[Emacs-diffs] trunk r113448: * filelock.c: Fix unlikely file descriptor leaks.

[Paul Eggert]

------------------------------------------------------------
revno: 113448
revision-id: address@hidden
parent: address@hidden
author: Paul Eggert  <address@hidden>
committer: Paul Eggert <address@hidden>
branch nick: trunk
timestamp: Thu 2013-07-18 03:24:26 -0700
message:
  * filelock.c: Fix unlikely file descriptor leaks.
  
  (get_boot_time_1): Rework to avoid using emacs_open.
  This doesn't actually fix a leak, but is better anyway.
  (read_lock_data): Use read, not emacs_read.
modified:
  src/ChangeLog                  changelog-20091113204419-o5vbwnq5f7feedwu-1438
  src/filelock.c                 filelock.c-20091113204419-o5vbwnq5f7feedwu-179

=== modified file 'src/ChangeLog'
--- a/src/ChangeLog     2013-07-18 09:55:00 +0000
+++ b/src/ChangeLog     2013-07-18 10:24:26 +0000
@@ -1,5 +1,10 @@
 2013-07-18  Paul Eggert  <address@hidden>
 
+       * filelock.c: Fix unlikely file descriptor leaks.
+       (get_boot_time_1): Rework to avoid using emacs_open.
+       This doesn't actually fix a leak, but is better anyway.
+       (read_lock_data): Use read, not emacs_read.
+
        * doc.c: Fix minor memory and file descriptor leaks.
        * doc.c (get_doc_string): Fix memory leak when doc file absent.
        (get_doc_string, Fsnarf_documentation):

=== modified file 'src/filelock.c'
--- a/src/filelock.c    2013-07-14 23:12:42 +0000
+++ b/src/filelock.c    2013-07-18 10:24:26 +0000
@@ -257,18 +257,14 @@
 get_boot_time_1 (const char *filename, bool newest)
 {
   struct utmp ut, *utp;
-  int desc;
 
   if (filename)
     {
       /* On some versions of IRIX, opening a nonexistent file name
         is likely to crash in the utmp routines.  */
-      desc = emacs_open (filename, O_RDONLY, 0);
-      if (desc < 0)
+      if (faccessat (AT_FDCWD, filename, R_OK, AT_EACCESS) != 0)
        return;
 
-      emacs_close (desc);
-
       utmpname (filename);
     }
 
@@ -512,7 +508,8 @@
       int fd = emacs_open (lfname, O_RDONLY | O_BINARY | O_NOFOLLOW, 0);
       if (0 <= fd)
        {
-         ptrdiff_t read_bytes = emacs_read (fd, lfinfo, MAX_LFINFO + 1);
+         /* Use read, not emacs_read, since FD isn't unwind-protected.  */
+         ptrdiff_t read_bytes = read (fd, lfinfo, MAX_LFINFO + 1);
          int read_errno = errno;
          if (emacs_close (fd) != 0)
            return -1;