1 files changed, 64 insertions, 0 deletions
diff --git a/misc/iobuf.c b/misc/iobuf.c
new file mode 100644
index 0000000..a7304c6
--- /dev/null
+++ b/misc/iobuf.c
@@ -0,0 +1,64 @@
+#include <errno.h>
+#include <inttypes.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "iobuf.h"
+
+#define GROWLEN (1 << 14)
+
+int
+buf_init(struct io_buffer *iob, size_t size)
+{
+    iob->buf_off = 0;
+    iob->buf_len = size;
+    iob->buf = malloc(size);
+    if (iob->buf == NULL)
+        return ENOMEM;
+    else
+        return 0;
+}
+
+int
+buf_grow(struct io_buffer *iob, size_t addlen)
+{
+    char *nbuf = realloc(iob->buf, iob->buf_len + addlen);
+    if (nbuf == NULL)
+        return ENOMEM;
+    else {
+        iob->buf = nbuf;
+        iob->buf_len += addlen;
+        return 0;
+    }
+}
+
+int
+buf_print(struct io_buffer *iob, const char *fmt, ...)
+{
+    int np;
+    va_list ap;
+    va_start(ap, fmt);
+    np = vsnprintf(NULL, 0, fmt, ap);
+    va_end(ap);
+    while (np + 1 > iob->buf_len - iob->buf_off)
+        if (buf_grow(iob, GROWLEN) != 0)
+            return ENOMEM;
+    va_start(ap, fmt);
+    vsnprintf(iob->buf + iob->buf_off, np + 1, fmt, ap);
+    va_end(ap);
+    iob->buf_off += np;
+    return 0;
+}
+
+int
+buf_write(struct io_buffer *iob, const void *buf, size_t len)
+{
+    while (iob->buf_len - iob->buf_off < len)
+        if (buf_grow(iob, GROWLEN) != 0)
+            return ENOMEM;
+    bcopy(buf, iob->buf + iob->buf_off, len);
+    iob->buf_off += len;
+    return 0;
+}