Add compression_level parameter to dump cfg/gz

src/COMPRESS/dump_cfg_gz.cpp

@@ -18,6 +18,7 @@
 #include "update.h"
 
 #include <cstring>
+#include <fmt/format.h>
 
 using namespace LAMMPS_NS;
 #define UNWRAPEXPAND 10.0
@@ -27,6 +28,8 @@ DumpCFGGZ::DumpCFGGZ(LAMMPS *lmp, int narg, char **arg) :
 {
   gzFp = NULL;
 
+  compression_level = Z_BEST_COMPRESSION;
+
   if (!compressed)
     error->all(FLERR,"Dump cfg/gz only writes compressed files");
 }
@@ -93,12 +96,15 @@ void DumpCFGGZ::openfile()
   // each proc with filewriter = 1 opens a file
 
   if (filewriter) {
+    std::string mode;
     if (append_flag) {
-      gzFp = gzopen(filecurrent,"ab9");
+      mode = fmt::format("ab{}", compression_level);
     } else {
-      gzFp = gzopen(filecurrent,"wb9");
+      mode = fmt::format("wb{}", compression_level);
     }
 
+    gzFp = gzopen(filecurrent, mode.c_str());
+
     if (gzFp == NULL) error->one(FLERR,"Cannot open dump file");
   } else gzFp = NULL;
 
@@ -164,3 +170,21 @@ void DumpCFGGZ::write()
   }
 }
 
+/* ---------------------------------------------------------------------- */
+
+int DumpCFGGZ::modify_param(int narg, char **arg)
+{
+  int consumed = DumpCFG::modify_param(narg, arg);
+  if(consumed == 0) {
+    if (strcmp(arg[0],"compression_level") == 0) {
+      if (narg < 2) error->all(FLERR,"Illegal dump_modify command");
+      int min_level = Z_DEFAULT_COMPRESSION;
+      int max_level = Z_BEST_COMPRESSION;
+      if (compression_level < 0 || compression_level > max_level)
+        error->all(FLERR, fmt::format("Illegal dump_modify command: compression level must in the range of [{}, {}]", min_level, max_level));
+      return 2;
+    }
+  }
+  return consumed;
+}
+

src/COMPRESS/dump_cfg_gz.h

@@ -31,12 +31,15 @@ class DumpCFGGZ : public DumpCFG {
   virtual ~DumpCFGGZ();
 
  protected:
+  int compression_level;
   gzFile gzFp;  // file pointer for the compressed output stream
 
   virtual void openfile();
   virtual void write_header(bigint);
   virtual void write_data(int, double *);
   virtual void write();
+
+  virtual int modify_param(int, char **);
 };
 
 }