1 /* Copyright (C) 2002-2003 Free Software Foundation, Inc.
2 Contributed by Andy Vaught
4 This file is part of the GNU Fortran 95 runtime library (libgfortran).
6 Libgfortran is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 Libgfortran is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with Libgfortran; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
28 #include "libgfortran.h"
31 /* read.c -- Deal with formatted reads */
33 /* set_integer()-- All of the integer assignments come here to
34 * actually place the value into memory. */
37 set_integer (void *dest
, int64_t value
, int length
)
43 *((int64_t *) dest
) = value
;
46 *((int32_t *) dest
) = value
;
49 *((int16_t *) dest
) = value
;
52 *((int8_t *) dest
) = value
;
55 internal_error ("Bad integer kind");
60 /* max_value()-- Given a length (kind), return the maximum signed or
64 max_value (int length
, int signed_flag
)
71 value
= signed_flag
? 0x7fffffffffffffff : 0xffffffffffffffff;
74 value
= signed_flag
? 0x7fffffff : 0xffffffff;
77 value
= signed_flag
? 0x7fff : 0xffff;
80 value
= signed_flag
? 0x7f : 0xff;
83 internal_error ("Bad integer kind");
90 /* convert_real()-- Convert a character representation of a floating
91 * point number to the machine number. Returns nonzero if there is a
92 * range problem during conversion. TODO: handle not-a-numbers and
96 convert_real (void *dest
, const char *buffer
, int length
)
105 #if defined(HAVE_STRTOF)
106 strtof (buffer
, NULL
);
108 (float) strtod (buffer
, NULL
);
112 *((double *) dest
) = strtod (buffer
, NULL
);
115 internal_error ("Unsupported real kind during IO");
120 generate_error (ERROR_READ_VALUE
,
121 "Range error during floating point read");
129 /* read_l()-- Read a logical value */
132 read_l (fnode
* f
, char *dest
, int length
)
160 set_integer (dest
, 1, length
);
164 set_integer (dest
, 0, length
);
168 generate_error (ERROR_READ_VALUE
, "Bad value on logical read");
174 /* read_a()-- Read a character record. This one is pretty easy. */
177 read_a (fnode
* f
, char *p
, int length
)
183 if (w
== -1) /* '(A)' edit descriptor */
186 source
= read_block (&w
);
190 source
+= (w
- length
);
192 m
= (w
> length
) ? length
: w
;
193 memcpy (p
, source
, m
);
197 memset (p
+ m
, ' ', n
);
201 /* eat_leading_spaces()-- Given a character pointer and a width,
202 * ignore the leading spaces. */
205 eat_leading_spaces (int *width
, char *p
)
210 if (*width
== 0 || *p
!= ' ')
222 next_char (char **p
, int *w
)
237 if (g
.blank_status
== BLANK_ZERO
)
240 /* At this point, the rest of the field has to be trailing blanks */
254 /* read_decimal()-- Read a decimal integer value. The values here are
258 read_decimal (fnode
* f
, char *dest
, int length
)
260 unsigned value
, maxv
, maxv_10
;
269 p
= eat_leading_spaces (&w
, p
);
272 set_integer (dest
, 0, length
);
276 maxv
= max_value (length
, 1);
298 /* At this point we have a digit-string */
303 c
= next_char (&p
, &w
);
307 if (c
< '0' || c
> '9')
316 if (value
> maxv
- c
)
321 v
= (signed int) value
;
325 set_integer (dest
, v
, length
);
329 generate_error (ERROR_READ_VALUE
, "Bad value during integer read");
333 generate_error (ERROR_READ_OVERFLOW
,
334 "Value overflowed during integer read");
339 /* read_radix()-- This function reads values for non-decimal radixes.
340 * The difference here is that we treat the values here as unsigned
341 * values for the purposes of overflow. If minus sign is present and
342 * the top bit is set, the value will be incorrect. */
345 read_radix (fnode
* f
, char *dest
, int length
, int radix
)
347 unsigned value
, maxv
, maxv_r
;
356 p
= eat_leading_spaces (&w
, p
);
359 set_integer (dest
, 0, length
);
363 maxv
= max_value (length
, 0);
364 maxv_r
= maxv
/ radix
;
385 /* At this point we have a digit-string */
390 c
= next_char (&p
, &w
);
397 if (c
< '0' || c
> '1')
402 if (c
< '0' || c
> '7')
427 c
= c
- 'a' + '9' + 1;
436 c
= c
- 'A' + '9' + 1;
450 value
= radix
* value
;
452 if (maxv
- c
< value
)
457 v
= (signed int) value
;
461 set_integer (dest
, v
, length
);
465 generate_error (ERROR_READ_VALUE
, "Bad value during integer read");
469 generate_error (ERROR_READ_OVERFLOW
,
470 "Value overflowed during integer read");
475 /* read_f()-- Read a floating point number with F-style editing, which
476 is what all of the other floating point descriptors behave as. The
477 tricky part is that optional spaces are allowed after an E or D,
478 and the implicit decimal point if a decimal point is not present in
482 read_f (fnode
* f
, char *dest
, int length
)
484 int w
, seen_dp
, exponent
;
485 int exponent_sign
, val_sign
;
499 p
= eat_leading_spaces (&w
, p
);
505 *((float *) dest
) = 0.0f
;
509 *((double *) dest
) = 0.0;
513 internal_error ("Unsupported real kind during IO");
521 if (*p
== '-' || *p
== '+')
533 /* A digit (or a '.') is required at this point */
535 if (!isdigit (*p
) && *p
!= '.')
538 /* Remember the position of the first digit. */
542 /* Scan through the string to find the exponent. */
591 /* No exponent has been seen, so we use the current scale factor */
593 exponent
= -g
.scale_factor
;
597 generate_error (ERROR_READ_VALUE
, "Bad value during floating point read");
598 if (buffer
!= scratch
)
602 /* At this point the start of an exponent has been found */
605 while (w
> 0 && *p
== ' ')
626 /* At this point a digit string is required. We calculate the value
627 of the exponent in order to take account of the scale factor and
628 the d parameter before explict conversion takes place. */
638 while (w
> 0 && isdigit (*p
))
640 exponent
= 10 * exponent
+ *p
- '0';
645 /* Only allow trailing blanks */
655 exponent
= exponent
* exponent_sign
;
658 /* Use the precision specified in the format if no decimal point has been
661 exponent
-= f
->u
.real
.d
;
680 i
= ndigits
+ edigits
+ 1;
684 if (i
< SCRATCH_SIZE
)
687 buffer
= get_mem (i
);
689 /* Reformat the string into a temporary buffer. As we're using atof it's
690 easiest to just leave the dcimal point in place. */
694 for (; ndigits
> 0; ndigits
--)
696 if (*digits
== ' ' && g
.blank_status
== BLANK_ZERO
)
704 sprintf (p
, "%d", exponent
);
706 /* Do the actual conversion. */
707 convert_real (dest
, buffer
, length
);
709 if (buffer
!= scratch
)
716 /* read_x()-- Deal with the X/TR descriptor. We just read some data
717 * and never look at it. */