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Portable Hardware Locality (hwloc) Documentation: v1.9

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Exporting Topologies to XML

Functions

int hwloc_topology_export_xml (hwloc_topology_t topology, const char *xmlpath)
 
int hwloc_topology_export_xmlbuffer (hwloc_topology_t topology, char **xmlbuffer, int *buflen)
 
void hwloc_free_xmlbuffer (hwloc_topology_t topology, char *xmlbuffer)
 
void hwloc_topology_set_userdata_export_callback (hwloc_topology_t topology, void(*export_cb)(void *reserved, hwloc_topology_t topology, hwloc_obj_t obj))
 
int hwloc_export_obj_userdata (void *reserved, hwloc_topology_t topology, hwloc_obj_t obj, const char *name, const void *buffer, size_t length)
 
int hwloc_export_obj_userdata_base64 (void *reserved, hwloc_topology_t topology, hwloc_obj_t obj, const char *name, const void *buffer, size_t length)
 
void hwloc_topology_set_userdata_import_callback (hwloc_topology_t topology, void(*import_cb)(hwloc_topology_t topology, hwloc_obj_t obj, const char *name, const void *buffer, size_t length))
 

Detailed Description

Function Documentation

int hwloc_export_obj_userdata ( void *  reserved,
hwloc_topology_t  topology,
hwloc_obj_t  obj,
const char *  name,
const void *  buffer,
size_t  length 
)

Export some object userdata to XML.

This function may only be called from within the export() callback passed to hwloc_topology_set_userdata_export_callback(). It may be invoked one of multiple times to export some userdata to XML. The buffer content of length length is stored with optional name name.

When importing this XML file, the import() callback (if set) will be called exactly as many times as hwloc_export_obj_userdata() was called during export(). It will receive the corresponding name, buffer and length arguments.

reserved, topology and obj must be the first three parameters that were given to the export callback.

Only printable characters may be exported to XML string attributes. If a non-printable character is passed in name or buffer, the function returns -1 with errno set to EINVAL.

If exporting binary data, the application should first encode into printable characters only (or use hwloc_export_obj_userdata_base64()). It should also take care of portability issues if the export may be reimported on a different architecture.

int hwloc_export_obj_userdata_base64 ( void *  reserved,
hwloc_topology_t  topology,
hwloc_obj_t  obj,
const char *  name,
const void *  buffer,
size_t  length 
)

Encode and export some object userdata to XML.

This function is similar to hwloc_export_obj_userdata() but it encodes the input buffer into printable characters before exporting. On import, decoding is automatically performed before the data is given to the import() callback if any.

This function may only be called from within the export() callback passed to hwloc_topology_set_userdata_export_callback().

The function does not take care of portability issues if the export may be reimported on a different architecture.

void hwloc_free_xmlbuffer ( hwloc_topology_t  topology,
char *  xmlbuffer 
)

Free a buffer allocated by hwloc_topology_export_xmlbuffer()

int hwloc_topology_export_xml ( hwloc_topology_t  topology,
const char *  xmlpath 
)

Export the topology into an XML file.

This file may be loaded later through hwloc_topology_set_xml().

Returns
-1 if a failure occured.
Note
See also hwloc_topology_set_userdata_export_callback() for exporting application-specific userdata.
Only printable characters may be exported to XML string attributes. Any other character, especially any non-ASCII character, will be silently dropped.
If name is "-", the XML output is sent to the standard output.
int hwloc_topology_export_xmlbuffer ( hwloc_topology_t  topology,
char **  xmlbuffer,
int *  buflen 
)

Export the topology into a newly-allocated XML memory buffer.

xmlbuffer is allocated by the callee and should be freed with hwloc_free_xmlbuffer() later in the caller.

This memory buffer may be loaded later through hwloc_topology_set_xmlbuffer().

Returns
-1 if a failure occured.
Note
See also hwloc_topology_set_userdata_export_callback() for exporting application-specific userdata.
Only printable characters may be exported to XML string attributes. Any other character, especially any non-ASCII character, will be silently dropped.
void hwloc_topology_set_userdata_export_callback ( hwloc_topology_t  topology,
void(*)(void *reserved, hwloc_topology_t topology, hwloc_obj_t obj)  export_cb 
)

Set the application-specific callback for exporting userdata.

The object userdata pointer is not exported to XML by default because hwloc does not know what it contains.

This function lets applications set export_cb to a callback function that converts this opaque userdata into an exportable string.

export_cb is invoked during XML export for each object whose userdata pointer is not NULL. The callback should use hwloc_export_obj_userdata() or hwloc_export_obj_userdata_base64() to actually export something to XML (possibly multiple times per object).

export_cb may be set to NULL if userdata should not be exported to XML.

void hwloc_topology_set_userdata_import_callback ( hwloc_topology_t  topology,
void(*)(hwloc_topology_t topology, hwloc_obj_t obj, const char *name, const void *buffer, size_t length)  import_cb 
)

Set the application-specific callback for importing userdata.

On XML import, userdata is ignored by default because hwloc does not know how to store it in memory.

This function lets applications set import_cb to a callback function that will get the XML-stored userdata and store it in the object as expected by the application.

import_cb is called during hwloc_topology_load() as many times as hwloc_export_obj_userdata() was called during export. The topology is not entirely setup yet. Object attributes are ready to consult, but links between objects are not.

import_cb may be NULL if userdata should be ignored during import.

Note
buffer contains length characters followed by a null byte ('\0').
This function should be called before hwloc_topology_load().