diff options
Diffstat (limited to 'vag-bap-rx.c')
-rw-r--r-- | vag-bap-rx.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/vag-bap-rx.c b/vag-bap-rx.c new file mode 100644 index 0000000..2e6c0cd --- /dev/null +++ b/vag-bap-rx.c @@ -0,0 +1,171 @@ +#include <ctype.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include <linux/can.h> + +#include "vag-bap.h" + + +struct BAP_Frame* vag_bap_handle_can_frame(struct BAP_RXer *bap, struct can_frame *frame) +{ + struct BAP_Frame *bap_frame = NULL; + unsigned short header; + unsigned this_len; + + //printf("Received BAP frame from CAN ID %03x\n", frame->can_id); + + if (frame->can_dlc < 2) { + printf("Error: Frame too short\n"); + } + + if (frame->data[0] & 0x80) { + /* This is a multi-frame BAP message */ + int mfchannel = (frame->data[0] >> 4) & 0x3; + + if (!(frame->data[0] & 0x40)) { + /* Start frame */ + + unsigned short header; + unsigned this_len; + + if (frame->can_dlc < 4) { + printf("Error: Frame too short\n"); + } + + if (bap->mfchannel[mfchannel]) { + printf("bap_handle_can_frame: new start frame for open channel\n"); + } + bap->mfchannel[mfchannel] = NULL; + + bap_frame = vag_bap_frame_alloc(); + if (!bap_frame) { + printf("bap_handle_can_frame: Failed to allocate new frame\n"); + return NULL; + } + + bap_frame->is_multiframe = 1; + + header = (frame->data[2] << 8) | frame->data[3]; + bap_frame->opcode = (header >> 12) & 0x7; + bap_frame->node = (header >> 6) & 0x3F; + bap_frame->port = (header >> 0) & 0x3F; + + bap_frame->len = ((frame->data[0] & 0xF) << 8) | frame->data[1]; + + this_len = frame->can_dlc - 4; + + if (this_len > bap_frame->len) { + printf("bap_handle_can_frame: this_len > len\n"); + + free(bap_frame); + bap->mfchannel[mfchannel] = NULL; + + return NULL; + } + + memcpy(&bap_frame->data[0], &frame->data[frame->can_dlc - this_len], this_len); + bap->len_done[mfchannel] = this_len; + + if (bap->len_done[mfchannel] == bap_frame->len) { + /* Frame is complete, remove from buffer */ + bap->mfchannel[mfchannel] = NULL; + return bap_frame; + } else { + /* Frame is incomplete, don't emit it yet */ + bap->mfchannel[mfchannel] = bap_frame; + return NULL; + } + } else { + /* Continuation frame */ + + bap_frame = bap->mfchannel[mfchannel]; + + if (!bap_frame) { + printf("bap_handle_can_frame: continuation frame for unknown mf channel %d\n", + mfchannel); + } + + this_len = frame->can_dlc - 1; + + if ((bap->len_done[mfchannel] + this_len) > bap_frame->len) { + printf("bap_handle_can_frame: len_done + this_len > len\n"); + + free(bap_frame); + bap->mfchannel[mfchannel] = NULL; + + return NULL; + } + + memcpy(&bap_frame->data[bap->len_done[mfchannel]], + &frame->data[frame->can_dlc - this_len], + this_len); + bap->len_done[mfchannel] += this_len; + + if (bap->len_done[mfchannel] == bap_frame->len) { + /* Frame is complete, remove from buffer */ + bap->mfchannel[mfchannel] = NULL; + return bap_frame; + } else { + /* Frame is incomplete, don't emit it yet */ + return NULL; + } + } + } else { + /* Single-frame BAP message */ + + bap_frame = calloc(1, sizeof(struct BAP_Frame)); + if (!bap_frame) { + printf("bap_handle_can_frame: Failed to allocate new frame\n"); + return NULL; + } + + bap_frame->is_multiframe = 0; + + header = (frame->data[0] << 8) | frame->data[1]; + bap_frame->opcode = (header >> 12) & 0x7; + bap_frame->node = (header >> 6) & 0x3F; + bap_frame->port = (header >> 0) & 0x3F; + + this_len = frame->can_dlc - 2; + + bap_frame->len = this_len; + + memcpy(&bap_frame->data[0], &frame->data[frame->can_dlc - this_len], this_len); + + return bap_frame; + } +} + + + + + +struct BAP_RXer* vag_bap_rxer_alloc() +{ + struct BAP_RXer *bap; + + bap = calloc(1, sizeof(*bap)); + if (!bap) { + return NULL; + } + + return bap; +} + + + + +void vag_bap_rxer_free(struct BAP_RXer *bap) +{ + int i; + + for (i = 0; i < 8; i++) { + if (bap->mfchannel[i]) { + vag_bap_frame_free(bap->mfchannel[i]); + } + } + + free(bap); +} |