build: update to not need _CRT_NONSTDC_NO_DEPRECATE with MSVC

Use non-deprecated CRT function variants on Windows.

- introduce `curlx_fdopen()`, `curlx_close()` and use them. Map them to
  non-deprecated, underscored, CRT functions on Windows.

- replace `close()` uses with either `sclose()` (for sockets) or
  `curlx_close()` (for files).

- map `fileno`, `unlink`, `isatty` to their non-deprecated, underscored,
  versions on Windows.

- tool_dirhie: map `mkdir` to `_mkdir` on Windows.

- easy: use `_strdup()` on Windows, regardless of how `HAVE_STRDUP` is
  set.

- cmake: assume `HAVE_STRDUP` on Windows. To allow dropping a detection
  hack using `_CRT_NONSTDC_NO_DEPRECATE` with MSVC. Windows always has
  `_strdup()` which the code uses, but also needs `HAVE_STRDUP` defined
  to disable curl's own `strdup()` implementation.

- curl_setup.h: drop `_CRT_NONSTDC_NO_DEPRECATE` as no longer necessary.

Closes #20212

lib/cf-socket.c

@@ -349,7 +349,7 @@ static CURLcode socket_open(struct Curl_easy *data,
   if(fcntl(*sockfd, F_SETFD, FD_CLOEXEC) < 0) {
     failf(data, "fcntl set CLOEXEC: %s",
           curlx_strerror(SOCKERRNO, errbuf, sizeof(errbuf)));
-    close(*sockfd);
+    sclose(*sockfd);
     *sockfd = CURL_SOCKET_BAD;
     return CURLE_COULDNT_CONNECT;
   }

lib/curl_fopen.c

@@ -147,7 +147,7 @@ CURLcode Curl_fopen(struct Curl_easy *data, const char *filename,
 
 fail:
   if(fd != -1) {
-    close(fd);
+    curlx_close(fd);
     unlink(tempstore);
   }
 

lib/curl_setup.h

@@ -89,10 +89,6 @@
 #ifdef _MSC_VER
 /* Disable Visual Studio warnings: 4127 "conditional expression is constant" */
 #pragma warning(disable:4127)
-/* Avoid VS2005 and upper complaining about portable C functions. */
-#ifndef _CRT_NONSTDC_NO_DEPRECATE  /* mingw-w64 v2+. MS SDK ~10+/~VS2017+. */
-#define _CRT_NONSTDC_NO_DEPRECATE  /* for close(), fileno(), unlink(), etc. */
-#endif
 #ifndef _CRT_SECURE_NO_WARNINGS
 #define _CRT_SECURE_NO_WARNINGS  /* for getenv(), tests: sscanf() */
 #endif
@@ -808,6 +804,13 @@
 #  define read(fd, buf, count)  (ssize_t)_read(fd, buf, curlx_uztoui(count))
 #  undef  write
 #  define write(fd, buf, count) (ssize_t)_write(fd, buf, curlx_uztoui(count))
+/* Avoid VS2005+ _CRT_NONSTDC_NO_DEPRECATE warnings about non-portable funcs */
+#  undef fileno
+#  define fileno(fh) _fileno(fh)
+#  undef unlink
+#  define unlink(fn) _unlink(fn)
+#  undef isatty
+#  define isatty(fd) _isatty(fd)
 #endif
 
 /*

lib/curlx/fopen.h

@@ -50,14 +50,18 @@ int curlx_win32_open(const char *filename, int oflag, ...);
 int curlx_win32_rename(const char *oldpath, const char *newpath);
 #define CURLX_FOPEN_LOW(fname, mode)       curlx_win32_fopen(fname, mode)
 #define CURLX_FREOPEN_LOW(fname, mode, fh) curlx_win32_freopen(fname, mode, fh)
+#define CURLX_FDOPEN_LOW                   _fdopen
 #define curlx_stat(fname, stp)             curlx_win32_stat(fname, stp)
 #define curlx_open                         curlx_win32_open
+#define curlx_close                        _close
 #define curlx_rename                       curlx_win32_rename
 #else
 #define CURLX_FOPEN_LOW                    fopen
 #define CURLX_FREOPEN_LOW                  freopen
+#define CURLX_FDOPEN_LOW                   fdopen
 #define curlx_stat(fname, stp)             stat(fname, stp)
 #define curlx_open                         open
+#define curlx_close                        close
 #define curlx_rename                       rename
 #endif
 
@@ -71,7 +75,7 @@ int curlx_win32_rename(const char *oldpath, const char *newpath);
 #else
 #define curlx_fopen             CURLX_FOPEN_LOW
 #define curlx_freopen           CURLX_FREOPEN_LOW
-#define curlx_fdopen            fdopen
+#define curlx_fdopen            CURLX_FDOPEN_LOW
 #define curlx_fclose            fclose
 #endif
 

lib/easy.c

@@ -99,12 +99,10 @@ static curl_simple_lock s_lock = CURL_SIMPLE_LOCK_INIT;
  * ways, but at this point it must be defined as the system-supplied strdup
  * so the callback pointer is initialized correctly.
  */
-#ifdef HAVE_STRDUP
 #ifdef _WIN32
 #define system_strdup _strdup
-#else
+#elif defined(HAVE_STRDUP)
 #define system_strdup strdup
-#endif
 #else
 #define system_strdup Curl_strdup
 #endif

lib/file.c

@@ -87,7 +87,7 @@ static void file_cleanup(struct FILEPROTO *file)
   Curl_safefree(file->freepath);
   file->path = NULL;
   if(file->fd != -1) {
-    close(file->fd);
+    curlx_close(file->fd);
     file->fd = -1;
   }
 }
@@ -312,7 +312,7 @@ static CURLcode file_upload(struct Curl_easy *data,
   /* treat the negative resume offset value as the case of "-" */
   if(data->state.resume_from < 0) {
     if(fstat(fd, &file_stat)) {
-      close(fd);
+      curlx_close(fd);
       failf(data, "cannot get the size of %s", file->path);
       return CURLE_WRITE_ERROR;
     }
@@ -367,7 +367,7 @@ static CURLcode file_upload(struct Curl_easy *data,
     result = Curl_pgrsUpdate(data);
 
 out:
-  close(fd);
+  curlx_close(fd);
   Curl_multi_xfer_ulbuf_release(data, xfer_ulbuf);
 
   return result;

lib/memdebug.c

@@ -497,8 +497,7 @@ ALLOC_FUNC
 FILE *curl_dbg_fdopen(int filedes, const char *mode,
                       int line, const char *source)
 {
-  /* !checksrc! disable BANNEDFUNC 1 */
-  FILE *res = fdopen(filedes, mode);
+  FILE *res = CURLX_FDOPEN_LOW(filedes, mode);
   if(source)
     curl_dbg_log("FILE %s:%d fdopen(\"%d\",\"%s\") = %p\n",
                  source, line, filedes, mode, (void *)res);

lib/socketpair.c

@@ -64,8 +64,8 @@ static int wakeup_pipe(curl_socket_t socks[2], bool nonblocking)
 #ifdef HAVE_FCNTL
   if(fcntl(socks[0], F_SETFD, FD_CLOEXEC) ||
      fcntl(socks[1], F_SETFD, FD_CLOEXEC)) {
-    close(socks[0]);
-    close(socks[1]);
+    sclose(socks[0]);
+    sclose(socks[1]);
     socks[0] = socks[1] = CURL_SOCKET_BAD;
     return -1;
   }
@@ -73,8 +73,8 @@ static int wakeup_pipe(curl_socket_t socks[2], bool nonblocking)
   if(nonblocking) {
     if(curlx_nonblock(socks[0], TRUE) < 0 ||
        curlx_nonblock(socks[1], TRUE) < 0) {
-      close(socks[0]);
-      close(socks[1]);
+      sclose(socks[0]);
+      sclose(socks[1]);
       socks[0] = socks[1] = CURL_SOCKET_BAD;
       return -1;
     }
@@ -107,8 +107,8 @@ static int wakeup_socketpair(curl_socket_t socks[2], bool nonblocking)
   if(nonblocking) {
     if(curlx_nonblock(socks[0], TRUE) < 0 ||
        curlx_nonblock(socks[1], TRUE) < 0) {
-      close(socks[0]);
-      close(socks[1]);
+      sclose(socks[0]);
+      sclose(socks[1]);
       return -1;
     }
   }

lib/vquic/curl_ngtcp2.c

@@ -55,6 +55,7 @@
 #include "../cf-socket.h"
 #include "../connect.h"
 #include "../progress.h"
+#include "../curlx/fopen.h"
 #include "../curlx/dynbuf.h"
 #include "../http1.h"
 #include "../select.h"
@@ -449,7 +450,7 @@ static void qlog_callback(void *user_data, uint32_t flags,
     ssize_t rc = write(ctx->qlogfd, data, datalen);
     if(rc == -1) {
       /* on write error, stop further write attempts */
-      close(ctx->qlogfd);
+      curlx_close(ctx->qlogfd);
       ctx->qlogfd = -1;
     }
   }
@@ -2140,7 +2141,7 @@ static void cf_ngtcp2_ctx_close(struct cf_ngtcp2_ctx *ctx)
   if(!ctx->initialized)
     return;
   if(ctx->qlogfd != -1) {
-    close(ctx->qlogfd);
+    curlx_close(ctx->qlogfd);
   }
   ctx->qlogfd = -1;
   Curl_vquic_tls_cleanup(&ctx->tls);