build: factor out `pluginarchive` function to `src/Makefile.common.inc`

A subsequent patch will need to bundle a plugin in a test executable,
requiring the same command line used by the CLI to bundle plugins in the
`babeltrace2` executable, when `--enable-built-in-plugins` is used.
Move the `pluginarchive` "function" and `PLUGINS_PATH` definition to a
new file, `src/Makefile.common.inc`, and include that file from
`src/cli/Makefile.am`.

Change-Id: I36a8d6191deb82e5bceab3f5b038f69626ecdfe2
Signed-off-by: Simon Marchi <simon.marchi@efficios.com>
Reviewed-on: https://review.lttng.org/c/babeltrace/+/11830
Tested-by: jenkins <jenkins@lttng.org>
Reviewed-by: Michael Jeanson <mjeanson@efficios.com>
Reviewed-by: Philippe Proulx <eeppeliteloop@gmail.com>

diff --git a/src/Makefile.common.inc b/src/Makefile.common.inc
new file mode 100644 (file)
index 0000000..0d71e95
--- /dev/null
+++ b/src/Makefile.common.inc
@@ -0,0 +1,21 @@
+# SPDX-FileCopyrightText: 2017-2024 EfficiOS, Inc.
+# SPDX-License-Identifier: MIT
+
+# Path to the plugins build directory.
+PLUGINS_PATH = $(abs_top_builddir)/src/plugins
+
+# Takes a plugin name and outputs the needed LDFLAGS to embed it.
+#
+# The --whole-archive option is important here. From the GNU linker's
+# documentation:
+#
+#     For each archive mentioned on the command line after the
+#     --whole-archive option, include every object file in the archive in
+#     the link, rather than searching the archive for the required object
+#     files.
+#
+# In our case, we find the plugins thanks to special sections in the
+# binary that are filled by plugin objects. If the linker discards those
+# symbols because the CLI does not use them directly, the CLI reports
+# no plugins found (plugins are effectively not embedded).
+pluginarchive = $(LD_WHOLE_ARCHIVE)$(PLUGINS_PATH)/$(1)/.libs/babeltrace-plugin-$(1).a$(LD_NO_WHOLE_ARCHIVE)

diff --git a/src/cli/Makefile.am b/src/cli/Makefile.am
index 4731375b9295f7e45d308042c2b30f433d407b06..4525487809ef4f7fc8643708d8c52a5a1aef6c3e 100644 (file)
--- a/src/cli/Makefile.am
+++ b/src/cli/Makefile.am
@@ -1,7 +1,8 @@
 # SPDX-FileCopyrightText: 2019-2023 EfficiOS, Inc.
 # SPDX-License-Identifier: MIT
 
-PLUGINS_PATH = $(abs_top_builddir)/src/plugins
+include $(top_srcdir)/src/Makefile.common.inc
+
 LTTNG_UTILS_PLUGIN_PATH =
 
 if ENABLE_DEBUG_INFO
@@ -69,21 +70,6 @@ babeltrace2_bin_LDADD = \
        $(top_builddir)/src/ctfser/libctfser.la
 
 if ENABLE_BUILT_IN_PLUGINS
-# Takes a plugin name and outputs the needed LDFLAGS to embed it.
-#
-# The --whole-archive option is important here. From the GNU linker's
-# documentation:
-#
-#     For each archive mentioned on the command line after the
-#     --whole-archive option, include every object file in the archive in
-#     the link, rather than searching the archive for the required object
-#     files.
-#
-# In our case, we find the plugins thanks to special sections in the
-# binary that are filled by plugin objects. If the linker discards those
-# symbols because the CLI does not use them directly, the CLI reports
-# no plugins found (plugins are effectively not embedded).
-pluginarchive = $(LD_WHOLE_ARCHIVE)$(PLUGINS_PATH)/$(1)/.libs/babeltrace-plugin-$(1).a$(LD_NO_WHOLE_ARCHIVE)
 
 # Built-in plugins
 babeltrace2_bin_LDFLAGS += $(call pluginarchive,ctf)