From: Andreas Gruenbacher <agruen@gnu.org>
Date: Fri, 6 Apr 2018 20:32:46 +0200
Subject: Minor cleanups in do_ed_script
Git-commit: 2a32bf09f5e9572da4be183bb0dbde8164351474
Patch-mainline: yes
References: bsc#1088420, savannah#53566, CVE-2018-1000156

* src/pch.c (do_ed_script): Minor cleanups.

Backporting notes: adjusted because we don't have commit ff1d3a67da1e
("Use gnulib execute module") so the context is very different.
---
 src/pch.c |   56 +++++++++++++++++++++++++++-----------------------------
 1 file changed, 27 insertions(+), 29 deletions(-)

--- a/src/pch.c
+++ b/src/pch.c
@@ -2395,6 +2395,8 @@ do_ed_script (char const *inname, char c
     char const *tmpname;
     int tmpfd;
     pid_t pid;
+    int exclusive = *outname_needs_removal ? 0 : O_EXCL;
+
 
     if (! dry_run && ! skip_rest_of_patch)
       {
@@ -2442,7 +2444,7 @@ do_ed_script (char const *inname, char c
 	    break;
 	}
     }
-    if (!tmpfp)
+    if (dry_run || skip_rest_of_patch)
       return;
     if (fwrite ("w\nq\n", sizeof (char), (size_t) 4, tmpfp) == 0
 	|| fflush (tmpfp) != 0)
@@ -2451,35 +2453,31 @@ do_ed_script (char const *inname, char c
     if (lseek (tmpfd, 0, SEEK_SET) == -1)
       pfatal ("Can't rewind to the beginning of file %s", quotearg (tmpname));
 
-    if (! dry_run && ! skip_rest_of_patch) {
-	int exclusive = *outname_needs_removal ? 0 : O_EXCL;
+    if (inerrno != ENOENT)
+      {
 	*outname_needs_removal = true;
-	if (inerrno != ENOENT)
-	  {
-	    *outname_needs_removal = true;
-	    copy_file (inname, outname, 0, exclusive, instat.st_mode, true);
-	  }
-	fflush (stdout);
-
-	pid = fork();
-	if (pid == -1)
-	  pfatal ("Can't fork");
-	else if (pid == 0)
-	  {
-	    dup2 (tmpfd, 0);
-	    assert (outname[0] != '!' && outname[0] != '-');
-	    execlp (editor_program, editor_program, "-", outname, (char  *) NULL);
-	    _exit (2);
-	  }
-	else
-	  {
-	    int wstatus;
-	    if (waitpid (pid, &wstatus, 0) == -1
-	        || ! WIFEXITED (wstatus)
-		|| WEXITSTATUS (wstatus) != 0)
-	      fatal ("%s FAILED", editor_program);
-	  }
-    }
+	copy_file (inname, outname, 0, exclusive, instat.st_mode, true);
+      }
+    fflush (stdout);
+
+    pid = fork();
+    if (pid == -1)
+      pfatal ("Can't fork");
+    else if (pid == 0)
+      {
+	dup2 (tmpfd, 0);
+	assert (outname[0] != '!' && outname[0] != '-');
+	execlp (editor_program, editor_program, "-", outname, (char  *) NULL);
+	_exit (2);
+      }
+    else
+      {
+	int wstatus;
+	if (waitpid (pid, &wstatus, 0) == -1
+	    || ! WIFEXITED (wstatus)
+	    || WEXITSTATUS (wstatus) != 0)
+	  fatal ("%s FAILED", editor_program);
+      }
 
     fclose (tmpfp);
     safe_unlink (tmpname);