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* lib: Check return value of rib_initDimitri Staessens2022-03-031-1/+6
| | | | | | | The rib_init return value wasn't checked. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Encrypt bare FRCP messages on encrypted flowsDimitri Staessens2022-03-031-2/+1
| | | | | | | | Bare FRCP messages (ACKs without data, Rendez-vous packets) were not encrypted on encrypted flows, causing the receiver to fail decryption. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Make flow liveness timeout configurableDimitri Staessens2022-03-031-20/+46
| | | | | | | | | The qosspec_t now has a timeout value that sets the timeout value of the flow. Flows with a peer that has timed out will now return -EFLOWPEER on flow_read() or flow_write(). Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Add initial flow liveness monitoringDimitri Staessens2022-02-241-23/+159
| | | | | | | | | | | | | | | | | | This adds flow liveness monitoring for flows, with a fixed timeout of 120s. I will make it configurable at flow allocation later on (timeout needs to be communicated to the peer). If one peer dies, or doesn't call any IPC calls (flow_write/flow_read/fevent) it will stop sending keepalives and the other peer's read/writes will error on an -EFLOWDOWN after the timeout expires. Packets without a payload (0 length packets) are interpreted as keepalive packets for the flow. They can be sent from any application, but they will not trigger a message read at the receiver side (0 as a return value on flow_read indicates a previous partial read has completed at exactly the buffer size). Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Maintain a list of flows in flow_setDimitri Staessens2022-02-241-26/+99
| | | | | | | | | The flow_set will now keep a list of the flows in the set, this makes it more efficient to iterate over the flows. Extending the public API for fset_t with an iterator will also be useful. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Don't use pointer to set FRCT flagsDimitri Staessens2021-12-291-5/+4
| | | | | | | | | | | | | | | | | | The fccntl call FRCTSFLAGS was using a pointer to a flags so set flags, which should just be a regular uint16_t. For instance, the FRCTLINGER flags can now be turned off using fccntl(fd, FRCTSFLAGS, FRCTFRESCNTL | FRCTFRTX) leaving only resource control (flow control, FRCTFRESCNTL) and retransmission enabled. Note that retransmission (FRCTFRTX) can't be enabled or disabled on a live flow, it will be set on flow allocation. Updates the man page for fccntl to add these FRCT options. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Fix waiting for FRCT at deallocationDimitri Staessens2021-12-221-6/+6
| | | | | | | | | | This is a fix to wait for outstanding retransmissions when a flow is deallocated. Instead of waiting the full timeout, it will now wait in the same tic increments used within FRCT. Bit of a stopgap at the moment, FRCT and the flows are in need of a serious refactor. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Remove old rib_fini codeDimitri Staessens2021-12-061-3/+0
| | | | | | | | There was some leftover code in dev.c wrt to the process RIB that is not needed anymore. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Don't initialize process RIB for IPCPsDimitri Staessens2021-07-101-3/+5
| | | | | | | | | | | | | This will skip rib_init() at __init() for IPCPs (or at least, processes that have "ipcpd" in the executable name). The previous code tried to unmount the generic mount and then remount under the ipcp name, but it often failed because fuse_mount() is asynchronous and the mount was not up at the time of the unmount() call. Renaming the mount instead of unmounting failed for the same reason. This is a better fix for now. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Application RIB with FRCT statisticsDimitri Staessens2021-06-301-2/+18
| | | | | | | | | | Application flows can now be monitored from the RIB, exposing FRCT statistics (window edges, retransmission timeout, rtt estimate, etc). Application RIB requires user permissions to be able to access /dev/fuse. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib, ipcpd, irmd: Wrap pthread unlocks for cleanupDimitri Staessens2021-06-231-0/+1
| | | | | | | | | | | | This add an ouroboros/pthread.h header that wraps the pthread_..._unlock() functions for cleanup using pthread_cleanup_push() as this casting is not safe (and there were definitely bad casts in the code). The close() function is now also wrapped for cleanup in ouroboros/sockets.h. This allows enabling more compiler checks. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* build: Update email addressesDimitri Staessens2021-01-031-2/+2
| | | | | | | | The ugent email addresses are shut down, updated to Ouroboros mail addresses. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* build: Update copyright to 2021Dimitri Staessens2021-01-031-1/+1
| | | | | | | Happy New Year, Ouroboros! Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Fix flow_accept without opensslDimitri Staessens2020-12-121-4/+5
| | | | | | | | DH key creation was returning -ECRYPT if opennssl is not installed, instead of success (0). Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* ipcpd: Add congestion avoidance policiesDimitri Staessens2020-12-021-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds congestion avoidance policies to the unicast IPCP. The default policy is a multi-bit explicit congestion avoidance algorithm based on data-center TCP congestion avoidance (DCTCP) to relay information about the maximum queue depth that packets experienced to the receiver. There's also a "nop" policy to disable congestion avoidance for testing and benchmarking purposes. The (initial) API for congestion avoidance policies is: void * (* ctx_create)(void); void (* ctx_destroy)(void * ctx); These calls create / and or destroy a context for congestion control for a specific flow. Thread-safety of the context is the responsability of the flow allocator (operations on the ctx should be performed under a lock). ca_wnd_t (* ctx_update_snd)(void * ctx, size_t len); This is the sender call to update the context, and should be called for every packet that is sent on the flow. The len parameter in this API is the packet length, which allows calculating the bandwidth. It returns an opaque union type that is used for the call to check/wait if the congestion window is open or closed (and allowing to release locks before waiting). bool (* ctx_update_rcv)(void * ctx, size_t len, uint8_t ecn, uint16_t * ece); This is the call to update the flow congestion context on the receiver side. It should be called for every received packet. It gets the ecn value from the packet and its length, and returns the ECE (explicit congestion experienced) value to be sent to the sender in case of congestion. The boolean returned signals whether or not a congestion update needs to be sent. void (* ctx_update_ece)(void * ctx, uint16_t ece); This is the call for the sending side top update the context when it receives an ECE update from the receiver. void (* wnd_wait)(ca_wnd_t wnd); This is a (blocking) call that waits for the congestion window to clear. It should be stateless (to avoid waiting under locks). This may change later on if passing the context is needed for different algorithms. uint8_t (* calc_ecn)(int fd, size_t len); This is the call that intermediate IPCPs(routers) should use to update the ECN field on passing packets. The multi-bit ECN policy bases the value for the ECN field on the depth of the rbuff queue packets will be sent on. I created another call to grab the queue depth as fccntl is write-locking the application. We can further optimize this to avoid most locking on the rbuff. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Add Rendez-Vous mechanism for flow controlDimitri Staessens2020-10-111-2/+1
| | | | | | | | | | | | | This adds the rendez-vous mechanism to handle the case where the sending window is closed and window updates get lost. If the sending window is closed, the sender side will send an RDVS every DELT_RDV time (100ms), and give up after MAX_RDV time (1 second). Upon reception of a RDVS packet, a window update is sent immediately. We can make this much more configurable later on (build options for defaults, fccntl for runtime tuning). Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Block on closed flow control windowDimitri Staessens2020-10-111-13/+25
| | | | | | | | | | | If the sending window for flow control is closed, the sending application will now block until the window opens. Beware that until the rendez-vous mechanism is implemented, shutting down a server while the client is sending (with non-timed-out blocking write) will cause the client to hang indefinitely because its window will close. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Refactor flow_writeDimitri Staessens2020-10-111-20/+11
| | | | | | | Refactor flow_write cleanup. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Add compiler configuration for FRCPDimitri Staessens2020-10-111-2/+1
| | | | | | | | | | | | | This allows configuring some parameters for FRCP at compile time, such as default values for Delta-t and configuration of the timerwheel. The timerwheel will now reschedule when it fails to create a packet, instead of setting the flow down immediately. Some new things added are options to store packets for retransmission on the heap, and using non-blocking calls for retransmission. The defaults do not change the current behaviour. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Fix locking for FRCTDimitri Staessens2020-09-261-2/+4
| | | | | | | | Flows should be locked when moving the timerwheel. For frcti_snd, a rdlock is enough. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Complete retransmission logicDimitri Staessens2020-09-251-24/+109
| | | | | | | | | | | | | | | | | | | | | | | | | | | This completes the retransmission (automated repeat-request, ARQ) logic, sending (delayed) ACK messages when needed. On deallocation, flows will ACK try to retransmit any remaining unacknowledged messages (unless the FRCTFLINGER flag is turned off; this is on by default). Applications can safely shut down as soon as everything is ACK'd (i.e. the current Delta-t run is done). The activity timeout is now passed to the IPCP for it to sleep before completing deallocation (and releasing the flow_id). That should be moved to the IRMd in due time. The timerwheel is revised to be multi-level to reduce memory consumption. The resolution bumps by a factor of 1 << RXMQ_BUMP (16) and each level has RXMQ_SLOTS (1 << 8) slots. The lowest level has a resolution of (1 << RXMQ_RES) (20) ns, which is roughly a millisecond. Currently, 3 levels are defined, so the largest delay we can schedule at each level is: Level 0: 256ms Level 1: 4s Level 2: about a minute. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Allow pure acknowledgment packets in FRCTDimitri Staessens2020-06-061-21/+50
| | | | | | | | | | | | | | | | | | | | This adds the logic to send a pure acknowledgment packet without any data to send. This needed the event filter for the fqueue, as these non-data packets should not trigger application PKT events. The default timeout is now 10ms, until we have FRCP tuning as part of fccntl. Karn's algorithm seems to be very unstable with low (sub-ms) RTT estimates. Doubling RTO (every RTO) seems still too slow to prevent rtx storms when the measured rtt suddenly spikes several orders of magnitude. Just assuming the ACK'd packet is the last one transmitted seems to be a lot more stable. It can lead to temporary underestimation, but this is not a throughput-killer in FRCP. Changes most time units to nanoseconds for faster computation. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Refactor FRCTDimitri Staessens2020-05-041-33/+26
| | | | | | | | | | This is a small refactor of FRCT because I found some things a bit hard to read. I tried to refactor frcti_rcv to always queue the packet, but that causes unnecessarily retaking the lock when calling queued_pdu and thus returning idx is a tiny bit faster. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Create an rxmwheel per flowDimitri Staessens2020-05-021-11/+10
| | | | | | | | | The single retransmission wheel caused locking headaches as the calls for different flows could block on the same rxmwheel. This stabilizes the stack, but if the rdrbuff gets full there can now be big delays. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Return number of written bytes on flow_write0.17.0Dimitri Staessens2020-03-151-3/+2
| | | | | | | | | This is more in line with the write() system call and prepares for partial writes. Partial writes are disabled by default (and not yet implemented). Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Change return type of fevent to ssize_tDimitri Staessens2020-03-151-3/+3
| | | | | | | | The return type was still an int, but since it returns the number of events, it should be an ssize_t. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib, ipcpd: piggyback ECDHE on flow allocationDimitri Staessens2020-02-251-106/+146
| | | | | | | | | | | The initial implementation for the ECDHE key exchange was doing the key exchange after a flow was established. The public keys are now sent allowg on the flow allocation messages, so that an encrypted tunnel can be created within 1 RTT. The flow allocation steps had to be extended to pass the opaque data ('piggybacking'). Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* build: Update copyright to 20200.16.0Dimitri Staessens2020-01-021-1/+1
| | | | | Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Add check that flow_id is validSander Vrijders2019-10-061-0/+5
| | | | | | | | In fset_add, the flow_id was passed to the shm_flow_set without checking if it was actually valid. Signed-off-by: Sander Vrijders <sander@ouroboros.rocks> Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
* lib: Add per-message encryption with OpenSSLDimitri Staessens2019-08-031-15/+106
| | | | | | | | | | | | | | | | | | | This adds a per-message symmetric encryption using the OpenSSL library. At flow allocation, an Elliptic Curve Diffie-Hellman exchange is performed to derive a shared secret, which is then hashed using SHA3-256 to be used as a key for symmetric AES-256 encryption. Each message on an encrypted flow adds a small crypto header that includes a random 128-bit Initialization Vector (IV). If the server does not have OpenSSL enabled, the flow allocation will fail with an -ECRYPT error. Future optimizations are to piggyback the public keys on the flow allocation message, and to enable per-flow encryption that maintains the context of the encryption over multiple packets and doesn't require sending IVs. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* irmd, lib: Improve libgcrypt initDimitri Staessens2019-07-291-2/+7
| | | | | | | | | | The proper initialization of libgrypt requires a call to gcry_check_version. The library initialization should first run a check if the application (or some other library) hasn't already initialized libgcrypt before attempting to initialize libgcrypt. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* lib: Set independent size for rbuffDimitri Staessens2019-04-061-4/+11
| | | | | | | | | | This allows setting the size of the rbuffs in a system independently of the main packet buffer using SHM_RBUFF_SIZE. The benefit of setting a smaller rbuff size is that a single process can't fully occupy the main packet buffer. Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* build: Set specific compiler flags for SWIG target0.15.2Dimitri Staessens2019-03-211-2/+0
| | | | | | | | | | The compiler flags for the SWIG target were added to the global CMAKE_C_FLAGS used for the entire project. This sets the flags uniquely for the SWIG target. The eth has a similar case for the c99 flag. There was a lingering include in dev.c that was removed. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* ipcpd: Refactor create_r and flow_req_arrDimitri Staessens2019-03-041-6/+4
| | | | | | | | | | | The API calls for the IPCP to inform the IRMd of IPCP creation and incoming flow request had the pid_t in the call. This pid_t is removed and the getpid() call is now placed inside the function. Also refactors the cleanup for the main() functions of some of the lower IPCPs. Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks> Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
* build: Update copyright to 2019Dimitri Staessens2019-02-051-1/+1
| | | | | | | Updates the copyright notice in all sources to 2019. Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be> Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be>
* lib: Fix deallocating non-initialized np1 flowsDimitri Staessens2018-12-291-2/+11
| | | | | | | | This fixes the deallocation of non-initialized IPCP flows. These can occur when some operations are not implemented. Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be> Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be>
* include: Add a flow_join operation for broadcastDimitri Staessens2018-12-271-4/+22
| | | | | | | | | | | | This adds a new flow_join operaiton for broadcast, which is a much safer solution than overloading destination name semantics. The internal API now also has a different IPCP_FLOW_JOIN operation. The IRMd doesn't need to query broadcasts IPCPs for the name, it can just check if an IPCP with the layer name exists. The broadcast IPCP doesn't need to implement the query proxy call anymore. Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be> Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be>
* irmd: Manage shm_flow_set from IRMdDimitri Staessens2018-12-221-7/+7
| | | | | | | | | This moves the creation and destruction of shm_flow_set shared memory structures from the init to the IRMd. Now the management of all shared data objects is performed by the IRMd. Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be> Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be>
* lib: Fix reading tx queue length0.14.0Dimitri Staessens2018-12-071-1/+1
| | | | | | | The fccntl call was reading from the RX queue instead of the TX queue. Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be> Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be>
* lib: Revise du buff API towards a memory allocatorDimitri Staessens2018-10-261-25/+10
| | | | | | | | | This changes the API to the rdrbuff to treat it as a pool memory allocator. The head and tailspace to allocate in a buffer is now set system-wide instead of being passed as a parameter. Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be> Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be>
* ipcpd: Check flow id instead of assertDimitri Staessens2018-10-191-1/+4
| | | | | | | | | This will check if the flow id is valid instead of asserting. It avoids assertion failures in the IPCP if an application crashes and the IRMd deallocates the flow while the IPCP still has pending writes. Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be> Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be>
* Merge branch 'testing' into beSander Vrijders2018-10-111-1/+4
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| * lib: Initialize libgcrypt before useDimitri Staessens2018-10-111-1/+4
| | | | | | | | | | | | | | | | This initializes libgcrypt before use in the library. This fixes the "called in non-operational state" error when CRC checking is enabled. Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be> Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be>
* | Merge branch 'testing' into beDimitri Staessens2018-10-061-117/+152
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| * lib: Split error checking from FRCTDimitri Staessens2018-10-051-8/+55
| | | | | | | | | | | | | | | | This splits off the CRC from FRCT so it can be set independently. Ouroboros now allows raw flows with error checking. Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be> Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be>
| * lib: Rename port_id to flow_idDimitri Staessens2018-10-051-51/+51
| | | | | | | | | | | | | | Renames port_id to flow_id according to updated nomenclature. Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be> Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be>
| * ipcpd, lib, irmd, tools: Change SDU to packetSander Vrijders2018-10-051-7/+7
| | | | | | | | | | | | | | | | This will change SDU (Service Data Unit) to packet everywhere. SDU is OSI terminology, whereas packet is Ouroboros terminology. Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be> Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be>
| * lib: Pass qosspec at flow allocationDimitri Staessens2018-10-051-49/+38
| | | | | | | | | | | | | | | | | | | | | | | | The flow allocator now passes the full qos specification to the endpoint, instead of just a cube. This is a more flexible architecture, as it makes QoS cubes internal to the layers. Adds endianness transforms for the flow allocator protocol in the normal IPCP. Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be> Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be>
| * lib: Remove configuration from FRCTDimitri Staessens2018-09-271-6/+0
| | | | | | | | | | | | | | | | This removes configuration from the FRCT protocol to send it during flow allocation. Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be> Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be>
| * include: Remove _DEFAULT_SOURCE in endian.hDimitri Staessens2018-09-271-1/+6
| | | | | | | | | | | | | | | | This removes the _DEFAULT_SOURCE definition in the endian header as it should not be there. This avoids double and conflicting definitions. Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be> Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be>