build: avoid overriding system symbols for fopen functions

By introducing wrappers for them in the curlx namespace: `curlx_fopen()`, `curlx_fdopen()`, `curlx_fclose()`. The undefine/redefine/`(function)()` methods broke on systems implementing these functions as macros. E.g. AIX 32-bit's `fopen()`. Also: - rename `lib/fopen.*` to `lib/curl_fopen.*` (for `Curl_fopen()`) to make room for the newly added `curlx/fopen.h`. - curlx: move file-related functions from `multibyte.c` to `fopen.c`. - tests/server: stop using the curl-specific `fopen()` implementation on Windows. Unicode isn't used by runtests, and it isn't critical to run tests on longs path. It can be re-enabled if this becomes necessary, or if the wrapper receives a feature that's critical for test servers. Reported-by: Andrew Kirillov Bug: https://github.com/curl/curl/issues/18510#issuecomment-3274393640 Follow-up to bf7375ecc5 #18503 Follow-up to 9863599d69 #18502 Follow-up to 3bb5e58c10 #17827 Closes #18634
2026-01-18 17:21:26 +01:00 · 2025-09-14 15:34:18 +02:00
parent 10bac43b87
commit 20142f5d06
65 changed files with 568 additions and 484 deletions
--- a/.github/scripts/verify-examples.pl
+++ b/.github/scripts/verify-examples.pl
@@ -63,9 +63,9 @@ sub extract {
        elsif($syn == 1) {
            if(/^~~~/) {
                $syn++;
-                print O "/* !checksrc! disable UNUSEDIGNORE all */\n";
+                print O "/* !checksrc! disable BANNEDFUNC all */\n";  # for fopen()
                print O "/* !checksrc! disable COPYRIGHT all */\n";
-                print O "/* !checksrc! disable FOPENMODE all */\n";
+                print O "/* !checksrc! disable UNUSEDIGNORE all */\n";
                printf O "#line %d \"$f\"\n", $iline+1;
            }
        }
--- a/docs/examples/.checksrc
+++ b/docs/examples/.checksrc
@@ -1,3 +1,6 @@
+allowfunc fclose
+allowfunc fdopen
+allowfunc fopen
 allowfunc gmtime
 allowfunc localtime
 allowfunc socket
--- a/docs/internals/CHECKSRC.md
+++ b/docs/internals/CHECKSRC.md
@@ -76,7 +76,7 @@ warnings are:

 - `EXCLAMATIONSPACE`: space found after exclamations mark

- `FOPENMODE`: `fopen()` needs a macro for the mode string, use it
+- `FOPENMODE`: `curlx_fopen()` needs a macro for the mode string, use it

 - `INDENTATION`: detected a wrong start column for code. Note that this
   warning only checks some specific places and can certainly miss many bad
--- a/lib/Makefile.inc
+++ b/lib/Makefile.inc
@@ -26,6 +26,7 @@
 LIB_CURLX_CFILES = \
  curlx/base64.c   \
  curlx/dynbuf.c   \
+  curlx/fopen.c    \
  curlx/inet_ntop.c \
  curlx/inet_pton.c \
  curlx/multibyte.c \
@@ -43,6 +44,7 @@ LIB_CURLX_HFILES = \
  curlx/base64.h   \
  curlx/curlx.h    \
  curlx/dynbuf.h   \
+  curlx/fopen.h    \
  curlx/inet_ntop.h \
  curlx/inet_pton.h \
  curlx/multibyte.h \
@@ -157,6 +159,7 @@ LIB_CFILES =         \
  curl_des.c         \
  curl_endian.c      \
  curl_fnmatch.c     \
+  curl_fopen.c       \
  curl_get_line.c    \
  curl_gethostname.c \
  curl_gssapi.c      \
@@ -181,7 +184,6 @@ LIB_CFILES =         \
  fake_addrinfo.c    \
  file.c             \
  fileinfo.c         \
-  fopen.c            \
  formdata.c         \
  ftp.c              \
  ftplistparser.c    \
@@ -286,6 +288,7 @@ LIB_HFILES =         \
  curl_des.h         \
  curl_endian.h      \
  curl_fnmatch.h     \
+  curl_fopen.h       \
  curl_get_line.h    \
  curl_gethostname.h \
  curl_gssapi.h      \
@@ -320,7 +323,6 @@ LIB_HFILES =         \
  fake_addrinfo.h    \
  file.h             \
  fileinfo.h         \
-  fopen.h            \
  formdata.h         \
  ftp.h              \
  ftplistparser.h    \
--- a/lib/altsvc.c
+++ b/lib/altsvc.c
@@ -31,11 +31,11 @@
 #include <curl/curl.h>
 #include "urldata.h"
 #include "altsvc.h"
+#include "curl_fopen.h"
 #include "curl_get_line.h"
 #include "parsedate.h"
 #include "sendf.h"
 #include "curlx/warnless.h"
-#include "fopen.h"
 #include "rename.h"
 #include "strdup.h"
 #include "curlx/inet_pton.h"
@@ -227,7 +227,7 @@ static CURLcode altsvc_load(struct altsvcinfo *asi, const char *file)
  if(!asi->filename)
    return CURLE_OUT_OF_MEMORY;

-  fp = fopen(file, FOPEN_READTEXT);
+  fp = curlx_fopen(file, FOPEN_READTEXT);
  if(fp) {
    struct dynbuf buf;
    curlx_dyn_init(&buf, MAX_ALTSVC_LINE);
@@ -238,7 +238,7 @@ static CURLcode altsvc_load(struct altsvcinfo *asi, const char *file)
        altsvc_add(asi, lineptr);
    }
    curlx_dyn_free(&buf); /* free the line buffer */
-    fclose(fp);
+    curlx_fclose(fp);
  }
  return result;
 }
@@ -391,7 +391,7 @@ CURLcode Curl_altsvc_save(struct Curl_easy *data,
      if(result)
        break;
    }
-    fclose(out);
+    curlx_fclose(out);
    if(!result && tempstore && Curl_rename(tempstore, file))
      result = CURLE_WRITE_ERROR;

--- a/lib/cookie.c
+++ b/lib/cookie.c
@@ -80,11 +80,11 @@ Example set of cookies:
 #include "slist.h"
 #include "share.h"
 #include "strcase.h"
+#include "curl_fopen.h"
 #include "curl_get_line.h"
 #include "curl_memrchr.h"
 #include "parsedate.h"
 #include "rename.h"
-#include "fopen.h"
 #include "strdup.h"
 #include "llist.h"
 #include "curlx/strparse.h"
@@ -1195,7 +1195,7 @@ struct CookieInfo *Curl_cookie_init(struct Curl_easy *data,
      if(!strcmp(file, "-"))
        fp = stdin;
      else {
-        fp = fopen(file, "rb");
+        fp = curlx_fopen(file, "rb");
        if(!fp)
          infof(data, "WARNING: failed to open cookie file \"%s\"", file);
        else
@@ -1228,7 +1228,7 @@ struct CookieInfo *Curl_cookie_init(struct Curl_easy *data,
      remove_expired(ci);

      if(handle)
-        fclose(handle);
+        curlx_fclose(handle);
    }
    data->state.cookie_engine = TRUE;
  }
@@ -1583,7 +1583,7 @@ static CURLcode cookie_output(struct Curl_easy *data,
  }

  if(!use_stdout) {
-    fclose(out);
+    curlx_fclose(out);
    out = NULL;
    if(tempstore && Curl_rename(tempstore, filename)) {
      unlink(tempstore);
@@ -1602,7 +1602,7 @@ static CURLcode cookie_output(struct Curl_easy *data,

 error:
  if(out && !use_stdout)
-    fclose(out);
+    curlx_fclose(out);
  free(tempstore);
  return error;
 }
--- a/lib/curl_fopen.c
+++ b/lib/curl_fopen.c
@@ -33,7 +33,7 @@

 #include "urldata.h"
 #include "rand.h"
-#include "fopen.h"
+#include "curl_fopen.h"
 /* The last 3 #include files should be in this order */
 #include "curl_printf.h"
 #include "curl_memory.h"
@@ -102,7 +102,7 @@ CURLcode Curl_fopen(struct Curl_easy *data, const char *filename,
  char *dir = NULL;
  *tempname = NULL;

-  *fh = fopen(filename, FOPEN_WRITETEXT);
+  *fh = curlx_fopen(filename, FOPEN_WRITETEXT);
  if(!*fh)
    goto fail;
  if(
@@ -114,7 +114,7 @@ CURLcode Curl_fopen(struct Curl_easy *data, const char *filename,
     || !S_ISREG(sb.st_mode)) {
    return CURLE_OK;
  }
-  fclose(*fh);
+  curlx_fclose(*fh);
  *fh = NULL;

  result = Curl_rand_alnum(data, randbuf, sizeof(randbuf));
@@ -144,7 +144,7 @@ CURLcode Curl_fopen(struct Curl_easy *data, const char *filename,
  if(fd == -1)
    goto fail;

-  *fh = fdopen(fd, FOPEN_WRITETEXT);
+  *fh = curlx_fdopen(fd, FOPEN_WRITETEXT);
  if(!*fh)
    goto fail;

--- a/lib/curl_fopen.h
+++ b/lib/curl_fopen.h
@@ -24,6 +24,8 @@
 *
 ***************************************************************************/

+#include "curlx/fopen.h"
+
 CURLcode Curl_fopen(struct Curl_easy *data, const char *filename,
                    FILE **fh, char **tempname);

--- a/lib/curl_mem_undef.h
+++ b/lib/curl_mem_undef.h
@@ -33,16 +33,5 @@
 #undef Curl_tcsdup
 #endif

-#ifdef CURLDEBUG
-
-#undef fopen
-#ifdef CURL_FOPEN
-#define fopen(fname, mode) CURL_FOPEN(fname, mode)
-#endif
-#undef fdopen
-#undef fclose
-
-#endif /* CURLDEBUG */
-
 #undef HEADER_CURL_MEMORY_H
 #undef HEADER_CURL_MEMDEBUG_H
--- a/lib/curl_setup.h
+++ b/lib/curl_setup.h
@@ -509,11 +509,8 @@
 #  ifndef UNDER_CE
     int curlx_win32_stat(const char *path, struct_stat *buffer);
     int curlx_win32_open(const char *filename, int oflag, ...);
-     FILE *curlx_win32_fopen(const char *filename, const char *mode);
 #    define stat(fname, stp)           curlx_win32_stat(fname, stp)
 #    define open                       curlx_win32_open
-#    define CURL_FOPEN(fname, mode)    curlx_win32_fopen(fname, mode)
-#    define fopen(fname, mode)         CURL_FOPEN(fname, mode)
 #  endif
 #elif defined(__DJGPP__)
   /* Requires DJGPP 2.04 */
--- a/lib/curlx/curlx.h
+++ b/lib/curlx/curlx.h
@@ -64,6 +64,9 @@
 #include "dynbuf.h"
 /* The curlx_dyn_* functions */

+#include "fopen.h"
+/* The curlx_f* functions */
+
 #include "base64.h"
 #include "timeval.h"
 #include "timediff.h"
--- a/lib/curlx/fopen.c
+++ b/lib/curlx/fopen.c
@@ -0,0 +1,310 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ * SPDX-License-Identifier: curl
+ *
+ ***************************************************************************/
+
+/*
+ * This file is 'mem-include-scan' clean, which means its memory allocations
+ * are not tracked by the curl memory tracker memdebug, so they must not use
+ * `CURLDEBUG` macro replacements in memdebug.h for free, malloc, etc. To avoid
+ * these macro replacements, wrap the names in parentheses to call the original
+ * versions: `ptr = (malloc)(123)`, `(free)(ptr)`, etc.
+ */
+
+#include "../curl_setup.h"
+
+#if defined(_WIN32) && !defined(UNDER_CE)
+
+#include "fopen.h"
+#include "multibyte.h"
+
+/* declare GetFullPathNameW for mingw-w64 UWP builds targeting old windows */
+#if defined(CURL_WINDOWS_UWP) && defined(__MINGW32__) && \
+  (_WIN32_WINNT < _WIN32_WINNT_WIN10)
+WINBASEAPI DWORD WINAPI GetFullPathNameW(LPCWSTR, DWORD, LPWSTR, LPWSTR *);
+#endif
+
+/* Fix excessive paths (paths that exceed MAX_PATH length of 260).
+ *
+ * This is a helper function to fix paths that would exceed the MAX_PATH
+ * limitation check done by Windows APIs. It does so by normalizing the passed
+ * in filename or path 'in' to its full canonical path, and if that path is
+ * longer than MAX_PATH then setting 'out' to "\\?\" prefix + that full path.
+ *
+ * For example 'in' filename255chars in current directory C:\foo\bar is
+ * fixed as \\?\C:\foo\bar\filename255chars for 'out' which will tell Windows
+ * it is ok to access that filename even though the actual full path is longer
+ * than 260 chars.
+ *
+ * For non-Unicode builds this function may fail sometimes because only the
+ * Unicode versions of some Windows API functions can access paths longer than
+ * MAX_PATH, for example GetFullPathNameW which is used in this function. When
+ * the full path is then converted from Unicode to multibyte that fails if any
+ * directories in the path contain characters not in the current codepage.
+ */
+static bool fix_excessive_path(const TCHAR *in, TCHAR **out)
+{
+  size_t needed, count;
+  const wchar_t *in_w;
+  wchar_t *fbuf = NULL;
+
+  /* MS documented "approximate" limit for the maximum path length */
+  const size_t max_path_len = 32767;
+
+#ifndef _UNICODE
+  wchar_t *ibuf = NULL;
+  char *obuf = NULL;
+#endif
+
+  *out = NULL;
+
+  /* skip paths already normalized */
+  if(!_tcsncmp(in, _T("\\\\?\\"), 4))
+    goto cleanup;
+
+#ifndef _UNICODE
+  /* convert multibyte input to unicode */
+  needed = mbstowcs(NULL, in, 0);
+  if(needed == (size_t)-1 || needed >= max_path_len)
+    goto cleanup;
+  ++needed; /* for NUL */
+  ibuf = (malloc)(needed * sizeof(wchar_t));
+  if(!ibuf)
+    goto cleanup;
+  count = mbstowcs(ibuf, in, needed);
+  if(count == (size_t)-1 || count >= needed)
+    goto cleanup;
+  in_w = ibuf;
+#else
+  in_w = in;
+#endif
+
+  /* GetFullPathNameW returns the normalized full path in unicode. It converts
+     forward slashes to backslashes, processes .. to remove directory segments,
+     etc. Unlike GetFullPathNameA it can process paths that exceed MAX_PATH. */
+  needed = (size_t)GetFullPathNameW(in_w, 0, NULL, NULL);
+  if(!needed || needed > max_path_len)
+    goto cleanup;
+  /* skip paths that are not excessive and do not need modification */
+  if(needed <= MAX_PATH)
+    goto cleanup;
+  fbuf = (malloc)(needed * sizeof(wchar_t));
+  if(!fbuf)
+    goto cleanup;
+  count = (size_t)GetFullPathNameW(in_w, (DWORD)needed, fbuf, NULL);
+  if(!count || count >= needed)
+    goto cleanup;
+
+  /* prepend \\?\ or \\?\UNC\ to the excessively long path.
+   *
+   * c:\longpath            --->    \\?\c:\longpath
+   * \\.\c:\longpath        --->    \\?\c:\longpath
+   * \\?\c:\longpath        --->    \\?\c:\longpath  (unchanged)
+   * \\server\c$\longpath   --->    \\?\UNC\server\c$\longpath
+   *
+   * https://learn.microsoft.com/dotnet/standard/io/file-path-formats
+   */
+  if(!wcsncmp(fbuf, L"\\\\?\\", 4))
+    ; /* do nothing */
+  else if(!wcsncmp(fbuf, L"\\\\.\\", 4))
+    fbuf[2] = '?';
+  else if(!wcsncmp(fbuf, L"\\\\.", 3) || !wcsncmp(fbuf, L"\\\\?", 3)) {
+    /* Unexpected, not UNC. The formatting doc doesn't allow this AFAICT. */
+    goto cleanup;
+  }
+  else {
+    wchar_t *temp;
+
+    if(!wcsncmp(fbuf, L"\\\\", 2)) {
+      /* "\\?\UNC\" + full path without "\\" + null */
+      needed = 8 + (count - 2) + 1;
+      if(needed > max_path_len)
+        goto cleanup;
+
+      temp = (malloc)(needed * sizeof(wchar_t));
+      if(!temp)
+        goto cleanup;
+
+      wcsncpy(temp, L"\\\\?\\UNC\\", 8);
+      wcscpy(temp + 8, fbuf + 2);
+    }
+    else {
+      /* "\\?\" + full path + null */
+      needed = 4 + count + 1;
+      if(needed > max_path_len)
+        goto cleanup;
+
+      temp = (malloc)(needed * sizeof(wchar_t));
+      if(!temp)
+        goto cleanup;
+
+      wcsncpy(temp, L"\\\\?\\", 4);
+      wcscpy(temp + 4, fbuf);
+    }
+
+    (free)(fbuf);
+    fbuf = temp;
+  }
+
+#ifndef _UNICODE
+  /* convert unicode full path to multibyte output */
+  needed = wcstombs(NULL, fbuf, 0);
+  if(needed == (size_t)-1 || needed >= max_path_len)
+    goto cleanup;
+  ++needed; /* for NUL */
+  obuf = (malloc)(needed);
+  if(!obuf)
+    goto cleanup;
+  count = wcstombs(obuf, fbuf, needed);
+  if(count == (size_t)-1 || count >= needed)
+    goto cleanup;
+  *out = obuf;
+  obuf = NULL;
+#else
+  *out = fbuf;
+  fbuf = NULL;
+#endif
+
+cleanup:
+  (free)(fbuf);
+#ifndef _UNICODE
+  (free)(ibuf);
+  (free)(obuf);
+#endif
+  return *out ? true : false;
+}
+
+int curlx_win32_open(const char *filename, int oflag, ...)
+{
+  int pmode = 0;
+  int result = -1;
+  TCHAR *fixed = NULL;
+  const TCHAR *target = NULL;
+
+#ifdef _UNICODE
+  wchar_t *filename_w = curlx_convert_UTF8_to_wchar(filename);
+#endif
+
+  va_list param;
+  va_start(param, oflag);
+  if(oflag & O_CREAT)
+    pmode = va_arg(param, int);
+  va_end(param);
+
+#ifdef _UNICODE
+  if(filename_w) {
+    if(fix_excessive_path(filename_w, &fixed))
+      target = fixed;
+    else
+      target = filename_w;
+    result = _wopen(target, oflag, pmode);
+    curlx_unicodefree(filename_w);
+  }
+  else
+    /* !checksrc! disable ERRNOVAR 1 */
+    CURL_SETERRNO(EINVAL);
+#else
+  if(fix_excessive_path(filename, &fixed))
+    target = fixed;
+  else
+    target = filename;
+  result = _open(target, oflag, pmode);
+#endif
+
+  (free)(fixed);
+  return result;
+}
+
+FILE *curlx_win32_fopen(const char *filename, const char *mode)
+{
+  FILE *result = NULL;
+  TCHAR *fixed = NULL;
+  const TCHAR *target = NULL;
+
+#ifdef _UNICODE
+  wchar_t *filename_w = curlx_convert_UTF8_to_wchar(filename);
+  wchar_t *mode_w = curlx_convert_UTF8_to_wchar(mode);
+  if(filename_w && mode_w) {
+    if(fix_excessive_path(filename_w, &fixed))
+      target = fixed;
+    else
+      target = filename_w;
+    result = _wfopen(target, mode_w);
+  }
+  else
+    /* !checksrc! disable ERRNOVAR 1 */
+    CURL_SETERRNO(EINVAL);
+  curlx_unicodefree(filename_w);
+  curlx_unicodefree(mode_w);
+#else
+  if(fix_excessive_path(filename, &fixed))
+    target = fixed;
+  else
+    target = filename;
+  /* !checksrc! disable BANNEDFUNC 1 */
+  result = fopen(target, mode);
+#endif
+
+  (free)(fixed);
+  return result;
+}
+
+int curlx_win32_stat(const char *path, struct_stat *buffer)
+{
+  int result = -1;
+  TCHAR *fixed = NULL;
+  const TCHAR *target = NULL;
+
+#ifdef _UNICODE
+  wchar_t *path_w = curlx_convert_UTF8_to_wchar(path);
+  if(path_w) {
+    if(fix_excessive_path(path_w, &fixed))
+      target = fixed;
+    else
+      target = path_w;
+#ifndef USE_WIN32_LARGE_FILES
+    result = _wstat(target, buffer);
+#else
+    result = _wstati64(target, buffer);
+#endif
+    curlx_unicodefree(path_w);
+  }
+  else
+    /* !checksrc! disable ERRNOVAR 1 */
+    CURL_SETERRNO(EINVAL);
+#else
+  if(fix_excessive_path(path, &fixed))
+    target = fixed;
+  else
+    target = path;
+#ifndef USE_WIN32_LARGE_FILES
+  result = _stat(target, buffer);
+#else
+  result = _stati64(target, buffer);
+#endif
+#endif
+
+  (free)(fixed);
+  return result;
+}
+
+#endif /* _WIN32 && !UNDER_CE */
--- a/lib/curlx/fopen.h
+++ b/lib/curlx/fopen.h
@@ -0,0 +1,48 @@
+#ifndef HEADER_CURLX_FOPEN_H
+#define HEADER_CURLX_FOPEN_H
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ * SPDX-License-Identifier: curl
+ *
+ ***************************************************************************/
+
+#include "../curl_setup.h"
+
+#include "multibyte.h"
+
+#if defined(_WIN32) && !defined(UNDER_CE)
+FILE *curlx_win32_fopen(const char *filename, const char *mode);
+#define CURLX_FOPEN_LOW(fname, mode) curlx_win32_fopen(fname, mode)
+#else
+#define CURLX_FOPEN_LOW fopen
+#endif
+
+#ifdef CURLDEBUG
+#define curlx_fopen(file,mode) curl_dbg_fopen(file,mode,__LINE__,__FILE__)
+#define curlx_fdopen(file,mode) curl_dbg_fdopen(file,mode,__LINE__,__FILE__)
+#define curlx_fclose(file) curl_dbg_fclose(file,__LINE__,__FILE__)
+#else
+#define curlx_fopen CURLX_FOPEN_LOW
+#define curlx_fdopen fdopen
+#define curlx_fclose fclose
+#endif
+
+#endif /* HEADER_CURLX_FOPEN_H */
--- a/lib/curlx/multibyte.c
+++ b/lib/curlx/multibyte.c
@@ -84,277 +84,4 @@ char *curlx_convert_wchar_to_UTF8(const wchar_t *str_w)
  return str_utf8;
 }

-#ifndef UNDER_CE
-
-/* declare GetFullPathNameW for mingw-w64 UWP builds targeting old windows */
-#if defined(CURL_WINDOWS_UWP) && defined(__MINGW32__) && \
-  (_WIN32_WINNT < _WIN32_WINNT_WIN10)
-WINBASEAPI DWORD WINAPI GetFullPathNameW(LPCWSTR, DWORD, LPWSTR, LPWSTR *);
-#endif
-
-/* Fix excessive paths (paths that exceed MAX_PATH length of 260).
- *
- * This is a helper function to fix paths that would exceed the MAX_PATH
- * limitation check done by Windows APIs. It does so by normalizing the passed
- * in filename or path 'in' to its full canonical path, and if that path is
- * longer than MAX_PATH then setting 'out' to "\\?\" prefix + that full path.
- *
- * For example 'in' filename255chars in current directory C:\foo\bar is
- * fixed as \\?\C:\foo\bar\filename255chars for 'out' which will tell Windows
- * it is ok to access that filename even though the actual full path is longer
- * than 260 chars.
- *
- * For non-Unicode builds this function may fail sometimes because only the
- * Unicode versions of some Windows API functions can access paths longer than
- * MAX_PATH, for example GetFullPathNameW which is used in this function. When
- * the full path is then converted from Unicode to multibyte that fails if any
- * directories in the path contain characters not in the current codepage.
- */
-static bool fix_excessive_path(const TCHAR *in, TCHAR **out)
-{
-  size_t needed, count;
-  const wchar_t *in_w;
-  wchar_t *fbuf = NULL;
-
-  /* MS documented "approximate" limit for the maximum path length */
-  const size_t max_path_len = 32767;
-
-#ifndef _UNICODE
-  wchar_t *ibuf = NULL;
-  char *obuf = NULL;
-#endif
-
-  *out = NULL;
-
-  /* skip paths already normalized */
-  if(!_tcsncmp(in, _T("\\\\?\\"), 4))
-    goto cleanup;
-
-#ifndef _UNICODE
-  /* convert multibyte input to unicode */
-  needed = mbstowcs(NULL, in, 0);
-  if(needed == (size_t)-1 || needed >= max_path_len)
-    goto cleanup;
-  ++needed; /* for NUL */
-  ibuf = (malloc)(needed * sizeof(wchar_t));
-  if(!ibuf)
-    goto cleanup;
-  count = mbstowcs(ibuf, in, needed);
-  if(count == (size_t)-1 || count >= needed)
-    goto cleanup;
-  in_w = ibuf;
-#else
-  in_w = in;
-#endif
-
-  /* GetFullPathNameW returns the normalized full path in unicode. It converts
-     forward slashes to backslashes, processes .. to remove directory segments,
-     etc. Unlike GetFullPathNameA it can process paths that exceed MAX_PATH. */
-  needed = (size_t)GetFullPathNameW(in_w, 0, NULL, NULL);
-  if(!needed || needed > max_path_len)
-    goto cleanup;
-  /* skip paths that are not excessive and do not need modification */
-  if(needed <= MAX_PATH)
-    goto cleanup;
-  fbuf = (malloc)(needed * sizeof(wchar_t));
-  if(!fbuf)
-    goto cleanup;
-  count = (size_t)GetFullPathNameW(in_w, (DWORD)needed, fbuf, NULL);
-  if(!count || count >= needed)
-    goto cleanup;
-
-  /* prepend \\?\ or \\?\UNC\ to the excessively long path.
-   *
-   * c:\longpath            --->    \\?\c:\longpath
-   * \\.\c:\longpath        --->    \\?\c:\longpath
-   * \\?\c:\longpath        --->    \\?\c:\longpath  (unchanged)
-   * \\server\c$\longpath   --->    \\?\UNC\server\c$\longpath
-   *
-   * https://learn.microsoft.com/dotnet/standard/io/file-path-formats
-   */
-  if(!wcsncmp(fbuf, L"\\\\?\\", 4))
-    ; /* do nothing */
-  else if(!wcsncmp(fbuf, L"\\\\.\\", 4))
-    fbuf[2] = '?';
-  else if(!wcsncmp(fbuf, L"\\\\.", 3) || !wcsncmp(fbuf, L"\\\\?", 3)) {
-    /* Unexpected, not UNC. The formatting doc doesn't allow this AFAICT. */
-    goto cleanup;
-  }
-  else {
-    wchar_t *temp;
-
-    if(!wcsncmp(fbuf, L"\\\\", 2)) {
-      /* "\\?\UNC\" + full path without "\\" + null */
-      needed = 8 + (count - 2) + 1;
-      if(needed > max_path_len)
-        goto cleanup;
-
-      temp = (malloc)(needed * sizeof(wchar_t));
-      if(!temp)
-        goto cleanup;
-
-      wcsncpy(temp, L"\\\\?\\UNC\\", 8);
-      wcscpy(temp + 8, fbuf + 2);
-    }
-    else {
-      /* "\\?\" + full path + null */
-      needed = 4 + count + 1;
-      if(needed > max_path_len)
-        goto cleanup;
-
-      temp = (malloc)(needed * sizeof(wchar_t));
-      if(!temp)
-        goto cleanup;
-
-      wcsncpy(temp, L"\\\\?\\", 4);
-      wcscpy(temp + 4, fbuf);
-    }
-
-    (free)(fbuf);
-    fbuf = temp;
-  }
-
-#ifndef _UNICODE
-  /* convert unicode full path to multibyte output */
-  needed = wcstombs(NULL, fbuf, 0);
-  if(needed == (size_t)-1 || needed >= max_path_len)
-    goto cleanup;
-  ++needed; /* for NUL */
-  obuf = (malloc)(needed);
-  if(!obuf)
-    goto cleanup;
-  count = wcstombs(obuf, fbuf, needed);
-  if(count == (size_t)-1 || count >= needed)
-    goto cleanup;
-  *out = obuf;
-  obuf = NULL;
-#else
-  *out = fbuf;
-  fbuf = NULL;
-#endif
-
-cleanup:
-  (free)(fbuf);
-#ifndef _UNICODE
-  (free)(ibuf);
-  (free)(obuf);
-#endif
-  return *out ? true : false;
-}
-
-int curlx_win32_open(const char *filename, int oflag, ...)
-{
-  int pmode = 0;
-  int result = -1;
-  TCHAR *fixed = NULL;
-  const TCHAR *target = NULL;
-
-#ifdef _UNICODE
-  wchar_t *filename_w = curlx_convert_UTF8_to_wchar(filename);
-#endif
-
-  va_list param;
-  va_start(param, oflag);
-  if(oflag & O_CREAT)
-    pmode = va_arg(param, int);
-  va_end(param);
-
-#ifdef _UNICODE
-  if(filename_w) {
-    if(fix_excessive_path(filename_w, &fixed))
-      target = fixed;
-    else
-      target = filename_w;
-    result = _wopen(target, oflag, pmode);
-    curlx_unicodefree(filename_w);
-  }
-  else
-    /* !checksrc! disable ERRNOVAR 1 */
-    CURL_SETERRNO(EINVAL);
-#else
-  if(fix_excessive_path(filename, &fixed))
-    target = fixed;
-  else
-    target = filename;
-  result = _open(target, oflag, pmode);
-#endif
-
-  (free)(fixed);
-  return result;
-}
-
-FILE *curlx_win32_fopen(const char *filename, const char *mode)
-{
-  FILE *result = NULL;
-  TCHAR *fixed = NULL;
-  const TCHAR *target = NULL;
-
-#ifdef _UNICODE
-  wchar_t *filename_w = curlx_convert_UTF8_to_wchar(filename);
-  wchar_t *mode_w = curlx_convert_UTF8_to_wchar(mode);
-  if(filename_w && mode_w) {
-    if(fix_excessive_path(filename_w, &fixed))
-      target = fixed;
-    else
-      target = filename_w;
-    result = _wfopen(target, mode_w);
-  }
-  else
-    /* !checksrc! disable ERRNOVAR 1 */
-    CURL_SETERRNO(EINVAL);
-  curlx_unicodefree(filename_w);
-  curlx_unicodefree(mode_w);
-#else
-  if(fix_excessive_path(filename, &fixed))
-    target = fixed;
-  else
-    target = filename;
-  result = (fopen)(target, mode);
-#endif
-
-  (free)(fixed);
-  return result;
-}
-
-int curlx_win32_stat(const char *path, struct_stat *buffer)
-{
-  int result = -1;
-  TCHAR *fixed = NULL;
-  const TCHAR *target = NULL;
-
-#ifdef _UNICODE
-  wchar_t *path_w = curlx_convert_UTF8_to_wchar(path);
-  if(path_w) {
-    if(fix_excessive_path(path_w, &fixed))
-      target = fixed;
-    else
-      target = path_w;
-#ifndef USE_WIN32_LARGE_FILES
-    result = _wstat(target, buffer);
-#else
-    result = _wstati64(target, buffer);
-#endif
-    curlx_unicodefree(path_w);
-  }
-  else
-    /* !checksrc! disable ERRNOVAR 1 */
-    CURL_SETERRNO(EINVAL);
-#else
-  if(fix_excessive_path(path, &fixed))
-    target = fixed;
-  else
-    target = path;
-#ifndef USE_WIN32_LARGE_FILES
-  result = _stat(target, buffer);
-#else
-  result = _stati64(target, buffer);
-#endif
-#endif
-
-  (free)(fixed);
-  return result;
-}
-
-#endif /* UNDER_CE */
-
 #endif /* _WIN32 */
--- a/lib/hsts.c
+++ b/lib/hsts.c
@@ -32,10 +32,10 @@
 #include "urldata.h"
 #include "llist.h"
 #include "hsts.h"
+#include "curl_fopen.h"
 #include "curl_get_line.h"
 #include "sendf.h"
 #include "parsedate.h"
-#include "fopen.h"
 #include "rename.h"
 #include "share.h"
 #include "strdup.h"
@@ -379,7 +379,7 @@ CURLcode Curl_hsts_save(struct Curl_easy *data, struct hsts *h,
      if(result)
        break;
    }
-    fclose(out);
+    curlx_fclose(out);
    if(!result && tempstore && Curl_rename(tempstore, file))
      result = CURLE_WRITE_ERROR;

@@ -524,7 +524,7 @@ static CURLcode hsts_load(struct hsts *h, const char *file)
  if(!h->filename)
    return CURLE_OUT_OF_MEMORY;

-  fp = fopen(file, FOPEN_READTEXT);
+  fp = curlx_fopen(file, FOPEN_READTEXT);
  if(fp) {
    struct dynbuf buf;
    curlx_dyn_init(&buf, MAX_HSTS_LINE);
@@ -542,7 +542,7 @@ static CURLcode hsts_load(struct hsts *h, const char *file)
      hsts_add(h, lineptr);
    }
    curlx_dyn_free(&buf); /* free the line buffer */
-    fclose(fp);
+    curlx_fclose(fp);
  }
  return result;
 }
--- a/lib/memdebug.c
+++ b/lib/memdebug.c
@@ -29,6 +29,7 @@
 #include <curl/curl.h>

 #include "urldata.h"
+#include "curlx/fopen.h"  /* for CURLX_FOPEN_LOW() */

 /* The last 3 #include files should be in this order */
 #include "curl_printf.h"
@@ -68,7 +69,8 @@ static void curl_dbg_cleanup(void)
  if(curl_dbg_logfile &&
     curl_dbg_logfile != stderr &&
     curl_dbg_logfile != stdout) {
-    (fclose)(curl_dbg_logfile);
+    /* !checksrc! disable BANNEDFUNC 1 */
+    fclose(curl_dbg_logfile);
  }
  curl_dbg_logfile = NULL;
 }
@@ -78,11 +80,7 @@ void curl_dbg_memdebug(const char *logname)
 {
  if(!curl_dbg_logfile) {
    if(logname && *logname)
-#ifdef CURL_FOPEN
-      curl_dbg_logfile = CURL_FOPEN(logname, FOPEN_WRITETEXT);
-#else
-      curl_dbg_logfile = (fopen)(logname, FOPEN_WRITETEXT);
-#endif
+      curl_dbg_logfile = CURLX_FOPEN_LOW(logname, FOPEN_WRITETEXT);
    else
      curl_dbg_logfile = stderr;
 #ifdef MEMDEBUG_LOG_SYNC
@@ -424,13 +422,7 @@ ALLOC_FUNC
 FILE *curl_dbg_fopen(const char *file, const char *mode,
                     int line, const char *source)
 {
-  FILE *res;
-#ifdef CURL_FOPEN
-  res = CURL_FOPEN(file, mode);
-#else
-  res = (fopen)(file, mode);
-#endif
-
+  FILE *res = CURLX_FOPEN_LOW(file, mode);
  if(source)
    curl_dbg_log("FILE %s:%d fopen(\"%s\",\"%s\") = %p\n",
                source, line, file, mode, (void *)res);
@@ -442,7 +434,8 @@ ALLOC_FUNC
 FILE *curl_dbg_fdopen(int filedes, const char *mode,
                      int line, const char *source)
 {
-  FILE *res = (fdopen)(filedes, mode);
+  /* !checksrc! disable BANNEDFUNC 1 */
+  FILE *res = fdopen(filedes, mode);
  if(source)
    curl_dbg_log("FILE %s:%d fdopen(\"%d\",\"%s\") = %p\n",
                 source, line, filedes, mode, (void *)res);
@@ -459,7 +452,8 @@ int curl_dbg_fclose(FILE *file, int line, const char *source)
    curl_dbg_log("FILE %s:%d fclose(%p)\n",
                 source, line, (void *)file);

-  res = (fclose)(file);
+  /* !checksrc! disable BANNEDFUNC 1 */
+  res = fclose(file);

  return res;
 }
--- a/lib/memdebug.h
+++ b/lib/memdebug.h
@@ -52,12 +52,5 @@
 #endif
 #endif /* _WIN32 */

-#undef fopen
-#define fopen(file,mode) curl_dbg_fopen(file,mode,__LINE__,__FILE__)
-#undef fdopen
-#define fdopen(file,mode) curl_dbg_fdopen(file,mode,__LINE__,__FILE__)
-#undef fclose
-#define fclose(file) curl_dbg_fclose(file,__LINE__,__FILE__)
-
 #endif /* CURLDEBUG */
 #endif /* HEADER_CURL_MEMDEBUG_H */
--- a/lib/mime.c
+++ b/lib/mime.c
@@ -34,6 +34,7 @@ struct Curl_easy;
 #include "sendf.h"
 #include "transfer.h"
 #include "strdup.h"
+#include "curlx/fopen.h"
 #include "curlx/base64.h"

 #if !defined(CURL_DISABLE_MIME) && \
@@ -131,7 +132,7 @@ static const char aschex[] =

 #ifndef __VMS
 #define filesize(name, stat_data) (stat_data.st_size)
-#define fopen_read fopen
+#define fopen_read curlx_fopen

 #else

@@ -154,7 +155,7 @@ curl_off_t VmsRealFileSize(const char *name,
  int ret_stat;
  FILE * file;

-  file = fopen(name, FOPEN_READTEXT); /* VMS */
+  file = curlx_fopen(name, FOPEN_READTEXT); /* VMS */
  if(!file)
    return 0;

@@ -165,7 +166,7 @@ curl_off_t VmsRealFileSize(const char *name,
    if(ret_stat)
      count += ret_stat;
  }
-  fclose(file);
+  curlx_fclose(file);

  return count;
 }
@@ -210,10 +211,10 @@ static FILE * vmsfopenread(const char *file, const char *mode)
  case FAB$C_VAR:
  case FAB$C_VFC:
  case FAB$C_STMCR:
-    return fopen(file, FOPEN_READTEXT); /* VMS */
+    return curlx_fopen(file, FOPEN_READTEXT); /* VMS */
    break;
  default:
-    return fopen(file, FOPEN_READTEXT, "rfm=stmlf", "ctx=stm");
+    return curlx_fopen(file, FOPEN_READTEXT, "rfm=stmlf", "ctx=stm");
  }
 }

@@ -745,7 +746,7 @@ static void mime_file_free(void *ptr)
  curl_mimepart *part = (curl_mimepart *) ptr;

  if(part->fp) {
-    fclose(part->fp);
+    curlx_fclose(part->fp);
    part->fp = NULL;
  }
  Curl_safefree(part->data);
@@ -967,7 +968,7 @@ static size_t readback_part(curl_mimepart *part,
        mimesetstate(&part->state, MIMESTATE_END, NULL);
        /* Try sparing open file descriptors. */
        if(part->kind == MIMEKIND_FILE && part->fp) {
-          fclose(part->fp);
+          curlx_fclose(part->fp);
          part->fp = NULL;
        }
        FALLTHROUGH();
--- a/lib/netrc.c
+++ b/lib/netrc.c
@@ -39,6 +39,7 @@
 #include "netrc.h"
 #include "strcase.h"
 #include "curl_get_line.h"
+#include "curlx/fopen.h"
 #include "curlx/strparse.h"

 /* The last 3 #include files should be in this order */
@@ -76,7 +77,7 @@ enum found_state {
 static NETRCcode file2memory(const char *filename, struct dynbuf *filebuf)
 {
  NETRCcode ret = NETRC_FILE_MISSING; /* if it cannot open the file */
-  FILE *file = fopen(filename, FOPEN_READTEXT);
+  FILE *file = curlx_fopen(filename, FOPEN_READTEXT);
  struct dynbuf linebuf;
  curlx_dyn_init(&linebuf, MAX_NETRC_LINE);

@@ -99,7 +100,7 @@ static NETRCcode file2memory(const char *filename, struct dynbuf *filebuf)
 done:
  curlx_dyn_free(&linebuf);
  if(file)
-    fclose(file);
+    curlx_fclose(file);
  return ret;
 }

--- a/lib/vtls/gtls.c
+++ b/lib/vtls/gtls.c
@@ -54,6 +54,7 @@
 #include "../progress.h"
 #include "../select.h"
 #include "../strdup.h"
+#include "../curlx/fopen.h"
 #include "../curlx/warnless.h"
 #include "x509asn1.h"
 #include "../multiif.h"
@@ -211,7 +212,7 @@ static gnutls_datum_t load_file(const char *file)
  long filelen;
  void *ptr;

-  f = fopen(file, "rb");
+  f = curlx_fopen(file, "rb");
  if(!f)
    return loaded_file;
  if(fseek(f, 0, SEEK_END) != 0
@@ -227,7 +228,7 @@ static gnutls_datum_t load_file(const char *file)
  loaded_file.data = ptr;
  loaded_file.size = (unsigned int)filelen;
 out:
-  fclose(f);
+  curlx_fclose(f);
  return loaded_file;
 }

--- a/lib/vtls/keylog.c
+++ b/lib/vtls/keylog.c
@@ -33,6 +33,7 @@
 #include "keylog.h"
 #include <curl/curl.h>
 #include "../escape.h"
+#include "../curlx/fopen.h"

 /* The last #include files should be: */
 #include "../curl_memory.h"
@@ -49,7 +50,7 @@ Curl_tls_keylog_open(void)
  if(!keylog_file_fp) {
    keylog_file_name = curl_getenv("SSLKEYLOGFILE");
    if(keylog_file_name) {
-      keylog_file_fp = fopen(keylog_file_name, FOPEN_APPENDTEXT);
+      keylog_file_fp = curlx_fopen(keylog_file_name, FOPEN_APPENDTEXT);
      if(keylog_file_fp) {
 #ifdef _WIN32
        if(setvbuf(keylog_file_fp, NULL, _IONBF, 0))
@@ -57,7 +58,7 @@ Curl_tls_keylog_open(void)
        if(setvbuf(keylog_file_fp, NULL, _IOLBF, 4096))
 #endif
        {
-          fclose(keylog_file_fp);
+          curlx_fclose(keylog_file_fp);
          keylog_file_fp = NULL;
        }
      }
@@ -70,7 +71,7 @@ void
 Curl_tls_keylog_close(void)
 {
  if(keylog_file_fp) {
-    fclose(keylog_file_fp);
+    curlx_fclose(keylog_file_fp);
    keylog_file_fp = NULL;
  }
 }
--- a/lib/vtls/rustls.c
+++ b/lib/vtls/rustls.c
@@ -32,6 +32,7 @@

 #include <rustls.h>

+#include "../curlx/fopen.h"
 #include "../curlx/inet_pton.h"
 #include "../urldata.h"
 #include "../sendf.h"
@@ -397,7 +398,7 @@ static int
 read_file_into(const char *filename,
               struct dynbuf *out)
 {
-  FILE *f = fopen(filename, FOPEN_READTEXT);
+  FILE *f = curlx_fopen(filename, FOPEN_READTEXT);
  if(!f) {
    return 0;
  }
@@ -407,14 +408,14 @@ read_file_into(const char *filename,
    const size_t rr = fread(buf, 1, sizeof(buf), f);
    if(rr == 0 ||
       CURLE_OK != curlx_dyn_addn(out, buf, rr)) {
-      fclose(f);
+      curlx_fclose(f);
      return 0;
    }
    if(rr < sizeof(buf))
      break;
  }

-  return fclose(f) == 0;
+  return curlx_fclose(f) == 0;
 }

 static void
--- a/lib/vtls/schannel.c
+++ b/lib/vtls/schannel.c
@@ -47,6 +47,7 @@
 #include "../strdup.h"
 #include "../strerror.h"
 #include "../select.h" /* for the socket readiness */
+#include "../curlx/fopen.h"
 #include "../curlx/inet_pton.h" /* for IP addr SNI check */
 #include "../curlx/multibyte.h"
 #include "../curlx/warnless.h"
@@ -563,7 +564,7 @@ schannel_acquire_credential_handle(struct Curl_cfilter *cf,
                                 &cert_store_path, &cert_thumbprint_str);

      if(result && (data->set.ssl.primary.clientcert[0]!='\0'))
-        fInCert = fopen(data->set.ssl.primary.clientcert, "rb");
+        fInCert = curlx_fopen(data->set.ssl.primary.clientcert, "rb");

      if(result && !fInCert) {
        failf(data, "schannel: Failed to get certificate location"
@@ -611,7 +612,7 @@ schannel_acquire_credential_handle(struct Curl_cfilter *cf,
        if((!certdata) ||
           ((int) fread(certdata, certsize, 1, fInCert) != 1))
          continue_reading = FALSE;
-        fclose(fInCert);
+        curlx_fclose(fInCert);
        if(!continue_reading) {
          failf(data, "schannel: Failed to read cert file %s",
                data->set.ssl.primary.clientcert);
--- a/lib/vtls/vtls.c
+++ b/lib/vtls/vtls.c
@@ -68,6 +68,7 @@
 #include "../progress.h"
 #include "../share.h"
 #include "../multiif.h"
+#include "../curlx/fopen.h"
 #include "../curlx/timeval.h"
 #include "../curl_md5.h"
 #include "../curl_sha256.h"
@@ -803,7 +804,7 @@ CURLcode Curl_pin_peer_pubkey(struct Curl_easy *data,
    struct dynbuf buf;
    char unsigned *pem_ptr = NULL;
    size_t left;
-    FILE *fp = fopen(pinnedpubkey, "rb");
+    FILE *fp = curlx_fopen(pinnedpubkey, "rb");
    if(!fp)
      return result;

@@ -865,7 +866,7 @@ CURLcode Curl_pin_peer_pubkey(struct Curl_easy *data,
 end:
    curlx_dyn_free(&buf);
    Curl_safefree(pem_ptr);
-    fclose(fp);
+    curlx_fclose(fp);
  }

  return result;
--- a/scripts/checksrc.pl
+++ b/scripts/checksrc.pl
@@ -88,6 +88,9 @@ my %banfunc = (
    "send" => 1,
    "socket" => 1,
    "socketpair" => 1,
+    "fclose" => 1,
+    "fdopen" => 1,
+    "fopen" => 1,
    );

 my %warnings_extended = (
@@ -919,8 +922,8 @@ sub scanfile {
        }

        # scan for use of non-binary fopen without the macro
-        if($l =~ /^(.*\W)fopen\s*\([^,]*, *\"([^"]*)/) {
-            my $mode = $2;
+        if($l =~ /^(.*\W)(curlx_fopen|CURLX_FOPEN_LOW)\s*\([^,]*, *\"([^"]*)/) {
+            my $mode = $3;
            if($mode !~ /b/) {
                checkwarn("FOPENMODE",
                          $line, length($1), $file, $ol,
--- a/src/Makefile.inc
+++ b/src/Makefile.inc
@@ -36,6 +36,7 @@ CURLX_CFILES = \
  ../lib/curlx/base64.c \
  ../lib/curlx/multibyte.c \
  ../lib/curlx/dynbuf.c \
+  ../lib/curlx/fopen.c \
  ../lib/curlx/nonblock.c \
  ../lib/curlx/strparse.c \
  ../lib/curlx/timediff.c \
@@ -49,6 +50,7 @@ CURLX_HFILES = \
  ../lib/curlx/multibyte.h \
  ../lib/curl_setup.h \
  ../lib/curlx/dynbuf.h \
+  ../lib/curlx/fopen.h \
  ../lib/curlx/nonblock.h \
  ../lib/curlx/strparse.h \
  ../lib/curlx/timediff.h \
--- a/src/tool_cb_dbg.c
+++ b/src/tool_cb_dbg.c
@@ -124,7 +124,7 @@ int tool_debug_cb(CURL *handle, curl_infotype type,
      /* Ok, this is somewhat hackish but we do it undocumented for now */
      global->trace_stream = tool_stderr;
    else {
-      global->trace_stream = fopen(global->trace_dump, FOPEN_WRITETEXT);
+      global->trace_stream = curlx_fopen(global->trace_dump, FOPEN_WRITETEXT);
      global->trace_fopened = TRUE;
    }
  }
--- a/src/tool_cb_wrt.c
+++ b/src/tool_cb_wrt.c
@@ -55,7 +55,7 @@ bool tool_create_output_file(struct OutStruct *outs,
     (config->file_clobber_mode == CLOBBER_DEFAULT &&
      !outs->is_cd_filename)) {
    /* open file for writing */
-    file = fopen(fname, "wb");
+    file = curlx_fopen(fname, "wb");
  }
  else {
    int fd;
@@ -92,7 +92,7 @@ bool tool_create_output_file(struct OutStruct *outs,
       is not needed because we would have failed earlier, in the while loop
       and `fd` would now be -1 */
    if(fd != -1) {
-      file = fdopen(fd, "wb");
+      file = curlx_fdopen(fd, "wb");
      if(!file)
        close(fd);
    }
--- a/src/tool_cfgable.c
+++ b/src/tool_cfgable.c
@@ -258,7 +258,7 @@ static void free_globalconfig(void)
  tool_safefree(global->trace_dump);

  if(global->trace_fopened && global->trace_stream)
-    fclose(global->trace_stream);
+    curlx_fclose(global->trace_stream);
  global->trace_stream = NULL;

  tool_safefree(global->libcurl);
--- a/src/tool_easysrc.c
+++ b/src/tool_easysrc.c
@@ -178,7 +178,7 @@ void dumpeasysrc(void)
  FILE *out;
  bool fopened = FALSE;
  if(strcmp(o, "-")) {
-    out = fopen(o, FOPEN_WRITETEXT);
+    out = curlx_fopen(o, FOPEN_WRITETEXT);
    fopened = TRUE;
  }
  else
@@ -227,7 +227,7 @@ void dumpeasysrc(void)
      fprintf(out, "%s\n", c);

    if(fopened)
-      fclose(out);
+      curlx_fclose(out);
  }

  easysrc_free();
--- a/src/tool_formparse.c
+++ b/src/tool_formparse.c
@@ -563,14 +563,14 @@ static int get_param_part(char endchar,
            endpos--;
        sep = *p;
        *endpos = '\0';
-        fp = fopen(hdrfile, FOPEN_READTEXT);
+        fp = curlx_fopen(hdrfile, FOPEN_READTEXT);
        if(!fp)
          warnf("Cannot read from %s: %s", hdrfile,
                strerror(errno));
        else {
          int i = read_field_headers(hdrfile, fp, &headers);

-          fclose(fp);
+          curlx_fclose(fp);
          if(i) {
            curl_slist_free_all(headers);
            return -1;
--- a/src/tool_getparam.c
+++ b/src/tool_getparam.c
@@ -627,7 +627,7 @@ static ParameterError data_urlencode(const char *nextarg,
      CURLX_SET_BINMODE(stdin);
    }
    else {
-      file = fopen(p, "rb");
+      file = curlx_fopen(p, "rb");
      if(!file) {
        errorf("Failed to open %s", p);
        return PARAM_READ_ERROR;
@@ -637,7 +637,7 @@ static ParameterError data_urlencode(const char *nextarg,
    err = file2memory(&postdata, &size, file);

    if(file && (file != stdin))
-      fclose(file);
+      curlx_fclose(file);
    if(err)
      return err;
  }
@@ -899,7 +899,7 @@ static ParameterError set_data(cmdline_t cmd,
        CURLX_SET_BINMODE(stdin);
    }
    else {
-      file = fopen(nextarg, "rb");
+      file = curlx_fopen(nextarg, "rb");
      if(!file) {
        errorf("Failed to open %s", nextarg);
        return PARAM_READ_ERROR;
@@ -917,7 +917,7 @@ static ParameterError set_data(cmdline_t cmd,
    }

    if(file && (file != stdin))
-      fclose(file);
+      curlx_fclose(file);
    if(err)
      return err;

@@ -1094,7 +1094,7 @@ static ParameterError parse_url(struct OperationConfig *config,
    if(fromstdin)
      f = stdin;
    else
-      f = fopen(&nextarg[1], FOPEN_READTEXT);
+      f = curlx_fopen(&nextarg[1], FOPEN_READTEXT);
    if(f) {
      curlx_dyn_init(&line, 8092);
      while(my_get_line(f, &line, &error)) {
@@ -1104,7 +1104,7 @@ static ParameterError parse_url(struct OperationConfig *config,
          break;
      }
      if(!fromstdin)
-        fclose(f);
+        curlx_fclose(f);
      curlx_dyn_free(&line);
      if(error || err)
        return PARAM_READ_ERROR;
@@ -1206,7 +1206,7 @@ static ParameterError parse_ech(struct OperationConfig *config,
        file = stdin;
      }
      else {
-        file = fopen(nextarg, FOPEN_READTEXT);
+        file = curlx_fopen(nextarg, FOPEN_READTEXT);
      }
      if(!file) {
        warnf("Couldn't read file \"%s\" "
@@ -1216,7 +1216,7 @@ static ParameterError parse_ech(struct OperationConfig *config,
      }
      err = file2string(&tmpcfg, file);
      if(file != stdin)
-        fclose(file);
+        curlx_fclose(file);
      if(err)
        return err;
      config->ech_config = aprintf("ecl:%s",tmpcfg);
@@ -1242,7 +1242,7 @@ static ParameterError parse_header(struct OperationConfig *config,
  if(nextarg[0] == '@') {
    /* read many headers from a file or stdin */
    bool use_stdin = !strcmp(&nextarg[1], "-");
-    FILE *file = use_stdin ? stdin : fopen(&nextarg[1], FOPEN_READTEXT);
+    FILE *file = use_stdin ? stdin : curlx_fopen(&nextarg[1], FOPEN_READTEXT);
    if(!file) {
      errorf("Failed to open %s", &nextarg[1]);
      err = PARAM_READ_ERROR;
@@ -1263,7 +1263,7 @@ static ParameterError parse_header(struct OperationConfig *config,
        err = PARAM_READ_ERROR;
      curlx_dyn_free(&line);
      if(!use_stdin)
-        fclose(file);
+        curlx_fclose(file);
    }
  }
  else {
@@ -1536,7 +1536,7 @@ static ParameterError parse_writeout(struct OperationConfig *config,
    }
    else {
      fname = nextarg;
-      file = fopen(fname, FOPEN_READTEXT);
+      file = curlx_fopen(fname, FOPEN_READTEXT);
      if(!file) {
        errorf("Failed to open %s", fname);
        return PARAM_READ_ERROR;
@@ -1545,7 +1545,7 @@ static ParameterError parse_writeout(struct OperationConfig *config,
    tool_safefree(config->writeout);
    err = file2string(&config->writeout, file);
    if(file && (file != stdin))
-      fclose(file);
+      curlx_fclose(file);
    if(err)
      return err;
    if(!config->writeout)
--- a/src/tool_ipfs.c
+++ b/src/tool_ipfs.c
@@ -88,7 +88,7 @@ static char *ipfs_gateway(void)
  if(!gateway_composed_file_path)
    goto fail;

-  gateway_file = fopen(gateway_composed_file_path, FOPEN_READTEXT);
+  gateway_file = curlx_fopen(gateway_composed_file_path, FOPEN_READTEXT);
  tool_safefree(gateway_composed_file_path);

  if(gateway_file) {
@@ -103,7 +103,7 @@ static char *ipfs_gateway(void)
        goto fail;
    }

-    fclose(gateway_file);
+    curlx_fclose(gateway_file);
    gateway_file = NULL;

    if(curlx_dyn_len(&dyn))
@@ -121,7 +121,7 @@ static char *ipfs_gateway(void)
  }
 fail:
  if(gateway_file)
-    fclose(gateway_file);
+    curlx_fclose(gateway_file);
  tool_safefree(gateway);
  tool_safefree(ipfs_path);
  return NULL;
--- a/src/tool_operate.c
+++ b/src/tool_operate.c
@@ -164,7 +164,7 @@ static curl_off_t vms_realfilesize(const char *name,
  FILE * file;

  /* !checksrc! disable FOPENMODE 1 */
-  file = fopen(name, "r"); /* VMS */
+  file = curlx_fopen(name, "r"); /* VMS */
  if(!file) {
    return 0;
  }
@@ -175,7 +175,7 @@ static curl_off_t vms_realfilesize(const char *name,
    if(ret_stat)
      count += ret_stat;
  }
-  fclose(file);
+  curlx_fclose(file);

  return count;
 }
@@ -660,7 +660,7 @@ static CURLcode post_per_transfer(struct per_transfer *per,

  /* Close the outs file */
  if(outs->fopened && outs->stream) {
-    rc = fclose(outs->stream);
+    rc = curlx_fclose(outs->stream);
    if(!result && rc) {
      /* something went wrong in the writing process */
      result = CURLE_WRITE_ERROR;
@@ -696,13 +696,13 @@ skip:

  /* Close function-local opened file descriptors */
  if(per->heads.fopened && per->heads.stream)
-    fclose(per->heads.stream);
+    curlx_fclose(per->heads.stream);

  if(per->heads.alloc_filename)
    tool_safefree(per->heads.filename);

  if(per->etag_save.fopened && per->etag_save.stream)
-    fclose(per->etag_save.stream);
+    curlx_fclose(per->etag_save.stream);

  if(per->etag_save.alloc_filename)
    tool_safefree(per->etag_save.filename);
@@ -800,7 +800,7 @@ static CURLcode etag_compare(struct OperationConfig *config)
  ParameterError pe;

  /* open file for reading: */
-  FILE *file = fopen(config->etag_compare_file, FOPEN_READTEXT);
+  FILE *file = curlx_fopen(config->etag_compare_file, FOPEN_READTEXT);
  if(!file)
    warnf("Failed to open %s: %s", config->etag_compare_file,
          strerror(errno));
@@ -815,7 +815,7 @@ static CURLcode etag_compare(struct OperationConfig *config)

  if(!header) {
    if(file)
-      fclose(file);
+      curlx_fclose(file);
    errorf("Failed to allocate memory for custom etag header");
    return CURLE_OUT_OF_MEMORY;
  }
@@ -825,7 +825,7 @@ static CURLcode etag_compare(struct OperationConfig *config)
  tool_safefree(header);

  if(file)
-    fclose(file);
+    curlx_fclose(file);
  if(pe != PARAM_OK)
    result = CURLE_OUT_OF_MEMORY;
  return result;
@@ -843,7 +843,7 @@ static CURLcode etag_store(struct OperationConfig *config,

  /* open file for output: */
  if(strcmp(config->etag_save_file, "-")) {
-    FILE *newfile = fopen(config->etag_save_file, "ab");
+    FILE *newfile = curlx_fopen(config->etag_save_file, "ab");
    if(!newfile) {
      warnf("Failed creating file for saving etags: \"%s\". "
            "Skip this transfer", config->etag_save_file);
@@ -893,11 +893,11 @@ static CURLcode setup_headerfile(struct OperationConfig *config,
        return result;
    }
    if(!per->prev || per->prev->config != config) {
-      newfile = fopen(config->headerfile, "wb");
+      newfile = curlx_fopen(config->headerfile, "wb");
      if(newfile)
-        fclose(newfile);
+        curlx_fclose(newfile);
    }
-    newfile = fopen(config->headerfile, "ab");
+    newfile = curlx_fopen(config->headerfile, "ab");

    if(!newfile) {
      errorf("Failed to open %s", config->headerfile);
@@ -999,11 +999,11 @@ static CURLcode setup_outfile(struct OperationConfig *config,
 #ifdef __VMS
    /* open file for output, forcing VMS output format into stream
       mode which is needed for stat() call above to always work. */
-    FILE *file = fopen(outfile, "ab",
-                       "ctx=stm", "rfm=stmlf", "rat=cr", "mrs=0");
+    FILE *file = curlx_fopen(outfile, "ab",
+                           "ctx=stm", "rfm=stmlf", "rat=cr", "mrs=0");
 #else
    /* open file for output: */
-    FILE *file = fopen(per->outfile, "ab");
+    FILE *file = curlx_fopen(per->outfile, "ab");
 #endif
    if(!file) {
      errorf("cannot open '%s'", per->outfile);
@@ -1193,7 +1193,7 @@ static CURLcode single_transfer(struct OperationConfig *config,
    if(result) {
      curl_easy_cleanup(curl);
      if(etag_first.fopened)
-        fclose(etag_first.stream);
+        curlx_fclose(etag_first.stream);
      return result;
    }
    per->etag_save = etag_first; /* copy the whole struct */
@@ -2004,7 +2004,7 @@ static CURLcode cacertpaths(struct OperationConfig *config)
    char *cacert = NULL;
    FILE *cafile = tool_execpath("curl-ca-bundle.crt", &cacert);
    if(cafile) {
-      fclose(cafile);
+      curlx_fclose(cafile);
      config->cacert = strdup(cacert);
    }
 #elif !defined(CURL_WINDOWS_UWP) && !defined(UNDER_CE) && \
--- a/src/tool_parsecfg.c
+++ b/src/tool_parsecfg.c
@@ -93,7 +93,7 @@ int parseconfig(const char *filename)
    /* NULL means load .curlrc from homedir! */
    char *curlrc = findfile(".curlrc", CURLRC_DOTSCORE);
    if(curlrc) {
-      file = fopen(curlrc, FOPEN_READTEXT);
+      file = curlx_fopen(curlrc, FOPEN_READTEXT);
      if(!file) {
        free(curlrc);
        return 1;
@@ -115,7 +115,7 @@ int parseconfig(const char *filename)
  }
  else {
    if(strcmp(filename, "-"))
-      file = fopen(filename, FOPEN_READTEXT);
+      file = curlx_fopen(filename, FOPEN_READTEXT);
    else
      file = stdin;
  }
@@ -250,7 +250,7 @@ int parseconfig(const char *filename)
    curlx_dyn_free(&buf);
    curlx_dyn_free(&pbuf);
    if(file != stdin)
-      fclose(file);
+      curlx_fclose(file);
    if(fileerror)
      rc = 1;
  }
--- a/src/tool_ssls.c
+++ b/src/tool_ssls.c
@@ -66,7 +66,7 @@ CURLcode tool_ssls_load(struct OperationConfig *config,
  bool error = FALSE;

  curlx_dyn_init(&buf, MAX_SSLS_LINE);
-  fp = fopen(filename, FOPEN_READTEXT);
+  fp = curlx_fopen(filename, FOPEN_READTEXT);
  if(!fp) { /* ok if it does not exist */
    notef("SSL session file does not exist (yet?): %s", filename);
    goto out;
@@ -122,7 +122,7 @@ out:
  if(easy)
    curl_easy_cleanup(easy);
  if(fp)
-    fclose(fp);
+    curlx_fclose(fp);
  curlx_dyn_free(&buf);
  curl_free(shmac);
  curl_free(sdata);
@@ -190,7 +190,7 @@ CURLcode tool_ssls_save(struct OperationConfig *config,
  CURLcode r = CURLE_OK;

  ctx.exported = 0;
-  ctx.fp = fopen(filename, FOPEN_WRITETEXT);
+  ctx.fp = curlx_fopen(filename, FOPEN_WRITETEXT);
  if(!ctx.fp) {
    warnf("Warning: Failed to create SSL session file %s",
          filename);
@@ -207,6 +207,6 @@ out:
  if(easy)
    curl_easy_cleanup(easy);
  if(ctx.fp)
-    fclose(ctx.fp);
+    curlx_fclose(ctx.fp);
  return r;
 }
--- a/src/tool_stderr.c
+++ b/src/tool_stderr.c
@@ -50,12 +50,12 @@ void tool_set_stderr_file(const char *filename)

  /* precheck that filename is accessible to lessen the chance that the
     subsequent freopen will fail. */
-  fp = fopen(filename, FOPEN_WRITETEXT);
+  fp = curlx_fopen(filename, FOPEN_WRITETEXT);
  if(!fp) {
    warnf("Warning: Failed to open %s", filename);
    return;
  }
-  fclose(fp);
+  curlx_fclose(fp);

  /* freopen the actual stderr (stdio.h stderr) instead of tool_stderr since
     the latter may be set to stdout. */
--- a/src/tool_util.c
+++ b/src/tool_util.c
@@ -127,7 +127,7 @@ FILE *tool_execpath(const char *filename, char **pathp)
      if(strlen(filename) < remaining - 1) {
        curl_msnprintf(lastdirchar, remaining, "%s%s", DIR_CHAR, filename);
        *pathp = filebuffer;
-        return fopen(filebuffer, FOPEN_READTEXT);
+        return curlx_fopen(filebuffer, FOPEN_READTEXT);
      }
    }
  }
--- a/src/tool_writeout.c
+++ b/src/tool_writeout.c
@@ -772,13 +772,13 @@ void ourWriteOut(struct OperationConfig *config, struct per_transfer *per,
              break;
            case VAR_STDOUT:
              if(fclose_stream)
-                fclose(stream);
+                curlx_fclose(stream);
              fclose_stream = FALSE;
              stream = stdout;
              break;
            case VAR_STDERR:
              if(fclose_stream)
-                fclose(stream);
+                curlx_fclose(stream);
              fclose_stream = FALSE;
              stream = tool_stderr;
              break;
@@ -824,12 +824,12 @@ void ourWriteOut(struct OperationConfig *config, struct per_transfer *per,
              FILE *stream2;
              memcpy(fname, ptr, flen);
              fname[flen] = 0;
-              stream2 = fopen(fname, append ? FOPEN_APPENDTEXT :
-                              FOPEN_WRITETEXT);
+              stream2 = curlx_fopen(fname, append ? FOPEN_APPENDTEXT :
+                                    FOPEN_WRITETEXT);
              if(stream2) {
                /* only change if the open worked */
                if(fclose_stream)
-                  fclose(stream);
+                  curlx_fclose(stream);
                stream = stream2;
                fclose_stream = TRUE;
              }
@@ -872,6 +872,6 @@ void ourWriteOut(struct OperationConfig *config, struct per_transfer *per,
    }
  }
  if(fclose_stream)
-    fclose(stream);
+    curlx_fclose(stream);
  curlx_dyn_free(&name);
 }
--- a/src/var.c
+++ b/src/var.c
@@ -455,7 +455,7 @@ ParameterError setvariable(const char *input)
    if(use_stdin)
      file = stdin;
    else {
-      file = fopen(line, "rb");
+      file = curlx_fopen(line, "rb");
      if(!file) {
        errorf("Failed to open %s: %s", line, strerror(errno));
        err = PARAM_READ_ERROR;
@@ -469,7 +469,7 @@ ParameterError setvariable(const char *input)
    }
    curlx_dyn_free(&fname);
    if(!use_stdin && file)
-      fclose(file);
+      curlx_fclose(file);
    if(err)
      return err;
  }
--- a/tests/data/test1185
+++ b/tests/data/test1185
@@ -47,7 +47,7 @@ func_return() ;

 a = sprintf(buffer, "%s", moo);

-FILE *f = fopen("filename", "r");
+FILE *f = curlx_fopen("filename", "r");

 void startfunc(int a, int b) {
  func();
@@ -124,7 +124,7 @@ void startfunc(int a, int b) {
 a = sprintf(buffer, "%s", moo);
     ^
 ./%LOGDIR/code1185.c:32:11: warning: use of non-binary fopen without FOPEN_* macro: r (FOPENMODE)
- FILE *f = fopen("filename", "r");
+ FILE *f = curlx_fopen("filename", "r");
           ^
 ./%LOGDIR/code1185.c:34:30: warning: wrongly placed open brace (BRACEPOS)
 void startfunc(int a, int b) {
--- a/tests/libtest/Makefile.inc
+++ b/tests/libtest/Makefile.inc
@@ -34,6 +34,7 @@ UTILS_C = memptr.c testutil.c testtrace.c
 UTILS_H = testutil.h testtrace.h unitcheck.h

 CURLX_C = \
+  ../../lib/curlx/fopen.c \
  ../../lib/curlx/warnless.c \
  ../../lib/curlx/multibyte.c \
  ../../lib/curlx/timediff.c \
--- a/tests/libtest/cli_h2_serverpush.c
+++ b/tests/libtest/cli_h2_serverpush.c
@@ -30,7 +30,7 @@ static FILE *out_download;

 static int setup_h2_serverpush(CURL *hnd, const char *url)
 {
-  out_download = fopen("download_0.data", "wb");
+  out_download = curlx_fopen("download_0.data", "wb");
  if(!out_download)
    return 1;  /* failed */

@@ -72,7 +72,7 @@ static int server_push_callback(CURL *parent,
  curl_msnprintf(filename, sizeof(filename) - 1, "push%u", count++);

  /* here's a new stream, save it in a new file for each new push */
-  out_push = fopen(filename, "wb");
+  out_push = curlx_fopen(filename, "wb");
  if(!out_push) {
    /* if we cannot save it, deny it */
    curl_mfprintf(stderr, "Failed to create output file for push\n");
@@ -129,7 +129,7 @@ static CURLcode test_cli_h2_serverpush(const char *URL)

  easy = curl_easy_init();
  if(setup_h2_serverpush(easy, URL)) {
-    fclose(out_download);
+    curlx_fclose(out_download);
    curl_mfprintf(stderr, "failed\n");
    return (CURLcode)1;
  }
@@ -166,9 +166,9 @@ static CURLcode test_cli_h2_serverpush(const char *URL)

  curl_multi_cleanup(multi_handle);

-  fclose(out_download);
+  curlx_fclose(out_download);
  if(out_push)
-    fclose(out_push);
+    curlx_fclose(out_push);

  return CURLE_OK;
 }
--- a/tests/libtest/cli_hx_download.c
+++ b/tests/libtest/cli_hx_download.c
@@ -94,7 +94,7 @@ static size_t my_write_d_cb(char *buf, size_t nitems, size_t buflen,
  if(!t->out) {
    curl_msnprintf(t->filename, sizeof(t->filename)-1, "download_%zu.data",
                   t->idx);
-    t->out = fopen(t->filename, "wb");
+    t->out = curlx_fopen(t->filename, "wb");
    if(!t->out)
      return 0;
  }
@@ -530,7 +530,7 @@ static CURLcode test_cli_hx_download(const char *URL)
  for(i = 0; i < transfer_count_d; ++i) {
    t = &transfer_d[i];
    if(t->out) {
-      fclose(t->out);
+      curlx_fclose(t->out);
      t->out = NULL;
    }
    if(t->easy) {
--- a/tests/libtest/cli_hx_upload.c
+++ b/tests/libtest/cli_hx_upload.c
@@ -74,7 +74,7 @@ static size_t my_write_u_cb(char *buf, size_t nitems, size_t buflen,
  if(!t->out) {
    curl_msnprintf(t->filename, sizeof(t->filename)-1, "download_%zu.data",
                   t->idx);
-    t->out = fopen(t->filename, "wb");
+    t->out = curlx_fopen(t->filename, "wb");
    if(!t->out)
      return 0;
  }
@@ -494,7 +494,7 @@ static CURLcode test_cli_hx_upload(const char *URL)
  for(i = 0; i < transfer_count_u; ++i) {
    t = &transfer_u[i];
    if(t->out) {
-      fclose(t->out);
+      curlx_fclose(t->out);
      t->out = NULL;
    }
    if(t->easy) {
--- a/tests/libtest/lib500.c
+++ b/tests/libtest/lib500.c
@@ -90,7 +90,7 @@ static CURLcode test_lib500(const char *URL)
  if(!res) {
    res = curl_easy_getinfo(curl, CURLINFO_PRIMARY_IP, &ipstr);
    if(libtest_arg2) {
-      FILE *moo = fopen(libtest_arg2, "wb");
+      FILE *moo = curlx_fopen(libtest_arg2, "wb");
      if(moo) {
        curl_off_t time_namelookup;
        curl_off_t time_connect;
@@ -163,7 +163,7 @@ static CURLcode test_lib500(const char *URL)
                        (long)(time_total % 1000000));
        }

-        fclose(moo);
+        curlx_fclose(moo);
      }
    }
  }
--- a/tests/libtest/lib505.c
+++ b/tests/libtest/lib505.c
@@ -51,7 +51,7 @@ static CURLcode test_lib505(const char *URL)
    return TEST_ERR_USAGE;
  }

-  hd_src = fopen(libtest_arg2, "rb");
+  hd_src = curlx_fopen(libtest_arg2, "rb");
  if(!hd_src) {
    curl_mfprintf(stderr, "fopen failed with error (%d) %s\n",
                  errno, strerror(errno));
@@ -70,19 +70,19 @@ static CURLcode test_lib505(const char *URL)
    curl_mfprintf(stderr, "fstat() failed with error (%d) %s\n",
                  errno, strerror(errno));
    curl_mfprintf(stderr, "Error opening file '%s'\n", libtest_arg2);
-    fclose(hd_src);
+    curlx_fclose(hd_src);
    return TEST_ERR_MAJOR_BAD;
  }

  if(!file_info.st_size) {
    curl_mfprintf(stderr, "File %s has zero size!\n", libtest_arg2);
-    fclose(hd_src);
+    curlx_fclose(hd_src);
    return TEST_ERR_MAJOR_BAD;
  }

  if(curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK) {
    curl_mfprintf(stderr, "curl_global_init() failed\n");
-    fclose(hd_src);
+    curlx_fclose(hd_src);
    return TEST_ERR_MAJOR_BAD;
  }

@@ -91,7 +91,7 @@ static CURLcode test_lib505(const char *URL)
  if(!curl) {
    curl_mfprintf(stderr, "curl_easy_init() failed\n");
    curl_global_cleanup();
-    fclose(hd_src);
+    curlx_fclose(hd_src);
    return TEST_ERR_MAJOR_BAD;
  }

@@ -102,7 +102,7 @@ static CURLcode test_lib505(const char *URL)
    curl_mfprintf(stderr, "curl_slist_append() failed\n");
    curl_easy_cleanup(curl);
    curl_global_cleanup();
-    fclose(hd_src);
+    curlx_fclose(hd_src);
    return TEST_ERR_MAJOR_BAD;
  }
  headerlist = curl_slist_append(hl, buf_2);
@@ -111,7 +111,7 @@ static CURLcode test_lib505(const char *URL)
    curl_slist_free_all(hl);
    curl_easy_cleanup(curl);
    curl_global_cleanup();
-    fclose(hd_src);
+    curlx_fclose(hd_src);
    return TEST_ERR_MAJOR_BAD;
  }
  headerlist = hl;
@@ -144,7 +144,7 @@ test_cleanup:
  curl_slist_free_all(headerlist);

  /* close the local file */
-  fclose(hd_src);
+  curlx_fclose(hd_src);

  curl_easy_cleanup(curl);
  curl_global_cleanup();
--- a/tests/libtest/lib518.c
+++ b/tests/libtest/lib518.c
@@ -77,7 +77,7 @@ static int t518_fopen_works(void)
    fpa[i] = NULL;
  }
  for(i = 0; i < 3; i++) {
-    fpa[i] = fopen(DEV_NULL, FOPEN_READTEXT);
+    fpa[i] = curlx_fopen(DEV_NULL, FOPEN_READTEXT);
    if(!fpa[i]) {
      t518_store_errmsg("fopen failed", errno);
      curl_mfprintf(stderr, "%s\n", t518_msgbuff);
@@ -87,7 +87,7 @@ static int t518_fopen_works(void)
  }
  for(i = 0; i < 3; i++) {
    if(fpa[i])
-      fclose(fpa[i]);
+      curlx_fclose(fpa[i]);
  }
  return ret;
 }
--- a/tests/libtest/lib525.c
+++ b/tests/libtest/lib525.c
@@ -42,7 +42,7 @@ static CURLcode test_lib525(const char *URL)
    return TEST_ERR_USAGE;
  }

-  hd_src = fopen(libtest_arg2, "rb");
+  hd_src = curlx_fopen(libtest_arg2, "rb");
  if(!hd_src) {
    curl_mfprintf(stderr, "fopen failed with error (%d) %s\n",
                  errno, strerror(errno));
@@ -61,13 +61,13 @@ static CURLcode test_lib525(const char *URL)
    curl_mfprintf(stderr, "fstat() failed with error (%d) %s\n",
                  errno, strerror(errno));
    curl_mfprintf(stderr, "Error opening file '%s'\n", libtest_arg2);
-    fclose(hd_src);
+    curlx_fclose(hd_src);
    return TEST_ERR_FSTAT;
  }

  res_global_init(CURL_GLOBAL_ALL);
  if(res) {
-    fclose(hd_src);
+    curlx_fclose(hd_src);
    return res;
  }

@@ -149,7 +149,7 @@ test_cleanup:
  }

  /* close the local file */
-  fclose(hd_src);
+  curlx_fclose(hd_src);

  return res;
 }
--- a/tests/libtest/lib537.c
+++ b/tests/libtest/lib537.c
@@ -74,7 +74,7 @@ static int t537_fopen_works(void)
    fpa[i] = NULL;
  }
  for(i = 0; i < 3; i++) {
-    fpa[i] = fopen(DEV_NULL, FOPEN_READTEXT);
+    fpa[i] = curlx_fopen(DEV_NULL, FOPEN_READTEXT);
    if(!fpa[i]) {
      t537_store_errmsg("fopen failed", errno);
      curl_mfprintf(stderr, "%s\n", t537_msgbuff);
@@ -84,7 +84,7 @@ static int t537_fopen_works(void)
  }
  for(i = 0; i < 3; i++) {
    if(fpa[i])
-      fclose(fpa[i]);
+      curlx_fclose(fpa[i]);
  }
  return ret;
 }
--- a/tests/libtest/lib541.c
+++ b/tests/libtest/lib541.c
@@ -42,7 +42,7 @@ static CURLcode test_lib541(const char *URL)
    return TEST_ERR_USAGE;
  }

-  hd_src = fopen(libtest_arg2, "rb");
+  hd_src = curlx_fopen(libtest_arg2, "rb");
  if(!hd_src) {
    curl_mfprintf(stderr, "fopen failed with error (%d) %s\n",
                  errno, strerror(errno));
@@ -61,19 +61,19 @@ static CURLcode test_lib541(const char *URL)
    curl_mfprintf(stderr, "fstat() failed with error (%d) %s\n",
                  errno, strerror(errno));
    curl_mfprintf(stderr, "Error opening file '%s'\n", libtest_arg2);
-    fclose(hd_src);
+    curlx_fclose(hd_src);
    return TEST_ERR_MAJOR_BAD;
  }

  if(!file_info.st_size) {
    curl_mfprintf(stderr, "File %s has zero size!\n", libtest_arg2);
-    fclose(hd_src);
+    curlx_fclose(hd_src);
    return TEST_ERR_MAJOR_BAD;
  }

  if(curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK) {
    curl_mfprintf(stderr, "curl_global_init() failed\n");
-    fclose(hd_src);
+    curlx_fclose(hd_src);
    return TEST_ERR_MAJOR_BAD;
  }

@@ -82,7 +82,7 @@ static CURLcode test_lib541(const char *URL)
  if(!curl) {
    curl_mfprintf(stderr, "curl_easy_init() failed\n");
    curl_global_cleanup();
-    fclose(hd_src);
+    curlx_fclose(hd_src);
    return TEST_ERR_MAJOR_BAD;
  }

@@ -110,7 +110,7 @@ static CURLcode test_lib541(const char *URL)
 test_cleanup:

  /* close the local file */
-  fclose(hd_src);
+  curlx_fclose(hd_src);

  curl_easy_cleanup(curl);
  curl_global_cleanup();
--- a/tests/libtest/lib566.c
+++ b/tests/libtest/lib566.c
@@ -54,10 +54,10 @@ static CURLcode test_lib566(const char *URL)
    res = curl_easy_getinfo(curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD,
                            &content_length);

-    moo = fopen(libtest_arg2, "wb");
+    moo = curlx_fopen(libtest_arg2, "wb");
    if(moo) {
      curl_mfprintf(moo, "CL %.0f\n", content_length);
-      fclose(moo);
+      curlx_fclose(moo);
    }
  }

--- a/tests/libtest/lib568.c
+++ b/tests/libtest/lib568.c
@@ -75,7 +75,7 @@ static CURLcode test_lib568(const char *URL)
  fstat(sdp, &file_info);
  close(sdp);

-  sdpf = fopen(libtest_arg2, "rb");
+  sdpf = curlx_fopen(libtest_arg2, "rb");
  if(!sdpf) {
    curl_mfprintf(stderr, "can't fopen %s\n", libtest_arg2);
    res = TEST_ERR_MAJOR_BAD;
@@ -94,7 +94,7 @@ static CURLcode test_lib568(const char *URL)
    goto test_cleanup;

  test_setopt(curl, CURLOPT_UPLOAD, 0L);
-  fclose(sdpf);
+  curlx_fclose(sdpf);
  sdpf = NULL;

  /* Make sure we can do a normal request now */
@@ -159,7 +159,7 @@ static CURLcode test_lib568(const char *URL)
 test_cleanup:

  if(sdpf)
-    fclose(sdpf);
+    curlx_fclose(sdpf);

  curl_free(stream_uri);

--- a/tests/libtest/lib569.c
+++ b/tests/libtest/lib569.c
@@ -38,7 +38,7 @@ static CURLcode test_lib569(const char *URL)
  int request = 1;
  int i;

-  FILE *idfile = fopen(libtest_arg2, "wb");
+  FILE *idfile = curlx_fopen(libtest_arg2, "wb");
  if(!idfile) {
    curl_mfprintf(stderr, "couldn't open the Session ID File\n");
    return TEST_ERR_MAJOR_BAD;
@@ -46,7 +46,7 @@ static CURLcode test_lib569(const char *URL)

  if(curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK) {
    curl_mfprintf(stderr, "curl_global_init() failed\n");
-    fclose(idfile);
+    curlx_fclose(idfile);
    return TEST_ERR_MAJOR_BAD;
  }

@@ -54,7 +54,7 @@ static CURLcode test_lib569(const char *URL)
  if(!curl) {
    curl_mfprintf(stderr, "curl_easy_init() failed\n");
    curl_global_cleanup();
-    fclose(idfile);
+    curlx_fclose(idfile);
    return TEST_ERR_MAJOR_BAD;
  }

@@ -116,7 +116,7 @@ static CURLcode test_lib569(const char *URL)
 test_cleanup:

  if(idfile)
-    fclose(idfile);
+    curlx_fclose(idfile);

  curl_free(stream_uri);
  curl_easy_cleanup(curl);
--- a/tests/libtest/lib571.c
+++ b/tests/libtest/lib571.c
@@ -95,7 +95,7 @@ static CURLcode test_lib571(const char *URL)
  char *stream_uri = NULL;
  int request = 1;

-  FILE *protofile = fopen(libtest_arg2, "wb");
+  FILE *protofile = curlx_fopen(libtest_arg2, "wb");
  if(!protofile) {
    curl_mfprintf(stderr, "Couldn't open the protocol dump file\n");
    return TEST_ERR_MAJOR_BAD;
@@ -103,14 +103,14 @@ static CURLcode test_lib571(const char *URL)

  if(curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK) {
    curl_mfprintf(stderr, "curl_global_init() failed\n");
-    fclose(protofile);
+    curlx_fclose(protofile);
    return TEST_ERR_MAJOR_BAD;
  }

  curl = curl_easy_init();
  if(!curl) {
    curl_mfprintf(stderr, "curl_easy_init() failed\n");
-    fclose(protofile);
+    curlx_fclose(protofile);
    curl_global_cleanup();
    return TEST_ERR_MAJOR_BAD;
  }
@@ -194,7 +194,7 @@ test_cleanup:
  curl_free(stream_uri);

  if(protofile)
-    fclose(protofile);
+    curlx_fclose(protofile);

  curl_easy_cleanup(curl);
  curl_global_cleanup();
--- a/tests/libtest/lib572.c
+++ b/tests/libtest/lib572.c
@@ -93,7 +93,7 @@ static CURLcode test_lib572(const char *URL)
  fstat(params, &file_info);
  close(params);

-  paramsf = fopen(libtest_arg2, "rb");
+  paramsf = curlx_fopen(libtest_arg2, "rb");
  if(!paramsf) {
    curl_mfprintf(stderr, "can't fopen %s\n", libtest_arg2);
    res = TEST_ERR_MAJOR_BAD;
@@ -110,7 +110,7 @@ static CURLcode test_lib572(const char *URL)
    goto test_cleanup;

  test_setopt(curl, CURLOPT_UPLOAD, 0L);
-  fclose(paramsf);
+  curlx_fclose(paramsf);
  paramsf = NULL;

  /* Heartbeat GET_PARAMETERS */
@@ -163,7 +163,7 @@ static CURLcode test_lib572(const char *URL)
 test_cleanup:

  if(paramsf)
-    fclose(paramsf);
+    curlx_fclose(paramsf);

  curl_free(stream_uri);

--- a/tests/libtest/lib578.c
+++ b/tests/libtest/lib578.c
@@ -33,7 +33,7 @@ static size_t data_size = CURL_ARRAYSIZE(t578_testdata);
 static int t578_progress_callback(void *clientp, double dltotal, double dlnow,
                                  double ultotal, double ulnow)
 {
-  FILE *moo = fopen(libtest_arg2, "wb");
+  FILE *moo = curlx_fopen(libtest_arg2, "wb");

  (void)clientp;
  (void)dltotal;
@@ -45,7 +45,7 @@ static int t578_progress_callback(void *clientp, double dltotal, double dlnow,
    else
      curl_mfprintf(moo, "Progress callback called with UL %f out of %f\n",
                    ulnow, ultotal);
-    fclose(moo);
+    curlx_fclose(moo);
  }
  return 0;
 }
--- a/tests/libtest/lib579.c
+++ b/tests/libtest/lib579.c
@@ -35,11 +35,11 @@ static size_t last_ul_total = 0;

 static void progress_final_report(void)
 {
-  FILE *moo = fopen(libtest_arg2, "ab");
+  FILE *moo = curlx_fopen(libtest_arg2, "ab");
  curl_mfprintf(moo ? moo : stderr, "Progress: end UL %zu/%zu\n",
                last_ul, last_ul_total);
  if(moo)
-    fclose(moo);
+    curlx_fclose(moo);
  else
    curl_mfprintf(stderr, "Progress: end UL, can't open %s\n", libtest_arg2);
  started = FALSE;
@@ -59,11 +59,11 @@ static int t579_progress_callback(void *clientp, double dltotal, double dlnow,
  last_ul = (size_t)ulnow;
  last_ul_total = (size_t)ultotal;
  if(!started) {
-    FILE *moo = fopen(libtest_arg2, "ab");
+    FILE *moo = curlx_fopen(libtest_arg2, "ab");
    curl_mfprintf(moo ? moo : stderr, "Progress: start UL %zu/%zu\n",
                  last_ul, last_ul_total);
    if(moo)
-      fclose(moo);
+      curlx_fclose(moo);
    else
      curl_mfprintf(stderr, "Progress: start UL, can't open %s\n",
                    libtest_arg2);
--- a/tests/libtest/lib582.c
+++ b/tests/libtest/lib582.c
@@ -243,7 +243,7 @@ static CURLcode test_lib582(const char *URL)
    return TEST_ERR_USAGE;
  }

-  hd_src = fopen(libtest_arg2, "rb");
+  hd_src = curlx_fopen(libtest_arg2, "rb");
  if(!hd_src) {
    curl_mfprintf(stderr, "fopen() failed with error (%d) %s\n",
                  errno, strerror(errno));
@@ -262,7 +262,7 @@ static CURLcode test_lib582(const char *URL)
    curl_mfprintf(stderr, "fstat() failed with error (%d) %s\n",
                  errno, strerror(errno));
    curl_mfprintf(stderr, "Error opening file '%s'\n", libtest_arg2);
-    fclose(hd_src);
+    curlx_fclose(hd_src);
    return TEST_ERR_FSTAT;
  }
  curl_mfprintf(stderr, "Set to upload %" CURL_FORMAT_CURL_OFF_T " bytes\n",
@@ -270,7 +270,7 @@ static CURLcode test_lib582(const char *URL)

  res_global_init(CURL_GLOBAL_ALL);
  if(res != CURLE_OK) {
-    fclose(hd_src);
+    curlx_fclose(hd_src);
    return res;
  }

@@ -356,7 +356,7 @@ test_cleanup:
  curl_global_cleanup();

  /* close the local file */
-  fclose(hd_src);
+  curlx_fclose(hd_src);

  /* free local memory */
  free(sockets.read.sockets);
--- a/tests/libtest/lib591.c
+++ b/tests/libtest/lib591.c
@@ -39,7 +39,7 @@ static CURLcode test_lib591(const char *URL)

  start_test_timing();

-  upload = fopen(libtest_arg3, "rb");
+  upload = curlx_fopen(libtest_arg3, "rb");
  if(!upload) {
    curl_mfprintf(stderr, "fopen() failed with error (%d) %s\n",
                  errno, strerror(errno));
@@ -49,7 +49,7 @@ static CURLcode test_lib591(const char *URL)

  res_global_init(CURL_GLOBAL_ALL);
  if(res) {
-    fclose(upload);
+    curlx_fclose(upload);
    return res;
  }

@@ -138,7 +138,7 @@ test_cleanup:
  curl_global_cleanup();

  /* close the local file */
-  fclose(upload);
+  curlx_fclose(upload);

  return res;
 }
--- a/tests/libtest/lib599.c
+++ b/tests/libtest/lib599.c
@@ -82,10 +82,10 @@ static CURLcode test_lib599(const char *URL)
    FILE *moo;
    res = curl_easy_getinfo(curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD,
                            &content_length);
-    moo = fopen(libtest_arg2, "wb");
+    moo = curlx_fopen(libtest_arg2, "wb");
    if(moo) {
      curl_mfprintf(moo, "CL %.0f\n", content_length);
-      fclose(moo);
+      curlx_fclose(moo);
    }
  }

--- a/tests/libtest/lib678.c
+++ b/tests/libtest/lib678.c
@@ -30,7 +30,7 @@ static int loadfile(const char *filename, void **filedata, size_t *filesize)
  size_t datasize = 0;
  void *data = NULL;
  if(filename) {
-    FILE *fInCert = fopen(filename, "rb");
+    FILE *fInCert = curlx_fopen(filename, "rb");

    if(fInCert) {
      long cert_tell = 0;
@@ -48,7 +48,7 @@ static int loadfile(const char *filename, void **filedata, size_t *filesize)
      if((!data) ||
         ((int)fread(data, datasize, 1, fInCert) != 1))
        continue_reading = FALSE;
-      fclose(fInCert);
+      curlx_fclose(fInCert);
      if(!continue_reading) {
        free(data);
        datasize = 0;
--- a/tests/server/.checksrc
+++ b/tests/server/.checksrc
@@ -1,4 +1,6 @@
 allowfunc accept
+allowfunc fclose
+allowfunc fopen
 allowfunc freeaddrinfo
 allowfunc getaddrinfo
 allowfunc recv
--- a/tests/server/Makefile.inc
+++ b/tests/server/Makefile.inc
@@ -35,6 +35,7 @@ UTILS_H =

 CURLX_C = \
  ../../lib/curlx/base64.c \
+  ../../lib/curlx/fopen.c \
  ../../lib/curlx/inet_pton.c \
  ../../lib/curlx/inet_ntop.c \
  ../../lib/curlx/multibyte.c \
--- a/tests/unit/unit3200.c
+++ b/tests/unit/unit3200.c
@@ -84,12 +84,12 @@ static CURLcode test_unit3200(const char *arg)
    char *line;
    curlx_dyn_init(&buf, len);

-    fp = fopen(arg, "wb");
+    fp = curlx_fopen(arg, "wb");
    abort_unless(fp != NULL, "Cannot open testfile");
    fwrite(filecontents[i], 1, strlen(filecontents[i]), fp);
-    fclose(fp);
+    curlx_fclose(fp);

-    fp = fopen(arg, "rb");
+    fp = curlx_fopen(arg, "rb");
    abort_unless(fp != NULL, "Cannot open testfile");

    curl_mfprintf(stderr, "Test %zd...", i);
@@ -158,7 +158,7 @@ static CURLcode test_unit3200(const char *arg)
        break;
    }
    curlx_dyn_free(&buf);
-    fclose(fp);
+    curlx_fclose(fp);
    curl_mfprintf(stderr, "OK\n");
  }
  return (CURLcode)rc;