Use a special typedef, Pipe::message_id, rather than a bare u32bit,

to represent the message number in a Pipe

3 files changed, 25 insertions, 23 deletions

diff --git a/include/pipe.h b/include/pipe.h
index 9bc98a72b..9bf05b76a 100644
--- a/include/pipe.h
+++ b/include/pipe.h
@@ -18,7 +18,9 @@ namespace Botan {
 class Pipe : public DataSource
    {
    public:
-      static const u32bit LAST_MESSAGE, DEFAULT_MESSAGE;
+      typedef u32bit message_id;
+
+      static const message_id LAST_MESSAGE, DEFAULT_MESSAGE;
 
       void write(const byte[], u32bit);
       void write(const MemoryRegion<byte>&);
@@ -31,21 +33,21 @@ class Pipe : public DataSource
       void process_msg(const std::string&);
       void process_msg(DataSource&);
 
-      u32bit remaining(u32bit = DEFAULT_MESSAGE) const;
+      u32bit remaining(message_id = DEFAULT_MESSAGE) const;
 
       u32bit read(byte[], u32bit);
-      u32bit read(byte[], u32bit, u32bit);
-      u32bit read(byte&, u32bit = DEFAULT_MESSAGE);
+      u32bit read(byte[], u32bit, message_id);
+      u32bit read(byte&, message_id = DEFAULT_MESSAGE);
 
-      SecureVector<byte> read_all(u32bit = DEFAULT_MESSAGE);
-      std::string read_all_as_string(u32bit = DEFAULT_MESSAGE);
+      SecureVector<byte> read_all(message_id = DEFAULT_MESSAGE);
+      std::string read_all_as_string(message_id = DEFAULT_MESSAGE);
 
       u32bit peek(byte[], u32bit, u32bit) const;
-      u32bit peek(byte[], u32bit, u32bit, u32bit) const;
-      u32bit peek(byte&, u32bit, u32bit = DEFAULT_MESSAGE) const;
+      u32bit peek(byte[], u32bit, u32bit, message_id) const;
+      u32bit peek(byte&, u32bit, message_id = DEFAULT_MESSAGE) const;
 
-      u32bit default_msg() const { return default_read; }
-      void set_default_msg(u32bit);
+      message_id default_msg() const { return default_read; }
+      void set_default_msg(message_id);
       u32bit message_count() const;
       bool end_of_data() const;
 
@@ -68,11 +70,11 @@ class Pipe : public DataSource
       void find_endpoints(Filter*);
       void clear_endpoints(Filter*);
 
-      u32bit get_message_no(const std::string&, u32bit) const;
+      message_id get_message_no(const std::string&, message_id) const;
 
       Filter* pipe;
       class Output_Buffers* outputs;
-      u32bit default_read;
+      message_id default_read;
       bool inside_msg;
    };
 
diff --git a/src/pipe.cpp b/src/pipe.cpp
index f821a9ffe..a19cff258 100644
--- a/src/pipe.cpp
+++ b/src/pipe.cpp
@@ -100,7 +100,7 @@ bool Pipe::end_of_data() const
 /*************************************************
 * Set the default read message                   *
 *************************************************/
-void Pipe::set_default_msg(u32bit msg)
+void Pipe::set_default_msg(message_id msg)
    {
    if(msg >= message_count())
       throw Invalid_Argument("Pipe::set_default_msg: msg number is too high");
@@ -284,7 +284,7 @@ u32bit Pipe::message_count() const
 /*************************************************
 * Static Member Variables                        *
 *************************************************/
-const u32bit Pipe::LAST_MESSAGE    = 0xFFFFFFFE;
-const u32bit Pipe::DEFAULT_MESSAGE = 0xFFFFFFFF;
+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);
 
 }
diff --git a/src/pipe_rw.cpp b/src/pipe_rw.cpp
index 1fa195210..617129b9f 100644
--- a/src/pipe_rw.cpp
+++ b/src/pipe_rw.cpp
@@ -12,7 +12,7 @@ namespace Botan {
 /*************************************************
 * Look up the canonical ID for a queue           *
 *************************************************/
-u32bit Pipe::get_message_no(const std::string& func_name, u32bit msg) const
+Pipe::message_id Pipe::get_message_no(const std::string& func_name, message_id msg) const
    {
    if(msg == DEFAULT_MESSAGE)
       msg = default_msg();
@@ -75,7 +75,7 @@ void Pipe::write(DataSource& source)
 /*************************************************
 * Read some data from the pipe                   *
 *************************************************/
-u32bit Pipe::read(byte output[], u32bit length, u32bit msg)
+u32bit Pipe::read(byte output[], u32bit length, message_id msg)
    {
    return outputs->read(output, length, get_message_no("read", msg));
    }
@@ -91,7 +91,7 @@ u32bit Pipe::read(byte output[], u32bit length)
 /*************************************************
 * Read a single byte from the pipe               *
 *************************************************/
-u32bit Pipe::read(byte& out, u32bit msg)
+u32bit Pipe::read(byte& out, message_id msg)
    {
    return read(&out, 1, msg);
    }
@@ -99,7 +99,7 @@ u32bit Pipe::read(byte& out, u32bit msg)
 /*************************************************
 * Return all data in the pipe                    *
 *************************************************/
-SecureVector<byte> Pipe::read_all(u32bit msg)
+SecureVector<byte> Pipe::read_all(message_id msg)
    {
    msg = ((msg != DEFAULT_MESSAGE) ? msg : default_msg());
    SecureVector<byte> buffer(remaining(msg));
@@ -110,7 +110,7 @@ SecureVector<byte> Pipe::read_all(u32bit msg)
 /*************************************************
 * Return all data in the pipe as a string        *
 *************************************************/
-std::string Pipe::read_all_as_string(u32bit msg)
+std::string Pipe::read_all_as_string(message_id msg)
    {
    msg = ((msg != DEFAULT_MESSAGE) ? msg : default_msg());
    SecureVector<byte> buffer(DEFAULT_BUFFERSIZE);
@@ -131,7 +131,7 @@ std::string Pipe::read_all_as_string(u32bit msg)
 /*************************************************
 * Find out how many bytes are ready to read      *
 *************************************************/
-u32bit Pipe::remaining(u32bit msg) const
+u32bit Pipe::remaining(message_id msg) const
    {
    return outputs->remaining(get_message_no("remaining", msg));
    }
@@ -140,7 +140,7 @@ u32bit Pipe::remaining(u32bit msg) const
 * Peek at some data in the pipe                  *
 *************************************************/
 u32bit Pipe::peek(byte output[], u32bit length,
-                  u32bit offset, u32bit msg) const
+                  u32bit offset, message_id msg) const
    {
    return outputs->peek(output, length, offset, get_message_no("peek", msg));
    }
@@ -156,7 +156,7 @@ u32bit Pipe::peek(byte output[], u32bit length, u32bit offset) const
 /*************************************************
 * Peek at a byte in the pipe                     *
 *************************************************/
-u32bit Pipe::peek(byte& out, u32bit offset, u32bit msg) const
+u32bit Pipe::peek(byte& out, u32bit offset, message_id msg) const
    {
    return peek(&out, 1, offset, msg);
    }