stream: Add fileinstream support

This commit introduces a new fileinstream implementation
in the NuttX stream library.

Signed-off-by: yangao1 <yangao1@xiaomi.com>

include/nuttx/streams.h

@@ -211,6 +211,12 @@ struct lib_rawoutstream_s
   int                    fd;
 };
 
+struct lib_fileinstream_s
+{
+  struct lib_instream_s  common;
+  struct file            file;
+};
+
 struct lib_fileoutstream_s
 {
   struct lib_outstream_s common;
@@ -399,6 +405,36 @@ void lib_stdsistream(FAR struct lib_stdsistream_s *stream,
 void lib_stdsostream(FAR struct lib_stdsostream_s *stream,
                      FAR FILE *handle);
 
+/****************************************************************************
+ * Name: lib_fileinstream_open, lib_fileinstream_close,
+ *       lib_fileoutstream_open, lib_fileoutstream_close
+ *
+ * Description:
+ *   Initializes or release a file-based stream instance.
+ *   Defined in lib_fileinstream.c and lib/lib_fileoutstream.c
+ *
+ * Input Parameters:
+ *  For open:
+ *    stream  - User allocated, uninitialized instance of stream struct
+ *             to be initialized.
+ *    path    - Path to the file to be opened.
+ *    oflag   - File open flags.
+ *    mode    - File access mode.
+ *  For close:
+ *    stream  - User allocated, initialized instance of stream struct
+ * Returned Value:
+ *  open: Zero on success; a negated errno value on failure.
+ *  close: None (resource cleanup only).
+ *
+ ****************************************************************************/
+
+int lib_fileinstream_open(FAR struct lib_fileinstream_s *stream,
+                          FAR const char *path, int oflag, mode_t mode);
+void lib_fileinstream_close(FAR struct lib_fileinstream_s *stream);
+int lib_fileoutstream_open(FAR struct lib_fileoutstream_s *stream,
+                           FAR const char *path, int oflag, mode_t mode);
+void lib_fileoutstream_close(FAR struct lib_fileoutstream_s *stream);
+
 /****************************************************************************
  * Name: lib_rawinstream, lib_rawoutstream, lib_rawsistream, and
  *       lib_rawsostream,
@@ -424,8 +460,6 @@ void lib_rawinstream(FAR struct lib_rawinstream_s *stream, int fd);
 void lib_rawoutstream(FAR struct lib_rawoutstream_s *stream, int fd);
 void lib_rawsistream(FAR struct lib_rawsistream_s *stream, int fd);
 void lib_rawsostream(FAR struct lib_rawsostream_s *stream, int fd);
-void lib_fileoutstream(FAR struct lib_fileoutstream_s *stream,
-                       FAR struct file *file);
 
 /****************************************************************************
  * Name: lib_bufferedoutstream

libs/libc/stream/CMakeLists.txt

@@ -43,6 +43,7 @@ list(
   lib_bufferedoutstream.c
   lib_hexdumpstream.c
   lib_base64outstream.c
+  lib_fileinstream.c
   lib_fileoutstream.c)
 
 if(CONFIG_FILE_STREAM)

libs/libc/stream/Make.defs

@@ -29,8 +29,8 @@ CSRCS += lib_rawoutstream.c lib_rawsistream.c lib_rawsostream.c
 CSRCS += lib_zeroinstream.c lib_nullinstream.c lib_nulloutstream.c
 CSRCS += lib_mtdoutstream.c lib_libnoflush.c lib_libsnoflush.c
 CSRCS += lib_syslogstream.c lib_syslograwstream.c lib_bufferedoutstream.c
-CSRCS += lib_hexdumpstream.c lib_base64outstream.c lib_fileoutstream.c
-CSRCS += lib_mtdsostream.c
+CSRCS += lib_hexdumpstream.c lib_base64outstream.c lib_mtdsostream.c
+CSRCS += lib_fileinstream.c lib_fileoutstream.c
 
 # The remaining sources files depend upon C streams
 

libs/libc/stream/lib_fileinstream.c

@@ -0,0 +1,133 @@
+/****************************************************************************
+ * libs/libc/stream/lib_fileinstream.c
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <errno.h>
+
+#include <nuttx/fs/fs.h>
+
+#include "libc.h"
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: fileinstream_gets
+ ****************************************************************************/
+
+static ssize_t fileinstream_gets(FAR struct lib_instream_s *self,
+                                 FAR void *buf, size_t len)
+{
+  FAR struct lib_fileinstream_s *stream =
+                                (FAR struct lib_fileinstream_s *)self;
+  ssize_t nread;
+
+  do
+    {
+      nread = file_read(&stream->file, buf, len);
+    }
+  while (nread == -EINTR);
+
+  if (nread >= 0)
+    {
+      self->nget += nread;
+    }
+
+  return nread;
+}
+
+/****************************************************************************
+ * Name: fileinstream_getc
+ ****************************************************************************/
+
+static int fileinstream_getc(FAR struct lib_instream_s *self)
+{
+  unsigned char ch;
+  return fileinstream_gets(self, &ch, 1) == 1 ? ch : EOF;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: lib_fileinstream_open
+ *
+ * Description:
+ *   Initializes a stream for use with a file descriptor.
+ *
+ * Input Parameters:
+ *   stream   - User allocated, uninitialized instance of struct
+ *              lib_fileinstream_s to be initialized.
+ *
+ * Returned Value:
+ *   None (User allocated instance initialized).
+ *
+ ****************************************************************************/
+
+int lib_fileinstream_open(FAR struct lib_fileinstream_s *stream,
+                          FAR const char *path, int oflag, mode_t mode)
+{
+  int ret;
+
+  ret = file_open(&stream->file, path, oflag, mode);
+  if (ret < 0)
+    {
+      return ret;
+    }
+
+  stream->common.getc = fileinstream_getc;
+  stream->common.gets = fileinstream_gets;
+  stream->common.nget = 0;
+
+  return 0;
+}
+
+/****************************************************************************
+ * Name: lib_fileinstream_close
+ *
+ * Description:
+ *  Close the file associated with the stream.
+ *
+ * Input Parameters:
+ *   stream   - User allocated, uninitialized instance of struct
+ *              lib_fileinstream_s to be initialized.
+ *
+ * Returned Value:
+ *   None (User allocated instance initialized).
+ *
+ ****************************************************************************/
+
+void lib_fileinstream_close(FAR struct lib_fileinstream_s *stream)
+{
+  if (stream != NULL)
+    {
+      file_close(&stream->file);
+      stream->common.nget = 0;
+    }
+}