Function strextract_ioreader

example/plugins/c-api/thread_pool/psi.cc:270–335

------------------------------------------------------------------------- strextract_ioreader Extract a string from an iobuffer. Start reading at position offset in iobuffer and extract until the string end_pattern is found. Input: reader reader on a iobuffer offset position to start reading end_pattern the termination string (nul terminated) Output: buffer

    STR_FAIL    if extraction failed
  -------------------------------------------------------------------------*/
static int
strextract_ioreader(TSIOBufferReader reader, int offset, const char *end_pattern, char *buffer, int *buflen)
{
  int             buf_idx       = 0;
  int             p_idx         = 0;
  int             nbytes_so_far = 0;
  int             plen          = strlen(end_pattern);
  const char     *ptr;
  TSIOBufferBlock block = TSIOBufferReaderStart(reader);

  if (plen <= 0) {
    return STR_FAIL;
  }

  /* Now start extraction */
  while ((block != nullptr) && (p_idx < plen) && (buf_idx < PSI_FILENAME_MAX_SIZE)) {
    int64_t     blocklen;
    const char *blockptr = TSIOBufferBlockReadStart(block, reader, &blocklen);

    for (ptr = blockptr; ptr < blockptr + blocklen; ptr++, nbytes_so_far++) {
      if (nbytes_so_far >= offset) {
        /* Add a new character to the filename */
        buffer[buf_idx++] = *ptr;

        /* If we have reach the end of the filename, we're done */
        if (end_pattern[p_idx] == *ptr) {
          p_idx++;
          if (p_idx == plen) {
            break;
          }
        } else {
          p_idx = 0;
        }

        /* The filename is too long, something is fishy... let's abort extraction */
        if (buf_idx >= PSI_FILENAME_MAX_SIZE) {
          break;
        }
      }
    }

    block = TSIOBufferBlockNext(block);
  }

  /* Error, could not read end of filename */
  if (buf_idx >= PSI_FILENAME_MAX_SIZE) {
    Dbg(dbg_ctl, "strextract: filename too long");
    *buflen = 0;
    return STR_FAIL;
  }

  /* Full Match */
  if (p_idx == plen) {
    /* Nul terminate the filename, remove the end_pattern copied into the buffer */
    *buflen         = buf_idx - plen;
    buffer[*buflen] = '\0';
    Dbg(dbg_ctl, "strextract: filename = |%s|", buffer);
    return STR_SUCCESS;