Start NLWriter C API #30

nl-writer2/CMakeLists.txt

@@ -12,58 +12,98 @@ option(NLW2_LIB_ORIG_HDR
 
 
 set(NLW2_DIR ${CMAKE_CURRENT_SOURCE_DIR})
+set(NLW2_INCLUDE_PATH ${NLW2_DIR}/include)
+set(NLW2_SRC_PATH     ${NLW2_DIR}/src)
+set(NLW2_EXAMPLE_PATH ${NLW2_DIR}/examples)
+
+# NLW2 library C++ sources
 set(NLW2_LIB_FILES
-        ${NLW2_DIR}/src/nl-writer2.cc
-        ${NLW2_DIR}/src/nl-utils2.cc
-        ${NLW2_DIR}/src/dtoa.c)
+        ${NLW2_SRC_PATH}/nl-writer2.cc
+        ${NLW2_SRC_PATH}/nl-utils2.cc
+        ${NLW2_SRC_PATH}/dtoa.c)
 set(NLW2_INC_FILES
-              ${NLW2_DIR}/include/mp/nlsol.h
-              ${NLW2_DIR}/include/mp/nl-header.h
-              ${NLW2_DIR}/include/mp/nl-feeder2.h
-              ${NLW2_DIR}/include/mp/nl-writer2.h
-              ${NLW2_DIR}/include/mp/nl-writer2.hpp
-              ${NLW2_DIR}/include/mp/nl-writer2-misc.h
-              ${NLW2_DIR}/include/mp/nl-utils2.h
-              ${NLW2_DIR}/include/mp/sol-reader2.h
-              ${NLW2_DIR}/include/mp/sol-reader2.hpp
-              ${NLW2_DIR}/include/mp/sol-handler2.h
+              ${NLW2_INCLUDE_PATH}/mp/nlsol.h
+              ${NLW2_INCLUDE_PATH}/mp/nl-header.h
+              ${NLW2_INCLUDE_PATH}/mp/nl-feeder2.h
+              ${NLW2_INCLUDE_PATH}/mp/nl-writer2.h
+              ${NLW2_INCLUDE_PATH}/mp/nl-writer2.hpp
+              ${NLW2_INCLUDE_PATH}/mp/nl-writer2-misc.h
+              ${NLW2_INCLUDE_PATH}/mp/nl-utils2.h
+              ${NLW2_INCLUDE_PATH}/mp/sol-reader2.h
+              ${NLW2_INCLUDE_PATH}/mp/sol-reader2.hpp
+              ${NLW2_INCLUDE_PATH}/mp/sol-handler2.h
               )
 
-# Create library
+# Create C++ library
 set(NLW2_LIB_NAME "nlw2")
 add_library(${NLW2_LIB_NAME} STATIC
   ${NLW2_LIB_FILES} ${NLW2_INC_FILES})
 target_include_directories(
-	${NLW2_LIB_NAME} PUBLIC ${NLW2_DIR}/include)
+  ${NLW2_LIB_NAME} PUBLIC ${NLW2_INCLUDE_PATH})
 if (NLW2_LIB_ORIG_HDR)
 	message(STATUS
 		"   NLW2_LIB: Building with the original NL header comments")
 	target_compile_definitions(
 		${NLW2_LIB_NAME} PUBLIC NL_LIB2_ORIG_HDR)
 endif()
 
-# NLW2 example
-set(NLSOL_EX_FILES
-  ${NLW2_DIR}/examples/nlsol_ex.cc
-  ${NLW2_DIR}/examples/nlsol_ex_mdl.h
-  ${NLW2_DIR}/examples/nlsol_ex_nl.h
-  ${NLW2_DIR}/examples/nlsol_ex_sol.h)
+# C API sources
+set(NLW2_C_API_LIB_FILES
+        ${NLW2_DIR}/src/c_api.cc
+        )
+set(NLW2_C_API_INC_FILES
+              ${NLW2_INCLUDE_PATH}/api/c/nl-feeder2.h
+              )
+
+# C API library
+set(NLW2_C_API_LIB_NAME "nlw2_c_api")
+add_library(${NLW2_C_API_LIB_NAME} STATIC
+  ${NLW2_C_API_LIB_FILES} ${NLW2_C_API_INC_FILES})
+target_include_directories(
+  ${NLW2_C_API_LIB_NAME} PUBLIC ${NLW2_INCLUDE_PATH})
+
+######################################################
+# Examples
+
+# NLW2 C++ example
+set(NLW2_CPP_EXAMPLE_PATH ${NLW2_EXAMPLE_PATH}/cpp)
+set(NLSOL_CPP_EX_FILES
+  ${NLW2_CPP_EXAMPLE_PATH}/nlsol_ex.cc
+  ${NLW2_CPP_EXAMPLE_PATH}/nlsol_ex_mdl.h
+  ${NLW2_CPP_EXAMPLE_PATH}/nlsol_ex_nl.h
+  ${NLW2_CPP_EXAMPLE_PATH}/nlsol_ex_sol.h)
+
+# NLW2 C API example
+set(NLW2_C_EXAMPLE_PATH ${NLW2_EXAMPLE_PATH}/c)
+set(NLSOL_C_EX_FILES
+  ${NLW2_C_EXAMPLE_PATH}/nlsol_ex_c.c
+  )
 
 option(BUILD_EXAMPLES_NLW2
   "Build NLW2 examples (library not affected). Assumes nl-opcodes.h (generated by MP)"
   ON)
 if (BUILD_EXAMPLES_NLW2)         # Actually build the example
-  add_executable(nl-writer-example ${NLSOL_EX_FILES})
-  target_include_directories(nl-writer-example PUBLIC
-    ${NLW2_DIR}/include)
-  target_link_libraries(nl-writer-example ${NLW2_LIB_NAME})
+  add_executable(nl-writer-example-cpp ${NLSOL_CPP_EX_FILES})
+  target_include_directories(nl-writer-example-cpp PUBLIC
+    ${NLW2_INCLUDE_PATH})
+  target_link_libraries(nl-writer-example-cpp ${NLW2_LIB_NAME})
+
+  add_executable(nl-writer-example-c ${NLSOL_C_EX_FILES})
+  target_include_directories(nl-writer-example-c PUBLIC
+    ${NLW2_INCLUDE_PATH})
+  target_link_libraries(nl-writer-example-c ${NLW2__C_API_LIB_NAME})
 endif()
 
+
+##################################################################
 # Export library include path
-set(NLW2_INCLUDE_PATH ${NLW2_DIR}/include PARENT_SCOPE)
+set(NLW2_INCLUDE_PATH ${NLW2_INCLUDE_PATH} PARENT_SCOPE)
 # Export source files
 set(NLW2_SRC
-  ${NLW2_LIB_FILES} ${NLW2_INC_FILES} ${NLSOL_EX_FILES}
+  ${NLW2_LIB_FILES} ${NLW2_INC_FILES} ${NLSOL_CPP_EX_FILES}
+  ${NLW2_C_API_LIB_FILES} ${NLW2_C_API_INC_FILES}
+    ${NLSOL_C_EX_FILES}
   PARENT_SCOPE)
-# Export library target name
+# Export library target names
 set(NLW2_LIB_NAME ${NLW2_LIB_NAME} PARENT_SCOPE)
+set(NLW2_C_API_LIB_NAME ${NLW2_C_API_LIB_NAME} PARENT_SCOPE)

nl-writer2/examples/c/nlsol_ex_c.c

@@ -0,0 +1,36 @@
+/**
+ * C API example using NLWriter2 and SOLReader2
+ * to write NL file, execute solver, and read SOL file.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "api/c/nl-feeder2.h"
+
+#include "nlsol_ex_c_model.h"
+
+int main(int argc, const char* const* argv) {
+  if (argc<2) {
+    printf("%s\n",
+           "AMPL NL writer C API example.\n"
+           "Usage:\n"
+           "  <this_exe> <solver> [\"<solver_options>\" [binary/text [<stub>]]],\n\n"
+           "where <solver> is ipopt, gurobi, minos, ...;\n"
+           "binary/text is the NL format (default: binary.)\n"
+           "Examples:\n"
+           "  <this_exe> highs \"\" text /tmp/stub\n"
+           "  <this_exe> gurobi \"mip:return_gap=1\"");
+    exit(0);
+  }
+
+  const char* solver = (argc>1) ? argv[1] : "highs";
+  const char* sopts = (argc>2) ? argv[2] : "";
+  int binary = (argc<=3) || strcmp("text", argv[3]);
+  const char* stub = (argc>4) ? argv[4] : "stub";
+
+
+  return 0;
+}

nl-writer2/examples/c/nlsol_ex_c_model.h

@@ -0,0 +1,41 @@
+#ifndef NLSOL_EX_C_MODEL_H
+#define NLSOL_EX_C_MODEL_H
+
+// #include "api/c/nl-header.h"
+//#include "mp/nl-opcodes.h"
+
+/**
+ * A linear model for NL Writer C API example.
+ * Illustrates NL variable order (continuous -> integer),
+ * linear constraints.
+ *
+
+## In AMPL, set option presolve 0; to reproduce
+##
+## To write NL file and name files in AMPL, use commands
+##    ampl: option nl_comments 1;
+##    ampl: option auxfiles rc;
+##    ampl: write gmodel;
+
+var x >=0, integer;
+var y >=-17, <=504;
+maximize TotalSum:
+    x + 13*y;
+subj to C2:
+       3700*x + 0.6*y <= 3e4;
+subj to C3:
+       22*x + 14536*y <= 3e5;
+
+## Initial guess
+let x := 1.5;
+let y := 0.11;
+
+## A suffix
+suffix zork;
+let C2.zork := 5;
+
+ *
+ */
+
+
+#endif // NLSOL_EX_C_MODEL_H

nl-writer2/include/api/c/nl-feeder2.h

@@ -0,0 +1,18 @@
+/**
+ * C API: extern "C" wrapper for the NLFeeder2 interface
+ *
+ */
+
+#ifndef NLFEEDER2_H
+#define NLFEEDER2_H
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
+#endif // NLFEEDER2_H

nl-writer2/src/c_api.cc

@@ -0,0 +1,6 @@
+/**
+ * C API implementation
+ *
+ */
+
+#include "api/c/nl-feeder2.h"