[nginx] Win32: additional error code NGX_EEXIST_FILE (ticket #910).

[Maxim Dounin]

details:   http://hg.nginx.org/nginx/rev/a5897d360977
branches:  
changeset: 6468:a5897d360977
user:      Maxim Dounin <mdounin at mdounin.ru>
date:      Tue Mar 29 09:51:46 2016 +0300
description:
Win32: additional error code NGX_EEXIST_FILE (ticket #910).

On Windows there are two possible error codes which correspond to
the EEXIST error code: ERROR_FILE_EXISTS used by CreateFile(CREATE_NEW),
and ERROR_ALREADY_EXISTS used by CreateDirectory().

MoveFile() seems to use both: ERROR_ALREADY_EXISTS when moving within
one filesystem, and ERROR_FILE_EXISTS when copying a file to a different
drive.

diffstat:

 src/core/ngx_file.c      |  4 ++--
 src/os/unix/ngx_errno.h  |  1 +
 src/os/win32/ngx_errno.h |  8 +++++++-
 3 files changed, 10 insertions(+), 3 deletions(-)

diffs (51 lines):

diff --git a/src/core/ngx_file.c b/src/core/ngx_file.c
--- a/src/core/ngx_file.c
+++ b/src/core/ngx_file.c
@@ -196,7 +196,7 @@ ngx_create_temp_file(ngx_file_t *file, n
 
         err = ngx_errno;
 
-        if (err == NGX_EEXIST) {
+        if (err == NGX_EEXIST_FILE) {
             n = (uint32_t) ngx_next_temp_number(1);
             continue;
         }
@@ -692,7 +692,7 @@ ngx_ext_rename_file(ngx_str_t *src, ngx_
 
 #if (NGX_WIN32)
 
-    if (err == NGX_EEXIST) {
+    if (err == NGX_EEXIST || err == NGX_EEXIST_FILE) {
         err = ngx_win32_rename_file(src, to, ext->log);
 
         if (err == 0) {
diff --git a/src/os/unix/ngx_errno.h b/src/os/unix/ngx_errno.h
--- a/src/os/unix/ngx_errno.h
+++ b/src/os/unix/ngx_errno.h
@@ -25,6 +25,7 @@ typedef int               ngx_err_t;
 #define NGX_EACCES        EACCES
 #define NGX_EBUSY         EBUSY
 #define NGX_EEXIST        EEXIST
+#define NGX_EEXIST_FILE   EEXIST
 #define NGX_EXDEV         EXDEV
 #define NGX_ENOTDIR       ENOTDIR
 #define NGX_EISDIR        EISDIR
diff --git a/src/os/win32/ngx_errno.h b/src/os/win32/ngx_errno.h
--- a/src/os/win32/ngx_errno.h
+++ b/src/os/win32/ngx_errno.h
@@ -25,8 +25,14 @@ typedef DWORD                      ngx_e
 #define NGX_ENOPATH                ERROR_PATH_NOT_FOUND
 #define NGX_ENOMEM                 ERROR_NOT_ENOUGH_MEMORY
 #define NGX_EACCES                 ERROR_ACCESS_DENIED
-/* it's seems that ERROR_FILE_EXISTS is not appropriate error code */
+/*
+ * there are two EEXIST error codes:
+ * ERROR_FILE_EXISTS used by CreateFile(CREATE_NEW),
+ * and ERROR_ALREADY_EXISTS used by CreateDirectory();
+ * MoveFile() uses both
+ */
 #define NGX_EEXIST                 ERROR_ALREADY_EXISTS
+#define NGX_EEXIST_FILE            ERROR_FILE_EXISTS
 /*
  * could not found cross volume directory move error code,
  * so use ERROR_WRONG_DISK as stub one