Modify areas that still assumed Pipe::message_id was exactly a u32bit.

This was done by replacing Pipe::message_id with a completely opaque
type and adding only the necessary operations. In this revision
Pipe::message_id does remain a u32bit. However it may become an
opaque type in the future.

Move the Invalid_Message_Number exception to Pipe since that is the only
piece of code which throws it.

6 files changed, 40 insertions, 35 deletions

diff --git a/include/exceptn.h b/include/exceptn.h
index 1381782cf..5b0106105 100644
--- a/include/exceptn.h
+++ b/include/exceptn.h
@@ -60,14 +60,6 @@ struct Invalid_IV_Length : public Invalid_Argument
    };
 
 /*************************************************
-* Invalid_Message_Number Exception               *
-*************************************************/
-struct Invalid_Message_Number : public Invalid_Argument
-   {
-   Invalid_Message_Number(const std::string&, u32bit);
-   };
-
-/*************************************************
 * Invalid_State Exception                        *
 *************************************************/
 struct Invalid_State : public Exception
diff --git a/include/out_buf.h b/include/out_buf.h
index 8965e3895..1e169b9bc 100644
--- a/include/out_buf.h
+++ b/include/out_buf.h
@@ -7,6 +7,7 @@
 #define BOTAN_OUTPUT_BUFFER_H__
 
 #include <botan/types.h>
+#include <botan/pipe.h>
 #include <deque>
 
 namespace Botan {
@@ -17,22 +18,22 @@ namespace Botan {
 class Output_Buffers
    {
    public:
-      u32bit read(byte[], u32bit, u32bit);
-      u32bit peek(byte[], u32bit, u32bit, u32bit) const;
-      u32bit remaining(u32bit) const;
+      u32bit read(byte[], u32bit, Pipe::message_id);
+      u32bit peek(byte[], u32bit, u32bit, Pipe::message_id) const;
+      u32bit remaining(Pipe::message_id) const;
 
       void add(class SecureQueue*);
       void retire();
 
-      u32bit message_count() const;
+      Pipe::message_id message_count() const;
 
       Output_Buffers();
       ~Output_Buffers();
    private:
-      class SecureQueue* get(u32bit) const;
+      class SecureQueue* get(Pipe::message_id) const;
 
       std::deque<SecureQueue*> buffers;
-      u32bit offset;
+      Pipe::message_id offset;
    };
 
 }
diff --git a/include/pipe.h b/include/pipe.h
index 20fdc6a41..89f1ac4db 100644
--- a/include/pipe.h
+++ b/include/pipe.h
@@ -20,6 +20,12 @@ class Pipe : public DataSource
    public:
       typedef u32bit message_id;
 
+      class Invalid_Message_Number : public Invalid_Argument
+         {
+         public:
+            Invalid_Message_Number(const std::string&, message_id);
+         };
+
       static const message_id LAST_MESSAGE, DEFAULT_MESSAGE;
 
       void write(const byte[], u32bit);
@@ -48,7 +54,7 @@ class Pipe : public DataSource
 
       message_id default_msg() const { return default_read; }
       void set_default_msg(message_id);
-      u32bit message_count() const;
+      message_id message_count() const;
       bool end_of_data() const;
 
       void start_msg();
diff --git a/src/exceptn.cpp b/src/exceptn.cpp
index 07e6bb419..29357afa5 100644
--- a/src/exceptn.cpp
+++ b/src/exceptn.cpp
@@ -34,16 +34,6 @@ Invalid_IV_Length::Invalid_IV_Length(const std::string& mode, u32bit bad_len)
    }
 
 /*************************************************
-* Constructor for Invalid_Message_Number         *
-*************************************************/
-Invalid_Message_Number::Invalid_Message_Number(const std::string& where,
-                                               u32bit message_no)
-   {
-   set_msg("Pipe::" + where + ": Invalid message number " +
-           to_string(message_no));
-   }
-
-/*************************************************
 * Constructor for Algorithm_Not_Found            *
 *************************************************/
 Algorithm_Not_Found::Algorithm_Not_Found(const std::string& name)
diff --git a/src/out_buf.cpp b/src/out_buf.cpp
index 2586d65c2..392592705 100644
--- a/src/out_buf.cpp
+++ b/src/out_buf.cpp
@@ -11,7 +11,8 @@ namespace Botan {
 /*************************************************
 * Read data from a message                       *
 *************************************************/
-u32bit Output_Buffers::read(byte output[], u32bit length, u32bit msg)
+u32bit Output_Buffers::read(byte output[], u32bit length,
+                            Pipe::message_id msg)
    {
    SecureQueue* q = get(msg);
    if(q)
@@ -23,7 +24,8 @@ u32bit Output_Buffers::read(byte output[], u32bit length, u32bit msg)
 * Peek at data in a message                      *
 *************************************************/
 u32bit Output_Buffers::peek(byte output[], u32bit length,
-                            u32bit stream_offset, u32bit msg) const
+                            u32bit stream_offset,
+                            Pipe::message_id msg) const
    {
    SecureQueue* q = get(msg);
    if(q)
@@ -34,7 +36,7 @@ u32bit Output_Buffers::peek(byte output[], u32bit length,
 /*************************************************
 * Check available bytes in a message             *
 *************************************************/
-u32bit Output_Buffers::remaining(u32bit msg) const
+u32bit Output_Buffers::remaining(Pipe::message_id msg) const
    {
    SecureQueue* q = get(msg);
    if(q)
@@ -67,7 +69,7 @@ void Output_Buffers::retire()
          {
          delete buffers[0];
          buffers.pop_front();
-         ++offset;
+         offset = offset + Pipe::message_id(1);
          }
       else
          break;
@@ -77,7 +79,7 @@ void Output_Buffers::retire()
 /*************************************************
 * Get a particular output queue                  *
 *************************************************/
-SecureQueue* Output_Buffers::get(u32bit msg) const
+SecureQueue* Output_Buffers::get(Pipe::message_id msg) const
    {
    if(msg < offset)
       return 0;
@@ -90,9 +92,9 @@ SecureQueue* Output_Buffers::get(u32bit msg) const
 /*************************************************
 * Return the total number of messages            *
 *************************************************/
-u32bit Output_Buffers::message_count() const
+Pipe::message_id Output_Buffers::message_count() const
    {
-   return (buffers.size() + offset);
+   return (offset + buffers.size());
    }
 
 /*************************************************
diff --git a/src/pipe.cpp b/src/pipe.cpp
index b740e049d..228dc3a22 100644
--- a/src/pipe.cpp
+++ b/src/pipe.cpp
@@ -6,9 +6,20 @@
 #include <botan/pipe.h>
 #include <botan/out_buf.h>
 #include <botan/secqueue.h>
+#include <botan/parsing.h>
 
 namespace Botan {
 
+/*************************************************
+* Constructor for Invalid_Message_Number         *
+*************************************************/
+Pipe::Invalid_Message_Number::Invalid_Message_Number(const std::string& where,
+                                                     message_id msg)
+   {
+   set_msg("Pipe::" + where + ": Invalid message number " +
+           to_string(msg));
+   }
+
 namespace {
 
 /*************************************************
@@ -276,7 +287,7 @@ void Pipe::pop()
 /*************************************************
 * Return the number of messages in this Pipe     *
 *************************************************/
-u32bit Pipe::message_count() const
+Pipe::message_id Pipe::message_count() const
    {
    return outputs->message_count();
    }
@@ -284,7 +295,10 @@ u32bit Pipe::message_count() const
 /*************************************************
 * Static Member Variables                        *
 *************************************************/
-const Pipe::message_id Pipe::LAST_MESSAGE    = static_cast<Pipe::message_id>(-2);
-const Pipe::message_id Pipe::DEFAULT_MESSAGE = static_cast<Pipe::message_id>(-1);
+const Pipe::message_id Pipe::LAST_MESSAGE =
+   static_cast<Pipe::message_id>(-2);
+
+const Pipe::message_id Pipe::DEFAULT_MESSAGE =
+   static_cast<Pipe::message_id>(-1);
 
 }