fix: write EINTR handling

[lttng-tools.git] / src / common / kernel-consumer / kernel-consumer.c

diff --git a/src/common/kernel-consumer/kernel-consumer.c b/src/common/kernel-consumer/kernel-consumer.c
index 8ed279f44e16db7e73a14d8947c9e87b143f6946..00bb7f7212cac7f0ccf4f4a6c91ef80dbb4b58ef 100644 (file)
--- a/src/common/kernel-consumer/kernel-consumer.c
+++ b/src/common/kernel-consumer/kernel-consumer.c
@@ -101,12 +101,12 @@ ssize_t lttng_kconsumer_on_read_subbuffer_mmap(
                                do {
                                        ret = write(outfd, (void *) &metadata_id,
                                                        sizeof(stream->relayd_stream_id));
-                                       if (ret < 0) {
-                                               PERROR("write metadata stream id");
-                                               written = ret;
-                                               goto end;
-                                       }
-                               } while (errno == EINTR);
+                               } while (ret < 0 && errno == EINTR);
+                               if (ret < 0) {
+                                       PERROR("write metadata stream id");
+                                       written = ret;
+                                       goto end;
+                               }
                                DBG("Metadata stream id %zu written before data",
                                                stream->relayd_stream_id);
                                /*
@@ -120,18 +120,15 @@ ssize_t lttng_kconsumer_on_read_subbuffer_mmap(
        }
 
        while (len > 0) {
-               ret = write(outfd, stream->mmap_base + mmap_offset, len);
+               do {
+                       ret = write(outfd, stream->mmap_base + mmap_offset, len);
+               } while (ret < 0 && errno == EINTR);
                if (ret < 0) {
-                       if (errno == EINTR) {
-                               /* restart the interrupted system call */
-                               continue;
-                       } else {
-                               perror("Error in file write");
-                               if (written == 0) {
-                                       written = ret;
-                               }
-                               goto end;
+                       perror("Error in file write");
+                       if (written == 0) {
+                               written = ret;
                        }
+                       goto end;
                } else if (ret > len) {
                        perror("Error in file write");
                        written += ret;
@@ -200,17 +197,17 @@ ssize_t lttng_kconsumer_on_read_subbuffer_splice(
                 */
                pthread_mutex_lock(&relayd->ctrl_sock_mutex);
 
+               metadata_id = htobe64(stream->relayd_stream_id);
                do {
-                       metadata_id = htobe64(stream->relayd_stream_id);
                        ret = write(ctx->consumer_thread_pipe[1],
                                        (void *) &metadata_id,
                                        sizeof(stream->relayd_stream_id));
-                       if (ret < 0) {
-                               PERROR("write metadata stream id");
-                               written = ret;
-                               goto end;
-                       }
-               } while (errno == EINTR);
+               } while (ret < 0 && errno == EINTR);
+               if (ret < 0) {
+                       PERROR("write metadata stream id");
+                       written = ret;
+                       goto end;
+               }
                DBG("Metadata stream id %zu written before data",
                                stream->relayd_stream_id);
        }
@@ -581,7 +578,7 @@ end:
         */
        do {
                ret = write(ctx->consumer_poll_pipe[1], "", 1);
-       } while (ret == -1UL && errno == EINTR);
+       } while (ret < 0 && errno == EINTR);
 end_nosignal:
        return 0;
 }