build: add mounts and excludes for cargo-based builds

Signed-off-by: Ben Cressey <[email protected]>

.gitignore

@@ -5,3 +5,4 @@
 *.tar.*
 /packages/*/*.crate
 **/target/
+/.cargo

Dockerfile

@@ -49,7 +49,10 @@ RUN --mount=target=/host \
         builddep rpmbuild/SPECS/${PACKAGE}.spec
 
 USER builder
-RUN rpmbuild -ba --clean rpmbuild/SPECS/${PACKAGE}.spec
+RUN --mount=source=.cargo,target=/home/builder/.cargo \
+    --mount=type=cache,target=/home/builder/.cache,uid=1000,id=${PACKAGE} \
+    --mount=source=workspaces,target=/home/builder/rpmbuild/BUILD/workspaces \
+    rpmbuild -ba --clean rpmbuild/SPECS/${PACKAGE}.spec
 
 FROM scratch AS rpm
 COPY --from=rpmbuild /home/builder/rpmbuild/RPMS/*/*.rpm /

Makefile

@@ -16,7 +16,8 @@ VARS = $(SPECS:.spec=.makevar)
 PKGS = $(SPECS:.spec=.makepkg)
 
 OUTPUT ?= $(TOPDIR)/build
-OUTVAR := $(shell mkdir -p $(OUTPUT))
+CARGO_HOME ?= $(TOPDIR)/.cargo
+OUTVAR := $(shell mkdir -p $(OUTPUT) $(CARGO_HOME))
 
 ARCH ?= $(shell uname -m)