From: Paul Eggert <eggert@cs.ucla.edu>
Date: Wed, 16 Jul 2025 18:38:20 +0000 (-0700)
Subject: insert-file-contents small gap bug
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=120f850dfec233b5f8f22212325520d500c5dcc3;p=emacs.git

insert-file-contents small gap bug

Problem reported by Zhengyi Fu (Bug#79031).
* src/fileio.c (Finsert_file_contents): Do not read more than
requested, even when the gap is so small that we use a local buffer.

(cherry picked from commit e450a7802c544b7fa14fe064c62de1f9b7098e81)
---

diff --git a/src/fileio.c b/src/fileio.c
index 2c8855dba91..e33ac4afabf 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -4899,8 +4899,9 @@ by calling `format-decode', which see.  */)
 	else
 	  {
 	    buf = (char *) BEG_ADDR + PT_BYTE - BEG_BYTE + inserted;
-	    bufsize = min (min (gap_size, total - inserted), IO_BUFSIZE);
+	    bufsize = min (gap_size, IO_BUFSIZE);
 	  }
+	bufsize = min (bufsize, total - inserted);
 
 	if (!seekable && end_offset == TYPE_MAXIMUM (off_t))
 	  {