source: src/router/nvram/nvram_linux.c @ 17874

/*
 * NVRAM variable manipulation (Linux user mode half)
 *
 * Copyright 2001-2003, Broadcom Corporation
 * All Rights Reserved.
 *
 * THIS SOFTWARE IS OFFERED "AS IS", AND BROADCOM GRANTS NO WARRANTIES OF ANY
 * KIND, EXPRESS OR IMPLIED, BY STATUTE, COMMUNICATION OR OTHERWISE. BROADCOM
 * SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A SPECIFIC PURPOSE OR NONINFRINGEMENT CONCERNING THIS SOFTWARE.
 *
 * $Id: nvram_linux.c,v 1.9 2003/12/03 10:14:06 honor Exp $
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <error.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/mman.h>

#include <typedefs.h>
#include <bcmnvram.h>
#include <nvram_convert.h>

#define PATH_DEV_NVRAM "/dev/nvram"

/* Globals */
static int nvram_fd = -1;
static char *nvram_buf = NULL;

int nvram_init(void *unused)
{
#ifdef HAVE_X86
        FILE *in = fopen("/usr/local/nvram/nvram.bin", "rb");
        if (in==NULL)
            return -1;
        fclose(in);
#endif
        if ((nvram_fd = open(PATH_DEV_NVRAM, O_RDWR)) < 0)
                goto err;

        /* Map kernel string buffer into user space */
        if ((nvram_buf =
             mmap(NULL, NVRAM_SPACE, PROT_READ, MAP_SHARED, nvram_fd,
                  0)) == MAP_FAILED) {
                close(nvram_fd);
                fprintf(stderr, "nvram_init(): failed\n");
                nvram_fd = -1;
                goto err;
        }

        return 0;

err:
        return errno;
}

void lock(void)
{
        FILE *in;
        int lockwait = 0;
        while ((in = fopen("/tmp/.nvlock", "rb")) != NULL) {
                fclose(in);
                fprintf(stderr, "nvram lock, waiting....\n");
                lockwait++;
                if (lockwait == 3)
                        unlink("/tmp/.nvlock"); //something crashed, we fix it
                sleep(1);
        }
        in = fopen("/tmp/.nvlock", "wb");
        fprintf(in, "lock");
        fclose(in);
}

void unlock(void)
{
        unlink("/tmp/.nvlock");
}

char *nvram_get(const char *name)
{
//lock();
        size_t count = strlen(name) + 1;
        char tmp[100], *value;
        unsigned long *off = (unsigned long *)tmp;

        if (nvram_fd < 0)
                if (nvram_init(NULL)) {
                        //unlock();
                        return NULL;
                }
        if (count > sizeof(tmp)) {
                if (!(off = malloc(count))) {
                        //unlock();
                        return NULL;
                }
        }

        /* Get offset into mmap() space */
        strcpy((char *)off, name);

        count = read(nvram_fd, off, count);

        if (count == sizeof(unsigned long))
                value = &nvram_buf[*off];
        else
                value = NULL;
        
#ifndef HAVE_MICRO
        if (value)
            msync(nvram_buf, NVRAM_SPACE, MS_INVALIDATE);
#endif
        if (count < 0)
                perror(PATH_DEV_NVRAM);

        if (off != (unsigned long *)tmp)
                free(off);
        //unlock();


        return value;
}

int nvram_getall(char *buf, int count)
{
//lock();
        int ret;

        if (nvram_fd < 0)
                if ((ret = nvram_init(NULL))) {
                        //unlock();
                        return ret;
                }
        if (count == 0) {
                //unlock();
                return 0;
        }
        /* Get all variables */
        *buf = '\0';

        ret = read(nvram_fd, buf, count);

        if (ret < 0)
                perror(PATH_DEV_NVRAM);
        //unlock();
        return (ret == count) ? 0 : ret;
}

void nvram_open(void)           // dummy
{
}

void nvram_close(void)          //dummy
{
}

static int _nvram_set(const char *name, const char *value)
{
        size_t count = strlen(name) + 1;
        char tmp[100], *buf = tmp;
        int ret;

        if (nvram_fd < 0)
                if ((ret = nvram_init(NULL)))
                        return ret;

        /* Wolf add - keep nvram varname to sane len - may prevent corruption */
        if (strlen(name) > 64)
                return -ENOMEM;

        /* Unset if value is NULL */
        if (value)
                count += strlen(value) + 2;

        if (count > sizeof(tmp)) {
                if (!(buf = malloc(count)))
                        return -ENOMEM;
        }

        if (value)
                sprintf(buf, "%s=%s", name, value);
        else
                strcpy(buf, name);

        ret = write(nvram_fd, buf, count);

        if (ret < 0)
                perror(PATH_DEV_NVRAM);

        if (buf != tmp)
                free(buf);

        return (ret == count) ? 0 : ret;
}

int nvram_set(const char *name, const char *value)
{
        extern struct nvram_convert nvram_converts[];
        struct nvram_convert *v;
        int ret;
#ifdef HAVE_NOWIFI
        if (!strcmp(name, "ip_conntrack_max") && value != NULL) {
                int val = atoi(value);
                if (val > 4096) {
                        return _nvram_set(name, "4096");
                }

        }
#endif
        ret = _nvram_set(name, value);

        for (v = nvram_converts; v->name; v++) {
                if (!strcmp(v->name, name)) {
                        if (strcmp(v->wl0_name, ""))
                                _nvram_set(v->wl0_name, value);
                }
        }
        return ret;
}

int nvram_immed_set(const char *name, const char *value)
{
        return nvram_set(name, value);
}

int nvram_unset(const char *name)
{
//lock();
        int v = _nvram_set(name, NULL);
//unlock();
        return v;
}

int nvram_commit(void)
{
        if (nvram_match("flash_active", "1")) {
                fprintf(stderr, "not allowed, flash process in progress");
                exit(1);
        }
#if defined(HAVE_WZRHPG300NH) || defined(HAVE_WHRHPGN) || defined(HAVE_WZRHPAG300NH) || defined(HAVE_DIR825) || defined(HAVE_TEW632BRP) || defined(HAVE_TG2521) || defined(HAVE_WR1043)  || defined(HAVE_WRT400) || defined(HAVE_WZRHPAG300NH) || defined(HAVE_WZRG450) || defined(HAVE_DANUBE) 
        system("/sbin/ledtool 1"); 
#elif HAVE_LSX
        //nothing
#else
        system("/sbin/ledtool 1");
#endif
        lock();
        int ret;
        if (nvram_fd < 0) {
                if ((ret = nvram_init(NULL))) {
                        fprintf(stderr, "nvram_commit(): failed\n");
                        unlock();
                        return ret;
                }
        }
        ret = ioctl(nvram_fd, NVRAM_MAGIC, NULL);

        if (ret < 0) {
                fprintf(stderr, "nvram_commit(): failed\n");
                perror(PATH_DEV_NVRAM);
        }
        unlock();
        sync();
        return ret;
}

int file2nvram(char *filename, char *varname)
{
        FILE *fp;
        int c, count;
        int i = 0, j = 0;
        char mem[10000], buf[30000];

        if (!(fp = fopen(filename, "rb")))
                return 0;

        count = fread(mem, 1, sizeof(mem), fp);
        fclose(fp);
        for (j = 0; j < count; j++) {
                if (i > sizeof(buf) - 3)
                        break;
                c = mem[j];
                if (c >= 32 && c <= 126 && c != '~') {
                        buf[i++] = (unsigned char)c;
                } else if (c == 13) {
                        buf[i++] = (unsigned char)c;
                } else if (c == 0) {
                        buf[i++] = '~';
                } else if (c == 10) {
                        buf[i++] = (unsigned char)c;
                } else {
                        buf[i++] = '\\';
                        sprintf(buf + i, "%02X", c);
                        i += 2;
                }
        }
        if (i == 0)
                return 0;
        buf[i] = 0;
        //fprintf(stderr,"================ > file2nvram %s = [%s] \n",varname,buf); 
        nvram_set(varname, buf);
        return 0;

}

int nvram2file(char *varname, char *filename)
{
        FILE *fp;
        int c, tmp;
        int i = 0, j = 0;
        char *buf;
        char mem[10000];

        if (!(fp = fopen(filename, "wb")))
                return 0;

        buf = strdup(nvram_safe_get(varname));
        //fprintf(stderr,"=================> nvram2file %s = [%s] \n",varname,buf);
        while (buf[i] && j < sizeof(mem) - 3) {
/*        if (buf[i] == '\\')  {
                i++;
                tmp=buf[i+2];
                buf[i+2]=0;
                sscanf(buf+i,"%02X",&c);
                buf[i+2]=tmp;
                i+=2;
                mem[j]=c;j++;
        } else */
                if (buf[i] == '~') {
                        mem[j] = 0;
                        j++;
                        i++;
                } else {
                        mem[j] = buf[i];
                        j++;
                        i++;
                }
        }
        if (j <= 0)
                return j;
        j = fwrite(mem, 1, j, fp);
        fclose(fp);
        free(buf);
        return j;
}

#include "nvram_generics.h"