[nginx] Win32: reworked ngx_win32_rename_file() to check errors.

[Sergey Kandaurov]

details:   https://hg.nginx.org/nginx/rev/8880fe0b193c
branches:  
changeset: 8135:8880fe0b193c
user:      Maxim Dounin <mdounin at mdounin.ru>
date:      Thu Feb 23 20:49:50 2023 +0300
description:
Win32: reworked ngx_win32_rename_file() to check errors.

Previously, ngx_win32_rename_file() retried on all errors returned by
MoveFile() to a temporary name.  It only make sense, however, to retry
when the destination file already exists, similarly to the condition
when ngx_win32_rename_file() is called.  Retrying on other errors is
meaningless and might result in an infinite loop.

diffstat:

 src/os/win32/ngx_files.c |  12 ++++++++++--
 1 files changed, 10 insertions(+), 2 deletions(-)

diffs (31 lines):

diff -r 7d60e4584d9e -r 8880fe0b193c src/os/win32/ngx_files.c
--- a/src/os/win32/ngx_files.c	Thu Feb 23 20:49:47 2023 +0300
+++ b/src/os/win32/ngx_files.c	Thu Feb 23 20:49:50 2023 +0300
@@ -236,10 +236,16 @@ ngx_win32_rename_file(ngx_str_t *from, n
             break;
         }
 
-        collision = 1;
+        err = ngx_errno;
 
-        ngx_log_error(NGX_LOG_CRIT, log, ngx_errno,
+        if (err == NGX_EEXIST || err == NGX_EEXIST_FILE) {
+            collision = 1;
+            continue;
+        }
+
+        ngx_log_error(NGX_LOG_CRIT, log, err,
                       "MoveFile() \"%s\" to \"%s\" failed", to->data, name);
+        goto failed;
     }
 
     if (MoveFile((const char *) from->data, (const char *) to->data) == 0) {
@@ -254,6 +260,8 @@ ngx_win32_rename_file(ngx_str_t *from, n
                       "DeleteFile() \"%s\" failed", name);
     }
 
+failed:
+
     /* mutex_unlock() */
 
     ngx_free(name);