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-rw-r--r--core/vi.c269
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diff --git a/core/vi.c b/core/vi.c
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+/* vi/ex - visual/text editor
+ * Copyright (C) 2022 Ferass EL HAFIDI
+ *
+ * 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 3 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, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <signal.h>
+#include <string.h>
+#include <time.h>
+#include <termios.h>
+#include <sys/ioctl.h>
+#include <libgen.h>
+#include "version.h"
+
+#ifndef COMPILETIME
+#define COMPILETIME
+#endif
+
+/*** ANSI VT100 escape codes ***/
+/* Colors */
+#define ANSI_WHITEBG "\33[38;5;0;48;5;255m"
+#define ANSI_RESET "\33[m"
+/* Other escape codes */
+#define ANSI_CLEARLINE "\33[2K\r"
+#define ANSI_CLEARALL "\e[1;1H\e[2J"
+
+/********** Common - used by both vi and ex **********/
+int print_string(char *string);
+
+int print_string(char *string) {
+ return write(STDOUT_FILENO, string, strlen(string));
+}
+
+/********************** ex mode **********************/
+int _ex_main(int argc, char *argv[]);
+
+int _ex_main(int argc, char *argv[]) {
+ print_string("<Not implemented>\n");
+ return 0; /* Not implemented yet. */
+}
+
+/********************** vi mode **********************/
+struct cursor_pos {
+ /* Neat way to keep track of the cursor's position. */
+ unsigned int x;
+ unsigned int y;
+};
+
+int _vi_main(int argc, char *argv[]);
+int _vi_set_cursor_pos(unsigned int x, unsigned int y);
+int _vi_init(unsigned int lines, unsigned int columns,
+ char buffer[4096], struct cursor_pos cposition, long int offset_position,
+ FILE *filstr);
+long int _vi_go_up(unsigned int lines, unsigned int columns,
+ char buffer[4096], FILE *filstr, long int offset_position);
+long int _vi_go_down(unsigned int lines, unsigned int columns,
+ char buffer[4096], FILE *filstr, long int offset_position);
+void _vi_printUsage();
+
+int _vi_main(int argc, char *argv[]) {
+ int argument, offset;
+ char cmd;
+ FILE *filstr;
+ char buffer[4096];
+ struct sigaction signal_action;
+ struct termios oldattr, newattr;
+ struct winsize w;
+ struct cursor_pos cposition;
+ ioctl(STDOUT_FILENO, TIOCGWINSZ, &w);
+ unsigned int lines = w.ws_row - 1;
+ unsigned int columns = w.ws_col - 1;
+
+ while ((argument = getopt(argc, argv, "")) != -1) {
+ if (argument == '?') {
+ _vi_printUsage();
+ return 1;
+ }
+ }
+ argc -= optind;
+ argv += optind;
+
+ signal_action.sa_handler = SIG_IGN;
+ sigemptyset(&signal_action.sa_mask);
+ sigaction(SIGINT, &signal_action, NULL);
+ setvbuf(stdout, NULL, _IONBF, 0);
+ /* Initialise vi */
+ if (argv[0]) {
+ filstr = fopen(argv[0], "r+");
+ if (errno) {
+ if (errno != ENOENT)
+ return errno;
+ }
+ } _vi_init(lines, columns, buffer, cposition, offset, filstr);
+ for (;;) {
+ /* Get a character */
+ tcgetattr(0, &oldattr); /* Get previous terminal parameters */
+ newattr = oldattr;
+ newattr.c_lflag &= ~( ICANON | ECHO ); /* Disable ECHO and ICANON */
+ tcsetattr(0, TCSANOW, &newattr); /* Set net parameters */
+ cmd = getchar();
+ switch (cmd) {
+ /*********************** Moving the cursor ***********************/
+ case 'k': /* up */
+ if (cposition.y != 1)
+ _vi_set_cursor_pos(cposition.x, (cposition.y = cposition.y - 1));
+ else {
+ _vi_set_cursor_pos(1, 1);
+ offset = _vi_go_up(lines, columns, buffer, filstr, offset);
+ _vi_set_cursor_pos(cposition.x, cposition.y);
+ }
+ break;
+ case 'j': /* down */
+ if (cposition.y != lines - 1)
+ _vi_set_cursor_pos(cposition.x, (cposition.y = cposition.y + 1));
+ else if (!feof(filstr)) {
+ _vi_set_cursor_pos(1, 1);
+ offset = _vi_go_down(lines, columns, buffer, filstr, offset);
+ _vi_set_cursor_pos(cposition.x, cposition.y);
+ }
+ break;
+ case 'l': /* right */
+ if (cposition.x != columns)
+ _vi_set_cursor_pos((cposition.x = cposition.x + 1), cposition.y);
+ break;
+ case 'h': /* left */
+ if (cposition.x != 0)
+ _vi_set_cursor_pos((cposition.x = cposition.x - 1), cposition.y);
+ break;
+ /************************* Command mode: *************************/
+ case ':':
+ _vi_set_cursor_pos(1, lines);
+ print_string(ANSI_CLEARLINE ":");
+ tcsetattr(0, TCSANOW, &oldattr); /* Restore old parameters */
+ cmd = getchar();
+ switch (cmd) {
+ case '\33':
+ _vi_set_cursor_pos(1, lines);
+ print_string(ANSI_CLEARLINE);
+ break;
+ case 'q':
+ print_string(ANSI_CLEARALL); /* Clear screen */
+ _vi_set_cursor_pos(1, 1); /* Reset the cursor position */
+ if (filstr) fclose(filstr);
+ return 0;
+ case '\n':
+ break;
+ default:
+ _vi_set_cursor_pos(1, lines);
+ print_string("unknown command");
+ break;
+ }
+ _vi_set_cursor_pos(cposition.x, cposition.y);
+ }
+ tcsetattr(0, TCSANOW, &oldattr); /* Restore old parameters */
+ }
+ return 0;
+}
+
+int _vi_init(unsigned int lines, unsigned int columns,
+ char buffer[4096], struct cursor_pos cposition,
+ long int offset_position, FILE *filstr) {
+ int status = 0;
+ print_string(ANSI_CLEARALL); /* Clear screen */
+ _vi_set_cursor_pos(1, 0);
+ if (filstr) {
+ if (fgets(buffer, 4096, filstr) != NULL) {
+ offset_position = ftell(filstr);
+ fputs(buffer, stdout);
+ }
+ for (unsigned int i = 1; i < (lines - 1); i++) {
+ if (fgets(buffer, 4096, filstr) != NULL) {
+ fputs(buffer, stdout);
+ }
+ else {
+ fputs("~\n", stdout);
+ status = 1; /* EOF */
+ }
+ }
+ } else {
+ for (unsigned int i = 1; i < (lines ); i++)
+ fputs("~\n", stdout);
+ status = 2; /* No file */
+ } _vi_set_cursor_pos((cposition.x = 1), (cposition.y = 1));
+ return status;
+}
+
+long int _vi_go_up(unsigned int lines, unsigned int columns,
+ char buffer[4096], FILE *filstr, long int offset_position) {
+ /* Really hacky stuff. TODO: Rewrite. */
+ int status = 0, offset_one_line_before;
+ print_string(ANSI_CLEARALL); /* Clear screen */
+ rewind(filstr);
+ if (ftell(filstr) == offset_position) return offset_position;
+ for (; fgets(buffer, 4096, filstr) != NULL &&
+ (ftell(filstr) != offset_position &&
+ (offset_one_line_before = ftell(filstr)));)
+ /* Do nothing. */ ;
+ for (unsigned int i = 0; i < (lines - 1); i++) {
+ if (fgets(buffer, 4096, filstr) != NULL) {
+ fputs(buffer, stdout);
+ }
+ else {
+ fputs("~\n", stdout);
+ status = 1; /* EOF */
+ }
+ } /* Hacky hack */
+ _vi_set_cursor_pos(1, lines);
+ print_string(ANSI_CLEARLINE);
+ return offset_one_line_before;
+}
+
+long int _vi_go_down(unsigned int lines, unsigned int columns,
+ char buffer[4096], FILE *filstr, long int offset_position) {
+ int status = 0;
+ print_string(ANSI_CLEARALL); /* Clear screen */
+ fseek(filstr, offset_position, SEEK_SET);
+ if (fgets(buffer, 4096, filstr) != NULL)
+ offset_position = ftell(filstr);
+
+ for (unsigned int i = 0; i < (lines); i++) {
+ if (fgets(buffer, 4096, filstr) != NULL) {
+ fputs(buffer, stdout);
+ }
+ else {
+ fputs("~\n", stdout);
+ status = 1; /* EOF */
+ }
+ }
+ //fposition.start = ftell(filstr);
+ //fposition_start_backup = ftell(filstr);
+ //if (fgets(buffer, 4096, filstr) != NULL)
+ // fposition.end = ftell(filstr);
+ /* Hacky hack */
+ _vi_set_cursor_pos(1, lines);
+ print_string(ANSI_CLEARLINE);
+ return offset_position;
+}
+
+int _vi_set_cursor_pos(unsigned int x, unsigned int y) {
+ return printf("\033[%u;%uH", (y), (x));
+}
+
+void _vi_printUsage() {
+ printf("Ferass' Base System. (%s)\n\n"
+ "Usage: vi [filename]\n\n"
+ "Visual editor.\n\n", COMPILETIME);
+}
+
+/************ main() ************/
+int main(int argc, char *argv[]) {
+ if (!strcmp(basename(argv[0]), "ex")) return _ex_main(argc, argv);
+ else /* Default to vi */ return _vi_main(argc, argv);
+ return 0; /* Never reached. */
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-10-17 23:57:17 +0000