File content as of revision 1:62685faffa05:

/* 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_name++; // point to one char after the '/'
            break;
        }
        if (c == 0) { // end of object name, with no filename
            break;
        }
        len++;
        file_name++;
    }
    
    fs = FileSystemLike::lookup(file_system, len);
}

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

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

} // namespace mbed