[PATCHv4 3/5] run-command: add {run,start,finish}_command_or_die

[Stefan Beller]

In a later patch we want to report the exact command that we run in the
error message. Add a convenient way to the run command API that runs the
given command or reports the exact command as failure.

Signed-off-by: Stefan Beller <sbel...@google.com>
---
 run-command.c | 28 ++++++++++++++++++++++++++++
 run-command.h |  4 ++++
 2 files changed, 32 insertions(+)

diff --git a/run-command.c b/run-command.c
index ca905a9e80..a0587db334 100644
--- a/run-command.c
+++ b/run-command.c
@@ -279,6 +279,17 @@ static int wait_or_whine(pid_t pid, const char *argv0, int 
in_signal)
        return code;
 }
 
+static void report_and_die(struct child_process *cmd, const char *action)
+{
+       int i;
+       struct strbuf err = STRBUF_INIT;
+       if (cmd->git_cmd)
+               strbuf_addstr(&err, "git ");
+       for (i = 0; cmd->argv[i]; )
+               strbuf_addf(&err, "'%s'", cmd->argv[i]);
+       die(_("could not %s %s"), action, err.buf);
+}
+
 int start_command(struct child_process *cmd)
 {
        int need_in, need_out, need_err;
@@ -546,6 +557,12 @@ int start_command(struct child_process *cmd)
        return 0;
 }
 
+void start_command_or_die(struct child_process *cmd)
+{
+       if (start_command(cmd))
+               report_and_die(cmd, "start");
+}
+
 int finish_command(struct child_process *cmd)
 {
        int ret = wait_or_whine(cmd->pid, cmd->argv[0], 0);
@@ -558,6 +575,11 @@ int finish_command_in_signal(struct child_process *cmd)
        return wait_or_whine(cmd->pid, cmd->argv[0], 1);
 }
 
+void finish_command_or_die(struct child_process *cmd)
+{
+       if (finish_command(cmd))
+               report_and_die(cmd, "finish");
+}
 
 int run_command(struct child_process *cmd)
 {
@@ -592,6 +614,12 @@ int run_command_v_opt_cd_env(const char **argv, int opt, 
const char *dir, const
        return run_command(&cmd);
 }
 
+void run_command_or_die(struct child_process *cmd)
+{
+       if (finish_command(cmd))
+               report_and_die(cmd, "run");
+}
+
 #ifndef NO_PTHREADS
 static pthread_t main_thread;
 static int main_thread_set;
diff --git a/run-command.h b/run-command.h
index dd1c78c28d..e4585885c5 100644
--- a/run-command.h
+++ b/run-command.h
@@ -56,6 +56,10 @@ int finish_command(struct child_process *);
 int finish_command_in_signal(struct child_process *);
 int run_command(struct child_process *);
 
+void start_command_or_die(struct child_process *);
+void finish_command_or_die(struct child_process *);
+void run_command_or_die(struct child_process *);
+
 /*
  * Returns the path to the hook file, or NULL if the hook is missing
  * or disabled. Note that this points to static storage that will be
-- 
2.11.0.rc2.53.gb7b3fba.dirty