X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=command.c;h=9cf1967faa4bdb4a3f12d313e2a322881f787d1f;hp=cdc42fa1a220662ac7413b52fc40aba0f56e14d8;hb=2830b9f8;hpb=e151dbb79eac16326585ec0a33cf48029f5f22f4

diff --git a/command.c b/command.c
index cdc42fa1..9cf1967f 100644
--- a/command.c
+++ b/command.c
@@ -15,6 +15,7 @@
 #include "para.h"
 #include "error.h"
 #include "crypt.h"
+#include "sideband.h"
 #include "command.h"
 #include "server.cmdline.h"
 #include "string.h"
@@ -191,6 +192,118 @@ static int check_sender_args(int argc, char * const * argv, struct sender_comman
 	return 1;
 }
 
+/**
+ * Send a sideband packet through a blocking file descriptor.
+ *
+ * \param scc fd and crypto keys.
+ * \param buf The buffer to send.
+ * \param numbytes The size of \a buf.
+ * \param band The sideband designator of this packet.
+ * \param dont_free If true, never deallocate \a buf.
+ *
+ * The nonblock flag must be disabled for the file descriptor given by \a scc.
+ *
+ * Stream cipher encryption is automatically activated if neccessary via the
+ * sideband transformation, depending on the value of \a band.
+ *
+ * \return Standard.
+ *
+ * \sa \ref send_sb_va().
+ */
+int send_sb(struct stream_cipher_context *scc, void *buf, size_t numbytes,
+		int band, bool dont_free)
+{
+	int ret;
+	struct sb_context *sbc;
+	struct iovec iov[2];
+	struct sb_buffer sbb = SBB_INIT(band, buf, numbytes);
+	sb_transformation trafo = band < SBD_PROCEED? NULL : sc_trafo;
+
+	sbc = sb_new_send(&sbb, dont_free, trafo, scc->send);
+	do {
+		ret = sb_get_send_buffers(sbc, iov);
+		ret = xwritev(scc->fd, iov, ret);
+		if (ret < 0)
+			goto fail;
+	} while (sb_sent(sbc, ret) == false);
+	return 1;
+fail:
+	sb_free(sbc);
+	return ret;
+}
+
+/**
+ * Create a variable sized buffer and send it as a sideband packet.
+ *
+ * \param scc Passed to \ref send_sb.
+ * \param band See \ref send_sb.
+ * \param fmt The format string.
+ *
+ * \return The return value of the underlying call to \ref send_sb.
+ */
+__printf_3_4 int send_sb_va(struct stream_cipher_context *scc, int band,
+		const char *fmt, ...)
+{
+	va_list ap;
+	char *msg;
+	int ret;
+
+	va_start(ap, fmt);
+	ret = xvasprintf(&msg, fmt, ap);
+	va_end(ap);
+	return send_sb(scc, msg, ret, band, false);
+}
+
+/**
+ * Send a sideband packet through a blocking file descriptor.
+ *
+ * \param scc fd and crypto keys.
+ * \param expected_band The expected band designator.
+ * \param max_size Passed to \ref sb_new_recv().
+ * \param result Body of the sideband packet is returned here.
+ *
+ * If \a expected_band is not \p SBD_ANY, the band designator of the received
+ * sideband packet is compared to \a expected_band and a mismatch is considered
+ * an error.
+ *
+ * \return Standard.
+ */
+int recv_sb(struct stream_cipher_context *scc,
+		enum sb_designator expected_band,
+		size_t max_size, struct iovec *result)
+{
+	int ret;
+	struct sb_context *sbc;
+	struct iovec iov;
+	struct sb_buffer sbb;
+	sb_transformation trafo;
+
+	trafo = expected_band != SBD_ANY && expected_band < SBD_PROCEED?
+		NULL : sc_trafo;
+	sbc = sb_new_recv(max_size, trafo, scc->recv);
+	for (;;) {
+		sb_get_recv_buffer(sbc, &iov);
+		ret = recv_bin_buffer(scc->fd, iov.iov_base, iov.iov_len);
+		if (ret == 0)
+			ret = -E_EOF;
+		if (ret < 0)
+			goto fail;
+		ret = sb_received(sbc, ret, &sbb);
+		if (ret < 0)
+			goto fail;
+		if (ret > 0)
+			break;
+	}
+	ret = -E_BAD_BAND;
+	if (expected_band != SBD_ANY && sbb.band != expected_band)
+		goto fail;
+	*result = sbb.iov;
+	return 1;
+fail:
+	sb_free(sbc);
+	return ret;
+}
+
 int com_sender(struct command_context *cc)
 {
 	int i, ret;