release/src-rt-6.x.4708/cfe/cfe/include/env_subr.h

   1 /*  *********************************************************************
   2     *  Broadcom Common Firmware Environment (CFE)
   3     *
   4     *  Environment helper routines              File: env_subr.h
   5     *
   6     *  Definitions and prototypes for environment variable subroutines
   7     *
   8     *  Author:  Mitch Lichtenberg (mpl@broadcom.com)
   9     *
  10     *********************************************************************
  11     *
  12     *  Copyright 2000,2001,2002,2003
  13     *  Broadcom Corporation. All rights reserved.
  14     *
  15     *  This software is furnished under license and may be used and
  16     *  copied only in accordance with the following terms and
  17     *  conditions.  Subject to these conditions, you may download,
  18     *  copy, install, use, modify and distribute modified or unmodified
  19     *  copies of this software in source and/or binary form.  No title
  20     *  or ownership is transferred hereby.
  21     *
  22     *  1) Any source code used, modified or distributed must reproduce
  23     *     and retain this copyright notice and list of conditions
  24     *     as they appear in the source file.
  25     *
  26     *  2) No right is granted to use any trade name, trademark, or
  27     *     logo of Broadcom Corporation.  The "Broadcom Corporation"
  28     *     name may not be used to endorse or promote products derived
  29     *     from this software without the prior written permission of
  30     *     Broadcom Corporation.
  31     *
  32     *  3) THIS SOFTWARE IS PROVIDED "AS-IS" AND ANY EXPRESS OR
  33     *     IMPLIED WARRANTIES, INCLUDING BUT NOT LIMITED TO, ANY IMPLIED
  34     *     WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
  35     *     PURPOSE, OR NON-INFRINGEMENT ARE DISCLAIMED. IN NO EVENT
  36     *     SHALL BROADCOM BE LIABLE FOR ANY DAMAGES WHATSOEVER, AND IN
  37     *     PARTICULAR, BROADCOM SHALL NOT BE LIABLE FOR DIRECT, INDIRECT,
  38     *     INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  39     *     (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  40     *     GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  41     *     BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  42     *     OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
  43     *     TORT (INCLUDING NEGLIGENCE OR OTHERWISE), EVEN IF ADVISED OF
  44     *     THE POSSIBILITY OF SUCH DAMAGE.
  45     ********************************************************************* */
  46
  47
  48
  49 /*  *********************************************************************
  50     *  Constants
  51     ********************************************************************* */
  52
  53
  54 /*
  55  * TLV types.  These codes are used in the "type-length-value"
  56  * encoding of the items stored in the NVRAM device (flash or EEPROM)
  57  *
  58  * The layout of the flash/nvram is as follows:
  59  *
  60  * <type> <length> <data ...> <type> <length> <data ...> <type_end>
  61  *
  62  * The type code of "ENV_TLV_TYPE_END" marks the end of the list.
  63  * The "length" field marks the length of the data section, not
  64  * including the type and length fields.
  65  *
  66  * Environment variables are stored as follows:
  67  *
  68  * <type_env> <length> <flags> <name> = <value>
  69  *
  70  * If bit 0 (low bit) is set, the length is an 8-bit value.
  71  * If bit 0 (low bit) is clear, the length is a 16-bit value
  72  *
  73  * Bit 7 set indicates "user" TLVs.  In this case, bit 0 still
  74  * indicates the size of the length field.
  75  *
  76  * Flags are from the constants below:
  77  *
  78  */
  79
  80 #define ENV_LENGTH_16BITS       0x00    /* for low bit */
  81 #define ENV_LENGTH_8BITS        0x01
  82
  83 #define ENV_TYPE_USER           0x80
  84
  85 #define ENV_CODE_SYS(n,l) (((n)<<1)|(l))
  86 #define ENV_CODE_USER(n,l) ((((n)<<1)|(l)) | ENV_TYPE_USER)
  87
  88 /*
  89  * The actual TLV types we support
  90  */
  91
  92 #define ENV_TLV_TYPE_END        0x00
  93 #define ENV_TLV_TYPE_ENV        ENV_CODE_SYS(0,ENV_LENGTH_8BITS)
  94
  95 /*
  96  * Environment variable flags
  97  */
  98
  99 #define ENV_FLG_NORMAL          0x00    /* normal read/write */
 100 #define ENV_FLG_BUILTIN         0x01    /* builtin - not stored in flash */
 101 #define ENV_FLG_READONLY        0x02    /* read-only - cannot be changed */
 102
 103 #define ENV_FLG_MASK            0xFF    /* mask of attributes we keep */
 104 #define ENV_FLG_ADMIN           0x100   /* lets us internally override permissions */
 105
 106 /*  *********************************************************************
 107     *  Prototypes
 108     ********************************************************************* */
 109
 110 int env_delenv(const char *name);
 111 char *env_getenv(const char *name);
 112 int env_setenv(const char *name,char *value,int flags);
 113 int env_load(void);
 114 int env_save(void);
 115 int env_enum(int idx,char *name,int *namelen,char *val,int *vallen);
 116 int env_envtype(const char *name);