { |
| less_exit(- sig); |
| } |
| |
| #if ENABLE_FEATURE_LESS_WINCH |
| static void sigwinch_handler(int sig UNUSED_PARAM) |
| { |
| winch_counter++; |
| } |
| #endif |
| |
| int less_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| int less_main(int argc, char **argv) |
| { |
| INIT_G(); |
| |
| /* TODO: -x: do not interpret backspace, -xx: tab also */ |
| /* -xxx: newline also */ |
| /* -w N: assume width N (-xxx -w 32: hex viewer of sorts) */ |
| getopt32(argv, "EMmN~I" IF_FEATURE_LESS_DASHCMD("S")); |
| argc -= optind; |
| argv += optind; |
| num_files = argc; |
| files = argv; |
| |
| /* Another popular pager, most, detects when stdout |
| * is not a tty and turns into cat. This makes sense. */ |
| if (!isatty(STDOUT_FILENO)) |
| return bb_cat(argv); |
| |
| if (!num_files) { |
| if (isatty(STDIN_FILENO)) { |
| /* Just "less"? No args and no redirection? */ |
| bb_error_msg("missing filename"); |
| bb_show_usage(); |
| } |
| } else { |
| filename = xstrdup(files[0]); |
| } |
| |
| if (option_mask32 & FLAG_TILDE) |
| empty_line_marker = ""; |
| |
| kbd_fd = open(CURRENT_TTY, O_RDONLY); |
| if (kbd_fd < 0) |
| return bb_cat(argv); |
| ndelay_on(kbd_fd); |
| |
| tcgetattr(kbd_fd, &term_orig); |
| term_less = term_orig; |
| term_less.c_lflag &= ~(ICANON | ECHO); |
| term_less.c_iflag &= ~(IXON | ICRNL); |
| /*term_less.c_oflag &= ~ONLCR;*/ |
| term_less.c_cc[VMIN] = 1; |
| term_less.c_cc[VTIME] = 0; |
| |
| IF_FEATURE_LESS_ASK_TERMINAL(G.winsize_err =) get_terminal_width_height(kbd_fd, &width, &max_displayed_line); |
| /* 20: two tabstops + 4 */ |
| if (width < 20 || max_displayed_line < 3) |
| return bb_cat(argv); |
| max_displayed_line -= 2; |
| |
| /* We want to restore term_orig on exit */ |
| bb_signals(BB_FATAL_SIGS, sig_catcher); |
| #if ENABLE_FEATURE_LESS_WINCH |
| signal(SIGWINCH, sigwinch_handler); |
| #endif |
| |
| buffer = xmalloc((max_displayed_line+1) * sizeof(char *)); |
| reinitialize(); |
| while (1) { |
| int64_t keypress; |
| |
| #if ENABLE_FEATURE_LESS_WINCH |
| while (WINCH_COUNTER) { |
| again: |
| winch_counter--; |
| IF_FEATURE_LESS_ASK_TERMINAL(G.winsize_err =) get_terminal_width_height(kbd_fd, &width, &max_displayed_line); |
| IF_FEATURE_LESS_ASK_TERMINAL(got_size:) |
| /* 20: two tabstops + 4 */ |
| if (width < 20) |
| width = 20; |
| if (max_displayed_line < 3) |
| max_displayed_line = 3; |
| max_displayed_line -= 2; |
| free(buffer); |
| buffer = xmalloc((max_displayed_line+1) * sizeof(char *)); |
| /* Avoid re-wrap and/or redraw if we already know |
| * we need to do it again. These ops are expensive */ |
| if (WINCH_COUNTER) |
| goto again; |
| re_wrap(); |
| if (WINCH_COUNTER) |
| goto again; |
| buffer_fill_and_print(); |
| /* This took some time. Loop back and check, |
| * were there another SIGWINCH? */ |
| } |
| keypress = less_getch(-1); /* -1: do not position cursor */ |
| # if ENABLE_FEATURE_LESS_ASK_TERMINAL |
| if ((int32_t)keypress == KEYCODE_CURSOR_POS) { |
| uint32_t rc = (keypress >> 32); |
| width = (rc & 0x7fff); |
| max_displayed_line = ((rc >> 16) & 0x7fff); |
| goto got_size; |
| } |
| # endif |
| #else |
| keypress = less_getch(-1); /* -1: do not position cursor */ |
| #endif |
| keypress_process(keypress); |
| } |
| } |
| |
| /* |
| Help text of less version 418 is below. |
| If you are implementing something, keeping |
| key and/or command line switch compatibility is a good idea: |
| |
| |
| SUMMARY OF LESS COMMANDS |
| |
| Commands marked with * may be preceded by a number, N. |
| Notes in parentheses indicate the behavior if N is given. |
| h H Display this help. |
| q :q Q :Q ZZ Exit. |
| --------------------------------------------------------------------------- |
| MOVING |
| e ^E j ^N CR * Forward one line (or N lines). |
| y ^Y k ^K ^P * Backward one line (or N lines). |
| f ^F ^V SPACE * Forward one window (or N lines). |
| b ^B ESC-v * Backward one window (or N lines). |
| z * Forward one window (and set window to N). |
| w * Backward one window (and set window to N). |
| ESC-SPACE * Forward one window, but don't stop at end-of-file. |
| d ^D * Forward one half-window (and set half-window to N). |
| u ^U * Backward one half-window (and set half-window to N). |
| ESC-) RightArrow * Left one half screen width (or N positions). |
| ESC-( LeftArrow * Right one half screen width (or N positions). |
| F Forward forever; like "tail -f". |
| r ^R ^L Repaint screen. |
| R Repaint screen, discarding buffered input. |
| --------------------------------------------------- |
| Default "window" is the screen height. |
| Default "half-window" is half of the screen height. |
| --------------------------------------------------------------------------- |
| SEARCHING |
| /pattern * Search forward for (N-th) matching line. |
| ?pattern * Search backward for (N-th) matching line. |
| n * Repeat previous search (for N-th occurrence). |
| N * Repeat previous search in reverse direction. |
| ESC-n * Repeat previous search, spanning files. |
| ESC-N * Repeat previous search, reverse dir. & spanning files. |
| ESC-u Undo (toggle) search highlighting. |
| --------------------------------------------------- |
| Search patterns may be modified by one or more of: |
| ^N or ! Search for NON-matching lines. |
| ^E or * Search multiple files (pass thru END OF FILE). |
| ^F or @ Start search at FIRST file (for /) or last file (for ?). |
| ^K Highlight matches, but don't move (KEEP position). |
| ^R Don't use REGULAR EXPRESSIONS. |
| --------------------------------------------------------------------------- |
| JUMPING |
| g < ESC-< * Go to first line in file (or line N). |
| G > ESC-> * Go to last line in file (or line N). |
| p % * Go to beginning of file (or N percent into file). |
| t * Go to the (N-th) next tag. |
| T * Go to the (N-th) previous tag. |
| { ( [ * Find close bracket } ) ]. |
| } ) ] * Find open bracket { ( [. |
| ESC-^F <c1> <c2> * Find close bracket <c2>. |
| ESC-^B <c1> <c2> * Find open bracket <c1> |
| --------------------------------------------------- |
| Each "find close bracket" command goes forward to the close bracket |
| matching the (N-th) open bracket in the top line. |
| Each "find open bracket" command goes backward to the open bracket |
| matching the (N-th) close bracket in the bottom line. |
| m<letter> Mark the current position with <letter>. |
| '<letter> Go to a previously marked position. |
| '' Go to the previous position. |
| ^X^X Same as '. |
| --------------------------------------------------- |
| A mark is any upper-case or lower-case letter. |
| Certain marks are predefined: |
| ^ means beginning of the file |
| $ means end of the file |
| --------------------------------------------------------------------------- |
| CHANGING FILES |
| :e [file] Examine a new file. |
| ^X^V Same as :e. |
| :n * Examine the (N-th) next file from the command line. |
| :p * Examine the (N-th) previous file from the command line. |
| :x * Examine the first (or N-th) file from the command line. |
| :d Delete the current file from the command line list. |
| = ^G :f Print current file name. |
| --------------------------------------------------------------------------- |
| MISCELLANEOUS COMMANDS |
| -<flag> Toggle a command line option [see OPTIONS below]. |
| --<name> Toggle a command line option, by name. |
| _<flag> Display the setting of a command line option. |
| __<name> Display the setting of an option, by name. |
| +cmd Execute the less cmd each time a new file is examined. |
| !command Execute the shell command with $SHELL. |
| |Xcommand Pipe file between current pos & mark X to shell command. |
| v Edit the current file with $VISUAL or $EDITOR. |
| V Print version number of "less". |
| --------------------------------------------------------------------------- |
| OPTIONS |
| Most options may be changed either on the command line, |
| or from within less by using the - or -- command. |
| Options may be given in one of two forms: either a single |
| character preceded by a -, or a name preceeded by --. |
| -? ........ --help |
| Display help (from command line). |
| -a ........ --search-skip-screen |
| Forward search skips current screen. |
| -b [N] .... --buffers=[N] |
| Number of buffers. |
| -B ........ --auto-buffers |
| Don't automatically allocate buffers for pipes. |
| -c ........ --clear-screen |
| Repaint by clearing rather than scrolling. |
| -d ........ --dumb |
| Dumb terminal. |
| -D [xn.n] . --color=xn.n |
| Set screen colors. (MS-DOS only) |
| -e -E .... --quit-at-eof --QUIT-AT-EOF |
| Quit at end of file. |
| -f ........ --force |
| Force open non-regular files. |
| -F ........ --quit-if-one-screen |
| Quit if entire file fits on first screen. |
| -g ........ --hilite-search |
| Highlight only last match for searches. |
| -G ........ --HILITE-SEARCH |
| Don't highlight any matches for searches. |
| -h [N] .... --max-back-scroll=[N] |
| Backward scroll limit. |
| -i ........ --ignore-case |
| Ignore case in searches that do not contain uppercase. |
| -I ........ --IGNORE-CASE |
| Ignore case in all searches. |
| -j [N] .... --jump-target=[N] |
| Screen position of target lines. |
| -J ........ --status-column |
| Display a status column at left edge of screen. |
| -k [file] . --lesskey-file=[file] |
| Use a lesskey file. |
| -L ........ --no-lessopen |
| Ignore the LESSOPEN environment variable. |
| -m -M .... --long-prompt --LONG-PROMPT |
| Set prompt style. |
| -n -N .... --line-numbers --LINE-NUMBERS |
| Don't use line numbers. |
| -o [file] . --log-file=[file] |
| Copy to log file (standard input only). |
| -O [file] . --LOG-FILE=[file] |
| Copy to log file (unconditionally overwrite). |
| -p [pattern] --pattern=[pattern] |
| Start at pattern (from command line). |
| -P [prompt] --prompt=[prompt] |
| Define new prompt. |
| -q -Q .... --quiet --QUIET --silent --SILENT |
| Quiet the terminal bell. |
| -r -R .... --raw-control-chars --RAW-CONTROL-CHARS |
| Output "raw" control characters. |
| -s ........ --squeeze-blank-lines |
| Squeeze multiple blank lines. |
| -S ........ --chop-long-lines |
| Chop long lines. |
| -t [tag] .. --tag=[tag] |
| Find a tag. |
| -T [tagsfile] --tag-file=[tagsfile] |
| Use an alternate tags file. |
| -u -U .... --underline-special --UNDERLINE-SPECIAL |
| Change handling of backspaces. |
| -V ........ --version |
| Display the version number of "less". |
| -w ........ --hilite-unread |
| Highlight first new line after forward-screen. |
| -W ........ --HILITE-UNREAD |
| Highlight first new line after any forward movement. |
| -x [N[,...]] --tabs=[N[,...]] |
| Set tab stops. |
| -X ........ --no-init |
| Don't use termcap init/deinit strings. |
| --no-keypad |
| Don't use termcap keypad init/deinit strings. |
| -y [N] .... --max-forw-scroll=[N] |
| Forward scroll limit. |
| -z [N] .... --window=[N] |
| Set size of window. |
| -" [c[c]] . --quotes=[c[c]] |
| Set shell quote characters. |
| -~ ........ --tilde |
| Don't display tildes after end of file. |
| -# [N] .... --shift=[N] |
| Horizontal scroll amount (0 = one half screen width) |
| |
| --------------------------------------------------------------------------- |
| LINE EDITING |
| These keys can be used to edit text being entered |
| on the "command line" at the bottom of the screen. |
| RightArrow ESC-l Move cursor right one character. |
| LeftArrow ESC-h Move cursor left one character. |
| CNTL-RightArrow ESC-RightArrow ESC-w Move cursor right one word. |
| CNTL-LeftArrow ESC-LeftArrow ESC-b Move cursor left one word. |
| HOME ESC-0 Move cursor to start of line. |
| END ESC-$ Move cursor to end of line. |
| BACKSPACE Delete char to left of cursor. |
| DELETE ESC-x Delete char under cursor. |
| CNTL-BACKSPACE ESC-BACKSPACE Delete word to left of cursor. |
| CNTL-DELETE ESC-DELETE ESC-X Delete word under cursor. |
| CNTL-U ESC (MS-DOS only) Delete entire line. |
| UpArrow ESC-k Retrieve previous command line. |
| DownArrow ESC-j Retrieve next command line. |
| TAB Complete filename & cycle. |
| SHIFT-TAB ESC-TAB Complete filename & reverse cycle. |
| CNTL-L Complete filename, list all. |
| */ |