1/*******************************************************************************
2 *
3 * Module Name: utstrtoul64 - String-to-integer conversion support for both
4 *                            64-bit and 32-bit integers
5 *
6 ******************************************************************************/
7
8/*
9 * Copyright (C) 2000 - 2023, Intel Corp.
10 * All rights reserved.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions, and the following disclaimer,
17 *    without modification.
18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19 *    substantially similar to the "NO WARRANTY" disclaimer below
20 *    ("Disclaimer") and any redistribution must be conditioned upon
21 *    including a substantially similar Disclaimer requirement for further
22 *    binary redistribution.
23 * 3. Neither the names of the above-listed copyright holders nor the names
24 *    of any contributors may be used to endorse or promote products derived
25 *    from this software without specific prior written permission.
26 *
27 * Alternatively, this software may be distributed under the terms of the
28 * GNU General Public License ("GPL") version 2 as published by the Free
29 * Software Foundation.
30 *
31 * NO WARRANTY
32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42 * POSSIBILITY OF SUCH DAMAGES.
43 */
44
45#include "acpi.h"
46#include "accommon.h"
47
48#define _COMPONENT          ACPI_UTILITIES
49        ACPI_MODULE_NAME    ("utstrtoul64")
50
51
52/*******************************************************************************
53 *
54 * This module contains the top-level string to 64/32-bit unsigned integer
55 * conversion functions:
56 *
57 *  1) A standard strtoul() function that supports 64-bit integers, base
58 *     8/10/16, with integer overflow support. This is used mainly by the
59 *     iASL compiler, which implements tighter constraints on integer
60 *     constants than the runtime (interpreter) integer-to-string conversions.
61 *  2) Runtime "Explicit conversion" as defined in the ACPI specification.
62 *  3) Runtime "Implicit conversion" as defined in the ACPI specification.
63 *
64 * Current users of this module:
65 *
66 *  iASL        - Preprocessor (constants and math expressions)
67 *  iASL        - Main parser, conversion of constants to integers
68 *  iASL        - Data Table Compiler parser (constants and math expressions)
69 *  Interpreter - Implicit and explicit conversions, GPE method names
70 *  Interpreter - Repair code for return values from predefined names
71 *  Debugger    - Command line input string conversion
72 *  AcpiDump    - ACPI table physical addresses
73 *  AcpiExec    - Support for namespace overrides
74 *
75 * Notes concerning users of these interfaces:
76 *
77 * AcpiGbl_IntegerByteWidth is used to set the 32/64 bit limit for explicit
78 * and implicit conversions. This global must be set to the proper width.
79 * For the core ACPICA code, the width depends on the DSDT version. For the
80 * AcpiUtStrtoul64 interface, all conversions are 64 bits. This interface is
81 * used primarily for iASL, where the default width is 64 bits for all parsers,
82 * but error checking is performed later to flag cases where a 64-bit constant
83 * is wrongly defined in a 32-bit DSDT/SSDT.
84 *
85 * In ACPI, the only place where octal numbers are supported is within
86 * the ASL language itself. This is implemented via the main AcpiUtStrtoul64
87 * interface. According the ACPI specification, there is no ACPI runtime
88 * support (explicit/implicit) for octal string conversions.
89 *
90 ******************************************************************************/
91
92
93/*******************************************************************************
94 *
95 * FUNCTION:    AcpiUtStrtoul64
96 *
97 * PARAMETERS:  String                  - Null terminated input string,
98 *                                        must be a valid pointer
99 *              ReturnValue             - Where the converted integer is
100 *                                        returned. Must be a valid pointer
101 *
102 * RETURN:      Status and converted integer. Returns an exception on a
103 *              64-bit numeric overflow
104 *
105 * DESCRIPTION: Convert a string into an unsigned integer. Always performs a
106 *              full 64-bit conversion, regardless of the current global
107 *              integer width. Supports Decimal, Hex, and Octal strings.
108 *
109 * Current users of this function:
110 *
111 *  iASL        - Preprocessor (constants and math expressions)
112 *  iASL        - Main ASL parser, conversion of ASL constants to integers
113 *  iASL        - Data Table Compiler parser (constants and math expressions)
114 *  Interpreter - Repair code for return values from predefined names
115 *  AcpiDump    - ACPI table physical addresses
116 *  AcpiExec    - Support for namespace overrides
117 *
118 ******************************************************************************/
119
120ACPI_STATUS
121AcpiUtStrtoul64 (
122    char                    *String,
123    UINT64                  *ReturnValue)
124{
125    ACPI_STATUS             Status = AE_OK;
126    UINT8                   OriginalBitWidth;
127    UINT32                  Base = 10;          /* Default is decimal */
128
129
130    ACPI_FUNCTION_TRACE_STR (UtStrtoul64, String);
131
132
133    *ReturnValue = 0;
134
135    /* A NULL return string returns a value of zero */
136
137    if (*String == 0)
138    {
139        return_ACPI_STATUS (AE_OK);
140    }
141
142    if (!AcpiUtRemoveWhitespace (&String))
143    {
144        return_ACPI_STATUS (AE_OK);
145    }
146
147    /*
148     * 1) Check for a hex constant. A "0x" prefix indicates base 16.
149     */
150    if (AcpiUtDetectHexPrefix (&String))
151    {
152        Base = 16;
153    }
154
155    /*
156     * 2) Check for an octal constant, defined to be a leading zero
157     * followed by sequence of octal digits (0-7)
158     */
159    else if (AcpiUtDetectOctalPrefix (&String))
160    {
161        Base = 8;
162    }
163
164    if (!AcpiUtRemoveLeadingZeros (&String))
165    {
166        return_ACPI_STATUS (AE_OK);     /* Return value 0 */
167    }
168
169    /*
170     * Force a full 64-bit conversion. The caller (usually iASL) must
171     * check for a 32-bit overflow later as necessary (If current mode
172     * is 32-bit, meaning a 32-bit DSDT).
173     */
174    OriginalBitWidth = AcpiGbl_IntegerBitWidth;
175    AcpiGbl_IntegerBitWidth = 64;
176
177    /*
178     * Perform the base 8, 10, or 16 conversion. A 64-bit numeric overflow
179     * will return an exception (to allow iASL to flag the statement).
180     */
181    switch (Base)
182    {
183    case 8:
184        Status = AcpiUtConvertOctalString (String, ReturnValue);
185        break;
186
187    case 10:
188        Status = AcpiUtConvertDecimalString (String, ReturnValue);
189        break;
190
191    case 16:
192    default:
193        Status = AcpiUtConvertHexString (String, ReturnValue);
194        break;
195    }
196
197    /* Only possible exception from above is a 64-bit overflow */
198
199    AcpiGbl_IntegerBitWidth = OriginalBitWidth;
200    return_ACPI_STATUS (Status);
201}
202
203
204/*******************************************************************************
205 *
206 * FUNCTION:    AcpiUtImplicitStrtoul64
207 *
208 * PARAMETERS:  String                  - Null terminated input string,
209 *                                        must be a valid pointer
210 *
211 * RETURN:      Converted integer
212 *
213 * DESCRIPTION: Perform a 64-bit conversion with restrictions placed upon
214 *              an "implicit conversion" by the ACPI specification. Used by
215 *              many ASL operators that require an integer operand, and support
216 *              an automatic (implicit) conversion from a string operand
217 *              to the final integer operand. The major restriction is that
218 *              only hex strings are supported.
219 *
220 * -----------------------------------------------------------------------------
221 *
222 * Base is always 16, either with or without the 0x prefix. Decimal and
223 * Octal strings are not supported, as per the ACPI specification.
224 *
225 * Examples (both are hex values):
226 *      Add ("BA98", Arg0, Local0)
227 *      Subtract ("0x12345678", Arg1, Local1)
228 *
229 * Conversion rules as extracted from the ACPI specification:
230 *
231 *  The converted integer is initialized to the value zero.
232 *  The ASCII string is always interpreted as a hexadecimal constant.
233 *
234 *  1)  According to the ACPI specification, a "0x" prefix is not allowed.
235 *      However, ACPICA allows this as an ACPI extension on general
236 *      principle. (NO ERROR)
237 *
238 *  2)  The conversion terminates when the size of an integer is reached
239 *      (32 or 64 bits). There are no numeric overflow conditions. (NO ERROR)
240 *
241 *  3)  The first non-hex character terminates the conversion and returns
242 *      the current accumulated value of the converted integer (NO ERROR).
243 *
244 *  4)  Conversion of a null (zero-length) string to an integer is
245 *      technically not allowed. However, ACPICA allows this as an ACPI
246 *      extension. The conversion returns the value 0. (NO ERROR)
247 *
248 * NOTE: There are no error conditions returned by this function. At
249 * the minimum, a value of zero is returned.
250 *
251 * Current users of this function:
252 *
253 *  Interpreter - All runtime implicit conversions, as per ACPI specification
254 *  iASL        - Data Table Compiler parser (constants and math expressions)
255 *
256 ******************************************************************************/
257
258UINT64
259AcpiUtImplicitStrtoul64 (
260    char                    *String)
261{
262    UINT64                  ConvertedInteger = 0;
263
264
265    ACPI_FUNCTION_TRACE_STR (UtImplicitStrtoul64, String);
266
267
268    if (!AcpiUtRemoveWhitespace (&String))
269    {
270        return_VALUE (0);
271    }
272
273    /*
274     * Per the ACPI specification, only hexadecimal is supported for
275     * implicit conversions, and the "0x" prefix is "not allowed".
276     * However, allow a "0x" prefix as an ACPI extension.
277     */
278    AcpiUtRemoveHexPrefix (&String);
279
280    if (!AcpiUtRemoveLeadingZeros (&String))
281    {
282        return_VALUE (0);
283    }
284
285    /*
286     * Ignore overflow as per the ACPI specification. This is implemented by
287     * ignoring the return status from the conversion function called below.
288     * On overflow, the input string is simply truncated.
289     */
290    AcpiUtConvertHexString (String, &ConvertedInteger);
291    return_VALUE (ConvertedInteger);
292}
293
294
295/*******************************************************************************
296 *
297 * FUNCTION:    AcpiUtExplicitStrtoul64
298 *
299 * PARAMETERS:  String                  - Null terminated input string,
300 *                                        must be a valid pointer
301 *
302 * RETURN:      Converted integer
303 *
304 * DESCRIPTION: Perform a 64-bit conversion with the restrictions placed upon
305 *              an "explicit conversion" by the ACPI specification. The
306 *              main restriction is that only hex and decimal are supported.
307 *
308 * -----------------------------------------------------------------------------
309 *
310 * Base is either 10 (default) or 16 (with 0x prefix). Octal (base 8) strings
311 * are not supported, as per the ACPI specification.
312 *
313 * Examples:
314 *      ToInteger ("1000")      Decimal
315 *      ToInteger ("0xABCD")    Hex
316 *
317 * Conversion rules as extracted from the ACPI specification:
318 *
319 *  1)  The input string is either a decimal or hexadecimal numeric string.
320 *      A hex value must be prefixed by "0x" or it is interpreted as decimal.
321 *
322 *  2)  The value must not exceed the maximum of an integer value
323 *      (32 or 64 bits). The ACPI specification states the behavior is
324 *      "unpredictable", so ACPICA matches the behavior of the implicit
325 *      conversion case. There are no numeric overflow conditions. (NO ERROR)
326 *
327 *  3)  Behavior on the first non-hex character is not defined by the ACPI
328 *      specification (for the ToInteger operator), so ACPICA matches the
329 *      behavior of the implicit conversion case. It terminates the
330 *      conversion and returns the current accumulated value of the converted
331 *      integer. (NO ERROR)
332 *
333 *  4)  Conversion of a null (zero-length) string to an integer is
334 *      technically not allowed. However, ACPICA allows this as an ACPI
335 *      extension. The conversion returns the value 0. (NO ERROR)
336 *
337 * NOTE: There are no error conditions returned by this function. At the
338 * minimum, a value of zero is returned.
339 *
340 * Current users of this function:
341 *
342 *  Interpreter - Runtime ASL ToInteger operator, as per the ACPI specification
343 *
344 ******************************************************************************/
345
346UINT64
347AcpiUtExplicitStrtoul64 (
348    char                    *String)
349{
350    UINT64                  ConvertedInteger = 0;
351    UINT32                  Base = 10;          /* Default is decimal */
352
353
354    ACPI_FUNCTION_TRACE_STR (UtExplicitStrtoul64, String);
355
356
357    if (!AcpiUtRemoveWhitespace (&String))
358    {
359        return_VALUE (0);
360    }
361
362    /*
363     * Only Hex and Decimal are supported, as per the ACPI specification.
364     * A "0x" prefix indicates hex; otherwise decimal is assumed.
365     */
366    if (AcpiUtDetectHexPrefix (&String))
367    {
368        Base = 16;
369    }
370
371    if (!AcpiUtRemoveLeadingZeros (&String))
372    {
373        return_VALUE (0);
374    }
375
376    /*
377     * Ignore overflow as per the ACPI specification. This is implemented by
378     * ignoring the return status from the conversion functions called below.
379     * On overflow, the input string is simply truncated.
380     */
381    switch (Base)
382    {
383    case 10:
384    default:
385        AcpiUtConvertDecimalString (String, &ConvertedInteger);
386        break;
387
388    case 16:
389        AcpiUtConvertHexString (String, &ConvertedInteger);
390        break;
391    }
392
393    return_VALUE (ConvertedInteger);
394}
395