* callproc.c (Fcall_process_region): Fix minor race and tune.

(create_temp_file): New function, with the temp-file-creation part
of the old Fcall_process_region.  Use Fcopy_sequence to create the
temp file name, rather than alloca + build_string, for simplicity.
Don't bother to block input around the temp file creation;
shouldn't be needed.  Simplify use of mktemp.  Use
record_unwind_protect immediately after creating the temp file;
this closes an unlikely race where the temp file was not removed.
Use memcpy rather than an open-coded loop.
(Fcall_process_region): Use the new function.  If the input is
empty, redirect from /dev/null rather than from a newly created
empty temp file; this avoids unnecessary file system traffic.

1 files changed, 15 insertions, 0 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 329fa6ba670..cd6d188b686 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,18 @@
+2013-07-15  Paul Eggert  <eggert@cs.ucla.edu>
+
+        * callproc.c (Fcall_process_region): Fix minor race and tune.
+        (create_temp_file): New function, with the temp-file-creation part
+        of the old Fcall_process_region.  Use Fcopy_sequence to create the
+        temp file name, rather than alloca + build_string, for simplicity.
+        Don't bother to block input around the temp file creation;
+        shouldn't be needed.  Simplify use of mktemp.  Use
+        record_unwind_protect immediately after creating the temp file;
+        this closes an unlikely race where the temp file was not removed.
+        Use memcpy rather than an open-coded loop.
+        (Fcall_process_region): Use the new function.  If the input is
+        empty, redirect from /dev/null rather than from a newly created
+        empty temp file; this avoids unnecessary file system traffic.
+
 2013-07-14  Paul Eggert  <eggert@cs.ucla.edu>
 
         * filelock.c (create_lock_file) [!HAVE_MKOSTEMP && !HAVE_MKSTEMP]: