/* Prototype stuff for parsing Level-II data */
+/*
+ * TODO: ARGG, the packet sizses are all wrong..
+ * Check sizes of decompressed bzip files
+ * Split things back up to seperate files
+ * The second bzip contains different size packets?
+ */
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <error.h>
-#include <arpa/inet.h>
+#include <glib.h>
+#include <bzlib.h>
+#include "level2.h"
-struct packet {
- short junk1[6];
- unsigned short size;
- unsigned char id, type;
- unsigned short seq, gen_date;
- unsigned int gen_time;
- unsigned short num_seg, seg;
- unsigned int coll_time;
- unsigned short coll_date, range, angle, radial, rad_status, elev_angle;
- unsigned short elev_num;
- short first_refl, first_dopp;
- unsigned short refl_size, dopp_size;
- unsigned short num_refl_gate, num_dopp_gate, sector;
- float gain;
- unsigned short refl_ptr, vel_ptr, spec_ptr, dopp_res, pattern;
- short junk2[4];
- unsigned short refl_ptr_rda, vel_ptr_rda, spec_ptr_rda, nyquist, atten;
- short thresh;
- short junk3[17];
- unsigned char data[2304];
- float dbz[460];
-};
+level2_packet_t **level2_split_packets(char *data, int *num_packets, int data_size)
+{
+ int packet_i = 0;
+ level2_packet_t *packet = (level2_packet_t *)data;
+ int max_packets = 128;
+ level2_packet_t **packets = malloc(sizeof(level2_packet_t *)*max_packets);
+ while ((void *)packet < (void *)(data+data_size)) {
+ /* Increase packets size if necessasairy */
+ if (packet_i >= max_packets) {
+ max_packets *= 2;
+ packets = realloc(packets, sizeof(level2_packet_t *)*max_packets);
+ }
-typedef struct {
- /* 24 bytes */
- char version[4];
- char unknown0[16];
- char station[4];
-} __attribute__ ((packed)) header_t;
+ /* Fix byte order for packet */
+ packet->size = g_ntohs(packet->size);
+ packet->seq = g_ntohs(packet->seq);
+ // TODO: Convert the rest of the bytes
-int main(int argc, char **argv)
-{
- if (argc < 2) {
- printf("usage: %s <level2-data>\n", argv[0]);
- return 0;
+ /* Save packet location */
+ packets[packet_i] = packet;
+
+ /* Increment packet and packet_i */
+ // new = old + CTM + 2*size + fcs
+ //packet = (level2_packet_t *)( ((char *)packet) + 12 + 2*packet->size + 4 );
+ packet++;
+ packet_i++;
}
+ packets = realloc(packets, sizeof(level2_packet_t *)*packet_i);
+ *num_packets = packet_i;
+ return packets;
+}
+level2_packet_t *level2_decompress(char *raw_data, int *num_packets)
+{
/* Read header */
- FILE *fd = fopen(argv[1], "r");
+ FILE *fd = fopen(raw_data, "r");
if (fd == NULL)
- error(1, errno, "Error opening files `%s'", argv[1]);
- header_t header;
- if (1 != fread(&header, sizeof(header_t), 1, fd))
+ error(1, errno, "Error opening files `%s'", raw_data);
+ level2_header_t header;
+ if (1 != fread(&header, sizeof(level2_header_t), 1, fd))
error(1, errno, "Error reading header");
- /* Cut up the bzips */
- int file_num = 0;
- char filename[16];
- char *buf = NULL;
- FILE *outfile = NULL;
- unsigned int size = 0;
-
- while ((int)size >= 0) {
- if (1 != fread(&size, 4, 1, fd))
- break; //error(1, errno, "Error reading size, pos=%x", (unsigned int)ftell(fd));
- size = ntohl(size);
+ /* Decompress the bzips
+ * store the entire sequence starting at data
+ * cur_data is for each individual bzip and is the last chunk of data */
+ char *data = NULL;
+ int data_size = 0; // size of previously decmpressed data
+ char *bz2 = NULL; // temp buf for bzipped data
+ unsigned int _bz2_size = 0;
+ while ((int)_bz2_size >= 0) {
+ if (1 != fread(&_bz2_size, 4, 1, fd))
+ break; //error(1, errno, "Error reading _bz2_size, pos=%x", (unsigned int)ftell(fd));
+ _bz2_size = g_ntohl(_bz2_size);
+ int bz2_size = abs(_bz2_size);
/* Read data */
- ;
- if (NULL == (buf = (char *)realloc(buf, size)))
- error(1, errno, "cannot allocate `%d' bytes for buffer", size);
- if (size != fread(buf, 1, size, fd))
+ if (NULL == (bz2 = (char *)realloc(bz2, bz2_size)))
+ error(1, errno, "cannot allocate `%d' bytes for buffer", bz2_size);
+ if (bz2_size != fread(bz2, 1, bz2_size, fd))
error(1, errno, "error reading from input file");
- /* Decmopress data */
- //char *block = (char *)malloc(8192), *oblock = (char *)malloc(262144);
- //error = BZ2_bzBuffToBuffDecompress(oblock, &olength, block, length, 0, 0);
+ /* Decompress on individual bzip to the end of the sequence */
+ unsigned int cur_data_size = 1<<17;
+ int status = BZ_OUTBUFF_FULL;
+ while (status == BZ_OUTBUFF_FULL) {
+ cur_data_size *= 2;
+ data = realloc(data, data_size + cur_data_size);
+ status = BZ2_bzBuffToBuffDecompress(data + data_size, &cur_data_size, bz2, bz2_size, 0, 0);
+ }
+ if (status != BZ_OK)
+ error(1, 1, "Error decompressing data");
+ data_size += cur_data_size; // Add current chunk to decompressed data
- /* Write data */
- snprintf(filename, 16, "%d.bz2", file_num);
- outfile = fopen(filename, "w+");
- fwrite(buf, 1, size, outfile);
- fclose(outfile);
+ /* Debug */
+ printf("data_size = %d, cur_data_size = %d\n", data_size, cur_data_size);
+ }
+ data = realloc(data, data_size); // free unused space at the end
+
+ return (level2_packet_t *)data;
+ //return level2_split_packets(data, num_packets, data_size);
+}
+
+int main(int argc, char **argv)
+{
+ if (argc < 2) {
+ printf("usage: %s <level2-data>\n", argv[0]);
+ return 0;
+ }
- //fprintf(stderr, "wrote `%d' bytes to file `%s'\n", size, filename);
+ int num_packets;
+ level2_packet_t *packets = level2_decompress(argv[1], &num_packets);
+ printf("read %d packets\n", num_packets);
+
+ //FILE *output = fopen("output.dat", "w+");
+ //fwrite(packets[i], 1, 18470816, output);
+ //fclose(output);
- /* iterate */
- file_num++;
+ FILE *output = fopen("output.dat", "w+");
+ int i;
+ for (i = 0; i < 10000; i++) {
+ printf("packet: size=%x, seq=%d\n", g_ntohs(packets[i].size), g_ntohs(packets[i].seq));
+ fwrite("################", 1, 16, output);
+ fwrite(packets+i, 1, sizeof(level2_packet_t), output);
}
+ fclose(output);
return 0;
}
projects / aweather / blobdiff