use more const char pointers

src/atom.cpp

@@ -2508,7 +2508,7 @@ length of the data area, and a short description.
                  Typically the name of the pointer variable returned
  * \return       pointer to the requested data cast to ``void *`` or NULL */
 
-void *Atom::extract(char *name)
+void *Atom::extract(const char *name)
 {
   // --------------------------------------------------------------------
   // 4th customization section: customize by adding new variable name

src/atom.h

@@ -331,7 +331,7 @@ class Atom : protected Pointers {
 
   virtual void sync_modify(ExecutionSpace, unsigned int, unsigned int) {}
 
-  void *extract(char *);
+  void *extract(const char *);
 
   inline int* get_map_array() {return map_array;};
   inline int get_map_size() {return map_tag_max+1;};

src/library.cpp

@@ -807,7 +807,7 @@ recognized, the function returns -1.  Please also see :cpp:func:`lammps_extract_
  * \param  keyword  string with the name of the thermo keyword
  * \return          value of the queried setting or -1 if unknown */
 
-int lammps_extract_setting(void * handle, char *keyword)
+int lammps_extract_setting(void *handle, const char *keyword)
 {
   LAMMPS *lmp = (LAMMPS *) handle;
 
@@ -1073,7 +1073,7 @@ to be either an ``int`` or an ``int64_t``.  This is selected at
  * \return          pointer (cast to ``void *``) to the location of the
                     requested property. NULL if name is not known. */
 
-void *lammps_extract_global(void *handle, char *name)
+void *lammps_extract_global(void *handle, const char *name)
 {
   LAMMPS *lmp = (LAMMPS *) handle;
 
@@ -1165,7 +1165,7 @@ of the :cpp:func:`Atom::extract() <LAMMPS_NS::Atom::extract>` function.
  * \return         pointer (cast to ``void *``) to the location of the
  *                 requested data or ``NULL`` if not found. */
 
-void *lammps_extract_atom(void *handle, char *name)
+void *lammps_extract_atom(void *handle, const char *name)
 {
   LAMMPS *lmp = (LAMMPS *) handle;
   return lmp->atom->extract(name);
@@ -3792,7 +3792,7 @@ Valid categories are: *atom*\ , *integrate*\ , *minimize*\ ,
  * \param name     name of the style
  * \return 1 if included, 0 if not.
  */
-int lammps_has_style(void * handle, char * category, char * name) {
+int lammps_has_style(void *handle, const char *category, const char *name) {
   LAMMPS *lmp = (LAMMPS *) handle;
   Info info(lmp);
   return info.has_style(category, name) ? 0 : 1;
@@ -3813,7 +3813,7 @@ categories.
  * \param category category of styles
  * \return number of styles in category
  */
-int lammps_style_count(void * handle, char * category) {
+int lammps_style_count(void *handle, const char *category) {
   LAMMPS *lmp = (LAMMPS *) handle;
   Info info(lmp);
   return info.get_available_styles(category).size();
@@ -3839,7 +3839,8 @@ Please see :cpp:func:`lammps_has_style` for a list of valid categories.
  * \param buf_size size of the provided string buffer
  * \return 1 if successful, otherwise 0
  */
-int lammps_style_name(void* handle, char * category, int idx, char * buffer, int buf_size) {
+int lammps_style_name(void *handle, const char *category, int idx,
+                      const char *buffer, int buf_size) {
   LAMMPS *lmp = (LAMMPS *) handle;
   Info info(lmp);
   auto styles = info.get_available_styles(category);

src/library.h

@@ -108,9 +108,9 @@ void   lammps_extract_box(void *handle, double *boxlo, double *boxhi,
 void   lammps_reset_box(void *handle, double *boxlo, double *boxhi,
                         double xy, double yz, double xz);
 
-int    lammps_extract_setting(void *handle, char *keyword);
+int    lammps_extract_setting(void *handle, const char *keyword);
-void  *lammps_extract_global(void *handle, char *name);
+void  *lammps_extract_global(void *handle, const char *name);
-void  *lammps_extract_atom(void *handle, char *name);
+void  *lammps_extract_atom(void *handle, const char *name);
 
 #if !defined(LAMMPS_BIGBIG)
 int    lammps_create_atoms(void *handle, int n, int *id, int *type,
@@ -161,9 +161,9 @@ int lammps_config_has_jpeg_support();
 int lammps_config_has_ffmpeg_support();
 int lammps_config_has_exceptions();
 
-int lammps_has_style(void *, char *, char *);
+int lammps_has_style(void *, const char *, const char *);
-int lammps_style_count(void *, char *);
+int lammps_style_count(void *, const char *);
-int lammps_style_name(void *, char *, int, char *, int);
+int lammps_style_name(void *, const char *, int, const char *, int);
 
 /* ----------------------------------------------------------------------
  * Library functions for accessing neighbor lists