interp_read.cc

Source code for an Numeric Cmputer

   1. The first character read is not f:
      NCE_BUG_FUNCTION_SHOULD_NOT_HAVE_BEEN_CALLED
   2. An f_number has already been inserted in the block:
      NCE_MULTIPLE_F_WORDS_ON_ONE_LINE
   3. The f_number is negative: NCE_NEGATIVE_F_WORD_USED

Side effects:
   counter is reset to point to the first character following the f_number.
   The f_number is inserted in block.

Called by: read_one_item

When this function is called, counter is pointing at an item on the
line that starts with the character 'f'. The function reads characters
which tell how to set the f_number, up to the start of the next item
or the end of the line. This information is inserted in the block.

The value may be a real number or something that evaluates to a real
number, so read_real_value is used to read it. Parameters may be
involved, so the parameters argument is required. The value is always
a feed rate.

*/

int Interp::read_f(char *line,   //!< string: line of RS274 code being processed   
                  int *counter, //!< pointer to a counter for position on the line
                  block_pointer block,  //!< pointer to a block being filled from the line
                  double *parameters)   //!< array of system parameters                   
{
  static char name[] = "read_f";
  double value;
  int status;

  CHK((line[*counter] != 'f'), NCE_BUG_FUNCTION_SHOULD_NOT_HAVE_BEEN_CALLED);
  *counter = (*counter + 1);
  CHK((block->f_number > -1.0), NCE_MULTIPLE_F_WORDS_ON_ONE_LINE);
  CHP(read_real_value(line, counter, &value, parameters));
  CHK((value < 0.0), NCE_NEGATIVE_F_WORD_USED);
  block->f_number = value;
  return INTERP_OK;
}

/****************************************************************************/

/*! read_g

Returned Value: int
   If read_real_value returns an error code, this returns that code.
   If any of the following errors occur, this returns the error code shown.
   Otherwise, it returns INTERP_OK.
   1. The first character read is not g:
      NCE_BUG_FUNCTION_SHOULD_NOT_HAVE_BEEN_CALLED
   2. The value is negative: NCE_NEGATIVE_G_CODE_USED
   3. The value differs from a number ending in an even tenth by more
      than 0.0001: NCE_G_CODE_OUT_OF_RANGE
   4. The value is greater than 99.9: NCE_G_CODE_OUT_OF_RANGE
   5. The value is not the number of a valid g code: NCE_UNKNOWN_G_CODE_USED
   6. Another g code from the same modal group has already been
      inserted in the block: NCE_TWO_G_CODES_USED_FROM_SAME_MODAL_GROUP

Side effects:
   counter is reset to the character following the end of the g_code.
   A g code is inserted as the value of the appropriate mode in the
   g_modes array in the block.
   The g code counter in the block is increased by 1.

Called by: read_one_item

When this function is called, counter is pointing at an item on the
line that starts with the character 'g', indicating a g_code.  The
function reads characters which tell how to set the g_code.

The RS274/NGC manual [NCMS, page 51] allows g_codes to be represented
by expressions and provide [NCMS, 71 - 73] that a g_code must evaluate
to to a number of the form XX.X (59.1, for example). The manual does not
say how close an expression must come to one of the allowed values for
it to be legitimate. Is 59.099999 allowed to mean 59.1, for example?
In the interpreter, we adopt the convention that the evaluated number
for the g_code must be within 0.0001 of a value of the form XX.X

To simplify the handling of g_codes, we convert them to integers by
multiplying by 10 and rounding down or up if within 0.001 of an
integer. Other functions that deal with g_codes handle them
symbolically, however. The symbols are defined in rs274NGC.hh
where G_1 is 10, G_83 is 830, etc.

This allows any number of g_codes on one line, provided that no two
are in the same modal group.

This allows G80 on the same line as one other g_code with the same
mode. If this happens, the G80 is simply ignored.

*/

int Interp::read_g(char *line,   //!< string: line of RS274/NGC code being processed
                  int *counter, //!< pointer to a counter for position on the line 
                  block_pointer block,  //!< pointer to a block being filled from the line 
                  double *parameters)   //!< array of system parameters                    
{
  static char name[] = "read_g";
  double value_read;
  int value;
  int mode;
  int status;

  CHK((line[*counter] != 'g'), NCE_BUG_FUNCTION_SHOULD_NOT_HAVE_BEEN_CALLED);
  *counter = (*counter + 1);
  CHP(read_real_value(line, counter, &value_read, parameters));
  value_read = (10.0 * value_read);
  value = (int) floor(value_read);

  if ((value_read - value) > 0.999)
    value = (int) ceil(value_read);
  else if ((value_read - value) > 0.001)
    ERM(NCE_G_CODE_OUT_OF_RANGE);

  CHK((value > 999), NCE_G_CODE_OUT_OF_RANGE);
  CHK((value < 0), NCE_NEGATIVE_G_CODE_USED);
  mode = _gees[value];
  CHK((mode == -1), NCE_UNKNOWN_G_CODE_USED);
  if ((value == G_80) && (block->g_modes[mode] != -1));
  else {
    if (block->g_modes[mode] == G_80);
    else {
      CHK((block->g_modes[mode] != -1),
          NCE_TWO_G_CODES_USED_FROM_SAME_MODAL_GROUP);
    }
    block->g_modes[mode] = value;
  }
  return INTERP_OK;
}

/****************************************************************************/

/*! read_h

Returned Value: int
   If read_integer_value returns an error code, this returns that code.
   If any of the following errors occur, this returns the error code shown.
   Otherwise, it returns INTERP_OK.
   1. The first character read is not h:
      NCE_BUG_FUNCTION_SHOULD_NOT_HAVE_BEEN_CALLED
   2. An h_number has already been inserted in the block:
      NCE_MULTIPLE_H_WORDS_ON_ONE_LINE
   3. The value is negative: NCE_NEGATIVE_H_WORD_TOOL_LENGTH_OFFSET_INDEX_USED
   4. The value is greater than _setup.tool_max:
      NCE_TOOL_LENGTH_OFFSET_INDEX_TOO_BIG

Side effects:
   counter is reset to the character following the h_number.
   An h_number is inserted in the block.

Called by: read_one_item

When this function is called, counter is pointing at an item on the
line that starts with the character 'h', indicating a tool length
offset index.  The function reads characters which give the (integer)
value of the tool length offset index (not the actual distance of the
offset).

*/

int Interp::read_h(char *line,   //!< string: line of RS274/NGC code being processed
                  int *counter, //!< pointer to a counter for position on the line 
                  block_pointer block,  //!< pointer to a block being filled from the line 
                  double *parameters)   //!< array of system parameters                    
{
  static char name[] = "read_h";
  int value;
  int status;

  CHK((line[*counter] != 'h'), NCE_BUG_FUNCTION_SHOULD_NOT_HAVE_BEEN_CALLED);
  *counter = (*counter + 1);
  CHK((block->h_number > -1), NCE_MULTIPLE_H_WORDS_ON_ONE_LINE);
  CHP(read_integer_value(line, counter, &value, parameters));
  CHK((value < 0), NCE_NEGATIVE_H_WORD_TOOL_LENGTH_OFFSET_INDEX_USED);
  CHK((value > _setup.tool_max), NCE_TOOL_LENGTH_OFFSET_INDEX_TOO_BIG);
  block->h_number = value;
  return INTERP_OK;
}

/****************************************************************************/

/*! read_i

Returned Value: int
   If read_real_value returns an error code, this returns that code.
   If any of the following errors occur, this returns the error code shown.
   Otherwise, it returns INTERP_OK.
   1. The first character read is not i:
      NCE_BUG_FUNCTION_SHOULD_NOT_HAVE_BEEN_CALLED
   2. An i_coordinate has already been inserted in the block:
      NCE_MULTIPLE_I_WORDS_ON_ONE_LINE

Side effects:
   counter is reset.
   The i_flag in the block is turned on.
   An i_coordinate setting is inserted in the block.

Called by: read_one_item

When this function is called, counter is pointing at an item on the
line that starts with the character 'i', indicating a i_coordinate
setting. The function reads characters which tell how to set the
coordinate, up to the start of the next item or the end of the line.
This information is inserted in the block. The counter is then set to
point to the character following.

The value may be a real number or something that evaluates to a
real number, so read_real_value is used to read it. Parameters
may be involved.

*/

int Interp::read_i(char *line,   //!< string: line of RS274 code being processed    
                  int *counter, //!< pointer to a counter for position on the line 
                  block_pointer block,  //!< pointer to a block being filled from the line 
                  double *parameters)   //!< array of system parameters                    
{
  static char name[] = "read_i";
  double value;
  int status;

  CHK((line[*counter] != 'i'), NCE_BUG_FUNCTION_SHOULD_NOT_HAVE_BEEN_CALLED);
  *counter = (*counter + 1);
  CHK((block->i_flag != OFF), NCE_MULTIPLE_I_WORDS_ON_ONE_LINE);
  CHP(read_real_value(line, counter, &value, parameters));
  block->i_flag = ON;
  block->i_number = value;
  return INTERP_OK;
}

/****************************************************************************/

/*! read_integer_unsigned

Returned Value: int
   If any of the following errors occur, this returns the error shown.
   Otherwise, INTERP_OK is returned.
   1. The first character is not a digit: NCE_BAD_FORMAT_UNSIGNED_INTEGER
   2. sscanf fails: NCE_SSCANF_FAILED

Side effects:
   The number read from the line is put into what integer_ptr points at.

Called by: read_line_number

This reads an explicit unsigned (positive) integer from a string,
starting from the position given by *counter. It expects to find one
or more digits. Any character other than a digit terminates reading
the integer. Note that if the first character is a sign (+ or -),
an error will be reported (since a sign is not a digit).

*/

int Interp::read_integer_unsigned(char *line,    //!< string: line of RS274 code being processed   
                                 int *counter,  //!< pointer to a counter for position on the line
                                 int *integer_ptr)      //!< pointer to the value being read              
{
  static char name[] = "read_integer_unsigned";
  int n;
  char c;

  for (n = *counter;; n++) {
    c = line[n];
    if ((c < 48) || (c > 57))
      break;
  }
  CHK((n == *counter), NCE_BAD_FORMAT_UNSIGNED_INTEGER);
  if (sscanf(line + *counter, "%d", integer_ptr) == 0)
    ERM(NCE_SSCANF_FAILED);
  *counter = n;
  return INTERP_OK;
}

/****************************************************************************/

/*! read_integer_value

Returned Value: int
   If read_real_value returns an error code, this returns that code.
   If any of the following errors occur, this returns the error code shown.
   Otherwise, it returns INTERP_OK.
   1. The returned value is not close to an integer:
      NCE_NON_INTEGER_VALUE_FOR_INTEGER

Side effects:
   The number read from the line is put into what integer_ptr points at.

Called by:
   read_d
   read_l
   read_h
   read_m
   read_parameter
   read_parameter_setting
   read_t

This reads an integer (positive, negative or zero) from a string,
starting from the position given by *counter. The value being
read may be written with a decimal point or it may be an expression
involving non-integers, as long as the result comes out within 0.0001
of an integer.

This proceeds by calling read_real_value and checking that it is
close to an integer, then returning the integer it is close to.

*/

int Interp::read_integer_value(char *line,       //!< string: line of RS274/NGC code being processed
                              int *counter,     //!< pointer to a counter for position on the line 
                              int *integer_ptr, //!< pointer to the value being read               
                              double *parameters)       //!< array of system parameters                    
{
  static char name[] = "read_integer_value";
  double float_value;
  int status;

  CHP(read_real_value(line, counter, &float_value, parameters));
  *integer_ptr = (int) floor(float_value);
  if ((float_value - *integer_ptr) > 0.9999) {
    *integer_ptr = (int) ceil(float_value);
  } else if ((float_value - *integer_ptr) > 0.0001)
    ERM(NCE_NON_INTEGER_VALUE_FOR_INTEGER);
  return INTERP_OK;
}

/****************************************************************************/

/*! read_items

Returned Value: int
   If read_line_number or read_one_item returns an error code,
   this returns that code.
   Otherwise, it returns INTERP_OK.

Side effects:
   One line of RS274 code is read and data inserted into a block.
   The counter which is passed around among the readers is initialized.
   System parameters may be reset.

Called by: parse_line

*/

int Interp::read_items(block_pointer block,      //!< pointer to a block being filled from the line 
                      char *line,       //!< string: line of RS274/NGC code being processed
                      double *parameters)       //!< array of system parameters                    
{
  static char name[] = "read_items";
  int counter;
  int length;
  int status;

  length = strlen(line);
  counter = 0;

  if (line[counter] == '/')     /* skip the slash character if first */
    counter++;

  if (line[counter] == 'o')
 /* Handle 'o' explicitly here. Default is
    to read letters via pointer calls to related
    reader functions. 'o' control lines have their
    own commands and command handlers. */
    {
      CHP(read_o(line, &counter, block, parameters));
      return INTERP_OK;
    }