1 files changed, 40 insertions, 2 deletions

diff --git a/pkt-line.h b/pkt-line.h
index 5b28d43472..ad9a4a2cd7 100644
--- a/pkt-line.h
+++ b/pkt-line.h
@@ -3,6 +3,7 @@
 
 #include "git-compat-util.h"
 #include "strbuf.h"
+#include "sideband.h"
 
 /*
  * Write a packetized stream, where each line is preceded by
@@ -62,9 +63,13 @@ int write_packetized_from_buf(const char *src_in, size_t len, int fd_out);
  *
  * If options contains PACKET_READ_CHOMP_NEWLINE, a trailing newline (if
  * present) is removed from the buffer before returning.
+ *
+ * If options contains PACKET_READ_DIE_ON_ERR_PACKET, it dies when it sees an
+ * ERR packet.
  */
-#define PACKET_READ_GENTLE_ON_EOF (1u<<0)
-#define PACKET_READ_CHOMP_NEWLINE (1u<<1)
+#define PACKET_READ_GENTLE_ON_EOF     (1u<<0)
+#define PACKET_READ_CHOMP_NEWLINE     (1u<<1)
+#define PACKET_READ_DIE_ON_ERR_PACKET (1u<<2)
 int packet_read(int fd, char **src_buffer, size_t *src_len, char
 		*buffer, unsigned size, int options);
 
@@ -116,6 +121,21 @@ char *packet_read_line_buf(char **src_buf, size_t *src_len, int *size);
  */
 ssize_t read_packetized_to_strbuf(int fd_in, struct strbuf *sb_out);
 
+/*
+ * Receive multiplexed output stream over git native protocol.
+ * in_stream is the input stream from the remote, which carries data
+ * in pkt_line format with band designator.  Demultiplex it into out
+ * and err and return error appropriately.  Band #1 carries the
+ * primary payload.  Things coming over band #2 is not necessarily
+ * error; they are usually informative message on the standard error
+ * stream, aka "verbose").  A message over band #3 is a signal that
+ * the remote died unexpectedly.  A flush() concludes the stream.
+ *
+ * Returns SIDEBAND_FLUSH upon a normal conclusion, and SIDEBAND_PROTOCOL_ERROR
+ * or SIDEBAND_REMOTE_ERROR if an error occurred.
+ */
+int recv_sideband(const char *me, int in_stream, int out);
+
 struct packet_reader {
 	/* source file descriptor */
 	int fd;
@@ -142,6 +162,9 @@ struct packet_reader {
 
 	/* indicates if a line has been peeked */
 	int line_peeked;
+
+	unsigned use_sideband : 1;
+	const char *me;
 };
 
 /*
@@ -179,4 +202,19 @@ extern enum packet_read_status packet_reader_peek(struct packet_reader *reader);
 #define LARGE_PACKET_DATA_MAX (LARGE_PACKET_MAX - 4)
 extern char packet_buffer[LARGE_PACKET_MAX];
 
+struct packet_writer {
+	int dest_fd;
+	unsigned use_sideband : 1;
+};
+
+void packet_writer_init(struct packet_writer *writer, int dest_fd);
+
+/* These functions die upon failure. */
+__attribute__((format (printf, 2, 3)))
+void packet_writer_write(struct packet_writer *writer, const char *fmt, ...);
+__attribute__((format (printf, 2, 3)))
+void packet_writer_error(struct packet_writer *writer, const char *fmt, ...);
+void packet_writer_delim(struct packet_writer *writer);
+void packet_writer_flush(struct packet_writer *writer);
+
 #endif