xref: /openbmc/u-boot/tools/env/fw_env.h (revision dd1033e4)
1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * (C) Copyright 2002-2008
4  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5  */
6 
7 #include <stdint.h>
8 
9 /*
10  * Programs using the library must check which API is available,
11  * that varies depending on the U-Boot version.
12  * This can be changed in future
13  */
14 #define FW_ENV_API_VERSION	1
15 
16 struct env_opts {
17 #ifdef CONFIG_FILE
18 	char *config_file;
19 #endif
20 	char *lockname;
21 };
22 
23 /**
24  * fw_printenv() - print one or several environment variables
25  *
26  * @argc: number of variables names to be printed, prints all if 0
27  * @argv: array of variable names to be printed, if argc != 0
28  * @value_only: do not repeat the variable name, print the bare value,
29  *          only one variable allowed with this option, argc must be 1
30  * @opts: encryption key, configuration file, defaults are used if NULL
31  *
32  * Description:
33  *  Uses fw_env_open, fw_getenv
34  *
35  * Return:
36  *  0 on success, -1 on failure (modifies errno)
37  */
38 int fw_printenv(int argc, char *argv[], int value_only, struct env_opts *opts);
39 
40 /**
41  * fw_env_set() - adds or removes one variable to the environment
42  *
43  * @argc: number of strings in argv, argv[0] is variable name,
44  *          argc==1 means erase variable, argc > 1 means add a variable
45  * @argv: argv[0] is variable name, argv[1..argc-1] are concatenated separated
46  *           by single blank and set as the new value of the variable
47  * @opts: how to retrieve environment from flash, defaults are used if NULL
48  *
49  * Description:
50  *  Uses fw_env_open, fw_env_write, fw_env_flush
51  *
52  * Return:
53  *  0 on success, -1 on failure (modifies errno)
54  *
55  * ERRORS:
56  *  EROFS - some variables ("ethaddr", "serial#") cannot be modified
57  */
58 int fw_env_set(int argc, char *argv[], struct env_opts *opts);
59 
60 /**
61  * fw_parse_script() - adds or removes multiple variables with a batch script
62  *
63  * @fname: batch script file name
64  * @opts: encryption key, configuration file, defaults are used if NULL
65  *
66  * Description:
67  *  Uses fw_env_open, fw_env_write, fw_env_flush
68  *
69  * Return:
70  *  0 success, -1 on failure (modifies errno)
71  *
72  * Script Syntax:
73  *
74  *  key [ [space]+ value]
75  *
76  *  lines starting with '#' treated as comment
77  *
78  *  A variable without value will be deleted. Any number of spaces are allowed
79  *  between key and value. The value starts with the first non-space character
80  *  and ends with newline. No comments allowed on these lines.  Spaces inside
81  *  the value are preserved verbatim.
82  *
83  * Script Example:
84  *
85  *  netdev         eth0
86  *
87  *  kernel_addr    400000
88  *
89  *  foo            spaces           are copied verbatim
90  *
91  *  # delete variable bar
92  *
93  *  bar
94  */
95 int fw_parse_script(char *fname, struct env_opts *opts);
96 
97 
98 /**
99  * fw_env_open() - read enviroment from flash into RAM cache
100  *
101  * @opts: encryption key, configuration file, defaults are used if NULL
102  *
103  * Return:
104  *  0 on success, -1 on failure (modifies errno)
105  */
106 int fw_env_open(struct env_opts *opts);
107 
108 /**
109  * fw_getenv() - lookup variable in the RAM cache
110  *
111  * @name: variable to be searched
112  * Return:
113  *  pointer to start of value, NULL if not found
114  */
115 char *fw_getenv(char *name);
116 
117 /**
118  * fw_env_write() - modify a variable held in the RAM cache
119  *
120  * @name: variable
121  * @value: delete variable if NULL, otherwise create or overwrite the variable
122  *
123  * This is called in sequence to update the environment in RAM without updating
124  * the copy in flash after each set
125  *
126  * Return:
127  *  0 on success, -1 on failure (modifies errno)
128  *
129  * ERRORS:
130  *  EROFS - some variables ("ethaddr", "serial#") cannot be modified
131  */
132 int fw_env_write(char *name, char *value);
133 
134 /**
135  * fw_env_flush - write the environment from RAM cache back to flash
136  *
137  * @opts: encryption key, configuration file, defaults are used if NULL
138  *
139  * Return:
140  *  0 on success, -1 on failure (modifies errno)
141  */
142 int fw_env_flush(struct env_opts *opts);
143 
144 /**
145  * fw_env_close - free allocated structure and close env
146  *
147  * @opts: encryption key, configuration file, defaults are used if NULL
148  *
149  * Return:
150  *  0 on success, -1 on failure (modifies errno)
151  */
152 int fw_env_close(struct env_opts *opts);
153 
154 
155 /**
156  * fw_env_version - return the current version of the library
157  *
158  * Return:
159  *  version string of the library
160  */
161 char *fw_env_version(void);
162 
163 unsigned long crc32(unsigned long, const unsigned char *, unsigned);
164