Re: [PATCH v5 3/8] convert: Split start_multi_file_filter into two separate functions

> On 07 Apr 2017, at 14:03, Ben Peart <peartben@gmail.com> wrote:
> 
> To enable future reuse of the filter.<driver>.process infrastructure,
> split start_multi_file_filter into two separate parts.
> 
> start_multi_file_filter will now only contain the generic logic to
> manage the creation and tracking of the child process in a hashmap.
> 
> start_multi_file_filter_fn is a protocol specific initialization
> function that will negotiate the multi-file-filter interface version
> and capabilities.
> 
> Signed-off-by: Ben Peart <benpeart@microsoft.com>
> ---
> convert.c | 63 ++++++++++++++++++++++++++++++++++++++-------------------------
> 1 file changed, 38 insertions(+), 25 deletions(-)
> 
> diff --git a/convert.c b/convert.c
> index 793c29ebfd..404757eac9 100644
> --- a/convert.c
> +++ b/convert.c
> @@ -565,35 +565,14 @@ static void stop_multi_file_filter(struct child_process *process)
> 	finish_command(process);
> }
> 
> -static struct cmd2process *start_multi_file_filter(struct hashmap *hashmap, const char *cmd)
> +static int start_multi_file_filter_fn(struct cmd2process *entry)
> {
> 	int err;
> -	struct cmd2process *entry;
> -	struct child_process *process;
> -	const char *argv[] = { cmd, NULL };
> 	struct string_list cap_list = STRING_LIST_INIT_NODUP;
> 	char *cap_buf;
> 	const char *cap_name;
> -
> -	entry = xmalloc(sizeof(*entry));
> -	entry->cmd = cmd;
> -	entry->supported_capabilities = 0;
> -	process = &entry->process;
> -
> -	child_process_init(process);
> -	process->argv = argv;
> -	process->use_shell = 1;
> -	process->in = -1;
> -	process->out = -1;
> -	process->clean_on_exit = 1;
> -	process->clean_on_exit_handler = stop_multi_file_filter;
> -
> -	if (start_command(process)) {
> -		error("cannot fork to run external filter '%s'", cmd);
> -		return NULL;
> -	}
> -
> -	hashmap_entry_init(entry, strhash(cmd));
> +	struct child_process *process = &entry->process;
> +	const char *cmd = entry->cmd;
> 
> 	sigchain_push(SIGPIPE, SIG_IGN);
> 
> @@ -642,7 +621,41 @@ static struct cmd2process *start_multi_file_filter(struct hashmap *hashmap, cons
> done:
> 	sigchain_pop(SIGPIPE);
> 
> -	if (err || errno == EPIPE) {
> +	if (err || errno == EPIPE)
> +		err = err ? err : errno;

> +
> +	return err;
> +}
> +
> +static struct cmd2process *start_multi_file_filter(struct hashmap *hashmap, const char *cmd)
> +{
> +	int err;
> +	struct cmd2process *entry;
> +	struct child_process *process;
> +	const char *argv[] = { cmd, NULL };
> +
> +	entry = xmalloc(sizeof(*entry));
> +	entry->cmd = cmd;
> +	entry->supported_capabilities = 0;
> +	process = &entry->process;
> +
> +	child_process_init(process);
> +	process->argv = argv;
> +	process->use_shell = 1;
> +	process->in = -1;
> +	process->out = -1;
> +	process->clean_on_exit = 1;
> +	process->clean_on_exit_handler = stop_multi_file_filter;
> +
> +	if (start_command(process)) {
> +		error("cannot fork to run external filter '%s'", cmd);
> +		return NULL;
> +	}
> +
> +	hashmap_entry_init(entry, strhash(cmd));
> +
> +	err = start_multi_file_filter_fn(entry);
> +	if (err) {
> 		error("initialization for external filter '%s' failed", cmd);
> 		kill_multi_file_filter(hashmap, entry);
> 		return NULL;
> -- 
> 2.12.0.windows.1.31.g1548525701.dirty