Merge GH #1678 Add read_kv utility function

1 files changed, 85 insertions, 0 deletions

diff --git a/src/lib/utils/read_kv.cpp b/src/lib/utils/read_kv.cpp
new file mode 100644
index 000000000..cdc84c622
--- /dev/null
+++ b/src/lib/utils/read_kv.cpp
@@ -0,0 +1,85 @@
+/*
+* (C) 2018 Ribose Inc
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/parsing.h>
+#include <botan/exceptn.h>
+
+namespace Botan {
+
+std::map<std::string, std::string> read_kv(const std::string& kv)
+   {
+   std::map<std::string, std::string> m;
+   if(kv == "")
+      return m;
+
+   std::vector<std::string> parts;
+
+   try
+      {
+      parts = split_on(kv, ',');
+      }
+   catch(std::exception&)
+      {
+      throw Invalid_Argument("Bad KV spec");
+      }
+
+   bool escaped = false;
+   bool reading_key = true;
+   std::string cur_key;
+   std::string cur_val;
+
+   for(char c : kv)
+      {
+      if(c == '\\' && !escaped)
+         {
+         escaped = true;
+         }
+      else if(c == ',' && !escaped)
+         {
+         if(cur_key.empty())
+            throw Invalid_Argument("Bad KV spec empty key");
+
+         if(m.find(cur_key) != m.end())
+            throw Invalid_Argument("Bad KV spec duplicated key");
+         m[cur_key] = cur_val;
+         cur_key = "";
+         cur_val = "";
+         reading_key = true;
+         }
+      else if(c == '=' && !escaped)
+         {
+         if(reading_key == false)
+            throw Invalid_Argument("Bad KV spec unexpected equals sign");
+         reading_key = false;
+         }
+      else
+         {
+         if(reading_key)
+            cur_key += c;
+         else
+            cur_val += c;
+
+         if(escaped)
+            escaped = false;
+         }
+      }
+
+   if(!cur_key.empty())
+      {
+      if(reading_key == false)
+         {
+         if(m.find(cur_key) != m.end())
+            throw Invalid_Argument("Bad KV spec duplicated key");
+         m[cur_key] = cur_val;
+         }
+      else
+         throw Invalid_Argument("Bad KV spec incomplete string");
+      }
+
+   return m;
+   }
+
+}