From dee0ce0cbdf56b773580eb7de0a1eb061bc56f7e Mon Sep 17 00:00:00 2001
From: Tim Kientzle <kientzle@FreeBSD.org>
Date: Tue, 29 Dec 2009 05:30:23 +0000
Subject: [PATCH] Catch decompression failures earlier.  In particular, this
 gives immediate feedback if we fail to fork an external decompression
 program.

---
 lib/libarchive/archive_read.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lib/libarchive/archive_read.c b/lib/libarchive/archive_read.c
index bef2438e1591..fd56dc607194 100644
--- a/lib/libarchive/archive_read.c
+++ b/lib/libarchive/archive_read.c
@@ -354,6 +354,7 @@ build_stream(struct archive_read *a)
 	int number_bidders, i, bid, best_bid;
 	struct archive_read_filter_bidder *bidder, *best_bidder;
 	struct archive_read_filter *filter;
+	ssize_t avail;
 	int r;
 
 	for (;;) {
@@ -392,6 +393,13 @@ build_stream(struct archive_read *a)
 			free(filter);
 			return (r);
 		}
+		/* Verify the filter by asking it for some data. */
+		__archive_read_filter_ahead(filter, 1, &avail);
+		if (avail < 0) {
+			/* If the read failed, bail out now. */
+			free(filter);
+			return (avail);
+		}
 		a->filter = filter;
 	}
 }