[leafnode-list] SIGCHLD, read EOF, and checking EINTR

[Jeffrey Goldberg <jeffrey@xxxxxxxxxxxx>]

Below is a patch to getline.c for 2.08b_ma10pre2  (though getline.c hasn't
changed in a while so the patch will apply to older versions).

The purpose of the patch is to fix a long standing bug of a
fetchnews run causing leafnode to incorrectly think that a connected
client has gone away.  That is, there is a getc loop in getline that
treats an EOF as the client haven gone away.  However, an EOF can also
occur if there was a signal (say a SIGCHLD) at which point the EOF will be
accompanied by an errno of EINT. (see read(2)).

So this patch (originally contributed by a pine developer, but slightly
modified by me to keep up with recent versions of getline.c) simply wraps
that loop in a test of errno == EINTR, so as not to consider the client
dead on an EOF after an signal.

I would really appreciate it if this patch made it into Mattias's
development thread so I (and others) wouldn't have to re-apply it for each
new verions.

PS:  I really appreciate the most recent change in debugging output.  That
makes my cron jobs run more smoothly.

Cheers,

-j

-- 
Jeffrey Goldberg                            http://www.goldmark.org/jeff/
Relativism is the triumph of authority over truth, convention over justice


--- getline.c-orig	Mon Feb  4 22:09:32 2002
+++ getline.c	Mon Feb  4 22:13:05 2002
@@ -22,6 +22,8 @@
 #ifdef WITH_DMALLOC
 #include <dmalloc.h>
 #endif
+#include "errno.h"
+extern int errno;

 ssize_t
 _getline( /*@out@*/ char *to, size_t size, FILE * stream)
@@ -32,13 +34,19 @@
     if (1 > size)
 	return -1;
     size--;
-    while (size > 0 && ((c = getc(stream)) != EOF)) {
-	*to = (unsigned char)c;
-	to++;
-	i++;
-	if (c == (int)'\n')
-	    break;
-	size--;
+    for(errno = 0; size > 0 && !errno; ) {
+	if((c = getc(stream)) != EOF) {
+	    *to=(unsigned char)c;
+	    to++;
+	    i++;
+	    if(c == (int)'\n')
+		break;
+	    size --;
+	}
+	else if(errno == EINTR) {
+	    clearerr(stream);
+	    errno = 0;
+	}
     }
     *to = '\0';
     if (ferror(stream))


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