From: Tim Kientzle <kientzle@gmail.com>
Date: Tue, 23 Feb 2010 16:18:00 +0000 (-0500)
Subject: Oops.  Forgot to initialize the is_disk_like variable.  While I'm
X-Git-Tag: v3.0.0a~1200
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=81b8193dacf21a071e8fdc919c3444f10ca7c490;p=thirdparty%2Flibarchive.git

Oops.  Forgot to initialize the is_disk_like variable.  While I'm
here, make the block size selection for disks be aware of the users
request.  Users should be able to ask for larger block sizes.

SVN-Revision: 1965
---

diff --git a/libarchive/archive_read_open_filename.c b/libarchive/archive_read_open_filename.c
index a726fed79..9cac80e62 100644
--- a/libarchive/archive_read_open_filename.c
+++ b/libarchive/archive_read_open_filename.c
@@ -94,7 +94,7 @@ archive_read_open_filename(struct archive *a, const char *filename,
 	struct read_file_data *mine;
 	void *buffer;
 	int fd;
-	int is_disk_like;
+	int is_disk_like = 0;
 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 	off_t mediasize = 0;
 #elif defined(__NetBSD__) || defined(__OpenBSD__)
@@ -139,8 +139,8 @@ archive_read_open_filename(struct archive *a, const char *filename,
 	 *  = "disk-like" devices support arbitrary lseek() and will
 	 *    support I/O requests of any size.  So we get easy skipping
 	 *    and can cheat on block sizes to get better performance.
-	 *  = "tape-like" devices require strict blocking and sometimes
-	 *    support specialized seek ioctls.
+	 *  = "tape-like" devices require strict blocking and use
+	 *    specialized ioctls for seeking.
 	 *  = "socket-like" devices cannot seek at all but can improve
 	 *    performance by using nonblocking I/O to read "whatever is
 	 *    available right now".
@@ -190,10 +190,15 @@ archive_read_open_filename(struct archive *a, const char *filename,
 
 	mine = (struct read_file_data *)calloc(1,
 	    sizeof(*mine) + strlen(filename));
-	/* For regular files and disks, ignore the block size passed
-	 * in and just use a fixed moderately large power of two. */
-	if (is_disk_like)
-		block_size = 64 * 1024;
+	/* Disk-like devices prefer power-of-two block sizes.  */
+	/* Use provided block_size as a guide so users have some control. */
+	if (is_disk_like) {
+		size_t new_block_size = 64 * 1024;
+		while (new_block_size < block_size
+		    && new_block_size < 64 * 1024 * 1024)
+			new_block_size *= 2;
+		block_size = new_block_size;
+	}
 	buffer = malloc(block_size);
 	if (mine == NULL || buffer == NULL) {
 		archive_set_error(a, ENOMEM, "No memory");