Add stream printing context.

This is some infrastructure which will support *print-circle*.

* lib.h (struct strm_ctx): Forward declared.
(struct cobj_ops): Add context parameter to print function
pointer.
(cobj_print_op, obj_print_impl): Add context parameter to
declarations.

* hash.c (hash_print_op): Take context argument and
pass it down in obj_print_impl calls.

* lib.c (cobj_print_op, out_quasi_str): Likewise
(obj_print_impl): Likewise, and also pass to
COBJ print method.
(obj_print, obj_pprint): Pass null pointer
as context argument to obj_print_impl.

* regex.c (regex_print): Take context parameter and ignore it.

* socket.c (dgram_print): Likewise.

* stream.h (struct strm_ctx): New struct type.
(struct strm_base): New ctx member, pointer to struct
strm_ctx.
(stream_print_op): Add context parameter to declaration.
(get_set_ctx, get_ctx): Declared.

* stream.c (strm_base_init): Add null pointer to initializer.
(strm_base_cleanup): Add assertion against context pointer
being non-null: that indicates that some stream operation
installed a context pointer and neglected to restore it to
null before returning, which is bad because context will be
stack allocated.
(stream_print_op, stdio_stream_print, cat_stream_print): Take
context parameter and ignore it.
(get_set_ctx, get_ctx): New functions.

* struct.c (struct_type_print): Take context parameter and
ignore it.
(struct_inst_print): Take context parameter and pass
down to obj_print_impl.

1 files changed, 9 insertions, 1 deletions

diff --git a/stream.h b/stream.h
index 14ef8e4f..818ad9cd 100644
--- a/stream.h
+++ b/stream.h
@@ -37,12 +37,18 @@ enum indent_mode {
   indent_code
 };
 
+struct strm_ctx {
+  val obj_hash;
+  val counter;
+};
+
 struct strm_base {
   enum indent_mode indent_mode;
   cnum data_width;
   cnum code_width;
   cnum indent_chars;
   cnum column;
+  struct strm_ctx *ctx;
 };
 
 struct strm_ops {
@@ -126,7 +132,7 @@ void strm_base_init(struct strm_base *s);
 void strm_base_cleanup(struct strm_base *s);
 void strm_base_mark(struct strm_base *s);
 void fill_stream_ops(struct strm_ops *ops);
-void stream_print_op(val stream, val out, val pretty);
+void stream_print_op(val stream, val out, val pretty, struct strm_ctx *);
 void stream_mark_op(val stream);
 void stream_destroy_op(val stream);
 struct stdio_mode parse_mode(val mode_str, struct stdio_mode m_dfl);
@@ -189,6 +195,8 @@ val get_indent(val stream);
 val set_indent(val stream, val indent);
 val inc_indent(val stream, val delta);
 val width_check(val stream, val alt);
+struct strm_ctx *get_set_ctx(val stream, struct strm_ctx *);
+struct strm_ctx *get_ctx(val stream);
 val get_string(val stream, val nchars, val close_after_p);
 val open_directory(val path);
 val open_file(val path, val mode_str);