--- /dev/null
+/* PSPP - computes sample statistics.
+ Copyright (C) 2006 Free Software Foundation, Inc.
+ Written by Ben Pfaff <blp@gnu.org>.
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ 02110-1301, USA. */
+
+#include <config.h>
+
+#include <libpspp/float-format.h>
+
+#include "gettext.h"
+#include <inttypes.h>
+
+#include <language/command.h>
+#include <language/lexer/lexer.h>
+#include <libpspp/assertion.h>
+#include <libpspp/message.h>
+#include <libpspp/str.h>
+
+#define _(msgid) gettext (msgid)
+
+/* Maximum supported size of a floating-point number, in bytes. */
+#define FP_MAX_SIZE 32
+
+/* A floating-point number tagged with its representation. */
+struct fp
+ {
+ enum float_format format; /* Format. */
+ uint8_t data[FP_MAX_SIZE]; /* Representation. */
+ };
+
+/* Associates a format name with its identifier. */
+struct assoc
+ {
+ char name[4];
+ enum float_format format;
+ };
+
+/* List of floating-point formats. */
+static const struct assoc fp_formats[] =
+ {
+ {"ISL", FLOAT_IEEE_SINGLE_LE},
+ {"ISB", FLOAT_IEEE_SINGLE_BE},
+ {"IDL", FLOAT_IEEE_DOUBLE_LE},
+ {"IDB", FLOAT_IEEE_DOUBLE_BE},
+ {"VF", FLOAT_VAX_F},
+ {"VD", FLOAT_VAX_D},
+ {"VG", FLOAT_VAX_G},
+ {"ZS", FLOAT_Z_SHORT},
+ {"ZL", FLOAT_Z_LONG},
+ {"X", FLOAT_HEX},
+ {"FP", FLOAT_FP},
+ };
+static const size_t format_cnt = sizeof fp_formats / sizeof *fp_formats;
+
+/* Parses a floating-point format name into *FORMAT,
+ and returns success. */
+static bool
+parse_float_format (enum float_format *format)
+{
+ size_t i;
+
+ for (i = 0; i < format_cnt; i++)
+ if (lex_match_id (fp_formats[i].name))
+ {
+ *format = fp_formats[i].format;
+ return true;
+ }
+ lex_error ("expecting floating-point format identifier");
+ return false;
+}
+
+/* Returns the name for the given FORMAT. */
+static const char *
+get_float_format_name (enum float_format format)
+{
+ size_t i;
+
+ for (i = 0; i < format_cnt; i++)
+ if (fp_formats[i].format == format)
+ return fp_formats[i].name;
+
+ NOT_REACHED ();
+}
+
+/* Parses a number in the form FORMAT(STRING), where FORMAT is
+ the name of the format and STRING gives the number's
+ representation. Also supports ordinary floating-point numbers
+ written in decimal notation. Returns success. */
+static bool
+parse_fp (struct fp *fp)
+{
+ if (lex_is_number ())
+ {
+ double number = lex_number ();
+ fp->format = FLOAT_NATIVE_DOUBLE;
+ memcpy (fp->data, &number, sizeof number);
+ lex_get ();
+ }
+ else if (token == T_ID)
+ {
+ size_t length;
+
+ if (!parse_float_format (&fp->format)
+ || !lex_force_match ('(')
+ || !lex_force_string ())
+ return false;
+
+ length = ds_length (&tokstr);
+ if (fp->format != FLOAT_HEX)
+ {
+ if (length != float_get_size (fp->format))
+ {
+ msg (SE, _("%d-byte string needed but %d-byte string supplied."),
+ (int) float_get_size (fp->format), (int) length);
+ return false;
+ }
+ assert (length <= sizeof fp->data);
+ memcpy (fp->data, ds_data (&tokstr), length);
+ }
+ else
+ {
+ if (length >= sizeof fp->data)
+ {
+ msg (SE, _("Hexadecimal floating constant too long."));
+ return false;
+ }
+ strncpy ((char *) fp->data, ds_cstr (&tokstr), sizeof fp->data);
+ }
+
+ lex_get ();
+ if (!lex_force_match (')'))
+ return false;
+ }
+ else
+ {
+ lex_error (NULL);
+ return false;
+ }
+ return true;
+}
+
+/* Renders SRC, which contains SRC_SIZE bytes of a floating-point
+ number in the given FORMAT, as relatively human-readable
+ null-terminated string in the DST_SIZE bytes in DST. DST_SIZE
+ must be be large enough to hold the output. */
+static void
+make_printable (enum float_format format, const void *src_, size_t src_size,
+ char *dst, size_t dst_size)
+{
+ assert (dst_size >= 2 * src_size + 1);
+ if (format != FLOAT_HEX)
+ {
+ const uint8_t *src = src_;
+ while (src_size-- > 0)
+ {
+ sprintf (dst, "%02x", *src++);
+ dst += 2;
+ }
+ *dst = '\0';
+ }
+ else
+ strncpy (dst, src_, src_size + 1);
+}
+
+/* Checks that RESULT is identical to TO.
+ If so, returns false.
+ If not, issues a helpful error message that includes the given
+ CONVERSION_TYPE and the value that was converted FROM, and
+ returns true. */
+static bool
+mismatch (const struct fp *from, const struct fp *to, char *result,
+ const char *conversion_type)
+{
+ size_t to_size = float_get_size (to->format);
+ if (!memcmp (to->data, result, to_size))
+ return false;
+ else
+ {
+ size_t from_size = float_get_size (from->format);
+ char original[FP_MAX_SIZE * 2 + 1];
+ char expected[FP_MAX_SIZE * 2 + 1];
+ char actual[FP_MAX_SIZE * 2 + 1];
+ make_printable (from->format, from->data, from_size, original,
+ sizeof original);
+ make_printable (to->format, to->data, to_size, expected,
+ sizeof expected);
+ make_printable (to->format, result, to_size, actual, sizeof actual);
+ msg (SE,
+ _("%s conversion of %s from %s to %s should have produced %s "
+ "but actually produced %s."),
+ conversion_type,
+ original, get_float_format_name (from->format),
+ get_float_format_name (to->format), expected,
+ actual);
+ return true;
+ }
+}
+
+/* Checks that converting FROM into the format of TO yields
+ exactly the data in TO. */
+static bool
+verify_conversion (const struct fp *from, const struct fp *to)
+{
+ char tmp1[FP_MAX_SIZE], tmp2[FP_MAX_SIZE];
+
+ /* First try converting directly. */
+ float_convert (from->format, from->data, to->format, tmp1);
+ if (mismatch (from, to, tmp1, "Direct"))
+ return false;
+
+ /* Then convert via FLOAT_FP to prevent short-circuiting that
+ float_convert() does for some conversions (e.g. little<->big
+ endian for IEEE formats). */
+ float_convert (from->format, from->data, FLOAT_FP, tmp1);
+ float_convert (FLOAT_FP, tmp1, to->format, tmp2);
+ if (mismatch (from, to, tmp2, "Indirect"))
+ return false;
+
+ return true;
+}
+
+/* Executes the DEBUG FLOAT FORMAT command. */
+int
+cmd_debug_float_format (struct dataset *ds UNUSED)
+{
+ struct fp fp[16];
+ size_t fp_cnt = 0;
+ bool bijective = false;
+ bool ok;
+
+ for (;;)
+ {
+ if (fp_cnt >= sizeof fp / sizeof *fp)
+ {
+ msg (SE, _("Too many values in single command."));
+ return CMD_FAILURE;
+ }
+ if (!parse_fp (&fp[fp_cnt++]))
+ return CMD_FAILURE;
+
+ if (token == '.' && fp_cnt > 1)
+ break;
+ else if (!lex_force_match ('='))
+ return CMD_FAILURE;
+
+ if (fp_cnt == 1)
+ {
+ if (lex_match ('='))
+ bijective = true;
+ else if (lex_match (T_GT))
+ bijective = false;
+ else
+ {
+ lex_error (NULL);
+ return CMD_FAILURE;
+ }
+ }
+ else
+ {
+ if ((bijective && !lex_force_match ('='))
+ || (!bijective && !lex_force_match (T_GT)))
+ return CMD_FAILURE;
+ }
+ }
+
+ ok = true;
+ if (bijective)
+ {
+ size_t i, j;
+
+ for (i = 0; i < fp_cnt; i++)
+ for (j = 0; j < fp_cnt; j++)
+ if (!verify_conversion (&fp[i], &fp[j]))
+ ok = false;
+ }
+ else
+ {
+ size_t i;
+
+ for (i = 1; i < fp_cnt; i++)
+ if (!verify_conversion (&fp[i - 1], &fp[i]))
+ ok = false;
+ }
+
+ return ok ? CMD_SUCCESS : CMD_FAILURE;
+}
projects / pspp-builds.git / blobdiff