From fce6f43f7af9500373605ac718d8765c7fa1c022 Mon Sep 17 00:00:00 2001
From: Justin Ethier <justin.ethier@gmail.com>
Date: Thu, 25 Aug 2016 23:38:09 -0400
Subject: [PATCH] Initial file

---
 mem-streams.c | 91 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 91 insertions(+)
 create mode 100644 mem-streams.c

diff --git a/mem-streams.c b/mem-streams.c
new file mode 100644
index 00000000..8bd339a9
--- /dev/null
+++ b/mem-streams.c
@@ -0,0 +1,91 @@
+/** 
+ * Cyclone Scheme
+ * https://github.com/justinethier/cyclone
+ *
+ * Copyright (c) 2014-2016, Justin Ethier
+ * All rights reserved.
+ *
+ * This file contains platform-specific code for memory streams.
+ */
+
+#include "cyclone/types.h"
+#include "cyclone/runtime.h"
+#include <errno.h>
+//#include <limits.h>
+//#include <ctype.h>
+
+/* These macros are hardcoded here to support functions in this module. */
+#define closcall1(td, clo, a1) \
+if (type_is_pair_prim(clo)) { \
+   Cyc_apply(td, 0, (closure)(a1), clo); \
+} else { \
+   ((clo)->fn)(td, 1, clo, a1);\
+}
+#define return_closcall1(td, clo, a1) { \
+ char top; \
+ if (stack_overflow(&top, (((gc_thread_data *)data)->stack_limit))) { \
+     object buf[1]; buf[0] = a1;\
+     GC(td, clo, buf, 1); \
+     return; \
+ } else {\
+     closcall1(td, (closure) (clo), a1); \
+     return;\
+ } \
+}
+
+port_type Cyc_io_open_output_string(void *data)
+{
+  make_port(p, NULL, 0);
+  errno = 0;
+  p.fp = open_memstream(&(p.mem_buf), &(p.mem_buf_len));
+  if (p.fp == NULL){
+    Cyc_rt_raise2(data, "Unable to open memory stream", obj_int2obj(errno));
+  }
+  return p;
+}
+
+void Cyc_io_get_output_string(void *data, object cont, object port)
+{
+  Cyc_check_port(data, port);
+  if (((port_type *)port)->mem_buf == NULL) {
+    Cyc_rt_raise2(data, "Not an in-memory port", port);
+  }
+  {
+    port_type *p = (port_type *)port;
+    make_string_with_len(s, p->mem_buf, p->mem_buf_len);
+    return_closcall1(data, cont, &s);
+  }
+}
+
+// TODO: when closing a memory port, need to free mem_buf if != NULL
+
+
+// Hacky approach to a minimal string buffer implementation. This may change in the future
+// For background see: http://stackoverflow.com/questions/539537/memory-buffer-as-file
+//port_type Cyc_io_open_output_string(void *data)
+//
+//// TODO: no, this is too hacky. fuck it, just use fmemopen or open_memstream
+//// for non-supported platforms we'll raise an error and not do anything
+//{
+//    FILE *f = fopen("/dev/null", "w");
+//    int i;
+//    int written = 0;
+//    char *buf = malloc(100000);
+//    make_port(p, NULL, 0); // TODO: probably wrong params, need to add buf to port obj and type
+//    //setbuffer(f, buf, 100000);
+//    if (0 != setvbuf (f, buf, _IOFBF, 100000)){
+//      // TODO: raise() instead?
+//      fprintf(stderr, "Unable to setvbuf!\n");
+//      exit(1);
+//    }
+//    for (i = 0; i < 1000; i++) {
+//        written += fprintf(f, "Number %d\n", i);
+//    }
+//    for (i = 0; i < written; i++) {
+//        printf("%c", buf[i]);
+//    }
+//    return p;
+//}
+//
+//// END string buffers
+