xstring: add a wrapper around open_memstream

diff --git a/include/xstring.h b/include/xstring.h
new file mode 100644 (file)
index 0000000..24738a6
--- /dev/null
+++ b/include/xstring.h
@@ -0,0 +1,68 @@
+#ifndef __XSTRING_H_
+#define __XSTRING_H_
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct xstring {
+       char* buf;
+       size_t size;
+       FILE* fp;
+};
+
+typedef struct xstring xstring;
+
+static inline xstring *
+xstring_new(void)
+{
+       xstring *str;
+
+       str = calloc(1, sizeof(*str));
+       if (str == NULL)
+               abort();
+       str->fp = open_memstream(&str->buf, &str->size);
+       if (str->fp == NULL)
+               abort();
+
+       return (str);
+}
+
+static inline void
+xstring_reset(xstring *str)
+{
+       if (str->buf)
+               memset(str->buf, 0, str->size);
+       rewind(str->fp);
+
+}
+
+static inline void
+xstring_free(xstring *str)
+{
+       if (str == NULL)
+               return;
+       fclose(str->fp);
+       free(str->buf);
+       free(str);
+}
+
+#define xstring_renew(s)      \
+do {                          \
+   if (s) {                   \
+     xstring_reset(s);        \
+   } else {                   \
+     s = xstring_new();       \
+   }                          \
+} while(0)
+
+static inline char *
+xstring_get(xstring *str)
+{
+       fclose(str->fp);
+       char *ret = str->buf;
+       free(str);
+       return (ret);
+}
+
+#endif