From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Mon, 5 Aug 2013 17:46:58 +0000 (-0400)
Subject: Fix: kernel ctl error codes are based on errno
X-Git-Tag: v2.2.4~25
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=da3d1b707e026be8fd7f4f133e729890c7dc3653;p=lttng-tools.git

Fix: kernel ctl error codes are based on errno

ioctl returns -1, and error codes are based on -errno.

Signed-off-by: Julien Desfossez <jdesfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/src/common/consumer.c b/src/common/consumer.c
index 912988977..e77453210 100644
--- a/src/common/consumer.c
+++ b/src/common/consumer.c
@@ -1367,6 +1367,7 @@ ssize_t lttng_consumer_on_read_subbuffer_mmap(
 	if (stream->net_seq_idx != (uint64_t) -1ULL) {
 		relayd = consumer_find_relayd(stream->net_seq_idx);
 		if (relayd == NULL) {
+			ret = -EPIPE;
 			goto end;
 		}
 	}
@@ -1376,28 +1377,31 @@ ssize_t lttng_consumer_on_read_subbuffer_mmap(
 	case LTTNG_CONSUMER_KERNEL:
 		mmap_base = stream->mmap_base;
 		ret = kernctl_get_mmap_read_offset(stream->wait_fd, &mmap_offset);
+		if (ret != 0) {
+			PERROR("tracer ctl get_mmap_read_offset");
+			written = -errno;
+			goto end;
+		}
 		break;
 	case LTTNG_CONSUMER32_UST:
 	case LTTNG_CONSUMER64_UST:
 		mmap_base = lttng_ustctl_get_mmap_base(stream);
 		if (!mmap_base) {
 			ERR("read mmap get mmap base for stream %s", stream->name);
-			written = -1;
+			written = -EPERM;
 			goto end;
 		}
 		ret = lttng_ustctl_get_mmap_read_offset(stream, &mmap_offset);
-
+		if (ret != 0) {
+			PERROR("tracer ctl get_mmap_read_offset");
+			written = ret;
+			goto end;
+		}
 		break;
 	default:
 		ERR("Unknown consumer_data type");
 		assert(0);
 	}
-	if (ret != 0) {
-		errno = -ret;
-		PERROR("tracer ctl get_mmap_read_offset");
-		written = ret;
-		goto end;
-	}
 
 	/* Handle stream on the relayd if the output is on the network */
 	if (relayd) {
@@ -1478,7 +1482,7 @@ ssize_t lttng_consumer_on_read_subbuffer_mmap(
 			 */
 			DBG("Error in file write mmap");
 			if (written == 0) {
-				written = ret;
+				written = -errno;
 			}
 			/* Socket operation failed. We consider the relayd dead */
 			if (errno == EPIPE || errno == EINVAL) {
@@ -1566,6 +1570,7 @@ ssize_t lttng_consumer_on_read_subbuffer_splice(
 	if (stream->net_seq_idx != (uint64_t) -1ULL) {
 		relayd = consumer_find_relayd(stream->net_seq_idx);
 		if (relayd == NULL) {
+			ret = -EPIPE;
 			goto end;
 		}
 	}
diff --git a/src/common/kernel-consumer/kernel-consumer.c b/src/common/kernel-consumer/kernel-consumer.c
index 1a44ce152..ea6237959 100644
--- a/src/common/kernel-consumer/kernel-consumer.c
+++ b/src/common/kernel-consumer/kernel-consumer.c
@@ -56,8 +56,8 @@ int lttng_kconsumer_take_snapshot(struct lttng_consumer_stream *stream)
 
 	ret = kernctl_snapshot(infd);
 	if (ret != 0) {
-		errno = -ret;
 		perror("Getting sub-buffer snapshot.");
+		ret = -errno;
 	}
 
 	return ret;
@@ -76,8 +76,8 @@ int lttng_kconsumer_get_produced_snapshot(struct lttng_consumer_stream *stream,
 
 	ret = kernctl_snapshot_get_produced(infd, pos);
 	if (ret != 0) {
-		errno = -ret;
 		perror("kernctl_snapshot_get_produced");
+		ret = -errno;
 	}
 
 	return ret;
@@ -452,7 +452,6 @@ ssize_t lttng_kconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
 	/* Get the next subbuffer */
 	err = kernctl_get_next_subbuf(infd);
 	if (err != 0) {
-		ret = err;
 		/*
 		 * This is a debug message even for single-threaded consumer,
 		 * because poll() have more relaxed criterions than get subbuf,
@@ -461,15 +460,15 @@ ssize_t lttng_kconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
 		 */
 		DBG("Reserving sub buffer failed (everything is normal, "
 				"it is due to concurrency)");
+		ret = -errno;
 		goto end;
 	}
 
 	/* Get the full subbuffer size including padding */
 	err = kernctl_get_padded_subbuf_size(infd, &len);
 	if (err != 0) {
-		errno = -err;
 		perror("Getting sub-buffer len failed.");
-		ret = err;
+		ret = -errno;
 		goto end;
 	}
 
@@ -504,9 +503,8 @@ ssize_t lttng_kconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
 		/* Get subbuffer size without padding */
 		err = kernctl_get_subbuf_size(infd, &subbuf_size);
 		if (err != 0) {
-			errno = -err;
 			perror("Getting sub-buffer len failed.");
-			ret = err;
+			ret = -errno;
 			goto end;
 		}
 
@@ -536,20 +534,18 @@ ssize_t lttng_kconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
 		break;
 	default:
 		ERR("Unknown output method");
-		ret = -1;
+		ret = -EPERM;
 	}
 
 	err = kernctl_put_next_subbuf(infd);
 	if (err != 0) {
-		errno = -err;
 		if (errno == EFAULT) {
 			perror("Error in unreserving sub buffer\n");
 		} else if (errno == EIO) {
 			/* Should never happen with newer LTTng versions */
 			perror("Reader has been pushed by the writer, last sub-buffer corrupted.");
 		}
-
-		ret = -err;
+		ret = -errno;
 		goto end;
 	}
 
@@ -581,8 +577,8 @@ int lttng_kconsumer_on_recv_stream(struct lttng_consumer_stream *stream)
 
 		ret = kernctl_get_mmap_len(stream->wait_fd, &mmap_len);
 		if (ret != 0) {
-			errno = -ret;
 			PERROR("kernctl_get_mmap_len");
+			ret = -errno;
 			goto error_close_fd;
 		}
 		stream->mmap_len = (size_t) mmap_len;