Cygwin: Pass file paths instead of file descriptors over UNIX sockets

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

diff --git a/src/common/ust-consumer/ust-consumer.c b/src/common/ust-consumer/ust-consumer.c
index 2b55fd4637ead2b056fcafecc47ef5504d7c5df5..97b890bf25340ba885f65a5c394d74de187126dd 100644 (file)
--- a/src/common/ust-consumer/ust-consumer.c
+++ b/src/common/ust-consumer/ust-consumer.c
@@ -49,7 +49,7 @@ ssize_t lttng_ustconsumer_on_read_subbuffer_mmap(
                struct lttng_consumer_stream *stream, unsigned long len)
 {
        unsigned long mmap_offset;
-       long ret = 0;
+       long ret = 0, written = 0;
        off_t orig_offset = stream->out_fd_offset;
        int outfd = stream->out_fd;
 
@@ -59,29 +59,39 @@ ssize_t lttng_ustconsumer_on_read_subbuffer_mmap(
        if (ret != 0) {
                errno = -ret;
                PERROR("ustctl_get_mmap_read_offset");
+               written = ret;
                goto end;
        }
        while (len > 0) {
                ret = write(outfd, stream->mmap_base + mmap_offset, len);
-               if (ret >= len) {
-                       len = 0;
-               } else if (ret < 0) {
-                       errno = -ret;
+               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;
+                       }
+               } else if (ret > len) {
                        PERROR("Error in file write");
+                       written += ret;
                        goto end;
+               } else {
+                       len -= ret;
+                       mmap_offset += ret;
                }
                /* This won't block, but will start writeout asynchronously */
                lttng_sync_file_range(outfd, stream->out_fd_offset, ret,
                                SYNC_FILE_RANGE_WRITE);
                stream->out_fd_offset += ret;
+               written += ret;
        }
-
        lttng_consumer_sync_trace_file(stream, orig_offset);
-
-       goto end;
-
 end:
-       return ret;
+       return written;
 }
 
 /*
@@ -157,18 +167,38 @@ int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
        {
                struct lttng_consumer_channel *new_channel;
                int fds[1];
-               size_t nb_fd = 1;
+               char *path;
 
                /* block */
                if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) {
                        return -EINTR;
                }
-               ret = lttcomm_recv_fds_unix_sock(sock, fds, nb_fd);
-               if (ret != sizeof(fds)) {
+
+               path = lttcomm_recv_string(sock);
+
+               if (!path) {
                        lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD);
-                       return ret;
+                       return -1;
+               }
+
+               DBG("consumer_add_channel received path %s", path);
+
+               fds[0] = open(path, O_RDWR);
+
+               if (fds[0] < 0) {
+                       DBG("consumer_add_channel open error on path %s", path);
+                       free(path);
+                       return -1;
                }
 
+               if (fcntl(fds[0], F_SETFD, FD_CLOEXEC) < 0) {
+                       DBG("consumer_add_channel fcntl error");
+                       free(path);
+                       return -1;
+               }
+
+               free(path);
+
                DBG("consumer_add_channel %d", msg.u.channel.channel_key);
 
                new_channel = consumer_allocate_channel(msg.u.channel.channel_key,
@@ -194,17 +224,59 @@ int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
        case LTTNG_CONSUMER_ADD_STREAM:
        {
                struct lttng_consumer_stream *new_stream;
-               int fds[2];
-               size_t nb_fd = 2;
+               int fds[2], i;
+               char *shm_path, *wait_pipe_path;
 
                /* block */
                if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) {
                        return -EINTR;
                }
-               ret = lttcomm_recv_fds_unix_sock(sock, fds, nb_fd);
-               if (ret != sizeof(fds)) {
+
+               shm_path = lttcomm_recv_string(sock);
+
+               if (!shm_path) {
+                       lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD);
+                       return -1;
+               }
+
+               wait_pipe_path = lttcomm_recv_string(sock);
+
+               if (!wait_pipe_path) {
                        lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD);
-                       return ret;
+                       free(shm_path);
+                       return -1;
+               }
+
+               DBG("consumer_add_stream received path %s", shm_path);
+               DBG("consumer_add_stream received path %s", wait_pipe_path);
+
+               fds[0] = open(shm_path, O_RDWR);
+
+               if (fds[0] < 0) {
+                       DBG("consumer_add_stream open error on path %s", shm_path);
+                       free(shm_path);
+                       free(wait_pipe_path);
+                       return -1;
+               }
+
+               fds[1] = open(wait_pipe_path, O_RDONLY);
+
+               if (fds[1] < 0) {
+                       DBG("consumer_add_stream open error on path %s", wait_pipe_path);
+                       PERROR("open");
+                       free(shm_path);
+                       free(wait_pipe_path);
+                       return -1;
+               }
+
+               free(shm_path);
+               free(wait_pipe_path);
+
+               for (i = 0; i < 2; ++i) {
+                       if (fcntl(fds[i], F_SETFD, FD_CLOEXEC) < 0) {
+                               DBG("consumer_add_stream fcntl error");
+                               return -1;
+                       }
                }
 
                DBG("consumer_add_stream %s (%d,%d)", msg.u.stream.path_name,
@@ -272,7 +344,12 @@ end:
                ret = write(ctx->consumer_poll_pipe[1], "", 1);
        } while (ret == -1UL && errno == EINTR);
 end_nosignal:
-       return 0;
+
+       /*
+        * Return 1 to indicate success since the 0 value can be a socket shutdown
+        * during the recv() or send() call.
+        */
+       return 1;
 }
 
 int lttng_ustconsumer_allocate_channel(struct lttng_consumer_channel *chan)
@@ -384,7 +461,7 @@ int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
        assert(err == 0);
        /* write the subbuffer to the tracefile */
        ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len);
-       if (ret < 0) {
+       if (ret != len) {
                /*
                 * display the error but continue processing to try
                 * to release the subbuffer