[package] rename unvram to nvram
[openwrt/svn-archive/archive.git] / package / nvram / src / nvram.h
1 /*
2 * NVRAM variable manipulation
3 *
4 * Copyright 2007, Broadcom Corporation
5 * Copyright 2009, OpenWrt.org
6 * All Rights Reserved.
7 *
8 * THIS SOFTWARE IS OFFERED "AS IS", AND BROADCOM GRANTS NO WARRANTIES OF ANY
9 * KIND, EXPRESS OR IMPLIED, BY STATUTE, COMMUNICATION OR OTHERWISE. BROADCOM
10 * SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
11 * FOR A SPECIFIC PURPOSE OR NONINFRINGEMENT CONCERNING THIS SOFTWARE.
12 *
13 */
14
15 #ifndef _nvram_h_
16 #define _nvram_h_
17
18 #include <stdint.h>
19 #include <string.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <fcntl.h>
23 #include <unistd.h>
24 #include <errno.h>
25 #include <sys/mman.h>
26 #include <sys/stat.h>
27 #include <linux/limits.h>
28
29 #include "sdinitvals.h"
30
31
32 struct nvram_header {
33 uint32_t magic;
34 uint32_t len;
35 uint32_t crc_ver_init; /* 0:7 crc, 8:15 ver, 16:31 sdram_init */
36 uint32_t config_refresh; /* 0:15 sdram_config, 16:31 sdram_refresh */
37 uint32_t config_ncdl; /* ncdl values for memc */
38 } __attribute__((__packed__));
39
40 struct nvram_tuple {
41 char *name;
42 char *value;
43 struct nvram_tuple *next;
44 };
45
46 struct nvram_handle {
47 int fd;
48 char *mmap;
49 unsigned long length;
50 struct nvram_tuple *nvram_hash[257];
51 struct nvram_tuple *nvram_dead;
52 };
53
54 typedef struct nvram_handle nvram_handle_t;
55 typedef struct nvram_header nvram_header_t;
56 typedef struct nvram_tuple nvram_tuple_t;
57
58
59 /* Get nvram header. */
60 nvram_header_t * nvram_header(nvram_handle_t *h);
61
62 /* Set the value of an NVRAM variable */
63 int nvram_set(nvram_handle_t *h, const char *name, const char *value);
64
65 /* Get the value of an NVRAM variable. */
66 char * nvram_get(nvram_handle_t *h, const char *name);
67
68 /* Unset the value of an NVRAM variable. */
69 int nvram_unset(nvram_handle_t *h, const char *name);
70
71 /* Get all NVRAM variables. */
72 nvram_tuple_t * nvram_getall(nvram_handle_t *h);
73
74 /* Regenerate NVRAM. */
75 int nvram_commit(nvram_handle_t *h);
76
77 /* Open NVRAM and obtain a handle. */
78 nvram_handle_t * nvram_open(const char *file, int rdonly);
79
80 /* Close NVRAM and free memory. */
81 int nvram_close(nvram_handle_t *h);
82
83 /* Get the value of an NVRAM variable in a safe way, use "" instead of NULL. */
84 #define nvram_safe_get(h, name) (nvram_get(h, name) ? : "")
85
86 /* Computes a crc8 over the input data. */
87 uint8_t hndcrc8 (uint8_t * pdata, uint32_t nbytes, uint8_t crc);
88
89 /* Returns the crc value of the nvram. */
90 uint8_t nvram_calc_crc(nvram_header_t * nvh);
91
92 /* Determine NVRAM device node. */
93 char * nvram_find_mtd(void);
94
95 /* Copy NVRAM contents to staging file. */
96 int nvram_to_staging(void);
97
98 /* Copy staging file to NVRAM device. */
99 int staging_to_nvram(void);
100
101 /* Check NVRAM staging file. */
102 char * nvram_find_staging(void);
103
104
105 /* Staging file for NVRAM */
106 #define NVRAM_STAGING "/tmp/.nvram"
107 #define NVRAM_RO 1
108 #define NVRAM_RW 0
109
110 /* Helper macros */
111 #define NVRAM_ARRAYSIZE(a) sizeof(a)/sizeof(a[0])
112 #define NVRAM_ROUNDUP(x, y) ((((x)+((y)-1))/(y))*(y))
113
114 /* NVRAM constants */
115 #define NVRAM_SPACE 0x8000
116 #define NVRAM_START(x) x - NVRAM_SPACE
117 #define NVRAM_MAGIC 0x48534C46 /* 'FLSH' */
118 #define NVRAM_VERSION 1
119
120 #define NVRAM_CRC_START_POSITION 9 /* magic, len, crc8 to be skipped */
121
122
123 #endif /* _nvram_h_ */