job: Add error message for failing jobs

So far we relied on job->ret and strerror() to produce an error message
for failed jobs. Not surprisingly, this tends to result in completely
useless messages.

This adds a Job.error field that can contain an error string for a
failing job, and a parameter to job_completed() that sets the field. As
a default, if NULL is passed, we continue to use strerror(job->ret).

All existing callers are changed to pass NULL. They can be improved in
separate patches.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>

1 files changed, 2 insertions, 7 deletions

diff --git a/job-qmp.c b/job-qmp.c
index 7f38f63336..410775df61 100644
--- a/job-qmp.c
+++ b/job-qmp.c
@@ -136,14 +136,9 @@ void qmp_job_dismiss(const char *id, Error **errp)
 static JobInfo *job_query_single(Job *job, Error **errp)
 {
     JobInfo *info;
-    const char *errmsg = NULL;
 
     assert(!job_is_internal(job));
 
-    if (job->ret < 0) {
-        errmsg = strerror(-job->ret);
-    }
-
     info = g_new(JobInfo, 1);
     *info = (JobInfo) {
         .id                 = g_strdup(job->id),
@@ -151,8 +146,8 @@ static JobInfo *job_query_single(Job *job, Error **errp)
         .status             = job->status,
         .current_progress   = job->progress_current,
         .total_progress     = job->progress_total,
-        .has_error          = !!errmsg,
-        .error              = g_strdup(errmsg),
+        .has_error          = !!job->error,
+        .error              = g_strdup(job->error),
     };
 
     return info;