Date: Wed, 11 Jul 2007 13:10:04 GMT From: Niclas Zeising <niclas.zeising@gmail.com> To: freebsd-gnats-submit@FreeBSD.org Subject: bin/114498: [PATCH] bug in wall makes it skip characters Message-ID: <200707111310.l6BDA456079804@www.freebsd.org> Resent-Message-ID: <200707111320.l6BDK2ht063286@freefall.freebsd.org>
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>Number: 114498
>Category: bin
>Synopsis: [PATCH] bug in wall makes it skip characters
>Confidential: no
>Severity: non-critical
>Priority: low
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Wed Jul 11 13:20:02 GMT 2007
>Closed-Date:
>Last-Modified:
>Originator: Niclas Zeising
>Release: 7.0-CURRENT
>Organization:
N/A
>Environment:
N/A
>Description:
A bug in the makemsg() function in wall makes it skip one character when wrapping around the line to make a new one. It outputs character ... 78, 79, then cr-lf, then charcater 81, of what's inputed. The same goes for everytime it wraps a line, every 80th char is missing. This is rather annoying since missing characters can give words completely new meanings and wall is used when shutting down etc.
>How-To-Repeat:
just run wall with a message longer than 80 caracters without a newline and see as one char is missing in the output.
>Fix:
Attached patch revrites the loop in makemsg() a little so to not skip any characters that shouldn't be skipped. It also raises the warns level to 6 since wall seems to compile at warns 6, at least on i386... That part is not neccecary to include though.
Patch attached with submission follows:
diff -ur src/src/usr.bin/wall/Makefile src2/src/usr.bin/wall/Makefile
--- src/src/usr.bin/wall/Makefile Fri May 27 14:33:28 1994
+++ src2/src/usr.bin/wall/Makefile Tue Jul 10 17:20:55 2007
@@ -2,6 +2,7 @@
PROG= wall
SRCS= ttymsg.c wall.c
+WARNS= 6
BINGRP= tty
BINMODE=2555
diff -ur src/src/usr.bin/wall/wall.c src2/src/usr.bin/wall/wall.c
--- src/src/usr.bin/wall/wall.c Tue Feb 21 14:01:00 2006
+++ src2/src/usr.bin/wall/wall.c Wed Jul 11 14:56:14 2007
@@ -193,10 +193,10 @@
exit(1);
}
-void
+static void
makemsg(char *fname)
{
- int cnt;
+ int cnt = 0;
unsigned char ch;
struct tm *lt;
struct passwd *pw;
@@ -251,12 +251,15 @@
err(1, "can't read %s", fname);
setegid(egid);
}
- while (fgets(lbuf, sizeof(lbuf), stdin))
- for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) {
- if (ch == '\r') {
+ while (fgets(lbuf, sizeof(lbuf), stdin)) {
+ p = lbuf;
+ /* Thos loop is pending rewrite */
+ while ((ch = *p++) != '\0') {
+ /* for (cnt = 0, p = lbuf; (ch = *p) != '\0'; p++, cnt++) { */
+ if (ch == '\r')
cnt = 0;
- } else if (cnt == 79 || ch == '\n') {
- for (; cnt < 79; ++cnt)
+ else if (ch == '\n') {
+ for(; cnt < 79; cnt++)
putc(' ', fp);
putc('\r', fp);
putc('\n', fp);
@@ -269,13 +272,13 @@
if (ch & 0x80) {
ch &= 0x7F;
putc('M', fp);
- if (++cnt == 79) {
+ if (++cnt >= 79) {
putc('\r', fp);
putc('\n', fp);
cnt = 0;
}
putc('-', fp);
- if (++cnt == 79) {
+ if (++cnt >= 79) {
putc('\r', fp);
putc('\n', fp);
cnt = 0;
@@ -284,17 +287,28 @@
if (iscntrl(ch)) {
ch ^= 040;
putc('^', fp);
- if (++cnt == 79) {
+ if (++cnt >= 79) {
putc('\r', fp);
putc('\n', fp);
cnt = 0;
}
}
putc(ch, fp);
+ if (++cnt >= 79) {
+ putc('\r', fp);
+ putc('\n', fp);
+ cnt = 0;
+ }
} else {
putc(ch, fp);
+ if (++cnt >= 79) {
+ putc('\r', fp);
+ putc('\n', fp);
+ cnt = 0;
+ }
}
}
+ }
(void)fprintf(fp, "%79s\r\n", " ");
rewind(fp);
>Release-Note:
>Audit-Trail:
>Unformatted:
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