devtools/decodemsg: new tool.

$ ./devtools/decodemsg 00110000000000000000000000000000000000000000000000000000000000000000000e496e7465726e616c206572726f72
WIRE_ERROR:
channel_id=0000000000000000000000000000000000000000000000000000000000000000
data=[Internal error]

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

devtools/Makefile

@@ -1,7 +1,9 @@
-DEVTOOLS_CLI_SRC := devtools/bolt11-cli.c
-DEVTOOLS_CLI_OBJS := $(DEVTOOLS_CLI_SRC:.c=.o)
+DEVTOOLS_SRC := devtools/gen_print_wire.c devtools/print_wire.c
+DEVTOOLS_OBJS := $(DEVTOOLS_SRC:.c=.o)
+DEVTOOLS_TOOL_SRC := devtools/bolt11-cli.c devtools/decodemsg.c
+DEVTOOLS_TOOL_OBJS := $(DEVTOOLS_TOOL_SRC:.c=.o)
 
-DEVTOOLS_CLI_COMMON_OBJS :=			\
+DEVTOOLS_COMMON_OBJS :=				\
 	common/bech32.o				\
 	common/bolt11.o				\
 	common/hash_u5.o			\
@@ -9,17 +11,26 @@ DEVTOOLS_CLI_COMMON_OBJS :=			\
 	common/utils.o				\
 	common/version.o
 
-devtools-all: devtools/bolt11-cli
+devtools-all: devtools/bolt11-cli devtools/decodemsg
 
-devtools/bolt11-cli: $(DEVTOOLS_CLI_OBJS) $(DEVTOOLS_CLI_COMMON_OBJS) $(JSMN_OBJS) $(CCAN_OBJS) $(BITCOIN_OBJS) wire/fromwire.o wire/towire.o
+devtools/gen_print_wire.h: $(WIRE_GEN) wire/gen_peer_wire_csv
+	$(WIRE_GEN) --bolt --printwire --header $@ wire_type < wire/gen_peer_wire_csv > $@
 
-$(DEVTOOLS_CLI_OBJS): wire/wire.h
+devtools/gen_print_wire.c: $(WIRE_GEN) wire/gen_peer_wire_csv
+	$(WIRE_GEN) --bolt --printwire ${@:.c=.h} wire_type < wire/gen_peer_wire_csv > $@
+
+devtools/bolt11-cli: $(DEVTOOLS_OBJS) $(DEVTOOLS_COMMON_OBJS) $(JSMN_OBJS) $(CCAN_OBJS) $(BITCOIN_OBJS) wire/fromwire.o wire/towire.o devtools/bolt11-cli.o
+
+devtools/decodemsg: $(DEVTOOLS_OBJS) $(DEVTOOLS_COMMON_OBJS) $(JSMN_OBJS) $(CCAN_OBJS) $(BITCOIN_OBJS) wire/fromwire.o wire/towire.o devtools/decodemsg.o
+
+$(DEVTOOLS_OBJS) $(DEVTOOLS_TOOL_OBJS): wire/wire.h devtools/gen_print_wire.h
+devtools/gen_print_wire.o: devtools/gen_print_wire.h wire/gen_peer_wire.h
 
 # Make sure these depend on everything.
-ALL_PROGRAMS += devtools/bolt11-cli
-ALL_OBJS += $(DEVTOOLS_CLI_OBJS)
+ALL_PROGRAMS += devtools/bolt11-cli devtools/decodemsg
+ALL_OBJS += $(DEVTOOLS_OBJS) $(DEVTOOLS_TOOL_OBJS)
 
-check-source: $(DEVTOOLS_CLI_SRC:%=check-src-include-order/%)
+check-source: $(DEVTOOLS_SRC:%=check-src-include-order/%) $(DEVTOOLS_TOOLS_SRC:%=check-src-include-order/%)
 
 clean: devtools-clean
 

devtools/decodemsg.c

@@ -0,0 +1,9 @@
+#include <common/utils.h>
+#include <devtools/gen_print_wire.h>
+
+int main(int argc, char *argv[])
+{
+	u8 *m = tal_hexdata(NULL, argv[1], strlen(argv[1]));
+	print_message(m);
+	return 0;
+}

devtools/print_wire.c

@@ -0,0 +1,60 @@
+#include <common/type_to_string.h>
+#include <devtools/print_wire.h>
+#include <inttypes.h>
+#include <stdio.h>
+
+void printwire_u8(const u8 *v)
+{
+	printf("%u", *v);
+}
+
+void printwire_u16(const u16 *v)
+{
+	printf("%u", *v);
+}
+
+void printwire_u32(const u32 *v)
+{
+	printf("%u", *v);
+}
+
+void printwire_u64(const u64 *v)
+{
+	printf("%"PRIu64, *v);
+}
+
+void printwire_u8_array(const u8 **cursor, size_t *plen, size_t len)
+{
+	printf("[");
+	while (len) {
+		u8 v = fromwire_u8(cursor, plen);
+		if (!*cursor)
+			return;
+		if (isprint(v))
+			printf("%c", v);
+		else
+			printf("\\x%02x", v);
+		len--;
+	}
+	printf("]\n");
+}
+
+#define PRINTWIRE_TYPE_TO_STRING(T, N)					\
+	void printwire_##N(const T *v)					\
+	{								\
+		const char *s = type_to_string(NULL, T, v);		\
+		printf("%s\n", s);					\
+		tal_free(s);						\
+	}
+
+#define PRINTWIRE_STRUCT_TYPE_TO_STRING(T) \
+	PRINTWIRE_TYPE_TO_STRING(struct T, T)
+
+PRINTWIRE_STRUCT_TYPE_TO_STRING(bitcoin_blkid);
+PRINTWIRE_STRUCT_TYPE_TO_STRING(bitcoin_txid);
+PRINTWIRE_STRUCT_TYPE_TO_STRING(channel_id);
+PRINTWIRE_STRUCT_TYPE_TO_STRING(preimage);
+PRINTWIRE_STRUCT_TYPE_TO_STRING(pubkey);
+PRINTWIRE_STRUCT_TYPE_TO_STRING(sha256);
+PRINTWIRE_STRUCT_TYPE_TO_STRING(short_channel_id);
+PRINTWIRE_TYPE_TO_STRING(secp256k1_ecdsa_signature, secp256k1_ecdsa_signature);

devtools/print_wire.h

@@ -0,0 +1,22 @@
+#ifndef LIGHTNING_DEVTOOLS_PRINT_WIRE_H
+#define LIGHTNING_DEVTOOLS_PRINT_WIRE_H
+#include <bitcoin/preimage.h>
+#include <bitcoin/tx.h>
+#include <wire/gen_peer_wire.h>
+
+void printwire_u8(const u8 *v);
+void printwire_u16(const u16 *v);
+void printwire_u32(const u32 *v);
+void printwire_u64(const u64 *v);
+void printwire_u8_array(const u8 **cursor, size_t *plen, size_t len);
+
+void printwire_bitcoin_blkid(const struct bitcoin_blkid *bitcoin_blkid);
+void printwire_bitcoin_txid(const struct bitcoin_txid *bitcoin_txid);
+void printwire_channel_id(const struct channel_id *channel_id);
+void printwire_preimage(const struct preimage *preimage);
+void printwire_pubkey(const struct pubkey *pubkey);
+void printwire_secp256k1_ecdsa_signature(const secp256k1_ecdsa_signature *);
+void printwire_sha256(const struct sha256 *sha256);
+void printwire_short_channel_id(const struct short_channel_id *short_channel_id);
+
+#endif /* LIGHTNING_DEVTOOLS_PRINT_WIRE_H */