rust: Fix warnings issued by newer rustc

Warnings were issued because bindgen generated prototypes for all
functions, including standard ones like memcpy. The solution used
in this patch is to narrow the number of generated prototypes to
the bare minimum.

Variables were never generated, so the filter parameter in
rust-regen.sh was basically a no-op. Instead, the filter is now
used to allowlist types and functions. This results in generating
only prototypes with a given prefix (luckily, all Corosync
types/functions in headers are properly prefixed). This also
means all blocklists could be removed.

Lastly (and most importantly), the ./configure detected bindgen
path is now passed to rust-regen.sh, so it calls the correct
binary instead of just the first one found in the $PATH.

Signed-off-by: Jan Friesse <jfriesse@redhat.com>
Reviewed-by: Fabio M. Di Nitto <fdinitto@redhat.com>

bindings/rust/Makefile.am

@@ -37,19 +37,19 @@ RUST_BUILT_SRCS		= \
 			  src/sys/cmap.rs
 
 src/sys/cpg.rs: cargo-tree-prep ../../include/corosync/cpg.h
-	$(top_srcdir)/build-aux/rust-regen.sh $(top_srcdir)/include/corosync/cpg.h $@ CPG --blocklist-function=inet6.* --blocklist-function==.*etsourcefilter -- -I$(top_srcdir)/include
+	$(top_srcdir)/build-aux/rust-regen.sh $(BINDGEN) $(top_srcdir)/include/corosync/cpg.h $@ cpg -- -I$(top_srcdir)/include
 
 src/sys/cfg.rs: cargo-tree-prep ../../include/corosync/cfg.h
-	$(top_srcdir)/build-aux/rust-regen.sh $(top_srcdir)/include/corosync/cfg.h $@ CFG --blocklist-function=inet6.* --blocklist-function=.*etsourcefilter -- -I$(top_srcdir)/include
+	$(top_srcdir)/build-aux/rust-regen.sh $(BINDGEN) $(top_srcdir)/include/corosync/cfg.h $@ corosync_cfg -- -I$(top_srcdir)/include
 
 src/sys/quorum.rs: cargo-tree-prep ../../include/corosync/quorum.h
-	$(top_srcdir)/build-aux/rust-regen.sh $(top_srcdir)/include/corosync/quorum.h $@ QUORUM -- -I$(top_srcdir)/include
+	$(top_srcdir)/build-aux/rust-regen.sh $(BINDGEN) $(top_srcdir)/include/corosync/quorum.h $@ quorum -- -I$(top_srcdir)/include
 
 src/sys/votequorum.rs: cargo-tree-prep ../../include/corosync/votequorum.h
-	$(top_srcdir)/build-aux/rust-regen.sh $(top_srcdir)/include/corosync/votequorum.h $@ VOTEQUORUM -- -I$(top_srcdir)/include
+	$(top_srcdir)/build-aux/rust-regen.sh $(BINDGEN) $(top_srcdir)/include/corosync/votequorum.h $@ votequorum -- -I$(top_srcdir)/include
 
 src/sys/cmap.rs: cargo-tree-prep ../../include/corosync/cmap.h
-	$(top_srcdir)/build-aux/rust-regen.sh $(top_srcdir)/include/corosync/cmap.h $@ CMAP -- -I$(top_srcdir)/include $(LIBQB_CFLAGS)
+	$(top_srcdir)/build-aux/rust-regen.sh $(BINDGEN) $(top_srcdir)/include/corosync/cmap.h $@ cmap -- -I$(top_srcdir)/include $(LIBQB_CFLAGS)
 
 all-local: target/$(RUST_TARGET_DIR)/cpg.rlib \
 	target/$(RUST_TARGET_DIR)/cfg.rlib \

build-aux/rust-regen.sh

@@ -11,18 +11,18 @@
 # Regerate the FFI bindings in src/sys from the current headers
 #
 
-srcheader="$1"
-dstrs="$2"
-filter="$3"
-shift; shift; shift
+bindgen="$1"
+srcheader="$2"
+dstrs="$3"
+filter="$4"
+shift 4
 
-bindgen \
+"$bindgen" \
 	--no-prepend-enum-name \
 	--no-layout-tests \
 	--no-doc-comments \
 	--generate functions,types \
 	--fit-macro-constant-types \
-	--allowlist-var=$filter.*  \
-	--allowlist-type=.* \
-	--allowlist-function=.* \
-	$srcheader -o $dstrs "$@"
+	--allowlist-type="^(${filter}_.*)" \
+	--allowlist-function="^(${filter}_.*)" \
+	"$srcheader" -o "$dstrs" "$@"