From 924c0ff17fca4f4527e8076f8d6b88dd39176dc8 Mon Sep 17 00:00:00 2001
From: Andrew Cooper <andrew.cooper3@citrix.com>
Date: Tue, 5 May 2026 12:42:00 +0100
Subject: [PATCH] tools/configure: Detect the presence of liblz4
MIME-Version: 1.0
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As with other compression libraries, group liblz4 into ZLIB_{CFLAGS,LIBS}.

Add the packages to the Debian Trixie build containers for coverage.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
---
 automation/build/debian/13-arm64v8.dockerfile |  1 +
 automation/build/debian/13-x86_64.dockerfile  |  1 +
 tools/configure                               | 79 +++++++++++++++++++
 tools/configure.ac                            |  4 +
 4 files changed, 85 insertions(+)

diff --git a/automation/build/debian/13-arm64v8.dockerfile b/automation/build/debian/13-arm64v8.dockerfile
index b9062ee8b4..ee9bb841eb 100644
--- a/automation/build/debian/13-arm64v8.dockerfile
+++ b/automation/build/debian/13-arm64v8.dockerfile
@@ -28,6 +28,7 @@ RUN <<EOF
         wget
         # libxenguest dombuilder
         libbz2-dev
+        liblz4-dev
         liblzma-dev
         liblzo2-dev
         libzstd-dev
diff --git a/automation/build/debian/13-x86_64.dockerfile b/automation/build/debian/13-x86_64.dockerfile
index 2c6c9d4a50..e0a7225952 100644
--- a/automation/build/debian/13-x86_64.dockerfile
+++ b/automation/build/debian/13-x86_64.dockerfile
@@ -29,6 +29,7 @@ RUN <<EOF
         wget
         # libxenguest dombuilder
         libbz2-dev
+        liblz4-dev
         liblzma-dev
         liblzo2-dev
         libzstd-dev
diff --git a/tools/configure b/tools/configure
index 6f69b0b526..bf14864cfb 100755
--- a/tools/configure
+++ b/tools/configure
@@ -669,6 +669,8 @@ PTHREAD_CFLAGS
 EXTFS_LIBS
 ZLIB_LIBS
 ZLIB_CFLAGS
+liblz4_LIBS
+liblz4_CFLAGS
 libzstd_LIBS
 libzstd_CFLAGS
 FETCHER
@@ -885,6 +887,8 @@ pixman_CFLAGS
 pixman_LIBS
 libzstd_CFLAGS
 libzstd_LIBS
+liblz4_CFLAGS
+liblz4_LIBS
 libjsonc_CFLAGS
 libjsonc_LIBS
 LIBNL3_CFLAGS
@@ -1638,6 +1642,9 @@ Some influential environment variables:
               C compiler flags for libzstd, overriding pkg-config
   libzstd_LIBS
               linker flags for libzstd, overriding pkg-config
+  liblz4_CFLAGS
+              C compiler flags for liblz4, overriding pkg-config
+  liblz4_LIBS linker flags for liblz4, overriding pkg-config
   libjsonc_CFLAGS
               C compiler flags for libjsonc, overriding pkg-config
   libjsonc_LIBS
@@ -9458,6 +9465,78 @@ printf "%s\n" "yes" >&6; }
      ZLIB_LIBS="$ZLIB_LIBS $libzstd_LIBS"
 fi
 
+pkg_failed=no
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for liblz4" >&5
+printf %s "checking for liblz4... " >&6; }
+
+if test -n "$liblz4_CFLAGS"; then
+    pkg_cv_liblz4_CFLAGS="$liblz4_CFLAGS"
+ elif test -n "$PKG_CONFIG"; then
+    if test -n "$PKG_CONFIG" && \
+    { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"liblz4\""; } >&5
+  ($PKG_CONFIG --exists --print-errors "liblz4") 2>&5
+  ac_status=$?
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; then
+  pkg_cv_liblz4_CFLAGS=`$PKG_CONFIG --cflags "liblz4" 2>/dev/null`
+		      test "x$?" != "x0" && pkg_failed=yes
+else
+  pkg_failed=yes
+fi
+ else
+    pkg_failed=untried
+fi
+if test -n "$liblz4_LIBS"; then
+    pkg_cv_liblz4_LIBS="$liblz4_LIBS"
+ elif test -n "$PKG_CONFIG"; then
+    if test -n "$PKG_CONFIG" && \
+    { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"liblz4\""; } >&5
+  ($PKG_CONFIG --exists --print-errors "liblz4") 2>&5
+  ac_status=$?
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; then
+  pkg_cv_liblz4_LIBS=`$PKG_CONFIG --libs "liblz4" 2>/dev/null`
+		      test "x$?" != "x0" && pkg_failed=yes
+else
+  pkg_failed=yes
+fi
+ else
+    pkg_failed=untried
+fi
+
+
+
+if test $pkg_failed = yes; then
+   	{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+
+if $PKG_CONFIG --atleast-pkgconfig-version 0.20; then
+        _pkg_short_errors_supported=yes
+else
+        _pkg_short_errors_supported=no
+fi
+        if test $_pkg_short_errors_supported = yes; then
+	        liblz4_PKG_ERRORS=`$PKG_CONFIG --short-errors --print-errors --cflags --libs "liblz4" 2>&1`
+        else
+	        liblz4_PKG_ERRORS=`$PKG_CONFIG --print-errors --cflags --libs "liblz4" 2>&1`
+        fi
+	# Put the nasty error message in config.log where it belongs
+	echo "$liblz4_PKG_ERRORS" >&5
+
+	true
+elif test $pkg_failed = untried; then
+     	{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+	true
+else
+	liblz4_CFLAGS=$pkg_cv_liblz4_CFLAGS
+	liblz4_LIBS=$pkg_cv_liblz4_LIBS
+        { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
+	ZLIB_CFLAGS="$ZLIB_CFLAGS -DHAVE_LZ4 $liblz4_CFLAGS"
+     ZLIB_LIBS="$ZLIB_LIBS $liblz4_LIBS"
+fi
+
 
 
 ac_fn_c_check_header_compile "$LINENO" "ext2fs/ext2fs.h" "ac_cv_header_ext2fs_ext2fs_h" "$ac_includes_default"
diff --git a/tools/configure.ac b/tools/configure.ac
index ecd45e782e..74b9f56025 100644
--- a/tools/configure.ac
+++ b/tools/configure.ac
@@ -403,6 +403,10 @@ PKG_CHECK_MODULES([libzstd], [libzstd],
     [ZLIB_CFLAGS="$ZLIB_CFLAGS -DHAVE_ZSTD $libzstd_CFLAGS"
      ZLIB_LIBS="$ZLIB_LIBS $libzstd_LIBS"],
     [true])
+PKG_CHECK_MODULES([liblz4], [liblz4],
+    [ZLIB_CFLAGS="$ZLIB_CFLAGS -DHAVE_LZ4 $liblz4_CFLAGS"
+     ZLIB_LIBS="$ZLIB_LIBS $liblz4_LIBS"],
+    [true])
 AC_SUBST([ZLIB_CFLAGS])
 AC_SUBST([ZLIB_LIBS])
 AX_CHECK_EXTFS