Author: Adam Slattery slattery at students.missouri.edu
Subject: [BusyBox] rpm2cpio bzip2 decompression (patch included)
URL: http://www.busybox.net/lists/busybox/2004-May/011669.html
CVS: http://www.busybox.net/cgi-bin/viewcvs.cgi/trunk/busybox/patches/rpm2cpio_bzip2.patch?rev=9001

Index: busybox-1.2.2/archival/Config.in
===================================================================
--- busybox-1.2.2.orig/archival/Config.in
+++ busybox-1.2.2/archival/Config.in
@@ -127,6 +127,14 @@ config CONFIG_RPM2CPIO
 	help
 	  Converts an RPM file into a CPIO archive.
 
+config CONFIG_FEATURE_RPM2CPIO_BZIP2
+	bool "  Support bzip2 decompression"
+	default n
+	depends on CONFIG_RPM2CPIO
+	help
+	  If you enable this option you'll be able to extract
+	  rpms compressed with bzip2.
+
 config CONFIG_RPM
 	bool "rpm"
 	default n
Index: busybox-1.2.2/archival/libunarchive/Makefile.in
===================================================================
--- busybox-1.2.2.orig/archival/libunarchive/Makefile.in
+++ busybox-1.2.2/archival/libunarchive/Makefile.in
@@ -59,6 +59,7 @@ LIBUNARCHIVE-$(CONFIG_FEATURE_DEB_TAR_LZ
 LIBUNARCHIVE-$(CONFIG_GUNZIP) += $(GUNZIP_FILES)
 LIBUNARCHIVE-$(CONFIG_FEATURE_GUNZIP_UNCOMPRESS) += decompress_uncompress.o
 LIBUNARCHIVE-$(CONFIG_RPM2CPIO) += $(GUNZIP_FILES) get_header_cpio.o
+LIBUNARCHIVE-$(CONFIG_FEATURE_RPM2CPIO_BZIP2) += decompress_bunzip2.o
 LIBUNARCHIVE-$(CONFIG_RPM) += $(GUNZIP_FILES) get_header_cpio.o
 LIBUNARCHIVE-$(CONFIG_TAR) += get_header_tar.o
 LIBUNARCHIVE-$(CONFIG_FEATURE_TAR_BZIP2) += decompress_bunzip2.o get_header_tar_bz2.o
Index: busybox-1.2.2/archival/rpm2cpio.c
===================================================================
--- busybox-1.2.2.orig/archival/rpm2cpio.c
+++ busybox-1.2.2/archival/rpm2cpio.c
@@ -91,15 +91,27 @@ int rpm2cpio_main(int argc, char **argv)
 	skip_header(rpm_fd);
 
 	bb_xread_all(rpm_fd, &magic, 2);
-	if ((magic[0] != 0x1f) || (magic[1] != 0x8b)) {
-		bb_error_msg_and_die("Invalid gzip magic");
+	if ((magic[0] == 0x1f) || (magic[1] == 0x8b)) {
+		check_header_gzip(rpm_fd);
+		if (inflate_gunzip(rpm_fd, fileno(stdout)) != 0)
+			bb_error_msg("Error inflating (gzip)");
 	}
 
-	check_header_gzip(rpm_fd);
-	if (inflate_gunzip(rpm_fd, STDOUT_FILENO) != 0) {
-		bb_error_msg("Error inflating");
+	if ((magic[0] == 'B') && (magic[1] == 'Z')) {
+#ifdef CONFIG_FEATURE_RPM2CPIO_BZIP2
+		/* return to position before magic (eek..!) */
+		lseek(rpm_fd, -2, SEEK_CUR);
+		if(uncompressStream(rpm_fd, fileno(stdout)) != 0)
+			bb_error_msg("Error inflating (bzip2)");
+#else
+		bb_error_msg_and_die("bzip2 not supported");
+#endif
 	}
 
+	else
+		bb_error_msg_and_die("not gzip or bzip2 compressed");
+  
+
 	close(rpm_fd);
 
 	return 0;