*
* Copyright (C) 2005 by Rob Sullivan <cogito.ergo.cogito@gmail.com>
*
- * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
/*
* redirected input has been read from stdin
*/
-#include "busybox.h"
+//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 -m/-M"
+//config: default y
+//config: depends on LESS
+//config: help
+//config: The -M/-m flag enables a more sophisticated status line.
+//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: "[-E" IF_FEATURE_LESS_FLAGS("Mm") "Nh~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: IF_FEATURE_LESS_FLAGS(
+//usage: "\n -M,-m Display status line with line numbers"
+//usage: "\n and percentage through the file"
+//usage: )
+//usage: "\n -N Prefix line number to each line"
+//usage: "\n -I Ignore case in all searches"
+//usage: "\n -~ Suppress ~s displayed past EOF"
+
+#include <sched.h> /* sched_yield() */
+
+#include "libbb.h"
#if ENABLE_FEATURE_LESS_REGEXP
#include "xregex.h"
#endif
-/* FIXME: currently doesn't work right */
-#undef ENABLE_FEATURE_LESS_FLAGCS
-#define ENABLE_FEATURE_LESS_FLAGCS 0
+#define ESC "\033"
/* The escape codes for highlighted and normal text */
-#define HIGHLIGHT "\033[7m"
-#define NORMAL "\033[0m"
-/* The escape code to clear the screen */
-#define CLEAR "\033[H\033[J"
-/* The escape code to clear to end of line */
-#define CLEAR_2_EOL "\033[K"
-
-/* These are the escape sequences corresponding to special keys */
-enum {
- REAL_KEY_UP = 'A',
- REAL_KEY_DOWN = 'B',
- REAL_KEY_RIGHT = 'C',
- REAL_KEY_LEFT = 'D',
- REAL_PAGE_UP = '5',
- REAL_PAGE_DOWN = '6',
- REAL_KEY_HOME = '7',
- REAL_KEY_END = '8',
- REAL_KEY_HOME_XTERM = 'H',
- REAL_KEY_END_XTERM = 'F',
-
-/* These are the special codes assigned by this program to the special keys */
- KEY_UP = 20,
- KEY_DOWN = 21,
- KEY_RIGHT = 22,
- KEY_LEFT = 23,
- PAGE_UP = 24,
- PAGE_DOWN = 25,
- KEY_HOME = 26,
- KEY_END = 27,
+#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,
};
-static unsigned max_displayed_line;
-static unsigned width;
-static const char *empty_line_marker = "~";
-
-static char *filename;
-static char **files;
-static unsigned num_files = 1;
-static unsigned current_file = 1;
-static const char **buffer;
-static const char **flines;
-static int cur_fline; /* signed */
-static unsigned max_fline;
-static unsigned max_lineno; /* this one tracks linewrap */
-
-static ssize_t eof_error = 1; /* eof if 0, error if < 0 */
-static char terminated = 1;
-static size_t readpos;
-static size_t readeof;
-/* last position in last line, taking into account tabs */
-static size_t linepos;
-
/* Command line options */
enum {
- FLAG_E = 1,
+ 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_MARKS
-static unsigned mark_lines[15][2];
-static unsigned num_marks;
+#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
-static unsigned *match_lines;
-static int match_pos; /* signed! */
-static unsigned num_matches;
-static regex_t pattern;
-static unsigned pattern_valid;
-#else
-enum { pattern_valid = 0 };
+ 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))
-static struct termios term_orig, term_vi;
-
-/* File pointer to get input from */
-static int kbd_fd;
/* Reset terminal input to normal */
static void set_tty_cooked(void)
{
- fflush(stdout);
+ fflush_all();
tcsetattr(kbd_fd, TCSANOW, &term_orig);
}
-/* Exit the program gracefully */
-static void less_exit(int code)
-{
- /* TODO: We really should save the terminal state when we start,
- * and restore it when we exit. Less does this with the
- * "ti" and "te" termcap commands; can this be done with
- * only termios.h? */
- putchar('\n');
- fflush_stdout_and_exit(code);
-}
-
/* 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("\033[%u;%uH", line, row);
+ printf(ESC"[%u;%uH", line, row);
}
static void clear_line(void)
{
- printf("\033[%u;0H" CLEAR_2_EOL, max_displayed_line + 2);
+ printf(ESC"[%u;0H" CLEAR_2_EOL, max_displayed_line + 2);
}
static void print_hilite(const char *str)
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;
- USE_FEATURE_LESS_REGEXP(unsigned old_max_fline = max_fline;)
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;
- current_line = xmalloc(w);
- p = current_line;
+ 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];
- if (option_mask32 & FLAG_N)
- cp += 8;
- strcpy(current_line, cp);
+ strcpy(p, cp);
p += strlen(current_line);
+ free(MEMPTR(flines[max_fline]));
+ /* last_line_pos is still valid from previous read_lines() */
} else {
- linepos = 0;
+ last_line_pos = 0;
}
- while (1) {
- again:
+ while (1) { /* read lines until we reach cur_fline or wanted_match */
*p = '\0';
terminated = 0;
- while (1) {
+ 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(0, readbuf, sizeof(readbuf));
+ eof_error = safe_read(STDIN_FILENO, readbuf, sizeof(readbuf));
ndelay_off(0);
readpos = 0;
readeof = eof_error;
- if (eof_error < 0) {
- readeof = 0;
- if (errno != EAGAIN)
- print_statusline("read error");
- }
- if (eof_error <= 0) {
+ 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' && linepos && p[-1] != '\t') {
+ if (c == '\x8' && last_line_pos && p[-1] != '\t') {
readpos++; /* eat it */
- linepos--;
+ last_line_pos--;
+ /* was buggy (p could end up <= current_line)... */
*--p = '\0';
continue;
}
- if (c == '\t')
- linepos += (linepos^7) & 7;
- linepos++;
- if (linepos >= w)
- break;
+ {
+ 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; break; }
+ 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++;
- goto again;
+ continue;
}
reached_eof:
last_terminated = terminated;
- flines = xrealloc(flines, (max_fline+1) * sizeof(char *));
- if (option_mask32 & FLAG_N) {
- /* Width of 7 preserves tab spacing in the text */
- flines[max_fline] = xasprintf(
- (max_lineno <= 9999999) ? "%7u %s" : "%07u %s",
- max_lineno % 10000000, current_line);
- free(current_line);
- if (terminated)
- max_lineno++;
- } else {
- flines[max_fline] = xrealloc(current_line, strlen(current_line)+1);
- }
- if (max_fline >= MAXLINES)
+ 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 (max_fline > cur_fline + max_displayed_line)
+ }
+ 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 && errno == EAGAIN) {
- /* not yet eof or error, reset flag (or else
- * we will hog CPU - select() will return
- * immediately */
- eof_error = 1;
+ 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 = xmalloc(w);
+ current_line = ((char*)xmalloc(w + 4)) + 4;
p = current_line;
- linepos = 0;
- }
+ 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
}
{
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(" lines %i-%i/%i ",
cur_fline + 1, cur_fline + max_displayed_line + 1,
max_fline + 1);
- if (cur_fline >= max_fline - max_displayed_line) {
+ 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]);
{
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)) {
#endif
clear_line();
- if (cur_fline && cur_fline < max_fline - max_displayed_line) {
- putchar(':');
+ if (cur_fline && cur_fline < (int)(max_fline - max_displayed_line)) {
+ bb_putchar(':');
return;
}
p = "(END)";
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 */
+ * to the end of the file */
if (diff > 0)
cur_fline += diff;
}
}
-static char controls[] =
+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 char ctrlconv[] =
- /* '\n': it's a former NUL - subst with '@', not 'J' */
+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)
{
regmatch_t match_structs;
char buf[width];
+ char nbuf9[9];
const char *str = line;
char *p = buf;
size_t n;
/* 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[]) */
+ * 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;
while (match_status == 0) {
char *new = xasprintf("%s%.*s"HIGHLIGHT"%.*s"NORMAL,
- growline ? : "",
- match_structs.rm_so, str,
- match_structs.rm_eo - match_structs.rm_so,
+ 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;
+ 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\n", str);
+ printf(CLEAR_2_EOL"%s%s\n", nbuf9, str);
return;
}
- printf(CLEAR_2_EOL"%s%s\n", growline, str);
+ printf(CLEAR_2_EOL"%s%s%s\n", nbuf9, growline, str);
free(growline);
}
#else
static void print_ascii(const char *str)
{
char buf[width];
+ char nbuf9[9];
char *p;
size_t n;
- printf(CLEAR_2_EOL);
+ lineno_str(nbuf9, str);
+ printf(CLEAR_2_EOL"%s", nbuf9);
+
while (*str) {
n = strcspn(str, controls);
if (n) {
/* Print the buffer */
static void buffer_print(void)
{
- int i;
+ unsigned i;
move_cursor(0, 0);
for (i = 0; i <= max_displayed_line; i++)
static void buffer_fill_and_print(void)
{
- int i;
+ 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;
}
static void open_file_and_read_lines(void)
{
if (filename) {
- int fd = xopen(filename, O_RDONLY);
- dup2(fd, 0);
- if (fd) close(fd);
+ xmove_fd(xopen(filename, O_RDONLY), STDIN_FILENO);
} else {
/* "less" with no arguments in argv[] */
/* For status line only */
}
readpos = 0;
readeof = 0;
- linepos = 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)
{
- int i;
+ unsigned i;
if (flines) {
for (i = 0; i <= max_fline; i++)
- free((void*)(flines[i]));
+ free(MEMPTR(flines[i]));
free(flines);
flines = NULL;
}
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 void getch_nowait(char* input, int sz)
+static int64_t getch_nowait(void)
{
- ssize_t rd;
- fd_set readfds;
+ 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:
- fflush(stdout);
-
- /* NB: select returns whenever read will not block. Therefore:
- * (a) with O_NONBLOCK'ed fds select will return immediately
- * (b) if eof is reached, select will also return
- * because read will immediately return 0 bytes.
- * Even if select says that input is available, read CAN block
+ 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)
*/
- FD_ZERO(&readfds);
- if (max_fline <= cur_fline + max_displayed_line
- && eof_error > 0 /* did NOT reach eof yet */
+ 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)
) {
- /* We are interested in stdin */
- FD_SET(0, &readfds);
+ if (eof_error > 0) /* did NOT reach eof yet */
+ rd = 0; /* yes, we are interested in stdin */
}
- FD_SET(kbd_fd, &readfds);
- tcsetattr(kbd_fd, TCSANOW, &term_vi);
- select(kbd_fd + 1, &readfds, NULL, NULL, NULL);
-
- input[0] = '\0';
- ndelay_on(kbd_fd);
- rd = read(kbd_fd, input, sz);
- ndelay_off(kbd_fd);
- if (rd < 0) {
- /* No keyboard input, but we have input on stdin! */
- if (errno != EAGAIN) /* Huh?? */
- return;
- read_lines();
- buffer_fill_and_print();
- goto again;
+ /* 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. If the
- * character is ASCII \033, get more characters and assign certain sequences
- * special return codes. Note that this function works best with raw input. */
-static int less_getch(void)
+/* 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)
{
- char input[16];
- unsigned i;
+ int64_t key64;
+ int key;
+
again:
- getch_nowait(input, sizeof(input));
- /* Detect escape sequences (i.e. arrow keys) and handle
- * them accordingly */
-
- if (input[0] == '\033' && input[1] == '[') {
- set_tty_cooked();
- i = input[2] - REAL_KEY_UP;
- if (i < 4)
- return 20 + i;
- i = input[2] - REAL_PAGE_UP;
- if (i < 4)
- return 24 + i;
- if (input[2] == REAL_KEY_HOME_XTERM)
- return KEY_HOME;
- if (input[2] == REAL_KEY_END_XTERM)
- return KEY_END;
- return 0;
- }
- /* Reject almost all control chars */
- i = input[0];
- if (i < ' ' && i != 0x0d && i != 8) goto again;
- set_tty_cooked();
- return i;
+ 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)
{
- char c;
- int i = 0;
+ int c;
+ unsigned i = 0;
char *result = xzalloc(1);
- while (1) {
- fflush(stdout);
-
- /* I be damned if I know why is it needed *repeatedly*,
- * but it is needed. Is it because of stdio? */
- tcsetattr(kbd_fd, TCSANOW, &term_vi);
- read(kbd_fd, &c, 1);
- if (c == 0x0d)
+ 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 < ' ')
+ if (c < ' ') /* filters out KEYCODE_xxx too (<0) */
continue;
if (i >= width - sz - 1)
continue; /* len limit */
- putchar(c);
+ bb_putchar(c);
result[i++] = c;
result = xrealloc(result, i+1);
- result[i] = '\0';
}
}
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 = less_gets(sizeof("Examine: ")-1);
+ filename = new_fname;
/* files start by = argv. why we assume that argv is infinitely long??
files[num_files] = filename;
current_file = num_files + 1;
static void remove_current_file(void)
{
- int i;
+ unsigned i;
if (num_files < 2)
return;
/* Clear the current line and print a prompt */
print_statusline(" :");
- keypress = less_getch();
+ keypress = less_getch(2);
switch (keypress) {
case 'd':
remove_current_file();
change_file(-1);
break;
case 'q':
- less_exit(0);
+ less_exit(EXIT_SUCCESS);
break;
case 'x':
change_file(0);
match = 0;
/* Try to find next match if eof isn't reached yet */
if (match >= num_matches && eof_error > 0) {
- cur_fline = MAXLINES; /* look as far as needed */
+ wanted_match = match; /* "I want to read until I see N'th match" */
read_lines();
- cap_cur_fline(cur_fline);
}
if (num_matches) {
normalize_match_pos(match);
buffer_line(match_lines[match_pos]);
+ } else {
+ print_statusline("No matches found");
}
}
/* and we didn't match it last time */
&& !(num_matches && match_lines[num_matches-1] == pos)
) {
- match_lines = xrealloc(match_lines, (num_matches+1) * sizeof(int));
+ match_lines = xrealloc_vector(match_lines, 4, num_matches);
match_lines[num_matches++] = pos;
}
pos++;
/* Get the uncompiled regular expression from the user */
clear_line();
- putchar((option_mask32 & LESS_STATE_MATCH_BACKWARDS) ? '?' : '/');
+ bb_putchar((option_mask32 & LESS_STATE_MATCH_BACKWARDS) ? '?' : '/');
uncomp_regex = less_gets(1);
if (!uncomp_regex[0]) {
free(uncomp_regex);
}
/* Compile the regex and check for errors */
- err = regcomp_or_errmsg(&pattern, uncomp_regex, 0);
+ 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);
-
- if (num_matches == 0 || max_fline <= max_displayed_line) {
- buffer_print();
- return;
- }
while (match_pos < num_matches) {
- if (match_lines[match_pos] > cur_fline)
+ if ((int)match_lines[match_pos] > cur_fline)
break;
match_pos++;
}
if (option_mask32 & LESS_STATE_MATCH_BACKWARDS)
match_pos--;
- normalize_match_pos(match_pos);
- buffer_line(match_lines[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)
{
- int i = 1;
+ unsigned i;
int num;
+ int keypress;
char num_input[sizeof(int)*4]; /* more than enough */
- char keypress;
num_input[0] = first_digit;
printf(":%c", first_digit);
/* Receive input until a letter is given */
+ i = 1;
while (i < sizeof(num_input)-1) {
- num_input[i] = less_getch();
- if (!num_input[i] || !isdigit(num_input[i]))
+ keypress = less_getch(i + 1);
+ if ((unsigned)keypress > 255 || !isdigit(num_input[i]))
break;
- putchar(num_input[i]);
+ num_input[i] = keypress;
+ bb_putchar(keypress);
i++;
}
- /* Take the final letter out of the digits string */
- keypress = num_input[i];
num_input[i] = '\0';
num = bb_strtou(num_input, NULL, 10);
/* on format error, num == -1 */
/* We now know the number and the letter entered, so we process them */
switch (keypress) {
- case KEY_DOWN: case 'z': case 'd': case 'e': case ' ': case '\015':
+ case KEYCODE_DOWN: case 'z': case 'd': case 'e': case ' ': case '\015':
buffer_down(num);
break;
- case KEY_UP: case 'b': case 'w': case 'y': case 'u':
+ case KEYCODE_UP: case 'b': case 'w': case 'y': case 'u':
buffer_up(num);
break;
case 'g': case '<': case 'G': case '>':
}
}
-#if ENABLE_FEATURE_LESS_FLAGCS
+#if ENABLE_FEATURE_LESS_DASHCMD
static void flag_change(void)
{
int keypress;
clear_line();
- putchar('-');
- keypress = less_getch();
+ bb_putchar('-');
+ keypress = less_getch(1);
switch (keypress) {
case 'M':
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();
- putchar('_');
- keypress = less_getch();
+ bb_putchar('_');
+ keypress = less_getch(1);
switch (keypress) {
case 'M':
}
#endif
+#endif /* ENABLE_FEATURE_LESS_DASHCMD */
+
static void save_input_to_file(void)
{
const char *msg = "";
char *current_line;
- int i;
+ unsigned i;
FILE *fp;
print_statusline("Log file: ");
current_line = less_gets(sizeof("Log file: ")-1);
- if (strlen(current_line) > 0) {
- fp = fopen(current_line, "w");
+ if (current_line[0]) {
+ fp = fopen_for_write(current_line);
if (!fp) {
msg = "Error opening log file";
goto ret;
int letter;
print_statusline("Mark: ");
- letter = less_getch();
+ letter = less_getch(sizeof("Mark: ") - 1);
if (isalpha(letter)) {
/* If we exceed 15 marks, start overwriting previous ones */
int i;
print_statusline("Go to mark: ");
- letter = less_getch();
+ letter = less_getch(sizeof("Go to mark: ") - 1);
clear_line();
if (isalpha(letter)) {
static char opp_bracket(char bracket)
{
switch (bracket) {
- case '{': case '[':
- return bracket + 2;
- case '(':
- return ')';
- case '}': case ']':
- return bracket - 2;
- case ')':
- return '(';
- }
- return 0;
+ 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)
{
- int bracket_line = -1;
- int i;
+ 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], opp_bracket(bracket)) != NULL) {
- bracket_line = i;
- break;
+ if (strchr(flines[i], bracket) != NULL) {
+ buffer_line(i);
+ return;
}
}
- if (bracket_line == -1)
- print_statusline("No matching bracket found");
- buffer_line(bracket_line - max_displayed_line);
+ print_statusline("No matching bracket found");
}
static void match_left_bracket(char bracket)
{
- int bracket_line = -1;
int i;
if (strchr(flines[cur_fline + max_displayed_line], bracket) == NULL) {
return;
}
+ bracket = opp_bracket(bracket);
for (i = cur_fline + max_displayed_line; i >= 0; i--) {
- if (strchr(flines[i], opp_bracket(bracket)) != NULL) {
- bracket_line = i;
- break;
+ if (strchr(flines[i], bracket) != NULL) {
+ buffer_line(i);
+ return;
}
}
- if (bracket_line == -1)
- print_statusline("No matching bracket found");
- buffer_line(bracket_line);
+ print_statusline("No matching bracket found");
}
#endif /* FEATURE_LESS_BRACKETS */
static void keypress_process(int keypress)
{
switch (keypress) {
- case KEY_DOWN: case 'e': case 'j': case 0x0d:
+ case KEYCODE_DOWN: case 'e': case 'j': case 0x0d:
buffer_down(1);
break;
- case KEY_UP: case 'y': case 'k':
+ case KEYCODE_UP: case 'y': case 'k':
buffer_up(1);
break;
- case PAGE_DOWN: case ' ': case 'z':
+ case KEYCODE_PAGEDOWN: case ' ': case 'z': case 'f':
buffer_down(max_displayed_line + 1);
break;
- case PAGE_UP: case 'w': case 'b':
+ case KEYCODE_PAGEUP: case 'w': case 'b':
buffer_up(max_displayed_line + 1);
break;
case 'd':
case 'u':
buffer_up((max_displayed_line + 1) / 2);
break;
- case KEY_HOME: case 'g': case 'p': case '<': case '%':
+ case KEYCODE_HOME: case 'g': case 'p': case '<': case '%':
buffer_line(0);
break;
- case KEY_END: case 'G': case '>':
+ case KEYCODE_END: case 'G': case '>':
cur_fline = MAXLINES;
read_lines();
buffer_line(cur_fline);
break;
case 'q': case 'Q':
- less_exit(0);
+ less_exit(EXIT_SUCCESS);
break;
#if ENABLE_FEATURE_LESS_MARKS
case 'm':
break;
#endif
case 'r': case 'R':
+ /* TODO: (1) also bind ^R, ^L to this?
+ * (2) re-measure window size?
+ */
buffer_print();
break;
/*case 'R':
regex_process();
break;
#endif
-#if ENABLE_FEATURE_LESS_FLAGCS
+#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);
number_process(keypress);
}
-static void sig_catcher(int sig ATTRIBUTE_UNUSED)
+static void sig_catcher(int sig)
{
- set_tty_cooked();
- exit(1);
+ 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);
+int less_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int less_main(int argc, char **argv)
{
- int keypress;
+ char *tty_name;
+ int tty_fd;
+
+ 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(argc, argv, "EMmN~");
+ getopt32(argv, "EMmN~I" IF_FEATURE_LESS_DASHCMD("S"));
argc -= optind;
argv += optind;
num_files = argc;
bb_error_msg("missing filename");
bb_show_usage();
}
- } else
+ } else {
filename = xstrdup(files[0]);
+ }
+
+ if (option_mask32 & FLAG_TILDE)
+ empty_line_marker = "";
- kbd_fd = xopen(CURRENT_TTY, O_RDONLY);
+ /* Some versions of less can survive w/o controlling tty,
+ * try to do the same. This also allows to specify an alternative
+ * tty via "less 1<>TTY".
+ * We don't try to use STDOUT_FILENO directly,
+ * since we want to set this fd to non-blocking mode,
+ * and not bother with restoring it on exit.
+ */
+ tty_name = xmalloc_ttyname(STDOUT_FILENO);
+ if (tty_name) {
+ tty_fd = open(tty_name, O_RDONLY);
+ free(tty_name);
+ if (tty_fd < 0)
+ goto try_ctty;
+ } else {
+ /* Try controlling tty */
+ try_ctty:
+ tty_fd = open(CURRENT_TTY, O_RDONLY);
+ if (tty_fd < 0)
+ return bb_cat(argv);
+ }
+ ndelay_on(tty_fd);
+ kbd_fd = tty_fd; /* save in a global */
- get_terminal_width_height(kbd_fd, &width, &max_displayed_line);
+ 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)
- bb_error_msg_and_die("too narrow here");
+ return bb_cat(argv);
max_displayed_line -= 2;
- buffer = xmalloc((max_displayed_line+1) * sizeof(char *));
- if (option_mask32 & FLAG_TILDE)
- empty_line_marker = "";
-
- tcgetattr(kbd_fd, &term_orig);
- signal(SIGTERM, sig_catcher);
- signal(SIGINT, sig_catcher);
- term_vi = term_orig;
- term_vi.c_lflag &= ~(ICANON | ECHO);
- term_vi.c_iflag &= ~(IXON | ICRNL);
- /*term_vi.c_oflag &= ~ONLCR;*/
- term_vi.c_cc[VMIN] = 1;
- term_vi.c_cc[VTIME] = 0;
-
- /* Want to do it just once, but it doesn't work, */
- /* so we are redoing it (see code above). Mystery... */
- /*tcsetattr(kbd_fd, TCSANOW, &term_vi);*/
+ /* 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) {
- keypress = less_getch();
+ 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.
+*/
projects / platform / upstream / busybox.git / blobdiff