1 /* SPDX-License-Identifier: GPL-2.0+ */
3 * Common environment functions
5 * (C) Copyright 2000-2009
6 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
13 #include <linux/types.h>
16 * env_get_id() - Gets a sequence number for the environment
18 * This value increments every time the environment changes, so can be used an
19 * an indication of this
21 * @return environment ID
26 * env_init() - Set up the pre-relocation environment
28 * This locates the environment or uses the default if nothing is available.
29 * This must be called before env_get() will work.
31 * @return 0 if OK, -ENODEV if no environment drivers are enabled
36 * env_relocate() - Set up the post-relocation environment
38 * This loads the environment into RAM so that it can be modified. This is
39 * called after relocation, before the environment is used
41 void env_relocate(void);
44 * env_match() - Match a name / name=value pair
46 * This is used prior to relocation for finding envrionment variables
48 * @name: A simple 'name', or a 'name=value' pair.
49 * @index: The environment index for a 'name2=value2' pair.
50 * @return index for the value if the names match, else -1.
52 int env_match(unsigned char *name, int index);
55 * env_get_f() - Look up the value of an environment variable (early)
57 * This function is called from env_get() if the environment has not been
58 * loaded yet (GD_FLG_ENV_READY flag is 0). Some environment locations will
59 * support reading the value (slowly) and some will not.
61 * @varname: Variable to look up
62 * @return value of variable, or NULL if not found
64 int env_get_f(const char *name, char *buf, unsigned int len);
67 * env_get_yesno() - Read an environment variable as a boolean
69 * @return 1 if yes/true (Y/y/T/t), -1 if variable does not exist (i.e. default
70 * to true), 0 if otherwise
72 int env_get_yesno(const char *var);
75 * env_set() - set an environment variable
77 * This sets or deletes the value of an environment variable. For setting the
78 * value the variable is created if it does not already exist.
80 * @varname: Variable to adjust
81 * @value: Value to set for the variable, or NULL or "" to delete the variable
82 * @return 0 if OK, 1 on error
84 int env_set(const char *varname, const char *value);
87 * env_get_ulong() - Return an environment variable as an integer value
89 * Most U-Boot environment variables store hex values. For those which store
90 * (e.g.) base-10 integers, this function can be used to read the value.
92 * @name: Variable to look up
93 * @base: Base to use (e.g. 10 for base 10, 2 for binary)
94 * @default_val: Default value to return if no value is found
95 * @return the value found, or @default_val if none
97 ulong env_get_ulong(const char *name, int base, ulong default_val);
100 * env_set_ulong() - set an environment variable to an integer
102 * @varname: Variable to adjust
103 * @value: Value to set for the variable (will be converted to a string)
104 * @return 0 if OK, 1 on error
106 int env_set_ulong(const char *varname, ulong value);
109 * env_get_hex() - Return an environment variable as a hex value
111 * Decode an environment as a hex number (it may or may not have a 0x
112 * prefix). If the environment variable cannot be found, or does not start
113 * with hex digits, the default value is returned.
115 * @varname: Variable to decode
116 * @default_val: Value to return on error
118 ulong env_get_hex(const char *varname, ulong default_val);
121 * env_set_hex() - set an environment variable to a hex value
123 * @varname: Variable to adjust
124 * @value: Value to set for the variable (will be converted to a hex string)
125 * @return 0 if OK, 1 on error
127 int env_set_hex(const char *varname, ulong value);
130 * env_set_addr - Set an environment variable to an address in hex
132 * @varname: Environment variable to set
133 * @addr: Value to set it to
134 * @return 0 if ok, 1 on error
136 static inline int env_set_addr(const char *varname, const void *addr)
138 return env_set_hex(varname, (ulong)addr);
142 * env_complete() - return an auto-complete for environment variables
144 * @var: partial name to auto-complete
145 * @maxv: Maximum number of matches to return
146 * @cmdv: Returns a list of possible matches
147 * @maxsz: Size of buffer to use for matches
148 * @buf: Buffer to use for matches
149 * @dollar_comp: non-zero to wrap each match in ${...}
150 * @return number of matches found (in @cmdv)
152 int env_complete(char *var, int maxv, char *cmdv[], int maxsz, char *buf,