From: Łukasz Stelmach <l.stelmach@samsung.com>
Date: Tue, 13 Apr 2021 10:24:38 +0000 (+0200)
Subject: logger: return amount of data written to stdio
X-Git-Tag: accepted/tizen/unified/20210419.153507~3
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=0bd63d18aa6237a40912ce2cdda7a358ebf87520;p=platform%2Fkernel%2Flinux-rpi.git

logger: return amount of data written to stdio

Return amount of data written by a process to a logger via STDIO
interface.

Change-Id: I9c77a312d09f3d796a7ec64d5909af193bcc8bc2
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
---

diff --git a/drivers/staging/android/logger.c b/drivers/staging/android/logger.c
index 197b9c5..7983e57 100644
--- a/drivers/staging/android/logger.c
+++ b/drivers/staging/android/logger.c
@@ -592,7 +592,7 @@ static ssize_t logger_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	/* Prepend messages from STDOUT and STDERR with a tag and prio */
 	if (from_stdio) {
 		char *p;
-		size_t chunk_len = 0;
+		size_t chunk_len = 0, c = 0;
 		/* -2 : priority byte and tag terminating '\0' */
 		size_t max_payload = LOGGER_ENTRY_MAX_PAYLOAD - writer->tag_len - 2;
 
@@ -624,30 +624,31 @@ static ssize_t logger_write_iter(struct kiocb *iocb, struct iov_iter *from)
 		if (writer->b_owner != current && writer->b_off)
 			flush_thread_data(file);
 
+		count = 0;
 		/* -1 : leave space for message terminating '\0' */
-		count = min_t(size_t, iov_iter_count(from),
-			      max_payload - writer->b_off - 1);
+		c = min_t(size_t, iov_iter_count(from),
+			  max_payload - writer->b_off - 1);
 
 		do {
 
-			if (copy_from_iter(writer->buffer + writer->b_off, count, from) != count) {
+			if (copy_from_iter(writer->buffer + writer->b_off, c, from) != c) {
 				mutex_unlock(&log->mutex);
 				return -EFAULT;
 			}
-
+			count += c;
 			/* TODO: replace NULL characters with new lines */
-			p = strnrchr(writer->buffer + writer->b_off, count, '\n');
+			p = strnrchr(writer->buffer + writer->b_off, c, '\n');
 			if (p) {
 				*p++ = '\0';
 				chunk_len = p - writer->buffer;
 			} else {
-				writer->buffer[writer->b_off + count++] = '\0';
-				p = &writer->buffer[writer->b_off + count];
+				writer->buffer[writer->b_off + c++] = '\0';
+				p = &writer->buffer[writer->b_off + c];
 				chunk_len = p - writer->buffer;
 
 				BUG_ON(chunk_len > max_payload);
 				if (chunk_len < max_payload ) {
-					writer->b_off = writer->b_off + count - 1;
+					writer->b_off = writer->b_off + c - 1;
 					continue;
 				}
 
@@ -659,13 +660,13 @@ static ssize_t logger_write_iter(struct kiocb *iocb, struct iov_iter *from)
 			write_log_data(log, &header, writer, chunk_len);
 
 			/* move the remaining part of the message */
-			memmove(writer->buffer, p, writer->b_off + count - chunk_len);
+			memmove(writer->buffer, p, writer->b_off + c - chunk_len);
 
 			/* new b_off points where the rimainder of the string ends */
-			writer->b_off = writer->b_off + count - chunk_len;
+			writer->b_off = writer->b_off + c - chunk_len;
 			writer->buffer[writer->b_off] = '\0';
 
-		} while ((count = min_t(size_t, iov_iter_count(from), max_payload - 1)));
+		} while ((c = min_t(size_t, iov_iter_count(from), max_payload - 1)));
 
 		/* save for remaining unfinished line */
 		writer->b_header = header;