Re: [PATCH Nix] Flush substituter output upon ‘\r’

[Ludovic Courtès]

Hi,

Please use reply-to-all.

Eelco Dolstra <address@hidden> skribis:

> On 17/06/14 17:50, Ludovic Courtès wrote:
>
>> The patch below changes the store so that it flushes what it reads from
>> the substituter’s stderr when it encounters either a newline or a
>> carriage return.
>> 
>> The intent is to allow substituters to provide some kind of progress
>> report, where the status is updated by means of a ‘\r’.
>
> What kind of progress report do you mean, and why wouldn't '\n' work for that?

Progress reports:

    0%\r
    1%\r
    2%\r

>> As a side effect, this patch removes the “substituter-name: ” prefix on
>> the lines that are printed.  It can be reinstated if deemed appropriate.
>
> Please do, without it there is no indication where the error came from.

Here it is.

Thanks,
Ludo’.

diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc
index 1293a6e..079972c 100644
--- a/src/libstore/local-store.cc
+++ b/src/libstore/local-store.cc
@@ -1141,8 +1141,10 @@ string 
LocalStore::getLineFromSubstituter(RunningSubstituter & run)
             if (n == 0) throw EndOfFile(format("substituter `%1%' died 
unexpectedly") % run.program);
             err.append(buf, n);
             string::size_type p;
-            while ((p = err.find('\n')) != string::npos) {
-                printMsg(lvlError, run.program + ": " + string(err, 0, p));
+            while (((p = err.find('\n')) != string::npos)
+                  || ((p = err.find('\r')) != string::npos)) {
+               string thing(err, 0, p + 1);
+               writeToStderr(run.program + ": " + thing);
                 err = string(err, p + 1);
             }
         }