Fix memory dup free issue

CHANGELOG.md

@@ -1,9 +1,10 @@
 # CHANGELOG
 
-## 3.13.12 - <not released>
+## 3.13.12 - 2022-05-20
 
 - Fixed crash on no arguments to pretty_generate. Now raises an exception.
 - Register all classes and globals.
+- Fixed memory issue with dumping.
 
 ## 3.13.11 - 2022-01-05
 

ext/oj/dump.c

@@ -562,7 +562,6 @@ void oj_dump_obj_to_json_using_params(VALUE obj, Options copts, Out out, int arg
     if (0 == out->buf) {
         oj_out_init(out);
     }
-    out->cur      = out->buf;
     out->circ_cnt = 0;
     out->opts     = copts;
     out->hash_cnt = 0;
@@ -685,7 +684,6 @@ void oj_write_obj_to_stream(VALUE obj, VALUE stream, Options copts) {
         oj_out_free(&out);
         rb_raise(rb_eArgError, "to_stream() expected an IO Object.");
     }
-
     oj_out_free(&out);
 }
 
@@ -936,14 +934,15 @@ void oj_dump_raw(const char *str, size_t cnt, Out out) {
 }
 
 void oj_out_init(Out out) {
-  out->buf = out->stack_buffer;
-  out->end = out->buf + sizeof(out->stack_buffer) - BUFFER_EXTRA;
-  out->allocated = false;
+    out->buf = out->stack_buffer;
+    out->cur = out->buf;
+    out->end = out->buf + sizeof(out->stack_buffer) - BUFFER_EXTRA;
+    out->allocated = false;
 }
 
 void oj_out_free(Out out) {
     if (out->allocated) {
-        xfree(out->buf);
+        xfree(out->buf); // TBD
     }
 }
 
@@ -952,6 +951,7 @@ void oj_grow_out(Out out, size_t len) {
     long   pos  = out->cur - out->buf;
     char  *buf  = out->buf;
 
+    printf("*** grow %ld\n", len);
     size *= 2;
     if (size <= len * 2 + pos) {
         size += len;

ext/oj/string_writer.c

@@ -48,10 +48,18 @@ void oj_str_writer_init(StrWriter sw, int buf_size) {
     *sw->types     = '\0';
     sw->keyWritten = 0;
 
-    oj_out_init(&sw->out);
-    assure_size(&sw->out, buf_size);
-
+    if (0 == buf_size) {
+        buf_size = 4096;
+    } else if (buf_size < 1024) {
+        buf_size = 1024;
+    }
+    // Must be allocated. Using the out.stack_buffer results in double frees
+    // and I haven't figured out why yet.
+    sw->out.buf        = ALLOC_N(char, buf_size);
     sw->out.cur        = sw->out.buf;
+    sw->out.end        = sw->out.buf + buf_size - BUFFER_EXTRA;
+    sw->out.allocated  = true;
+
     *sw->out.cur       = '\0';
     sw->out.circ_cache = NULL;
     sw->out.circ_cnt   = 0;