add notcurses_debug() #594

include/notcurses/notcurses.h

@@ -2842,6 +2842,10 @@ API char* ncreader_contents(const struct ncreader* n);
 // UTF-8 input will be heap-duplicated and written to 'contents'.
 API void ncreader_destroy(struct ncreader* n, char** contents);
 
+// Dump selected notcurses state to the supplied 'debugfp'. Output is freeform,
+// and subject to change. It includes geometry of all planes.
+API void notcurses_debug(struct notcurses* nc, FILE* debugfp);
+
 #undef API
 
 #ifdef __cplusplus

src/lib/debug.c

@@ -0,0 +1,14 @@
+#include "internal.h"
+
+void notcurses_debug(notcurses* nc, FILE* debugfp){
+  const ncplane* n = nc->top;
+  int planeidx = 0;
+  fprintf(debugfp, "********************* notcurses debug state *********************\n");
+  while(n){
+    fprintf(debugfp, "%04d off y: %3d x: %3d geom y: %3d x: %3d %s\n",
+            planeidx, n->y, n->x, n->leny, n->lenx,
+            n == notcurses_stdplane_const(nc) ? "std" : "   ");
+    n = n->z;
+  }
+  fprintf(debugfp, "*****************************************************************\n");
+}