From b03e9609cefa2c3b8a6dd520250c26dfba3bc232 Mon Sep 17 00:00:00 2001
From: Axel Kohlmeyer <akohlmey@gmail.com>
Date: Fri, 13 Jan 2023 05:30:49 -0500
Subject: [PATCH] synchronize API with library.h, zero struct on allocation,
 determine exception support at runtime.

---
 examples/COUPLE/plugin/liblammpsplugin.c | 17 +++++++----------
 examples/COUPLE/plugin/liblammpsplugin.h | 21 +++++++++++----------
 examples/COUPLE/plugin/simple.c          |  6 ++++++
 3 files changed, 24 insertions(+), 20 deletions(-)

diff --git a/examples/COUPLE/plugin/liblammpsplugin.c b/examples/COUPLE/plugin/liblammpsplugin.c
index 0b7eda7537..759be31a81 100644
--- a/examples/COUPLE/plugin/liblammpsplugin.c
+++ b/examples/COUPLE/plugin/liblammpsplugin.c
@@ -56,7 +56,8 @@ liblammpsplugin_t *liblammpsplugin_load(const char *lib)
 #endif
   if (handle == NULL) return NULL;
 
-  lmp = (liblammpsplugin_t *) malloc(sizeof(liblammpsplugin_t));
+  lmp = (liblammpsplugin_t *) calloc(1, sizeof(liblammpsplugin_t));
+  lmp->abiversion = LAMMPSPLUGIN_ABI_VERSION;
   lmp->handle = handle;
 
 #ifdef _WIN32
@@ -179,15 +180,11 @@ liblammpsplugin_t *liblammpsplugin_load(const char *lib)
   ADDSYM(is_running);
   ADDSYM(force_timeout);
 
-#ifdef LAMMPS_EXCEPTIONS
-  lmp->has_exceptions = 1;
-  ADDSYM(has_error);
-  ADDSYM(get_last_error_message);
-#else
-  lmp->has_exceptions = 0;
-  lmp->has_error = NULL;
-  lmp->get_last_error_message = NULL;
-#endif
+  lmp->has_exceptions = lmp->config_has_exceptions();
+  if (lmp->has_exceptions) {
+    ADDSYM(has_error);
+    ADDSYM(get_last_error_message);
+  }
 
   ADDSYM(python_api_version);
   return lmp;
diff --git a/examples/COUPLE/plugin/liblammpsplugin.h b/examples/COUPLE/plugin/liblammpsplugin.h
index d31bdc4504..ee77fff31e 100644
--- a/examples/COUPLE/plugin/liblammpsplugin.h
+++ b/examples/COUPLE/plugin/liblammpsplugin.h
@@ -105,6 +105,7 @@ typedef void (*FixExternalFnPtr)(void *, int, int, int *, double **, double **);
 typedef void (*FixExternalFnPtr)(void *, int64_t, int, int *, double **, double **);
 #endif
 
+#define LAMMPSPLUGIN_ABI_VERSION 1
 struct _liblammpsplugin {
   int abiversion;
   int has_exceptions;
@@ -153,19 +154,19 @@ struct _liblammpsplugin {
   int (*extract_variable_datatype)(void *, const char *);
   int (*set_variable)(void *, char *, char *);
 
-  void (*gather_atoms)(void *, char *, int, int, void *);
-  void (*gather_atoms_concat)(void *, char *, int, int, void *);
-  void (*gather_atoms_subset)(void *, char *, int, int, int, int *, void *);
-  void (*scatter_atoms)(void *, char *, int, int, void *);
-  void (*scatter_atoms_subset)(void *, char *, int, int, int, int *, void *);
+  void (*gather_atoms)(void *, const char *, int, int, void *);
+  void (*gather_atoms_concat)(void *, const char *, int, int, void *);
+  void (*gather_atoms_subset)(void *, const char *, int, int, int, int *, void *);
+  void (*scatter_atoms)(void *, const char *, int, int, void *);
+  void (*scatter_atoms_subset)(void *, const char *, int, int, int, int *, void *);
 
   void (*gather_bonds)(void *, void *);
 
-  void (*gather)(void *, char *, int, int, void *);
-  void (*gather_concat)(void *, char *, int, int, void *);
-  void (*gather_subset)(void *, char *, int, int, int, int *,void *);
-  void (*scatter)(void *, char *, int, int, void *);
-  void (*scatter_subset)(void *, char *, int, int, int, int *, void *);
+  void (*gather)(void *, const char *, int, int, void *);
+  void (*gather_concat)(void *, const char *, int, int, void *);
+  void (*gather_subset)(void *, const char *, int, int, int, int *,void *);
+  void (*scatter)(void *, const char *, int, int, void *);
+  void (*scatter_subset)(void *, const char *, int, int, int, int *, void *);
 
 /* lammps_create_atoms() takes tagint and imageint as args
  * the ifdef insures they are compatible with rest of LAMMPS
diff --git a/examples/COUPLE/plugin/simple.c b/examples/COUPLE/plugin/simple.c
index 6cc453bd34..535086f7ad 100644
--- a/examples/COUPLE/plugin/simple.c
+++ b/examples/COUPLE/plugin/simple.c
@@ -92,6 +92,12 @@ int main(int narg, char **arg)
       if (me == 0) printf("ERROR: Could not load shared LAMMPS library\n");
       MPI_Abort(MPI_COMM_WORLD,1);
     }
+    /* must match the plugin ABI version */
+    if (plugin->abiversion != LAMMPSPLUGIN_ABI_VERSION) {
+      if (me == 0) printf("ERROR: Plugin abi version does not match: %d vs %d\n",
+                          plugin->abiversion, LAMMPSPLUGIN_ABI_VERSION);
+      MPI_Abort(MPI_COMM_WORLD,1);
+    }
   }
   if (lammps == 1) {
     if (plugin->open == NULL) {