From: Niels Provos <provos@gmail.com>
Date: Fri, 2 Jan 2009 18:18:30 +0000 (+0000)
Subject: malloc fd only if it is needed.
X-Git-Tag: release-2.0.1-alpha~193
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=172b657567777078296442f5363b9a1e764886b9;p=libevent

malloc fd only if it is needed.

svn:r982
---

diff --git a/evmap.c b/evmap.c
index 1a753bc3..183fcfad 100644
--- a/evmap.c
+++ b/evmap.c
@@ -56,14 +56,23 @@
 #include "evmap.h"
 #include "mm-internal.h"
 
-#define GET_SLOT(map, slot, type) (struct type *)((map)->entries[slot])
+#define GET_SLOT(x, map, slot, type)			\
+	(x) = (struct type *)((map)->entries[slot])
+#define GET_SLOT_AND_CTOR(x, map, slot, type, ctor)			\
+	do {								\
+		if ((map)->entries[slot] == NULL) {			\
+			assert(ctor != NULL);				\
+			(map)->entries[slot]=mm_malloc(sizeof(struct type)); \
+			assert((map)->entries[slot] != NULL);		\
+			(ctor)((struct type *)(map)->entries[slot]);	\
+		}							\
+		(x) = (struct type *)((map)->entries[slot]);		\
+	} while (0)							\
 
 static int
-evmap_make_space(
-	struct event_map *map, int slot, int msize, void (*ctor)(void *))
+evmap_make_space(struct event_map *map, int slot, int msize)
 {
 	if (map->nentries <= slot) {
-		int i;
 		int nentries = map->nentries ? map->nentries : 32;
 		void **tmp;
 
@@ -74,11 +83,8 @@ evmap_make_space(
 		if (tmp == NULL)
 			return (-1);
 		
-		for (i = map->nentries; i < nentries; ++i) {
-			tmp[i] = mm_malloc(msize);
-			assert(tmp[i] != NULL);
-			(*ctor)(tmp[i]);
-		}
+		memset(&tmp[map->nentries], 0,
+		    (nentries - map->nentries)  * sizeof(void *));
 
 		map->nentries = nentries;
 		map->entries = tmp;
@@ -94,8 +100,10 @@ evmap_clear(struct event_map *ctx)
 	ctx->nentries = 0;
 	if (ctx->entries != NULL) {
 		int i;
-		for (i = 0; i < ctx->nentries; ++i)
-			mm_free(ctx->entries[i]);
+		for (i = 0; i < ctx->nentries; ++i) {
+			if (ctx->entries[i] != NULL)
+				mm_free(ctx->entries[i]);
+		}
 		mm_free(ctx->entries);
 		ctx->entries = NULL;
 	}
@@ -130,11 +138,10 @@ evmap_io_add(struct event_base *base, int fd, struct event *ev)
 	short res = 0, old = 0;
 
 	if (fd >= io->nentries) {
-		if (evmap_make_space(io, fd,
-			sizeof(struct evmap_io), evmap_io_init) == -1)
+		if (evmap_make_space(io, fd, sizeof(struct evmap_io)) == -1)
 			return (-1);
 	}
-	ctx = GET_SLOT(io, fd, evmap_io);
+	GET_SLOT_AND_CTOR(ctx, io, fd, evmap_io, evmap_io_init);
 
 	nread = ctx->nread;
 	nwrite = ctx->nwrite;
@@ -181,7 +188,7 @@ evmap_io_del(struct event_base *base, int fd, struct event *ev)
 	if (fd >= io->nentries)
 		return (-1);
 	
-	ctx = GET_SLOT(io, fd, evmap_io);
+	GET_SLOT(ctx, io, fd, evmap_io);
 
 	nread = ctx->nread;
 	nwrite = ctx->nwrite;
@@ -222,7 +229,7 @@ evmap_io_active(struct event_base *base, int fd, short events)
 	struct event *ev;
 
 	assert(fd < io->nentries);
-	ctx = GET_SLOT(io, fd, evmap_io);
+	GET_SLOT(ctx, io, fd, evmap_io);
 
 	TAILQ_FOREACH(ev, &ctx->events, ev_io_next) {
 		if (ev->ev_events & events)
@@ -254,11 +261,10 @@ evmap_signal_add(struct event_base *base, int sig, struct event *ev)
 
 	if (sig >= map->nentries) {
 		if (evmap_make_space(
-			map, sig, sizeof(struct evmap_signal),
-			evmap_signal_init) == -1)
+			map, sig, sizeof(struct evmap_signal)) == -1)
 			return (-1);
 	}
-	ctx = GET_SLOT(map, sig, evmap_signal);
+	GET_SLOT_AND_CTOR(ctx, map, sig, evmap_signal, evmap_signal_init);
 
 	if (TAILQ_EMPTY(&ctx->events)) {
 		if (evsel->add(base, EVENT_SIGNAL(ev), 0, EV_SIGNAL) == -1)
@@ -280,7 +286,7 @@ evmap_signal_del(struct event_base *base, int sig, struct event *ev)
 	if (sig >= map->nentries)
 		return (-1);
 	
-	ctx = GET_SLOT(map, sig, evmap_signal);
+	GET_SLOT(ctx, map, sig, evmap_signal);
 
 	if (TAILQ_FIRST(&ctx->events) == TAILQ_LAST(&ctx->events, event_list)) {
 		if (evsel->del(base, EVENT_SIGNAL(ev), 0, EV_SIGNAL) == -1)
@@ -300,7 +306,7 @@ evmap_signal_active(struct event_base *base, int sig, int ncalls)
 	struct event *ev;
 
 	assert(sig < map->nentries);
-	ctx = GET_SLOT(map, sig, evmap_signal);
+	GET_SLOT(ctx, map, sig, evmap_signal);
 
 	TAILQ_FOREACH(ev, &ctx->events, ev_signal_next)
 		event_active(ev, EV_SIGNAL, ncalls);