lib: add `%*pHX` + `%*pHS` hexdump in printfrr

(I'll get to `zlog_hexdump()` in a separate pass.)

Signed-off-by: David Lamparter <equinox@diac24.net>

1 files changed, 75 insertions, 0 deletions

diff --git a/lib/strformat.c b/lib/strformat.c
new file mode 100644
index 000000000..8e49a666f
--- /dev/null
+++ b/lib/strformat.c
@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2019  David Lamparter, for NetDEF, Inc.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <string.h>
+
+#include "printfrr.h"
+
+printfrr_ext_autoreg_p("HX", printfrr_hexdump)
+static ssize_t printfrr_hexdump(struct fbuf *buf, struct printfrr_eargs *ea,
+				const void *ptr)
+{
+	ssize_t ret = 0;
+	ssize_t input_len = printfrr_ext_len(ea);
+	char sep = ' ';
+	const uint8_t *pos, *end;
+
+	if (ea->fmt[0] == 'c') {
+		ea->fmt++;
+		sep = ':';
+	} else if (ea->fmt[0] == 'n') {
+		ea->fmt++;
+		sep = '\0';
+	}
+
+	if (input_len < 0)
+		return 0;
+
+	for (pos = ptr, end = pos + input_len; pos < end; pos++) {
+		if (sep && pos != ptr)
+			ret += bputch(buf, sep);
+		ret += bputhex(buf, *pos);
+	}
+
+	return ret;
+}
+
+/* string analog for hexdumps / the "this." in ("74 68 69 73 0a  |this.|") */
+
+printfrr_ext_autoreg_p("HS", printfrr_hexdstr)
+static ssize_t printfrr_hexdstr(struct fbuf *buf, struct printfrr_eargs *ea,
+				const void *ptr)
+{
+	ssize_t ret = 0;
+	ssize_t input_len = printfrr_ext_len(ea);
+	const uint8_t *pos, *end;
+
+	if (input_len < 0)
+		return 0;
+
+	for (pos = ptr, end = pos + input_len; pos < end; pos++) {
+		if (*pos >= 0x20 && *pos < 0x7f)
+			ret += bputch(buf, *pos);
+		else
+			ret += bputch(buf, '.');
+	}
+
+	return ret;
+}