vcs-svn: make buffer_read_binary API more convenient

buffer_read_binary is a thin wrapper around fread, but its signature
is wrong:

 - fread can fill an arbitrary in-memory buffer.  buffer_read_binary
   is limited to buffers whose size is representable by a 32-bit
   integer.
 - The result from fread is the number of bytes actually read.
   buffer_read_binary only reports the number of bytes read by
   incrementing sb->len by that amount and returns void.

Fix both: let buffer_read_binary accept a size_t instead of uint32_t
for the number of bytes to read and as a convenience return the number
of bytes actually read.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>

vcs-svn/line_buffer.c

@@ -91,10 +91,10 @@ char *buffer_read_line(struct line_buffer *buf)
 	return buf->line_buffer;
 }
 
-void buffer_read_binary(struct line_buffer *buf,
-				struct strbuf *sb, uint32_t size)
+size_t buffer_read_binary(struct line_buffer *buf,
+				struct strbuf *sb, size_t size)
 {
-	strbuf_fread(sb, size, buf->infile);
+	return strbuf_fread(sb, size, buf->infile);
 }
 
 off_t buffer_copy_bytes(struct line_buffer *buf, off_t nbytes)

vcs-svn/line_buffer.h

@@ -23,7 +23,7 @@ long buffer_tmpfile_prepare_to_read(struct line_buffer *buf);
 int buffer_ferror(struct line_buffer *buf);
 char *buffer_read_line(struct line_buffer *buf);
 int buffer_read_char(struct line_buffer *buf);
-void buffer_read_binary(struct line_buffer *buf, struct strbuf *sb, uint32_t len);
+size_t buffer_read_binary(struct line_buffer *buf, struct strbuf *sb, size_t len);
 /* Returns number of bytes read (not necessarily written). */
 off_t buffer_copy_bytes(struct line_buffer *buf, off_t len);
 off_t buffer_skip_bytes(struct line_buffer *buf, off_t len);