git/list[1] front-page[2] threads[3] people[4] search[5] about
 

Re: [PATCH v6 3/8] convert: Split start_multi_file_filter into two separate functions

From
Junio C Hamano <gitster@pobox.com>
Date
Apr 24, 2017, 04:31 UTC
Message-ID
<xmqqshkyzask.fsf@gitster.mtv.corp.google.com>
In-Reply-To
<20170421172611.12152-4-benpeart@microsoft.com>
Ben Peart <peartben@gmail.com> writes:
> Subject: [PATCH v6 3/8] convert: Split start_multi_file_filter into two separate functions

Two minor nits, because the capital after "<area>:" looks ugly in shortlog output, and having () there makes it easier to notice that a function name is being discussed. I.e.

    convert: split start_multi_file_filter() into two separate functions
Show 9 quoted lines
> 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.

The above fails to describe a lot more important/significant change this patch makes. Two mistaken check "errno == EPIPE" have been removed as a preliminary bugfix. I think the bugfix deserves to be split into a separate patch by itself and hoisted much earlier in the series. It alone is a very good change, with or without the remainder of the changes in this patch.

Thanks.
Show 97 quoted lines
> Signed-off-by: Ben Peart <benpeart@microsoft.com>
> ---
>  convert.c | 62 ++++++++++++++++++++++++++++++++++++--------------------------
>  1 file changed, 36 insertions(+), 26 deletions(-)
>
> diff --git a/convert.c b/convert.c
> index 793c29ebfd..36401fe087 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 +621,38 @@ static struct cmd2process *start_multi_file_filter(struct hashmap *hashmap, cons
>  done:
>  	sigchain_pop(SIGPIPE);
>  
> -	if (err || errno == EPIPE) {
> +	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;
> @@ -733,7 +743,7 @@ static int apply_multi_file_filter(const char *path, const char *src, size_t len
>  done:
>  	sigchain_pop(SIGPIPE);
>  
> -	if (err || errno == EPIPE) {
> +	if (err) {
>  		if (!strcmp(filter_status.buf, "error")) {
>  			/* The filter signaled a problem with the file. */
>  		} else if (!strcmp(filter_status.buf, "abort")) {
Previous: Ben PeartNext: Ben Peart
Message 3 of 15 in “refactor the filter process code into a reusable module”
  1. 0/8 refactor the filter process code into a reusable moduleBen Peart, Apr 21, 2017
  2. 3/8 convert: Split start_multi_file_filter into two separate functionsBen Peart, Apr 21, 2017
  3. Junio C HamanoApr 24, 2017
  4. Ben PeartApr 24, 2017
  5. 1/8 pkt-line: add packet_read_line_gently()Ben Peart, Apr 21, 2017
  6. Junio C HamanoApr 24, 2017
  7. Ben PeartApr 24, 2017
  8. Junio C HamanoApr 25, 2017
  9. Ben PeartApr 25, 2017
  10. 4/8 convert: Separate generic structures and variables from the filter specific onesBen Peart, Apr 21, 2017
  11. 7/8 sub-process: move sub-process functions into separate filesBen Peart, Apr 21, 2017
  12. 6/8 convert: rename reusable sub-process functionsBen Peart, Apr 21, 2017
  13. 5/8 convert: Update generic functions to only use generic data structuresBen Peart, Apr 21, 2017
  14. 8/8 convert: Update subprocess_read_status to not die on EOFBen Peart, Apr 21, 2017
  15. 2/8 convert: move packet_write_list() into pkt-line as packet_writel()Ben Peart, Apr 21, 2017

Read the whole thread, see it on lore, or plain text.

$ cat FOOTERMessages come from the public archive at lore.kernel.org/git, fetched every hour. The front page is chosen and written each morning by an AI editor and can be wrong; the threads themselves are the record. About and API. For agents: an MCP server at https://gitlist.dev/mcp, and any thread, story or person page as Markdown by adding .md to its URL (or sending Accept: text/markdown). Details in /llms.txt.