1 files changed, 72 insertions, 0 deletions
diff --git a/src/jsutil.cc b/src/jsutil.cc
new file mode 100644
index 0000000..ca74b48
--- /dev/null
+++ b/src/jsutil.cc
@@ -0,0 +1,72 @@
+#include "common.hh"
+
+#include "jsutil.hh"
+
+namespace js {
+
+namespace {
+
+constexpr const char kSingleQuoteChars[] = "'\0\\\n\r\v\t\b\f";
+constexpr const char kDoubleQuoteChars[] = "\"\0\\\n\r\v\t\b\f";
+
+}  // namespace
+
+std::string quote(std::string_view in, QuoteChar quote_char) {
+  std::string ret;
+  quote(in, ret, quote_char);
+  return ret;
+}
+
+void quote(std::string_view in, std::string& out, QuoteChar quote_char) {
+  out.reserve(out.size() + 2 + in.size());
+  std::string_view chars;
+  switch (quote_char) {
+  case QuoteChar::SINGLE:
+    chars = std::string_view(kSingleQuoteChars, sizeof(kSingleQuoteChars) - 1);
+    break;
+  case QuoteChar::DOUBLE:
+    chars = std::string_view(kDoubleQuoteChars, sizeof(kDoubleQuoteChars) - 1);
+    break;
+  }
+  out.push_back(chars.front());
+  size_t last = 0;
+  while (true) {
+    auto next = in.find_first_of(chars, last);
+    if (next == std::string::npos) {
+      out.append(in, last);
+      break;
+    }
+    out.append(in, last, next - last);
+    out.push_back('\\');
+    switch (in[next]) {
+    case '\0':
+      out.push_back('0');
+      break;
+    case '\n':
+      out.push_back('n');
+      break;
+    case '\r':
+      out.push_back('r');
+      break;
+    case '\v':
+      out.push_back('v');
+      break;
+    case '\t':
+      out.push_back('t');
+      break;
+    case '\b':
+      out.push_back('b');
+      break;
+    case '\f':
+      out.push_back('f');
+      break;
+    default:
+      out.push_back(in[next]);
+      break;
+    }
+    last = next + 1;
+  }
+  out.push_back(chars.front());
+}
+
+}  // namespace js