# Module libvirt-common from libvirt

Provides common macros and enums needed by both libvirt and libvirt-admin libraries

## Table of Contents

### Macros

    #define LIBVIR_CHECK_VERSION
    #define LIBVIR_VERSION_NUMBER
    #define VIR_TYPED_PARAM_FIELD_LENGTH

### Types

    typedef enum virConnectCloseReason
    typedef struct _virTypedParameter virTypedParameter
    typedef enum virTypedParameterFlags
    typedef virTypedParameter * virTypedParameterPtr
    typedef enum virTypedParameterType

### Functions

    typedef virFreeCallback
    void	virFreeCallback			(void * opaque)

    int	virTypedParamsAddBoolean	(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 int value)
    int	virTypedParamsAddDouble		(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 double value)
    int	virTypedParamsAddFromString	(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 int type,
    					 const char * value)
    int	virTypedParamsAddInt		(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 int value)
    int	virTypedParamsAddLLong		(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 long long value)
    int	virTypedParamsAddString		(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 const char * value)
    int	virTypedParamsAddStringList	(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 const char ** values)
    int	virTypedParamsAddUInt		(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 unsigned int value)
    int	virTypedParamsAddULLong		(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 unsigned long long value)
    void	virTypedParamsClear		(virTypedParameterPtr params,
    					 int nparams)
    void	virTypedParamsFree		(virTypedParameterPtr params,
    					 int nparams)
    virTypedParameterPtr	virTypedParamsGet	(virTypedParameterPtr params,
    						 int nparams,
    						 const char * name)
    int	virTypedParamsGetBoolean	(virTypedParameterPtr params,
    					 int nparams,
    					 const char * name,
    					 int * value)
    int	virTypedParamsGetDouble		(virTypedParameterPtr params,
    					 int nparams,
    					 const char * name,
    					 double * value)
    int	virTypedParamsGetInt		(virTypedParameterPtr params,
    					 int nparams,
    					 const char * name,
    					 int * value)
    int	virTypedParamsGetLLong		(virTypedParameterPtr params,
    					 int nparams,
    					 const char * name,
    					 long long * value)
    int	virTypedParamsGetString		(virTypedParameterPtr params,
    					 int nparams,
    					 const char * name,
    					 const char ** value)
    int	virTypedParamsGetUInt		(virTypedParameterPtr params,
    					 int nparams,
    					 const char * name,
    					 unsigned int * value)
    int	virTypedParamsGetULLong		(virTypedParameterPtr params,
    					 int nparams,
    					 const char * name,
    					 unsigned long long * value)

## Description

### Macros

### `LIBVIR_CHECK_VERSION`

    #define LIBVIR_CHECK_VERSION

Macro for developers to easily check what version of the library their code is compiling against. e.g. #if LIBVIR_CHECK_VERSION(1,1,3) // some code that only works in 1.1.3 and newer #endif

### `LIBVIR_VERSION_NUMBER`

    #define LIBVIR_VERSION_NUMBER

Macro providing the version of the library as version * 1,000,000 + minor * 1000 + micro

### `VIR_TYPED_PARAM_FIELD_LENGTH`

    #define VIR_TYPED_PARAM_FIELD_LENGTH

Macro providing the field length of virTypedParameter name

### Types

### `virConnectCloseReason`

    enum virConnectCloseReason {

VIR_CONNECT_CLOSE_REASON_ERROR | = | 0 (0x0) | Misc I/O error
VIR_CONNECT_CLOSE_REASON_EOF | = | 1 (0x1) | End-of-file from server
VIR_CONNECT_CLOSE_REASON_KEEPALIVE | = | 2 (0x2) | Keepalive timer triggered
VIR_CONNECT_CLOSE_REASON_CLIENT | = | 3 (0x3) | Client requested it
VIR_CONNECT_CLOSE_REASON_LAST | = | 4 (0x4)

    }

### `virTypedParameter`

    struct virTypedParameter {

char field[VIR_TYPED_PARAM_FIELD_LENGTH] | field | parameter name
int | type | parameter type, virTypedParameterType
union {
int | i | type is INT
unsigned int | ui | type is UINT
long long int | l | type is LLONG
unsigned long long int | ul | type is ULLONG
double | d | type is DOUBLE
char | b | type is BOOLEAN
char * | s | type is STRING, may not be NULL
} | value | parameter value |

    }

### `virTypedParameterFlags`

Flags related to libvirt APIs that use virTypedParameter. These enums should not conflict with those of virDomainModificationImpact.

    enum virTypedParameterFlags {

VIR_TYPED_PARAM_STRING_OKAY | = | 4 (0x4; 1 << 2) | 1 << 0 is reserved for virDomainModificationImpact 1 << 1 is reserved for virDomainModificationImpact Older servers lacked the ability to handle string typed parameters. Attempts to set a string parameter with an older server will fail at the client, but attempts to retrieve parameters must not return strings from a new server to an older client, so this flag exists to identify newer clients to newer servers. This flag is automatically set when needed, so the user does not have to worry about it; however, manually setting the flag can be used to reject servers that cannot return typed strings, even if no strings would be returned.

    }

### `virTypedParameterPtr`

    typedef virTypedParameter * virTypedParameterPtr;

a pointer to a virTypedParameter structure.

### `virTypedParameterType`

Express the type of a virTypedParameter

    enum virTypedParameterType {

VIR_TYPED_PARAM_INT | = | 1 (0x1) | integer case
VIR_TYPED_PARAM_UINT | = | 2 (0x2) | unsigned integer case
VIR_TYPED_PARAM_LLONG | = | 3 (0x3) | long long case
VIR_TYPED_PARAM_ULLONG | = | 4 (0x4) | unsigned long long case
VIR_TYPED_PARAM_DOUBLE | = | 5 (0x5) | double case
VIR_TYPED_PARAM_BOOLEAN | = | 6 (0x6) | boolean(character) case
VIR_TYPED_PARAM_STRING | = | 7 (0x7) | string case
VIR_TYPED_PARAM_LAST | = | 8 (0x8)

    }

### Functions

### `virFreeCallback`

    typedef void	(*virFreeCallback		)	(void * opaque)

Type for a callback cleanup function to be paired with a callback. This function will be called as a final chance to clean up the `opaque` registered with the primary callback, at the time when the primary callback is deregistered.

It is forbidden to call any other libvirt APIs from an implementation of this callback, since it can be invoked from a context which is not re-entrant safe. Failure to abide by this requirement may lead to application deadlocks or crashes.

opaque
  opaque user data provided at registration

### `virTypedParamsAddBoolean`

    int	virTypedParamsAddBoolean	(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 int value)

Adds new parameter called `name` with boolean type and sets its value to `value`. If `params` array points to NULL or to a space that is not large enough to accommodate the new parameter (`maxparams` < `nparams` + 1), the function allocates more space for it and updates `maxparams`. On success, `nparams` is incremented by one. The function fails with VIR_ERR_INVALID_ARG error if the parameter already exists in `params`.

params
  pointer to the array of typed parameters
nparams
  number of parameters in the `params` array
maxparams
  maximum number of parameters that can be stored in `params` array without allocating more memory
name
  name of the parameter to find
value
  the value to store into the new parameter
Returns
  0 on success, -1 on error.

### `virTypedParamsAddDouble`

    int	virTypedParamsAddDouble		(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 double value)

Adds new parameter called `name` with double type and sets its value to `value`. If `params` array points to NULL or to a space that is not large enough to accommodate the new parameter (`maxparams` < `nparams` + 1), the function allocates more space for it and updates `maxparams`. On success, `nparams` is incremented by one. The function fails with VIR_ERR_INVALID_ARG error if the parameter already exists in `params`.

params
  pointer to the array of typed parameters
nparams
  number of parameters in the `params` array
maxparams
  maximum number of parameters that can be stored in `params` array without allocating more memory
name
  name of the parameter to find
value
  the value to store into the new parameter
Returns
  0 on success, -1 on error.

### `virTypedParamsAddFromString`

    int	virTypedParamsAddFromString	(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 int type,
    					 const char * value)

Adds new parameter called `name` with the requested `type` and parses its value from the `value` string. If the requested type is string, the function creates its own copy of the `value` string, which needs to be freed using virTypedParamsFree or virTypedParamsClear. If `params` array points to NULL or to a space that is not large enough to accommodate the new parameter (`maxparams` < `nparams` + 1), the function allocates more space for it and updates `maxparams`. On success, `nparams` is incremented by one. The function fails with VIR_ERR_INVALID_ARG error if the parameter already exists in `params`.

params
  pointer to the array of typed parameters
nparams
  number of parameters in the `params` array
maxparams
  maximum number of parameters that can be stored in `params` array without allocating more memory
name
  name of the parameter to find
type
  type of the parameter
value
  the value to store into the new parameter encoded as a string
Returns
  0 on success, -1 on error.

### `virTypedParamsAddInt`

    int	virTypedParamsAddInt		(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 int value)

Adds new parameter called `name` with int type and sets its value to `value`. If `params` array points to NULL or to a space that is not large enough to accommodate the new parameter (`maxparams` < `nparams` + 1), the function allocates more space for it and updates `maxparams`. On success, `nparams` is incremented by one. The function fails with VIR_ERR_INVALID_ARG error if the parameter already exists in `params`.

params
  pointer to the array of typed parameters
nparams
  number of parameters in the `params` array
maxparams
  maximum number of parameters that can be stored in `params` array without allocating more memory
name
  name of the parameter to find
value
  the value to store into the new parameter
Returns
  0 on success, -1 on error.

### `virTypedParamsAddLLong`

    int	virTypedParamsAddLLong		(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 long long value)

Adds new parameter called `name` with long long int type and sets its value to `value`. If `params` array points to NULL or to a space that is not large enough to accommodate the new parameter (`maxparams` < `nparams` + 1), the function allocates more space for it and updates `maxparams`. On success, `nparams` is incremented by one. The function fails with VIR_ERR_INVALID_ARG error if the parameter already exists in `params`.

params
  pointer to the array of typed parameters
nparams
  number of parameters in the `params` array
maxparams
  maximum number of parameters that can be stored in `params` array without allocating more memory
name
  name of the parameter to find
value
  the value to store into the new parameter
Returns
  0 on success, -1 on error.

### `virTypedParamsAddString`

    int	virTypedParamsAddString		(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 const char * value)

Adds new parameter called `name` with char * type and sets its value to `value`. The function creates its own copy of `value` string, which needs to be freed using virTypedParamsFree or virTypedParamsClear. If `params` array points to NULL or to a space that is not large enough to accommodate the new parameter (`maxparams` < `nparams` + 1), the function allocates more space for it and updates `maxparams`. On success, `nparams` is incremented by one. The function fails with VIR_ERR_INVALID_ARG error if the parameter already exists in `params`.

params
  pointer to the array of typed parameters
nparams
  number of parameters in the `params` array
maxparams
  maximum number of parameters that can be stored in `params` array without allocating more memory
name
  name of the parameter to find
value
  the value to store into the new parameter
Returns
  0 on success, -1 on error.

### `virTypedParamsAddStringList`

    int	virTypedParamsAddStringList	(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 const char ** values)

Packs NULL-terminated list of strings `values` into `params` under the key `name`.

params
  array of typed parameters
nparams
  number of parameters in the `params` array
maxparams
  maximum number of parameters that can be stored in `params` array without allocating more memory
name
  name of the parameter to store values to
values
  the values to store into the new parameters
Returns
  0 on success, -1 on error.

### `virTypedParamsAddUInt`

    int	virTypedParamsAddUInt		(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 unsigned int value)

Adds new parameter called `name` with unsigned int type and sets its value to `value`. If `params` array points to NULL or to a space that is not large enough to accommodate the new parameter (`maxparams` < `nparams` + 1), the function allocates more space for it and updates `maxparams`. On success, `nparams` is incremented by one. The function fails with VIR_ERR_INVALID_ARG error if the parameter already exists in `params`.

params
  pointer to the array of typed parameters
nparams
  number of parameters in the `params` array
maxparams
  maximum number of parameters that can be stored in `params` array without allocating more memory
name
  name of the parameter to find
value
  the value to store into the new parameter
Returns
  0 on success, -1 on error.

### `virTypedParamsAddULLong`

    int	virTypedParamsAddULLong		(virTypedParameterPtr * params,
    					 int * nparams,
    					 int * maxparams,
    					 const char * name,
    					 unsigned long long value)

Adds new parameter called `name` with unsigned long long type and sets its value to `value`. If `params` array points to NULL or to a space that is not large enough to accommodate the new parameter (`maxparams` < `nparams` + 1), the function allocates more space for it and updates `maxparams`. On success, `nparams` is incremented by one. The function fails with VIR_ERR_INVALID_ARG error if the parameter already exists in `params`.

params
  pointer to the array of typed parameters
nparams
  number of parameters in the `params` array
maxparams
  maximum number of parameters that can be stored in `params` array without allocating more memory
name
  name of the parameter to find
value
  the value to store into the new parameter
Returns
  0 on success, -1 on error.

### `virTypedParamsClear`

    void	virTypedParamsClear		(virTypedParameterPtr params,
    					 int nparams)

Frees all memory used by string parameters. The memory occupied by `params` is not freed; use virTypedParamsFree if you want it to be freed too.

params
  the array of typed parameters
nparams
  number of parameters in the `params` array

### `virTypedParamsFree`

    void	virTypedParamsFree		(virTypedParameterPtr params,
    					 int nparams)

Frees all memory used by string parameters and the memory occupied by `params`.

params
  the array of typed parameters
nparams
  number of parameters in the `params` array

### `virTypedParamsGet`

    virTypedParameterPtr	virTypedParamsGet	(virTypedParameterPtr params,
    						 int nparams,
    						 const char * name)

Finds typed parameter called `name`.

params
  array of typed parameters
nparams
  number of parameters in the `params` array
name
  name of the parameter to find
Returns
  pointer to the parameter or NULL if it does not exist in `params`. This function does not raise an error, even when returning NULL.

### `virTypedParamsGetBoolean`

    int	virTypedParamsGetBoolean	(virTypedParameterPtr params,
    					 int nparams,
    					 const char * name,
    					 int * value)

Finds typed parameter called `name` and store its boolean value in `value`. The function fails with VIR_ERR_INVALID_ARG error if the parameter does not have the expected type. By passing NULL as `value`, the function may be used to check presence and type of the parameter.

params
  array of typed parameters
nparams
  number of parameters in the `params` array
name
  name of the parameter to find
value
  where to store the parameter's value
Returns
  1 on success, 0 when the parameter does not exist in `params`, or -1 on error.

### `virTypedParamsGetDouble`

    int	virTypedParamsGetDouble		(virTypedParameterPtr params,
    					 int nparams,
    					 const char * name,
    					 double * value)

Finds typed parameter called `name` and store its double value in `value`. The function fails with VIR_ERR_INVALID_ARG error if the parameter does not have the expected type. By passing NULL as `value`, the function may be used to check presence and type of the parameter.

params
  array of typed parameters
nparams
  number of parameters in the `params` array
name
  name of the parameter to find
value
  where to store the parameter's value
Returns
  1 on success, 0 when the parameter does not exist in `params`, or -1 on error.

### `virTypedParamsGetInt`

    int	virTypedParamsGetInt		(virTypedParameterPtr params,
    					 int nparams,
    					 const char * name,
    					 int * value)

Finds typed parameter called `name` and store its int value in `value`. The function fails with VIR_ERR_INVALID_ARG error if the parameter does not have the expected type. By passing NULL as `value`, the function may be used to check presence and type of the parameter.

params
  array of typed parameters
nparams
  number of parameters in the `params` array
name
  name of the parameter to find
value
  where to store the parameter's value
Returns
  1 on success, 0 when the parameter does not exist in `params`, or -1 on error.

### `virTypedParamsGetLLong`

    int	virTypedParamsGetLLong		(virTypedParameterPtr params,
    					 int nparams,
    					 const char * name,
    					 long long * value)

Finds typed parameter called `name` and store its long long int value in `value`. The function fails with VIR_ERR_INVALID_ARG error if the parameter does not have the expected type. By passing NULL as `value`, the function may be used to check presence and type of the parameter.

params
  array of typed parameters
nparams
  number of parameters in the `params` array
name
  name of the parameter to find
value
  where to store the parameter's value
Returns
  1 on success, 0 when the parameter does not exist in `params`, or -1 on error.

### `virTypedParamsGetString`

    int	virTypedParamsGetString		(virTypedParameterPtr params,
    					 int nparams,
    					 const char * name,
    					 const char ** value)

Finds typed parameter called `name` and store its char * value in `value`. The function does not create a copy of the string and the caller must not free the string `value` points to. The function fails with VIR_ERR_INVALID_ARG error if the parameter does not have the expected type. By passing NULL as `value`, the function may be used to check presence and type of the parameter.

params
  array of typed parameters
nparams
  number of parameters in the `params` array
name
  name of the parameter to find
value
  where to store the parameter's value
Returns
  1 on success, 0 when the parameter does not exist in `params`, or -1 on error.

### `virTypedParamsGetUInt`

    int	virTypedParamsGetUInt		(virTypedParameterPtr params,
    					 int nparams,
    					 const char * name,
    					 unsigned int * value)

Finds typed parameter called `name` and store its unsigned int value in `value`. The function fails with VIR_ERR_INVALID_ARG error if the parameter does not have the expected type. By passing NULL as `value`, the function may be used to check presence and type of the parameter.

params
  array of typed parameters
nparams
  number of parameters in the `params` array
name
  name of the parameter to find
value
  where to store the parameter's value
Returns
  1 on success, 0 when the parameter does not exist in `params`, or -1 on error.

### `virTypedParamsGetULLong`

    int	virTypedParamsGetULLong		(virTypedParameterPtr params,
    					 int nparams,
    					 const char * name,
    					 unsigned long long * value)

Finds typed parameter called `name` and store its unsigned long long int value in `value`. The function fails with VIR_ERR_INVALID_ARG error if the parameter does not have the expected type. By passing NULL as `value`, the function may be used to check presence and type of the parameter.

params
  array of typed parameters
nparams
  number of parameters in the `params` array
name
  name of the parameter to find
value
  where to store the parameter's value
Returns
  1 on success, 0 when the parameter does not exist in `params`, or -1 on error.