add diskfree check to fix halt

doc/src/fix_halt.rst

@@ -14,23 +14,25 @@ Syntax
 * ID, group-ID are documented in :doc:`fix <fix>` command
 * halt = style name of this fix command
 * N = check halt condition every N steps
-* attribute = *bondmax* or *tlimit* or v\_name
+* attribute = *bondmax* or *tlimit* or *diskfree* or *v\_name*
   
   .. parsed-literal::
   
-       bondmax = length of longest bond in the system
+       bondmax = length of longest bond in the system (in length units)
-       tlimit = elapsed CPU time
+       tlimit = elapsed CPU time (in seconds)
+       diskfree = free disk space (in megabytes)
        v_name = name of :doc:`equal-style variable <variable>`
 
 * operator = "<" or "<=" or ">" or ">=" or "==" or "!=" or "\|\^"
 * avalue = numeric value to compare attribute to
 * zero or more keyword/value pairs may be appended
-* keyword = *error* or *message*
+* keyword = *error* or *message* or *path*
   
   .. parsed-literal::
   
        *error* value = *hard* or *soft* or *continue*
        *message* value = *yes* or *no*
+       *path* value = path to check for free space (may be in quotes)
 
 
 
@@ -38,25 +40,26 @@ Examples
 """"""""
 
 
-.. parsed-literal::
+.. code-block:: LAMMPS
 
    fix 10 all halt 1 bondmax > 1.5
-   fix 10 all print 10 v_myCheck != 0 error soft
+   fix 10 all halt 10 v_myCheck != 0 error soft
+   fix 10 all halt 100 diskfree < 100000.0 path "dump storage/."
 
 Description
 """""""""""
 
-Check a condition every N steps during a simulation run.  N must be >=
+Check a condition every N steps during a simulation run.  N must be >=1.
-1.  If the condition is met, exit the run immediately.  In this
+If the condition is met, exit the run.  In this context a "run" can be
-context a "run" can be dynamics or minimization iterations, as
+dynamics or minimization iterations, as specified by the :doc:`run
-specified by the :doc:`run <run>` or :doc:`minimize <minimize>` command.
+<run>` or :doc:`minimize <minimize>` command.
 
 The specified group-ID is ignored by this fix.
 
-The specified *attribute* can be one of the options listed above,
+The specified *attribute* can be one of the options listed above, namely
-namely *bondmax* or *tlimit*\ , or an :doc:`equal-style variable <variable>` referenced as *v\_name*, where "name" is the
+*bondmax*, *tlimit*\ , *diskfree*\ , or an :doc:`equal-style variable
-name of a variable that has been defined previously in the input
+<variable>` referenced as *v\_name*, where "name" is the name of a
-script.
+variable that has been defined previously in the input script.
 
 The *bondmax* attribute will loop over all bonds in the system,
 compute their current lengths, and set *attribute* to the longest bond
@@ -80,6 +83,14 @@ a run is performing 1000s of timesteps/sec, the overhead for syncing
 the timer frequently across a large number of processors may be
 non-negligible.
 
+The *diskfree* attribute will check for available disk space (in
+megabytes) on supported operating systems. By default it will
+check the file system of the current working directory.  This
+can be changed with the optional *path* keyword, which will take
+the path to a file or folder on the file system to be checked
+as argument.  This path must be given with single or double quotes,
+if it contains blanks or other special characters (like \$).
+
 Equal-style variables evaluate to a numeric value.  See the
 :doc:`variable <variable>` command for a description.  They calculate
 formulas which can involve mathematical operations, atom properties,
@@ -91,7 +102,7 @@ following "bondmax" variable will calculate the same quantity as the
 hstyle = bondmax option.
 
 
-.. parsed-literal::
+.. code-block:: LAMMPS
 
    compute         bdist all bond/local dist
    compute         bmax all reduce max c_bdist
@@ -100,7 +111,7 @@ hstyle = bondmax option.
 Thus these two versions of a fix halt command will do the same thing:
 
 
-.. parsed-literal::
+.. code-block:: LAMMPS
 
    fix 10 all halt 1 bondmax > 1.5
    fix 10 all halt 1 v_bondmax > 1.5
@@ -156,7 +167,7 @@ the :doc:`run <run>` command.
 
 Restrictions
 """"""""""""
- none
+The *diskfree* attribute is currently only supported on Linux.
 
 Related commands
 """"""""""""""""
@@ -166,4 +177,4 @@ Related commands
 Default
 """""""
 
-The option defaults are error = hard and message = yes.
+The option defaults are error = hard, message = yes, and path = ".".

src/fix_halt.cpp

@@ -29,7 +29,7 @@
 using namespace LAMMPS_NS;
 using namespace FixConst;
 
-enum{BONDMAX,TLIMIT,VARIABLE};
+enum{BONDMAX,TLIMIT,DISKFREE,VARIABLE};
 enum{LT,LE,GT,GE,EQ,NEQ,XOR};
 enum{HARD,SOFT,CONTINUE};
 enum{NOMSG,YESMSG};
@@ -37,7 +37,7 @@ enum{NOMSG,YESMSG};
 /* ---------------------------------------------------------------------- */
 
 FixHalt::FixHalt(LAMMPS *lmp, int narg, char **arg) :
-  Fix(lmp, narg, arg), idvar(NULL)
+  Fix(lmp, narg, arg), idvar(NULL), dlimit_path(NULL)
 {
   if (narg < 7) error->all(FLERR,"Illegal fix halt command");
   nevery = force->inumeric(FLERR,arg[3]);
@@ -46,37 +46,45 @@ FixHalt::FixHalt(LAMMPS *lmp, int narg, char **arg) :
   // comparison args
 
   idvar = NULL;
+  int iarg = 4;
 
-  if (strcmp(arg[4],"tlimit") == 0) attribute = TLIMIT;
+  if (strcmp(arg[iarg],"tlimit") == 0) {
-  else if (strcmp(arg[4],"bondmax") == 0) attribute = BONDMAX;
+    attribute = TLIMIT;
-  else if (strncmp(arg[4],"v_",2) == 0) {
+  } else if (strcmp(arg[iarg],"diskfree") == 0) {
+    attribute = DISKFREE;
+    dlimit_path = new char[2];
+    strcpy(dlimit_path,".");
+  } else if (strcmp(arg[iarg],"bondmax") == 0) {
+    attribute = BONDMAX;
+  } else if (strncmp(arg[iarg],"v_",2) == 0) {
     attribute = VARIABLE;
-    int n = strlen(arg[4]);
+    int n = strlen(arg[iarg]);
     idvar = new char[n];
-    strcpy(idvar,&arg[4][2]);
+    strcpy(idvar,&arg[iarg][2]);
     ivar = input->variable->find(idvar);
     if (ivar < 0) error->all(FLERR,"Could not find fix halt variable name");
     if (input->variable->equalstyle(ivar) == 0)
       error->all(FLERR,"Fix halt variable is not equal-style variable");
   } else error->all(FLERR,"Invalid fix halt attribute");
 
-  if (strcmp(arg[5],"<") == 0) operation = LT;
+  ++iarg;
-  else if (strcmp(arg[5],"<=") == 0) operation = LE;
+  if (strcmp(arg[iarg],"<") == 0) operation = LT;
-  else if (strcmp(arg[5],">") == 0) operation = GT;
+  else if (strcmp(arg[iarg],"<=") == 0) operation = LE;
-  else if (strcmp(arg[5],">=") == 0) operation = GE;
+  else if (strcmp(arg[iarg],">") == 0) operation = GT;
-  else if (strcmp(arg[5],"==") == 0) operation = EQ;
+  else if (strcmp(arg[iarg],">=") == 0) operation = GE;
-  else if (strcmp(arg[5],"!=") == 0) operation = NEQ;
+  else if (strcmp(arg[iarg],"==") == 0) operation = EQ;
-  else if (strcmp(arg[5],"|^") == 0) operation = XOR;
+  else if (strcmp(arg[iarg],"!=") == 0) operation = NEQ;
+  else if (strcmp(arg[iarg],"|^") == 0) operation = XOR;
   else error->all(FLERR,"Invalid fix halt operator");
 
-  value = force->numeric(FLERR,arg[6]);
+  ++iarg;
+  value = force->numeric(FLERR,arg[iarg]);
 
   // parse optional args
 
   eflag = SOFT;
   msgflag = YESMSG;
-
+  ++iarg;
-  int iarg = 7;
   while (iarg < narg) {
     if (strcmp(arg[iarg],"error") == 0) {
       if (iarg+2 > narg) error->all(FLERR,"Illegal fix halt command");
@@ -91,6 +99,19 @@ FixHalt::FixHalt(LAMMPS *lmp, int narg, char **arg) :
       else if (strcmp(arg[iarg+1],"yes") == 0) msgflag = YESMSG;
       else error->all(FLERR,"Illegal fix halt command");
       iarg += 2;
+    } else if (strcmp(arg[iarg],"path") == 0) {
+      if (iarg+2 > narg) error->all(FLERR,"Illegal fix halt command");
+      ++iarg;
+      int len = strlen(arg[iarg])+1;
+      delete[] dlimit_path;
+      dlimit_path = new char[len];
+      // strip off quotes, if present
+      if ( ((arg[iarg][0] == '"') || (arg[iarg][0] == '\''))
+           && (arg[iarg][0] == arg[iarg][len-2]) ) {
+        strcpy(dlimit_path,&arg[iarg][1]);
+        dlimit_path[len-3] = '\0';
+      } else strcpy(dlimit_path,arg[iarg]);
+      ++iarg;
     } else error->all(FLERR,"Illegal fix halt command");
   }
 
@@ -109,6 +130,7 @@ FixHalt::FixHalt(LAMMPS *lmp, int narg, char **arg) :
 FixHalt::~FixHalt()
 {
   delete [] idvar;
+  delete [] dlimit_path;
 }
 
 /* ---------------------------------------------------------------------- */
@@ -140,6 +162,13 @@ void FixHalt::init()
   nextstep = (update->ntimestep/nevery)*nevery + nevery;
   thisstep = -1;
   tratio = 0.5;
+
+  // check if disk limit is supported
+
+  if (attribute == DISKFREE) {
+    if (diskfree() < 0.0)
+      error->all(FLERR,"Disk limit not supported by OS or illegal path");
+  }
 }
 
 /* ---------------------------------------------------------------------- */
@@ -162,6 +191,8 @@ void FixHalt::end_of_step()
   if (attribute == TLIMIT) {
     if (update->ntimestep != nextstep) return;
     attvalue = tlimit();
+  } else if (attribute == DISKFREE) {
+    attvalue = diskfree();
   } else if (attribute == BONDMAX) {
     attvalue = bondmax();
   } else {
@@ -194,7 +225,8 @@ void FixHalt::end_of_step()
   // print message with ID of fix halt in case multiple instances
 
   char str[128];
-  sprintf(str,"Fix halt %s condition met on step " BIGINT_FORMAT " with value %g",
+  sprintf(str,"Fix halt condition for fix-id %s met on step "
+          BIGINT_FORMAT " with value %g",
           id, update->ntimestep, attvalue);
 
   if (eflag == HARD) {
@@ -270,3 +302,31 @@ double FixHalt::tlimit()
 
   return cpu;
 }
+
+/* ----------------------------------------------------------------------
+   determine available disk space, if supported. Return -1 if not.
+------------------------------------------------------------------------- */
+#if defined(__linux)
+#include <sys/statvfs.h>
+#endif
+double FixHalt::diskfree()
+{
+#if defined(__linux)
+  struct statvfs fs;
+  double disk_free = -1.0;
+
+  if (dlimit_path) {
+    disk_free = 1.0e100;
+    int rv = statvfs(dlimit_path,&fs);
+    if (rv == 0)
+      disk_free = fs.f_bavail*fs.f_bsize/1048576.0;
+    else
+      disk_free = -1.0;
+    
+    MPI_Bcast(&disk_free,1,MPI_DOUBLE,0,world);
+  }
+  return disk_free;
+#else
+  return -1.0;
+#endif
+}

src/fix_halt.h

@@ -39,9 +39,11 @@ class FixHalt : public Fix {
   bigint nextstep,thisstep;
   double value,tratio;
   char *idvar;
+  char *dlimit_path;
 
   double bondmax();
   double tlimit();
+  double diskfree();
 };
 
 }
@@ -59,26 +61,26 @@ command-line option when running LAMMPS to see the offending line.
 
 E: Could not find fix halt variable name
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Fix halt variable is not equal-style variable
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Invalid fix halt attribute
 
-UNDOCUMENTED
+Self-explanatory.
 
 E: Invalid fix halt operator
 
-UNDOCUMENTED
+Self-explanatory.
 
-E: Fix halt %s condition met on step %ld with value %g
+E: Disk limit not supported by OS or illegal path
 
-UNDOCUMENTED
+Self-explanatory.
 
-U: Cannot open fix print file %s
+W: Fix halt condition for fix-id %s met on step %ld with value %g
 
-The output file generated by the fix print command cannot be opened
+Self explanatory.
 
 */