From 11c742e47c63f568782d9beee884c934ebbe143b Mon Sep 17 00:00:00 2001
From: Christos Zoulas <christos@zoulas.com>
Date: Fri, 3 Nov 2017 23:28:04 +0000
Subject: [PATCH] Add the end-of-file offset as a field.

---
 src/buffer.c | 6 ++++--
 src/file.h   | 3 ++-
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/buffer.c b/src/buffer.c
index a72b8ce6..38f18c4e 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -27,7 +27,7 @@
 #include "file.h"
 
 #ifndef	lint
-FILE_RCSID("@(#)$File: buffer.c,v 1.2 2017/11/03 00:18:55 christos Exp $")
+FILE_RCSID("@(#)$File: buffer.c,v 1.3 2017/11/03 23:28:04 christos Exp $")
 #endif	/* lint */
 
 #include "magic.h"
@@ -41,6 +41,7 @@ buffer_init(struct buffer *b, int fd, const void *data, size_t len)
 	b->fd = fd;
 	b->fbuf = data;
 	b->flen = len;
+	b->eoff = 0;
 	b->ebuf = NULL;
 	b->elen = 0;
 }
@@ -68,7 +69,8 @@ buffer_fill(const struct buffer *bb)
 	if ((b->ebuf = malloc(b->elen)) == NULL)
 		goto out;
 
-	if (pread(b->fd, b->ebuf, b->elen, st.st_size - b->elen) == -1) {
+	b->eoff = st.st_size - b->elen;
+	if (pread(b->fd, b->ebuf, b->elen, b->eoff) == -1) {
 		free(b->ebuf);
 		goto out;
 	}
diff --git a/src/file.h b/src/file.h
index 133c0e88..58cfc2f3 100644
--- a/src/file.h
+++ b/src/file.h
@@ -27,7 +27,7 @@
  */
 /*
  * file.h - definitions for file(1) program
- * @(#)$File: file.h,v 1.189 2017/11/03 14:28:54 christos Exp $
+ * @(#)$File: file.h,v 1.190 2017/11/03 23:28:04 christos Exp $
  */
 
 #ifndef __file_h__
@@ -149,6 +149,7 @@ struct buffer {
 	int fd;
 	const void *fbuf;
 	size_t flen;
+	off_t eoff;
 	void *ebuf;
 	size_t elen;
 };
-- 
2.40.0