Add missing stream_buffer.{h,c} files

tests/stream_buffer.c

@@ -0,0 +1,68 @@
+#include "stream_buffer.h"
+
+#include <string.h>
+
+static foug_bool_t foug_stream_buffer_at_end(void* cookie)
+{
+  const foug_buffer_t* buff = (const foug_buffer_t*)cookie;
+  return buff->pos >= buff->len;
+}
+
+static int foug_stream_buffer_error(void* cookie)
+{
+  const foug_buffer_t* buff = (const foug_buffer_t*)cookie;
+  return buff == NULL || buff->pos > buff->len;
+}
+
+static size_t foug_stream_buffer_read(void* cookie,
+                                      void* ptr,
+                                      size_t item_size,
+                                      size_t item_count)
+{
+  if (item_size > 0 && item_count > 0) {
+    foug_buffer_t* buff = (foug_buffer_t*)cookie;
+    const size_t buff_remaining_size = buff->len - buff->pos;
+    const size_t wanted_read_size = item_size * item_count;
+    const size_t next_read_size = wanted_read_size <= buff_remaining_size ? wanted_read_size :
+                                                                            buff_remaining_size;
+    const size_t next_read_item_count = next_read_size / item_size;
+
+    memcpy(ptr, (const char*)buff->ptr + buff->pos, next_read_item_count * item_size);
+    buff->pos += next_read_item_count * item_size;
+    return next_read_item_count;
+  }
+  else {
+    return 0;
+  }
+}
+
+static size_t foug_stream_buffer_write(void* cookie,
+                                       const void* ptr,
+                                       size_t item_size,
+                                       size_t item_count)
+{
+  if (item_size > 0 && item_count > 0) {
+    foug_buffer_t* buff = (foug_buffer_t*)cookie;
+    const size_t buff_remaining_size = buff->len - buff->pos;
+    const size_t wanted_write_size = item_size * item_count;
+    const size_t next_write_size = wanted_write_size <= buff_remaining_size ? wanted_write_size :
+                                                                              buff_remaining_size;
+    const size_t next_write_item_count = next_write_size / item_size;
+
+    memcpy((char*)buff->ptr + buff->pos, ptr, next_write_item_count * item_size);
+    buff->pos += next_write_item_count * item_size;
+    return next_write_item_count;
+  }
+  else {
+    return 0;
+  }
+}
+
+void foug_stream_set_buffer(foug_stream_t *stream, foug_buffer_t *buff)
+{
+  stream->cookie = buff;
+  stream->at_end_func = foug_stream_buffer_at_end;
+  stream->error_func = foug_stream_buffer_error;
+  stream->read_func = foug_stream_buffer_read;
+  stream->write_func = foug_stream_buffer_write;
+}

tests/stream_buffer.h

@@ -0,0 +1,15 @@
+#ifndef FOUG_STREAM_BUFFER_H
+#define FOUG_STREAM_BUFFER_H
+
+#include "../src/stream.h"
+
+typedef struct
+{
+  void*  ptr;
+  size_t len;
+  size_t pos;
+} foug_buffer_t;
+
+void foug_stream_set_buffer(foug_stream_t* stream, foug_buffer_t* buff);
+
+#endif /* FOUG_STREAM_BUFFER_H */