allow to specify name for custom_solver as additional arg for Algorit…

…hmBuilder

- if not empty, will be used in "This is Ipopt ..." message

ChangeLog.md

@@ -14,6 +14,7 @@ More detailed information about incremental changes can be found in the
 - Fixed crash of GetIpoptCurrentIterate() and GetIpoptCurrentViolations() in
   C interface when called before or after IpoptSolve(). [#644, #645, by Robbybp]
 - Fixed crash when trying to solve problem without variables and constraints. [#648]
+- Added optional argument to `AlgorithmBuilder` constructor to provide name of custom solver. [#618]
 
 ### 3.14.11 (2023-02-07)
 

src/Algorithm/IpAlgBuilder.cpp

@@ -80,9 +80,11 @@ static const Index dbg_verbosity = 0;
 #endif
 
 AlgorithmBuilder::AlgorithmBuilder(
-   SmartPtr<AugSystemSolver> custom_solver /*=NULL*/
+   SmartPtr<AugSystemSolver> custom_solver, /*=NULL*/
+   const std::string& custom_solver_name    /*=std::string()*/
 )
-   : custom_solver_(custom_solver)
+   : custom_solver_(custom_solver),
+     custom_solver_name_(custom_solver_name)
 { }
 
 void AlgorithmBuilder::RegisterOptions(
@@ -576,6 +578,8 @@ SmartPtr<AugSystemSolver> AlgorithmBuilder::AugSystemSolverFactory(
    {
       ASSERT_EXCEPTION(IsValid(custom_solver_), OPTION_INVALID, "Selected linear solver CUSTOM not available.");
       AugSolver = custom_solver_;
+      if( !custom_solver_name_.empty() )
+         linear_solver = custom_solver_name_;
    }
    else
    {

src/Algorithm/IpAlgBuilder.hpp

@@ -53,7 +53,8 @@ class IPOPTLIB_EXPORT AlgorithmBuilder: public ReferencedObject
    ///@{
    /** Constructor */
    AlgorithmBuilder(
-      SmartPtr<AugSystemSolver> custom_solver = NULL
+      SmartPtr<AugSystemSolver> custom_solver = NULL,
+      const std::string& custom_solver_name   = std::string()   /**< @since 3.14.12 */
    );
 
    /** Destructor */
@@ -402,6 +403,7 @@ class IPOPTLIB_EXPORT AlgorithmBuilder: public ReferencedObject
    /** Optional pointer to AugSystemSolver.  If this is set in the
     *  constructor, we will use this to solve the linear systems. */
    SmartPtr<AugSystemSolver> custom_solver_;
+   std::string custom_solver_name_;
 
    /// name of linear solver constructed in SymLinearSolverFactory
    std::string linear_solver;