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[PATCH v6 8/8] convert: Update subprocess_read_status to not die on EOF

From
Ben Peart <peartben@gmail.com>
Date
Apr 21, 2017, 17:26 UTC
Message-ID
<20170421172611.12152-9-benpeart@microsoft.com>
In-Reply-To
<20170421172611.12152-1-benpeart@microsoft.com>

Enable sub-processes to gracefully handle when the process dies by updating subprocess_read_status to return an error on EOF instead of dying.

Update apply_multi_file_filter to take advantage of the revised subprocess_read_status.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
---
 convert.c     | 10 ++++++++--
 sub-process.c | 10 +++++++---
 sub-process.h |  2 +-
 3 files changed, 16 insertions(+), 6 deletions(-)
diff --git a/convert.c b/convert.c
index 79d04907a5..f1e168bc30 100644
--- a/convert.c
+++ b/convert.c
@@ -635,7 +635,10 @@ static int apply_multi_file_filter(const char *path, const char *src, size_t len
 	if (err)
 		goto done;
 
-	subprocess_read_status(process->out, &filter_status);
+	err = subprocess_read_status(process->out, &filter_status);
+	if (err)
+		goto done;
+
 	err = strcmp(filter_status.buf, "success");
 	if (err)
 		goto done;
@@ -644,7 +647,10 @@ static int apply_multi_file_filter(const char *path, const char *src, size_t len
 	if (err)
 		goto done;
 
-	subprocess_read_status(process->out, &filter_status);
+	err = subprocess_read_status(process->out, &filter_status);
+	if (err)
+		goto done;
+
 	err = strcmp(filter_status.buf, "success");
 
 done:
diff --git a/sub-process.c b/sub-process.c
index 536b60cced..92f8aea70a 100644
--- a/sub-process.c
+++ b/sub-process.c
@@ -21,13 +21,15 @@ struct subprocess_entry *subprocess_find_entry(struct hashmap *hashmap, const ch
 	return hashmap_get(hashmap, &key, NULL);
 }
 
-void subprocess_read_status(int fd, struct strbuf *status)
+int subprocess_read_status(int fd, struct strbuf *status)
 {
 	struct strbuf **pair;
 	char *line;
+	int len;
+
 	for (;;) {
-		line = packet_read_line(fd, NULL);
-		if (!line)
+		len = packet_read_line_gently(fd, NULL, &line);
+		if ((len < 0) || !line)
 			break;
 		pair = strbuf_split_str(line, '=', 2);
 		if (pair[0] && pair[0]->len && pair[1]) {
@@ -39,6 +41,8 @@ void subprocess_read_status(int fd, struct strbuf *status)
 		}
 		strbuf_list_free(pair);
 	}
+
+	return (len < 0) ? len : 0;
 }
 
 void subprocess_stop(struct hashmap *hashmap, struct subprocess_entry *entry)
diff --git a/sub-process.h b/sub-process.h
index a88e782bfc..7d451e1cde 100644
--- a/sub-process.h
+++ b/sub-process.h
@@ -44,6 +44,6 @@ static inline struct child_process *subprocess_get_child_process(
  * key/value pairs and return the value from the last "status" packet
  */
 
-void subprocess_read_status(int fd, struct strbuf *status);
+int subprocess_read_status(int fd, struct strbuf *status);
 
 #endif
-- 
2.12.0.windows.1.33.g243d9b384c
Previous: Ben PeartNext: Ben Peart
Message 14 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

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