Merge pull request #178 from ampl/ortools

Merge preliminary ortools driver

solvers/CMakeLists.txt

@@ -233,6 +233,10 @@ add_ampl_backend(copt DLL_RUNTIME SHARED_LIB MODULE COPT LIBRARIES ${COPT_LIBS}
 add_ampl_backend(highsdirect DLL_RUNTIME SHARED_LIB
   MODULE HIGHS LIBRARIES ${HIGHS_LIBS} ${CMAKE_DL_LIBS})
 
+
+add_ampl_backend(ortoolsmp DLL_RUNTIME SHARED_LIB
+  MODULE ortoolsmp LIBRARIES ${ortoolsmp_LIBS} ${CMAKE_DL_LIBS})
+
 ## TODO Cannot use 'add_ampl_backend' because of the -direct name suffix
 add_ampl_solver(cplexdirect DLL_RUNTIME SHARED_LIB MODULE CPLEX
   cplex-ampls-c-api.h

solvers/ortoolsmp/CHANGES.ortoolsmp.md

@@ -0,0 +1,5 @@
+Summary of recent updates to ORTOOLS for AMPL
+=============================================
+
+### 20220420
+- First release of mock driver

solvers/ortoolsmp/README.ortoolsmp.txt

@@ -0,0 +1,5 @@
+ortools tutorial driver
+=======================
+
+The solver "ortools" is a mock solver, provided as an example - and as a template -
+on how to getting started using mp with FlatAPI to develop an mp-based solver interface.

solvers/ortoolsmp/main.cc

@@ -0,0 +1,10 @@
+#include "mp/backend-app.h"
+#include "ortoolsmpbackend.h"
+
+/// Declare a backend factory
+std::unique_ptr<mp::BasicBackend> CreateOrtoolsBackend();
+
+int main(int, char** argv) {
+  return
+    mp::RunBackendApp(argv, CreateOrtoolsBackend);
+}

solvers/ortoolsmp/model-mgr-with-std-pb.cc

@@ -0,0 +1,8 @@
+/**
+ * Generate ModelManagerWithPB<mp::Problem>
+ *
+ * Having a separate .cc should improve compilation speed
+ */
+
+#include "mp/model-mgr-with-std-pb.hpp"
+

solvers/ortoolsmp/ortoolsmp-ampls-c-api.h

@@ -0,0 +1,29 @@
+#ifndef ORTOOLSAMPLSCAPI_H
+#define ORTOOLSAMPLSCAPI_H
+/*
+ * C API for MP/Ortools
+ */
+
+#include "mp/ampls-c-api.h"
+
+/*
+ * Below are Ortools-specific AMPLS API functions.
+ * They complement the 'public' AMPLS API defined in ampls-c-api.h.
+ */
+
+/// Initialize AMPLS ortools.
+/// @param slv: pointer to struct AMPLS_MP_Solver to be populated.
+/// @param slv_opt: a string of solver options
+/// (normally provided in the <solver>_options string).
+/// Can be NULL.
+/// @return 0 on success, otherwise see slv->warnings_and_or_errors_
+int AMPLSOpenOrtools(AMPLS_MP_Solver* slv, const char* slv_opt);
+
+/// Shut down solver instance
+void AMPLSCloseOrtools(AMPLS_MP_Solver* slv);
+
+/// Extract the Ortools model handle
+void* GetOrtoolsmodel(AMPLS_MP_Solver* slv);
+
+
+#endif // ORTOOLSAMPLSCAPI_H

solvers/ortoolsmp/ortoolsmp-lib.c

@@ -0,0 +1,27 @@
+#include "ortoolsmp-ampls-c-api.h"
+
+#ifdef _WIN32
+#define APIEXPORT __declspec(dllexport)
+#else
+#define APIEXPORT  __attribute__((visibility("default")))
+#endif
+
+APIEXPORT void* AMPLloadmodel(int argc, char** argv, void* slvout) {
+  const char* nl_filename = argv[1];
+  const char *slv_opt= argv[2];
+  AMPLS_MP_Solver slv;
+  int ret = -1;
+  ret = AMPLSOpenOrtools(&slv, slv_opt);
+  ret = AMPLSLoadNLModel(&slv, nl_filename);
+  void* mdl = GetOrtoolsmodel(&slv);
+  slvout = &slv;
+  return mdl;
+}
+
+APIEXPORT void AMPLwritesolution(AMPLS_MP_Solver* slv) {
+  AMPLSReportResults(&slv);
+}
+
+APIEXPORT void AMPLclosesolver(AMPLS_MP_Solver* slv) {
+  AMPLSCloseOrtools(&slv);
+}