[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit
Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/app/busybox/src/miscutils/less.c b/ap/app/busybox/src/miscutils/less.c
new file mode 100644
index 0000000..5ce0a12
--- /dev/null
+++ b/ap/app/busybox/src/miscutils/less.c
@@ -0,0 +1,1916 @@
+/* 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 -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
+
+
+#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.
+*/