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-rw-r--r--cpukit/libfs/src/pipe/pipe.c79
1 files changed, 79 insertions, 0 deletions
diff --git a/cpukit/libfs/src/pipe/pipe.c b/cpukit/libfs/src/pipe/pipe.c
new file mode 100644
index 0000000000..63a294f5f8
--- /dev/null
+++ b/cpukit/libfs/src/pipe/pipe.c
@@ -0,0 +1,79 @@
+/*
+ * pipe.c: anonymous pipe
+ *
+ * Author: Wei Shen <cquark@gmail.com>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ *
+ * $Id$
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdio.h>
+#include <fcntl.h>
+#include <rtems/libio_.h>
+#include <rtems/seterr.h>
+
+/* Incremental number added to names of anonymous pipe files */
+/* FIXME: This approach is questionable */
+static uint16_t rtems_pipe_no = 0;
+
+/*
+ * Called by pipe() to create an anonymous pipe.
+ */
+int pipe_create(
+ int filsdes[2]
+)
+{
+ rtems_libio_t *iop;
+ int err = 0;
+
+ if (rtems_mkdir("/tmp", S_IRWXU | S_IRWXG | S_IRWXO) != 0)
+ return -1;
+
+ /* /tmp/.fifoXXXX */
+ char fifopath[15];
+ memcpy(fifopath, "/tmp/.fifo", 10);
+ sprintf(fifopath + 10, "%04x", rtems_pipe_no ++);
+
+ /* Try creating FIFO file until find an available file name */
+ while (mkfifo(fifopath, S_IRUSR|S_IWUSR) != 0) {
+ if (errno != EEXIST){
+ return -1;
+ }
+ /* Just try once... */
+ return -1;
+ /* sprintf(fifopath + 10, "%04x", rtems_pipe_no ++); */
+ }
+
+ /* Non-blocking open to avoid waiting for writers */
+ filsdes[0] = open(fifopath, O_RDONLY | O_NONBLOCK);
+ if (filsdes[0] < 0) {
+ err = errno;
+ /* Delete file at errors, or else if pipe is successfully created
+ the file node will be deleted after it is closed by all. */
+ unlink(fifopath);
+ }
+ else {
+ /* Reset open file to blocking mode */
+ iop = rtems_libio_iop(filsdes[0]);
+ iop->flags &= ~LIBIO_FLAGS_NO_DELAY;
+
+ filsdes[1] = open(fifopath, O_WRONLY);
+
+ if (filsdes[1] < 0) {
+ err = errno;
+ close(filsdes[0]);
+ }
+ unlink(fifopath);
+ }
+ if(err != 0)
+ rtems_set_errno_and_return_minus_one(err);
+ return 0;
+}
+