[Emacs-diffs] master 44ae136: Fix error messages when readdir cannot open a directory on MS-Windows

[Eli Zaretskii]

branch: master
commit 44ae1364908f91d877a6afa9bdd394e31fbd8311
Author: Eli Zaretskii <address@hidden>
Commit: Eli Zaretskii <address@hidden>

    Fix error messages when readdir cannot open a directory on MS-Windows
    
     src/dired.c (read_dirent): Accept an additional argument
     FIRST_ENTRY.  If readdir fails with ENOENT or EACCES the first
     time it is called, report the error as if it happened in
     open_directory.
     (directory_files_internal, file_name_completion): Adjust callers
     or read_dirent.
---
 src/ChangeLog |    9 +++++++++
 src/dired.c   |   25 ++++++++++++++++++++-----
 2 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/src/ChangeLog b/src/ChangeLog
index 67b6fa0..fc4258c 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,12 @@
+2015-01-30  Eli Zaretskii  <address@hidden>
+
+       * dired.c (read_dirent): Accept an additional argument
+       FIRST_ENTRY.  If readdir fails with ENOENT or EACCES the first
+       time it is called, report the error as if it happened in
+       open_directory.
+       (directory_files_internal, file_name_completion): Adjust callers
+       or read_dirent.
+
 2015-01-30  Paul Eggert  <address@hidden>
 
        Refactor calls to opendir for simplicity
diff --git a/src/dired.c b/src/dired.c
index 7982c1f..56d6de2 100644
--- a/src/dired.c
+++ b/src/dired.c
@@ -124,10 +124,11 @@ directory_files_internal_unwind (void *dh)
 
 /* Return the next directory entry from DIR; DIR's name is DIRNAME.
    If there are no more directory entries, return a null pointer.
-   Signal any unrecoverable errors.  */
+   Signal any unrecoverable errors.  FIRST_ENTRY true means this is
+   the first call after open_directory.  */
 
 static struct dirent *
-read_dirent (DIR *dir, Lisp_Object dirname)
+read_dirent (DIR *dir, Lisp_Object dirname, bool first_entry)
 {
   while (true)
     {
@@ -136,7 +137,16 @@ read_dirent (DIR *dir, Lisp_Object dirname)
       if (dp || errno == 0)
        return dp;
       if (! (errno == EAGAIN || errno == EINTR))
-       report_file_error ("Reading directory", dirname);
+       {
+         /* The MS-Windows implementation of 'opendir' doesn't
+            actually open a directory until the first call to
+            'readdir'.  If 'readdir' fails to open the directory, it
+            sets errno to ENOENT or EACCES, see w32.c.  */
+         if (first_entry && (errno == ENOENT || errno == EACCES))
+           report_file_error ("Opening directory", dirname);
+         else
+           report_file_error ("Reading directory", dirname);
+       }
       QUIT;
     }
 }
@@ -239,7 +249,8 @@ directory_files_internal (Lisp_Object directory, 
Lisp_Object full,
     needsep = 1;
 
   /* Loop reading directory entries.  */
-  for (struct dirent *dp; (dp = read_dirent (d, directory)); )
+  bool first_entry = true;
+  for (struct dirent *dp; (dp = read_dirent (d, directory, first_entry)); )
     {
       ptrdiff_t len = dirent_namelen (dp);
       Lisp_Object name = make_unibyte_string (dp->d_name, len);
@@ -247,6 +258,8 @@ directory_files_internal (Lisp_Object directory, 
Lisp_Object full,
       struct gcpro gcpro1, gcpro2;
       GCPRO2 (finalname, name);
 
+      first_entry = false;
+
       /* Note: DECODE_FILE can GC; it should protect its argument,
         though.  */
       name = DECODE_FILE (name);
@@ -486,11 +499,13 @@ file_name_completion (Lisp_Object file, Lisp_Object 
dirname, bool all_flag,
   record_unwind_protect_ptr (directory_files_internal_unwind, d);
 
   /* Loop reading directory entries.  */
-  for (struct dirent *dp; (dp = read_dirent (d, dirname)); )
+  bool first_entry = true;
+  for (struct dirent *dp; (dp = read_dirent (d, dirname, first_entry)); )
     {
       ptrdiff_t len = dirent_namelen (dp);
       bool canexclude = 0;
 
+      first_entry = false;
       QUIT;
       if (len < SCHARS (encoded_file)
          || (scmp (dp->d_name, SSDATA (encoded_file),