pg.c

Util-linux 软件包包含许多工具。其中比较重要的是加载、卸载、格式化、分区和管理硬盘驱动器

			} else {
				p = endline(ttycols, b);
				sz = p - b;
				makeprint(b, sz);
				canjump = 1;
				write(1, b, sz);
				canjump = 0;
			}
		}
		if (dline >= pagelen || eof) {
			/*
			 * Time for prompting!
			 */
			if (eof && seekeof) {
				eof = seekeof = 0;
				if (line >= pagelen)
					line -= pagelen;
				else
					line = 0;
				dline = -1;
				continue;
			}
newcmd:
			if (eof) {
				if (fline == 0 || eflag)
					break;
				mesg(_("(EOF)"));
			}
			prompt((line - 1) / pagelen + 1);
			switch (cmd.key) {
			case '/':
				/*
				 * Search forward.
				 */
				search = FORWARD;
				oldline = line;
				searchcount = cmd.count;
				p = makepat();
				if (p != NULL && *p) {
					if (remembered == 1)
						regfree(&re);
					rerror = regcomp(&re, p,
						REG_NOSUB | REG_NEWLINE);
					if (rerror != 0) {
						mesg(_("RE error: "));
						sz = regerror(rerror, &re,
								b, READBUF);
						mesg(b);
						goto newcmd;
					}
					remembered = 1;
				} else if (remembered == 0) {
					mesg(_("No remembered search string"));
					goto newcmd;
				}
				continue;
			case '?':
			case '^':
				/*
				 * Search backward.
				 */
				search = BACKWARD;
				oldline = line;
				searchcount = cmd.count;
				p = makepat();
				if (p != NULL && *p) {
					if (remembered == 1)
						regfree(&re);
					rerror = regcomp(&re, p,
						REG_NOSUB | REG_NEWLINE);
					if (rerror != 0) {
						mesg("RE error: ");
						regerror(rerror, &re,
								b, READBUF);
						mesg(b);
						goto newcmd;
					}
					remembered = 1;
				} else if (remembered == 0) {
					mesg("No remembered search string");
					goto newcmd;
				}
				line -= pagelen;
				if (line <= 0)
					goto notfound_bw;
				while (line) {
					my_fseeko(find, --line * sizeof pos,
							SEEK_SET);
					if(fread(&pos, sizeof pos, 1,find)==0)
						tmperr(find, "index");
					my_fseeko(find, (off_t)0, SEEK_END);
					my_fseeko(fbuf, pos, SEEK_SET);
					if (fgets(b, READBUF, fbuf) == NULL)
						tmperr(fbuf, "buffer");
					colb(b);
					if (regexec(&re, b, 0, NULL, 0) == 0)
						searchcount--;
					if (searchcount == 0)
						goto found_bw;
				}
notfound_bw:
				line = oldline;
				search = searchcount = 0;
				mesg(_("Pattern not found"));
				goto newcmd;
found_bw:
				eof = search = dline = 0;
				skip(-1);
				switch (searchdisplay) {
				case TOP:
					/* line -= 1; */
					break;
				case MIDDLE:
					line -= pagelen / 2;
					break;
				case BOTTOM:
					if (line != 0)
						dline = -1;
					line -= pagelen;
					break;
				}
				if (line < 0)
					line = 0;
				continue;
			case 's':
				/*
				 * Save to file.
				 */
				p = cmd.cmdline;
				while (*++p == ' ');
				if (*p == '\0')
					goto newcmd;
				save = fopen(p, "wb");
				if (save == NULL) {
					cmd.count = errno;
					mesg(_("Cannot open "));
					mesg(p);
					mesg(": ");
					mesg(strerror(cmd.count));
					goto newcmd;
				}
				/*
				 * Advance to EOF.
				 */
				my_fseeko(find, (off_t)0, SEEK_END);
				for (;;) {
					if (!nobuf)
						my_fseeko(fbuf,(off_t)0,SEEK_END);
					pos = my_ftello(fbuf);
					if (fgets(b, READBUF, f) == NULL) {
						eofline = fline;
						break;
					}
					if (!nobuf)
						fputs(b, fbuf);
					fwrite(&pos, sizeof pos, 1, find);
					if (!fflag) {
						oldpos = pos;
						p = b;
						while (*(p = endline(ttycols,
									p))
								!= '\0') {
							pos = oldpos + (p - b);
							fwrite(&pos,
								sizeof pos,
								1, find);
							fline++;
							bline++;
						}
					}
					fline++;
					bline++;
				}
				my_fseeko(fbuf, (off_t)0, SEEK_SET);
				while ((sz = fread(b, sizeof *b, READBUF,
							fbuf)) != 0) {
					/*
					 * No error check for compat.
					 */
					fwrite(b, sizeof *b, sz, save);
				}
				fclose(save);
				my_fseeko(fbuf, (off_t)0, SEEK_END);
				mesg(_("saved"));
				goto newcmd;
			case 'l':
				/*
				 * Next line.
				 */
				if (*cmd.cmdline != 'l')
					eof = 0;
				if (cmd.count == 0)
					cmd.count = 1; /* compat */
				if (isdigit(cuc(*cmd.cmdline))) {
					line = cmd.count - 2;
					dline = 0;
				} else {
					if (cmd.count != 1) {
						line += cmd.count - 1
							- pagelen;
						dline = -1;
						skip(cmd.count);
					}
					/*
					 * Nothing to do if count==1.
					 */
				}
				break;
			case 'd':
				/*
				 * Half screen forward.
				 */
			case '\004':	/* ^D */
				if (*cmd.cmdline != cmd.key)
					eof = 0;
				if (cmd.count == 0)
					cmd.count = 1; /* compat */
				line += (cmd.count * pagelen / 2)
					- pagelen - 1;
				dline = -1;
				skip(cmd.count);
				break;
			case 'f':
				/*
				 * Skip forward.
				 */
				if (cmd.count <= 0)
					cmd.count = 1; /* compat */
				line += cmd.count * pagelen - 2;
				if (eof)
					line += 2;
				if (*cmd.cmdline != 'f')
					eof = 0;
				else if (eof)
					break;
				if (eofline && line >= eofline)
					line -= pagelen;
				dline = -1;
				skip(cmd.count);
				break;
			case '\0':
				/*
				 * Just a number, or '-', or <newline>.
				 */
				if (cmd.count == 0)
					cmd.count = 1; /* compat */
				if (isdigit(cuc(*cmd.cmdline)))
					line = (cmd.count - 1) * pagelen - 2;
				else
					line += (cmd.count - 1)
						* (pagelen - 1) - 2;
				if (*cmd.cmdline != '\0')
					eof = 0;
				if (cmd.count != 1) {
					skip(cmd.count);
					dline = -1;
				} else {
					dline = 1;
					line += 2;
				}
				break;
			case '$':
				/*
				 * Advance to EOF.
				 */
				if (!eof)
					skip(1);
				eof = 0;
				line = LONG_MAX;
				seekeof = 1;
				dline = -1;
				break;
			case '.':
			case '\014': /* ^L */
				/*
				 * Repaint screen.
				 */
				eof = 0;
				if (line >= pagelen)
					line -= pagelen;
				else
					line = 0;
				dline = 0;
				break;
			case '!':
				/*
				 * Shell escape.
				 */
				if (rflag) {
					mesg(progname);
					mesg(_(": !command not allowed in "
					       "rflag mode.\n"));
				} else {
					pid_t cpid;

					write(1, cmd.cmdline,
					      strlen(cmd.cmdline));
					write(1, "\n", 1);
					my_sigset(SIGINT, SIG_IGN);
					my_sigset(SIGQUIT, SIG_IGN);
					switch (cpid = fork()) {
					case 0:
						p = getenv("SHELL");
						if (p == NULL) p = "/bin/sh";
						if (!nobuf)
							fclose(fbuf);
						fclose(find);
						if (isatty(0) == 0) {
							close(0);
							open(tty, O_RDONLY);
						} else {
							fclose(f);
						}
						my_sigset(SIGINT, oldint);
						my_sigset(SIGQUIT, oldquit);
						my_sigset(SIGTERM, oldterm);
						execl(p, p, "-c",
							cmd.cmdline + 1, NULL);
						pgerror(errno, p);
						_exit(0177);
						/*NOTREACHED*/
					case -1:
						mesg(_("fork() failed, "
						       "try again later\n"));
						break;
					default:
						while (wait(NULL) != cpid);
					}
					my_sigset(SIGINT, sighandler);
					my_sigset(SIGQUIT, sighandler);
					mesg("!\n");
				}
				goto newcmd;
			case 'h':
				/*
				 * Help!
				 */
				write(1, copyright + 4, strlen(copyright + 4));
				write(1, helpscreen, strlen(helpscreen));
				goto newcmd;
			case 'n':
				/*
				 * Next file.
				 */
				if (cmd.count == 0)
					cmd.count = 1;
				nextfile = cmd.count;
				if (checkf()) {
					nextfile = 1;
					goto newcmd;
				}
				eof = 1;
				break;
			case 'p':
				/*
				 * Previous file.
				 */
				if (cmd.count == 0)
					cmd.count = 1;
				nextfile = 0 - cmd.count;
				if (checkf()) {
					nextfile = 1;
					goto newcmd;
				}
				eof = 1;
				break;
			case 'q':
			case 'Q':
				/*
				 * Exit pg.
				 */
				quit(exitstatus);
				/*NOTREACHED*/
			case 'w':
			case 'z':
				/*
				 * Set window size.
				 */
				if (cmd.count < 0)
					cmd.count = 0;
				if (*cmd.cmdline != cmd.key)
					pagelen = ++cmd.count;
				dline = 1;
				break;
			}
			if (line <= 0) {
				line = 0;
				dline = 0;
			}
			if (cflag && dline == 1) {
				dline = 0;
				line--;
			}
		}
		if (eof)
			break;
	}
	fclose(find);
	if (!nobuf)
		fclose(fbuf);
}

int
main(int argc, char **argv)
{
	int arg, i;
	char *p;
	FILE *input;

	progname = basename(argv[0]);

	setlocale(LC_MESSAGES, "");
	bindtextdomain(PACKAGE, LOCALEDIR);
	textdomain(PACKAGE);

	if (tcgetattr(1, &otio) == 0) {
		ontty = 1;
		oldint = my_sigset(SIGINT, sighandler);
		oldquit = my_sigset(SIGQUIT, sighandler);
		oldterm = my_sigset(SIGTERM, sighandler);
		setlocale(LC_CTYPE, "");
		setlocale(LC_COLLATE, "");
		tty = ttyname(1);
		setupterm(NULL, 1, &tinfostat);
		getwinsize();
		helpscreen = _(helpscreen);
	}
	for (arg = 1; argv[arg]; arg++) {
		if (*argv[arg] == '+')
			continue;
		if (*argv[arg] != '-' || argv[arg][1] == '\0')
			break;
		argc--;
		for (i = 1; argv[arg][i]; i++) {
			switch (argv[arg][i]) {
			case '-':
				if (i != 1 || argv[arg][i + 1])
					invopt(&argv[arg][i]);
				goto endargs;
			case '1': case '2': case '3': case '4': case '5':
			case '6': case '7': case '8': case '9': case '0':
				pagelen = atoi(argv[arg] + i);
				havepagelen = 1;
				goto nextarg;
			case 'c':
				cflag = 1;
				break;
			case 'e':
				eflag = 1;
				break;
			case 'f':
				fflag = 1;
				break;
			case 'n':
				nflag = 1;
				break;
			case 'p':
				if (argv[arg][i + 1]) {
					pstring = &argv[arg][i + 1];
				} else if (argv[++arg]) {
					--argc;
					pstring = argv[arg];
				} else
					needarg("-p");
				goto nextarg;
			case 'r':
				rflag = 1;
				break;
			case 's':
				sflag = 1;
				break;
			default:
				invopt(&argv[arg][i]);
			}
		}
nextarg:
		;
	}
endargs:
	for (arg = 1; argv[arg]; arg++) {
		if (*argv[arg] == '-') {
			if (argv[arg][1] == '-') {
				arg++;
				break;
			}
			if (argv[arg][1] == '\0')
				break;
			if (argv[arg][1] == 'p' && argv[arg][2] == '\0')
				arg++;
			continue;
		}
		if (*argv[arg] != '+')
			break;
		argc--;
		switch (*(argv[arg] + 1)) {
		case '\0':
			needarg("+");
			/*NOTREACHED*/
		case '1': case '2': case '3': case '4': case '5':
		case '6': case '7': case '8': case '9': case '0':
			startline = atoi(argv[arg] + 1);
			break;
		case '/':
			searchfor = argv[arg] + 2;
			if (*searchfor == '\0')
				needarg("+/");
			p = searchfor + strlen(searchfor) - 1;
			if (*p == '/') *p = '\0';
			if (*searchfor == '\0')
				needarg("+/");
			break;
		default:
			invopt(argv[arg]);
		}
	}
	if (argc == 1) {
		pgfile(stdin, "stdin");
	} else {
		files.first = arg;
		files.last = arg + argc - 1;
		for ( ; argv[arg]; arg += nextfile) {
			nextfile = 1;
			files.current = arg;
			if (argc > 2) {
				static int firsttime;
				firsttime++;
				if (firsttime > 1) {
					mesg(_("(Next file: "));
					mesg(argv[arg]);
					mesg(")");
newfile:
					if (ontty) {
					prompt(-1);
					switch(cmd.key) {
					case 'n':
						/*
					 	* Next file.
					 	*/
						if (cmd.count == 0)
							cmd.count = 1;
						nextfile = cmd.count;
						if (checkf()) {
							nextfile = 1;
							mesg(":");
							goto newfile;
						}
						continue;
					case 'p':
						/*
					 	* Previous file.
					 	*/
						if (cmd.count == 0)
							cmd.count = 1;
						nextfile = 0 - cmd.count;
						if (checkf()) {
							nextfile = 1;
							mesg(":");
							goto newfile;
						}
						continue;
					case 'q':
					case 'Q':
						quit(exitstatus);
				}
				} else mesg("\n");
				}
			}
			if (strcmp(argv[arg], "-") == 0)
				input = stdin;
			else {
				input = fopen(argv[arg], "r");
				if (input == NULL) {
					pgerror(errno, argv[arg]);
					exitstatus++;
					continue;
				}
			}
			if (ontty == 0 && argc > 2) {
				/*
				 * Use the prefix as specified by SUSv2.
				 */
				write(1, "::::::::::::::\n", 15);
				write(1, argv[arg], strlen(argv[arg]));
				write(1, "\n::::::::::::::\n", 16);
			}
			pgfile(input, argv[arg]);
			if (input != stdin)
				fclose(input);
		}
	}
	quit(exitstatus);
	/*NOTREACHED*/
	return 0;
}