* TODO:
* - Add more regular expression support - search modifiers, certain matches, etc.
* - Add more complex bracket searching - currently, nested brackets are
- * not considered.
+ * not considered.
* - Add support for "F" as an input. This causes less to act in
- * a similar way to tail -f.
+ * 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
+ * redirected input has been read from stdin
*/
#include "busybox.h"
#include "xregex.h"
#endif
-
-/* These are the escape sequences corresponding to special keys */
-#define REAL_KEY_UP 'A'
-#define REAL_KEY_DOWN 'B'
-#define REAL_KEY_RIGHT 'C'
-#define REAL_KEY_LEFT 'D'
-#define REAL_PAGE_UP '5'
-#define REAL_PAGE_DOWN '6'
-#define REAL_KEY_HOME '7'
-#define REAL_KEY_END '8'
-
-/* These are the special codes assigned by this program to the special keys */
-#define KEY_UP 20
-#define KEY_DOWN 21
-#define KEY_RIGHT 22
-#define KEY_LEFT 23
-#define PAGE_UP 24
-#define PAGE_DOWN 25
-#define KEY_HOME 26
-#define KEY_END 27
+/* FIXME: currently doesn't work right */
+#undef ENABLE_FEATURE_LESS_FLAGCS
+#define ENABLE_FEATURE_LESS_FLAGCS 0
/* The escape codes for highlighted and normal text */
#define HIGHLIGHT "\033[7m"
/* The escape code to clear to end of line */
#define CLEAR_2_EOL "\033[K"
-#define MAXLINES CONFIG_FEATURE_LESS_MAXLINES
+/* 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',
+
+/* 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,
+
+/* 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 int height;
-static int width;
-static char **files;
static char *filename;
+static char **files;
+static unsigned num_files = 1;
+static unsigned current_file = 1;
static const char **buffer;
-static char **flines;
-static int current_file = 1;
-static int line_pos;
-static int num_flines;
-static int num_files = 1;
-static const char *empty_line_marker = "~";
+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 */
-#define FLAG_E 1
-#define FLAG_M (1<<1)
-#define FLAG_m (1<<2)
-#define FLAG_N (1<<3)
-#define FLAG_TILDE (1<<4)
+enum {
+ FLAG_E = 1,
+ FLAG_M = 1 << 1,
+ FLAG_m = 1 << 2,
+ FLAG_N = 1 << 3,
+ FLAG_TILDE = 1 << 4,
/* hijack command line options variable for internal state vars */
-#define LESS_STATE_MATCH_BACKWARDS (1<<6)
+ LESS_STATE_MATCH_BACKWARDS = 1 << 15,
+};
#if ENABLE_FEATURE_LESS_MARKS
-static int mark_lines[15][2];
-static int num_marks;
+static unsigned mark_lines[15][2];
+static unsigned num_marks;
#endif
#if ENABLE_FEATURE_LESS_REGEXP
-static int *match_lines;
-static int match_pos;
-static int num_matches;
+static unsigned *match_lines;
+static int match_pos; /* signed! */
+static unsigned num_matches;
static regex_t pattern;
-static int pattern_valid;
+static unsigned pattern_valid;
+#else
+enum { pattern_valid = 0 };
#endif
-/* Needed termios structures */
static struct termios term_orig, term_vi;
/* File pointer to get input from */
-static FILE *inp;
+static int kbd_fd;
/* Reset terminal input to normal */
static void set_tty_cooked(void)
{
fflush(stdout);
- tcsetattr(fileno(inp), TCSANOW, &term_orig);
+ tcsetattr(kbd_fd, TCSANOW, &term_orig);
}
/* Exit the program gracefully */
-static void tless_exit(int code)
+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? */
-
+ * 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);
}
-/* 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 tless_getch(void)
-{
- int input;
- /* Set terminal input to raw mode (taken from vi.c) */
- tcsetattr(fileno(inp), TCSANOW, &term_vi);
- again:
- input = getc(inp);
- /* Detect escape sequences (i.e. arrow keys) and handle
- them accordingly */
-
- if (input == '\033' && getc(inp) == '[') {
- unsigned i;
- input = getc(inp);
- set_tty_cooked();
-
- i = input - REAL_KEY_UP;
- if (i < 4)
- return 20 + i;
- i = input - REAL_PAGE_UP;
- if (i < 4)
- return 24 + i;
- return 0; /* ?? */
- }
- /* Reject almost all control chars */
- if (input < ' ' && input != 0x0d && input != 8) goto again;
- set_tty_cooked();
- return input;
-}
-
-static char* tless_gets(void)
-{
- int c;
- int i = 0;
- char *result = xzalloc(1);
- while (1) {
- c = tless_getch();
- if (c == 0x0d)
- return result;
- if (c == 0x7f) c = 8;
- if (c == 8 && i) {
- printf("\x8 \x8");
- i--;
- }
- if (c < ' ')
- continue;
- putchar(c);
- result[i++] = c;
- result = xrealloc(result, i+1);
- result[i] = '\0';
- if (i >= width-1) return result;
- }
-}
-
/* 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)
static void clear_line(void)
{
- printf("\033[%u;0H" CLEAR_2_EOL, height);
+ printf("\033[%u;0H" CLEAR_2_EOL, max_displayed_line + 2);
}
static void print_hilite(const char *str)
printf(HIGHLIGHT"%s"NORMAL, str);
}
-static void data_readlines(void)
+static void print_statusline(const char *str)
{
- unsigned i;
- unsigned n = 1;
- int w = width;
- /* "remained unused space" in a line (0 if line fills entire width) */
- int rem, last_rem = 1; /* "not 0" */
- char *current_line, *p;
- FILE *fp;
+ clear_line();
+ printf(HIGHLIGHT"%.*s"NORMAL, width - 1, str);
+}
- fp = filename ? xfopen(filename, "r") : stdin;
- flines = NULL;
- if (option_mask32 & FLAG_N) {
- w -= 6;
+#if ENABLE_FEATURE_LESS_REGEXP
+static void fill_match_lines(unsigned pos);
+#else
+#define fill_match_lines(pos) ((void)0)
+#endif
+
+
+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 (option_mask32 & FLAG_N)
+ w -= 8;
+
+ current_line = xmalloc(w);
+ p = current_line;
+ max_fline += last_terminated;
+ if (!last_terminated) {
+ const char *cp = flines[max_fline];
+ if (option_mask32 & FLAG_N)
+ cp += 8;
+ strcpy(current_line, cp);
+ p += strlen(current_line);
+ } else {
+ linepos = 0;
}
- for (i = 0; !feof(fp) && i <= MAXLINES; i++) {
- flines = xrealloc(flines, (i+1) * sizeof(char *));
- current_line = xmalloc(w);
+
+ while (1) {
again:
- p = current_line;
- rem = w - 1;
- do {
- int c = getc(fp);
- if (c == EOF) break;
- if (c == '\n') break;
+ *p = '\0';
+ terminated = 0;
+ while (1) {
+ char c;
+ if (readpos >= readeof) {
+ ndelay_on(0);
+ eof_error = safe_read(0, 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) {
+ 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') {
+ readpos++; /* eat it */
+ linepos--;
+ *--p = '\0';
+ continue;
+ }
+ if (c == '\t')
+ linepos += (linepos^7) & 7;
+ linepos++;
+ if (linepos >= w)
+ break;
+ /* ok, we will eat this char */
+ readpos++;
+ if (c == '\n') { terminated = 1; break; }
/* NUL is substituted by '\n'! */
if (c == '\0') c = '\n';
*p++ = c;
- } while (--rem);
- *p = '\0';
- if (fp != stdin)
- die_if_ferror(fp, filename);
-
+ *p = '\0';
+ }
/* Corner case: linewrap with only "" wrapping to next line */
/* Looks ugly on screen, so we do not store this empty line */
- if (!last_rem && !current_line[0]) {
- last_rem = 1; /* "not 0" */
- n++;
+ if (!last_terminated && !current_line[0]) {
+ last_terminated = 1;
+ max_lineno++;
goto again;
}
- last_rem = rem;
+ reached_eof:
+ last_terminated = terminated;
+ flines = xrealloc(flines, (max_fline+1) * sizeof(char *));
if (option_mask32 & FLAG_N) {
- flines[i] = xasprintf((n <= 99999) ? "%5u %s" : "%05u %s",
- n % 100000, current_line);
+ /* 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 (rem)
- n++;
+ if (terminated)
+ max_lineno++;
} else {
- flines[i] = xrealloc(current_line, strlen(current_line)+1);
+ flines[max_fline] = xrealloc(current_line, strlen(current_line)+1);
}
+ if (max_fline >= MAXLINES)
+ break;
+ if (max_fline > cur_fline + max_displayed_line)
+ break;
+ 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;
+ }
+ break;
+ }
+ max_fline++;
+ current_line = xmalloc(w);
+ p = current_line;
+ linepos = 0;
}
- num_flines = i - 1; /* buggie: 'num_flines' must be 'max_fline' */
-
- /* Reset variables for a new file */
-
- line_pos = 0;
-
- fclose(fp);
+ fill_match_lines(old_max_fline);
+#undef readbuf
}
#if ENABLE_FEATURE_LESS_FLAGS
-
-/* Interestingly, writing calc_percent as a function and not a prototype saves around 32 bytes
+/* Interestingly, writing calc_percent as a function saves around 32 bytes
* on my build. */
static int calc_percent(void)
{
- return ((100 * (line_pos + height - 2) / num_flines) + 1);
+ 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 */
{
int percentage;
- if (!line_pos) {
- if (num_files > 1) {
- printf(HIGHLIGHT"%s (file %i of %i) lines %i-%i/%i ",
- filename, current_file, num_files,
- line_pos + 1, line_pos + height - 1, num_flines + 1);
- } else {
- printf(HIGHLIGHT"%s lines %i-%i/%i ",
- filename, line_pos + 1, line_pos + height - 1,
- num_flines + 1);
- }
- } else {
- printf(HIGHLIGHT" %s lines %i-%i/%i ", filename,
- line_pos + 1, line_pos + height - 1, num_flines + 1);
- }
-
- if (line_pos >= num_flines - height + 2) {
- printf("(END) "NORMAL);
+ 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 >= max_fline - max_displayed_line) {
+ printf("(END)"NORMAL);
if (num_files > 1 && current_file != num_files)
- printf(HIGHLIGHT"- Next: %s"NORMAL, files[current_file]);
- } else {
- percentage = calc_percent();
- printf("%i%% "NORMAL, percentage);
+ printf(HIGHLIGHT" - next: %s"NORMAL, files[current_file]);
+ return;
}
-}
-
-/* Print a status line if -m was specified */
-static void medium_status_print(void)
-{
- int percentage;
percentage = calc_percent();
-
- if (!line_pos)
- printf(HIGHLIGHT"%s %i%%"NORMAL, filename, percentage);
- else if (line_pos == num_flines - height + 2)
- print_hilite("(END)");
- else
- printf(HIGHLIGHT"%i%%"NORMAL, percentage);
+ printf("%i%%"NORMAL, percentage);
}
#endif
/* Print the status line */
static void status_print(void)
{
+ const char *p;
+
/* Change the status if flags have been set */
#if ENABLE_FEATURE_LESS_FLAGS
- if (option_mask32 & FLAG_M)
+ if (option_mask32 & (FLAG_M|FLAG_m)) {
m_status_print();
- else if (option_mask32 & FLAG_m)
- medium_status_print();
+ return;
+ }
/* No flags set */
- else {
#endif
- if (!line_pos) {
- print_hilite(filename);
- if (num_files > 1)
- printf(HIGHLIGHT"(file %i of %i)"NORMAL,
- current_file, num_files);
- } else if (line_pos == num_flines - height + 2) {
- print_hilite("(END) ");
- if (num_files > 1 && current_file != num_files)
- printf(HIGHLIGHT"- Next: %s"NORMAL, files[current_file]);
- } else {
- putchar(':');
- }
-#if ENABLE_FEATURE_LESS_FLAGS
+
+ clear_line();
+ if (cur_fline && cur_fline < max_fline - max_displayed_line) {
+ putchar(':');
+ return;
}
-#endif
+ 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 char controls[] =
- /**/"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f"
+ /* 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[] =
- /* Note that on input NUL is converted to '\n' ('\x0a') */
- /* Therefore we subst '\n' with '@', not 'J' */
+ /* '\n': it's a former NUL - subst 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";
+#if ENABLE_FEATURE_LESS_REGEXP
static void print_found(const char *line)
{
int match_status;
}
if (!growline) {
- printf("%s"CLEAR_2_EOL"\n", str);
+ printf(CLEAR_2_EOL"%s\n", str);
return;
}
- printf("%s%s"CLEAR_2_EOL"\n", growline, str);
+ printf(CLEAR_2_EOL"%s%s\n", growline, str);
free(growline);
}
+#else
+void print_found(const char *line);
+#endif
static void print_ascii(const char *str)
{
char *p;
size_t n;
+ printf(CLEAR_2_EOL);
while (*str) {
n = strcspn(str, controls);
if (n) {
if (!str[n]) break;
- printf("%.*s", n, str);
+ printf("%.*s", (int) n, str);
str += n;
}
n = strspn(str, controls);
do {
if (*str == 0x7f)
*p++ = '?';
- else if (*str == 0x9b)
+ else if (*str == (char)0x9b)
/* VT100's CSI, aka Meta-ESC. Who's inventor? */
/* I want to know who committed this sin */
*p++ = '{';
*p = '\0';
print_hilite(buf);
}
- printf("%s"CLEAR_2_EOL"\n", str);
+ puts(str);
}
/* Print the buffer */
int i;
move_cursor(0, 0);
- for (i = 0; i < height - 1; i++)
+ for (i = 0; i <= max_displayed_line; i++)
if (pattern_valid)
print_found(buffer[i]);
else
print_ascii(buffer[i]);
- fputs(CLEAR_2_EOL, stdout); /* clears status line */
status_print();
}
-/* Initialise the buffer */
-static void buffer_init(void)
+static void buffer_fill_and_print(void)
{
int i;
-
- /* Fill the buffer until the end of the file or the
- end of the buffer is reached */
- for (i = 0; i < height - 1 && i <= num_flines; i++) {
- buffer[i] = flines[i];
+ for (i = 0; i <= max_displayed_line && cur_fline + i <= max_fline; i++) {
+ buffer[i] = flines[cur_fline + i];
}
-
- /* If the buffer still isn't full, fill it with blank lines */
- for (; i < height - 1; i++) {
+ 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)
{
- int i;
+ int diff;
+ cur_fline += nlines;
+ read_lines();
- if (line_pos + (height - 3) + nlines < num_flines) {
- line_pos += nlines;
- for (i = 0; i < (height - 1); i++) {
- buffer[i] = flines[line_pos + i];
- }
- } else {
+ if (cur_fline + max_displayed_line > max_fline + TILDES) {
+ cur_fline -= nlines;
+ 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 */
- while (line_pos + (height - 3) + 1 < num_flines) {
- line_pos += 1;
- for (i = 0; i < (height - 1); i++) {
- buffer[i] = flines[line_pos + i];
- }
- }
+ if (diff > 0)
+ cur_fline += diff;
}
-
- /* We exit if the -E flag has been set */
- if ((option_mask32 & FLAG_E) && (line_pos + (height - 2) == num_flines))
- tless_exit(0);
+ buffer_fill_and_print();
}
static void buffer_up(int nlines)
{
- int i;
+ cur_fline -= nlines;
+ if (cur_fline < 0) cur_fline = 0;
+ read_lines();
+ buffer_fill_and_print();
+}
- line_pos -= nlines;
- if (line_pos < 0) line_pos = 0;
- for (i = 0; i < height - 1; i++) {
- if (line_pos + i <= num_flines) {
- buffer[i] = flines[line_pos + i];
- } else {
- buffer[i] = empty_line_marker;
- }
+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;
+ cur_fline = linenum;
+ buffer_fill_and_print();
+}
+
+static void open_file_and_read_lines(void)
+{
+ if (filename) {
+ int fd = xopen(filename, O_RDONLY);
+ dup2(fd, 0);
+ if (fd) close(fd);
+ } else {
+ /* "less" with no arguments in argv[] */
+ /* For status line only */
+ filename = xstrdup(bb_msg_standard_input);
}
+ readpos = 0;
+ readeof = 0;
+ linepos = 0;
+ terminated = 1;
+ read_lines();
}
-static void buffer_line(int linenum)
+/* Reinitialize everything for a new file - free the memory and start over */
+static void reinitialize(void)
{
int i;
- if (linenum < 0 || linenum > num_flines) {
- clear_line();
- printf(HIGHLIGHT"%s%u"NORMAL, "Cannot seek to line ", linenum + 1);
- return;
+ if (flines) {
+ for (i = 0; i <= max_fline; i++)
+ free((void*)(flines[i]));
+ free(flines);
+ flines = NULL;
}
- for (i = 0; i < height - 1; i++) {
- if (linenum + i <= num_flines)
- buffer[i] = flines[linenum + i];
- else {
- buffer[i] = empty_line_marker;
- }
+ max_fline = -1;
+ cur_fline = 0;
+ max_lineno = 0;
+ open_file_and_read_lines();
+ buffer_fill_and_print();
+}
+
+static void getch_nowait(char* input, int sz)
+{
+ ssize_t rd;
+ fd_set readfds;
+ 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
+ * (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 */
+ ) {
+ /* We are interested in stdin */
+ FD_SET(0, &readfds);
+ }
+ 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;
}
- line_pos = linenum;
- buffer_print();
}
-/* Reinitialise everything for a new file - free the memory and start over */
-static void reinitialise(void)
+/* 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)
{
- int i;
+ char input[16];
+ unsigned i;
+ again:
+ getch_nowait(input, sizeof(input));
+ /* Detect escape sequences (i.e. arrow keys) and handle
+ * them accordingly */
- for (i = 0; i <= num_flines; i++)
- free(flines[i]);
- free(flines);
+ 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;
+ return 0;
+ }
+ /* Reject almost all control chars */
+ i = input[0];
+ if (i < ' ' && i != 0x0d && i != 8) goto again;
+ set_tty_cooked();
+ return i;
+}
- data_readlines();
- buffer_init();
- buffer_print();
+static char* less_gets(int sz)
+{
+ char c;
+ int 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)
+ return result;
+ if (c == 0x7f)
+ c = 8;
+ if (c == 8 && i) {
+ printf("\x8 \x8");
+ i--;
+ }
+ if (c < ' ')
+ continue;
+ if (i >= width - sz - 1)
+ continue; /* len limit */
+ putchar(c);
+ result[i++] = c;
+ result = xrealloc(result, i+1);
+ result[i] = '\0';
+ }
}
static void examine_file(void)
{
- clear_line();
- printf("Examine: ");
+ print_statusline("Examine: ");
free(filename);
- filename = tless_gets();
+ filename = less_gets(sizeof("Examine: ")-1);
/* 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;
- current_file = 1;
- reinitialise();
+ 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
-*/
+ * 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]);
- reinitialise();
+ reinitialize();
} else {
- clear_line();
- print_hilite((direction > 0) ? "No next file" : "No previous file");
+ print_statusline(direction > 0 ? "No next file" : "No previous file");
}
}
{
int 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--;
- buffer_print();
} else {
change_file(1);
for (i = 2; i <= num_files; i++)
files[i - 2] = files[i - 1];
num_files--;
current_file--;
- buffer_print();
}
}
int keypress;
/* Clear the current line and print a prompt */
- clear_line();
- printf(" :");
+ print_statusline(" :");
- keypress = tless_getch();
+ keypress = less_getch();
switch (keypress) {
- case 'd':
- remove_current_file();
- break;
- case 'e':
- examine_file();
- break;
+ case 'd':
+ remove_current_file();
+ break;
+ case 'e':
+ examine_file();
+ break;
#if ENABLE_FEATURE_LESS_FLAGS
- case 'f':
- clear_line();
- m_status_print();
- break;
+ case 'f':
+ m_status_print();
+ break;
#endif
- case 'n':
- change_file(1);
- break;
- case 'p':
- change_file(-1);
- break;
- case 'q':
- tless_exit(0);
- break;
- case 'x':
- change_file(0);
- break;
- default:
- break;
+ case 'n':
+ change_file(1);
+ break;
+ case 'p':
+ change_file(-1);
+ break;
+ case 'q':
+ less_exit(0);
+ break;
+ case 'x':
+ change_file(0);
+ break;
}
}
+#if ENABLE_FEATURE_LESS_REGEXP
static int normalize_match_pos(int match)
{
match_pos = match;
- if (match < 0)
- return (match_pos = 0);
if (match >= num_matches)
-{
match_pos = num_matches - 1;
-}
+ if (match < 0)
+ match_pos = 0;
return match_pos;
}
-#if ENABLE_FEATURE_LESS_REGEXP
static void goto_match(int match)
{
- buffer_line(match_lines[normalize_match_pos(match)]);
+ if (num_matches)
+ buffer_line(match_lines[normalize_match_pos(match)]);
+}
+
+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(match_lines, (num_matches+1) * sizeof(int));
+ match_lines[num_matches++] = pos;
+ }
+ pos++;
+ }
}
static void regex_process(void)
char *uncomp_regex, *err;
/* Reset variables */
- match_lines = xrealloc(match_lines, sizeof(int));
- match_lines[0] = -1;
+ free(match_lines);
+ match_lines = NULL;
match_pos = 0;
num_matches = 0;
if (pattern_valid) {
/* Get the uncompiled regular expression from the user */
clear_line();
putchar((option_mask32 & LESS_STATE_MATCH_BACKWARDS) ? '?' : '/');
- uncomp_regex = tless_gets();
- if (/*!uncomp_regex ||*/ !uncomp_regex[0]) {
+ uncomp_regex = less_gets(1);
+ if (!uncomp_regex[0]) {
free(uncomp_regex);
buffer_print();
return;
err = regcomp_or_errmsg(&pattern, uncomp_regex, 0);
free(uncomp_regex);
if (err) {
- clear_line();
- fputs(err, stdout);
+ print_statusline(err);
free(err);
return;
}
pattern_valid = 1;
+ match_pos = 0;
- /* Run the regex on each line of the current file */
- for (match_pos = 0; match_pos <= num_flines; match_pos++) {
- if (regexec(&pattern, flines[match_pos], 0, NULL, 0) == 0) {
- match_lines = xrealloc(match_lines, (num_matches+1) * sizeof(int));
- match_lines[num_matches++] = match_pos;
- }
- }
+ fill_match_lines(0);
- if (num_matches == 0 || num_flines <= height - 2) {
+ if (num_matches == 0 || max_fline <= max_displayed_line) {
buffer_print();
return;
}
- for (match_pos = 0; match_pos < num_matches; match_pos++) {
- if (match_lines[match_pos] > line_pos)
+ while (match_pos < num_matches) {
+ if (match_lines[match_pos] > cur_fline)
break;
+ match_pos++;
}
- if (option_mask32 & LESS_STATE_MATCH_BACKWARDS) match_pos--;
+ if (option_mask32 & LESS_STATE_MATCH_BACKWARDS)
+ match_pos--;
buffer_line(match_lines[normalize_match_pos(match_pos)]);
}
#endif
/* Receive input until a letter is given */
while (i < sizeof(num_input)-1) {
- num_input[i] = tless_getch();
+ num_input[i] = less_getch();
if (!num_input[i] || !isdigit(num_input[i]))
break;
putchar(num_input[i]);
/* 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':
- buffer_down(num);
- break;
- case KEY_UP: case 'b': case 'w': case 'y': case 'u':
- buffer_up(num);
- break;
- case 'g': case '<': case 'G': case '>':
- if (num_flines >= height - 2)
- buffer_line(num - 1);
- break;
- case 'p': case '%':
- buffer_line(((num / 100) * num_flines) - 1);
- break;
+ case KEY_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':
+ 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;
+ 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
- default:
- break;
}
}
clear_line();
putchar('-');
- keypress = tless_getch();
+ keypress = less_getch();
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;
- default:
- break;
+ 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;
}
}
clear_line();
putchar('_');
- keypress = tless_getch();
+ keypress = less_getch();
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;
+ 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"%s%u"NORMAL, "The status of the flag is: ", flag_val != 0);
+ printf(HIGHLIGHT"The status of the flag is: %u"NORMAL, flag_val != 0);
}
#endif
-static void full_repaint(void)
-{
- int temp_line_pos = line_pos;
- data_readlines();
- buffer_init();
- buffer_line(temp_line_pos);
-}
-
-
static void save_input_to_file(void)
{
+ const char *msg = "";
char *current_line;
int i;
FILE *fp;
- clear_line();
- printf("Log file: ");
- current_line = tless_gets();
+ print_statusline("Log file: ");
+ current_line = less_gets(sizeof("Log file: ")-1);
if (strlen(current_line) > 0) {
fp = fopen(current_line, "w");
- free(current_line);
if (!fp) {
- print_hilite("Error opening log file");
- return;
+ msg = "Error opening log file";
+ goto ret;
}
- for (i = 0; i < num_flines; i++)
+ for (i = 0; i <= max_fline; i++)
fprintf(fp, "%s\n", flines[i]);
fclose(fp);
- buffer_print();
- return;
+ msg = "Done";
}
+ ret:
+ print_statusline(msg);
free(current_line);
- print_hilite("No log file");
}
#if ENABLE_FEATURE_LESS_MARKS
{
int letter;
- clear_line();
- printf("Mark: ");
- letter = tless_getch();
+ print_statusline("Mark: ");
+ letter = less_getch();
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] = line_pos;
+ mark_lines[num_marks][1] = cur_fline;
num_marks++;
} else {
- clear_line();
- print_hilite("Invalid mark letter");
+ print_statusline("Invalid mark letter");
}
}
int letter;
int i;
- clear_line();
- printf("Go to mark: ");
- letter = tless_getch();
+ print_statusline("Go to mark: ");
+ letter = less_getch();
clear_line();
if (isalpha(letter)) {
break;
}
if (num_marks == 14 && letter != mark_lines[14][0])
- print_hilite("Mark not set");
+ print_statusline("Mark not set");
} else
- print_hilite("Invalid mark letter");
+ print_statusline("Invalid mark letter");
}
#endif
-
#if ENABLE_FEATURE_LESS_BRACKETS
-
static char opp_bracket(char bracket)
{
switch (bracket) {
- case '{': case '[':
- return bracket + 2;
- case '(':
- return ')';
- case '}': case ']':
- return bracket - 2;
- case ')':
- return '(';
- default:
- return 0;
+ case '{': case '[':
+ return bracket + 2;
+ case '(':
+ return ')';
+ case '}': case ']':
+ return bracket - 2;
+ case ')':
+ return '(';
}
+ return 0;
}
static void match_right_bracket(char bracket)
int bracket_line = -1;
int i;
- clear_line();
-
- if (strchr(flines[line_pos], bracket) == NULL) {
- print_hilite("No bracket in top line");
+ if (strchr(flines[cur_fline], bracket) == NULL) {
+ print_statusline("No bracket in top line");
return;
}
- for (i = line_pos + 1; i < num_flines; i++) {
+ for (i = cur_fline + 1; i < max_fline; i++) {
if (strchr(flines[i], opp_bracket(bracket)) != NULL) {
bracket_line = i;
break;
}
}
if (bracket_line == -1)
- print_hilite("No matching bracket found");
- buffer_line(bracket_line - height + 2);
+ print_statusline("No matching bracket found");
+ buffer_line(bracket_line - max_displayed_line);
}
static void match_left_bracket(char bracket)
int bracket_line = -1;
int i;
- clear_line();
-
- if (strchr(flines[line_pos + height - 2], bracket) == NULL) {
- print_hilite("No bracket in bottom line");
- /* ?? */
- /*printf("%s", flines[line_pos + height]);*/
- /*sleep(4);*/
+ if (strchr(flines[cur_fline + max_displayed_line], bracket) == NULL) {
+ print_statusline("No bracket in bottom line");
return;
}
- for (i = line_pos + height - 2; i >= 0; i--) {
+ for (i = cur_fline + max_displayed_line; i >= 0; i--) {
if (strchr(flines[i], opp_bracket(bracket)) != NULL) {
bracket_line = i;
break;
}
}
if (bracket_line == -1)
- print_hilite("No matching bracket found");
+ print_statusline("No matching bracket found");
buffer_line(bracket_line);
}
-
#endif /* FEATURE_LESS_BRACKETS */
static void keypress_process(int keypress)
{
switch (keypress) {
- case KEY_DOWN: case 'e': case 'j': case 0x0d:
- buffer_down(1);
- buffer_print();
- break;
- case KEY_UP: case 'y': case 'k':
- buffer_up(1);
- buffer_print();
- break;
- case PAGE_DOWN: case ' ': case 'z':
- buffer_down(height - 1);
- buffer_print();
- break;
- case PAGE_UP: case 'w': case 'b':
- buffer_up(height - 1);
- buffer_print();
- break;
- case 'd':
- buffer_down((height - 1) / 2);
- buffer_print();
- break;
- case 'u':
- buffer_up((height - 1) / 2);
- buffer_print();
- break;
- case KEY_HOME: case 'g': case 'p': case '<': case '%':
- buffer_line(0);
- break;
- case KEY_END: case 'G': case '>':
- buffer_line(num_flines - height + 2);
- break;
- case 'q': case 'Q':
- tless_exit(0);
- break;
+ case KEY_DOWN: case 'e': case 'j': case 0x0d:
+ buffer_down(1);
+ break;
+ case KEY_UP: case 'y': case 'k':
+ buffer_up(1);
+ break;
+ case PAGE_DOWN: case ' ': case 'z':
+ buffer_down(max_displayed_line + 1);
+ break;
+ case PAGE_UP: 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 KEY_HOME: case 'g': case 'p': case '<': case '%':
+ buffer_line(0);
+ break;
+ case KEY_END: case 'G': case '>':
+ cur_fline = MAXLINES;
+ read_lines();
+ buffer_line(cur_fline);
+ break;
+ case 'q': case 'Q':
+ less_exit(0);
+ break;
#if ENABLE_FEATURE_LESS_MARKS
- case 'm':
- add_mark();
- buffer_print();
- break;
- case '\'':
- goto_mark();
- buffer_print();
- break;
+ case 'm':
+ add_mark();
+ buffer_print();
+ break;
+ case '\'':
+ goto_mark();
+ buffer_print();
+ break;
#endif
- case 'r':
- buffer_print();
- break;
- case 'R':
- full_repaint();
- break;
- case 's':
- save_input_to_file();
- break;
- case 'E':
- examine_file();
- break;
+ case 'r': case 'R':
+ 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 '=':
- clear_line();
- m_status_print();
- break;
+ 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;
+ 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_FLAGCS
- case '-':
- flag_change();
- buffer_print();
- break;
- case '_':
- show_flag_status();
- break;
+ case '-':
+ flag_change();
+ buffer_print();
+ break;
+ case '_':
+ show_flag_status();
+ break;
#endif
#if ENABLE_FEATURE_LESS_BRACKETS
- case '{': case '(': case '[':
- match_right_bracket(keypress);
- break;
- case '}': case ')': case ']':
- match_left_bracket(keypress);
- break;
+ case '{': case '(': case '[':
+ match_right_bracket(keypress);
+ break;
+ case '}': case ')': case ']':
+ match_left_bracket(keypress);
+ break;
#endif
- case ':':
- colon_process();
- break;
- default:
- break;
+ case ':':
+ colon_process();
+ break;
}
if (isdigit(keypress))
exit(1);
}
+int less_main(int argc, char **argv);
int less_main(int argc, char **argv)
{
int keypress;
+ /* 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~");
argc -= optind;
argv += optind;
- files = argv;
num_files = argc;
+ files = argv;
/* Another popular pager, most, detects when stdout
* is not a tty and turns into cat. This makes sense. */
} else
filename = xstrdup(files[0]);
- inp = xfopen(CURRENT_TTY, "r");
+ kbd_fd = xopen(CURRENT_TTY, O_RDONLY);
- get_terminal_width_height(fileno(inp), &width, &height);
- if (width < 10 || height < 3)
+ 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");
+ max_displayed_line -= 2;
- buffer = xmalloc(height * sizeof(char *));
+ buffer = xmalloc((max_displayed_line+1) * sizeof(char *));
if (option_mask32 & FLAG_TILDE)
empty_line_marker = "";
- data_readlines();
-
- tcgetattr(fileno(inp), &term_orig);
+ 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_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;
- buffer_init();
- buffer_print();
+ /* 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);*/
+ reinitialize();
while (1) {
- keypress = tless_getch();
+ keypress = less_getch();
keypress_process(keypress);
}
}
projects / oweals / busybox.git / blobdiff