git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@10150 f3b2605a-c512-4ea7-a41b-209d697bcdaa

src/MANYBODY/pair_adp.cpp

@@ -545,7 +545,7 @@ void PairADP::read_file(char *filename)
   char line[MAXLINE];
 
   if (me == 0) {
-    fp = fopen(filename,"r");
+    fp = open_potential(filename);
     if (fp == NULL) {
       char str[128];
       sprintf(str,"Cannot open ADP potential file %s",filename);

src/MANYBODY/pair_airebo.cpp

@@ -3333,7 +3333,7 @@ void PairAIREBO::read_file(char *filename)
   // read file on proc 0
 
   if (me == 0) {
-    FILE *fp = fopen(filename,"r");
+    FILE *fp = open_potential(filename);
     if (fp == NULL) {
       char str[128];
       sprintf(str,"Cannot open AIREBO potential file %s",filename);

src/MANYBODY/pair_bop.cpp

@@ -8210,7 +8210,7 @@ void PairBOP::read_file(char *filename)
   rcore=0.1;
 
   if (me == 0) {
-    FILE *fp = fopen(filename,"r");
+    FILE *fp = open_potential(filename);
     if (fp == NULL) {
       char str[128];
       sprintf(str,"Cannot open BOP potential file %s",filename);
@@ -8270,7 +8270,7 @@ void PairBOP::read_file(char *filename)
   if (me == 0) {
     words = new char*[bop_types];
     for(i=0;i<bop_types;i++) words[i]=NULL;
-    FILE *fp = fopen(filename,"r");
+    FILE *fp = open_potential(filename);
     if (fp == NULL) {
       char str[128];
       sprintf(str,"Cannot open BOP potential file %s",filename);
@@ -8434,7 +8434,7 @@ void PairBOP::read_table(char *filename)
   MPI_Comm_rank(world,&me);
 
   if (me == 0) {
-    FILE *fp = fopen(filename,"r");
+    FILE *fp = open_potential(filename);
     if (fp == NULL) {
       char str[128];
       sprintf(str,"Cannot open BOP potential file %s",filename);
@@ -8483,7 +8483,7 @@ void PairBOP::read_table(char *filename)
   allocate();
 
   if (me == 0) {
-    FILE *fp = fopen(filename,"r");
+    FILE *fp = open_potential(filename);
     if (fp == NULL) {
       char str[128];
       sprintf(str,"Cannot open BOP potential file %s",filename);

src/MANYBODY/pair_comb.cpp

@@ -572,7 +572,7 @@ void PairComb::read_file(char *file)
 
   FILE *fp;
   if (comm->me == 0) {
-    fp = fopen(file,"r");
+    fp = open_potential(file);
     if (fp == NULL) {
       char str[128];
       sprintf(str,"Cannot open COMB potential file %s",file);

src/MANYBODY/pair_eam.cpp

@@ -439,7 +439,7 @@ void PairEAM::read_file(char *filename)
   char line[MAXLINE];
 
   if (me == 0) {
-    fptr = fopen(filename,"r");
+    fptr = open_potential(filename);
     if (fptr == NULL) {
       char str[128];
       sprintf(str,"Cannot open EAM potential file %s",filename);

src/MANYBODY/pair_eam_alloy.cpp

@@ -122,7 +122,7 @@ void PairEAMAlloy::read_file(char *filename)
   char line[MAXLINE];
 
   if (me == 0) {
-    fptr = fopen(filename,"r");
+    fptr = open_potential(filename);
     if (fptr == NULL) {
       char str[128];
       sprintf(str,"Cannot open EAM potential file %s",filename);

src/MANYBODY/pair_eam_fs.cpp

@@ -122,7 +122,7 @@ void PairEAMFS::read_file(char *filename)
   char line[MAXLINE];
 
   if (me == 0) {
-    fptr = fopen(filename,"r");
+    fptr = open_potential(filename);
     if (fptr == NULL) {
       char str[128];
       sprintf(str,"Cannot open EAM potential file %s",filename);

src/MANYBODY/pair_eim.cpp

@@ -457,7 +457,7 @@ void PairEIM::read_file(char *filename)
   FILE *fptr;
 
   if (me == 0) {
-    fptr = fopen(filename,"r");
+    fptr = open_potential(filename);
     if (fptr == NULL) {
       char str[128];
       sprintf(str,"Cannot open EIM potential file %s",filename);

src/MANYBODY/pair_lcbop.cpp

@@ -984,7 +984,7 @@ void PairLCBOP::read_file(char *filename)
   // read file on proc 0
 
   if (me == 0) {
-    FILE *fp = fopen(filename,"r");
+    FILE *fp = open_potential(filename);
     if (fp == NULL) {
       char str[128];
       sprintf(str,"Cannot open LCBOP potential file %s",filename);

src/MANYBODY/pair_sw.cpp

@@ -336,7 +336,7 @@ void PairSW::read_file(char *file)
 
   FILE *fp;
   if (comm->me == 0) {
-    fp = fopen(file,"r");
+    fp = open_potential(file);
     if (fp == NULL) {
       char str[128];
       sprintf(str,"Cannot open Stillinger-Weber potential file %s",file);

src/MANYBODY/pair_tersoff.cpp

@@ -376,7 +376,7 @@ void PairTersoff::read_file(char *file)
 
   FILE *fp;
   if (comm->me == 0) {
-    fp = fopen(file,"r");
+    fp = open_potential(file);
     if (fp == NULL) {
       char str[128];
       sprintf(str,"Cannot open Tersoff potential file %s",file);

src/MANYBODY/pair_tersoff_zbl.cpp

@@ -74,7 +74,7 @@ void PairTersoffZBL::read_file(char *file)
 
   FILE *fp;
   if (comm->me == 0) {
-    fp = fopen(file,"r");
+    fp = open_potential(file);
     if (fp == NULL) {
       char str[128];
       sprintf(str,"Cannot open Tersoff potential file %s",file);

src/USER-MISC/pair_cdeam.cpp

@@ -461,7 +461,7 @@ void PairCDEAM::read_h_coeff(char *filename)
                 FILE *fp;
                 char line[MAXLINE];
                 char nextline[MAXLINE];
-                fp = fopen(filename,"r");
+                fp = open_potential(filename);
                 if (fp == NULL) {
                         char str[128];
                         sprintf(str,"Cannot open EAM potential file %s", filename);

src/USER-MISC/pair_edip.cpp

@@ -879,7 +879,7 @@ void PairEDIP::read_file(char *file)
 
   FILE *fp;
   if (comm->me == 0) {
-    fp = fopen(file,"r");
+    fp = open_potential(file);
     if (fp == NULL) {
       char str[128];
       sprintf(str,"Cannot open EDIP potential file %s",file);

src/USER-MISC/pair_meam_spline.cpp

@@ -434,7 +434,7 @@ void PairMEAMSpline::coeff(int narg, char **arg)
 void PairMEAMSpline::read_file(const char* filename)
 {
         if(comm->me == 0) {
-                FILE *fp = fopen(filename, "r");
+                FILE *fp = open_potential(filename);
                 if(fp == NULL) {
                         char str[1024];
                         sprintf(str,"Cannot open spline MEAM potential file %s", filename);

src/USER-MISC/pair_meam_sw_spline.cpp

@@ -463,7 +463,7 @@ void PairMEAMSWSpline::coeff(int narg, char **arg)
 void PairMEAMSWSpline::read_file(const char* filename)
 {
         if(comm->me == 0) {
-                FILE *fp = fopen(filename, "r");
+                FILE *fp = open_potential(filename);
                 if(fp == NULL) {
                         char str[1024];
                         sprintf(str,"Cannot open spline MEAM potential file %s", filename);

src/USER-MISC/pair_tersoff_table.cpp

@@ -857,7 +857,7 @@ void PairTersoffTable::read_file(char *file)
 
   FILE *fp;
   if (comm->me == 0) {
-    fp = fopen(file,"r");
+    fp = open_potential(file);
     if (fp == NULL) {
       char str[128];
       sprintf(str,"Cannot open Tersoff potential file %s",file);

src/USER-OMP/pair_eam_alloy_omp.cpp

@@ -121,7 +121,7 @@ void PairEAMAlloyOMP::read_file(char *filename)
   char line[MAXLINE];
 
   if (me == 0) {
-    fptr = fopen(filename,"r");
+    fptr = open_potential(filename);
     if (fptr == NULL) {
       char str[128];
       sprintf(str,"Cannot open EAM potential file %s",filename);

src/USER-OMP/pair_eam_fs_omp.cpp

@@ -121,7 +121,7 @@ void PairEAMFSOMP::read_file(char *filename)
   char line[MAXLINE];
 
   if (me == 0) {
-    fptr = fopen(filename,"r");
+    fptr = open_potential(filename);
     if (fptr == NULL) {
       char str[128];
       sprintf(str,"Cannot open EAM potential file %s",filename);

src/USER-OMP/pair_tersoff_zbl_omp.cpp

@@ -94,7 +94,7 @@ void PairTersoffZBLOMP::read_file(char *file)
 
   FILE *fp;
   if (comm->me == 0) {
-    fp = fopen(file,"r");
+    fp = open_potential(file);
     if (fp == NULL) {
       char str[128];
       sprintf(str,"Cannot open Tersoff potential file %s",file);

src/pair.cpp

@@ -16,6 +16,7 @@
 ------------------------------------------------------------------------- */
 
 #include "mpi.h"
+#include "ctype.h"
 #include "float.h"
 #include "limits.h"
 #include "math.h"
@@ -1613,6 +1614,71 @@ void Pair::init_bitmap(double inner, double outer, int ntablebits,
   masklo = rsq_lookup.i & ~(nmask);
 }
 
+/* ----------------------------------------------------------------------
+   open a potential file as specified
+   failing that, search in dir specified by env variable LAMMPS_POTENTIALS
+------------------------------------------------------------------------- */
+  
+FILE *Pair::open_potential(const char *name)
+{
+  FILE *fp;
+
+  // attempt to open file directly
+  // if successful, return ptr
+
+  fp = fopen(name,"r");
+  if (fp) return fp;
+
+  // try the environment variable directory
+
+  const char *path = getenv("LAMMPS_POTENTIALS");
+  if (path == NULL) return NULL;
+
+  const char *pot = potname(name);
+  size_t len1 = strlen(path);
+  size_t len2 = strlen(pot);
+
+  char *newpath = new char[len1+len2];
+  strcpy(newpath,path);
+#if defined(_WIN32)
+  newpath[len1] = '\\';
+  newpath[len1+1] = 0;
+#else
+  newpath[len1] = '/';
+  newpath[len1+1] = 0;
+#endif
+  strcat(newpath,pot);
+  
+  fp = fopen(newpath,"r");
+  delete[] newpath;
+  return fp;
+}
+
+/* ----------------------------------------------------------------------
+   strip off leading part of path, return just the filename
+------------------------------------------------------------------------- */
+
+const char *Pair::potname(const char *path)
+{
+  const char *pot;
+
+#if defined(_WIN32)
+  // skip over the disk drive part of windows pathnames
+  if (isalpha(path[0]) && path[1] == ':') 
+    path += 2;
+#endif
+
+  for (pot = path; *path != '\0'; ++path) {
+#if defined(_WIN32)
+    if ((*path == '\\') || (*path == '/')) pot = path + 1;
+#else
+    if (*path == '/') pot = path + 1;
+#endif
+  }
+
+  return pot;
+}
+
 /* ---------------------------------------------------------------------- */
 
 double Pair::memory_usage()
@@ -1621,3 +1687,68 @@ double Pair::memory_usage()
   bytes += comm->nthreads*maxvatom*6 * sizeof(double);
   return bytes;
 }
+
+/* ---------------------------------------------------------------------- */
+
+// helper function to strip off leading part of the path
+#include <ctype.h>
+
+static const char *potname(const char *path)
+{
+  const char *pot;
+
+#if defined(_WIN32)
+  /* Skip over the disk drive part in windows pathnames */
+  if (isalpha(path[0]) && path[1] == ':') 
+    path += 2;
+#endif
+
+  for (pot = path; *path != NULL; ++path) {
+#if defined(_WIN32)
+    if ((*path == '\\') || (*path == '/'))
+      pot = path + 1;
+#else
+    if (*path == '/')
+      pot = path + 1;
+#endif
+  }
+
+  return pot;
+}
+  
+/* this subroutine will try to fopen(3) a potential file in the provided
+   path, but failing that, it will search in a directory pointed to by
+   the environment variable LAMMPS_POTENTIALS */
+
+FILE *LAMMPS_NS::open_potential(const char *name)
+{
+  FILE *fp;
+
+  // try to open file directly and return pointer, if successful.
+  fp = fopen(name,"r");
+  if (fp) return fp;
+
+  // direct open failed, now try the directory from the environment.
+  const char *path = getenv("LAMMPS_POTENTIALS");
+  if (path == NULL) return NULL;
+
+  const char *pot = potname(name);
+  size_t len1 = strlen(path);
+  size_t len2 = strlen(pot);
+
+  char *newpath = new char[len1+len2];
+  strcpy(newpath,path);
+#if defined(_WIN32)
+  newpath[len1] = '\\';
+  newpath[len1+1] = 0;
+#else
+  newpath[len1] = '/';
+  newpath[len1+1] = 0;
+#endif
+  strcat(newpath,pot);
+  
+  // now try new path.
+  fp = fopen(newpath,"r");
+  delete[] newpath;
+  return fp;
+}

src/pair.h

@@ -208,11 +208,16 @@ class Pair : protected Pointers {
                       double, double, double, double, double, double);
   void virial_fdotr_compute();
 
+  FILE *open_potential(const char *);
+  const char *potname(const char *);
+
   inline int sbmask(int j) {
     return j >> SBBITS & 3;
   }
 };
 
+// fopen wrapper that also looks in $LAMMPS_POTENTIALS for potential files
+FILE *open_potential(const char *);
 }
 
 #endif