From f14ba70de62cbd47e074756b1f1aec1f3b77a02d Mon Sep 17 00:00:00 2001
From: Mattias Andrée <maandree@kth.se>
Date: Sun, 15 Sep 2024 00:47:51 +0200
Subject: Move man pages into man3/ and man7/
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Mattias Andrée <maandree@kth.se>
---
 man3/libkeccak_update.3 | 100 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 100 insertions(+)
 create mode 100644 man3/libkeccak_update.3

(limited to 'man3/libkeccak_update.3')

diff --git a/man3/libkeccak_update.3 b/man3/libkeccak_update.3
new file mode 100644
index 0000000..384e492
--- /dev/null
+++ b/man3/libkeccak_update.3
@@ -0,0 +1,100 @@
+.TH LIBKECCAK_UPDATE 3 LIBKECCAK
+.SH NAME
+libkeccak_update - Partially hash a message with erasure
+.SH SYNOPSIS
+.nf
+#include <libkeccak.h>
+
+int libkeccak_update(struct libkeccak_state *\fIstate\fP, const void *\fImsg\fP, size_t \fImsglen\fP);
+.fi
+.PP
+Link with
+.IR -lkeccak .
+.SH DESCRIPTION
+The
+.BR libkeccak_update ()
+function continues (or starts) hashing a message.
+The current state of the hashing is stored in
+.IR *state ,
+and will be updated. The message specified by the
+.I msg
+parameter with the byte-size specified by the
+.I msglen
+parameter, will be hashed.
+.PP
+The
+.BR libkeccak_update ()
+function may reallocate the state's message chunk buffer.
+When doing so, it attempts to do so as securely as possible,
+rather than as fast as possible.
+.SH RETURN VALUES
+The
+.BR libkeccak_update ()
+function returns 0 upon successful completion. On error,
+-1 is returned and
+.I errno
+is set to describe the error.
+.SH ERRORS
+The
+.BR libkeccak_update ()
+function may fail for any reason specified by the function
+.BR malloc (3).
+.SH NOTES
+Neither parameter by be
+.I NULL
+or 0.
+.SH EXAMPLE
+This example calculates the Keccak[b = 1024, c = 576, n = 256]
+hash of the input from stdin, and prints the hash, in hexadecimal
+form, to stdout.
+.PP
+.nf
+struct libkeccak_state state;
+struct libkeccak_spec spec;
+char binhash[256 / 8];
+char hexhash[256 / 8 * 2 + 1];
+char chunk[4 << 10];
+ssize_t len;
+
+spec.bitrate = 1024;
+spec.capacity = 576;
+spec.output = 256;
+if (libkeccak_state_initialise(&state, &spec) < 0)
+	goto fail;
+
+for (;;) {
+	len = read(STDIN_FILENO, chunk, sizeof(chunk));
+
+	if ((len < 0) && (errno == EINTR))
+		continue;
+	if (len < 0)
+		goto fail;
+	if (len == 0)
+		break;
+
+	if (libkeccak_update(&state, chunk, (size_t)len) < 0)
+		goto fail;
+}
+if (libkeccak_digest(&state, NULL, 0, 0, \(dq\(dq, binhash) < 0)
+	goto fail;
+
+libkeccak_behex_lower(hexhash, binhash, sizeof(binhash));
+printf(\(dq%s\en\(dq, hexhash);
+libkeccak_state_destroy(&state);
+.fi
+.SH NOTES
+For cSHAKE, the
+.BR libkeccak_cshake_initialise (3),
+must be called, once, immediately after
+state initialisation; before the first
+call to the
+.BR libkeccak_update ()
+function.
+.SH SEE ALSO
+.BR libkeccak_state_initialise (3),
+.BR libkeccak_cshake_initialise (3),
+.BR libkeccak_fast_update (3),
+.BR libkeccak_zerocopy_update (3),
+.BR libkeccak_fast_digest (3),
+.BR libkeccak_zerocopy_digest (3),
+.BR libkeccak_digest (3)
-- 
cgit v1.2.3-70-g09d2