ArgInfo class for simpler parsing of compute, fix, variable references

src/arg_info.cpp

@@ -0,0 +1,74 @@
+/* ----------------------------------------------------------------------
+   LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
+   https://lammps.sandia.gov/, Sandia National Laboratories
+   Steve Plimpton, sjplimp@sandia.gov
+
+   Copyright (2003) Sandia Corporation.  Under the terms of Contract
+   DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
+   certain rights in this software.  This software is distributed under
+   the GNU General Public License.
+
+   See the README file in the top-level LAMMPS directory.
+------------------------------------------------------------------------- */
+
+#include "arg_info.h"
+
+#include <stdexcept>
+#include <cstring>
+
+using namespace LAMMPS_NS;
+
+ArgInfo::ArgInfo(const std::string &arg, int allowed)
+  : type(NONE), dim(0), index1(-1), index2(-1)
+{
+  if ((arg.size() > 2) && (arg[1] == '_')) {
+    if ((arg[0] == 'c') && (allowed & COMPUTE))  type = COMPUTE;
+    else if ((arg[0] == 'f') && (allowed & FIX)) type = FIX;
+    else if ((arg[0] == 'v') && (allowed & VARIABLE)) type = VARIABLE;
+    else {
+      name = arg;
+      return;
+    }
+
+    std::size_t has_idx1 = arg.find('[',2);
+    if (has_idx1 != std::string::npos) {
+      name = arg.substr(2,has_idx1-2);
+      dim = 1;
+
+      std::size_t has_idx2 = arg.find('[',has_idx1+1);
+      if (has_idx2 != std::string::npos) {
+        dim = 2;
+
+        if (arg[arg.size()-1] != ']') {
+          type = UNKNOWN;
+        } else {
+          try {
+            index2 = std::stoi(arg.substr(has_idx2+1,arg.size()-(has_idx2+2)));
+          } catch (std::invalid_argument &) {
+            type = UNKNOWN;
+          }
+        }
+      } else has_idx2 = arg.size();
+
+      if (arg[has_idx2-1] != ']') {
+        type = UNKNOWN;
+      } else {
+        try {
+          index1 = std::stoi(arg.substr(has_idx1+1,arg.size()-(has_idx2+2)));
+        } catch (std::invalid_argument &) {
+          type = UNKNOWN;
+        }
+      }
+    } else name = arg.substr(2);
+  } else name = arg;
+}
+
+/* ---------------------------------------------------------------------- */
+
+char *ArgInfo::copy_name()
+{
+  char *dest = new char[name.size()+1];
+  strcpy(dest,name.c_str());
+  return dest;
+}
+

src/arg_info.h

@@ -0,0 +1,71 @@
+/* -*- c++ -*- ----------------------------------------------------------
+   LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
+   http://lammps.sandia.gov, Sandia National Laboratories
+   Steve Plimpton, sjplimp@sandia.gov
+
+   Copyright (2003) Sandia Corporation.  Under the terms of Contract
+   DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
+   certain rights in this software.  This software is distributed under
+   the GNU General Public License.
+
+   See the README file in the top-level LAMMPS directory.
+------------------------------------------------------------------------- */
+
+#ifndef LMP_ARG_INFO_H
+#define LMP_ARG_INFO_H
+
+/*! \file arg_info.h */
+
+#include <string>
+
+namespace LAMMPS_NS {
+  class ArgInfo {
+  public:
+    enum {
+      ERROR          =-2,
+      UNKNOWN        =-1,
+      NONE           = 0,
+      X              = 1<<0,
+      V              = 1<<1,
+      F              = 1<<2,
+      COMPUTE        = 1<<3,
+      FIX            = 1<<4,
+      VARIABLE       = 1<<5,
+      KEYWORD        = 1<<6,
+      TYPE           = 1<<7,
+      MOLECULE       = 1<<8,
+      DNAME          = 1<<9,
+      INAME          = 1<<10,
+      DENSITY_NUMBER = 1<<11,
+      DENSITY_MASS   = 1<<12,
+      MASS           = 1<<13,
+      TEMPERATURE    = 1<<14,
+      BIN1D          = 1<<15,
+      BIN2D          = 1<<16,
+      BIN3D          = 1<<17,
+      BINSPHERE      = 1<<18,
+      BINCYLINDER    = 1<<19
+    };
+
+    ArgInfo(const std::string &arg, int allowed=COMPUTE|FIX|VARIABLE);
+    virtual ~ArgInfo() {}
+
+  public:
+    int  get_type() const { return type; }
+    int  get_dim()  const { return dim; }
+    int  get_index1() const { return index1; }
+    int  get_index2() const { return index2; }
+    const char *get_name() const { return name.c_str(); }
+    char *copy_name();
+
+  private:
+    std::string name;
+    int type, dim, index1, index2;
+
+    // disabled standard methods
+    ArgInfo() {}
+    ArgInfo(const ArgInfo &) {}
+    void operator=(const ArgInfo &) {}
+  };
+}
+#endif