compel cli: show includes

1. Add "compel includes" command, to be used for parasite *loading*
   code compilation.

2. Add includes to output of "compel cflags", which is used for parasite
   code compilation.

Now, this patch looks big and complex, this is mostly because we want
compel cli to work for both uninstalled (right from the source tree)
and installed cases. The paths to be printed are quite different for
these two cases, so I had to introduce a wrapper for a non-installed
case. The wrapper sets an environment variable, which compel binary
uses as a path to non-installed file. If this env var is not set,
it means compel is installed so no tricks are needed.

Note the wrapper is only provided for the compel-host binary, as compel
(which differs from compel-host in case of cross-compiling) is not
executed from within the source tree.

Because of the wrapper, the original binary had to be renamed, thus the
changes to Makefiles and .gitignore.

travis-ci: success for More polishing for compel cli
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>

.gitignore

@@ -17,7 +17,7 @@ tags
 TAGS
 Makefile.local
 compel/compel
-compel/compel-host
+compel/compel-host-bin
 images/*.c
 images/*.h
 images/google/protobuf/*.c

Makefile

@@ -222,9 +222,9 @@ $(SOCCR_A): |soccr/built-in.o
 #
 # But note that we're already included
 # the nmk so we can reuse it there.
-criu/%: images/built-in.o compel/plugins/std.built-in.o compel/libcompel.a compel/compel-host $(VERSION_HEADER) .FORCE
+criu/%: images/built-in.o compel/plugins/std.built-in.o compel/libcompel.a compel/compel-host-bin $(VERSION_HEADER) .FORCE
 	$(Q) $(MAKE) $(build)=criu $@
-criu: images/built-in.o compel/plugins/std.built-in.o compel/libcompel.a compel/compel-host $(SOCCR_A) $(VERSION_HEADER)
+criu: images/built-in.o compel/plugins/std.built-in.o compel/libcompel.a compel/compel-host-bin $(SOCCR_A) $(VERSION_HEADER)
 	$(Q) $(MAKE) $(build)=criu all
 .PHONY: criu
 

compel/Makefile

@@ -2,6 +2,7 @@ include $(SRC_DIR)/Makefile.versions
 
 COMPEL_SO_VERSION	:= $(COMPEL_SO_VERSION_MAJOR)$(if $(COMPEL_SO_VERSION_MINOR),.$(COMPEL_SO_VERSION_MINOR))$(if $(COMPEL_SO_VERSION_SUBLEVEL),.$(COMPEL_SO_VERSION_SUBLEVEL))
 COMPEL_SO_VERSION_CODE	:= $(shell expr $(COMPEL_SO_VERSION_MAJOR) \* 65536 \+ $(COMPEL_SO_VERSION_MINOR) \* 256 \+ $(COMPEL_SO_VERSION_SUBLEVEL))
+ccflags-y		+= -DINCLUDEDIR=\"$(INCLUDEDIR)\"
 ccflags-y		+= -iquote compel/arch/$(ARCH)/src/lib/include
 ccflags-y		+= -iquote compel/include
 ccflags-y		+= -iquote compel/plugins/include
@@ -45,8 +46,8 @@ endif
 
 host-ccflags-y		+= $(ccflags-y)
 
-hostprogs-y		+= compel-host
-compel-host-objs	:= $(patsubst %.o,%-host.o,$(obj-y) $(host-lib-y))
+hostprogs-y		+= compel-host-bin
+compel-host-bin-objs	:= $(patsubst %.o,%-host.o,$(obj-y) $(host-lib-y))
 
 ifeq ($(ARCH),x86)
 HOSTCFLAGS_handle-elf-32-host.o += -UCONFIG_X86_64 -DCONFIG_X86_32
@@ -54,7 +55,7 @@ HOSTCFLAGS_handle-elf-32-host.d += -UCONFIG_X86_64 -DCONFIG_X86_32
 endif
 
 cleanup-y		+= compel/compel
-cleanup-y		+= compel/compel-host
+cleanup-y		+= compel/compel-host-bin
 cleanup-y		+= compel/libcompel.so
 
 install: compel/compel compel/$(LIBCOMPEL_SO) compel/$(LIBCOMPEL_A)

compel/compel-host

+#!/bin/sh
+#
+# A wrapper to use compel-host right from the source dir
+# (i.e. when it is not yet installed).
+
+COMPEL_UNINSTALLED_ROOTDIR=$(dirname "$0")
+export COMPEL_UNINSTALLED_ROOTDIR
+exec "${COMPEL_UNINSTALLED_ROOTDIR}/compel-host-bin" "$@"

compel/src/main.c

@@ -48,6 +48,7 @@ static const flags_t flags = {
 };
 
 piegen_opt_t opts = {};
+const char *uninst_root;
 
 static int piegen(void)
 {
@@ -114,7 +115,7 @@ static int usage(int rc) {
 
 	fprintf(out,
 "Usage:\n"
-"  compel [--compat] cflags | ldflags\n"
+"  compel [--compat] includes | cflags | ldflags\n"
 "  compel -f FILE -o FILE -p NAME [-l N] hgen\n"
 "    -f, --file FILE		input (parasite object) file name\n"
 "    -o, --output FILE		output (header) file name\n"
@@ -128,9 +129,35 @@ static int usage(int rc) {
 	return rc;
 }
 
+static void print_includes(void)
+{
+	int i;
+	/* list of standard include dirs (built into C preprocessor) */
+	const char *standard_includes[] = {
+		"/usr/include",
+		"/usr/local/include",
+	};
+
+	/* I am not installed, called via a wrapper */
+	if (uninst_root) {
+		printf("-I %s/include/uapi\n", uninst_root);
+		return;
+	}
+
+	/* I am installed
+	 * Make sure to not print banalities */
+	for (i = 0; i < ARRAY_SIZE(standard_includes); i++)
+		if (strcmp(INCLUDEDIR, standard_includes[i]) == 0)
+			return;
+
+	/* Finally, print our non-standard include path */
+	printf("%s\n", "-I " INCLUDEDIR);
+}
+
 static void print_cflags(bool compat)
 {
 	printf("%s\n", compat ? flags.cflags_compat : flags.cflags);
+	print_includes();
 }
 
 int main(int argc, char *argv[])
@@ -152,6 +179,8 @@ int main(int argc, char *argv[])
 		{ },
 	};
 
+	uninst_root = getenv("COMPEL_UNINSTALLED_ROOTDIR");
+
 	while (1) {
 		idx = -1;
 		opt = getopt_long(argc, argv, short_opts, long_opts, &idx);
@@ -195,6 +224,10 @@ int main(int argc, char *argv[])
 	}
 	action = argv[optind++];
 
+	if (!strcmp(action, "includes")) {
+		print_includes();
+		return 0;
+	}
 	if (!strcmp(action, "cflags")) {
 		print_cflags(compat);
 		return 0;

compel/test/infect/Makefile

@@ -3,7 +3,6 @@ CFLAGS	?= -O2 -g -Wall -Werror
 ARCH	?= x86
 
 COMPEL		:= ../../../compel/compel-host
-COMPEL_IDIR	:= ../../../compel/include/uapi
 COMPEL_PACK_LDS	:= ../../../compel/arch/$(ARCH)/scripts/compel-pack.lds.S
 COMPEL_PLUGINS	:= ../../../compel/plugins
 COMPEL_LIBRARY	:= ../../../compel/libcompel.a
@@ -21,7 +20,7 @@ victim: victim.c
 	$(CC) $(CFLAGS) -o $@ $^
 
 spy: spy.c | parasite.h
-	$(CC) $(CFLAGS) -I$(COMPEL_IDIR) -o $@ $^ $(COMPEL_LIBRARY)
+	$(CC) $(CFLAGS) $(shell $(COMPEL) includes) -o $@ $^ $(COMPEL_LIBRARY)
 
 parasite.h: parasite.po
 	$(COMPEL) hgen -f $^ -l 4		\
@@ -32,4 +31,4 @@ parasite.po: parasite.o $(COMPEL_PLUGINS)/std.built-in.o
 	ld -r -T $(COMPEL_PACK_LDS) -o $@ $^
 
 parasite.o: parasite.c
-	$(CC) $(CFLAGS) -c $(shell $(COMPEL) cflags) -I$(COMPEL_IDIR) -o $@ $^
+	$(CC) $(CFLAGS) -c $(shell $(COMPEL) cflags) -o $@ $^

compel/test/rsys/Makefile

 CC	:= gcc
 CFLAGS	?= -O2 -g -Wall -Werror
 
-COMPEL_IDIR	:= ../../../compel/include/uapi
+COMPEL		:= ../../../compel/compel-host
 COMPEL_LIBRARY	:= ../../../compel/libcompel.a
 
 all: victim spy
@@ -14,4 +14,4 @@ victim: victim.c
 	$(CC) $(CFLAGS) -o $@ $^
 
 spy: spy.c
-	$(CC) $(CFLAGS) -I$(COMPEL_IDIR) -o $@ $^ $(COMPEL_LIBRARY)
+	$(CC) $(CFLAGS) $(shell $(COMPEL) includes) -o $@ $^ $(COMPEL_LIBRARY)

criu/pie/Makefile

@@ -62,7 +62,7 @@ $(obj)/%.built-in.bin.o: $(obj)/%.built-in.o $(obj)/pie.lib.a $(compel_lds)
 	$(call msg-gen, $@)
 	$(Q) $(LD) -r -T $(compel_lds) -o $@ $< $(obj)/pie.lib.a
 
-$(obj)/%-blob.h: $(obj)/%.built-in.bin.o $(SRC_DIR)/compel/compel-host
+$(obj)/%-blob.h: $(obj)/%.built-in.bin.o $(SRC_DIR)/compel/compel-host-bin
 	$(call msg-gen, $@)
 	$(Q) $(SRC_DIR)/compel/compel-host hgen -f $<			\
 		-l 4							\