daemon: Add zstd support to guestfs_file_architecture

This is required so we can determine the file architecture of
zstd-compressed Linux kernel modules as used by OpenSUSE and maybe
other distros in future.

Note that zstd becomes a required package, but it is widely available
in current Linux distros.

The package names come from https://pkgs.org/download/zstd and my own
research.

(cherry picked from commit 0e784824e8)

.gitignore

@@ -448,6 +448,7 @@ Makefile.in
 /test-data/files/initrd-x86_64.img
 /test-data/files/initrd-x86_64.img.gz
 /test-data/files/lib-i586.so.xz
+/test-data/files/lib-i586.so.zst
 /test-data/files/test-grep.txt.gz
 /test-data/phony-guests/archlinux.img
 /test-data/phony-guests/blank-*.img

appliance/packagelist.in

@@ -48,6 +48,7 @@ ifelse(REDHAT,1,
   vim-minimal
   xz
   zfs-fuse
+  zstd
 )
 
 ifelse(DEBIAN,1,
@@ -88,6 +89,7 @@ dnl iproute has been renamed to iproute2
   vim-tiny
   xz-utils
   zfs-fuse
+  zstd
   uuid-runtime
 )
 
@@ -115,6 +117,7 @@ ifelse(ARCHLINUX,1,
   systemd
   vim
   xz
+  zstd
 )
 
 ifelse(SUSE,1,
@@ -140,6 +143,7 @@ ifelse(SUSE,1,
   systemd-sysvinit
   vim
   xz
+  zstd
 )
 
 ifelse(FRUGALWARE,1,
@@ -185,6 +189,7 @@ ifelse(MAGEIA,1,
   systemd /* for /sbin/reboot and udevd */
   vim-minimal
   xz
+  zstd
 )
 
 ifelse(OPENMANDRIVA,1,
@@ -203,6 +208,7 @@ ifelse(OPENMANDRIVA,1,
   systemd /* for /sbin/reboot and udevd */
   vim-minimal
   xz
+  zstd
 )
 
 include(guestfsd.deps)

daemon/filearch.ml

@@ -106,6 +106,7 @@ and cpio_arch magic orig_path path =
     if String.find magic "gzip" >= 0 then "zcat"
     else if String.find magic "bzip2" >= 0 then "bzcat"
     else if String.find magic "XZ compressed" >= 0 then "xzcat"
+    else if String.find magic "Zstandard compressed" >= 0 then "zstdcat"
     else "cat" in
 
   let tmpdir = Mkdtemp.temp_dir "filearch" in

docs/guestfs-building.pod

@@ -172,6 +172,10 @@ I<Required>.
 
 I<Required>.
 
+=item zstd
+
+I<Required>.
+
 =item Jansson E<ge> 2.7
 
 I<Required>.

generator/actions_core.ml

@@ -9373,6 +9373,8 @@ with large files, such as the resulting squashfs will be over 3GB big." };
         [["file_architecture"; "/bin-x86_64-dynamic.gz"]], "x86_64"), [];
       InitISOFS, Always, TestResultString (
         [["file_architecture"; "/lib-i586.so.xz"]], "i386"), [];
+      InitISOFS, Always, TestResultString (
+        [["file_architecture"; "/lib-i586.so.zst"]], "i386"), [];
     ];
     shortdesc = "detect the architecture of a binary file";
     longdesc = "\

m4/guestfs-progs.m4

@@ -95,6 +95,10 @@ AC_PATH_PROGS([XZCAT],[xzcat],[no])
 test "x$XZCAT" = "xno" && AC_MSG_ERROR([xzcat must be installed])
 AC_DEFINE_UNQUOTED([XZCAT],["$XZCAT"],[Name of xzcat program.])
 
+dnl Check for zstdcat (required).
+AC_PATH_PROGS([ZSTDCAT],[zstdcat],[no])
+test "x$ZSTDCAT" = "xno" && AC_MSG_ERROR([zstdcat must be installed])
+
 dnl (f)lex and bison for virt-builder (required).
 dnl XXX Could be optional with some work.
 AC_PROG_LEX

test-data/Makefile.am

@@ -85,6 +85,7 @@ image_files = \
 	files/initrd-x86_64.img \
 	files/initrd-x86_64.img.gz \
 	files/lib-i586.so.xz \
+	files/lib-i586.so.zst \
 	files/test-grep.txt.gz
 
 noinst_DATA = test.iso

test-data/files/Makefile.am

@@ -40,6 +40,7 @@ noinst_DATA = \
 	initrd-x86_64.img \
 	initrd-x86_64.img.gz \
 	lib-i586.so.xz \
+	lib-i586.so.zst \
 	test-grep.txt.gz
 
 CLEANFILES += $(noinst_DATA)
@@ -116,3 +117,8 @@ lib-i586.so.xz: $(top_srcdir)/test-data/binaries/lib-i586.so
 	rm -f $@ $@-t
 	xz -c $< > $@-t
 	mv $@-t $@
+
+lib-i586.so.zst: $(top_srcdir)/test-data/binaries/lib-i586.so
+	rm -f $@ $@-t
+	zstd -c $< > $@-t
+	mv $@-t $@