sub-process: print the cmd when a capability is unsupported

In handshake_capabilities() we use warning() when a capability
is not supported, so the exit code of the function is 0 and no
further error is shown. This is a problem because the warning
message doesn't tell us which subprocess cmd failed.

On the contrary if we cannot write a packet from this function,
we use error() and then subprocess_start() outputs:

initialization for subprocess '<cmd>' failed

so we can know which subprocess cmd failed.

Let's improve the warning() message, so that we can know which
subprocess cmd failed.

Helped-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/sub-process.c b/sub-process.c
index 86de8d7bfbcd781b50571f867f0669c84093eca3..fcc4832c14f3fdbb41bea12142a8fbf167d2aa55 100644 (file)
--- a/sub-process.c
+++ b/sub-process.c
@@ -181,8 +181,8 @@ static int handshake_capabilities(struct child_process *process,
                        if (supported_capabilities)
                                *supported_capabilities |= capabilities[i].flag;
                } else {
-                       warning("external filter requested unsupported filter capability '%s'",
-                               p);
+                       warning("subprocess '%s' requested unsupported capability '%s'",
+                               process->argv[0], p);
                }
        }