From: Tim Kientzle <kientzle@gmail.com>
Date: Sun, 16 May 2010 20:33:30 +0000 (-0400)
Subject: Properly support filter(-1) as a shorthand for "the last filter",
X-Git-Tag: v3.0.0a~1001
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=4a154d88f95b647e64d3c197eb5d88b914d9bec0;p=thirdparty%2Flibarchive.git

Properly support filter(-1) as a shorthand for "the last filter",
which is always the client proxy.  In particular, tar uses this for
reporting position in the input stream.

SVN-Revision: 2403
---

diff --git a/libarchive/archive_read.c b/libarchive/archive_read.c
index 59a4c490a..9cdc23f17 100644
--- a/libarchive/archive_read.c
+++ b/libarchive/archive_read.c
@@ -864,7 +864,16 @@ get_filter(struct archive *_a, int n)
 {
 	struct archive_read *a = (struct archive_read *)_a;
 	struct archive_read_filter *f = a->filter;
-	/* XXX handle n == -1 */
+	/* We use n == -1 for 'the last filter', which is always the client proxy. */
+	if (n == -1 && f != NULL) {
+		struct archive_read_filter *last = f;
+		f = f->upstream;
+		while (f != NULL) {
+			last = f;
+			f = f->upstream;
+		}
+		return (last);
+	}
 	if (n < 0)
 		return NULL;
 	while (n > 0 && f != NULL) {
@@ -1095,6 +1104,7 @@ __archive_read_filter_ahead(struct archive_read_filter *filter,
 			bytes_read = (filter->read)(filter,
 			    &filter->client_buff);
 			if (bytes_read < 0) {		/* Read error. */
+fprintf(stderr, "Filter read ahead saw bytes_read=%d\n", bytes_read);
 				filter->client_total = filter->client_avail = 0;
 				filter->client_next = filter->client_buff = NULL;
 				filter->fatal = 1;
@@ -1272,6 +1282,7 @@ advance_file_pointer(struct archive_read_filter *filter, int64_t request)
 		bytes_read = (filter->read)(filter, &filter->client_buff);
 
 		if (bytes_read < 0) {
+			fprintf(stderr, "Filter skip saw bytes_read=%d\n", bytes_read);
 			filter->client_buff = NULL;
 			filter->fatal = 1;
 			return (bytes_read);