text: /*
   * Copyright (C) by Argonne National Laboratory
   *     See COPYRIGHT in top-level directory
   */
  
  #include "ad_lustre.h"
  #include "adio_extern.h"
  
  #define ADIOI_BUFFERED_WRITE                                            \
      {                                                                   \
          if (req_off >= writebuf_off + writebuf_len) {                   \
              if (writebuf_len) {                                         \
                  ADIO_WriteContig(fd, writebuf, writebuf_len, MPI_BYTE,  \
                                   ADIO_EXPLICIT_OFFSET, writebuf_off,    \
                                   &status1, error_code);                 \
                  if (!fd->atomicity && fd->hints->ds_write == ADIOI_HINT_DISABLE) \
                      ADIOI_UNLOCK(fd, writebuf_off, SEEK_SET, writebuf_len); \
                  if (*error_code != MPI_SUCCESS) {                       \
                      *error_code = MPIO_Err_create_code(*error_code,     \
                                                         MPIR_ERR_RECOVERABLE, \
                                                         myname,          \
                                                         __LINE__, MPI_ERR_IO, \
                                                         "**iowswc", 0);  \
                      ADIOI_Free(writebuf);                               \
                      return;                                             \
                  }                                                       \
              }                                                           \
              writebuf_off = req_off;                                     \
              /* stripe_size alignment */                                 \
              writebuf_len = (unsigned) MPL_MIN(end_offset - writebuf_off + 1, \
                                                (writebuf_off / stripe_size + 1) * \
                                                stripe_size - writebuf_off); \
              if (!fd->atomicity && fd->hints->ds_write == ADIOI_HINT_DISABLE) \
                  ADIOI_WRITE_LOCK(fd, writebuf_off, SEEK_SET, writebuf_len); \
              ADIO_ReadContig(fd, writebuf, writebuf_len, MPI_BYTE,       \
                              ADIO_EXPLICIT_OFFSET,                       \
                              writebuf_off, &status1, error_code);        \
              if (*error_code != MPI_SUCCESS) {                           \
                  *error_code = MPIO_Err_create_code(*error_code,         \
                                                     MPIR_ERR_RECOVERABLE, \
                                                     myname,              \
                                                     __LINE__, MPI_ERR_IO, \
                                                     "**iowsrc", 0);      \
                  ADIOI_Free(writebuf);                                   \
                  return;                                                 \
              }                                                           \
          }                                                               \
          write_sz = (unsigned) (MPL_MIN(req_len,                         \
                                         writebuf_off + writebuf_len - req_off)); \
          ADIOI_Assert((ADIO_Offset)write_sz ==                           \
                       MPL_MIN(req_len, writebuf_off + writebuf_len - req_off)); \
          memcpy(writebuf + req_off - writebuf_off, (char *)buf +userbuf_off, write_sz); \
          while (write_sz != req_len) {                                   \
              ADIO_WriteContig(fd, writebuf, writebuf_len, MPI_BYTE,      \
                               ADIO_EXPLICIT_OFFSET, writebuf_off, &status1, error_code); \
              if (!fd->atomicity && fd->hints->ds_write == ADIOI_HINT_DISABLE) \
                  ADIOI_UNLOCK(fd, writebuf_off, SEEK_SET, writebuf_len); \
              if (*error_code != MPI_SUCCESS) {                           \
                  *error_code = MPIO_Err_create_code(*error_code,         \
                                                     MPIR_ERR_RECOVERABLE, myname, \
                                                     __LINE__, MPI_ERR_IO, \
                                                     "**iowswc", 0);      \
                  ADIOI_Free(writebuf);                                   \
                  return;                                                 \
              }                                                           \
              req_len -= write_sz;                                        \
              userbuf_off += write_sz;                                    \
              writebuf_off += writebuf_len;                               \
              /* stripe_size alignment */                                 \
              writebuf_len = (unsigned) MPL_MIN(end_offset - writebuf_off + 1, \
                                                (writebuf_off / stripe_size + 1) * \
                                                stripe_size - writebuf_off); \
              if (!fd->atomicity && fd->hints->ds_write == ADIOI_HINT_DISABLE) \
                  ADIOI_WRITE_LOCK(fd, writebuf_off, SEEK_SET, writebuf_len); \
              ADIO_ReadContig(fd, writebuf, writebuf_len, MPI_BYTE,       \
                              ADIO_EXPLICIT_OFFSET,                       \
                              writebuf_off, &status1, error_code);        \
              if (*error_code != MPI_SUCCESS) {                           \
                  *error_code = MPIO_Err_create_code(*error_code,         \
                                                     MPIR_ERR_RECOVERABLE, myname, \
                                                     __LINE__, MPI_ERR_IO, \
                                                     "**iowsrc", 0);      \
                  ADIOI_Free(writebuf);                                   \
                  return;                                                 \
              }                                                           \
              write_sz = MPL_MIN(req_len, writebuf_len);                  \
              memcpy(writebuf, (char *)buf + userbuf_off, write_sz);      \
          }                                                               \
      }
  
  
  /* this macro is used when filetype is contig and buftype is not contig.
     it does not do a read-modify-write and does not lock*/
  #define ADIOI_BUFFERED_WRITE_WITHOUT_READ                               \
      {                                                                   \
          if (req_off >= writebuf_off + writebuf_len) {                   \
              ADIO_WriteContig(fd, writebuf, writebuf_len, MPI_BYTE,      \
                               ADIO_EXPLICIT_OFFSET, writebuf_off, &status1, \
                               error_code);                               \
              if (*error_code != MPI_SUCCESS) {                           \
                  *error_code = MPIO_Err_create_code(*error_code,         \
                                                     MPIR_ERR_RECOVERABLE, \
                                                     myname,              \
                                                     __LINE__, MPI_ERR_IO, \
                                                     "**iowswc", 0);      \
                  ADIOI_Free(writebuf);                                   \
                  return;                                                 \
              }                                                           \
              writebuf_off = req_off;                                     \
              /* stripe_size alignment */                                 \
              writebuf_len = (unsigned) MPL_MIN(end_offset - writebuf_off + 1, \
                                                (writebuf_off / stripe_size + 1) * \
                                                stripe_size - writebuf_off); \
          }                                                               \
          write_sz = (unsigned) MPL_MIN(req_len, writebuf_off + writebuf_len - req_off); \
          ADIOI_Assert((ADIO_Offset)write_sz == MPL_MIN(req_len, writebuf_off + writebuf_len - req_off)); \
          memcpy(writebuf + req_off - writebuf_off,                       \
                 (char *)buf + userbuf_off, write_sz);                    \
          while (write_sz != req_len) {                                   \
              ADIO_WriteContig(fd, writebuf, writebuf_len, MPI_BYTE,      \
                               ADIO_EXPLICIT_OFFSET, writebuf_off, &status1, error_code); \
              if (*error_code != MPI_SUCCESS) {                           \
                  *error_code = MPIO_Err_create_code(*error_code,         \
                                                     MPIR_ERR_RECOVERABLE, myname, \
                                                     __LINE__, MPI_ERR_IO, \
                                                     "**iowswc", 0);      \
                  ADIOI_Free(writebuf);                                   \
                  return;                                                 \
              }                                                           \
              req_len -= write_sz;                                        \
              userbuf_off += write_sz;                                    \
              writebuf_off += writebuf_len;                               \
              /* stripe_size alignment */                                 \
              writebuf_len = (unsigned) MPL_MIN(end_offset - writebuf_off + 1, \
                                                (writebuf_off / stripe_size + 1) * \
                                                stripe_size - writebuf_off); \
              write_sz = MPL_MIN(req_len, writebuf_len);                  \
              memcpy(writebuf, (char *)buf + userbuf_off, write_sz);      \
          }                                                               \
      }
  
  void ADIOI_LUSTRE_WriteStrided(ADIO_File fd, const void *buf, int count,
                                 MPI_Datatype datatype, int file_ptr_type,
                                 ADIO_Offset offset, ADIO_Status * status, int *error_code)
  {
      /* offset is in units of etype relative to the filetype. */
      ADIOI_Flatlist_node *flat_buf, *flat_file;
      ADIO_Offset i_offset, sum, size_in_filetype;
      int i, j, k, st_index = 0;
      int n_etypes_in_filetype;
      ADIO_Offset num, size, n_filetypes, etype_in_filetype, st_n_filetypes;
      ADIO_Offset abs_off_in_filetype = 0;
      MPI_Count filetype_size, etype_size, buftype_size;
      MPI_Aint filetype_extent, buftype_extent;
      int buf_count, buftype_is_contig, filetype_is_contig;
      ADIO_Offset userbuf_off;
      ADIO_Offset off, req_off, disp, end_offset = 0, writebuf_off, start_off;
      char *writebuf;
      unsigned bufsize, writebuf_len, write_sz;
      ADIO_Status status1;
      ADIO_Offset new_bwr_size, new_fwr_size, st_fwr_size, fwr_size = 0, bwr_size, req_len;
      int stripe_size;
      static char myname[] = "ADIOI_LUSTRE_WriteStrided";
  
      if (fd->hints->ds_write == ADIOI_HINT_DISABLE) {
          /* if user has disabled data sieving on writes, use naive
           * approach instead.
           */
          ADIOI_GEN_WriteStrided_naive(fd,
                                       buf,
                                       count, datatype, file_ptr_type, offset, status, error_code);
          return;
      }
  
      *error_code = MPI_SUCCESS;  /* changed below if error */
  
      ADIOI_Datatype_iscontig(datatype, &buftype_is_contig);
      ADIOI_Datatype_iscontig(fd->filetype, &filetype_is_contig);
  
      MPI_Type_size_x(fd->filetype, &filetype_size);
      if (!filetype_size) {
  #ifdef HAVE_STATUS_SET_BYTES
          MPIR_Status_set_bytes(status, datatype, 0);
  #endif
          *error_code = MPI_SUCCESS;
          return;
      }
  
      MPI_Type_extent(fd->filetype, &filetype_extent);
      MPI_Type_size_x(datatype, &buftype_size);
      MPI_Type_extent(datatype, &buftype_extent);
      etype_size = fd->etype_size;
  
      ADIOI_Assert((buftype_size * count) ==
                   ((ADIO_Offset) (unsigned) buftype_size * (ADIO_Offset) count));
      bufsize = buftype_size * count;
  
      /* get striping info */
      stripe_size = fd->hints->striping_unit;
  
      /* Different buftype to different filetype */
      if (!buftype_is_contig && filetype_is_contig) {
          /* noncontiguous in memory, contiguous in file. */
          flat_buf = ADIOI_Flatten_and_find(datatype);
  
          off = (file_ptr_type == ADIO_INDIVIDUAL) ? fd->fp_ind :
              fd->disp + (ADIO_Offset) etype_size *offset;
  
          start_off = off;
          end_offset = start_off + bufsize - 1;
          /* write stripe size buffer each time */
          writebuf = (char *) ADIOI_Malloc(MPL_MIN(bufsize, stripe_size));
          writebuf_off = 0;
          writebuf_len = 0;
  
          /* if atomicity is true or data sieving is not disable, lock the region
           * to be accessed */
          if (fd->atomicity || fd->hints->ds_write != ADIOI_HINT_DISABLE)
              ADIOI_WRITE_LOCK(fd, start_off, SEEK_SET, bufsize);
  
          for (j = 0; j < count; j++) {
              for (i = 0; i < flat_buf->count; i++) {
                  userbuf_off = (ADIO_Offset) j *(ADIO_Offset) buftype_extent + flat_buf->indices[i];
                  req_off = off;
                  req_len = flat_buf->blocklens[i];
                  ADIOI_BUFFERED_WRITE_WITHOUT_READ;
                  off += flat_buf->blocklens[i];
              }
          }
  
          /* write the buffer out finally */
          ADIO_WriteContig(fd, writebuf, writebuf_len, MPI_BYTE,
                           ADIO_EXPLICIT_OFFSET, writebuf_off, &status1, error_code);
  
          if (fd->atomicity || fd->hints->ds_write != ADIOI_HINT_DISABLE)
              ADIOI_UNLOCK(fd, start_off, SEEK_SET, bufsize);
          if (*error_code != MPI_SUCCESS) {
              ADIOI_Free(writebuf);
              return;
          }
          ADIOI_Free(writebuf);
          if (file_ptr_type == ADIO_INDIVIDUAL)
              fd->fp_ind = off;
      } else {
          /* noncontiguous in file */
          flat_file = ADIOI_Flatten_and_find(fd->filetype);
          disp = fd->disp;
  
          if (file_ptr_type == ADIO_INDIVIDUAL) {
              /* Wei-keng reworked type processing to be a bit more efficient */
              offset = fd->fp_ind - disp;
              n_filetypes = (offset - flat_file->indices[0]) / filetype_extent;
              offset -= (ADIO_Offset) n_filetypes *filetype_extent;
              /* now offset is local to this extent */
  
              /* find the block where offset is located, skip blocklens[i]==0 */
              for (i = 0; i < flat_file->count; i++) {
                  ADIO_Offset dist;
                  if (flat_file->blocklens[i] == 0)
                      continue;
                  dist = flat_file->indices[i] + flat_file->blocklens[i] - offset;
                  /* fwr_size is from offset to the end of block i */
                  if (dist == 0) {
                      i++;
                      offset = flat_file->indices[i];
                      fwr_size = flat_file->blocklens[i];
                      break;
                  }
                  if (dist > 0) {
                      fwr_size = dist;
                      break;
                  }
              }
              st_index = i;       /* starting index in flat_file->indices[] */
              offset += disp + (ADIO_Offset) n_filetypes *filetype_extent;
          } else {
              n_etypes_in_filetype = filetype_size / etype_size;
              n_filetypes = offset / n_etypes_in_filetype;
              etype_in_filetype = offset % n_etypes_in_filetype;
              size_in_filetype = etype_in_filetype * etype_size;
  
              sum = 0;
              for (i = 0; i < flat_file->count; i++) {
                  sum += flat_file->blocklens[i];
                  if (sum > size_in_filetype) {
                      st_index = i;
                      fwr_size = sum - size_in_filetype;
                      abs_off_in_filetype = flat_file->indices[i] +
                          size_in_filetype - (sum - flat_file->blocklens[i]);
                      break;
                  }
              }
  
              /* abs. offset in bytes in the file */
              offset = disp + (ADIO_Offset) n_filetypes *filetype_extent + abs_off_in_filetype;
          }
  
          start_off = offset;
  
          /* Wei-keng Liao:write request is within single flat_file
           * contig block*/
          /* this could happen, for example, with subarray types that are
           * actually fairly contiguous */
          if (buftype_is_contig && bufsize <= fwr_size) {
              req_off = start_off;
              req_len = bufsize;
              end_offset = start_off + bufsize - 1;
              writebuf = (char *) ADIOI_Malloc(MPL_MIN(bufsize, stripe_size));
              memset(writebuf, -1, MPL_MIN(bufsize, stripe_size));
              writebuf_off = 0;
              writebuf_len = 0;
              userbuf_off = 0;
              ADIOI_BUFFERED_WRITE_WITHOUT_READ;
              /* write the buffer out finally */
              if (fd->hints->ds_write != ADIOI_HINT_DISABLE)
                  ADIOI_WRITE_LOCK(fd, writebuf_off, SEEK_SET, writebuf_len);
              ADIO_WriteContig(fd, writebuf, writebuf_len, MPI_BYTE,
                               ADIO_EXPLICIT_OFFSET, writebuf_off, &status1, error_code);
              if (fd->hints->ds_write != ADIOI_HINT_DISABLE)
                  ADIOI_UNLOCK(fd, writebuf_off, SEEK_SET, writebuf_len);
  
              if (file_ptr_type == ADIO_INDIVIDUAL) {
                  /* update MPI-IO file pointer to point to the first byte
                   * that can be accessed in the fileview. */
                  fd->fp_ind = offset + bufsize;
                  if (bufsize == fwr_size) {
                      do {
                          st_index++;
                          if (st_index == flat_file->count) {
                              st_index = 0;
                              n_filetypes++;
                          }
                      } while (flat_file->blocklens[st_index] == 0);
                      fd->fp_ind = disp + flat_file->indices[st_index]
                      + (ADIO_Offset) n_filetypes *filetype_extent;
                  }
              }
              fd->fp_sys_posn = -1;       /* set it to null. */
  #ifdef HAVE_STATUS_SET_BYTES
              MPIR_Status_set_bytes(status, datatype, bufsize);
  #endif
              ADIOI_Free(writebuf);
              return;
          }
  
          /* Calculate end_offset, the last byte-offset that will be accessed.
           * e.g., if start_offset=0 and 100 bytes to be write, end_offset=99 */
  
          st_fwr_size = fwr_size;
          st_n_filetypes = n_filetypes;
          i_offset = 0;
          j = st_index;
          off = offset;
          fwr_size = MPL_MIN(st_fwr_size, bufsize);
          while (i_offset < bufsize) {
              i_offset += fwr_size;
              end_offset = off + fwr_size - 1;
  
              j = (j + 1) % flat_file->count;
              n_filetypes += (j == 0) ? 1 : 0;
              while (flat_file->blocklens[j] == 0) {
                  j = (j + 1) % flat_file->count;
                  n_filetypes += (j == 0) ? 1 : 0;
              }
  
              off = disp + flat_file->indices[j] + n_filetypes * (ADIO_Offset) filetype_extent;
              fwr_size = MPL_MIN(flat_file->blocklens[j], bufsize - i_offset);
          }
  
          /* if atomicity is true or data sieving is not disable, lock the region
           * to be accessed */
          if (fd->atomicity || fd->hints->ds_write != ADIOI_HINT_DISABLE)
              ADIOI_WRITE_LOCK(fd, start_off, SEEK_SET, end_offset - start_off + 1);
  
          writebuf_off = 0;
          writebuf_len = 0;
          writebuf = (char *) ADIOI_Malloc(stripe_size);
          memset(writebuf, -1, stripe_size);
  
          if (buftype_is_contig && !filetype_is_contig) {
  
  /* contiguous in memory, noncontiguous in file. should be the most
             common case. */
  
              i_offset = 0;
              j = st_index;
              off = offset;
              n_filetypes = st_n_filetypes;
              fwr_size = MPL_MIN(st_fwr_size, bufsize);
              while (i_offset < bufsize) {
                  if (fwr_size) {
                      /* TYPE_UB and TYPE_LB can result in
                       * fwr_size = 0. save system call in such cases */
                      /* lseek(fd->fd_sys, off, SEEK_SET);
                       * err = write(fd->fd_sys, ((char *) buf) + i_offset, fwr_size); */
  
                      req_off = off;
                      req_len = fwr_size;
                      userbuf_off = i_offset;
                      ADIOI_BUFFERED_WRITE;
                  }
                  i_offset += fwr_size;
  
                  if (off + fwr_size < disp + flat_file->indices[j] +
                      flat_file->blocklens[j] + n_filetypes * (ADIO_Offset) filetype_extent)
                      off += fwr_size;
                  /* did not reach end of contiguous block in filetype.
                   * no more I/O needed. off is incremented by fwr_size. */
                  else {
                      j = (j + 1) % flat_file->count;
                      n_filetypes += (j == 0) ? 1 : 0;
                      while (flat_file->blocklens[j] == 0) {
                          j = (j + 1) % flat_file->count;
                          n_filetypes += (j == 0) ? 1 : 0;
                      }
                      off = disp + flat_file->indices[j] +
                          n_filetypes * (ADIO_Offset) filetype_extent;
                      fwr_size = MPL_MIN(flat_file->blocklens[j], bufsize - i_offset);
                  }
              }
          } else {
  /* noncontiguous in memory as well as in file */
              flat_buf = ADIOI_Flatten_and_find(datatype);
  
              k = num = buf_count = 0;
              i_offset = flat_buf->indices[0];
              j = st_index;
              off = offset;
              n_filetypes = st_n_filetypes;
              fwr_size = st_fwr_size;
              bwr_size = flat_buf->blocklens[0];
  
              while (num < bufsize) {
                  size = MPL_MIN(fwr_size, bwr_size);
                  if (size) {
                      /* lseek(fd->fd_sys, off, SEEK_SET);
                       * err = write(fd->fd_sys, ((char *) buf) + i_offset, size); */
  
                      req_off = off;
                      req_len = size;
                      userbuf_off = i_offset;
                      ADIOI_BUFFERED_WRITE;
                  }
  
                  new_fwr_size = fwr_size;
                  new_bwr_size = bwr_size;
  
                  if (size == fwr_size) {
  /* reached end of contiguous block in file */
                      j = (j + 1) % flat_file->count;
                      n_filetypes += (j == 0) ? 1 : 0;
                      while (flat_file->blocklens[j] == 0) {
                          j = (j + 1) % flat_file->count;
                          n_filetypes += (j == 0) ? 1 : 0;
                      }
  
                      off = disp + flat_file->indices[j] +
                          n_filetypes * (ADIO_Offset) filetype_extent;
  
                      new_fwr_size = flat_file->blocklens[j];
                      if (size != bwr_size) {
                          i_offset += size;
                          new_bwr_size -= size;
                      }
                  }
  
                  if (size == bwr_size) {
  /* reached end of contiguous block in memory */
  
                      k = (k + 1) % flat_buf->count;
                      buf_count++;
                      i_offset = (ADIO_Offset) buftype_extent *
                          (ADIO_Offset) (buf_count / flat_buf->count) + flat_buf->indices[k];
                      new_bwr_size = flat_buf->blocklens[k];
                      if (size != fwr_size) {
                          off += size;
                          new_fwr_size -= size;
                      }
                  }
                  num += size;
                  fwr_size = new_fwr_size;
                  bwr_size = new_bwr_size;
              }
          }
  
          /* write the buffer out finally */
          if (writebuf_len) {
              ADIO_WriteContig(fd, writebuf, writebuf_len, MPI_BYTE,
                               ADIO_EXPLICIT_OFFSET, writebuf_off, &status1, error_code);
              if (!fd->atomicity && fd->hints->ds_write == ADIOI_HINT_DISABLE)
                  ADIOI_UNLOCK(fd, writebuf_off, SEEK_SET, writebuf_len);
              if (*error_code != MPI_SUCCESS)
                  return;
          }
          if (fd->atomicity || fd->hints->ds_write != ADIOI_HINT_DISABLE)
              ADIOI_UNLOCK(fd, start_off, SEEK_SET, end_offset - start_off + 1);
  
          ADIOI_Free(writebuf);
  
          if (file_ptr_type == ADIO_INDIVIDUAL)
              fd->fp_ind = off;
      }
  
      fd->fp_sys_posn = -1;       /* set it to null. */
  
  #ifdef HAVE_STATUS_SET_BYTES
      MPIR_Status_set_bytes(status, datatype, bufsize);
  /* This is a temporary way of filling in status. The right way is to
      keep track of how much data was actually written by ADIOI_BUFFERED_WRITE. */
  #endif
  
  }
  