From 204234b9218a9967db5ab6da606846bed0e30133 Mon Sep 17 00:00:00 2001
From: Witold Filipczyk <witekfl@poczta.onet.pl>
Date: Tue, 26 Dec 2023 19:09:32 +0100
Subject: [PATCH] [memcount] libevent malloc, realloc, free replacement
 functions

---
 src/dialogs/info.c    |   3 ++
 src/main/select.c     |   5 ++
 src/util/memcount.cpp | 104 ++++++++++++++++++++++++++++++++++++++++++
 src/util/memcount.h   |   9 ++++
 4 files changed, 121 insertions(+)

diff --git a/src/dialogs/info.c b/src/dialogs/info.c
index ad3961aa3..1ad517350 100644
--- a/src/dialogs/info.c
+++ b/src/dialogs/info.c
@@ -281,6 +281,9 @@ get_resource_info(struct terminal *term, void *data)
 #ifdef CONFIG_LIBCURL
 	add_format_to_string(&info, "\nCurl: calls: %ld active: %ld, size: %ld", get_curl_total_allocs(), get_curl_active(), get_curl_size());
 #endif
+#ifdef CONFIG_LIBEVENT
+	add_format_to_string(&info, "\nLibevent: calls: %ld active: %ld, size: %ld", get_libevent_total_allocs(), get_libevent_active(), get_libevent_size());
+#endif
 #ifdef CONFIG_LIBSIXEL
 	add_format_to_string(&info, "\nSixel: calls: %ld active: %ld, size: %ld", get_sixel_total_allocs(), get_sixel_active(), get_sixel_size());
 #endif
diff --git a/src/main/select.c b/src/main/select.c
index caa2f600e..a0ce33dd4 100644
--- a/src/main/select.c
+++ b/src/main/select.c
@@ -877,6 +877,10 @@ enable_libevent(void)
 		return;
 #endif
 
+#if !defined(EVENT__DISABLE_MM_REPLACEMENT) && defined(CONFIG_DEBUG)
+	event_set_mem_functions(el_libevent_malloc, el_libevent_realloc, el_libevent_free);
+#endif
+
 #if defined(HAVE_EVENT_CONFIG_SET_FLAG)
 	{
 		struct event_config *cfg;
@@ -903,6 +907,7 @@ enable_libevent(void)
 #else
 	event_init();
 #endif
+
 	event_enabled = 1;
 
 	for (i = 0; i < w_max; i++)
diff --git a/src/util/memcount.cpp b/src/util/memcount.cpp
index 6fde64f16..10101136b 100644
--- a/src/util/memcount.cpp
+++ b/src/util/memcount.cpp
@@ -281,6 +281,109 @@ get_curl_active(void)
 }
 #endif
 
+#ifdef CONFIG_LIBEVENT
+
+static std::map<void *, uint64_t> el_libevent_allocs;
+static uint64_t el_libevent_total_allocs;
+static uint64_t el_libevent_size;
+
+/* call custom malloc() */
+void *
+el_libevent_malloc(
+    size_t              /* in */ size)          /* allocation size */
+{
+	static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
+	pthread_mutex_lock(&mutex);
+
+	void *res = mem_alloc(size);
+
+	if (res) {
+		el_libevent_allocs[res] = size;
+		el_libevent_total_allocs++;
+		el_libevent_size += size;
+	}
+	pthread_mutex_unlock(&mutex);
+
+	return res;
+}
+
+/* call custom realloc() */
+void *
+el_libevent_realloc(
+    void                /* in */ *p,          /* existing buffer to be re-allocated */
+    size_t              /* in */ n)          /* re-allocation size */
+{
+	if (!p) {
+		return el_libevent_malloc(n);
+	}
+	static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
+	pthread_mutex_lock(&mutex);
+
+	auto el = el_libevent_allocs.find(p);
+	size_t size = 0;
+	bool todelete = false;
+
+	if (el == el_libevent_allocs.end()) {
+		fprintf(stderr, "libevent %p not found\n", p);
+	} else {
+		size = el->second;
+		todelete = true;
+	}
+	void *ret = mem_realloc(p, n);
+
+	if (todelete) {
+		el_libevent_allocs.erase(el);
+	}
+	if (ret) {
+		el_libevent_allocs[ret] = n;
+		el_libevent_total_allocs++;
+		el_libevent_size += n - size;
+	}
+	pthread_mutex_unlock(&mutex);
+
+	return ret;
+}
+
+/* call custom free() */
+void
+el_libevent_free(
+    void                /* in */ *p)         /* existing buffer to be freed */
+{
+	static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
+	pthread_mutex_lock(&mutex);
+
+	auto el = el_libevent_allocs.find(p);
+
+	if (el == el_libevent_allocs.end()) {
+		fprintf(stderr, "libevent %p not found\n", p);
+		pthread_mutex_unlock(&mutex);
+		return;
+	}
+	el_libevent_size -= el->second;
+	el_libevent_allocs.erase(el);
+	mem_free(p);
+	pthread_mutex_unlock(&mutex);
+}
+
+uint64_t
+get_libevent_total_allocs(void)
+{
+	return el_libevent_total_allocs;
+}
+
+uint64_t
+get_libevent_size(void)
+{
+	return el_libevent_size;
+}
+
+uint64_t
+get_libevent_active(void)
+{
+	return el_libevent_allocs.size();
+}
+#endif
+
 
 #ifdef CONFIG_LIBSIXEL
 
@@ -395,6 +498,7 @@ get_sixel_active(void)
 }
 #endif
 
+
 #ifdef CONFIG_MUJS
 static std::map<void *, uint64_t> el_mujs_allocs;
 static uint64_t el_mujs_total_allocs;
diff --git a/src/util/memcount.h b/src/util/memcount.h
index b74c90ac0..d63eea54f 100644
--- a/src/util/memcount.h
+++ b/src/util/memcount.h
@@ -47,6 +47,15 @@ uint64_t get_curl_size(void);
 uint64_t get_curl_active(void);
 #endif
 
+#ifdef CONFIG_LIBEVENT
+void *el_libevent_malloc(size_t size);
+void *el_libevent_realloc(void *p, size_t n);
+void el_libevent_free(void *p);
+uint64_t get_libevent_total_allocs(void);
+uint64_t get_libevent_size(void);
+uint64_t get_libevent_active(void);
+#endif
+
 #ifdef CONFIG_LIBSIXEL
 void *el_sixel_malloc(size_t size);
 void *el_sixel_calloc(size_t nelm, size_t elsize);