msgs.c

早期freebsd实现

				Lpp = NLINES;
			}
		}
	}
#endif
	Lpp -= 6;	/* for headers, etc. */

	already = NO;
	prevmsg = firstmsg;
	printing = YES;
	if (ruptible)
		signal(SIGINT, onintr);

	/*
	 * Main program loop
	 */
	for (msg = firstmsg; msg <= lastmsg; msg++) {

		sprintf(fname, "%s/%d", _PATH_MSGS, msg);
		newmsg = fopen(fname, "r");
		if (newmsg == NULL)
			continue;

		gfrsub(newmsg);		/* get From and Subject fields */
		if (locomode && !local) {
			fclose(newmsg);
			continue;
		}

		if (qopt) {	/* This has to be located here */
			printf("There are new messages.\n");
			exit(0);
		}

		if (already && !hdrs)
			putchar('\n');

		/*
		 * Print header
		 */
		if (totty)
			signal(SIGTSTP, onsusp);
		(void) setjmp(tstpbuf);
		already = YES;
		nlines = 2;
		if (seenfrom) {
			printf("Message %d:\nFrom %s %s", msg, from, date);
			nlines++;
		}
		if (seensubj) {
			printf("Subject: %s", subj);
			nlines++;
		}
		else {
			if (seenfrom) {
				putchar('\n');
				nlines++;
			}
			while (nlines < 6
			    && fgets(inbuf, sizeof inbuf, newmsg)
			    && inbuf[0] != '\n') {
				fputs(inbuf, stdout);
				nlines++;
			}
		}

		lct = linecnt(newmsg);
		if (lct)
			printf("(%d%slines) ", lct, seensubj? " " : " more ");

		if (hdrs) {
			printf("\n-----\n");
			fclose(newmsg);
			continue;
		}

		/*
		 * Ask user for command
		 */
		if (totty)
			ask(lct? MORE : (msg==lastmsg? NOMORE : NEXT));
		else
			inbuf[0] = 'y';
		if (totty)
			signal(SIGTSTP, SIG_DFL);
cmnd:
		in = inbuf;
		switch (*in) {
			case 'x':
			case 'X':
				exit(0);

			case 'q':
			case 'Q':
				quitit = YES;
				printf("--Postponed--\n");
				exit(0);
				/* intentional fall-thru */
			case 'n':
			case 'N':
				if (msg >= nextmsg) sep = "Flushed";
				prevmsg = msg;
				break;

			case 'p':
			case 'P':
				use_pager = (*in++ == 'p');
				/* intentional fallthru */
			case '\n':
			case 'y':
			default:
				if (*in == '-') {
					msg = prevmsg-1;
					sep = "replay";
					break;
				}
				if (isdigit(*in)) {
					msg = next(in);
					sep = in;
					break;
				}

				prmesg(nlines + lct + (seensubj? 1 : 0));
				prevmsg = msg;

		}

		printf("--%s--\n", sep);
		sep = "-";
		if (msg >= nextmsg) {
			nextmsg = msg + 1;
			fseek(msgsrc, 0L, 0);
			fprintf(msgsrc, "%d\n", nextmsg);
			fflush(msgsrc);
		}
		if (newmsg)
			fclose(newmsg);
		if (quitit)
			break;
	}

	/*
	 * Make sure .rc file gets updated
	 */
	if (--msg >= nextmsg) {
		nextmsg = msg + 1;
		fseek(msgsrc, 0L, 0);
		fprintf(msgsrc, "%d\n", nextmsg);
		fflush(msgsrc);
	}
	if (already && !quitit && lastcmd && totty) {
		/*
		 * save or reply to last message?
		 */
		msg = prevmsg;
		ask(NOMORE);
		if (inbuf[0] == '-' || isdigit(inbuf[0]))
			goto cmnd;
	}
	if (!(already || hush || qopt))
		printf("No new messages.\n");
	exit(0);
}

prmesg(length)
int length;
{
	FILE *outf;

	if (use_pager && length > Lpp) {
		signal(SIGPIPE, SIG_IGN);
		signal(SIGQUIT, SIG_IGN);
		sprintf(cmdbuf, _PATH_PAGER, Lpp);
		outf = popen(cmdbuf, "w");
		if (!outf)
			outf = stdout;
		else
			setbuf(outf, (char *)NULL);
	}
	else
		outf = stdout;

	if (seensubj)
		putc('\n', outf);

	while (fgets(inbuf, sizeof inbuf, newmsg)) {
		fputs(inbuf, outf);
		if (ferror(outf)) {
			clearerr(outf);
			break;
		}
	}

	if (outf != stdout) {
		pclose(outf);
		signal(SIGPIPE, SIG_DFL);
		signal(SIGQUIT, SIG_DFL);
	}
	else {
		fflush(stdout);
	}

	/* trick to force wait on output */
	stty(fileno(stdout), &otty);
}

void
onintr()
{
	signal(SIGINT, onintr);
	if (mailing)
		unlink(fname);
	if (sending) {
		unlink(fname);
		puts("--Killed--");
		exit(1);
	}
	if (printing) {
		putchar('\n');
		if (hdrs)
			exit(0);
		sep = "Interrupt";
		if (newmsg)
			fseek(newmsg, 0L, 2);
		intrpflg = YES;
	}
}

/*
 * We have just gotten a susp.  Suspend and prepare to resume.
 */
void
onsusp()
{

	signal(SIGTSTP, SIG_DFL);
	sigsetmask(0);
	kill(0, SIGTSTP);
	signal(SIGTSTP, onsusp);
	if (!mailing)
		longjmp(tstpbuf, 0);
}

linecnt(f)
FILE *f;
{
	off_t oldpos = ftell(f);
	int l = 0;
	char lbuf[BUFSIZ];

	while (fgets(lbuf, sizeof lbuf, f))
		l++;
	clearerr(f);
	fseek(f, oldpos, 0);
	return (l);
}

next(buf)
char *buf;
{
	int i;
	sscanf(buf, "%d", &i);
	sprintf(buf, "Goto %d", i);
	return(--i);
}

ask(prompt)
char *prompt;
{
	char	inch;
	int	n, cmsg;
	off_t	oldpos;
	FILE	*cpfrom, *cpto;

	printf("%s ", prompt);
	fflush(stdout);
	intrpflg = NO;
	(void) fgets(inbuf, sizeof inbuf, stdin);
	if ((n = strlen(inbuf)) > 0 && inbuf[n - 1] == '\n')
		inbuf[n - 1] = '\0';
	if (intrpflg)
		inbuf[0] = 'x';

	/*
	 * Handle 'mail' and 'save' here.
	 */
	if ((inch = inbuf[0]) == 's' || inch == 'm') {
		if (inbuf[1] == '-')
			cmsg = prevmsg;
		else if (isdigit(inbuf[1]))
			cmsg = atoi(&inbuf[1]);
		else
			cmsg = msg;
		sprintf(fname, "%s/%d", _PATH_MSGS, cmsg);

		oldpos = ftell(newmsg);

		cpfrom = fopen(fname, "r");
		if (!cpfrom) {
			printf("Message %d not found\n", cmsg);
			ask (prompt);
			return;
		}

		if (inch == 's') {
			in = nxtfld(inbuf);
			if (*in) {
				for (n=0; in[n] > ' '; n++) { /* sizeof fname? */
					fname[n] = in[n];
				}
				fname[n] = NULL;
			}
			else
				strcpy(fname, "Messages");
		}
		else {
			strcpy(fname, _PATH_TMP);
			mktemp(fname);
			sprintf(cmdbuf, _PATH_MAIL, fname);
			mailing = YES;
		}
		cpto = fopen(fname, "a");
		if (!cpto) {
			perror(fname);
			mailing = NO;
			fseek(newmsg, oldpos, 0);
			ask(prompt);
			return;
		}

		while (n = fread(inbuf, 1, sizeof inbuf, cpfrom))
			fwrite(inbuf, 1, n, cpto);

		fclose(cpfrom);
		fclose(cpto);
		fseek(newmsg, oldpos, 0);	/* reposition current message */
		if (inch == 's')
			printf("Message %d saved in \"%s\"\n", cmsg, fname);
		else {
			system(cmdbuf);
			unlink(fname);
			mailing = NO;
		}
		ask(prompt);
	}
}

gfrsub(infile)
FILE *infile;
{
	off_t frompos;

	seensubj = seenfrom = NO;
	local = YES;
	subj[0] = from[0] = date[0] = NULL;

	/*
	 * Is this a normal message?
	 */
	if (fgets(inbuf, sizeof inbuf, infile)) {
		if (strncmp(inbuf, "From", 4)==0) {
			/*
			 * expected form starts with From
			 */
			seenfrom = YES;
			frompos = ftell(infile);
			ptr = from;
			in = nxtfld(inbuf);
			if (*in) while (*in && *in > ' ') {
				if (*in == ':' || *in == '@' || *in == '!')
					local = NO;
				*ptr++ = *in++;
				/* what about sizeof from ? */
			}
			*ptr = NULL;
			if (*(in = nxtfld(in)))
				strncpy(date, in, sizeof date);
			else {
				date[0] = '\n';
				date[1] = NULL;
			}
		}
		else {
			/*
			 * not the expected form
			 */
			fseek(infile, 0L, 0);
			return;
		}
	}
	else
		/*
		 * empty file ?
		 */
		return;

	/*
	 * look for Subject line until EOF or a blank line
	 */
	while (fgets(inbuf, sizeof inbuf, infile)
	    && !(blankline = (inbuf[0] == '\n'))) {
		/*
		 * extract Subject line
		 */
		if (!seensubj && strncmp(inbuf, "Subj", 4)==0) {
			seensubj = YES;
			frompos = ftell(infile);
			strncpy(subj, nxtfld(inbuf), sizeof subj);
		}
	}
	if (!blankline)
		/*
		 * ran into EOF
		 */
		fseek(infile, frompos, 0);

	if (!seensubj)
		/*
		 * for possible use with Mail
		 */
		strncpy(subj, "(No Subject)\n", sizeof subj);
}

char *
nxtfld(s)
char *s;
{
	if (*s) while (*s && *s > ' ') s++;	/* skip over this field */
	if (*s) while (*s && *s <= ' ') s++;	/* find start of next field */
	return (s);
}