illumos: manual page: nvlist_lookup

NVLIST_LOOKUP_BOOLEAN(9F) Kernel Functions for Drivers

NAME

nvlist_lookup_boolean, nvlist_lookup_boolean_value, nvlist_lookup_byte,
nvlist_lookup_int8, nvlist_lookup_int16, nvlist_lookup_int32,
nvlist_lookup_int64, nvlist_lookup_uint8, nvlist_lookup_uint16,
nvlist_lookup_uint32, nvlist_lookup_uint64, nvlist_lookup_string,
nvlist_lookup_nvlist, nvlist_lookup_boolean_array,
nvlist_lookup_byte_array, nvlist_lookup_int8_array,
nvlist_lookup_int16_array, nvlist_lookup_int32_array,
nvlist_lookup_int64_array, nvlist_lookup_uint8_array,
nvlist_lookup_uint16_array, nvlist_lookup_uint32_array,
nvlist_lookup_uint64_array, nvlist_lookup_string_array,
nvlist_lookup_nvlist_array, nvlist_lookup_pairs - match name and type
indicated by the interface name and retrieve data value

SYNOPSIS

#include <sys/nvpair.h>

int nvlist_lookup_boolean(nvlist_t *nvl, const char *name);

int nvlist_lookup_boolean_value(nvlist_t *nvl, const char *name,
boolean_t *val);

int nvlist_lookup_byte(nvlist_t *nvl, const char *name,
uchar_t *val);

int nvlist_lookup_int8(nvlist_t *nvl, const char *name,
int8_t *val);

int nvlist_lookup_uint8(nvlist_t *nvl, const char *name,
uint8_t *val);

int nvlist_lookup_int16(nvlist_t *nvl, const char *name,
int16_t *val);

int nvlist_lookup_uint16(nvlist_t *nvl, const char *name,
uint16_t *val);

int nvlist_lookup_int32(nvlist_t *nvl, const char *name,
int32_t *val);

int nvlist_lookup_uint32(nvlist_t *nvl, const char *name,
uint32_t *val);

int nvlist_lookup_int64(nvlist_t *nvl, const char *name,
int64_t *val);

int nvlist_lookup_uint64(nvlist_t *nvl, const char *name,
uint64_t *val);

int nvlist_lookup_string(nvlist_t *nvl, const char *name,
char **val);

int nvlist_lookup_nvlist(nvlist_t *nvl, const char *name,
nvlist_t **val);

int nvlist_lookup_boolean_array(nvlist_t *nvl, const char *name,
boolean_t **val, uint_t *nelem);

int nvlist_lookup_byte_array(nvlist_t *nvl, const char *name,
uchar_t **val, uint_t *nelem);

int nvlist_lookup_int8_array(nvlist_t *nvl, const char *name,
int8_t **val, uint_t *nelem);

int nvlist_lookup_uint8_array(nvlist_t *nvl, const char *name,
uint8_t **val, uint_t *nelem);

int nvlist_lookup_int16_array(nvlist_t *nvl, const char *name,
int16_t **val, uint_t *nelem);

int nvlist_lookup_uint16_array(nvlist_t *nvl, const char *name,
uint16_t **val, uint_t *nelem);

int nvlist_lookup_int32_array(nvlist_t *nvl, const char *name,
int32_t **val, uint_t *nelem);

int nvlist_lookup_uint32_array(nvlist_t *nvl, const char *name,
uint32_t **val, uint_t *nelem);

int nvlist_lookup_int64_array(nvlist_t *nvl, const char *name,
int64_t **val, uint_t *nelem);

int nvlist_lookup_uint64_array(nvlist_t *nvl, const char *name,
uint64_t **val, uint_t *nelem);

int nvlist_lookup_string_array(nvlist_t *nvl, const char *name,
char ***val, uint_t *nelem);

int nvlist_lookup_nvlist_array(nvlist_t *nvl, const char *name,
nvlist_t ***val, uint_t *nelem);

int nvlist_lookup_pairs(nvlist_t *nvl, int flag, ...);

INTERFACE LEVEL

illumos DDI specific (illumos DDI)

PARAMETERS

nvl
The list of name-value pairs (nvlist_t) to be processed.

name
Name of the name-value pair (nvpair) to search.

nelem
Address to store the number of elements in value.

val
Address to store the value or starting address of the array
value.

flag
Specify bit fields defining lookup behavior:

NV_FLAG_NOENTOK
The retrieval function will not fail if no
matching name-value pair is found.

DESCRIPTION

These functions find the nvpair that matches the name and type as
indicated by the interface name. If one is found, nelem and val are
modified to contain the number of elements in value and the starting
address of data, respectively.

These interfaces work for nvlist_t allocated with NV_UNIQUE_NAME or
NV_UNIQUE_NAME_TYPE specified in nvlist_alloc(). See nvlist_alloc(9F). If
this is not the case, the interface will return ENOTSUP because the list
potentially contains multiple nvpairs with the same name and type.

Multiple threads can simultaneously read the same nvlist_t but only one
thread should actively change a given nvlist_t at a time. The caller is
responsible for the synchronization.

All memory required for storing the array elements, including string
values, are managed by the library. References to such data remain valid
until nvlist_free() is called on nvl.

The nvlist_lookup_pairs() function retrieves a set of nvpairs. The
arguments are a null-terminated list of pairs (data type
DATA_TYPE_BOOLEAN), triples (non-array data types) or quads (array data
types). As shown below, the interpretation of the arguments depends on
the value of type. See nvpair_type(9F).

name
Name of the name-value pair to search.

type
Data type.

val
Address to store the starting address of the value. When using
data type DATA_TYPE_BOOLEAN, the val argument is ignored.

nelem
Address to store the number of elements in value. Non-array data
types have only one argument and nelem is ignored.

The argument order is name, type, [val], [nelem].

When using NV_FLAG_NOENTOK and no matching name-value pair is found, the
memory pointed to by val and nelem is not touched.

These functions return 0 on success and an error value on failure.

ERRORS

These functions fail under the following conditions.

0
Success.

EINVAL
Invalid argument.

ENOENT
No matching name-value pair found.

ENOTSUP
Encode/decode method not supported.

CONTEXT

These functions can be called from user, interrupt, or kernel context.

ATTRIBUTES