commit cfe4bd1121b3007229be2f59fc4a46be715a662c
Author: Daniel Swanson <popcorn.tomato.dude@gmail.com>
Date:   Tue Jul 6 14:06:55 2021 -0500

    InputFile helper for reading blanks

diff --git a/lttoolbox/input_file.cc b/lttoolbox/input_file.cc
index 0d910f6..1994fd8 100644
--- a/lttoolbox/input_file.cc
+++ b/lttoolbox/input_file.cc
@@ -197,3 +197,41 @@ InputFile::finishWBlank()
   }
   return ret;
 }
+
+UString
+InputFile::readBlank(bool readwblank)
+{
+  UString ret;
+  while (!eof()) {
+    UChar32 c = get();
+    if (c == '^' || c == '\0' || c == U_EOF) {
+      unget(c);
+      break;
+    } else if (c == '[') {
+      UChar32 c2 = get();
+      if (c2 == '[') {
+        if (readwblank) {
+          ret += finishWBlank();
+        } else {
+          // buffer size is 3, so we should be ok here
+          unget(c2);
+          unget(c);
+          break;
+        }
+      } else {
+        unget(c2);
+        ret += readBlock(c2, ']');
+      }
+    } else {
+      ret += c;
+      if (c == '\\') {
+        if (eof() || peek() == '\0') {
+          std::cerr << "Unexpected trailing backslash" << std::endl;
+          exit(EXIT_FAILURE);
+        }
+        ret += get();
+      }
+    }
+  }
+  return ret;
+}
diff --git a/lttoolbox/input_file.h b/lttoolbox/input_file.h
index de031c8..dffcf7f 100644
--- a/lttoolbox/input_file.h
+++ b/lttoolbox/input_file.h
@@ -49,6 +49,10 @@ public:
   // assumes [[ has already been read, reads to ]]
   // returns entire string, including brackets
   UString finishWBlank();
+  // read until ^ or \0
+  // if readwblank == false, also stop at [[
+  // Note: relies on the fact that ubuffer has length >= 2
+  UString readBlank(bool readwblank = false);
 };
 
 #endif