protobuf: Start switching our image entries to Google's protobuf

A short story -- there were a long conversation on which format should
be used to keep checkpointed data on disk image. We ended up in using
Google's Protocol Buffers (see https://developers.google.com/protocol-buffers/
for detailed description). Thus image entries should be convered to PB.

This patch converts fdinfo_entry to PB "message fdinfo_entry".

Build note: one should have protobuf and protobuf-c installed to be able
to build crtools.

 - http://code.google.com/p/protobuf/
 - http://code.google.com/p/protobuf-c/

Inspired-by: Pavel Emelianov <xemul@parallels.com>
Inspired-by: Kinsbursky Stanislav <skinsbursky@openvz.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Makefile

@@ -3,7 +3,7 @@ include Makefile.inc
 CFLAGS		+= -I./include
 CFLAGS		+= -O0 -ggdb3
 
-LIBS		+= -lrt -lpthread
+LIBS		+= -lrt -lpthread -lprotobuf-c
 
 DEFINES		+= -D_FILE_OFFSET_BITS=64
 DEFINES		+= -D_GNU_SOURCE
@@ -61,6 +61,8 @@ OBJS		+= inotify.o
 OBJS		+= pstree.o
 OBJS		+= protobuf.o
 
+PROTOBUF-LIB	:= protobuf/protobuf-lib.o
+
 DEPS		:= $(patsubst %.o,%.d,$(OBJS))
 
 MAKEFLAGS	+= --no-print-directory
@@ -69,13 +71,16 @@ include Makefile.syscall
 include Makefile.pie
 
 .PHONY: all test-legacy zdtm test rebuild clean distclean tags cscope	\
-	docs help pie
+	docs help pie protobuf
 
-all: pie
+all: protobuf pie
 	$(Q) $(MAKE) $(PROGRAM)
 
 pie: $(PIE-GEN)
 
+protobuf:
+	$(Q) $(MAKE) -C protobuf/ all
+
 %.o: %.c
 	$(E) "  CC      " $@
 	$(Q) $(CC) -c $(CFLAGS) $< -o $@
@@ -92,7 +97,7 @@ pie: $(PIE-GEN)
 	$(E) "  DEP     " $@
 	$(Q) $(CC) -M -MT $@ -MT $(patsubst %.d,%.o,$@) $(CFLAGS) $< -o $@
 
-$(PROGRAM): $(OBJS) $(SYS-OBJ)
+$(PROGRAM): $(OBJS) $(SYS-OBJ) $(PROTOBUF-LIB)
 	$(E) "  LINK    " $@
 	$(Q) $(CC) $(CFLAGS) $^ $(LIBS) -o $@
 
@@ -121,6 +126,7 @@ clean: cleanpie cleansyscall
 	$(Q) $(RM) -f ./*.bin
 	$(Q) $(RM) -f ./$(PROGRAM)
 	$(Q) $(RM) -rf ./test/dump/
+	$(Q) $(MAKE) -C protobuf/ clean
 	$(Q) $(MAKE) -C test/legacy clean
 	$(Q) $(MAKE) -C test/zdtm cleandep
 	$(Q) $(MAKE) -C test/zdtm clean

cr-dump.c

@@ -45,6 +45,9 @@
 #include "inotify.h"
 #include "pstree.h"
 
+#include "protobuf.h"
+#include "protobuf/fdinfo.pb-c.h"
+
 #ifndef CONFIG_X86_64
 # error No x86-32 support yet
 #endif
@@ -130,7 +133,7 @@ u32 make_gen_id(const struct fd_parms *p)
 int do_dump_gen_file(struct fd_parms *p, int lfd,
 		const struct fdtype_ops *ops, const struct cr_fdset *cr_fdset)
 {
-	struct fdinfo_entry e;
+	FdinfoEntry e = FDINFO_ENTRY__INIT;
 	int ret = -1;
 
 	e.type	= ops->type;
@@ -143,17 +146,12 @@ int do_dump_gen_file(struct fd_parms *p, int lfd,
 		ret = ops->dump(lfd, e.id, p);
 
 	if (ret < 0)
-		goto err;
+		return -1;
 
 	pr_info("fdinfo: type: 0x%2x flags: 0x%4x pos: 0x%8lx fd: %d\n",
 		ops->type, p->flags, p->pos, p->fd);
 
-	if (write_img(fdset_fd(cr_fdset, CR_FD_FDINFO), &e))
+	return pb_write(fdset_fd(cr_fdset, CR_FD_FDINFO), &e, fdinfo_entry);
-		goto err;
-
-	ret = 0;
-err:
-	return ret;
 }
 
 static int dump_task_exe_link(pid_t pid, struct mm_entry *mm)

cr-show.c

@@ -24,6 +24,9 @@
 #include "ipc_ns.h"
 #include "pstree.h"
 
+#include "protobuf.h"
+#include "protobuf/fdinfo.pb-c.h"
+
 #define DEF_PAGES_PER_LINE	6
 
 #ifndef CONFIG_X86_64
@@ -77,21 +80,16 @@ static char *fdtype2s(u8 type)
 
 void show_files(int fd_files, struct cr_options *o)
 {
-	struct fdinfo_entry e;
-
 	pr_img_head(CR_FD_FDINFO);
 
 	while (1) {
-		int ret;
+		FdinfoEntry *e;
-
+		int ret = pb_read_eof(fd_files, &e, fdinfo_entry);
-		ret = read_img_eof(fd_files, &e);
 		if (ret <= 0)
 			goto out;
-
+		pr_msg("type: %-5s fd: %-5d id: %#x flags %#x\n",
-		pr_msg("type: %-5s fd: %-5d id: %#x flags %#x",
+		       fdtype2s(e->type), e->fd, e->id, e->flags);
-		       fdtype2s(e.type), e.fd, e.id, e.flags);
+		fdinfo_entry__free_unpacked(e, NULL);
-
-		pr_msg("\n");
 	}
 
 out:

file-ids.c

@@ -30,7 +30,7 @@ u32 fd_id_generate_special(void)
 	return fd_tree.subid++;
 }
 
-int fd_id_generate(pid_t pid, struct fdinfo_entry *fe)
+int fd_id_generate(pid_t pid, FdinfoEntry *fe)
 {
 	u32 id;
 	struct kid_elem e;

files.c

@@ -24,6 +24,8 @@
 #include "sockets.h"
 #include "pstree.h"
 
+#include "protobuf.h"
+
 static struct fdinfo_list_entry *fdinfo_list;
 static int nr_fdinfo_list;
 
@@ -71,7 +73,7 @@ struct file_desc *find_file_desc_raw(int type, u32 id)
 	return NULL;
 }
 
-static inline struct file_desc *find_file_desc(struct fdinfo_entry *fe)
+static inline struct file_desc *find_file_desc(FdinfoEntry *fe)
 {
 	return find_file_desc_raw(fe->type, fe->id);
 }
@@ -152,7 +154,7 @@ int rst_file_params(int fd, fown_t *fown, int flags)
 	return 0;
 }
 
-static int collect_fd(int pid, struct fdinfo_entry *e, struct rst_info *rst_info)
+static int collect_fd(int pid, FdinfoEntry *e, struct rst_info *rst_info)
 {
 	struct fdinfo_list_entry *l, *le = &fdinfo_list[nr_fdinfo_list];
 	struct file_desc *fdesc;
@@ -206,19 +208,17 @@ int prepare_fd_pid(int pid, struct rst_info *rst_info)
 	}
 
 	while (1) {
-		struct fdinfo_entry *e = xmalloc(sizeof(*e));
+		FdinfoEntry *e;
-		if (!e) {
-			ret = -1;
-			break;
-		}
 
-		ret = read_img_eof(fdinfo_fd, e);
+		ret = pb_read_eof(fdinfo_fd, &e, fdinfo_entry);
 		if (ret <= 0)
 			break;
 
 		ret = collect_fd(pid, e, rst_info);
-		if (ret < 0)
+		if (ret < 0) {
+			fdinfo_entry__free_unpacked(e, NULL);
 			break;
+		}
 	}
 
 	close(fdinfo_fd);
@@ -255,7 +255,7 @@ static void transport_name_gen(struct sockaddr_un *addr, int *len,
 	*addr->sun_path = '\0';
 }
 
-static int should_open_transport(struct fdinfo_entry *fe, struct file_desc *fd)
+static int should_open_transport(FdinfoEntry *fe, struct file_desc *fd)
 {
 	if (fd->ops->want_transport)
 		return fd->ops->want_transport(fe, fd);
@@ -326,7 +326,7 @@ int send_fd_to_peer(int fd, struct fdinfo_list_entry *fle, int tsk)
 	return send_fd(tsk, &saddr, len, fd);
 }
 
-static int open_fd(int pid, struct fdinfo_entry *fe, struct file_desc *d)
+static int open_fd(int pid, FdinfoEntry *fe, struct file_desc *d)
 {
 	int tmp;
 	int sock;
@@ -383,7 +383,7 @@ static int open_fd(int pid, struct fdinfo_entry *fe, struct file_desc *d)
 	return 0;
 }
 
-static int receive_fd(int pid, struct fdinfo_entry *fe, struct file_desc *d)
+static int receive_fd(int pid, FdinfoEntry *fe, struct file_desc *d)
 {
 	int tmp;
 	struct fdinfo_list_entry *fle;

include/file-ids.h

@@ -5,6 +5,8 @@
 #include "types.h"
 #include "rbtree.h"
 
+#include "../protobuf/fdinfo.pb-c.h"
+
 #define FD_PID_INVALID		(-2U)
 #define FD_DESC_INVALID		(-3U)
 
@@ -12,7 +14,7 @@
 	(((u32)(dev) ^ (u32)(ino) ^ (u32)(pos)))
 
 struct fdinfo_entry;
-extern int fd_id_generate(pid_t pid, struct fdinfo_entry *fe);
+extern int fd_id_generate(pid_t pid, FdinfoEntry *fe);
 extern u32 fd_id_generate_special(void);
 extern void fd_id_show_tree(void);
 

include/files.h

@@ -7,6 +7,8 @@
 #include "list.h"
 #include "image.h"
 
+#include "../protobuf/fdinfo.pb-c.h"
+
 struct pstree_item;
 struct file_desc;
 struct cr_fdset;
@@ -38,13 +40,13 @@ struct fdinfo_list_entry {
 	struct list_head	ps_list;
 	int			pid;
 	futex_t			real_pid;
-	struct fdinfo_entry	*fe;
+	FdinfoEntry		*fe;
 };
 
 struct file_desc_ops {
 	unsigned int		type;
 	int			(*open)(struct file_desc *d);
-	int			(*want_transport)(struct fdinfo_entry *fe, struct file_desc *d);
+	int			(*want_transport)(FdinfoEntry *fe, struct file_desc *d);
 };
 
 struct file_desc {

include/image.h

@@ -131,13 +131,6 @@ struct inotify_file_entry {
 	fown_t	fown;
 } __packed;
 
-struct fdinfo_entry {
-	u32	fd;
-	u8	type;
-	u8	flags;
-	u32	id;
-} __packed;
-
 struct fs_entry {
 	u32	cwd_id;
 	u32	root_id;

include/sockets.h

@@ -9,7 +9,6 @@
 
 struct fdinfo_list_entry;
 struct sk_opts_entry;
-struct fdinfo_entry;
 struct cr_options;
 struct file_desc;
 struct fd_parms;

pipes.c

@@ -294,7 +294,7 @@ static int open_pipe(struct file_desc *d)
 	return tmp;
 }
 
-static int want_transport(struct fdinfo_entry *fe, struct file_desc *d)
+static int want_transport(FdinfoEntry *fe, struct file_desc *d)
 {
 	struct pipe_info *pi;
 

protobuf/Makefile

@@ -0,0 +1,51 @@
+-include ../Makefile.inc
+
+CFLAGS		+= -I./include
+CFLAGS		+= -O0 -ggdb3
+
+DEFINES		+= -D_FILE_OFFSET_BITS=64
+DEFINES		+= -D_GNU_SOURCE
+
+ifneq ($(WERROR),0)
+	WARNINGS += -Werror
+endif
+
+ifeq ($(DEBUG),1)
+	DEFINES += -DCR_DEBUG
+endif
+
+WARNINGS	+= -Wall
+CFLAGS		+= $(WARNINGS) $(DEFINES)
+
+LIBRARY		:= protobuf-lib.o
+
+PROTO_FILES	+= fdinfo.proto
+
+HDRS	:= $(patsubst %.proto,%.pb-c.h,$(PROTO_FILES))
+SRCS	:= $(patsubst %.proto,%.pb-c.c,$(PROTO_FILES))
+OBJS	:= $(patsubst %.c,%.o,$(SRCS))
+
+.DEFAULT_GOAL	:= all
+
+%.pb-c.c: %.proto
+	$(E) "  PROTOBUF "$@
+	$(Q) protoc-c --c_out=./ $<
+
+%.o: %.c
+	$(E) "  CC       "$@
+	$(Q) $(CC) -c $(CFLAGS) $< -o $@
+
+.SECONDARY:
+
+$(LIBRARY): $(OBJS)
+	$(E) "  LINK     "$@
+	$(Q) ld -r -o $@ $(OBJS)
+
+.PHONY: all clean
+
+all: $(LIBRARY)
+
+clean:
+	$(E) "  CLEAN PROTOBUF"
+	$(Q) rm -f $(SRCS) $(HDRS) $(OBJS) $(LIBRARY)
+

protobuf/fdinfo.proto

@@ -0,0 +1,6 @@
+message fdinfo_entry {
+	required uint32	id	= 1;
+	required uint32	flags	= 2;
+	required uint32	type	= 3;
+	required uint32	fd	= 4;
+}

sk-unix.c

@@ -573,7 +573,7 @@ done:
 	return 0;
 }
 
-static int unixsk_should_open_transport(struct fdinfo_entry *fe,
+static int unixsk_should_open_transport(FdinfoEntry *fe,
 				struct file_desc *d)
 {
 	struct unix_sk_info *ui;