From bb499ce3ea390ce3bd9b334ab5817015247d4b47 Mon Sep 17 00:00:00 2001
From: Eric Biggers <ebiggers3@gmail.com>
Date: Wed, 14 Dec 2016 20:49:55 -0800
Subject: [PATCH 1/1] unix_apply.c: preallocate space for regular files

---
 configure.ac     | 2 +-
 src/unix_apply.c | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index 70b78681..46dd6f0f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -59,7 +59,7 @@ AM_CONDITIONAL([WINDOWS_NATIVE_BUILD], [test "$WINDOWS_NATIVE_BUILD" = "yes"])
 
 # Useful functions which we can do without.
 AC_CHECK_FUNCS([futimens utimensat flock mempcpy	\
-		openat fstatat readlinkat fdopendir])
+		openat fstatat readlinkat fdopendir posix_fallocate])
 
 # Header checks, most of which are only here to satisfy conditional includes
 # made by the libntfs-3g headers.
diff --git a/src/unix_apply.c b/src/unix_apply.c
index 672f39e7..e2ba76f9 100644
--- a/src/unix_apply.c
+++ b/src/unix_apply.c
@@ -585,6 +585,9 @@ retry_create:
 		return WIMLIB_ERR_OPEN;
 	}
 	filedes_init(&ctx->open_fds[ctx->num_open_fds++], fd);
+#ifdef HAVE_POSIX_FALLOCATE
+	posix_fallocate(fd, 0, blob->size);
+#endif
 	return unix_create_hardlinks(inode, first_dentry, first_path, ctx);
 }
 
-- 
2.43.0