Move to process v2

Boost process v2 brings some significant benefits to our launching of
processes[1].  In bmcweb terms:
1. The code is radically simpler, which decreaeses compile times, and
   reduces the scope for code scanning tools.
2. The code now uses standard asio pipes instead of inventing its own.
3. Separate compilation.

Tested:
We don't have a lot of unit tests for the virtual media stuff that I can
run, but we do have unit tests for credentials pipe, which in this
change have been ported over, so the feature works.  Unit tests are
passing.

[1] https://www.boost.org/doc/libs/1_80_0/doc/html/boost_process/v2.html#boost_process.v2.introduction
Change-Id: Ia20226819d75ff6e492f8852185f0b73e8f5cf83
Signed-off-by: Ed Tanous <ed@tanous.net>

2 files changed, 30 insertions, 17 deletions

diff --git a/include/credential_pipe.hpp b/include/credential_pipe.hpp
index 169d47c6cb..2cc3dc8b28 100644
--- a/include/credential_pipe.hpp
+++ b/include/credential_pipe.hpp
@@ -1,9 +1,13 @@
 #pragma once
 
+#include "logging.hpp"
+
 #include <boost/asio/buffer.hpp>
+#include <boost/asio/connect_pipe.hpp>
 #include <boost/asio/io_context.hpp>
+#include <boost/asio/readable_pipe.hpp>
+#include <boost/asio/writable_pipe.hpp>
 #include <boost/asio/write.hpp>
-#include <boost/process/async_pipe.hpp>
 
 #include <array>
 #include <string>
@@ -12,7 +16,15 @@
 class CredentialsPipe
 {
   public:
-    explicit CredentialsPipe(boost::asio::io_context& io) : impl(io) {}
+    explicit CredentialsPipe(boost::asio::io_context& io) : impl(io), read(io)
+    {
+        boost::system::error_code ec;
+        boost::asio::connect_pipe(read, impl, ec);
+        if (ec)
+        {
+            BMCWEB_LOG_CRITICAL("Failed to connect pipe {}", ec.what());
+        }
+    }
 
     CredentialsPipe(const CredentialsPipe&) = delete;
     CredentialsPipe(CredentialsPipe&&) = delete;
@@ -25,9 +37,9 @@ class CredentialsPipe
         explicit_bzero(pass.data(), pass.capacity());
     }
 
-    int fd() const
+    int releaseFd()
     {
-        return impl.native_source();
+        return read.release();
     }
 
     template <typename WriteHandler>
@@ -44,7 +56,8 @@ class CredentialsPipe
                                  std::forward<WriteHandler>(handler));
     }
 
-    boost::process::async_pipe impl;
+    boost::asio::writable_pipe impl;
+    boost::asio::readable_pipe read;
 
   private:
     std::string user;
diff --git a/include/vm_websocket.hpp b/include/vm_websocket.hpp
index 19054a6d97..3a72b3adb5 100644
--- a/include/vm_websocket.hpp
+++ b/include/vm_websocket.hpp
@@ -3,10 +3,11 @@
 #include "app.hpp"
 #include "websocket.hpp"
 
+#include <boost/asio/readable_pipe.hpp>
+#include <boost/asio/writable_pipe.hpp>
 #include <boost/beast/core/flat_static_buffer.hpp>
-#include <boost/process/async_pipe.hpp>
-#include <boost/process/child.hpp>
-#include <boost/process/io.hpp>
+#include <boost/process/v2/process.hpp>
+#include <boost/process/v2/stdio.hpp>
 
 #include <csignal>
 
@@ -26,8 +27,11 @@ static constexpr auto nbdBufferSize = (128 * 1024 + 16) * 4;
 class Handler : public std::enable_shared_from_this<Handler>
 {
   public:
-    Handler(const std::string& mediaIn, boost::asio::io_context& ios) :
-        pipeOut(ios), pipeIn(ios), media(mediaIn),
+    Handler(const std::string& media, boost::asio::io_context& ios) :
+        pipeOut(ios), pipeIn(ios),
+        proxy(ios, "/usr/bin/nbd-proxy", {media},
+              boost::process::v2::process_stdio{
+                  .in = pipeIn, .out = pipeOut, .err = nullptr}),
         outputBuffer(new boost::beast::flat_static_buffer<nbdBufferSize>),
         inputBuffer(new boost::beast::flat_static_buffer<nbdBufferSize>)
     {}
@@ -56,9 +60,6 @@ class Handler : public std::enable_shared_from_this<Handler>
     void connect()
     {
         std::error_code ec;
-        proxy = boost::process::child("/usr/bin/nbd-proxy", media,
-                                      boost::process::std_out > pipeOut,
-                                      boost::process::std_in < pipeIn, ec);
         if (ec)
         {
             BMCWEB_LOG_ERROR("Couldn't connect to nbd-proxy: {}", ec.message());
@@ -148,10 +149,9 @@ class Handler : public std::enable_shared_from_this<Handler>
         });
     }
 
-    boost::process::async_pipe pipeOut;
-    boost::process::async_pipe pipeIn;
-    boost::process::child proxy;
-    std::string media;
+    boost::asio::readable_pipe pipeOut;
+    boost::asio::writable_pipe pipeIn;
+    boost::process::v2::process proxy;
     bool doingWrite{false};
 
     std::unique_ptr<boost::beast::flat_static_buffer<nbdBufferSize>>