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+/*
+ * Copyright (c) 2021-2025 Symas Corporation
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of the Symas Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <algorithm>
+#include <cctype>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <ctime>
+#include <set>
+#include <stack>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+#include <dirent.h>
+#include <dlfcn.h>
+#include <err.h>
+#include <fcntl.h>
+#include <fenv.h>
+#include <math.h> // required for fpclassify(3), not in cmath
+#include <setjmp.h>
+#include <signal.h>
+#include <syslog.h>
+#include <unistd.h>
+#include <stdarg.h>
+#if __has_include(<errno.h>)
+# include <errno.h> // for program_invocation_short_name
+#endif
+
+#include "config.h"
+#include "libgcobol-fp.h"
+
+#include "ec.h"
+#include "common-defs.h"
+#include "io.h"
+#include "gcobolio.h"
+#include "libgcobol.h"
+#include "gfileio.h"
+#include "charmaps.h"
+#include "valconv.h"
+#include <sys/mman.h>
+#include <sys/resource.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include <execinfo.h>
+#include "exceptl.h"
+#include "stringbin.h"
+
+/* This routine evolved from a primitive binary-to-string routine that simply
+ peeled digits off the bottom of an __int128 by using
+
+ value % 10 + '0';
+ value /= 10;
+
+ That turns out to be unnecessarily slow.
+
+ The routine implemented here uses a divide-and-conquer approach to
+ minimimizing the number of operations, and when you get down to two
+ digits it does a divide-by-100 and uses the remainder in a table lookup
+ to get the digits. */
+
+/* These static tables are born of a pathologic desire to avoid calculations.
+ Whether that paranoia is justified (perhaps "digit%10 + '0';" ) would
+ actually be faster) is currently untested. But I figured this would be
+ pretty darn fast.
+
+ Use them when you know the index is between zero and one hundred. */
+
+static const char digit_low[100] =
+ {
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
+ };
+
+static const char digit_high[100] =
+ {
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ };
+
+static char combined_string[128];
+static char zero_char;
+
+typedef struct
+ {
+ int start;
+ int run;
+ union
+ {
+ unsigned __int128 val128;
+ uint64_t val64;
+ uint32_t val32;
+ uint16_t val16;
+ uint8_t val8;
+ };
+ } COMBINED;
+
+static
+void
+string_from_combined(const COMBINED &combined)
+ {
+ COMBINED left;
+ COMBINED right;
+
+ uint16_t v16;
+
+ switch(combined.run)
+ {
+ case 1:
+ // We know that val8 is a single digit
+ combined_string[combined.start] = combined.val8 + zero_char;;
+ break;
+
+ case 2:
+ // We know that val8 has two digits
+ combined_string[combined.start] = digit_high[combined.val8] + zero_char;
+ combined_string[combined.start+1] = digit_low [combined.val8] + zero_char;
+ break;
+
+ case 3:
+ // We know that val16 has three digits.
+ v16 = combined.val16;
+ combined_string[combined.start] = v16 / 100 + zero_char;
+ v16 %= 100;
+ combined_string[combined.start+1] = v16 / 10 + zero_char;
+ combined_string[combined.start+2] = v16 % 10 + zero_char;
+ break;
+
+ case 4:
+ // We know that val16 has four digits:
+ v16 = combined.val16;
+ combined_string[combined.start] = v16 / 1000 + zero_char;
+ v16 %= 1000;
+ combined_string[combined.start+1] = v16 / 100 + zero_char;
+ v16 %= 100;
+ combined_string[combined.start+2] = v16 / 10 + zero_char;
+ combined_string[combined.start+3] = v16 % 10 + zero_char;
+ break;
+
+ case 5:
+ case 6:
+ case 7:
+ case 8:
+ // We know that val32 can be treated as two 4-digit pieces
+ left.start = combined.start;
+ left.run = combined.run - 4;
+ left.val16 = combined.val32 / 10000;
+
+ right.start = combined.start+left.run;
+ right.run = 4;
+ right.val16 = combined.val32 % 10000;
+
+ string_from_combined(left);
+ string_from_combined(right);
+ break;
+
+ case 9:
+ // We break val32 into a 1-digit piece, and an 8-digit piece:
+ left.start = combined.start;
+ left.run = combined.run - 8;
+ left.val32 = combined.val32 / 100000000;
+
+ right.start = combined.start+left.run;
+ right.run = 8;
+ right.val32 = combined.val32 % 100000000;
+
+ string_from_combined(left);
+ string_from_combined(right);
+ break;
+
+ case 10:
+ case 11:
+ case 12:
+ case 13:
+ case 14:
+ case 15:
+ case 16:
+ case 17:
+ case 18:
+ // We know we can treat val64 as two 9-digit pieces:
+ left.start = combined.start;
+ left.run = combined.run - 9;
+ left.val32 = combined.val64 / 1000000000;
+
+ right.start = combined.start+left.run;
+ right.run = 9;
+ right.val32 = combined.val64 % 1000000000;
+
+ string_from_combined(left);
+ string_from_combined(right);
+ break;
+
+ case 19:
+ // We split off the bottom nine digits
+ left.start = combined.start;
+ left.run = combined.run - 9;
+ left.val64 = combined.val64 / 1000000000;
+
+ right.start = combined.start+left.run;
+ right.run = 9;
+ right.val32 = combined.val64 % 1000000000;
+
+ string_from_combined(left);
+ string_from_combined(right);
+ break;
+
+ default:
+ // For twenty or more digits we peel eighteen digits at a time off the
+ // right side:
+ left.start = combined.start;
+ left.run = combined.run - 18;
+ left.val128 = combined.val128 / 1000000000000000000ULL;
+
+ right.start = combined.start+left.run;
+ right.run = 18;
+ right.val64 = combined.val128 % 1000000000000000000ULL;
+
+ string_from_combined(left);
+ string_from_combined(right);
+ break;
+ }
+ }
+
+bool
+__gg__binary_to_string_ascii(char *result, int digits, __int128 value)
+ {
+ zero_char = ascii_zero;
+
+ // Note that this routine does not terminate the generated string with a
+ // NUL. This routine is sometimes used to generate a NumericDisplay string
+ // of digits in place, with no terminator.
+ __int128 mask = __gg__power_of_ten(digits);
+
+ COMBINED combined;
+ if( value < 0 )
+ {
+ value = -value;
+ }
+
+ // A non-zero retval means the number was too big to fit into the desired
+ // number of digits:
+ bool retval = !!(value / mask);
+
+ // mask off the bottom digits to avoid garbage when value is too large
+ value %= mask;
+
+ combined.start = 0;
+ combined.run = digits;
+ combined.val128 = value;
+ string_from_combined(combined);
+ memcpy(result, combined_string, digits);
+ return retval;
+ }
+
+bool
+__gg__binary_to_string_internal(char *result, int digits, __int128 value)
+ {
+ zero_char = internal_zero;
+
+ // Note that this routine does not terminate the generated string with a
+ // NUL. This routine is sometimes used to generate a NumericDisplay string
+ // of digits in place, with no terminator.
+ __int128 mask = __gg__power_of_ten(digits);
+
+ COMBINED combined;
+ if( value < 0 )
+ {
+ value = -value;
+ }
+
+ // A non-zero retval means the number was too big to fit into the desired
+ // number of digits:
+ bool retval = !!(value / mask);
+
+ // mask off the bottom digits to avoid garbage when value is too large
+ value %= mask;
+
+ combined.start = 0;
+ combined.run = digits;
+ combined.val128 = value;
+ string_from_combined(combined);
+ memcpy(result, combined_string, digits);
+ return retval;
+ }
+
generated by cgit v1.1 at 2025-08-08 03:23:35 +0000