[Emacs-diffs] trunk r113312: Fix openp errno handling.

[Paul Eggert]

------------------------------------------------------------
revno: 113312
revision-id: address@hidden
parent: address@hidden
committer: Paul Eggert <address@hidden>
branch nick: trunk
timestamp: Sun 2013-07-07 00:28:29 -0700
message:
  Fix openp errno handling.
  
  * callproc.c (Fcall_process): Preserve openp errno around close.
  * lread.c (openp): Set errno when returning -1, as some callers
  expect this.
modified:
  src/ChangeLog                  changelog-20091113204419-o5vbwnq5f7feedwu-1438
  src/callproc.c                 callproc.c-20091113204419-o5vbwnq5f7feedwu-248
  src/lread.c                    lread.c-20091113204419-o5vbwnq5f7feedwu-266

=== modified file 'src/ChangeLog'
--- a/src/ChangeLog     2013-07-06 17:58:41 +0000
+++ b/src/ChangeLog     2013-07-07 07:28:29 +0000
@@ -1,3 +1,10 @@
+2013-07-07  Paul Eggert  <address@hidden>
+
+       Fix openp errno handling.
+       * callproc.c (Fcall_process): Preserve openp errno around close.
+       * lread.c (openp): Set errno when returning -1, as some callers
+       expect this.
+
 2013-07-06  Jan Djärv  <address@hidden>
 
        * nsterm.m (sendEvent:): Handle NSAPP_DATA2_RUNFILEDIALOG.

=== modified file 'src/callproc.c'
--- a/src/callproc.c    2013-07-06 02:40:50 +0000
+++ b/src/callproc.c    2013-07-07 07:28:29 +0000
@@ -436,7 +436,9 @@
   }
   if (NILP (path))
     {
+      int openp_errno = errno;
       emacs_close (filefd);
+      errno = openp_errno;
       report_file_error ("Searching for program", Fcons (args[0], Qnil));
     }
 

=== modified file 'src/lread.c'
--- a/src/lread.c       2013-07-06 02:40:50 +0000
+++ b/src/lread.c       2013-07-07 07:28:29 +0000
@@ -1448,14 +1448,15 @@
 
 /* Search for a file whose name is STR, looking in directories
    in the Lisp list PATH, and trying suffixes from SUFFIX.
-   On success, returns a file descriptor.  On failure, returns -1.
+   On success, return a file descriptor (or 1 or -2 as described below).
+   On failure, return -1 and set errno.
 
    SUFFIXES is a list of strings containing possible suffixes.
    The empty suffix is automatically added if the list is empty.
 
    PREDICATE non-nil means don't open the files,
    just look for one that satisfies the predicate.  In this case,
-   returns 1 on success.  The predicate can be a lisp function or
+   return 1 on success.  The predicate can be a lisp function or
    an integer to pass to `access' (in which case file-name-handlers
    are ignored).
 
@@ -1467,7 +1468,8 @@
    but store the found remote file name in *STOREPTR.  */
 
 int
-openp (Lisp_Object path, Lisp_Object str, Lisp_Object suffixes, Lisp_Object 
*storeptr, Lisp_Object predicate)
+openp (Lisp_Object path, Lisp_Object str, Lisp_Object suffixes,
+       Lisp_Object *storeptr, Lisp_Object predicate)
 {
   ptrdiff_t fn_size = 100;
   char buf[100];
@@ -1478,6 +1480,7 @@
   struct gcpro gcpro1, gcpro2, gcpro3, gcpro4, gcpro5, gcpro6;
   Lisp_Object string, tail, encoded_fn;
   ptrdiff_t max_suffix_len = 0;
+  int last_errno = ENOENT;
 
   CHECK_STRING (str);
 
@@ -1547,14 +1550,22 @@
          if ((!NILP (handler) || !NILP (predicate)) && !NATNUMP (predicate))
             {
              bool exists;
+             last_errno = ENOENT;
              if (NILP (predicate))
                exists = !NILP (Ffile_readable_p (string));
              else
                {
                  Lisp_Object tmp = call1 (predicate, string);
-                 exists = !NILP (tmp)
-                   && (EQ (tmp, Qdir_ok)
-                       || NILP (Ffile_directory_p (string)));
+                 if (NILP (tmp))
+                   exists = 0;
+                 else if (EQ (tmp, Qdir_ok)
+                          || NILP (Ffile_directory_p (string)))
+                   exists = 1;
+                 else
+                   {
+                     exists = 0;
+                     last_errno = EISDIR;
+                   }
                }
 
              if (exists)
@@ -1576,21 +1587,36 @@
 
              /* Check that we can access or open it.  */
              if (NATNUMP (predicate))
-               fd = (((XFASTINT (predicate) & ~INT_MAX) == 0
-                      && (faccessat (AT_FDCWD, pfn, XFASTINT (predicate),
+               {
+                 fd = -1;
+                 if (INT_MAX < XFASTINT (predicate))
+                   last_errno = EINVAL;
+                 else if (faccessat (AT_FDCWD, pfn, XFASTINT (predicate),
                                      AT_EACCESS)
                           == 0)
-                      && ! file_directory_p (pfn))
-                     ? 1 : -1);
+                   {
+                     if (file_directory_p (pfn))
+                       last_errno = EISDIR;
+                     else
+                       fd = 1;
+                   }
+               }
              else
                {
-                 struct stat st;
                  fd = emacs_open (pfn, O_RDONLY, 0);
-                 if (fd >= 0
-                     && (fstat (fd, &st) != 0 || S_ISDIR (st.st_mode)))
+                 if (fd < 0)
+                   last_errno = errno;
+                 else
                    {
-                     emacs_close (fd);
-                     fd = -1;
+                     struct stat st;
+                     int err = (fstat (fd, &st) != 0 ? errno
+                                : S_ISDIR (st.st_mode) ? EISDIR : 0);
+                     if (err)
+                       {
+                         last_errno = err;
+                         emacs_close (fd);
+                         fd = -1;
+                       }
                    }
                }
 
@@ -1609,6 +1635,7 @@
     }
 
   UNGCPRO;
+  errno = last_errno;
   return -1;
 }