refactor code to make better use of std::string and simplify using changes to Variable class API

src/KIM/kim_init.cpp

@@ -420,51 +420,45 @@ void KimInit::do_init(char *model_name, char *user_units, char *model_units, KIM
 
 /* ---------------------------------------------------------------------- */
 
-void KimInit::do_variables(char *user_units, char *model_units)
+void KimInit::do_variables(const std::string &from, const std::string &to)
 {
-  char *from = user_units, *to = model_units;
-  Variable *variable = input->variable;
-
   // refuse conversion from or to reduced units
 
-  if ((strcmp(from,"lj") == 0) || (strcmp(to,"lj") == 0))
+  if ((from == "lj") || (to == "lj"))
     error->all(FLERR,"Cannot set up conversion variables for 'lj' units");
 
   // get index to internal style variables. create, if needed.
   // set conversion factors for newly created variables.
   double conversion_factor;
   int ier;
-  char *args[3];
   std::string var_str;
-  args[1] = (char *)"internal";
-  args[2] = (char *)"1.0";
   int v_unit;
-  int const nunits = 14;
+  const char *units[] = {"mass",
-  char *units[nunits] = {(char *)"mass",
+                         "distance",
-                         (char *)"distance",
+                         "time",
-                         (char *)"time",
+                         "energy",
-                         (char *)"energy",
+                         "velocity",
-                         (char *)"velocity",
+                         "force",
-                         (char *)"force",
+                         "torque",
-                         (char *)"torque",
+                         "temperature",
-                         (char *)"temperature",
+                         "pressure",
-                         (char *)"pressure",
+                         "viscosity",
-                         (char *)"viscosity",
+                         "charge",
-                         (char *)"charge",
+                         "dipole",
-                         (char *)"dipole",
+                         "efield",
-                         (char *)"efield",
+                         "density",
-                         (char *)"density"};
+                         nullptr};
 
   input->write_echo(fmt::format("# Conversion factors from {} to {}:\n",
                                 from,to));
 
-  for (int i = 0; i < nunits; ++i) {
+  auto variable = input->variable;
-    var_str = std::string("_u_") + std::string(units[i]);
+  for (int i = 0; units[i] != nullptr; ++i) {
-    args[0] = (char *)var_str.c_str();
+    var_str = std::string("_u_") + units[i];
-    v_unit = variable->find(args[0]);
+    v_unit = variable->find(var_str.c_str());
     if (v_unit < 0) {
-      variable->set(3,args);
+      variable->set(var_str + " internal 1.0");
-      v_unit = variable->find(args[0]);
+      v_unit = variable->find(var_str.c_str());
     }
     ier = lammps_unit_conversion(units[i],
                                  from,

src/KIM/kim_init.h

@@ -85,7 +85,7 @@ class KimInit : protected Pointers {
   void determine_model_type_and_units(char *, char *, char **, KIM_Model *&);
   void write_log_cite(char *);
   void do_init(char *, char *, char *, KIM_Model *&);
-  void do_variables(char*, char*);
+  void do_variables(const std::string &, const std::string &);
 };
 
 }

src/KIM/kim_property.cpp

@@ -111,12 +111,7 @@ void kimProperty::command(int narg, char **arg)
 
   // Get the kim_str ptr to the data associated with a kim_property_str
   // variable
-  char *kim_str =
+  char *kim_str = input->variable->retrieve("kim_property_str");
-    input->variable->retrieve(const_cast<char *>("kim_property_str"));
-
-  char **kim_str_cmd = new char *[3];
-  kim_str_cmd[0] = const_cast<char *>("kim_property_str");
-
   PyGILState_STATE gstate = PyGILState_Ensure();
 
   // kim_property module
@@ -203,15 +198,8 @@ void kimProperty::command(int narg, char **arg)
 
     // Python function returned a string value
     const char *pystr = PyUnicode_AsUTF8(pValue);
-
+    if (kim_str) input->variable->set_string("kim_property_str", pystr);
-    kim_str_cmd[2] = const_cast<char *>(pystr);
+    else input->variable->set(std::string("kim_property_str string ") + pystr);
-
-    if (kim_str) {
-      input->variable->set_string(kim_str_cmd[0], kim_str_cmd[2]);
-    } else {
-      kim_str_cmd[1] = const_cast<char *>("string");
-      input->variable->set(3, kim_str_cmd);
-    }
 
     Py_XDECREF(pArgs);
     Py_XDECREF(pFunc);
@@ -268,10 +256,7 @@ void kimProperty::command(int narg, char **arg)
 
     // Python function returned a string value
     const char *pystr = PyUnicode_AsUTF8(pValue);
-
+    input->variable->set_string("kim_property_str", pystr);
-    kim_str_cmd[2] = const_cast<char *>(pystr);
-
-    input->variable->set_string(kim_str_cmd[0], kim_str_cmd[2]);
 
     Py_XDECREF(pArgs);
     Py_XDECREF(pFunc);
@@ -335,10 +320,7 @@ void kimProperty::command(int narg, char **arg)
 
     // Python function returned a string value
     const char *pystr = PyUnicode_AsUTF8(pValue);
-
+    input->variable->set_string("kim_property_str", pystr);
-    kim_str_cmd[2] = const_cast<char *>(pystr);
-
-    input->variable->set_string(kim_str_cmd[0], kim_str_cmd[2]);
 
     Py_XDECREF(pArgs);
     Py_XDECREF(pFunc);
@@ -402,10 +384,7 @@ void kimProperty::command(int narg, char **arg)
 
     // Python function returned a string value
     const char *pystr = PyUnicode_AsUTF8(pValue);
-
+    input->variable->set_string("kim_property_str", pystr);
-    kim_str_cmd[2] = const_cast<char *>(pystr);
-
-    input->variable->set_string(kim_str_cmd[0], kim_str_cmd[2]);
 
     Py_XDECREF(pArgs);
     Py_XDECREF(pFunc);
@@ -464,8 +443,7 @@ void kimProperty::command(int narg, char **arg)
       pValue = NULL;
 
     // Destroy the variable
-    kim_str_cmd[1] = const_cast<char *>("delete");
+    input->variable->set("kim_property_str delete");
-    input->variable->set(2, kim_str_cmd);
 
     Py_XDECREF(pArgs);
     Py_XDECREF(pFunc);
@@ -474,7 +452,6 @@ void kimProperty::command(int narg, char **arg)
 
   PyGILState_Release(gstate);
 
-  delete[] kim_str_cmd;
 #endif // PY_MAJOR_VERSION
 #endif // LMP_PYTHON
 }

src/KIM/kim_units.h

@@ -52,8 +52,13 @@
 /* ----------------------------------------------------------------------
    Designed for use with the kim-api-2.0.2 (and newer) package
 ------------------------------------------------------------------------- */
+#ifndef LMP_KIM_UNITS_H
+#define LMP_KIM_UNITS_H
+
+#include <string>
 
 int lammps_unit_conversion(const std::string &unit_type_str,
                            const std::string &from_system_str,
                            const std::string &to_system_str,
                            double &conversion_factor);
+#endif

src/variable.cpp

@@ -578,13 +578,14 @@ void Variable::set(char *name, int narg, char **arg)
    called via library interface, so external programs can set variables
 ------------------------------------------------------------------------- */
 
-int Variable::set_string(char *name, char *str)
+int Variable::set_string(const char *name, const char *str)
 {
   int ivar = find(name);
   if (ivar < 0) return -1;
   if (style[ivar] != STRING) return -1;
   delete [] data[ivar][0];
-  copy(1,&str,data[ivar]);
+  data[ivar][0] = new char[strlen(str)+1];
+  strcpy(data[ivar][0],str);
   return 0;
 }
 

src/variable.h

@@ -24,10 +24,10 @@ class Variable : protected Pointers {
  public:
   Variable(class LAMMPS *);
   ~Variable();
-  void set(const std::string &);
   void set(int, char **);
+  void set(const std::string &);
   void set(char *, int, char **);
-  int set_string(char *, char *);
+  int set_string(const char *, const char *);
   int next(int, char **);
 
   int find(const char *);