daemon: add logging options.

Particularly logging to file.

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

Makefile

@@ -185,7 +185,7 @@ PROGRAMS := $(TEST_CLI_PROGRAMS) $(TEST_PROGRAMS)
 
 CWARNFLAGS := -Werror -Wall -Wundef -Wmissing-prototypes -Wmissing-declarations -Wstrict-prototypes -Wold-style-definition
 CDEBUGFLAGS := -g -fstack-protector
-CFLAGS := $(CWARNFLAGS) $(CDEBUGFLAGS) -I $(CCANDIR) -I secp256k1/include/ $(FEATURES)
+CFLAGS := $(CWARNFLAGS) $(CDEBUGFLAGS) -I $(CCANDIR) -I secp256k1/include/ -I . $(FEATURES)
 
 LDLIBS := -lcrypto -lprotobuf-c
 $(PROGRAMS): CFLAGS+=-I.

daemon/Makefile

@@ -24,4 +24,4 @@ check-source: $(DAEMON_HEADERS:%=check-hdr-include-order/%)
 check-daemon-makefile:
 	@if [ "`echo daemon/*.h`" != "$(DAEMON_HEADERS)" ]; then echo DAEMON_HEADERS incorrect; exit 1; fi
 
-daemon/lightningd: $(DAEMON_OBJS) $(CCAN_OBJS)
+daemon/lightningd: $(DAEMON_OBJS) $(CORE_OBJS) $(BITCOIN_OBJS) $(CCAN_OBJS) libsecp256k1.a

daemon/lightningd.c

@@ -1,8 +1,15 @@
 #include "lightningd.h"
 #include "log.h"
+#include <ccan/array_size/array_size.h>
+#include <ccan/err/err.h>
+#include <ccan/opt/opt.h>
+#include <ccan/tal/str/str.h>
 #include <ccan/tal/tal.h>
+#include <errno.h>
+#include <string.h>
 #include <sys/types.h>
 #include <unistd.h>
+#include <version.h>
 
 static struct lightningd_state *lightningd_state(void)
 {
@@ -15,11 +22,102 @@ static struct lightningd_state *lightningd_state(void)
 	return state;
 }
 
+static struct {
+	const char *name;
+	enum log_level level;
+} log_levels[] = {
+	{ "IO", LOG_IO },
+	{ "DEBUG", LOG_DBG },
+	{ "INFO", LOG_INFORM },
+	{ "UNUSUAL", LOG_UNUSUAL },
+	{ "BROKEN", LOG_BROKEN }
+};
+
+static char *arg_log_level(const char *arg, struct lightningd_state *state)
+{
+	size_t i;
+
+	for (i = 0; i < ARRAY_SIZE(log_levels); i++) {
+		if (strcasecmp(arg, log_levels[i].name) == 0) {
+			set_log_level(state->log_record, log_levels[i].level);
+			return NULL;
+		}
+	}
+	return tal_fmt(NULL, "unknown log level");
+}
+
+static char *arg_log_prefix(const char *arg, struct lightningd_state *state)
+{
+	set_log_prefix(state->base_log, arg);
+	return NULL;
+}
+
+static void log_to_file(const char *prefix,
+			enum log_level level,
+			bool continued,
+			const char *str,
+			struct lightningd_state *state)
+{
+	if (!continued) {
+		fprintf(state->logf, "%s %s\n", prefix, str);
+	} else {
+		fprintf(state->logf, "%s \t%s\n", prefix, str);
+	}
+}
+
+static char *arg_log_to_file(const char *arg, struct lightningd_state *state)
+{
+	state->logf = fopen(arg, "a");
+	if (!state->logf)
+		return tal_fmt(NULL, "Failed to open: %s", strerror(errno));
+	set_log_outfn(state->log_record, log_to_file, state);
+	return NULL;
+}
+
+/* Tal wrappers for opt. */
+static void *opt_allocfn(size_t size)
+{
+	return tal_alloc_(NULL, size, false, TAL_LABEL("opt_allocfn", ""));
+}
+
+static void *tal_reallocfn(void *ptr, size_t size)
+{
+	if (!ptr)
+		return opt_allocfn(size);
+	tal_resize_(&ptr, 1, size, false);
+	return ptr;
+}
+
+static void tal_freefn(void *ptr)
+{
+	tal_free(ptr);
+}
+
 int main(int argc, char *argv[])
 {
 	struct lightningd_state *state = lightningd_state();
 
+	err_set_progname(argv[0]);
+	opt_set_alloc(opt_allocfn, tal_reallocfn, tal_freefn);
+
+	opt_register_noarg("--help|-h", opt_usage_and_exit,
+			   "\n"
+			   "A bitcoin lightning daemon.",
+			   "Print this message.");
+	opt_register_arg("--log-level", arg_log_level, NULL, state,
+			 "log level (debug, info, unusual, broken)");
+	opt_register_arg("--log-prefix", arg_log_prefix, NULL, state,
+			 "log prefix");
+	opt_register_arg("--log-file=<file>", arg_log_to_file, NULL, state,
+			 "log to file instead of stdout");
+	opt_register_version();
+
+	opt_parse(&argc, argv, opt_log_stderr_exit);
+	if (argc != 1)
+		errx(1, "no arguments accepted");
+
 	log_info(state->base_log, "Hello world!");
 	tal_free(state);
+	opt_free_table();
 	return 0;
 }

daemon/lightningd.h

@@ -1,11 +1,13 @@
 #ifndef LIGHTNING_DAEMON_LIGHTNING_H
 #define LIGHTNING_DAEMON_LIGHTNING_H
 #include "config.h"
+#include <stdio.h>
 
 /* Here's where the global variables hide! */
 struct lightningd_state {
 	/* Where all our logging goes. */ 
 	struct log_record *log_record;
 	struct log *base_log;
+	FILE *logf;
 };
 #endif /* LIGHTNING_DAEMON_LIGHTNING_H */

daemon/log.c

@@ -20,7 +20,12 @@ struct log_entry {
 struct log_record {
 	size_t mem_used;
 	size_t max_mem;
-	enum log_level print;
+	void (*print)(const char *prefix,
+		      enum log_level level,
+		      bool continued,
+		      const char *str, void *arg);
+	void *print_arg;
+	enum log_level print_level;
 	struct timeabs init_time;
 
 	struct list_head log;
@@ -31,6 +36,18 @@ struct log {
 	const char *prefix;
 };
 
+static void log_default_print(const char *prefix,
+			      enum log_level level,
+			      bool continued,
+			      const char *str, void *arg)
+{
+	if (!continued) {
+		printf("%s %s\n", prefix, str);
+	} else {
+		printf("%s \t%s\n", prefix, str);
+	}
+}
+
 static size_t log_bufsize(const struct log_entry *e)
 {
 	if (e->level == LOG_IO)
@@ -76,7 +93,8 @@ struct log_record *new_log_record(const tal_t *ctx,
 	assert(max_mem > sizeof(struct log) * 2);
 	lr->mem_used = 0;
 	lr->max_mem = max_mem;
-	lr->print = printlevel;
+	lr->print = log_default_print;
+	lr->print_level = printlevel;
 	lr->init_time = time_now();
 	list_head_init(&lr->log);
 
@@ -101,7 +119,7 @@ new_log(const tal_t *ctx, struct log_record *record, const char *fmt, ...)
 
 void set_log_level(struct log_record *lr, enum log_level level)
 {
-	lr->print = level;
+	lr->print_level = level;
 }
 
 void set_log_prefix(struct log *log, const char *prefix)
@@ -110,6 +128,17 @@ void set_log_prefix(struct log *log, const char *prefix)
 	log->prefix = tal_strdup(log->lr, prefix);
 }
 
+void set_log_outfn_(struct log_record *lr,
+		    void (*print)(const char *prefix,
+				  enum log_level level,
+				  bool continued,
+				  const char *str, void *arg),
+		    void *arg)
+{
+	lr->print = print;
+	lr->print_arg = arg;
+}
+
 const char *log_prefix(const struct log *log)
 {
 	return log->prefix;
@@ -161,8 +190,9 @@ void logv(struct log *log, enum log_level level, const char *fmt, va_list ap)
 
 	l->log = tal_vfmt(l, fmt, ap);
 
-	if (level >= log->lr->print)
-		printf("%s %s\n", log->prefix, l->log);
+	if (level >= log->lr->print_level)
+		log->lr->print(log->prefix, level, false, l->log,
+			       log->lr->print_arg);
 
 	add_entry(log, l);
 }
@@ -176,12 +206,16 @@ void log_io(struct log *log, bool in, const void *data, size_t len)
 	l->log[0] = in;
 	memcpy(l->log + 1, data, len);
 
-	if (LOG_IO >= log->lr->print) {
-		char *hex = tal_arr(l, char, hex_str_size(len));
-		hex_encode(data, len, hex, hex_str_size(len));
-		printf("%s[%s] %s\n", log->prefix, in ? "IN" : "OUT", hex);
+	if (LOG_IO >= log->lr->print_level) {
+		const char *dir = in ? "[IN]" : "[OUT]";
+		char *hex = tal_arr(l, char, strlen(dir) + hex_str_size(len));
+		strcpy(hex, dir);
+		hex_encode(data, len, hex + strlen(dir), hex_str_size(len));
+		log->lr->print(log->prefix, LOG_IO, false, l->log,
+			       log->lr->print_arg);
 		tal_free(hex);
 	}
+
 	add_entry(log, l);
 	errno = save_errno;
 }
@@ -198,8 +232,9 @@ static void do_log_add(struct log *log, const char *fmt, va_list ap)
 	tal_append_vfmt(&l->log, fmt, ap);
 	add_entry(log, l);
 
-	if (l->level >= log->lr->print)
-		printf("%s \t%s\n", log->prefix, l->log + oldlen);
+	if (l->level >= log->lr->print_level)
+		log->lr->print(log->prefix, l->level, true, l->log + oldlen,
+			       log->lr->print_arg);
 }
 
 void log_(struct log *log, enum log_level level, const char *fmt, ...)

daemon/log.h

@@ -54,6 +54,20 @@ void log_add_enum_(struct log *log, const char *enumname, unsigned int val);
 void set_log_level(struct log_record *lr, enum log_level level);
 void set_log_prefix(struct log *log, const char *prefix);
 const char *log_prefix(const struct log *log);
+#define set_log_outfn(lr, print, arg)					\
+	set_log_outfn_((lr),						\
+		       typesafe_cb_preargs(void, void *, (print), (arg),\
+					   const char *,		\
+					   enum log_level,		\
+					   bool,			\
+					   const char *), (arg))
+
+void set_log_outfn_(struct log_record *lr,
+		    void (*print)(const char *prefix,
+				  enum log_level level,
+				  bool continued,
+				  const char *str, void *arg),
+		    void *arg);
 
 size_t log_max_mem(const struct log_record *lr);
 size_t log_used(const struct log_record *lr);