LibrePilot/flight/pios/posix/libraries/yaffs2/yaffs_osglue.c

/*
 * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
 *
 * Copyright (C) 2002-2011 Aleph One Ltd.
 *   for Toby Churchill Ltd and Brightstar Engineering
 *
 * Created by Charles Manning <charles@aleph1.co.uk>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

/*
 * Example OS glue functions for running on a Linux/POSIX system.
 */

#include "yaffscfg.h"
#include "yaffs_guts.h"
#include "yaffsfs.h"
#include "yaffs_trace.h"
#include <assert.h>

#include <errno.h>
#include <unistd.h>

#include "pios_trace.h"
#include "yaffsfs.h"

/*
 * yaffsfs_SetError() and yaffsfs_GetError()
 * Do whatever to set the system error.
 * yaffsfs_GetError() just fetches the last error.
 */

static int yaffsfs_lastError;

void yaffsfs_SetError(int err)
{
    // Do whatever to set error
    yaffsfs_lastError = err;
    errno = err;
    pios_trace(PIOS_TRACE_ERROR, "yaffsfs_SetError(%d) %s", err, yaffs_error_to_str(err));
}

int yaffsfs_GetLastError(void)
{
    return yaffsfs_lastError;
}

/*
 * yaffsfs_CheckMemRegion()
 * Check that access to an address is valid.
 * This can check memory is in bounds and is writable etc.
 *
 * Returns 0 if ok, negative if not.
 */
int yaffsfs_CheckMemRegion(const void *addr, size_t size, int write_request)
{
    if (!addr) {
        return -1;
    }
    return 0;
}

/*
 * yaffsfs_Lock()
 * yaffsfs_Unlock()
 * A single mechanism to lock and unlock yaffs. Hook up to a mutex or whatever.
 * Here are two examples, one using POSIX pthreads, the other doing nothing.
 *
 * If we use pthreads then we also start a background gc thread.
 */

#if 1

#include <pthread.h>

static pthread_mutex_t mutex1;
static pthread_t bc_gc_thread;

void yaffsfs_Lock(void)
{
    pthread_mutex_lock(&mutex1);
}

void yaffsfs_Unlock(void)
{
    pthread_mutex_unlock(&mutex1);
}

static void *bg_gc_func(void *dummy)
{
    struct yaffs_dev *dev;
    int urgent = 0;
    int result;
    int next_urgent;

    /* Sleep for a bit to allow start up */
    sleep(2);


    while (1) {
        /* Iterate through devices, do bg gc updating ungency */
        yaffs_dev_rewind();
        next_urgent = 0;

        while ((dev = yaffs_next_dev()) != NULL) {
            result = yaffs_do_background_gc_reldev(dev, urgent);
            if (result > 0) {
                next_urgent = 1;
            }
        }

        urgent = next_urgent;

        if (next_urgent) {
            sleep(1);
        } else {
            sleep(5);
        }
    }

    /* Don't ever return. */
    return NULL;
}

void yaffsfs_LockInit(void)
{
    /* Initialise lock */
    pthread_mutex_init(&mutex1, NULL);

    /* Sneak in starting a background gc thread too */
    // pthread_create(&bc_gc_thread, NULL, bg_gc_func, NULL);
}

#else /* if 1 */

void yaffsfs_Lock(void)
{}

void yaffsfs_Unlock(void)
{}

void yaffsfs_LockInit(void)
{}
#endif /* if 1 */

/*
 * yaffsfs_CurrentTime() retrns a 32-bit timestamp.
 *
 * Can return 0 if your system does not care about time.
 */

u32 yaffsfs_CurrentTime(void)
{
    return time(NULL);
}


/*
 * yaffsfs_malloc()
 * yaffsfs_free()
 *
 * Functions to allocate and free memory.
 */

#ifdef CONFIG_YAFFS_TEST_MALLOC

static int yaffs_kill_alloc  = 0;
static size_t total_malloced = 0;
static size_t malloc_limit   = 0 & 6000000;

void *yaffsfs_malloc(size_t size)
{
    void *this;

    if (yaffs_kill_alloc) {
        return NULL;
    }
    if (malloc_limit && malloc_limit < (total_malloced + size)) {
        return NULL;
    }

    this = malloc(size);
    if (this) {
        total_malloced += size;
    }
    return this;
}

#else /* ifdef CONFIG_YAFFS_TEST_MALLOC */

void *yaffsfs_malloc(size_t size)
{
    return malloc(size);
}

#endif /* ifdef CONFIG_YAFFS_TEST_MALLOC */

void yaffsfs_free(void *ptr)
{
    free(ptr);
}

void yaffsfs_OSInitialisation(void)
{
    yaffsfs_LockInit();
}

/*
 * yaffs_bug_fn()
 * Function to report a bug.
 */

void yaffs_bug_fn(const char *file_name, int line_no)
{
    printf("yaffs bug detected %s:%d\n",
           file_name, line_no);
    assert(0);
}