1 /*******************************************************************************
2  *
3  * Module Name: utstrsuppt - Support functions for string-to-integer conversion
4  *
5  ******************************************************************************/
6 
7 /******************************************************************************
8  *
9  * 1. Copyright Notice
10  *
11  * Some or all of this work - Copyright (c) 1999 - 2018, Intel Corp.
12  * All rights reserved.
13  *
14  * 2. License
15  *
16  * 2.1. This is your license from Intel Corp. under its intellectual property
17  * rights. You may have additional license terms from the party that provided
18  * you this software, covering your right to use that party's intellectual
19  * property rights.
20  *
21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
22  * copy of the source code appearing in this file ("Covered Code") an
23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
24  * base code distributed originally by Intel ("Original Intel Code") to copy,
25  * make derivatives, distribute, use and display any portion of the Covered
26  * Code in any form, with the right to sublicense such rights; and
27  *
28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
29  * license (with the right to sublicense), under only those claims of Intel
30  * patents that are infringed by the Original Intel Code, to make, use, sell,
31  * offer to sell, and import the Covered Code and derivative works thereof
32  * solely to the minimum extent necessary to exercise the above copyright
33  * license, and in no event shall the patent license extend to any additions
34  * to or modifications of the Original Intel Code. No other license or right
35  * is granted directly or by implication, estoppel or otherwise;
36  *
37  * The above copyright and patent license is granted only if the following
38  * conditions are met:
39  *
40  * 3. Conditions
41  *
42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
43  * Redistribution of source code of any substantial portion of the Covered
44  * Code or modification with rights to further distribute source must include
45  * the above Copyright Notice, the above License, this list of Conditions,
46  * and the following Disclaimer and Export Compliance provision. In addition,
47  * Licensee must cause all Covered Code to which Licensee contributes to
48  * contain a file documenting the changes Licensee made to create that Covered
49  * Code and the date of any change. Licensee must include in that file the
50  * documentation of any changes made by any predecessor Licensee. Licensee
51  * must include a prominent statement that the modification is derived,
52  * directly or indirectly, from Original Intel Code.
53  *
54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
55  * Redistribution of source code of any substantial portion of the Covered
56  * Code or modification without rights to further distribute source must
57  * include the following Disclaimer and Export Compliance provision in the
58  * documentation and/or other materials provided with distribution. In
59  * addition, Licensee may not authorize further sublicense of source of any
60  * portion of the Covered Code, and must include terms to the effect that the
61  * license from Licensee to its licensee is limited to the intellectual
62  * property embodied in the software Licensee provides to its licensee, and
63  * not to intellectual property embodied in modifications its licensee may
64  * make.
65  *
66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
67  * substantial portion of the Covered Code or modification must reproduce the
68  * above Copyright Notice, and the following Disclaimer and Export Compliance
69  * provision in the documentation and/or other materials provided with the
70  * distribution.
71  *
72  * 3.4. Intel retains all right, title, and interest in and to the Original
73  * Intel Code.
74  *
75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
76  * Intel shall be used in advertising or otherwise to promote the sale, use or
77  * other dealings in products derived from or relating to the Covered Code
78  * without prior written authorization from Intel.
79  *
80  * 4. Disclaimer and Export Compliance
81  *
82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
83  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
85  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
86  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
88  * PARTICULAR PURPOSE.
89  *
90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
97  * LIMITED REMEDY.
98  *
99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
100  * software or system incorporating such software without first obtaining any
101  * required license or other approval from the U. S. Department of Commerce or
102  * any other agency or department of the United States Government. In the
103  * event Licensee exports any such software from the United States or
104  * re-exports any such software from a foreign destination, Licensee shall
105  * ensure that the distribution and export/re-export of the software is in
106  * compliance with all laws, regulations, orders, or other restrictions of the
107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
108  * any of its subsidiaries will export/re-export any technical data, process,
109  * software, or service, directly or indirectly, to any country for which the
110  * United States government or any agency thereof requires an export license,
111  * other governmental approval, or letter of assurance, without first obtaining
112  * such license, approval or letter.
113  *
114  *****************************************************************************
115  *
116  * Alternatively, you may choose to be licensed under the terms of the
117  * following license:
118  *
119  * Redistribution and use in source and binary forms, with or without
120  * modification, are permitted provided that the following conditions
121  * are met:
122  * 1. Redistributions of source code must retain the above copyright
123  *    notice, this list of conditions, and the following disclaimer,
124  *    without modification.
125  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
126  *    substantially similar to the "NO WARRANTY" disclaimer below
127  *    ("Disclaimer") and any redistribution must be conditioned upon
128  *    including a substantially similar Disclaimer requirement for further
129  *    binary redistribution.
130  * 3. Neither the names of the above-listed copyright holders nor the names
131  *    of any contributors may be used to endorse or promote products derived
132  *    from this software without specific prior written permission.
133  *
134  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
135  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
136  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
137  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
138  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
139  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
140  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
141  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
142  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
143  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
144  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
145  *
146  * Alternatively, you may choose to be licensed under the terms of the
147  * GNU General Public License ("GPL") version 2 as published by the Free
148  * Software Foundation.
149  *
150  *****************************************************************************/
151 
152 #include "acpi.h"
153 #include "accommon.h"
154 
155 #define _COMPONENT          ACPI_UTILITIES
156         ACPI_MODULE_NAME    ("utstrsuppt")
157 
158 
159 /* Local prototypes */
160 
161 static ACPI_STATUS
162 AcpiUtInsertDigit (
163     UINT64                  *AccumulatedValue,
164     UINT32                  Base,
165     int                     AsciiDigit);
166 
167 static ACPI_STATUS
168 AcpiUtStrtoulMultiply64 (
169     UINT64                  Multiplicand,
170     UINT32                  Base,
171     UINT64                  *OutProduct);
172 
173 static ACPI_STATUS
174 AcpiUtStrtoulAdd64 (
175     UINT64                  Addend1,
176     UINT32                  Digit,
177     UINT64                  *OutSum);
178 
179 
180 /*******************************************************************************
181  *
182  * FUNCTION:    AcpiUtConvertOctalString
183  *
184  * PARAMETERS:  String                  - Null terminated input string
185  *              ReturnValuePtr          - Where the converted value is returned
186  *
187  * RETURN:      Status and 64-bit converted integer
188  *
189  * DESCRIPTION: Performs a base 8 conversion of the input string to an
190  *              integer value, either 32 or 64 bits.
191  *
192  * NOTE:        Maximum 64-bit unsigned octal value is 01777777777777777777777
193  *              Maximum 32-bit unsigned octal value is 037777777777
194  *
195  ******************************************************************************/
196 
197 ACPI_STATUS
198 AcpiUtConvertOctalString (
199     char                    *String,
200     UINT64                  *ReturnValuePtr)
201 {
202     UINT64                  AccumulatedValue = 0;
203     ACPI_STATUS             Status = AE_OK;
204 
205 
206     /* Convert each ASCII byte in the input string */
207 
208     while (*String)
209     {
210         /* Character must be ASCII 0-7, otherwise terminate with no error */
211 
212         if (!(ACPI_IS_OCTAL_DIGIT (*String)))
213         {
214             break;
215         }
216 
217         /* Convert and insert this octal digit into the accumulator */
218 
219         Status = AcpiUtInsertDigit (&AccumulatedValue, 8, *String);
220         if (ACPI_FAILURE (Status))
221         {
222             Status = AE_OCTAL_OVERFLOW;
223             break;
224         }
225 
226         String++;
227     }
228 
229     /* Always return the value that has been accumulated */
230 
231     *ReturnValuePtr = AccumulatedValue;
232     return (Status);
233 }
234 
235 
236 /*******************************************************************************
237  *
238  * FUNCTION:    AcpiUtConvertDecimalString
239  *
240  * PARAMETERS:  String                  - Null terminated input string
241  *              ReturnValuePtr          - Where the converted value is returned
242  *
243  * RETURN:      Status and 64-bit converted integer
244  *
245  * DESCRIPTION: Performs a base 10 conversion of the input string to an
246  *              integer value, either 32 or 64 bits.
247  *
248  * NOTE:        Maximum 64-bit unsigned decimal value is 18446744073709551615
249  *              Maximum 32-bit unsigned decimal value is 4294967295
250  *
251  ******************************************************************************/
252 
253 ACPI_STATUS
254 AcpiUtConvertDecimalString (
255     char                    *String,
256     UINT64                  *ReturnValuePtr)
257 {
258     UINT64                  AccumulatedValue = 0;
259     ACPI_STATUS             Status = AE_OK;
260 
261 
262     /* Convert each ASCII byte in the input string */
263 
264     while (*String)
265     {
266         /* Character must be ASCII 0-9, otherwise terminate with no error */
267 
268         if (!isdigit (*String))
269         {
270            break;
271         }
272 
273         /* Convert and insert this decimal digit into the accumulator */
274 
275         Status = AcpiUtInsertDigit (&AccumulatedValue, 10, *String);
276         if (ACPI_FAILURE (Status))
277         {
278             Status = AE_DECIMAL_OVERFLOW;
279             break;
280         }
281 
282         String++;
283     }
284 
285     /* Always return the value that has been accumulated */
286 
287     *ReturnValuePtr = AccumulatedValue;
288     return (Status);
289 }
290 
291 
292 /*******************************************************************************
293  *
294  * FUNCTION:    AcpiUtConvertHexString
295  *
296  * PARAMETERS:  String                  - Null terminated input string
297  *              ReturnValuePtr          - Where the converted value is returned
298  *
299  * RETURN:      Status and 64-bit converted integer
300  *
301  * DESCRIPTION: Performs a base 16 conversion of the input string to an
302  *              integer value, either 32 or 64 bits.
303  *
304  * NOTE:        Maximum 64-bit unsigned hex value is 0xFFFFFFFFFFFFFFFF
305  *              Maximum 32-bit unsigned hex value is 0xFFFFFFFF
306  *
307  ******************************************************************************/
308 
309 ACPI_STATUS
310 AcpiUtConvertHexString (
311     char                    *String,
312     UINT64                  *ReturnValuePtr)
313 {
314     UINT64                  AccumulatedValue = 0;
315     ACPI_STATUS             Status = AE_OK;
316 
317 
318     /* Convert each ASCII byte in the input string */
319 
320     while (*String)
321     {
322         /* Must be ASCII A-F, a-f, or 0-9, otherwise terminate with no error */
323 
324         if (!isxdigit (*String))
325         {
326             break;
327         }
328 
329         /* Convert and insert this hex digit into the accumulator */
330 
331         Status = AcpiUtInsertDigit (&AccumulatedValue, 16, *String);
332         if (ACPI_FAILURE (Status))
333         {
334             Status = AE_HEX_OVERFLOW;
335             break;
336         }
337 
338         String++;
339     }
340 
341     /* Always return the value that has been accumulated */
342 
343     *ReturnValuePtr = AccumulatedValue;
344     return (Status);
345 }
346 
347 
348 /*******************************************************************************
349  *
350  * FUNCTION:    AcpiUtRemoveLeadingZeros
351  *
352  * PARAMETERS:  String                  - Pointer to input ASCII string
353  *
354  * RETURN:      Next character after any leading zeros. This character may be
355  *              used by the caller to detect end-of-string.
356  *
357  * DESCRIPTION: Remove any leading zeros in the input string. Return the
358  *              next character after the final ASCII zero to enable the caller
359  *              to check for the end of the string (NULL terminator).
360  *
361  ******************************************************************************/
362 
363 char
364 AcpiUtRemoveLeadingZeros (
365     char                    **String)
366 {
367 
368     while (**String == ACPI_ASCII_ZERO)
369     {
370         *String += 1;
371     }
372 
373     return (**String);
374 }
375 
376 
377 /*******************************************************************************
378  *
379  * FUNCTION:    AcpiUtRemoveWhitespace
380  *
381  * PARAMETERS:  String                  - Pointer to input ASCII string
382  *
383  * RETURN:      Next character after any whitespace. This character may be
384  *              used by the caller to detect end-of-string.
385  *
386  * DESCRIPTION: Remove any leading whitespace in the input string. Return the
387  *              next character after the final ASCII zero to enable the caller
388  *              to check for the end of the string (NULL terminator).
389  *
390  ******************************************************************************/
391 
392 char
393 AcpiUtRemoveWhitespace (
394     char                    **String)
395 {
396 
397     while (isspace ((UINT8) **String))
398     {
399         *String += 1;
400     }
401 
402     return (**String);
403 }
404 
405 
406 /*******************************************************************************
407  *
408  * FUNCTION:    AcpiUtDetectHexPrefix
409  *
410  * PARAMETERS:  String                  - Pointer to input ASCII string
411  *
412  * RETURN:      TRUE if a "0x" prefix was found at the start of the string
413  *
414  * DESCRIPTION: Detect and remove a hex "0x" prefix
415  *
416  ******************************************************************************/
417 
418 BOOLEAN
419 AcpiUtDetectHexPrefix (
420     char                    **String)
421 {
422 
423     if ((**String == ACPI_ASCII_ZERO) &&
424         (tolower ((int) *(*String + 1)) == 'x'))
425     {
426         *String += 2;        /* Go past the leading 0x */
427         return (TRUE);
428     }
429 
430     return (FALSE);     /* Not a hex string */
431 }
432 
433 
434 /*******************************************************************************
435  *
436  * FUNCTION:    AcpiUtDetectOctalPrefix
437  *
438  * PARAMETERS:  String                  - Pointer to input ASCII string
439  *
440  * RETURN:      True if an octal "0" prefix was found at the start of the
441  *              string
442  *
443  * DESCRIPTION: Detect and remove an octal prefix (zero)
444  *
445  ******************************************************************************/
446 
447 BOOLEAN
448 AcpiUtDetectOctalPrefix (
449     char                    **String)
450 {
451 
452     if (**String == ACPI_ASCII_ZERO)
453     {
454         *String += 1;       /* Go past the leading 0 */
455         return (TRUE);
456     }
457 
458     return (FALSE);     /* Not an octal string */
459 }
460 
461 
462 /*******************************************************************************
463  *
464  * FUNCTION:    AcpiUtInsertDigit
465  *
466  * PARAMETERS:  AccumulatedValue        - Current value of the integer value
467  *                                        accumulator. The new value is
468  *                                        returned here.
469  *              Base                    - Radix, either 8/10/16
470  *              AsciiDigit              - ASCII single digit to be inserted
471  *
472  * RETURN:      Status and result of the convert/insert operation. The only
473  *              possible returned exception code is numeric overflow of
474  *              either the multiply or add conversion operations.
475  *
476  * DESCRIPTION: Generic conversion and insertion function for all bases:
477  *
478  *              1) Multiply the current accumulated/converted value by the
479  *              base in order to make room for the new character.
480  *
481  *              2) Convert the new character to binary and add it to the
482  *              current accumulated value.
483  *
484  *              Note: The only possible exception indicates an integer
485  *              overflow (AE_NUMERIC_OVERFLOW)
486  *
487  ******************************************************************************/
488 
489 static ACPI_STATUS
490 AcpiUtInsertDigit (
491     UINT64                  *AccumulatedValue,
492     UINT32                  Base,
493     int                     AsciiDigit)
494 {
495     ACPI_STATUS             Status;
496     UINT64                  Product;
497 
498 
499      /* Make room in the accumulated value for the incoming digit */
500 
501     Status = AcpiUtStrtoulMultiply64 (*AccumulatedValue, Base, &Product);
502     if (ACPI_FAILURE (Status))
503     {
504         return (Status);
505     }
506 
507     /* Add in the new digit, and store the sum to the accumulated value */
508 
509     Status = AcpiUtStrtoulAdd64 (Product, AcpiUtAsciiCharToHex (AsciiDigit),
510         AccumulatedValue);
511 
512     return (Status);
513 }
514 
515 
516 /*******************************************************************************
517  *
518  * FUNCTION:    AcpiUtStrtoulMultiply64
519  *
520  * PARAMETERS:  Multiplicand            - Current accumulated converted integer
521  *              Base                    - Base/Radix
522  *              OutProduct              - Where the product is returned
523  *
524  * RETURN:      Status and 64-bit product
525  *
526  * DESCRIPTION: Multiply two 64-bit values, with checking for 64-bit overflow as
527  *              well as 32-bit overflow if necessary (if the current global
528  *              integer width is 32).
529  *
530  ******************************************************************************/
531 
532 static ACPI_STATUS
533 AcpiUtStrtoulMultiply64 (
534     UINT64                  Multiplicand,
535     UINT32                  Base,
536     UINT64                  *OutProduct)
537 {
538     UINT64                  Product;
539     UINT64                  Quotient;
540 
541 
542     /* Exit if either operand is zero */
543 
544     *OutProduct = 0;
545     if (!Multiplicand || !Base)
546     {
547         return (AE_OK);
548     }
549 
550     /*
551      * Check for 64-bit overflow before the actual multiplication.
552      *
553      * Notes: 64-bit division is often not supported on 32-bit platforms
554      * (it requires a library function), Therefore ACPICA has a local
555      * 64-bit divide function. Also, Multiplier is currently only used
556      * as the radix (8/10/16), to the 64/32 divide will always work.
557      */
558     AcpiUtShortDivide (ACPI_UINT64_MAX, Base, &Quotient, NULL);
559     if (Multiplicand > Quotient)
560     {
561         return (AE_NUMERIC_OVERFLOW);
562     }
563 
564     Product = Multiplicand * Base;
565 
566     /* Check for 32-bit overflow if necessary */
567 
568     if ((AcpiGbl_IntegerBitWidth == 32) && (Product > ACPI_UINT32_MAX))
569     {
570         return (AE_NUMERIC_OVERFLOW);
571     }
572 
573     *OutProduct = Product;
574     return (AE_OK);
575 }
576 
577 
578 /*******************************************************************************
579  *
580  * FUNCTION:    AcpiUtStrtoulAdd64
581  *
582  * PARAMETERS:  Addend1                 - Current accumulated converted integer
583  *              Digit                   - New hex value/char
584  *              OutSum                  - Where sum is returned (Accumulator)
585  *
586  * RETURN:      Status and 64-bit sum
587  *
588  * DESCRIPTION: Add two 64-bit values, with checking for 64-bit overflow as
589  *              well as 32-bit overflow if necessary (if the current global
590  *              integer width is 32).
591  *
592  ******************************************************************************/
593 
594 static ACPI_STATUS
595 AcpiUtStrtoulAdd64 (
596     UINT64                  Addend1,
597     UINT32                  Digit,
598     UINT64                  *OutSum)
599 {
600     UINT64                  Sum;
601 
602 
603     /* Check for 64-bit overflow before the actual addition */
604 
605     if ((Addend1 > 0) && (Digit > (ACPI_UINT64_MAX - Addend1)))
606     {
607         return (AE_NUMERIC_OVERFLOW);
608     }
609 
610     Sum = Addend1 + Digit;
611 
612     /* Check for 32-bit overflow if necessary */
613 
614     if ((AcpiGbl_IntegerBitWidth == 32) && (Sum > ACPI_UINT32_MAX))
615     {
616         return (AE_NUMERIC_OVERFLOW);
617     }
618 
619     *OutSum = Sum;
620     return (AE_OK);
621 }
622