commit 771993d1fc6db95ae92ebe0200f7003554ea32da

Author: Panu Matilainen <pmatilai@redhat.com>

Date:   Mon Feb 21 08:47:52 2011 +0200

    Fix braindamage in the depgen helper collector loop (RhBug:675002)

    - Read any remaining data before exiting on SIGCHLD

    - Only perform one read() per loop, otherwise it could block

    - Handle EINTR while read()'ing

diff --git a/build/rpmfc.c b/build/rpmfc.c

index 56bcb12..29334e2 100644

--- a/build/rpmfc.c

+++ b/build/rpmfc.c

@@ -272,12 +272,6 @@ static StringBuf getOutputFrom(ARGV_t argv,

 	    break;

 	}

-	/* Child exited, we're done */

-	if (FD_ISSET(sigpipe, &ibits)) {

-	    while (read(sigpipe, buf, sizeof(buf)) > 0) {};

-	    break;

-	}

-

 	/* Write data to child */

 	if (writeBytesLeft > 0 && FD_ISSET(toProg[1], &obits)) {

 	    size_t nb = (1024 < writeBytesLeft) ? 1024 : writeBytesLeft;

@@ -293,11 +287,20 @@ static StringBuf getOutputFrom(ARGV_t argv,

 	/* Read when we get data back from the child */

 	if (FD_ISSET(fromProg[0], &ibits)) {

-	    int nbr;

-	    while ((nbr = read(fromProg[0], buf, sizeof(buf)-1)) > 0) {

-		buf[nbr] = '\0';

-		appendStringBuf(readBuff, buf);

+	    int nbr = read(fromProg[0], buf, sizeof(buf)-1);

+	    if (nbr < 0 && errno == EINTR) continue;

+	    if (nbr < 0) {

+		myerrno = errno;

+		break;

 	    }

+	    buf[nbr] = '\0';

+	    appendStringBuf(readBuff, buf);

+	}

+

+	/* Child exited, we're done */

+	if (FD_ISSET(sigpipe, &ibits)) {

+	    while (read(sigpipe, buf, sizeof(buf)) > 0) {};

+	    break;

 	}

     }