asprintf: new asprintf module.

[ccan] / ccan / asprintf / asprintf.h

diff --git a/ccan/asprintf/asprintf.h b/ccan/asprintf/asprintf.h
new file mode 100644 (file)
index 0000000..d006ea4
--- /dev/null
+++ b/ccan/asprintf/asprintf.h
@@ -0,0 +1,49 @@
+#ifndef CCAN_ASPRINTF_H
+#define CCAN_ASPRINTF_H
+#include "config.h"
+#include <ccan/compiler/compiler.h>
+
+/**
+ * afmt - allocate and populate a string with the given format.
+ * @fmt: printf-style format.
+ *
+ * This is a simplified asprintf interface.  Returns NULL on error.
+ */
+char *PRINTF_FMT(1, 2) afmt(const char *fmt, ...);
+
+#if HAVE_ASPRINTF
+#include <stdio.h>
+#else
+#include <stdarg.h>
+/**
+ * asprintf - printf to a dynamically-allocated string.
+ * @strp: pointer to the string to allocate.
+ * @fmt: printf-style format.
+ *
+ * Returns -1 (and leaves @strp undefined) on an error.  Otherwise returns
+ * number of bytes printed into @strp.
+ *
+ * Example:
+ *     static char *greeting(const char *name)
+ *     {
+ *             char *str;
+ *             int len = asprintf(&str, "Hello %s", name);
+ *             if (len < 0)
+ *                     return NULL;
+ *             return str;
+ *     }
+ */
+int PRINTF_FMT(2, 3) asprintf(char **strp, const char *fmt, ...);
+
+/**
+ * vasprintf - vprintf to a dynamically-allocated string.
+ * @strp: pointer to the string to allocate.
+ * @fmt: printf-style format.
+ *
+ * Returns -1 (and leaves @strp undefined) on an error.  Otherwise returns
+ * number of bytes printed into @strp.
+ */
+int vasprintf(char **strp, const char *fmt, va_list ap);
+#endif
+
+#endif /* CCAN_ASPRINTF_H */