reapi: add C++ API functionality

resource/reapi/bindings/c++/reapi.hpp

@@ -190,6 +190,21 @@ class reapi_t {
         return -1;
     }
 
+    /*! Update the resource state with R.
+     *
+     *  \param h         Opaque handle. How it is used is an implementation
+     *                   detail. However, when it is used within a Flux's
+     *                   service module, it is expected to be a pointer
+     *                   to a flux_t object.
+     *  \param R_subgraph R string of std::string.
+     *  \return          0 on success; -1 on error.
+     */
+    static int grow (void *h,
+                     const std::string &R_subgraph)
+    {
+        return -1;
+    }
+
     /*! Cancel the allocation or reservation corresponding to jobid.
      *
      *  \param h         Opaque handle. How it is used is an implementation

resource/reapi/bindings/c++/reapi_cli.hpp

@@ -89,6 +89,7 @@ class resource_query_t {
     void set_job (const uint64_t jobid, const std::shared_ptr<job_info_t> &job);
     int remove_job (const uint64_t jobid);
     int remove_job (const uint64_t jobid, const std::string &R, bool &full_removal);
+    int grow (const std::string &R_subgraph);
     void incr_job_counter ();
 
     /* Run the traverser to match the jobspec */
@@ -148,6 +149,7 @@ class reapi_cli_t : public reapi_t {
                                 int64_t &at,
                                 double &ov,
                                 std::string &R_out);
+    static int grow (void *h, const std::string &R_subgraph);
     static int cancel (void *h, const uint64_t jobid, bool noent_ok);
     static int cancel (void *h,
                        const uint64_t jobid,

resource/reapi/bindings/c++/reapi_cli_impl.hpp

@@ -165,6 +165,20 @@ int reapi_cli_t::update_allocate (void *h,
     return NOT_YET_IMPLEMENTED;
 }
 
+int reapi_cli_t::grow (void *h,
+                       const std::string &R_subgraph)
+{
+    resource_query_t *rq = static_cast<resource_query_t *> (h);
+    int rc = -1;
+
+    if ((rc = rq->grow (R_subgraph)) != 0) {
+        m_err_msg += __FUNCTION__;
+        m_err_msg += ": ERROR: grow error: " + std::string (strerror (errno)) + "\n";
+    }
+
+    return rc;
+}
+
 int reapi_cli_t::match_allocate_multi (void *h,
                                        bool orelse_reserve,
                                        const char *jobs,
@@ -722,6 +736,42 @@ int resource_query_t::remove_job (const uint64_t jobid, const std::string &R, bo
     return rc;
 }
 
+int resource_query_t::grow (const std::string &R_subgraph)
+{
+    int rc = -1;
+    std::shared_ptr<resource_reader_base_t> reader;
+    vtx_t v = boost::graph_traits<resource_graph_t>::null_vertex ();
+
+    if (R_subgraph == "") {
+        errno = EINVAL;
+        return rc;
+    }
+    if (params.load_format != "jgf") {
+        m_err_msg = __FUNCTION__;
+        m_err_msg += ": ERROR: growing a resource graph not ";
+        m_err_msg += " initialized with JGF is unsupported\n";
+        errno = ENOTSUP;
+        return rc;
+    }
+    if ((reader = create_resource_reader ("jgf")) == nullptr) {
+        m_err_msg = __FUNCTION__;
+        m_err_msg += ": ERROR: can't create JGF reader\n";
+        return rc;
+    }
+    if ((rc = reader->unpack_at (db->resource_graph, db->metadata, v, R_subgraph, -1)) != 0) {
+        m_err_msg = __FUNCTION__;
+        m_err_msg += ": ERROR: reader returned error: ";
+        m_err_msg += reader->err_message () + "\n";
+        return rc;
+    }
+    if ((rc = traverser->initialize (db, matcher)) != 0) {
+        m_err_msg = __FUNCTION__;
+        m_err_msg += ": ERROR: reinitialize traverser after grow. ";
+        m_err_msg += reader->err_message () + "\n";
+    }
+    return rc;
+}
+
 void resource_query_t::incr_job_counter ()
 {
     jobid_counter++;