xref: /openbmc/u-boot/tools/env/fw_env.h (revision cd1cc31f)
1 /*
2  * (C) Copyright 2002-2008
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <stdint.h>
9 
10 /*
11  * Programs using the library must check which API is available,
12  * that varies depending on the U-Boot version.
13  * This can be changed in future
14  */
15 #define FW_ENV_API_VERSION	1
16 
17 struct env_opts {
18 #ifdef CONFIG_FILE
19 	char *config_file;
20 #endif
21 	char *lockname;
22 };
23 
24 /**
25  * fw_printenv() - print one or several environment variables
26  *
27  * @argc: number of variables names to be printed, prints all if 0
28  * @argv: array of variable names to be printed, if argc != 0
29  * @value_only: do not repeat the variable name, print the bare value,
30  *          only one variable allowed with this option, argc must be 1
31  * @opts: encryption key, configuration file, defaults are used if NULL
32  *
33  * Description:
34  *  Uses fw_env_open, fw_getenv
35  *
36  * Return:
37  *  0 on success, -1 on failure (modifies errno)
38  */
39 int fw_printenv(int argc, char *argv[], int value_only, struct env_opts *opts);
40 
41 /**
42  * fw_env_set() - adds or removes one variable to the environment
43  *
44  * @argc: number of strings in argv, argv[0] is variable name,
45  *          argc==1 means erase variable, argc > 1 means add a variable
46  * @argv: argv[0] is variable name, argv[1..argc-1] are concatenated separated
47  *           by single blank and set as the new value of the variable
48  * @opts: how to retrieve environment from flash, defaults are used if NULL
49  *
50  * Description:
51  *  Uses fw_env_open, fw_env_write, fw_env_flush
52  *
53  * Return:
54  *  0 on success, -1 on failure (modifies errno)
55  *
56  * ERRORS:
57  *  EROFS - some variables ("ethaddr", "serial#") cannot be modified
58  */
59 int fw_env_set(int argc, char *argv[], struct env_opts *opts);
60 
61 /**
62  * fw_parse_script() - adds or removes multiple variables with a batch script
63  *
64  * @fname: batch script file name
65  * @opts: encryption key, configuration file, defaults are used if NULL
66  *
67  * Description:
68  *  Uses fw_env_open, fw_env_write, fw_env_flush
69  *
70  * Return:
71  *  0 success, -1 on failure (modifies errno)
72  *
73  * Script Syntax:
74  *
75  *  key [ [space]+ value]
76  *
77  *  lines starting with '#' treated as comment
78  *
79  *  A variable without value will be deleted. Any number of spaces are allowed
80  *  between key and value. The value starts with the first non-space character
81  *  and ends with newline. No comments allowed on these lines.  Spaces inside
82  *  the value are preserved verbatim.
83  *
84  * Script Example:
85  *
86  *  netdev         eth0
87  *
88  *  kernel_addr    400000
89  *
90  *  foo            spaces           are copied verbatim
91  *
92  *  # delete variable bar
93  *
94  *  bar
95  */
96 int fw_parse_script(char *fname, struct env_opts *opts);
97 
98 
99 /**
100  * fw_env_open() - read enviroment from flash into RAM cache
101  *
102  * @opts: encryption key, configuration file, defaults are used if NULL
103  *
104  * Return:
105  *  0 on success, -1 on failure (modifies errno)
106  */
107 int fw_env_open(struct env_opts *opts);
108 
109 /**
110  * fw_getenv() - lookup variable in the RAM cache
111  *
112  * @name: variable to be searched
113  * Return:
114  *  pointer to start of value, NULL if not found
115  */
116 char *fw_getenv(char *name);
117 
118 /**
119  * fw_env_write() - modify a variable held in the RAM cache
120  *
121  * @name: variable
122  * @value: delete variable if NULL, otherwise create or overwrite the variable
123  *
124  * This is called in sequence to update the environment in RAM without updating
125  * the copy in flash after each set
126  *
127  * Return:
128  *  0 on success, -1 on failure (modifies errno)
129  *
130  * ERRORS:
131  *  EROFS - some variables ("ethaddr", "serial#") cannot be modified
132  */
133 int fw_env_write(char *name, char *value);
134 
135 /**
136  * fw_env_flush - write the environment from RAM cache back to flash
137  *
138  * @opts: encryption key, configuration file, defaults are used if NULL
139  *
140  * Return:
141  *  0 on success, -1 on failure (modifies errno)
142  */
143 int fw_env_flush(struct env_opts *opts);
144 
145 /**
146  * fw_env_close - free allocated structure and close env
147  *
148  * @opts: encryption key, configuration file, defaults are used if NULL
149  *
150  * Return:
151  *  0 on success, -1 on failure (modifies errno)
152  */
153 int fw_env_close(struct env_opts *opts);
154 
155 
156 /**
157  * fw_env_version - return the current version of the library
158  *
159  * Return:
160  *  version string of the library
161  */
162 char *fw_env_version(void);
163 
164 unsigned long crc32(unsigned long, const unsigned char *, unsigned);
165