Add quick-n-dirty debugging code to estimate memory usage.

Debugging code is not compiled by default, don't use it unless you're
just trying to measure something :)

Makefile

@@ -1,10 +1,16 @@
+-include make.conf
 OBJS := parser.o main.o redsocks.o log.o http-connect.o socks4.o socks5.o http-relay.o base.o base64.o md5.o http-auth.o utils.o redudp.o dnstc.o gen/version.o
+ifeq ($(DBG_BUILD),1)
+OBJS += debug.o
+endif
 SRCS := $(OBJS:.o=.c)
 CONF := config.h
 DEPS := .depend
 OUT := redsocks
 VERSION := 0.4
 
+# -levent_extra is required only for `http` and `debug`
+# -levent_core may be used for space reduction
 LIBS := -levent
 CFLAGS += -g -O2
 override CFLAGS += -std=c99 -D_XOPEN_SOURCE=600 -D_BSD_SOURCE -D_DEFAULT_SOURCE -Wall
@@ -29,6 +35,9 @@ $(CONF):
 		echo "/* Unknown system, only generic firewall code is compiled */" >$(CONF) \
 		;; \
 	esac
+ifeq ($(DBG_BUILD),1)
+	echo "#define DBG_BUILD 1" >>$(CONF)
+endif
 
 # Dependency on .git is useful to rebuild `version.c' after commit, but it breaks non-git builds.
 gen/version.c: *.c *.h gen/.build

debug.c

@@ -0,0 +1,159 @@
+/* redsocks - transparent TCP-to-proxy redirector
+ * Copyright (C) 2007-2011 Leonid Evdokimov <[email protected]>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License.  You may obtain a copy
+ * of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include "parser.h"
+#include "main.h"
+#include "log.h"
+#include "utils.h"
+#include <event2/http.h>
+#include <event2/buffer.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+typedef struct debug_instance_t {
+	int configured;
+	char* http_ip;
+	uint16_t http_port;
+	struct evhttp* http_server;
+} debug_instance;
+
+static debug_instance instance = {
+	.configured = 0,
+};
+
+static parser_entry debug_entries[] =
+{
+	{ .key = "http_ip", .type = pt_pchar },
+	{ .key = "http_port", .type = pt_uint16 },
+	{ }
+};
+
+static int debug_onenter(parser_section *section)
+{
+	if (instance.configured) {
+		parser_error(section->context, "only one instance of debug is valid");
+		return -1;
+	}
+	memset(&instance, 0, sizeof(instance));
+	for (parser_entry *entry = &section->entries[0]; entry->key; entry++)
+		entry->addr =
+			(strcmp(entry->key, "http_ip") == 0) ? (void*)&instance.http_ip:
+			(strcmp(entry->key, "http_port") == 0) ? (void*)&instance.http_port :
+			NULL;
+	return 0;
+}
+
+static int debug_onexit(parser_section *section)
+{
+	instance.configured = 1;
+	if (!instance.http_ip)
+		instance.http_ip = strdup("localhost");
+	return 0;
+}
+
+static parser_section debug_conf_section =
+{
+	.name    = "debug",
+	.entries = debug_entries,
+	.onenter = debug_onenter,
+	.onexit  = debug_onexit,
+};
+
+static void debug_meminfo_json(struct evhttp_request *req, void *arg)
+{
+	UNUSED(arg);
+
+	struct evbuffer* body = evbuffer_new();
+	evbuffer_add(body, "{", 1);
+
+	FILE* fd = fopen("/proc/vmstat", "r");
+	while (!feof(fd)) {
+		char buf[64];
+		size_t pages;
+		if (fscanf(fd, "%63s %zu", buf, &pages) == 2 && strncmp(buf, "nr_", 3) == 0) {
+			evbuffer_add_printf(body, "\"%s\": %zu, ", buf, pages);
+		}
+		for (int c = 0; c != EOF && c != '\n'; c = fgetc(fd))
+			;
+	}
+	fclose(fd);
+
+	size_t vmsize, rss, share, text, z, data;
+	fd = fopen("/proc/self/statm", "r");
+	if (fscanf(fd, "%zu %zu %zu %zu %zu %zu %zu", &vmsize, &rss, &share, &text, &z, &data, &z) == 7) {
+		evbuffer_add_printf(body,
+			"\"vmsize\": %zu, \"vmrss\": %zu, \"share\": %zu, \"text\": %zu, \"data\": %zu, ",
+			vmsize, rss, share, text, data);
+
+	}
+	fclose(fd);
+	evbuffer_add_printf(body, "\"getpagesize\": %d}", getpagesize());
+
+	evhttp_send_reply(req, HTTP_OK, NULL, body);
+	evbuffer_free(body);
+}
+
+static int debug_fini();
+
+static int debug_init(struct event_base* evbase)
+{
+	if (!instance.http_port)
+		return 0;
+
+	instance.http_server = evhttp_new(evbase);
+	if (!instance.http_server) {
+		log_errno(LOG_ERR, "evhttp_new()");
+		goto fail;
+	}
+
+	if (evhttp_bind_socket(instance.http_server, instance.http_ip, instance.http_port) != 0) {
+		log_errno(LOG_ERR, "evhttp_bind_socket()");
+		goto fail;
+	}
+
+	if (evhttp_set_cb(instance.http_server, "/debug/meminfo.json", debug_meminfo_json, NULL) != 0) {
+		log_errno(LOG_ERR, "evhttp_set_cb()");
+		goto fail;
+	}
+
+	return 0;
+
+fail:
+	debug_fini();
+	return -1;
+}
+
+static int debug_fini()
+{
+	if (instance.http_server) {
+		evhttp_free(instance.http_server);
+		instance.http_server = 0;
+	}
+	free(instance.http_ip);
+	memset(&instance, 0, sizeof(instance));
+	return 0;
+}
+
+app_subsys debug_subsys =
+{
+	.init = debug_init,
+	.fini = debug_fini,
+	.conf_section = &debug_conf_section,
+};
+
+/* vim:set tabstop=4 softtabstop=4 shiftwidth=4: */
+/* vim:set foldmethod=marker foldlevel=32 foldmarker={,}: */

main.c

@@ -26,14 +26,19 @@
 #include "main.h"
 #include "utils.h"
 #include "version.h"
+#include "config.h"
 
 extern app_subsys redsocks_subsys;
+extern app_subsys debug_subsys;
 extern app_subsys base_subsys;
 extern app_subsys redudp_subsys;
 extern app_subsys dnstc_subsys;
 
 app_subsys *subsystems[] = {
 	&redsocks_subsys,
+#ifdef DBG_BUILD
+	&debug_subsys,
+#endif
 	&base_subsys,
 	&redudp_subsys,
 	&dnstc_subsys,
@@ -118,12 +123,12 @@ int main(int argc, char **argv)
 	if (conftest)
 		return EXIT_SUCCESS;
 
-	event_init();
+	struct event_base* evbase = event_init();
 	memset(terminators, 0, sizeof(terminators));
 
 	FOREACH(ss, subsystems) {
 		if ((*ss)->init) {
-			error = (*ss)->init();
+			error = (*ss)->init(evbase);
 			if (error)
 				goto shutdown;
 		}
@@ -167,7 +172,7 @@ int main(int argc, char **argv)
 		if ((*ss)->fini)
 			(*ss)->fini();
 
-	event_base_free(NULL);
+	event_base_free(evbase);
 
 	return !error ? EXIT_SUCCESS : EXIT_FAILURE;
 }

main.h

@@ -3,8 +3,10 @@
 
 #include "parser.h"
 
+struct event_base;
+
 typedef struct app_subsys_t {
-	int (*init)();
+	int (*init)(struct event_base*);
 	int (*fini)();
 	parser_section* conf_section;
 } app_subsys;