Module Name: src
Committed By: sjg
Date: Tue Apr 24 20:26:58 UTC 2012
Modified Files:
src/usr.bin/make: buf.c buf.h var.c
Log Message:
Var* are generally very liberal with memory, with the expectation
that none of it persists for long.
This isn't always true - for example a long running .for loop.
Buf_DestroyCompact() is used by Var_Subst(), rather than Buf_Destroy().
If it looks like we can save BUF_COMPACT_LIMIT (128) or more bytes,
call realloc. This can reduce memory consumption by about 20%
Setting BUF_COMPACT_LIMIT to 0 dissables this.
To generate a diff of this commit:
cvs rdiff -u -r1.24 -r1.25 src/usr.bin/make/buf.c
cvs rdiff -u -r1.16 -r1.17 src/usr.bin/make/buf.h
cvs rdiff -u -r1.167 -r1.168 src/usr.bin/make/var.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/usr.bin/make/buf.c
diff -u src/usr.bin/make/buf.c:1.24 src/usr.bin/make/buf.c:1.25
--- src/usr.bin/make/buf.c:1.24 Sat Jan 17 13:29:37 2009
+++ src/usr.bin/make/buf.c Tue Apr 24 20:26:58 2012
@@ -1,4 +1,4 @@
-/* $NetBSD: buf.c,v 1.24 2009/01/17 13:29:37 dsl Exp $ */
+/* $NetBSD: buf.c,v 1.25 2012/04/24 20:26:58 sjg Exp $ */
/*
* Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -70,14 +70,14 @@
*/
#ifndef MAKE_NATIVE
-static char rcsid[] = "$NetBSD: buf.c,v 1.24 2009/01/17 13:29:37 dsl Exp $";
+static char rcsid[] = "$NetBSD: buf.c,v 1.25 2012/04/24 20:26:58 sjg Exp $";
#else
#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)buf.c 8.1 (Berkeley) 6/6/93";
#else
-__RCSID("$NetBSD: buf.c,v 1.24 2009/01/17 13:29:37 dsl Exp $");
+__RCSID("$NetBSD: buf.c,v 1.25 2012/04/24 20:26:58 sjg Exp $");
#endif
#endif /* not lint */
#endif
@@ -248,3 +248,44 @@ Buf_Destroy(Buffer *buf, Boolean freeDat
return data;
}
+
+
+/*-
+ *-----------------------------------------------------------------------
+ * Buf_DestroyCompact --
+ * Nuke a buffer and return its data.
+ *
+ * Input:
+ * buf Buffer to destroy
+ *
+ * Results:
+ * Data buffer
+ *
+ * Side Effects:
+ * If the buffer size is much greater than its content,
+ * a new buffer will be allocated and the old one freed.
+ *
+ *-----------------------------------------------------------------------
+ */
+#ifndef BUF_COMPACT_LIMIT
+# define BUF_COMPACT_LIMIT 128 /* worthwhile saving */
+#endif
+
+Byte *
+Buf_DestroyCompact(Buffer *buf)
+{
+#if BUF_COMPACT_LIMIT > 0
+ Byte *data;
+
+ if (buf->size - buf->count >= BUF_COMPACT_LIMIT) {
+ /* We trust realloc to be smart */
+ data = bmake_realloc(buf->buffer, buf->count + 1);
+ if (data) {
+ data[buf->count] = 0;
+ Buf_Destroy(buf, FALSE);
+ return data;
+ }
+ }
+#endif
+ return Buf_Destroy(buf, FALSE);
+}
Index: src/usr.bin/make/buf.h
diff -u src/usr.bin/make/buf.h:1.16 src/usr.bin/make/buf.h:1.17
--- src/usr.bin/make/buf.h:1.16 Sat Jan 17 13:55:42 2009
+++ src/usr.bin/make/buf.h Tue Apr 24 20:26:58 2012
@@ -1,4 +1,4 @@
-/* $NetBSD: buf.h,v 1.16 2009/01/17 13:55:42 dsl Exp $ */
+/* $NetBSD: buf.h,v 1.17 2012/04/24 20:26:58 sjg Exp $ */
/*
* Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -114,5 +114,6 @@ Byte *Buf_GetAll(Buffer *, int *);
void Buf_Empty(Buffer *);
void Buf_Init(Buffer *, int);
Byte *Buf_Destroy(Buffer *, Boolean);
+Byte *Buf_DestroyCompact(Buffer *);
#endif /* _BUF_H */
Index: src/usr.bin/make/var.c
diff -u src/usr.bin/make/var.c:1.167 src/usr.bin/make/var.c:1.168
--- src/usr.bin/make/var.c:1.167 Fri Jun 3 21:10:42 2011
+++ src/usr.bin/make/var.c Tue Apr 24 20:26:58 2012
@@ -1,4 +1,4 @@
-/* $NetBSD: var.c,v 1.167 2011/06/03 21:10:42 sjg Exp $ */
+/* $NetBSD: var.c,v 1.168 2012/04/24 20:26:58 sjg Exp $ */
/*
* Copyright (c) 1988, 1989, 1990, 1993
@@ -69,14 +69,14 @@
*/
#ifndef MAKE_NATIVE
-static char rcsid[] = "$NetBSD: var.c,v 1.167 2011/06/03 21:10:42 sjg Exp $";
+static char rcsid[] = "$NetBSD: var.c,v 1.168 2012/04/24 20:26:58 sjg Exp $";
#else
#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)var.c 8.3 (Berkeley) 3/19/94";
#else
-__RCSID("$NetBSD: var.c,v 1.167 2011/06/03 21:10:42 sjg Exp $");
+__RCSID("$NetBSD: var.c,v 1.168 2012/04/24 20:26:58 sjg Exp $");
#endif
#endif /* not lint */
#endif
@@ -4075,7 +4075,7 @@ Var_Subst(const char *var, const char *s
}
}
- return Buf_Destroy(&buf, FALSE);
+ return Buf_DestroyCompact(&buf);
}
/*-
