From 40a391408c6edbabac4e408c1cdfdda64c0cd356 Mon Sep 17 00:00:00 2001
From: Yinan Zhang <zyn8950@gmail.com>
Date: Thu, 9 Jan 2020 16:50:09 -0800
Subject: [PATCH] Define constructor for buffered writer argument

---
 include/jemalloc/internal/buf_writer.h | 12 +++++++++++-
 src/jemalloc.c                         | 17 +++++++++--------
 src/prof_log.c                         | 17 +++++++++--------
 src/prof_recent.c                      |  5 +++--
 4 files changed, 32 insertions(+), 19 deletions(-)

diff --git a/include/jemalloc/internal/buf_writer.h b/include/jemalloc/internal/buf_writer.h
index 013bbf5d..1acda9a4 100644
--- a/include/jemalloc/internal/buf_writer.h
+++ b/include/jemalloc/internal/buf_writer.h
@@ -14,10 +14,20 @@ typedef struct {
 	void (*write_cb)(void *, const char *);
 	void *cbopaque;
 	char *buf;
-	size_t buf_size; /* must be one less than the capacity of buf array */
+	size_t buf_size;
 	size_t buf_end;
 } buf_write_arg_t;
 
+JEMALLOC_ALWAYS_INLINE void
+buf_write_init(buf_write_arg_t *arg, void (*write_cb)(void *, const char *),
+    void *cbopaque, char *buf, size_t buf_len) {
+	arg->write_cb = write_cb;
+	arg->cbopaque = cbopaque;
+	arg->buf = buf;
+	arg->buf_size = buf_len - 1; /* Accommodating '\0' at the end. */
+	arg->buf_end = 0;
+}
+
 void buf_write_flush(buf_write_arg_t *arg);
 void buf_write_cb(void *buf_write_arg, const char *s);
 
diff --git a/src/jemalloc.c b/src/jemalloc.c
index e54c49b0..5503fd00 100644
--- a/src/jemalloc.c
+++ b/src/jemalloc.c
@@ -3694,14 +3694,15 @@ je_malloc_stats_print(void (*write_cb)(void *, const char *), void *cbopaque,
 	if (config_debug) {
 		stats_print(write_cb, cbopaque, opts);
 	} else {
-		char *stats_print_buf = (char *)iallocztm(tsdn,
-		    STATS_PRINT_BUFSIZE, sz_size2index(STATS_PRINT_BUFSIZE),
-		    false, NULL, true, arena_get(TSDN_NULL, 0, true), true);
-		buf_write_arg_t stats_print_buf_arg = {write_cb, cbopaque,
-		    stats_print_buf, STATS_PRINT_BUFSIZE - 1, 0};
-		stats_print(buf_write_cb, &stats_print_buf_arg, opts);
-		buf_write_flush(&stats_print_buf_arg);
-		idalloctm(tsdn, stats_print_buf, NULL, NULL, true, true);
+		char *buf = (char *)iallocztm(tsdn, STATS_PRINT_BUFSIZE,
+		    sz_size2index(STATS_PRINT_BUFSIZE), false, NULL, true,
+		    arena_get(TSDN_NULL, 0, true), true);
+		buf_write_arg_t buf_arg;
+		buf_write_init(&buf_arg, write_cb, cbopaque, buf,
+		    STATS_PRINT_BUFSIZE);
+		stats_print(buf_write_cb, &buf_arg, opts);
+		buf_write_flush(&buf_arg);
+		idalloctm(tsdn, buf, NULL, NULL, true, true);
 	}
 
 	check_entry_exit_locking(tsdn);
diff --git a/src/prof_log.c b/src/prof_log.c
index d0b798de..9495cf7a 100644
--- a/src/prof_log.c
+++ b/src/prof_log.c
@@ -629,15 +629,16 @@ prof_log_stop(tsdn_t *tsdn) {
 	struct prof_emitter_cb_arg_s arg;
 	arg.fd = fd;
 
-	char *prof_log_stop_buf = (char *)iallocztm(tsdn,
-	    PROF_LOG_STOP_BUFSIZE, sz_size2index(PROF_LOG_STOP_BUFSIZE),
-	    false, NULL, true, arena_get(TSDN_NULL, 0, true), true);
-	buf_write_arg_t prof_log_stop_buf_arg = {prof_emitter_write_cb, &arg,
-	    prof_log_stop_buf, PROF_LOG_STOP_BUFSIZE - 1, 0};
+	char *buf = (char *)iallocztm(tsdn, PROF_LOG_STOP_BUFSIZE,
+	    sz_size2index(PROF_LOG_STOP_BUFSIZE), false, NULL, true,
+	    arena_get(TSDN_NULL, 0, true), true);
+	buf_write_arg_t buf_arg;
+	buf_write_init(&buf_arg, prof_emitter_write_cb, &arg, buf,
+	    PROF_LOG_STOP_BUFSIZE);
 
 	/* Emit to json. */
 	emitter_init(&emitter, emitter_output_json_compact, buf_write_cb,
-	    &prof_log_stop_buf_arg);
+	    &buf_arg);
 
 	emitter_begin(&emitter);
 	prof_log_emit_metadata(&emitter);
@@ -646,8 +647,8 @@ prof_log_stop(tsdn_t *tsdn) {
 	prof_log_emit_allocs(tsd, &emitter);
 	emitter_end(&emitter);
 
-	buf_write_flush(&prof_log_stop_buf_arg);
-	idalloctm(tsdn, prof_log_stop_buf, NULL, NULL, true, true);
+	buf_write_flush(&buf_arg);
+	idalloctm(tsdn, buf, NULL, NULL, true, true);
 
 	/* Reset global state. */
 	if (log_tables_initialized) {
diff --git a/src/prof_recent.c b/src/prof_recent.c
index a1f71ea1..ed4170e0 100644
--- a/src/prof_recent.c
+++ b/src/prof_recent.c
@@ -462,8 +462,9 @@ prof_recent_alloc_dump(tsd_t *tsd, void (*write_cb)(void *, const char *),
 	char *buf = (char *)iallocztm(tsd_tsdn(tsd), PROF_RECENT_PRINT_BUFSIZE,
 	    sz_size2index(PROF_RECENT_PRINT_BUFSIZE), false, NULL, true,
 	    arena_get(tsd_tsdn(tsd), 0, false), true);
-	buf_write_arg_t buf_arg = {write_cb, cbopaque, buf,
-	    PROF_RECENT_PRINT_BUFSIZE - 1, 0};
+	buf_write_arg_t buf_arg;
+	buf_write_init(&buf_arg, write_cb, cbopaque, buf,
+	    PROF_RECENT_PRINT_BUFSIZE);
 	emitter_t emitter;
 	emitter_init(&emitter, emitter_output_json_compact, buf_write_cb,
 	    &buf_arg);