AK+Kernel: Escape JSON keys & values

Grab the escaping logic from JSON string value serialization and use
it for serializing all keys and values.

Fixes #3917.

2 files changed, 30 insertions, 0 deletions

diff --git a/Kernel/KBufferBuilder.cpp b/Kernel/KBufferBuilder.cpp
index 1c3129be4e..f3480b10a2 100644
--- a/Kernel/KBufferBuilder.cpp
+++ b/Kernel/KBufferBuilder.cpp
@@ -93,4 +93,32 @@ void KBufferBuilder::appendf(const char* fmt, ...)
     va_end(ap);
 }
 
+void KBufferBuilder::append_escaped_for_json(const StringView& string)
+{
+    for (auto ch : string) {
+        switch (ch) {
+        case '\e':
+            append("\\u001B");
+            break;
+        case '\b':
+            append("\\b");
+            break;
+        case '\n':
+            append("\\n");
+            break;
+        case '\t':
+            append("\\t");
+            break;
+        case '\"':
+            append("\\\"");
+            break;
+        case '\\':
+            append("\\\\");
+            break;
+        default:
+            append(ch);
+        }
+    }
+}
+
 }
diff --git a/Kernel/KBufferBuilder.h b/Kernel/KBufferBuilder.h
index affef2bbe8..9335620a02 100644
--- a/Kernel/KBufferBuilder.h
+++ b/Kernel/KBufferBuilder.h
@@ -45,6 +45,8 @@ public:
     void appendf(const char*, ...);
     void appendvf(const char*, va_list);
 
+    void append_escaped_for_json(const StringView&);
+
     template<typename... Parameters>
     void appendff(StringView fmtstr, const Parameters&... parameters)
     {