[PATCH setup 07/11] Add symlink capabilities to user-agent telemetry

[Jon Turney <jon.turney@dronecode.org.uk>]

Report if (i) we have the symlink creation privilege, and (ii) if
developer mode is on, so unprivileged symlink creation is allowed.
---
 nio-ie5.cc | 12 +++++++++++-
 win32.cc   | 18 ++++++++++++++++++
 win32.h    |  1 +
 3 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/nio-ie5.cc b/nio-ie5.cc
index e93d6d4..8fd7008 100644
--- a/nio-ie5.cc
+++ b/nio-ie5.cc
@@ -89,7 +89,17 @@ determine_default_useragent(void)
       langid << std::hex << std::setw(4) << std::setfill('0') << l;
     }
 
-  default_useragent = std::string("Cygwin-Setup/") + setup_version + " (" + os.str() + ";" + bitness + ";" + langid.str() + ")";
+  std::string symlinks = "";
+  if (nt_sec.hasSymlinkCreationRights())
+    symlinks.append("SymLinkPriv");
+  if (is_developer_mode())
+    {
+      if (!symlinks.empty())
+        symlinks.append("+");
+      symlinks.append("UnprivilegedSymLink");
+    }
+
+  default_useragent = std::string("Cygwin-Setup/") + setup_version + " (" + os.str() + ";" + bitness + ";" + langid.str() + ";" + symlinks + ")";
   Log (LOG_BABBLE) << "User-Agent: default is \"" << default_useragent << "\"" << endLog;
 
   return default_useragent;
diff --git a/win32.cc b/win32.cc
index 6455384..db79fd7 100644
--- a/win32.cc
+++ b/win32.cc
@@ -492,3 +492,21 @@ LoadStringW(unsigned int uID)
 
   return L"";
 }
+
+bool
+is_developer_mode(void)
+{
+  HKEY hKey;
+  LSTATUS err = RegOpenKeyExW(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\AppModelUnlock", 0, KEY_READ, &hKey);
+  if (err != ERROR_SUCCESS)
+    return false;
+
+  DWORD value;
+  DWORD size = sizeof(DWORD);
+  err = RegQueryValueExW(hKey, L"AllowDevelopmentWithoutDevLicense", NULL, NULL, reinterpret_cast<LPBYTE>(&value), &size);
+  RegCloseKey(hKey);
+  if (err != ERROR_SUCCESS)
+    return false;
+
+  return value != 0;
+}
diff --git a/win32.h b/win32.h
index e498077..5874d8b 100644
--- a/win32.h
+++ b/win32.h
@@ -196,5 +196,6 @@ SetDlgItemRect (HWND h, int item, LPRECT r)
 }
 
 const std::wstring LoadStringW(unsigned int uID);
+bool is_developer_mode(void);
 
 #endif /* SETUP_WIN32_H */
-- 
2.32.0