mbed library sources

Dependents:   Encrypted my_mbed lklk CyaSSL_DTLS_Cellular ... more

Superseded

This library was superseded by mbed-dev - https://os.mbed.com/users/mbed_official/code/mbed-dev/.

Development branch of the mbed library sources. This library is kept in synch with the latest changes from the mbed SDK and it is not guaranteed to work.

If you are looking for a stable and tested release, please import one of the official mbed library releases:

Import librarymbed

The official Mbed 2 C/C++ SDK provides the software platform and libraries to build your applications.

cpp/FileSystemLike.cpp

Committer:
mbed_official
Date:
2012-11-20
Revision:
0:fd0d7bdfcdc2
Child:
1:62685faffa05

File content as of revision 0:fd0d7bdfcdc2:

/* mbed Microcontroller Library
 * Copyright (c) 2006-2012 ARM Limited
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
#include "FileSystemLike.h"

namespace mbed {

FileSystemLike::FileSystemLike(const char *name) {
    _name = name;
    
    if (name != NULL) {
        // put this object at head of the list
        _next = _head;
        _head = this;
    } else {
        _next = NULL;
    }
}

FileSystemLike::~FileSystemLike() {
    if (_name != NULL) {
        // remove this object from the list
        if (_head == this) { // first in the list, so just drop me
            _head = _next;
        } else {             // find the object before me, then drop me
            FileSystemLike* p = _head;
            while (p->_next != this) {
                p = p->_next;
            }
            p->_next = _next;
        }
    }
}

FileSystemLike *FileSystemLike::lookup(const char *name, unsigned int len) {
    FileSystemLike *p = _head;
    while (p != NULL) {
        /* Check that p->_name matches name and is the correct length */
        if (p->_name != NULL && std::strncmp(p->_name, name, len) == 0 && std::strlen(p->_name) == len) {
            return p;
        }
        p = p->_next;
    }
    return NULL;
}

class BaseDirHandle : public DirHandle {
public:
    /*
      We keep track of our current location as the n'th object in the
      FileSystemLike list. Using a Base* instead would cause problems if that
      object were to be destroyed between readdirs.
      Using this method does mean though that destroying/creating objects can
      give unusual results from readdir.
    */
    off_t n;
    struct dirent cur_entry;
    
    BaseDirHandle() {
        n = 0;
    }
    
    virtual int closedir() {
        delete this;
        return 0;
    }
    
    virtual struct dirent *readdir() {
        FileSystemLike *ptr = FileSystemLike::_head;
        /* Find the n'th FileLike or FileSystemLike object in the Base list */
        int m = 0;
        while (1) {
            if (ptr == NULL) {
                /* No such object */
                return NULL;
            }
            if (m == n) break;
            
            m++;
            ptr = ptr->_next;
        }
        /* Increment n, so next readdir gets the next item */
        n++;
        /* Setup curentry and return a pointer to it */
        std::strncpy(cur_entry.d_name, ptr->_name, NAME_MAX);
        return &cur_entry;
    }
    
    virtual off_t telldir() {
        return n;
    }
    
    virtual void seekdir(off_t offset) { 
        n = offset;
    }
    
    virtual void rewinddir() {
        n = 0;
    }
};

DirHandle *FileSystemLike::opendir() {
    return new BaseDirHandle();
}

FileSystemLike *FileSystemLike::_head = NULL;


FilePath::FilePath(const char* file_path) : file_name(NULL), fs(NULL) {
    if ((file_path[0] != '/') || (file_path[1] == 0)) return;
    
    const char* file_system = &file_path[1];
    file_name = file_system;
    int len = 0;
    while (true) {
        char c = *file_name++;
        if (c == '/') { // end of object name
            /* file now points to one char after the '/' */
            break;
        }
        if (c == 0) { // end of object name, with no filename
            file_name = NULL;
            break;
        }
        len++;
    }
    
    fs = FileSystemLike::lookup(file_system, len);
}

const char* FilePath::fileName(void) {
    return file_name;
}

FileSystemLike* FilePath::fileSystem(void) {
    return fs;
}

FileSystemLike* FilePath::getFileSystem(const char* path) {
    FilePath f(path);
    return f.fs;
}

} // namespace mbed