Patch from Denis Vlasenko: unlzma was make files with mode 777.  Tweak
everything to do stat() and use xopen3().
diff --git a/archival/bunzip2.c b/archival/bunzip2.c
index 1b074c4..09364b4 100644
--- a/archival/bunzip2.c
+++ b/archival/bunzip2.c
@@ -41,16 +41,21 @@
 
 	/* Check that the input is sane.  */
 	if (isatty(src_fd) && (opt & BUNZIP2_OPT_FORCE) == 0) {
-		bb_error_msg_and_die("compressed data not read from terminal.  Use -f to force it.");
+		bb_error_msg_and_die("Compressed data not read from terminal.  Use -f to force it.");
 	}
 
 	if (filename) {
+		struct stat stat_buf;
 		char *extension=filename+strlen(filename)-4;
 		if (strcmp(extension, ".bz2") != 0) {
 			bb_error_msg_and_die("Invalid extension");
 		}
+		/* TODO: xstat */
+		if (stat(filename, &stat_buf) < 0) {
+			bb_error_msg_and_die("Couldn't stat file %s", filename);
+		}
 		*extension=0;
-		dst_fd = bb_xopen(filename, O_WRONLY | O_CREAT);
+		dst_fd = bb_xopen3(filename, O_WRONLY | O_CREAT, stat_buf.st_mode);
 	} else dst_fd = STDOUT_FILENO;
 	status = uncompressStream(src_fd, dst_fd);
 	if(filename) {
diff --git a/archival/gunzip.c b/archival/gunzip.c
index 7b93929..35449b0 100644
--- a/archival/gunzip.c
+++ b/archival/gunzip.c
@@ -137,11 +137,8 @@
 				bb_error_msg_and_die("Invalid extension");
 			}
 
-			/* Open output file */
-			dst_fd = bb_xopen(new_path, O_WRONLY | O_CREAT);
-
-			/* Set permissions on the file */
-			chmod(new_path, stat_buf.st_mode);
+			/* Open output file (with correct permissions) */
+			dst_fd = bb_xopen3(new_path, O_WRONLY | O_CREAT, stat_buf.st_mode);
 
 			/* If unzip succeeds remove the old file */
 			delete_path = old_path;
diff --git a/archival/unlzma.c b/archival/unlzma.c
index dc85cb2..404da0a 100644
--- a/archival/unlzma.c
+++ b/archival/unlzma.c
@@ -41,13 +41,18 @@
 		filename = 0;
 
 	if (filename) {
+		struct stat stat_buf;
 		char *extension = filename + strlen(filename) - 5;
 
 		if (strcmp(extension, ".lzma") != 0) {
 			bb_error_msg_and_die("Invalid extension");
 		}
+		/* TODO: xstat? */
+		if (stat(filename, &stat_buf) < 0) {
+			bb_error_msg_and_die("Couldn't stat file %s", filename);
+		}
 		*extension = 0;
-		dst_fd = bb_xopen(filename, O_WRONLY | O_CREAT);
+		dst_fd = bb_xopen3(filename, O_WRONLY | O_CREAT, stat_buf.st_mode);
 	} else
 		dst_fd = STDOUT_FILENO;
 	status = unlzma(src_fd, dst_fd);