1 files changed, 74 insertions, 0 deletions
diff --git a/lib9/vsmprint.c b/lib9/vsmprint.c
new file mode 100644
index 00000000..44789be5
--- /dev/null
+++ b/lib9/vsmprint.c
@@ -0,0 +1,74 @@
+/*
+ * The authors of this software are Rob Pike and Ken Thompson.
+ *              Copyright (c) 2002 by Lucent Technologies.
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose without fee is hereby granted, provided that this entire notice
+ * is included in all copies of any software which is or includes a copy
+ * or modification of this software and in all copies of the supporting
+ * documentation for such software.
+ * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
+ * WARRANTY.  IN PARTICULAR, NEITHER THE AUTHORS NOR LUCENT TECHNOLOGIES MAKE ANY
+ * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
+ * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
+ */
+#include "lib9.h"
+#include "fmtdef.h"
+
+static int
+fmtStrFlush(Fmt *f)
+{
+	char *s;
+	int n;
+
+	n = (int)f->farg;
+	n += 256;
+	f->farg = (void*)n;
+	s = f->start;
+	f->start = realloc(s, n);
+	if(f->start == nil){
+		free(s);
+		f->to = nil;
+		f->stop = nil;
+		return 0;
+	}
+	f->to = (char*)f->start + ((char*)f->to - s);
+	f->stop = (char*)f->start + n - 1;
+	return 1;
+}
+
+int
+fmtstrinit(Fmt *f)
+{
+	int n;
+
+	f->runes = 0;
+	n = 32;
+	f->start = malloc(n);
+	if(f->start == nil)
+		return -1;
+	f->to = f->start;
+	f->stop = (char*)f->start + n - 1;
+	f->flush = fmtStrFlush;
+	f->farg = (void*)n;
+	f->nfmt = 0;
+	return 0;
+}
+
+/*
+ * print into an allocated string buffer
+ */
+char*
+vsmprint(char *fmt, va_list args)
+{
+	Fmt f;
+	int n;
+
+	if(fmtstrinit(&f) < 0)
+		return nil;
+	f.args = args;
+	n = dofmt(&f, fmt);
+	if(n < 0)
+		return nil;
+	*(char*)f.to = '\0';
+	return f.start;
+}