build: tidy-up MSVC CRT warning suppression macros

- curl_setup.h: replace `_CRT_SECURE_NO_DEPRECATE` with
  `_CRT_SECURE_NO_WARNINGS`, which seems to be the preferred,
  more recent macro for this. Also syncing with libssh2.
  They are equivalent for curl sources with the supported compilers.
- cmake: stop setting `_CRT_SECURE_NO_DEPRECATE` globally for examples.
- examples: suppress CRT deprecation warnings on a per-file basis.
  To make it work when compiling examples out of curl's build systems.
  Use `_CRT_SECURE_NO_WARNINGS`.
- examples: document the functions requiring `_CRT_SECURE_NO_WARNINGS`.
- examples/block_ip: delete superfluous `_CRT_SECURE_NO_WARNINGS`.
- examples/block_ip: limit `_CRT_NONSTDC_NO_DEPRECATE` to MSVC.
- examples/log_failed_transfers: fix to set `_CRT_SECURE_NO_WARNINGS`
  before headers and limit to MSVC.
- curl_setup.h: document which SDKs support `_CRT_NONSTDC_NO_DEPRECATE`.

Closes #19175

docs/examples/CMakeLists.txt

@@ -83,8 +83,7 @@ foreach(_target IN LISTS COMPLICATED_MAY_BUILD check_PROGRAMS _all)  # keep 'COM
     add_dependencies(curl-examples ${_target_name})
   endif()
   target_link_libraries(${_target_name} ${LIB_SELECTED} ${CURL_NETWORK_AND_TIME_LIBS} ${_more_libs})
-  target_compile_definitions(${_target_name} PRIVATE "CURL_NO_OLDIES"
-    "$<$<BOOL:${WIN32}>:WIN32_LEAN_AND_MEAN>" "$<$<BOOL:${MSVC}>:_CRT_SECURE_NO_DEPRECATE>")
+  target_compile_definitions(${_target_name} PRIVATE "CURL_NO_OLDIES" "$<$<BOOL:${WIN32}>:WIN32_LEAN_AND_MEAN>")
   set_target_properties(${_target_name} PROPERTIES OUTPUT_NAME "${_target}" PROJECT_LABEL "Example ${_target}" UNITY_BUILD OFF)
 endforeach()
 

docs/examples/anyauthput.c

@@ -26,6 +26,12 @@
  * one the server supports/wants.
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen() */
+#endif
+#endif
+
 #include <stdio.h>
 #include <fcntl.h>
 #include <sys/types.h>

docs/examples/block_ip.c

@@ -34,13 +34,13 @@
 int main(void) { printf("Platform not supported.\n"); return 1; }
 #else
 
-#ifdef _WIN32
-#ifndef _CRT_SECURE_NO_WARNINGS
-#define _CRT_SECURE_NO_WARNINGS
-#endif
+#ifdef _MSC_VER
 #ifndef _CRT_NONSTDC_NO_DEPRECATE
-#define _CRT_NONSTDC_NO_DEPRECATE
+#define _CRT_NONSTDC_NO_DEPRECATE  /* for strdup() */
 #endif
+#endif
+
+#ifdef _WIN32
 #if !defined(_WIN32_WINNT) || _WIN32_WINNT < 0x0600
 #undef _WIN32_WINNT
 #define _WIN32_WINNT 0x0600  /* Requires Windows Vista */

docs/examples/chkspeed.c

@@ -34,6 +34,11 @@
  * dd if=/dev/urandom of=file_1M.bin bs=1M count=1
  *
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for ctime() */
+#endif
+#endif
 
 #include <stdio.h>
 #include <stdlib.h>

docs/examples/cookie_interface.c

@@ -25,6 +25,11 @@
  * Import and export cookies with COOKIELIST.
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for _snprintf() */
+#endif
+#endif
 
 #include <stdio.h>
 #include <string.h>

docs/examples/externalsocket.c

@@ -26,6 +26,9 @@
  * </DESC>
  */
 #ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for strerror() */
+#endif
 #ifndef _WINSOCK_DEPRECATED_NO_WARNINGS
 #define _WINSOCK_DEPRECATED_NO_WARNINGS  /* for inet_addr() */
 #endif

docs/examples/fileupload.c

@@ -25,10 +25,17 @@
  * Upload to a file:// URL
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen() */
+#endif
+#endif
+
 #include <stdio.h>
-#include <curl/curl.h>
-#include <sys/stat.h>
 #include <fcntl.h>
+#include <sys/stat.h>
+
+#include <curl/curl.h>
 
 #ifdef _WIN32
 #undef stat

docs/examples/ftp-wildcard.c

@@ -25,9 +25,16 @@
  * FTP wildcard pattern matching
  * </DESC>
  */
-#include <curl/curl.h>
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen() */
+#endif
+#endif
+
 #include <stdio.h>
 
+#include <curl/curl.h>
+
 struct callback_data {
   FILE *output;
 };

docs/examples/ftpget.c

@@ -21,14 +21,19 @@
  * SPDX-License-Identifier: curl
  *
  ***************************************************************************/
-#include <stdio.h>
-
-#include <curl/curl.h>
-
 /* <DESC>
  * Get a single file from an FTP server.
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen() */
+#endif
+#endif
+
+#include <stdio.h>
+
+#include <curl/curl.h>
 
 struct FtpFile {
   const char *filename;

docs/examples/ftpgetinfo.c

@@ -21,15 +21,20 @@
  * SPDX-License-Identifier: curl
  *
  ***************************************************************************/
-#include <stdio.h>
-#include <string.h>
-
-#include <curl/curl.h>
-
 /* <DESC>
  * Checks a single file's size and mtime from an FTP server.
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen() */
+#endif
+#endif
+
+#include <stdio.h>
+#include <string.h>
+
+#include <curl/curl.h>
 
 static size_t throw_away(void *ptr, size_t size, size_t nmemb, void *data)
 {

docs/examples/ftpgetresp.c

@@ -21,15 +21,21 @@
  * SPDX-License-Identifier: curl
  *
  ***************************************************************************/
-#include <stdio.h>
-
-#include <curl/curl.h>
-
 /* <DESC>
  * Similar to ftpget.c but also stores the received response-lines
  * in a separate file using our own callback!
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen() */
+#endif
+#endif
+
+#include <stdio.h>
+
+#include <curl/curl.h>
+
 static size_t write_response(void *ptr, size_t size, size_t nmemb, void *data)
 {
   FILE *writehere = (FILE *)data;

docs/examples/ftpsget.c

@@ -21,15 +21,19 @@
  * SPDX-License-Identifier: curl
  *
  ***************************************************************************/
-
-#include <stdio.h>
-
-#include <curl/curl.h>
-
 /* <DESC>
  * Get a single file from an FTPS server.
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen() */
+#endif
+#endif
+
+#include <stdio.h>
+
+#include <curl/curl.h>
 
 struct FtpFile {
   const char *filename;

docs/examples/ftpupload.c

@@ -21,14 +21,26 @@
  * SPDX-License-Identifier: curl
  *
  ***************************************************************************/
+/* <DESC>
+ * Performs an FTP upload and renames the file just after a successful
+ * transfer.
+ * </DESC>
+ */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen(), strerror() */
+#endif
+#endif
+
 #include <stdio.h>
 #include <string.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
 
 #include <curl/curl.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <errno.h>
+
 #ifdef _WIN32
 #include <io.h>
 #undef stat
@@ -40,12 +52,6 @@
 #include <unistd.h>
 #endif
 
-/* <DESC>
- * Performs an FTP upload and renames the file just after a successful
- * transfer.
- * </DESC>
- */
-
 #define LOCAL_FILE      "/tmp/uploadthis.txt"
 #define UPLOAD_FILE_AS  "while-uploading.txt"
 #define REMOTE_URL      "ftp://example.com/"  UPLOAD_FILE_AS

docs/examples/ftpuploadresume.c

@@ -25,9 +25,15 @@
  * Upload to FTP, resuming failed transfers. Active mode.
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen(), sscanf() */
+#endif
+#endif
 
 #include <stdlib.h>
 #include <stdio.h>
+
 #include <curl/curl.h>
 
 /* parse headers for Content-Length */

docs/examples/hsts-preload.c

@@ -25,8 +25,15 @@
  * Preload domains to HSTS
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for strcpy() */
+#endif
+#endif
+
 #include <stdio.h>
 #include <string.h>
+
 #include <curl/curl.h>
 
 struct entry {

docs/examples/http2-download.c

@@ -25,15 +25,17 @@
  * Multiplexed HTTP/2 downloads over a single connection
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for _snprintf(), fopen(), strerror() */
+#endif
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <errno.h>
 
-#if defined(_MSC_VER) && (_MSC_VER < 1900)
-#define snprintf _snprintf
-#endif
-
 /* curl stuff */
 #include <curl/curl.h>
 
@@ -44,6 +46,10 @@
 #define CURLPIPE_MULTIPLEX 0L
 #endif
 
+#if defined(_MSC_VER) && (_MSC_VER < 1900)
+#define snprintf _snprintf
+#endif
+
 struct transfer {
   FILE *out;
   CURL *curl;

docs/examples/http2-serverpush.c

@@ -25,6 +25,12 @@
  * HTTP/2 server push
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for _snprintf(), fopen() */
+#endif
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -32,14 +38,14 @@
 /* curl stuff */
 #include <curl/curl.h>
 
-#if defined(_MSC_VER) && (_MSC_VER < 1900)
-#define snprintf _snprintf
-#endif
-
 #ifndef CURLPIPE_MULTIPLEX
 #error "too old libcurl, cannot do HTTP/2 server push!"
 #endif
 
+#if defined(_MSC_VER) && (_MSC_VER < 1900)
+#define snprintf _snprintf
+#endif
+
 static FILE *out_download;
 
 static void dump(const char *text, unsigned char *ptr, size_t size, char nohex)

docs/examples/http2-upload.c

@@ -25,6 +25,13 @@
  * Multiplexed HTTP/2 uploads over a single connection
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for '_snprintf(), fopen(), localtime(),
+                                    strerror() */
+#endif
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -38,6 +45,16 @@
 #include <unistd.h>
 #endif
 
+/* curl stuff */
+#include <curl/curl.h>
+
+#ifndef CURLPIPE_MULTIPLEX
+/* This little trick makes sure that we do not enable pipelining for libcurls
+   old enough to not have this symbol. It is _not_ defined to zero in a recent
+   libcurl header. */
+#define CURLPIPE_MULTIPLEX 0L
+#endif
+
 #ifdef _WIN32
 #undef stat
 #define stat _stat
@@ -50,16 +67,6 @@
 #define snprintf _snprintf
 #endif
 
-/* curl stuff */
-#include <curl/curl.h>
-
-#ifndef CURLPIPE_MULTIPLEX
-/* This little trick makes sure that we do not enable pipelining for libcurls
-   old enough to not have this symbol. It is _not_ defined to zero in a recent
-   libcurl header. */
-#define CURLPIPE_MULTIPLEX 0L
-#endif
-
 #ifdef _MSC_VER
 #define gettimeofday(a, b) my_gettimeofday((a), (b))
 static int my_gettimeofday(struct timeval *tp, void *tzp)

docs/examples/httpput.c

@@ -25,6 +25,12 @@
  * HTTP PUT with easy interface and read callback
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen() */
+#endif
+#endif
+
 #include <stdio.h>
 #include <fcntl.h>
 #include <sys/stat.h>

docs/examples/log_failed_transfers.c

@@ -31,18 +31,21 @@
  * The transfer's log is written to disk only if the transfer fails.
  *
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen(), strerror(), vsnprintf() */
+#endif
+#endif
 
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <limits.h>
 #include <string.h>
+
 #include <curl/curl.h>
 
 #ifdef _WIN32
-#ifndef _CRT_SECURE_NO_WARNINGS
-#define _CRT_SECURE_NO_WARNINGS
-#endif
 #include <windows.h>
 #define strcasecmp _stricmp
 #define strncasecmp _strnicmp

docs/examples/sepheaders.c

@@ -25,6 +25,12 @@
  * Simple HTTP GET that stores the headers in a separate file
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen() */
+#endif
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 

docs/examples/sftpget.c

@@ -25,6 +25,11 @@
  * Gets a file using an SFTP URL.
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen() */
+#endif
+#endif
 
 #include <stdio.h>
 

docs/examples/sftpuploadresume.c

@@ -25,9 +25,15 @@
  * Upload to SFTP, resuming a previously aborted transfer.
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen() */
+#endif
+#endif
 
 #include <stdlib.h>
 #include <stdio.h>
+
 #include <curl/curl.h>
 
 /* read data to upload */

docs/examples/simplessl.c

@@ -25,6 +25,12 @@
  * Shows HTTPS usage with client certs and optional ssl engine use.
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen() */
+#endif
+#endif
+
 #include <stdio.h>
 
 #include <curl/curl.h>

docs/examples/synctime.c

@@ -56,6 +56,12 @@
  * This software synchronises your computer clock only when you issue
  * it with --synctime. By default, it only display the webserver's clock.
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for _snprintf(), fopen(), gmtime(),
+                                    localtime(), sscanf() */
+#endif
+#endif
 
 #include <stdio.h>
 

docs/examples/url2file.c

@@ -25,6 +25,12 @@
  * Download a given URL into a local file named page.out.
  * </DESC>
  */
+#ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for fopen() */
+#endif
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 

lib/curl_setup.h

@@ -90,11 +90,15 @@
 /* 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
-#define _CRT_NONSTDC_NO_DEPRECATE  /* for strdup(), write(), etc. */
+#ifndef _CRT_NONSTDC_NO_DEPRECATE  /* mingw-w64 v2+. MS SDK ~10+/~VS2017+. */
+#define _CRT_NONSTDC_NO_DEPRECATE  /* for close(), fileno(), strdup(),
+                                      unlink(), etc. */
 #endif
-#ifndef _CRT_SECURE_NO_DEPRECATE
-#define _CRT_SECURE_NO_DEPRECATE  /* for fopen(), getenv(), etc. */
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS  /* for __sys_errlist, __sys_nerr, _wfopen(),
+                                    _wopen(), freopen(), getenv(), gmtime(),
+                                    sprintf(), strcpy(), wcscpy(), wcsncpy()
+                                    in tests: localtime(), open(), sscanf() */
 #endif
 #endif /* _MSC_VER */