Function reader_set_read_pos

libCacheSim/traceReader/reader.c:607–632

* jump to given position in the trace, such as 0.2, 0.5, 1.0, etc. * because certain functions require reader to be read sequentially, * this function should not be used in the middle of reading the trace */

 * this function should not be used in the middle of reading the trace
 */
void reader_set_read_pos(reader_t *const reader, double pos) {
  /* jason (202004): this may not work for CSV
   */
  if (pos > 1) pos = 1;

  size_t offset = (double)reader->file_size * pos;
  if (reader->trace_format == TXT_TRACE_FORMAT) {
    fseek(reader->file, offset, SEEK_SET);
    if (offset != 0 && offset != reader->file_size) {
      go_back_one_req(reader);
    }
    if (offset == reader->file_size) {
      char c;
      fseek(reader->file, -1, SEEK_CUR);
      int _v = fread(&c, 1, 1, reader->file);
      while (isspace(c)) {
        fseek(reader->file, -2, SEEK_CUR);
        _v = fread(&c, 1, 1, reader->file);
        DEBUG_ASSERT(_v == 1);
      }
    }
  } else {
    reader->mmap_offset = offset;
    reader->mmap_offset -= reader->mmap_offset % reader->item_size;
  }
}

void read_first_req(reader_t *reader, request_t *req) {
  uint64_t offset = reader->mmap_offset;