sideband: diagnose more sideband anomalies

[thirdparty/git.git] / sideband.c

diff --git a/sideband.c b/sideband.c
index e337d76e80f91c95e2be72d7e8cfe62a49dfcfdb..81daddeb54951fa550c6fca3f2e85cb9cf4297b7 100644 (file)
--- a/sideband.c
+++ b/sideband.c
@@ -3,6 +3,7 @@
 #include "config.h"
 #include "sideband.h"
 #include "help.h"
+#include "pkt-line.h"
 
 struct keyword_entry {
        /*
@@ -114,7 +115,8 @@ static void maybe_colorize_sideband(struct strbuf *dest, const char *src, int n)
 #define ANSI_SUFFIX "\033[K"
 #define DUMB_SUFFIX "        "
 
-int demultiplex_sideband(const char *me, char *buf, int len,
+int demultiplex_sideband(const char *me, int status,
+                        char *buf, int len,
                         int die_on_error,
                         struct strbuf *scratch,
                         enum sideband_type *sideband_type)
@@ -130,17 +132,30 @@ int demultiplex_sideband(const char *me, char *buf, int len,
                        suffix = DUMB_SUFFIX;
        }
 
-       if (len == 0) {
-               *sideband_type = SIDEBAND_FLUSH;
-               goto cleanup;
-       }
-       if (len < 1) {
+       if (status == PACKET_READ_EOF) {
                strbuf_addf(scratch,
-                           "%s%s: protocol error: no band designator",
+                           "%s%s: unexpected disconnect while reading sideband packet",
                            scratch->len ? "\n" : "", me);
                *sideband_type = SIDEBAND_PROTOCOL_ERROR;
                goto cleanup;
        }
+
+       if (len < 0)
+               BUG("negative length on non-eof packet read");
+
+       if (len == 0) {
+               if (status == PACKET_READ_NORMAL) {
+                       strbuf_addf(scratch,
+                                   "%s%s: protocol error: missing sideband designator",
+                                   scratch->len ? "\n" : "", me);
+                       *sideband_type = SIDEBAND_PROTOCOL_ERROR;
+               } else {
+                       /* covers flush, delim, etc */
+                       *sideband_type = SIDEBAND_FLUSH;
+               }
+               goto cleanup;
+       }
+
        band = buf[0] & 0xff;
        buf[len] = '\0';
        len--;