add create_satisfying_shared_memories

i plan to use this for wasi-threads

CMakeLists.txt

@@ -213,6 +213,7 @@ list(APPEND lib_sources
 	"lib/waitlist.c")
 if(TOYWASM_ENABLE_WASI_THREADS)
 list(APPEND lib_sources
+	"lib/shared_memory.c"
 	"lib/wasi_threads.c")
 endif()
 endif()

lib/instance.c

@@ -240,7 +240,7 @@ memory_instance_free(struct meminst *mi)
 void
 memory_instance_destroy(struct meminst *mi)
 {
-	memory_instance_free(mi);
+        memory_instance_free(mi);
 }
 
 /* https://webassembly.github.io/spec/core/exec/modules.html#exec-instantiation

lib/instance.h

@@ -67,3 +67,6 @@ struct meminst;
 struct memtype;
 int memory_instance_create(struct meminst **mip, const struct memtype *mt);
 void memory_instance_destroy(struct meminst *mi);
+
+int create_satisfying_shared_memories(struct module *module,
+                                      struct import_object **imop);

lib/shared_memory.c

@@ -0,0 +1,80 @@
+#include <assert.h>
+
+#include "instance.h"
+#include "type.h"
+
+static void
+_dtor(struct import_object *imo)
+{
+        uint32_t i;
+        for (i = 0; i < imo->nentries; i++) {
+                struct import_object_entry *e = &imo->entries[i];
+                struct meminst *mi = e->u.mem;
+                if (mi != NULL) {
+                        memory_instance_destroy(mi);
+                }
+        }
+}
+
+int
+create_satisfying_shared_memories(struct module *m,
+                                  struct import_object **imop)
+{
+        struct import_object *imo = NULL;
+        uint32_t nsharedimports;
+        uint32_t i;
+        struct meminst *mi = NULL;
+        int ret;
+
+        nsharedimports = 0;
+        for (i = 0; i < m->nimports; i++) {
+                const struct import *im = &m->imports[i];
+                if (im->desc.type != IMPORT_MEMORY) {
+                        continue;
+                }
+                const struct memtype *mt = &im->desc.u.memtype;
+                if ((mt->flags & MEMTYPE_FLAG_SHARED) == 0) {
+                        continue;
+                }
+                nsharedimports++;
+        }
+
+        ret = import_object_alloc(nsharedimports, &imo);
+        if (ret != 0) {
+                goto fail;
+        }
+        imo->dtor = _dtor;
+
+        uint32_t idx = 0;
+        for (i = 0; i < m->nimports; i++) {
+                const struct import *im = &m->imports[i];
+                if (im->desc.type != IMPORT_MEMORY) {
+                        continue;
+                }
+                const struct memtype *mt = &im->desc.u.memtype;
+                if ((mt->flags & MEMTYPE_FLAG_SHARED) == 0) {
+                        continue;
+                }
+                ret = memory_instance_create(&mi, mt);
+                if (ret != 0) {
+                        goto fail;
+                }
+                assert(idx < imo->nentries);
+                struct import_object_entry *e = &imo->entries[idx++];
+                e->module_name = &im->module_name;
+                e->name = &im->name;
+                e->type = IMPORT_MEMORY;
+                e->u.mem = mi;
+        }
+
+        *imop = imo;
+        return 0;
+fail:
+        if (imo != NULL) {
+                import_object_destroy(imo);
+        }
+        if (mi != NULL) {
+                memory_instance_destroy(mi);
+        }
+        return ret;
+}