Add API to set terminal fallback size (#230)

In case of embedded systems, the terminal size may not always be detectable (e.g. in case of serial output). Allow application to set up the default size in case autodetection fails. On platform such as Emscripten, there is only "fallback" size. Signed-off-by: Jarosław Pelczar <[email protected]>
ArthurSonzogni · Oct 13, 2021 · 7298636 · 7298636
1 parent 5e199fc
commit 7298636
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Showing 2 changed files with 19 additions and 4 deletions.
diff --git a/include/ftxui/screen/terminal.hpp b/include/ftxui/screen/terminal.hpp
@@ -9,6 +9,7 @@ struct Dimensions {
 
 namespace Terminal {
 Dimensions Size();
+void SetFallbackSize(const Dimensions& fallbackSize);
 
 enum Color {
   Palette1,

diff --git a/src/ftxui/screen/terminal.cpp b/src/ftxui/screen/terminal.cpp
@@ -18,9 +18,18 @@
 
 namespace ftxui {
 
+#if defined(__EMSCRIPTEN__)
+static Dimensions fallback_size{140, 43};
+#elif defined(_WIN32)
+// The Microsoft default "cmd" returns errors above.
+static Dimensions fallback_size{80, 80};
+#else
+static Dimensions fallback_size{80, 25};
+#endif
+
 Dimensions Terminal::Size() {
 #if defined(__EMSCRIPTEN__)
-  return Dimensions{140, 43};
+  return fallback_size;
 #elif defined(_WIN32)
   CONSOLE_SCREEN_BUFFER_INFO csbi;
 
@@ -29,19 +38,24 @@ Dimensions Terminal::Size() {
                       csbi.srWindow.Bottom - csbi.srWindow.Top + 1};
   }
 
-  // The Microsoft default "cmd" returns errors above.
-  return Dimensions{80, 80};
+  return fallback_size;
 
 #else
   winsize w{};
   ioctl(STDOUT_FILENO, TIOCGWINSZ, &w);
   if (w.ws_col == 0 || w.ws_row == 0) {
-    return Dimensions{80, 25};
+    return fallback_size;
   }
   return Dimensions{w.ws_col, w.ws_row};
 #endif
 }
 
+/// @brief Override terminal size in case auto-detection fails
+/// @param fallbackSize Terminal dimensions to fallback to
+void Terminal::SetFallbackSize(const Dimensions& fallbackSize) {
+  fallback_size = fallbackSize;
+}
+
 namespace {
 
 const char* Safe(const char* c) {