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Diffstat (limited to 'miscutils/less.c')
| -rw-r--r-- | miscutils/less.c | 1262 |
1 files changed, 1262 insertions, 0 deletions
diff --git a/miscutils/less.c b/miscutils/less.c new file mode 100644 index 000000000..43bc6737e --- /dev/null +++ b/miscutils/less.c @@ -0,0 +1,1262 @@ +/* vi: set sw=4 ts=4: */ +/* + * Mini less implementation for busybox + * + * + * Copyright (C) 2005 by Rob Sullivan <cogito.ergo.cogito@gmail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + * 02111-1307 USA + * + * This program needs a lot of development, so consider it in a beta stage + * at best. + * + * 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. + * - Check for binary files, and prompt the user if a binary file + * is detected. + * - Allow horizontal scrolling. Currently, lines simply continue onto + * the next line, per the terminal's discretion + * + * Notes: + * - filename is an array and not a pointer because that avoids all sorts + * of complications involving the fact that something that is pointed to + * will be changed if the pointer is changed. + * - the inp file pointer is used so that keyboard input works after + * redirected input has been read from stdin +*/ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <termios.h> +#include <unistd.h> +#include <regex.h> +#include <ctype.h> +#include "busybox.h" + +/* 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' + +/* These are the special codes assigned by this program to the special keys */ +#define PAGE_UP 20 +#define PAGE_DOWN 21 +#define KEY_UP 22 +#define KEY_DOWN 23 +#define KEY_RIGHT 24 +#define KEY_LEFT 25 + +/* 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[2J" + +/* Maximum number of lines in a file */ +#define MAXLINES 10000 + +/* Get height and width of terminal */ +#define tty_width_height() get_terminal_width_height(0, &width, &height) + +/* Function prototypes */ +static void set_tty_cooked(void); +static void set_tty_raw(void); +static void tless_exit(int code); +static int tless_getch(void); +static void move_cursor(int x, int y); +static void clear_line(void); +static void data_readlines(void); +static void free_flines(void); +#ifdef CONFIG_FEATURE_LESS_FLAGS +static int calc_percent(void); +#endif +static int reverse_percent(int percentage); +#ifdef CONFIG_FEATURE_LESS_FLAGS +static void m_status_print(void); +static void medium_status_print(void); +#endif +static void status_print(void); +static void buffer_print(void); +static void buffer_init(void); +static void buffer_down(int nlines); +static void buffer_up(int nlines); +static void buffer_line(int linenum); +static void keypress_process(int keypress); +static void colon_process(void); +static void number_process(int first_digit); +#ifdef CONFIG_FEATURE_LESS_FLAGCS +static void flag_change(void); +static void show_flag_status(void); +#endif +static void examine_file(void); +static void next_file(void); +static void previous_file(void); +static void first_file(void); +static void remove_current_file(void); +static void full_repaint(void); +static void add_linenumbers(void); +static void save_input_to_file(void); +#ifdef CONFIG_FEATURE_LESS_MARKS +static void add_mark(void); +static void goto_mark(void); +#endif +#ifdef CONFIG_FEATURE_LESS_REGEXP +static void regex_process(void); +char *process_regex_on_line(char *line, regex_t *pattern); +char *insert_highlights(char *line, int start, int end); +static void goto_match (int match); +static void search_backwards(void); +#endif +#ifdef CONFIG_FEATURE_LESS_BRACKETS +static char opp_bracket (char bracket); +static void match_right_bracket (char bracket); +static void match_left_bracket (char bracket); +#endif +int less_main(int argc, char *argv[]); + +static int height; +static int width; +static char **files; +static char filename[256]; +static char buffer[100][256]; +static char *flines[MAXLINES]; +static int current_file = 1; +static int line_pos = 0; +static int num_flines; +static int num_files = 1; +static int past_eof = 0; + +/* Command line options */ +static int E_FLAG = 0; +static int M_FLAG = 0; +static int N_FLAG = 0; +static int m_FLAG = 0; +static int TILDE_FLAG = 0; + +/* This is needed so that program behaviour changes when input comes from + stdin */ +static int inp_stdin = 0; +/* This is required so that when a file is requested to be examined after + input has come from stdin (e.g. dmesg | less), the input stream from + the keyboard still stays the same. If it switched back to stdin, keyboard + input wouldn't work. */ +static int ea_inp_stdin = 0; + +#ifdef CONFIG_FEATURE_LESS_MARKS +static int mark_lines[15][2]; +static int num_marks = 0; +#endif + +#ifdef CONFIG_FEATURE_LESS_REGEXP +static int match_found = 0; +static int match_lines[100]; +static int match_pos = 0; +static int num_matches = 0; +static int match_backwards = 0; +static int num_back_match = 1; +#endif + +/* Needed termios structures */ +static struct termios term_orig, term_vi; + +/* File pointer to get input from */ +static FILE *inp; + +/* Reset terminal input to normal */ +static void set_tty_cooked() { + fflush(stdout); + tcsetattr(0, TCSANOW, &term_orig); +} + +/* Set terminal input to raw mode */ +static void set_tty_raw() { + tcgetattr(0, &term_orig); + 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; + tcsetattr(0, TCSANOW, &term_vi); +} + +/* Exit the program gracefully */ +static void tless_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'); + 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. */ +int tless_getch() { + + set_tty_raw(); + char input_key[3]; + + input_key[0] = getc(inp); + /* Detect escape sequences (i.e. arrow keys) and handle + them accordingly */ + + if (input_key[0] == '\033') { + input_key[1] = getc(inp); + input_key[2] = getc(inp); + set_tty_cooked(); + if (input_key[1] == '[') { + if (input_key[2] == REAL_KEY_UP) + return KEY_UP; + else if (input_key[2] == REAL_KEY_DOWN) + return KEY_DOWN; + else if (input_key[2] == REAL_KEY_RIGHT) + return KEY_RIGHT; + else if (input_key[2] == REAL_KEY_LEFT) + return KEY_LEFT; + else if (input_key[2] == REAL_PAGE_UP) + return PAGE_UP; + else if (input_key[2] == REAL_PAGE_DOWN) + return PAGE_DOWN; + } + } + /* The input is a normal ASCII value */ + else { + set_tty_cooked(); + return input_key[0]; + } + return 0; +} + +/* Move the cursor to a position (x,y), where (0,0) is the + top-left corner of the console */ +static void move_cursor(int x, int y) { + printf("\033[%i;%iH", x, y); +} + +static void clear_line() { + move_cursor(height, 0); + printf("\033[K"); +} + +static void data_readlines() { + + int i; + char current_line[256]; + FILE *fp; + + fp = (inp_stdin) ? stdin : bb_xfopen(filename, "rt"); + + for (i = 0; (!feof(fp)) && (i <= MAXLINES); i++) { + strcpy(current_line, ""); + fgets(current_line, 256, fp); + bb_xferror(fp, filename); + flines[i] = (char *) bb_xstrndup(current_line, (strlen(current_line) + 1) * sizeof(char)); + } + num_flines = i - 2; + +/* Reset variables for a new file */ + + line_pos = 0; + past_eof = 0; + + fclose(fp); + + if (inp_stdin) + inp = fopen(CURRENT_TTY, "r"); + else + inp = stdin; + + if (ea_inp_stdin) { + fclose(inp); + inp = fopen(CURRENT_TTY, "r"); + } + + if (N_FLAG) + add_linenumbers(); +} + +/* Free the file data */ +static void free_flines() { + + int i; + + for (i = 0; i <= num_flines; i++) + free(flines[i]); +} + +#ifdef CONFIG_FEATURE_LESS_FLAGS +/* Calculate the percentage the current line position is through the file */ +int calc_percent() { + return ((100 * (line_pos + height - 2) / num_flines) + 1); +} +#endif + +/* Turn a percentage into a line number */ +int reverse_percent(int percentage) { + double linenum = percentage; + linenum = ((linenum / 100) * num_flines) - 1; + return(linenum); +} + +#ifdef CONFIG_FEATURE_LESS_FLAGS +/* Print a status line if -M was specified */ +static void m_status_print() { + + int percentage; + + if (!past_eof) { + if (!line_pos) { + if (num_files > 1) + printf("%s%s %s%i%s%i%s%i-%i/%i ", HIGHLIGHT, filename, "(file ", current_file, " of ", num_files, ") lines ", line_pos + 1, line_pos + height - 1, num_flines + 1); + else { + printf("%s%s lines %i-%i/%i ", HIGHLIGHT, filename, line_pos + 1, line_pos + height - 1, num_flines + 1); + } + } + else { + printf("%s %s lines %i-%i/%i ", HIGHLIGHT, filename, line_pos + 1, line_pos + height - 1, num_flines + 1); + } + + if (line_pos == num_flines - height + 2) { + printf("(END) %s", NORMAL); + if ((num_files > 1) && (current_file != num_files)) + printf("%s- Next: %s%s", HIGHLIGHT, files[current_file], NORMAL); + } + else { + percentage = calc_percent(); + printf("%i%s %s", percentage, "%", NORMAL); + } + } + else { + printf("%s%s lines %i-%i/%i (END) ", HIGHLIGHT, filename, line_pos + 1, num_flines + 1, num_flines + 1); + if ((num_files > 1) && (current_file != num_files)) + printf("- Next: %s", files[current_file]); + printf("%s", NORMAL); + } +} + +/* Print a status line if -m was specified */ +static void medium_status_print() { + + int percentage; + percentage = calc_percent(); + + if (!line_pos) + printf("%s%s %i%s%s", HIGHLIGHT, filename, percentage, "%", NORMAL); + else if (line_pos == num_flines - height + 2) + printf("%s(END)%s", HIGHLIGHT, NORMAL); + else + printf("%s%i%s%s", HIGHLIGHT, percentage, "%", NORMAL); +} +#endif + +/* Print the status line */ +static void status_print() { + + /* Change the status if flags have been set */ +#ifdef CONFIG_FEATURE_LESS_FLAGS + if (M_FLAG) + m_status_print(); + else if (m_FLAG) + medium_status_print(); + /* No flags set */ + else { +#endif + if (!line_pos) { + printf("%s%s %s", HIGHLIGHT, filename, NORMAL); + if (num_files > 1) + printf("%s%s%i%s%i%s%s", HIGHLIGHT, "(file ", current_file, " of ", num_files, ")", NORMAL); + } + else if (line_pos == num_flines - height + 2) { + printf("%s%s %s", HIGHLIGHT, "(END)", NORMAL); + if ((num_files > 1) && (current_file != num_files)) + printf("%s%s%s%s", HIGHLIGHT, "- Next: ", files[current_file], NORMAL); + } + else { + printf("%c", ':'); + } +#ifdef CONFIG_FEATURE_LESS_FLAGS + } +#endif +} + +/* Print the buffer */ +static void buffer_print() { + + int i; + + if (num_flines >= height - 2) { + printf("%s", CLEAR); + move_cursor(0,0); + for (i = 0; i < height - 1; i++) + printf("%s", buffer[i]); + status_print(); + } + else { + printf("%s", CLEAR); + move_cursor(0,0); + for (i = 1; i < (height - 1 - num_flines); i++) + putchar('\n'); + for (i = 0; i < height - 1; i++) + printf("%s", buffer[i]); + status_print(); + } +} + +/* Initialise the buffer */ +static void buffer_init() { + + int i; + + for (i = 0; i < (height - 1); i++) + memset(buffer[i], '\0', 256); + + /* 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++) { + strcpy(buffer[i], flines[i]); + } + + /* If the buffer still isn't full, fill it with blank lines */ + for (; i < (height - 1); i++) { + strcpy(buffer[i], ""); + } +} + +/* Move the buffer up and down in the file in order to scroll */ +static void buffer_down(int nlines) { + + int i; + + if (!past_eof) { + if (line_pos + (height - 3) + nlines < num_flines) { + line_pos += nlines; + for (i = 0; i < (height - 1); i++) + strcpy(buffer[i], flines[line_pos + i]); + } + else { + /* 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++) + strcpy(buffer[i], flines[line_pos + i]); + } + } + + /* We exit if the -E flag has been set */ + if (E_FLAG && (line_pos + (height - 2) == num_flines)) + tless_exit(0); + } +} + +static void buffer_up(int nlines) { + + int i; + int tilde_line; + + if (!past_eof) { + if (line_pos - nlines >= 0) { + line_pos -= nlines; + for (i = 0; i < (height - 1); i++) + strcpy(buffer[i], flines[line_pos + i]); + } + else { + /* As the requested number of lines to move was too large, we + move one line up at a time until we can't. */ + while (line_pos != 0) { + line_pos -= 1; + for (i = 0; i < (height - 1); i++) + strcpy(buffer[i], flines[line_pos + i]); + } + } + } + else { + /* Work out where the tildes start */ + tilde_line = num_flines - line_pos + 3; + + line_pos -= nlines; + /* Going backwards nlines lines has taken us to a point where + nothing is past the EOF, so we revert to normal. */ + if (line_pos < num_flines - height + 3) { + past_eof = 0; + buffer_up(nlines); + } + else { + /* We only move part of the buffer, as the rest + is past the EOF */ + for (i = 0; i < (height - 1); i++) { + if (i < tilde_line - nlines + 1) + strcpy(buffer[i], flines[line_pos + i]); + else { + if (line_pos >= num_flines - height + 2) + strcpy(buffer[i], "~\n"); + } + } + } + } +} + +static void buffer_line(int linenum) { + + int i; + + past_eof = 0; + + if (linenum < 1 || linenum > num_flines) { + clear_line(); + printf("%s%s%i%s", HIGHLIGHT, "Cannot seek to line number ", linenum, NORMAL); + } + else if (linenum < (num_flines - height - 2)) { + for (i = 0; i < (height - 1); i++) + strcpy(buffer[i], flines[linenum + i]); + line_pos = linenum; + } + else { + for (i = 0; i < (height - 1); i++) { + if (linenum + i < num_flines + 2) + strcpy(buffer[i], flines[linenum + i]); + else + strcpy(buffer[i], (TILDE_FLAG) ? "\n" : "~\n"); + } + line_pos = linenum; + /* Set past_eof so buffer_down and buffer_up act differently */ + past_eof = 1; + } +} + +static void keypress_process(int keypress) { + switch (keypress) { + case KEY_DOWN: case 'e': case 'j': case '\015': + 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 'g': case 'p': case '<': case '%': + buffer_up(num_flines + 1); + buffer_print(); + break; + case 'G': case '>': + buffer_down(num_flines + 1); + buffer_print(); + break; + case 'q': case 'Q': + tless_exit(0); + break; +#ifdef CONFIG_FEATURE_LESS_MARKS + 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': + if (inp_stdin) + save_input_to_file(); + break; + case 'E': + examine_file(); + break; +#ifdef CONFIG_FEATURE_LESS_FLAGS + case '=': + clear_line(); + m_status_print(); + break; +#endif +#ifdef CONFIG_FEATURE_LESS_REGEXP + case '/': + regex_process(); + buffer_print(); + break; + case 'n': + goto_match(match_pos + 1); + buffer_print(); + break; + case 'N': + goto_match(match_pos - 1); + buffer_print(); + break; + case '?': + search_backwards(); + buffer_print(); + break; +#endif +#ifdef CONFIG_FEATURE_LESS_FLAGCS + case '-': + flag_change(); + buffer_print(); + break; + case '_': + show_flag_status(); + break; +#endif +#ifdef CONFIG_FEATURE_LESS_BRACKETS + case '{': case '(': case '[': + match_right_bracket(keypress); + break; + case '}': case ')': case ']': + match_left_bracket(keypress); + break; +#endif + case ':': + colon_process(); + break; + default: + break; + } + if (isdigit(keypress)) + number_process(keypress); +} + +static void colon_process() { + + int keypress; + + /* Clear the current line and print a prompt */ + clear_line(); + printf(" :"); + + keypress = tless_getch(); + switch (keypress) { + case 'd': + remove_current_file(); + break; + case 'e': + examine_file(); + break; +#ifdef CONFIG_FEATURE_LESS_FLAGS + case 'f': + clear_line(); + m_status_print(); + break; +#endif + case 'n': + next_file(); + break; + case 'p': + previous_file(); + break; + case 'q': + tless_exit(0); + break; + case 'x': + first_file(); + break; + default: + break; + } +} + +static void number_process(int first_digit) { + + int i = 1; + int num; + char num_input[80]; + char keypress; + 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 */ + while((num_input[i] = tless_getch()) && isdigit(num_input[i])) { + printf("%c",num_input[i]); + i++; + } + + /* Take the final letter out of the digits string */ + keypress = num_input[i]; + num_input[i] = '\0'; + i--; + num = atoi(num_input); + + /* 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); + buffer_print(); + break; + case KEY_UP: case 'b': case 'w': case 'y': case 'u': + buffer_up(num); + buffer_print(); + break; + case 'g': case '<': case 'G': case '>': + if (num_flines >= height - 2) + buffer_line(num - 1); + buffer_print(); + break; + case 'p': case '%': + buffer_line(reverse_percent(num)); + buffer_print(); + break; +#ifdef CONFIG_FEATURE_LESS_REGEXP + case 'n': + goto_match(match_pos + num - 1); + buffer_print(); + break; + case '/': + regex_process(); + goto_match(num - 1); + buffer_print(); + break; + case '?': + num_back_match = num; + search_backwards(); + buffer_print(); + break; +#endif + default: + break; + } +} + +#ifdef CONFIG_FEATURE_LESS_FLAGCS +static void flag_change() { + + int keypress; + + clear_line(); + printf("-"); + keypress = tless_getch(); + + switch (keypress) { + case 'M': + M_FLAG = !M_FLAG; + break; + case 'm': + m_FLAG = !m_FLAG; + break; + case 'E': + E_FLAG = !E_FLAG; + break; + case '~': + TILDE_FLAG = !TILDE_FLAG; + break; + default: + break; + } +} + +static void show_flag_status() { + + int keypress; + int flag_val; + + clear_line(); + printf("_"); + keypress = tless_getch(); + + switch (keypress) { + case 'M': + flag_val = M_FLAG; + break; + case 'm': + flag_val = m_FLAG; + break; + case '~': + flag_val = TILDE_FLAG; + break; + case 'N': + flag_val = N_FLAG; + break; + case 'E': + flag_val = E_FLAG; + break; + default: + flag_val = 0; + break; + } + + clear_line(); + printf("%s%s%i%s", HIGHLIGHT, "The status of the flag is: ", flag_val, NORMAL); +} +#endif + +static void examine_file() { + + int newline_offset; + + clear_line(); + printf("Examine: "); + fgets(filename, 256, inp); + + /* As fgets adds a newline to the end of an input string, we + need to remove it */ + newline_offset = strlen(filename) - 1; + filename[newline_offset] = '\0'; + + files[num_files] = bb_xstrndup(filename, (strlen(filename) + 1) * sizeof(char)); + current_file = num_files + 1; + num_files++; + + inp_stdin = 0; + ea_inp_stdin = 1; + free_flines(); + data_readlines(); + buffer_init(); + buffer_print(); +} + +static void next_file() { + if (current_file != num_files) { + current_file++; + strcpy(filename, files[current_file - 1]); + free_flines(); + data_readlines(); + buffer_init(); + buffer_print(); + } + else { + clear_line(); + printf("%s%s%s", HIGHLIGHT, "No next file", NORMAL); + } +} + +static void previous_file() { + if (current_file != 1) { + current_file--; + strcpy(filename, files[current_file - 1]); + + free_flines(); + data_readlines(); + buffer_init(); + buffer_print(); + } + else { + clear_line(); + printf("%s%s%s", HIGHLIGHT, "No previous file", NORMAL); + } +} + +static void first_file() { + if (current_file != 1) { + current_file = 1; + strcpy(filename, files[current_file - 1]); + free_flines(); + data_readlines(); + buffer_init(); + buffer_print(); + } +} + +static void remove_current_file() { + + int i; + + if (current_file != 1) { + previous_file(); + for (i = 3; i <= num_files; i++) + files[i - 2] = files[i - 1]; + num_files--; + buffer_print(); + } + else { + next_file(); + for (i = 2; i <= num_files; i++) + files[i - 2] = files[i - 1]; + num_files--; + current_file--; + buffer_print(); + } +} + +static void full_repaint() { + + int temp_line_pos = line_pos; + data_readlines(); + buffer_init(); + buffer_line(temp_line_pos); + buffer_print(); +} + +/* This adds line numbers to every line, as the -N flag necessitates */ +static void add_linenumbers() { + + char current_line[256]; + int i; + + for (i = 0; i <= num_flines; i++) { + safe_strncpy(current_line, flines[i], 256); + flines[i] = xrealloc(flines[i], strlen(current_line) + 7 ); + sprintf(flines[i],"%5d %s", i+1, current_line); + } +} + +static void save_input_to_file() { + + char current_line[256]; + int i; + FILE *fp; + + clear_line(); + printf("Log file: "); + fgets(current_line, 256, inp); + current_line[strlen(current_line) - 1] = '\0'; + if (strlen(current_line)) { + fp = bb_xfopen(current_line, "w"); + for (i = 0; i < num_flines; i++) + fprintf(fp, "%s", flines[i]); + fclose(fp); + buffer_print(); + } + else + printf("%sNo log file%s", HIGHLIGHT, NORMAL); +} + +#ifdef CONFIG_FEATURE_LESS_MARKS +static void add_mark() { + + int letter; + int mark_line; + + clear_line(); + printf("Mark: "); + letter = tless_getch(); + + if (isalpha(letter)) { + mark_line = line_pos; + + /* 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; + num_marks++; + } + else { + clear_line(); + printf("%s%s%s", HIGHLIGHT, "Invalid mark letter", NORMAL); + } +} + +static void goto_mark() { + + int letter; + int i; + + clear_line(); + printf("Go to mark: "); + letter = tless_getch(); + 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])) { + clear_line(); + printf("%s%s%s", HIGHLIGHT, "Mark not set", NORMAL); + } + } + else { + clear_line(); + printf("%s%s%s", HIGHLIGHT, "Invalid mark letter", NORMAL); + } +} +#endif + +#ifdef CONFIG_FEATURE_LESS_REGEXP +/* The below two regular expression handler functions NEED development. */ + +/* Get a regular expression from the user, and then go through the current + file line by line, running a processing regex function on each one. */ +static void regex_process() { + + char uncomp_regex[100]; + char current_line[256]; + int i; + int j = 0; + regex_t *pattern; + + /* Reset variables */ + match_lines[0] = -1; + match_pos = 0; + num_matches = 0; + match_found = 0; + + pattern = (regex_t *) malloc(sizeof(regex_t)); + memset(pattern, 0, sizeof(regex_t)); + + /* Get the uncompiled regular expression from the user */ + clear_line(); + if (match_backwards) + printf("?"); + else + printf("/"); + scanf("%s", uncomp_regex); + + /* Compile the regex and check for errors */ + xregcomp(pattern, uncomp_regex, 0); + + /* Run the regex on each line of the current file here */ + for (i = 0; i <= num_flines; i++) { + strcpy(current_line, process_regex_on_line(flines[i], pattern)); + flines[i] = (char *) bb_xstrndup(current_line, sizeof(char) * (strlen(current_line)+1)); + + if (match_found) { + match_lines[j] = i; + j++; + } + } + + num_matches = j; + + if ((match_lines[0] != -1) && (num_flines > height - 2)) + buffer_line(match_lines[0]); + else + buffer_init(); +} + +char *process_regex_on_line(char *line, regex_t *pattern) { + /* This function takes the regex and applies it to the line. + Each part of the line that matches has the HIGHLIGHT + and NORMAL escape sequences placed around it by + insert_highlights, and then the line is returned. */ + + int match_status; + char *line2 = (char *) malloc((sizeof(char) * (strlen(line) + 1)) + 64); + char sub_line[256]; + int prev_eo = 0; + memset(sub_line, 0, 256); + strcpy(line2, line); + regmatch_t match_structs; + + match_found = 0; + match_status = regexec(pattern, line2, 1, &match_structs, 0); + + while (match_status == 0) { + + memset(sub_line, 0, 256); + + if (match_found == 0) + match_found = 1; + + line2 = insert_highlights(line2, match_structs.rm_so + prev_eo, match_structs.rm_eo + prev_eo); + if (match_structs.rm_eo + 11 + prev_eo < strlen(line2)) + strcat(sub_line, line2 + match_structs.rm_eo + 11 + prev_eo); + + prev_eo += match_structs.rm_eo + 11; + match_status = regexec(pattern, sub_line, 1, &match_structs, REG_NOTBOL); + } + + return line2; +} + +char *insert_highlights (char *line, int start, int end) { + + char *new_line = (char *) malloc((sizeof(char) * (strlen(line) + 1)) + 10); + memset(new_line, 0, ((sizeof(char) * (strlen(line) + 1)) + 10)); + strncat(new_line, line, start); + strcat(new_line, HIGHLIGHT); + strncat(new_line, line + start, end - start); + strcat(new_line, NORMAL); + strncat(new_line, line + end, strlen(line) - end); + + return new_line; +} + +static void goto_match(int match) { + + /* This goes to a specific match - all line positions of matches are + stored within the match_lines[] array. */ + if ((match < num_matches) && (match >= 0)) { + buffer_line(match_lines[match]); + match_pos = match; + } +} + +static void search_backwards() { + + int current_linepos = line_pos; + int i; + + match_backwards = 1; + regex_process(); + + for (i = 0; i < num_matches; i++) { + if (match_lines[i] > current_linepos) { + buffer_line(match_lines[i - num_back_match]); + break; + } + } + + /* Reset variables */ + match_backwards = 0; + num_back_match = 1; + +} +#endif + +#ifdef CONFIG_FEATURE_LESS_BRACKETS + +static char opp_bracket (char bracket) { + + switch (bracket) { + case '{': case '[': + return bracket + 2; + break; + case '(': + return ')'; + break; + case '}': case ']': + return bracket - 2; + break; + case ')': + return '('; + break; + default: + return 0; + break; + } +} + +static void match_right_bracket(char bracket) { + + int bracket_line = -1; + int i; + + if (strchr(flines[line_pos], bracket) == NULL) { + clear_line(); + printf("%s%s%s", HIGHLIGHT, "No bracket in top line", NORMAL); + } + else { + for (i = line_pos + 1; i < num_flines; i++) { + if (strchr(flines[i], opp_bracket(bracket)) != NULL) { + bracket_line = i; + break; + } + } + + if (bracket_line == -1) { + clear_line(); + printf("%s%s%s", HIGHLIGHT, "No matching bracket found", NORMAL); + } + + buffer_line(bracket_line - height + 2); + buffer_print(); + } +} + +static void match_left_bracket (char bracket) { + + int bracket_line = -1; + int i; + + if (strchr(flines[line_pos + height - 2], bracket) == NULL) { + clear_line(); + printf("%s%s%s", HIGHLIGHT, "No bracket in bottom line", NORMAL); + printf("%s", flines[line_pos + height]); + sleep(4); + } + else { + for (i = line_pos + height - 2; i >= 0; i--) { + if (strchr(flines[i], opp_bracket(bracket)) != NULL) { + bracket_line = i; + break; + } + } + + if (bracket_line == -1) { + clear_line(); + printf("%s%s%s", HIGHLIGHT, "No matching bracket found", NORMAL); + } + + buffer_line(bracket_line); + buffer_print(); + } +} + +#endif + +int less_main(int argc, char **argv) { + + unsigned long flags; + int keypress; + + flags = bb_getopt_ulflags(argc, argv, "EMNm~"); + E_FLAG = (flags & 1); + M_FLAG = (flags & 2); + N_FLAG = (flags & 4); + m_FLAG = (flags & 8); + TILDE_FLAG = (flags & 16); + + argc -= optind; + argv += optind; + files = argv; + num_files = argc; + + if (!num_files) { + if (ttyname(STDIN_FILENO) == NULL) + inp_stdin = 1; + else { + bb_error_msg("Missing filename"); + bb_show_usage(); + } + } + + strcpy(filename, (inp_stdin) ? "stdin" : files[0]); + tty_width_height(); + data_readlines(); + buffer_init(); + buffer_print(); + + while (1) { + keypress = tless_getch(); + keypress_process(keypress); + } +} |