zhang boie / mbed-dev-f30333

mbed-dev-f303

platform/DirHandle.h@0:bdf663c61a82, 2022-06-14 (annotated)

Committer:
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4
Date:
Tue Jun 14 09:21:18 2022 +0000
Revision:
0:bdf663c61a82
lib

Who changed what in which revision?

UserRevisionLine numberNew contents of line
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 1 /* mbed Microcontroller Library
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 2 * Copyright (c) 2006-2013 ARM Limited
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 3 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 4 * Licensed under the Apache License, Version 2.0 (the "License");
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 5 * you may not use this file except in compliance with the License.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 6 * You may obtain a copy of the License at
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 7 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 8 * http://www.apache.org/licenses/LICENSE-2.0
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 9 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 10 * Unless required by applicable law or agreed to in writing, software
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 11 * distributed under the License is distributed on an "AS IS" BASIS,
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 13 * See the License for the specific language governing permissions and
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 14 * limitations under the License.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 15 */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 16 #ifndef MBED_DIRHANDLE_H
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 17 #define MBED_DIRHANDLE_H
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 18
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 19 #include <stdint.h>
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 20 #include "platform/platform.h"
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 21 #include "platform/FileHandle.h"
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 22 #include "platform/NonCopyable.h"
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 23
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 24 namespace mbed {
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 25 /** \addtogroup platform */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 26
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 27
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 28 /** Represents a directory stream. Objects of this type are returned
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 29 * by an opendir function. The core functions are read and seek,
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 30 * but only a subset needs to be provided.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 31 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 32 * If a FileSystemLike class defines the opendir method, then the
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 33 * directories of an object of that type can be accessed by
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 34 * DIR *d = opendir("/example/directory") (or opendir("/example")
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 35 * to open the root of the filesystem), and then using readdir(d) etc.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 36 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 37 * The root directory is considered to contain all FileHandle and
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 38 * FileSystem objects, so the DIR* returned by opendir("/") will
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 39 * reflect this.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 40 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 41 * @note to create a directory, @see Dir
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 42 * @note Synchronization level: Set by subclass
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 43 * @ingroup platform
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 44 */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 45 class DirHandle : private NonCopyable<DirHandle> {
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 46 public:
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 47 virtual ~DirHandle() {}
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 48
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 49 /** Read the next directory entry
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 50 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 51 * @param ent The directory entry to fill out
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 52 * @return 1 on reading a filename, 0 at end of directory, negative error on failure
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 53 */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 54 virtual ssize_t read(struct dirent *ent) = 0;
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 55
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 56 /** Close a directory
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 57 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 58 * @return 0 on success, negative error code on failure
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 59 */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 60 virtual int close() = 0;
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 61
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 62 /** Set the current position of the directory
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 63 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 64 * @param offset Offset of the location to seek to,
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 65 * must be a value returned from tell
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 66 */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 67 virtual void seek(off_t offset) = 0;
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 68
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 69 /** Get the current position of the directory
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 70 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 71 * @return Position of the directory that can be passed to rewind
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 72 */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 73 virtual off_t tell() = 0;
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 74
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 75 /** Rewind the current position to the beginning of the directory
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 76 */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 77 virtual void rewind() = 0;
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 78
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 79 /** Get the sizeof the directory
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 80 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 81 * @return Number of files in the directory
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 82 */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 83 virtual size_t size()
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 84 {
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 85 off_t off = tell();
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 86 size_t size = 0;
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 87 struct dirent *ent = new struct dirent;
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 88
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 89 rewind();
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 90 while (read(ent) > 0) {
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 91 size += 1;
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 92 }
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 93 seek(off);
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 94
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 95 delete ent;
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 96 return size;
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 97 }
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 98
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 99 /** Closes the directory.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 100 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 101 * @returns
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 102 * 0 on success,
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 103 * -1 on error.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 104 */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 105 MBED_DEPRECATED_SINCE("mbed-os-5.4", "Replaced by DirHandle::close")
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 106 virtual int closedir() { return close(); };
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 107
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 108 /** Return the directory entry at the current position, and
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 109 * advances the position to the next entry.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 110 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 111 * @returns
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 112 * A pointer to a dirent structure representing the
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 113 * directory entry at the current position, or NULL on reaching
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 114 * end of directory or error.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 115 */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 116 MBED_DEPRECATED_SINCE("mbed-os-5.4", "Replaced by DirHandle::read")
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 117 virtual struct dirent *readdir()
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 118 {
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 119 static struct dirent ent;
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 120 return (read(&ent) > 0) ? &ent : NULL;
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 121 }
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 122
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 123 /** Resets the position to the beginning of the directory.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 124 */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 125 MBED_DEPRECATED_SINCE("mbed-os-5.4", "Replaced by DirHandle::rewind")
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 126 virtual void rewinddir() { rewind(); }
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 127
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 128 /** Returns the current position of the DirHandle.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 129 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 130 * @returns
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 131 * the current position,
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 132 * -1 on error.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 133 */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 134 MBED_DEPRECATED_SINCE("mbed-os-5.4", "Replaced by DirHandle::tell")
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 135 virtual off_t telldir() { return tell(); }
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 136
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 137 /** Sets the position of the DirHandle.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 138 *
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 139 * @param location The location to seek to. Must be a value returned by telldir.
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 140 */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 141 MBED_DEPRECATED_SINCE("mbed-os-5.4", "Replaced by DirHandle::seek")
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 142 virtual void seekdir(off_t location) { seek(location); }
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 143 };
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 144
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 145
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 146 } // namespace mbed
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 147
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 148 #endif /* MBED_DIRHANDLE_H */
abe5b02d-a2d4-4fe9-818e-c4e57c809ea4 0:bdf663c61a82 149