feat(cpp-client): utility function to read a password from stdin (dee…

…phaven#5849)
jcferretti · Jul 25, 2024 · 6b24b18 · 6b24b18
1 parent 215f3d7
commit 6b24b18
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diff --git a/cpp-client/deephaven/dhcore/include/public/deephaven/dhcore/utility/utility.h b/cpp-client/deephaven/dhcore/include/public/deephaven/dhcore/utility/utility.h
@@ -217,6 +217,18 @@ std::string Basename(std::string_view path);
  */
 [[nodiscard]] std::optional<std::string> GetEnv(const std::string& envname);
 
+/**
+ * Enables or disables echo for stdin.
+ * @param enable true to enable, false to disable
+ */
+void SetStdinEcho(bool enable);
+
+/**
+ * Reads a password from stdin up to pressing 'Enter', without echoing the characters typed.
+ * @return the password read
+ */
+std::string ReadPasswordFromStdinNoEcho();
+
 template <class T> [[nodiscard]] std::string
 TypeName(const T& t) {
   return demangle(typeid(t).name());

diff --git a/cpp-client/deephaven/dhcore/src/utility/utility.cc b/cpp-client/deephaven/dhcore/src/utility/utility.cc
@@ -23,6 +23,7 @@ static_assert(FMT_VERSION >= 100000);
 namespace deephaven::dhcore::utility {
 
 namespace {
+
 const char kEncodeLookup[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 const char kPadCharacter = '=';
 }  // namespace
@@ -167,4 +168,13 @@ std::string demangle(const char* name) {
 std::string ObjectId(const std::string &class_short_name, void *this_ptr) {
   return fmt::format("{}({})", class_short_name, this_ptr);
 }
+
+std::string ReadPasswordFromStdinNoEcho() {
+  SetStdinEcho(false);
+  std::string password;
+  std::cin >> password;
+  SetStdinEcho(true);
+  return password;
+}
+
 }  // namespace deephaven::dhcore::utility
diff --git a/cpp-client/deephaven/dhcore/src/utility/utility_platform_specific.cc b/cpp-client/deephaven/dhcore/src/utility/utility_platform_specific.cc
@@ -8,6 +8,7 @@
 
 #if defined(__unix__)
 #include <netdb.h>
+#include <termios.h>
 #include <unistd.h>
 #include <sys/syscall.h>
 #include <sys/socket.h>
@@ -17,6 +18,7 @@
 #endif
 
 namespace deephaven::dhcore::utility {
+
 std::string GetTidAsString() {
 #if defined(__linux__)
   const pid_t tid = syscall(__NR_gettid);  // this is more portable than gettid().
@@ -89,4 +91,32 @@ std::optional<std::string> GetEnv(const std::string& envname) {
 #error "Unsupported configuration"
 #endif
 }
+
+// https://stackoverflow.com/questions/1413445/reading-a-password-from-stdcin
+void SetStdinEcho(const bool enable) {
+#if defined(__unix__)
+  struct termios tty;
+  tcgetattr(STDIN_FILENO, &tty);
+  if( !enable )
+    tty.c_lflag &= ~ECHO;
+  else
+    tty.c_lflag |= ECHO;
+
+  (void) tcsetattr(STDIN_FILENO, TCSANOW, &tty);
+#elif defined(_WIN32)
+  HANDLE hStdin = GetStdHandle(STD_INPUT_HANDLE);
+  DWORD mode;
+  GetConsoleMode(hStdin, &mode);
+
+  if( !enable )
+    mode &= ~ENABLE_ECHO_INPUT;
+  else
+    mode |= ENABLE_ECHO_INPUT;
+
+  SetConsoleMode(hStdin, mode );
+#else
+#error "Unsupported configuration"
+#endif
+}    
+
 }  // namespace deephaven::dhcore::utility