mirror of
https://github.com/HDFGroup/hdf5.git
synced 2025-03-07 16:37:56 +08:00
529 lines
23 KiB
C
529 lines
23 KiB
C
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
|
|
* Copyright by The HDF Group. *
|
|
* Copyright by the Board of Trustees of the University of Illinois. *
|
|
* All rights reserved. *
|
|
* *
|
|
* This file is part of HDF5. The full HDF5 copyright notice, including *
|
|
* terms governing use, modification, and redistribution, is contained in *
|
|
* the COPYING file, which can be found at the root of the source code *
|
|
* distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases. *
|
|
* If you do not have access to either file, you may request a copy from *
|
|
* help@hdfgroup.org. *
|
|
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
|
|
|
|
/****************/
|
|
/* Module Setup */
|
|
/****************/
|
|
|
|
#define H5G_FRIEND /*suppress error about including H5Gpkg */
|
|
#include "H5Lmodule.h" /* This source code file is part of the H5L module */
|
|
|
|
|
|
/***********/
|
|
/* Headers */
|
|
/***********/
|
|
#include "H5private.h" /* Generic Functions */
|
|
#include "H5ACprivate.h" /* Metadata cache */
|
|
#include "H5CXprivate.h" /* API Contexts */
|
|
#include "H5Eprivate.h" /* Error handling */
|
|
#include "H5Fprivate.h" /* Files */
|
|
#include "H5Gpkg.h" /* Groups */
|
|
#include "H5Iprivate.h" /* IDs */
|
|
#include "H5Lpkg.h" /* Links */
|
|
#include "H5MMprivate.h" /* Memory management */
|
|
#include "H5Opublic.h" /* File objects */
|
|
#include "H5Pprivate.h" /* Property lists */
|
|
#include "H5VLprivate.h" /* Virtual Object Layer */
|
|
|
|
|
|
/****************/
|
|
/* Local Macros */
|
|
/****************/
|
|
|
|
/* Version of external link format */
|
|
#define H5L_EXT_VERSION 0
|
|
|
|
/* Valid flags for external links */
|
|
#define H5L_EXT_FLAGS_ALL 0
|
|
|
|
/* Size of local link name buffer for traversing external links */
|
|
#define H5L_EXT_TRAVERSE_BUF_SIZE 256
|
|
|
|
|
|
/******************/
|
|
/* Local Typedefs */
|
|
/******************/
|
|
|
|
|
|
/********************/
|
|
/* Local Prototypes */
|
|
/********************/
|
|
static hid_t H5L__extern_traverse(const char *link_name, hid_t cur_group,
|
|
const void *udata, size_t udata_size, hid_t lapl_id, hid_t dxpl_id);
|
|
static ssize_t H5L__extern_query(const char *link_name, const void *udata,
|
|
size_t udata_size, void * buf /*out*/, size_t buf_size);
|
|
|
|
|
|
/*********************/
|
|
/* Package Variables */
|
|
/*********************/
|
|
|
|
|
|
/*****************************/
|
|
/* Library Private Variables */
|
|
/*****************************/
|
|
|
|
|
|
/*******************/
|
|
/* Local Variables */
|
|
/*******************/
|
|
|
|
/* Default External Link link class */
|
|
static const H5L_class_t H5L_EXTERN_LINK_CLASS[1] = {{
|
|
H5L_LINK_CLASS_T_VERS, /* H5L_class_t version */
|
|
H5L_TYPE_EXTERNAL, /* Link type id number */
|
|
"external", /* Link name for debugging */
|
|
NULL, /* Creation callback */
|
|
NULL, /* Move callback */
|
|
NULL, /* Copy callback */
|
|
H5L__extern_traverse, /* The actual traversal function */
|
|
NULL, /* Deletion callback */
|
|
H5L__extern_query /* Query callback */
|
|
}};
|
|
|
|
/*-------------------------------------------------------------------------
|
|
* Function: H5L__extern_traverse
|
|
*
|
|
* Purpose: Default traversal function for external links. This can
|
|
* be overridden using H5Lregister().
|
|
*
|
|
* Given a filename and path packed into the link udata,
|
|
* attempts to open an object within an external file.
|
|
* If the H5L_ELINK_PREFIX_NAME property is set in the
|
|
* link access property list, appends that prefix to the
|
|
* filename being opened.
|
|
*
|
|
* Return: ID of the opened object on success/H5I_INVALID_HID on failure
|
|
*
|
|
* Programmer: James Laird
|
|
* Monday, July 10, 2006
|
|
*
|
|
*-------------------------------------------------------------------------
|
|
*/
|
|
static hid_t
|
|
H5L__extern_traverse(const char H5_ATTR_UNUSED *link_name, hid_t cur_group,
|
|
const void *_udata, size_t H5_ATTR_UNUSED udata_size, hid_t lapl_id,
|
|
hid_t H5_ATTR_UNUSED dxpl_id)
|
|
{
|
|
H5P_genplist_t *plist; /* Property list pointer */
|
|
H5G_loc_t root_loc; /* Location of root group in external file */
|
|
H5G_loc_t loc; /* Location of object */
|
|
H5F_t *ext_file = NULL; /* File struct for external file */
|
|
const uint8_t *p = (const uint8_t *)_udata; /* Pointer into external link buffer */
|
|
const char *file_name; /* Name of file containing external link's object */
|
|
const char *obj_name; /* Name external link's object */
|
|
size_t fname_len; /* Length of external link file name */
|
|
unsigned intent; /* File access permissions */
|
|
H5L_elink_cb_t cb_info; /* Callback info struct */
|
|
hid_t fapl_id = -1; /* File access property list for external link's file */
|
|
void *ext_obj = NULL; /* External link's object */
|
|
hid_t ext_obj_id = H5I_INVALID_HID; /* ID for external link's object */
|
|
H5I_type_t opened_type; /* ID type of external link's object */
|
|
char *parent_group_name = NULL;/* Temporary pointer to group name */
|
|
char local_group_name[H5L_EXT_TRAVERSE_BUF_SIZE]; /* Local buffer to hold group name */
|
|
H5P_genplist_t *fa_plist; /* File access property list pointer */
|
|
H5F_close_degree_t fc_degree = H5F_CLOSE_WEAK; /* File close degree for target file */
|
|
char *elink_prefix = NULL; /* Pointer to elink prefix */
|
|
hid_t ret_value = H5I_INVALID_HID; /* Return value */
|
|
|
|
FUNC_ENTER_STATIC
|
|
|
|
/* Sanity checks */
|
|
HDassert(p);
|
|
|
|
/* Check external link version & flags */
|
|
if(((*p >> 4) & 0x0F) > H5L_EXT_VERSION)
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTDECODE, H5I_INVALID_HID, "bad version number for external link")
|
|
if((*p & 0x0F) & ~H5L_EXT_FLAGS_ALL)
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTDECODE, H5I_INVALID_HID, "bad flags for external link")
|
|
p++;
|
|
|
|
/* Gather some information from the external link's user data */
|
|
file_name = (const char *)p;
|
|
fname_len = HDstrlen(file_name);
|
|
obj_name = (const char *)p + fname_len + 1;
|
|
|
|
/* Get the plist structure */
|
|
if(NULL == (plist = H5P_object_verify(lapl_id, H5P_LINK_ACCESS)))
|
|
HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, H5I_INVALID_HID, "can't find object for ID")
|
|
|
|
/* Get the fapl_id set for lapl_id if any */
|
|
if(H5P_get(plist, H5L_ACS_ELINK_FAPL_NAME, &fapl_id) < 0)
|
|
HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, H5I_INVALID_HID, "can't get fapl for links")
|
|
|
|
/* Get the location for the group holding the external link */
|
|
if(H5G_loc(cur_group, &loc) < 0)
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTGET, H5I_INVALID_HID, "can't get object location")
|
|
|
|
/* get the access flags set for lapl_id if any */
|
|
if(H5P_get(plist, H5L_ACS_ELINK_FLAGS_NAME, &intent) < 0)
|
|
HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, H5I_INVALID_HID, "can't get elink file access flags")
|
|
|
|
/* get the file access mode flags for the parent file, if they were not set
|
|
* on lapl_id */
|
|
if(intent == H5F_ACC_DEFAULT)
|
|
intent = H5F_INTENT(loc.oloc->file);
|
|
|
|
if((fapl_id == H5P_DEFAULT) && ((fapl_id = H5F_get_access_plist(loc.oloc->file, FALSE)) < 0))
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTGET, H5I_INVALID_HID, "can't get parent's file access property list")
|
|
|
|
/* Get callback_info */
|
|
if(H5P_get(plist, H5L_ACS_ELINK_CB_NAME, &cb_info) < 0)
|
|
HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, H5I_INVALID_HID, "can't get elink callback info")
|
|
|
|
/* Get file access property list */
|
|
if(NULL == (fa_plist = H5P_object_verify(fapl_id, H5P_FILE_ACCESS)))
|
|
HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, H5I_INVALID_HID, "can't find object for ID")
|
|
|
|
/* Make callback if it exists */
|
|
if(cb_info.func) {
|
|
const char *parent_file_name; /* Parent file name */
|
|
ssize_t group_name_len; /* Length of parent group name */
|
|
|
|
/* Get parent file name */
|
|
parent_file_name = H5F_OPEN_NAME(loc.oloc->file);
|
|
|
|
/* Query length of parent group name */
|
|
if((group_name_len = H5G_get_name(&loc, NULL, (size_t) 0, NULL)) < 0)
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTGET, H5I_INVALID_HID, "unable to retrieve length of group name")
|
|
|
|
/* Account for null terminator */
|
|
group_name_len++;
|
|
|
|
/* Check if we need to allocate larger buffer */
|
|
if((size_t)group_name_len > sizeof(local_group_name)) {
|
|
if(NULL == (parent_group_name = (char *)H5MM_malloc((size_t)group_name_len)))
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTALLOC, H5I_INVALID_HID, "can't allocate buffer to hold group name, group_name_len = %zd", group_name_len)
|
|
} /* end if */
|
|
else
|
|
parent_group_name = local_group_name;
|
|
|
|
/* Get parent group name */
|
|
if(H5G_get_name(&loc, parent_group_name, (size_t) group_name_len, NULL) < 0)
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTGET, H5I_INVALID_HID, "unable to retrieve group name")
|
|
|
|
/* Make callback */
|
|
if((cb_info.func)(parent_file_name, parent_group_name, file_name, obj_name, &intent, fapl_id, cb_info.user_data) < 0)
|
|
HGOTO_ERROR(H5E_LINK, H5E_CALLBACK, H5I_INVALID_HID, "traversal operator failed")
|
|
|
|
/* Check access flags */
|
|
if((intent & H5F_ACC_TRUNC) || (intent & H5F_ACC_EXCL))
|
|
HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid file open flags")
|
|
} /* end if */
|
|
|
|
/* Set file close degree for new file to "weak" */
|
|
if(H5P_set(fa_plist, H5F_ACS_CLOSE_DEGREE_NAME, &fc_degree) < 0)
|
|
HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, H5I_INVALID_HID, "can't set file close degree")
|
|
|
|
/* Get the current elink prefix */
|
|
if(H5P_peek(plist, H5L_ACS_ELINK_PREFIX_NAME, &elink_prefix) < 0)
|
|
HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, H5I_INVALID_HID, "can't get external link prefix")
|
|
|
|
/* Search for the target file */
|
|
if(NULL == (ext_file = H5F_prefix_open_file(loc.oloc->file, H5F_PREFIX_ELINK, elink_prefix, file_name, intent, fapl_id)))
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTOPENFILE, H5I_INVALID_HID, "unable to open external file, external link file name = '%s'", file_name)
|
|
|
|
/* Retrieve the "group location" for the file's root group */
|
|
if(H5G_root_loc(ext_file, &root_loc) < 0)
|
|
HGOTO_ERROR(H5E_LINK, H5E_BADVALUE, H5I_INVALID_HID, "unable to create location for file")
|
|
|
|
/* Open the object referenced in the external file */
|
|
if(NULL == (ext_obj = H5O_open_name(&root_loc, obj_name, &opened_type)))
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTOPENOBJ, H5I_INVALID_HID, "unable to open object")
|
|
|
|
/* Get an ID for the external link's object */
|
|
if((ext_obj_id = H5VL_wrap_register(opened_type, ext_obj, TRUE)) < 0)
|
|
HGOTO_ERROR(H5E_ATOM, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to register external link object")
|
|
|
|
/* Set return value */
|
|
ret_value = ext_obj_id;
|
|
|
|
done:
|
|
/* XXX (VOL MERGE): Probably also want to consider closing ext_obj here on failures */
|
|
/* Release resources */
|
|
if(fapl_id > 0 && H5I_dec_ref(fapl_id) < 0)
|
|
HDONE_ERROR(H5E_ATOM, H5E_CANTRELEASE, H5I_INVALID_HID, "unable to close atom for file access property list")
|
|
if(ext_file && H5F_efc_close(loc.oloc->file, ext_file) < 0)
|
|
HDONE_ERROR(H5E_LINK, H5E_CANTCLOSEFILE, H5I_INVALID_HID, "problem closing external file")
|
|
if(parent_group_name && parent_group_name != local_group_name)
|
|
parent_group_name = (char *)H5MM_xfree(parent_group_name);
|
|
if(ret_value < 0) {
|
|
/* Close object if it's open and something failed */
|
|
if(ext_obj_id >= 0 && H5I_dec_ref(ext_obj_id) < 0)
|
|
HDONE_ERROR(H5E_ATOM, H5E_CANTRELEASE, H5I_INVALID_HID, "unable to close atom for external object")
|
|
} /* end if */
|
|
|
|
FUNC_LEAVE_NOAPI(ret_value)
|
|
} /* end H5L__extern_traverse() */
|
|
|
|
|
|
/*-------------------------------------------------------------------------
|
|
* Function: H5L__extern_query
|
|
*
|
|
* Purpose: Default query function for external links. This can
|
|
* be overridden using H5Lregister().
|
|
*
|
|
* Returns the size of the link's user data. If a buffer of
|
|
* is provided, copies at most buf_size bytes of the udata
|
|
* into it.
|
|
*
|
|
* Return: Size of buffer on success/Negative on failure
|
|
*
|
|
* Programmer: James Laird
|
|
* Monday, July 10, 2006
|
|
*
|
|
*-------------------------------------------------------------------------
|
|
*/
|
|
static ssize_t
|
|
H5L__extern_query(const char H5_ATTR_UNUSED * link_name, const void *_udata, size_t udata_size,
|
|
void *buf /*out*/, size_t buf_size)
|
|
{
|
|
const uint8_t *udata = (const uint8_t *)_udata; /* Pointer to external link buffer */
|
|
ssize_t ret_value = SUCCEED; /* Return value */
|
|
|
|
FUNC_ENTER_NOAPI_NOINIT
|
|
|
|
/* Check external link version & flags */
|
|
if(((*udata >> 4) & 0x0F) != H5L_EXT_VERSION)
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTDECODE, FAIL, "bad version number for external link")
|
|
if((*udata & 0x0F) & ~H5L_EXT_FLAGS_ALL)
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTDECODE, FAIL, "bad flags for external link")
|
|
|
|
/* If the buffer is NULL, skip writing anything in it and just return
|
|
* the size needed */
|
|
if(buf) {
|
|
if(udata_size < buf_size)
|
|
buf_size = udata_size;
|
|
|
|
/* Copy the udata verbatim up to buf_size */
|
|
H5MM_memcpy(buf, udata, buf_size);
|
|
} /* end if */
|
|
|
|
/* Set return value */
|
|
ret_value = (ssize_t)udata_size;
|
|
|
|
done:
|
|
FUNC_LEAVE_NOAPI(ret_value)
|
|
} /* end H5L__extern_query() */
|
|
|
|
|
|
/*-------------------------------------------------------------------------
|
|
* Function: H5Lcreate_external
|
|
*
|
|
* Purpose: Creates an external link from LINK_NAME to OBJ_NAME.
|
|
*
|
|
* External links are links to objects in other HDF5 files. They
|
|
* are allowed to "dangle" like soft links internal to a file.
|
|
* FILE_NAME is the name of the file that OBJ_NAME is is contained
|
|
* within. If OBJ_NAME is given as a relative path name, the
|
|
* path will be relative to the root group of FILE_NAME.
|
|
* LINK_NAME is interpreted relative to LINK_LOC_ID, which is
|
|
* either a file ID or a group ID.
|
|
*
|
|
* Return: Non-negative on success/Negative on failure
|
|
*
|
|
* Programmer: Quincey Koziol
|
|
* Wednesday, May 18, 2005
|
|
*
|
|
*-------------------------------------------------------------------------
|
|
*/
|
|
herr_t
|
|
H5Lcreate_external(const char *file_name, const char *obj_name,
|
|
hid_t link_loc_id, const char *link_name, hid_t lcpl_id, hid_t lapl_id)
|
|
{
|
|
H5VL_object_t *vol_obj = NULL; /* Object of loc_id */
|
|
H5VL_loc_params_t loc_params;
|
|
char *norm_obj_name = NULL; /* Pointer to normalized current name */
|
|
void *ext_link_buf = NULL; /* Buffer to contain external link */
|
|
size_t buf_size; /* Size of buffer to hold external link */
|
|
size_t file_name_len; /* Length of file name string */
|
|
size_t norm_obj_name_len; /* Length of normalized object name string */
|
|
uint8_t *p; /* Pointer into external link buffer */
|
|
H5L_type_t link_type = H5L_TYPE_EXTERNAL;
|
|
herr_t ret_value = SUCCEED; /* Return value */
|
|
|
|
FUNC_ENTER_API(FAIL)
|
|
H5TRACE6("e", "*s*si*sii", file_name, obj_name, link_loc_id, link_name,
|
|
lcpl_id, lapl_id);
|
|
|
|
/* Check arguments */
|
|
if(!file_name || !*file_name)
|
|
HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no file name specified")
|
|
if(!obj_name || !*obj_name)
|
|
HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no object name specified")
|
|
if(!link_name || !*link_name)
|
|
HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no link name specified")
|
|
|
|
/* Get the link creation property list */
|
|
if(H5P_DEFAULT == lcpl_id)
|
|
lcpl_id = H5P_LINK_CREATE_DEFAULT;
|
|
|
|
/* Set the LCPL for the API context */
|
|
H5CX_set_lcpl(lcpl_id);
|
|
|
|
/* Verify access property list and set up collective metadata if appropriate */
|
|
if(H5CX_set_apl(&lapl_id, H5P_CLS_LACC, link_loc_id, TRUE) < 0)
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTSET, FAIL, "can't set access property list info")
|
|
|
|
/* Get normalized copy of the link target */
|
|
if(NULL == (norm_obj_name = H5G_normalize(obj_name)))
|
|
HGOTO_ERROR(H5E_LINK, H5E_BADVALUE, FAIL, "can't normalize object name")
|
|
|
|
/* Combine the filename and link name into a single buffer to give to the UD link */
|
|
file_name_len = HDstrlen(file_name) + 1;
|
|
norm_obj_name_len = HDstrlen(norm_obj_name) + 1;
|
|
buf_size = 1 + file_name_len + norm_obj_name_len;
|
|
if(NULL == (ext_link_buf = H5MM_malloc(buf_size)))
|
|
HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "unable to allocate udata buffer")
|
|
|
|
/* Encode the external link information */
|
|
p = (uint8_t *)ext_link_buf;
|
|
*p++ = (H5L_EXT_VERSION << 4) | H5L_EXT_FLAGS_ALL; /* External link version & flags */
|
|
HDstrncpy((char *)p, file_name, buf_size - 1); /* Name of file containing external link's object */
|
|
p += file_name_len;
|
|
HDstrncpy((char *)p, norm_obj_name, buf_size - (file_name_len + 1)); /* External link's object */
|
|
|
|
loc_params.type = H5VL_OBJECT_BY_NAME;
|
|
loc_params.loc_data.loc_by_name.name = link_name;
|
|
loc_params.loc_data.loc_by_name.lapl_id = lapl_id;
|
|
loc_params.obj_type = H5I_get_type(link_loc_id);
|
|
|
|
/* get the location object */
|
|
if(NULL == (vol_obj = (H5VL_object_t *)H5I_object(link_loc_id)))
|
|
HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid object identifier")
|
|
|
|
/* Create an external link */
|
|
if(H5VL_link_create(H5VL_LINK_CREATE_UD, vol_obj, &loc_params, lcpl_id, lapl_id, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, (int)link_type, ext_link_buf, buf_size) < 0)
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTINIT, FAIL, "unable to create external link")
|
|
|
|
done:
|
|
H5MM_xfree(ext_link_buf);
|
|
H5MM_xfree(norm_obj_name);
|
|
|
|
FUNC_LEAVE_API(ret_value)
|
|
} /* end H5Lcreate_external() */
|
|
|
|
|
|
/*-------------------------------------------------------------------------
|
|
* Function: H5L_register_external
|
|
*
|
|
* Purpose: Registers default "External Link" link class.
|
|
* Use during library initialization or to restore the default
|
|
* after users change it.
|
|
*
|
|
* Return: Non-negative on success/ negative on failure
|
|
*
|
|
* Programmer: James Laird
|
|
* Monday, July 17, 2006
|
|
*
|
|
*-------------------------------------------------------------------------
|
|
*/
|
|
herr_t
|
|
H5L_register_external(void)
|
|
{
|
|
herr_t ret_value = SUCCEED; /* Return value */
|
|
|
|
FUNC_ENTER_NOAPI(FAIL)
|
|
|
|
if(H5L_register(H5L_EXTERN_LINK_CLASS) < 0)
|
|
HGOTO_ERROR(H5E_LINK, H5E_NOTREGISTERED, FAIL, "unable to register external link class")
|
|
|
|
done:
|
|
FUNC_LEAVE_NOAPI(ret_value)
|
|
} /* end H5L_register_external() */
|
|
|
|
|
|
/*-------------------------------------------------------------------------
|
|
* Function: H5Lunpack_elink_val
|
|
*
|
|
* Purpose: Given a buffer holding the "link value" from an external link,
|
|
* gets pointers to the information within the link value buffer.
|
|
*
|
|
* External link link values contain some flags and
|
|
* two NULL-terminated strings, one after the other.
|
|
*
|
|
* The FLAGS value will be filled in and FILENAME and
|
|
* OBJ_PATH will be set to pointers within ext_linkval (unless
|
|
* any of these values is NULL).
|
|
*
|
|
* Using this function on strings that aren't external link
|
|
* udata buffers can result in segmentation faults.
|
|
*
|
|
* Return: Non-negative on success/ Negative on failure
|
|
*
|
|
* Programmer: James Laird
|
|
* Monday, July 17, 2006
|
|
*
|
|
*-------------------------------------------------------------------------
|
|
*/
|
|
herr_t
|
|
H5Lunpack_elink_val(const void *_ext_linkval, size_t link_size,
|
|
unsigned *flags, const char **filename, const char **obj_path)
|
|
{
|
|
const uint8_t *ext_linkval = (const uint8_t *)_ext_linkval; /* Pointer to the link value */
|
|
unsigned lnk_version; /* External link format version */
|
|
unsigned lnk_flags; /* External link flags */
|
|
size_t len; /* Length of the filename in the linkval*/
|
|
herr_t ret_value = SUCCEED; /* Return value */
|
|
|
|
FUNC_ENTER_API(FAIL)
|
|
H5TRACE5("e", "*xz*Iu**s**s", _ext_linkval, link_size, flags, filename,
|
|
obj_path);
|
|
|
|
/* Sanity check external link buffer */
|
|
if(ext_linkval == NULL )
|
|
HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not an external link linkval buffer")
|
|
lnk_version = (*ext_linkval >> 4) & 0x0F;
|
|
lnk_flags = *ext_linkval & 0x0F;
|
|
if(lnk_version > H5L_EXT_VERSION)
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTDECODE, FAIL, "bad version number for external link")
|
|
if(lnk_flags & (unsigned)~H5L_EXT_FLAGS_ALL)
|
|
HGOTO_ERROR(H5E_LINK, H5E_CANTDECODE, FAIL, "bad flags for external link")
|
|
if(link_size <= 2)
|
|
HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not a valid external link buffer")
|
|
|
|
/* Try to do some error checking. If the last character in the linkval
|
|
* (the last character of obj_path) isn't NULL, then something's wrong.
|
|
*/
|
|
if(ext_linkval[link_size - 1] != '\0')
|
|
HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "linkval buffer is not NULL-terminated")
|
|
|
|
/* We're now guaranteed that HDstrlen won't segfault, since the buffer has
|
|
* at least one NULL in it.
|
|
*/
|
|
len = HDstrlen((const char *)ext_linkval + 1);
|
|
|
|
/* If the first NULL we found was at the very end of the buffer, then
|
|
* this external link value has no object name and is invalid.
|
|
*/
|
|
if((len + 1) >= (link_size - 1))
|
|
HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "linkval buffer doesn't contain an object path")
|
|
|
|
/* If we got here then the buffer contains (at least) two strings packed
|
|
* in the correct way. Assume it's correct and return pointers to the
|
|
* filename and object path.
|
|
*/
|
|
if(filename)
|
|
*filename = (const char *)ext_linkval + 1;
|
|
if(obj_path)
|
|
*obj_path = ((const char *)ext_linkval + 1) + len + 1; /* Add one for NULL terminator */
|
|
|
|
/* Set the flags to return */
|
|
if(flags)
|
|
*flags = lnk_flags;
|
|
|
|
done:
|
|
FUNC_LEAVE_API(ret_value)
|
|
} /* end H5Lunpack_elink_val() */
|
|
|