_int_dlopen: libcapsule Reference Manual

_int_dlopen

Functions

return	capsule_shim_dlopen ()
return	capsule_shim_realloc ()

Description

Functions

capsule_shim_dlopen ()

return
capsule_shim_dlopen (cap Param1,
                     filename Param2,
                     flag Param3);

Parameters

cap	The capsule from which `dlopen` was called
file	SONAME or filename to be opened
flag	`dlopen` flags to pass to the real `dlopen` call

Returns

A handle as if for dlopen

An implementation of dlopen suitable to be called from inside a namespace. Load file into cap namespace.

If cap has a non-trivial prefix, load file and its recursive dependencies from cap prefix instead of from the root filesystem.

This helper function exists because dlopen() cannot safely be called by a DSO opened into a private namespace. It takes file and flag arguments cf dlopen() and a cap handle, and performs a safe dlmopen() call instead.

Typically this function is used to implement a safe wrapper for dlopen() which is assigned to the int_dlopen member of the capsule_metadata. This * replaces calls to dlopen() by all DSOs in the capsule, allowing libraries which use dlopen() to work inside the capsule.

Limitations: RTLD_GLOBAL is not supported in flag . This is a glibc limitation in the dlmopen() implementation.

capsule_shim_realloc ()

return
capsule_shim_realloc (cap Param1,
                      ptr Param2,
                      size Param3);