cmCurlSetCAInfo: use std::string as argument

Source/cmCurl.cxx

@@ -31,11 +31,11 @@
     }                                                                         \
   } while (false)
 
-std::string cmCurlSetCAInfo(::CURL* curl, const char* cafile)
+std::string cmCurlSetCAInfo(::CURL* curl, const std::string& cafile)
 {
   std::string e;
-  if (cafile && *cafile) {
-    ::CURLcode res = ::curl_easy_setopt(curl, CURLOPT_CAINFO, cafile);
+  if (!cafile.empty()) {
+    ::CURLcode res = ::curl_easy_setopt(curl, CURLOPT_CAINFO, cafile.c_str());
     check_curl_result(res, "Unable to set TLS/SSL Verify CAINFO: ");
   }
 #ifdef CMAKE_FIND_CAFILE

Source/cmCurl.h

@@ -8,7 +8,7 @@
 
 #include <cm3p/curl/curl.h>
 
-std::string cmCurlSetCAInfo(::CURL* curl, const char* cafile = nullptr);
+std::string cmCurlSetCAInfo(::CURL* curl, const std::string& cafile = {});
 std::string cmCurlSetNETRCOption(::CURL* curl, const std::string& netrc_level,
                                  const std::string& netrc_file);
 std::string cmCurlFixFileURL(std::string url);

Source/cmFileCommand.cxx

@@ -1986,7 +1986,7 @@ bool HandleDownloadCommand(std::vector<std::string> const& args,
 
   // check to see if a CAINFO file has been specified
   // command arg comes first
-  std::string const& cainfo_err = cmCurlSetCAInfo(curl, cmToCStr(cainfo));
+  std::string const& cainfo_err = cmCurlSetCAInfo(curl, cainfo);
   if (!cainfo_err.empty()) {
     status.SetError(cainfo_err);
     return false;
@@ -2304,7 +2304,7 @@ bool HandleUploadCommand(std::vector<std::string> const& args,
 
   // check to see if a CAINFO file has been specified
   // command arg comes first
-  std::string const& cainfo_err = cmCurlSetCAInfo(curl, cmToCStr(cainfo));
+  std::string const& cainfo_err = cmCurlSetCAInfo(curl, cainfo);
   if (!cainfo_err.empty()) {
     status.SetError(cainfo_err);
     return false;

Source/cmGetPropertyCommand.cxx

@@ -2,6 +2,8 @@
    file Copyright.txt or https://cmake.org/licensing for details.  */
 #include "cmGetPropertyCommand.h"
 
+#include <cstddef>
+
 #include "cmExecutionStatus.h"
 #include "cmGlobalGenerator.h"
 #include "cmInstalledFile.h"