Pray, 'til I go blind

include/hexagram/can.h

@@ -12,6 +12,8 @@
 #define HEXAGRAM_CAN_DUMP_TYPE_UNKNOWN    0
 #define HEXAGRAM_CAN_DUMP_TYPE_SOCKETCAN 29
 
+#define HEXAGRAM_CAN_DUMP_TSRESOL_USEC    6
+
 typedef struct _hexagram_can_dump {
     char magic[4];
     uint32_t endian;
@@ -30,6 +32,9 @@ typedef struct _hexagram_can_stream hexagram_can_stream;
 
 hexagram_can_stream *hexagram_can_stream_open_fd(int fd);
 
+hexagram_can_stream *hexagram_can_stream_create(const char *file,
+                                                const char *iface);
+
 void hexagram_can_stream_destroy(hexagram_can_stream *stream);
 
 int hexagram_can_stream_read(hexagram_can_stream *stream,
@@ -37,4 +42,7 @@ int hexagram_can_stream_read(hexagram_can_stream *stream,
                              uint32_t *timestamp_lo,
                              struct can_frame *frame);
 
+int hexagram_can_stream_write(hexagram_can_stream *stream,
+                              struct can_frame *frame);
+
 #endif /* _HEXAGRAM_CAN_H */

src/can.c

@@ -1,6 +1,10 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <net/if.h>
 
 #include <hexagram/can.h>
 
@@ -54,6 +58,36 @@ error_malloc:
     return NULL;
 }
 
+hexagram_can_stream *hexagram_can_stream_create(const char *file,
+                                                const char *iface) {
+    int fd;
+    hexagram_can_dump header;
+
+    if ((fd = open(file, O_CREAT | O_WRONLY)) < 0) {
+        goto error_open;
+    }
+
+    memcpy(header.magic, HEXAGRAM_CAN_DUMP_MAGIC, strlen(HEXAGRAM_CAN_DUMP_MAGIC));
+
+    header.endian  = HEXAGRAM_CAN_DUMP_ENDIAN;
+    header.type    = PF_CAN;
+    header.tsresol = HEXAGRAM_CAN_DUMP_TSRESOL_USEC;
+
+    strncpy(header.iface, iface, sizeof(header.iface));
+
+    if (write(fd, &header, sizeof(header)) < 0) {
+        goto error_write;
+    }
+
+    return hexagram_can_stream_open_fd(fd);
+
+error_write:
+    close(fd);
+
+error_open:
+    return NULL;
+}
+
 void hexagram_can_stream_destroy(hexagram_can_stream *stream) {
     memset(stream, '\0', sizeof(*stream));
 
@@ -83,3 +117,23 @@ int hexagram_can_stream_read(hexagram_can_stream *stream,
 error_io:
     return -1;
 }
+
+int hexagram_can_stream_write(hexagram_can_stream *stream,
+                              struct can_frame *frame) {
+    hexagram_can_frame data;
+    struct timeval now;
+
+    if (gettimeofday(&now, NULL) < 0) {
+        goto error_gettimeofday;
+    }
+
+    data.timestamp_hi = now.tv_usec & 0xffffffff00000000 >> 32;
+    data.timestamp_lo = now.tv_usec & 0x00000000ffffffff;
+
+    memcpy(&data.frame, frame, sizeof(data.frame));
+
+    return write(stream->fd, &data, sizeof(data));
+
+error_gettimeofday:
+    return -1;
+}