xref: /linux/drivers/acpi/acpica/utnonansi.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*******************************************************************************
2  *
3  * Module Name: utnonansi - Non-ansi C library functions
4  *
5  ******************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2015, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 
47 #define _COMPONENT          ACPI_UTILITIES
48 ACPI_MODULE_NAME("utnonansi")
49 
50 /*
51  * Non-ANSI C library functions - strlwr, strupr, stricmp, and a 64-bit
52  * version of strtoul.
53  */
54 /*******************************************************************************
55  *
56  * FUNCTION:    acpi_ut_strlwr (strlwr)
57  *
58  * PARAMETERS:  src_string      - The source string to convert
59  *
60  * RETURN:      None
61  *
62  * DESCRIPTION: Convert a string to lowercase
63  *
64  ******************************************************************************/
65 void acpi_ut_strlwr(char *src_string)
66 {
67 	char *string;
68 
69 	ACPI_FUNCTION_ENTRY();
70 
71 	if (!src_string) {
72 		return;
73 	}
74 
75 	/* Walk entire string, lowercasing the letters */
76 
77 	for (string = src_string; *string; string++) {
78 		*string = (char)tolower((int)*string);
79 	}
80 }
81 
82 /*******************************************************************************
83  *
84  * FUNCTION:    acpi_ut_strupr (strupr)
85  *
86  * PARAMETERS:  src_string      - The source string to convert
87  *
88  * RETURN:      None
89  *
90  * DESCRIPTION: Convert a string to uppercase
91  *
92  ******************************************************************************/
93 
94 void acpi_ut_strupr(char *src_string)
95 {
96 	char *string;
97 
98 	ACPI_FUNCTION_ENTRY();
99 
100 	if (!src_string) {
101 		return;
102 	}
103 
104 	/* Walk entire string, uppercasing the letters */
105 
106 	for (string = src_string; *string; string++) {
107 		*string = (char)toupper((int)*string);
108 	}
109 }
110 
111 /******************************************************************************
112  *
113  * FUNCTION:    acpi_ut_stricmp (stricmp)
114  *
115  * PARAMETERS:  string1             - first string to compare
116  *              string2             - second string to compare
117  *
118  * RETURN:      int that signifies string relationship. Zero means strings
119  *              are equal.
120  *
121  * DESCRIPTION: Case-insensitive string compare. Implementation of the
122  *              non-ANSI stricmp function.
123  *
124  ******************************************************************************/
125 
126 int acpi_ut_stricmp(char *string1, char *string2)
127 {
128 	int c1;
129 	int c2;
130 
131 	do {
132 		c1 = tolower((int)*string1);
133 		c2 = tolower((int)*string2);
134 
135 		string1++;
136 		string2++;
137 	}
138 	while ((c1 == c2) && (c1));
139 
140 	return (c1 - c2);
141 }
142 
143 /*******************************************************************************
144  *
145  * FUNCTION:    acpi_ut_strtoul64
146  *
147  * PARAMETERS:  string          - Null terminated string
148  *              base            - Radix of the string: 16 or ACPI_ANY_BASE;
149  *                                ACPI_ANY_BASE means 'in behalf of to_integer'
150  *              ret_integer     - Where the converted integer is returned
151  *
152  * RETURN:      Status and Converted value
153  *
154  * DESCRIPTION: Convert a string into an unsigned value. Performs either a
155  *              32-bit or 64-bit conversion, depending on the current mode
156  *              of the interpreter.
157  *
158  * NOTE:        Does not support Octal strings, not needed.
159  *
160  ******************************************************************************/
161 
162 acpi_status acpi_ut_strtoul64(char *string, u32 base, u64 *ret_integer)
163 {
164 	u32 this_digit = 0;
165 	u64 return_value = 0;
166 	u64 quotient;
167 	u64 dividend;
168 	u32 to_integer_op = (base == ACPI_ANY_BASE);
169 	u32 mode32 = (acpi_gbl_integer_byte_width == 4);
170 	u8 valid_digits = 0;
171 	u8 sign_of0x = 0;
172 	u8 term = 0;
173 
174 	ACPI_FUNCTION_TRACE_STR(ut_stroul64, string);
175 
176 	switch (base) {
177 	case ACPI_ANY_BASE:
178 	case 16:
179 
180 		break;
181 
182 	default:
183 
184 		/* Invalid Base */
185 
186 		return_ACPI_STATUS(AE_BAD_PARAMETER);
187 	}
188 
189 	if (!string) {
190 		goto error_exit;
191 	}
192 
193 	/* Skip over any white space in the buffer */
194 
195 	while ((*string) && (isspace((int)*string) || *string == '\t')) {
196 		string++;
197 	}
198 
199 	if (to_integer_op) {
200 		/*
201 		 * Base equal to ACPI_ANY_BASE means 'ToInteger operation case'.
202 		 * We need to determine if it is decimal or hexadecimal.
203 		 */
204 		if ((*string == '0') && (tolower((int)*(string + 1)) == 'x')) {
205 			sign_of0x = 1;
206 			base = 16;
207 
208 			/* Skip over the leading '0x' */
209 			string += 2;
210 		} else {
211 			base = 10;
212 		}
213 	}
214 
215 	/* Any string left? Check that '0x' is not followed by white space. */
216 
217 	if (!(*string) || isspace((int)*string) || *string == '\t') {
218 		if (to_integer_op) {
219 			goto error_exit;
220 		} else {
221 			goto all_done;
222 		}
223 	}
224 
225 	/*
226 	 * Perform a 32-bit or 64-bit conversion, depending upon the current
227 	 * execution mode of the interpreter
228 	 */
229 	dividend = (mode32) ? ACPI_UINT32_MAX : ACPI_UINT64_MAX;
230 
231 	/* Main loop: convert the string to a 32- or 64-bit integer */
232 
233 	while (*string) {
234 		if (isdigit((int)*string)) {
235 
236 			/* Convert ASCII 0-9 to Decimal value */
237 
238 			this_digit = ((u8)*string) - '0';
239 		} else if (base == 10) {
240 
241 			/* Digit is out of range; possible in to_integer case only */
242 
243 			term = 1;
244 		} else {
245 			this_digit = (u8)toupper((int)*string);
246 			if (isxdigit((int)this_digit)) {
247 
248 				/* Convert ASCII Hex char to value */
249 
250 				this_digit = this_digit - 'A' + 10;
251 			} else {
252 				term = 1;
253 			}
254 		}
255 
256 		if (term) {
257 			if (to_integer_op) {
258 				goto error_exit;
259 			} else {
260 				break;
261 			}
262 		} else if ((valid_digits == 0) && (this_digit == 0)
263 			   && !sign_of0x) {
264 
265 			/* Skip zeros */
266 			string++;
267 			continue;
268 		}
269 
270 		valid_digits++;
271 
272 		if (sign_of0x
273 		    && ((valid_digits > 16)
274 			|| ((valid_digits > 8) && mode32))) {
275 			/*
276 			 * This is to_integer operation case.
277 			 * No any restrictions for string-to-integer conversion,
278 			 * see ACPI spec.
279 			 */
280 			goto error_exit;
281 		}
282 
283 		/* Divide the digit into the correct position */
284 
285 		(void)acpi_ut_short_divide((dividend - (u64)this_digit),
286 					   base, &quotient, NULL);
287 
288 		if (return_value > quotient) {
289 			if (to_integer_op) {
290 				goto error_exit;
291 			} else {
292 				break;
293 			}
294 		}
295 
296 		return_value *= base;
297 		return_value += this_digit;
298 		string++;
299 	}
300 
301 	/* All done, normal exit */
302 
303 all_done:
304 
305 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Converted value: %8.8X%8.8X\n",
306 			  ACPI_FORMAT_UINT64(return_value)));
307 
308 	*ret_integer = return_value;
309 	return_ACPI_STATUS(AE_OK);
310 
311 error_exit:
312 	/* Base was set/validated above */
313 
314 	if (base == 10) {
315 		return_ACPI_STATUS(AE_BAD_DECIMAL_CONSTANT);
316 	} else {
317 		return_ACPI_STATUS(AE_BAD_HEX_CONSTANT);
318 	}
319 }
320 
321 #if defined (ACPI_DEBUGGER) || defined (ACPI_APPLICATION)
322 /*******************************************************************************
323  *
324  * FUNCTION:    acpi_ut_safe_strcpy, acpi_ut_safe_strcat, acpi_ut_safe_strncat
325  *
326  * PARAMETERS:  Adds a "DestSize" parameter to each of the standard string
327  *              functions. This is the size of the Destination buffer.
328  *
329  * RETURN:      TRUE if the operation would overflow the destination buffer.
330  *
331  * DESCRIPTION: Safe versions of standard Clib string functions. Ensure that
332  *              the result of the operation will not overflow the output string
333  *              buffer.
334  *
335  * NOTE:        These functions are typically only helpful for processing
336  *              user input and command lines. For most ACPICA code, the
337  *              required buffer length is precisely calculated before buffer
338  *              allocation, so the use of these functions is unnecessary.
339  *
340  ******************************************************************************/
341 
342 u8 acpi_ut_safe_strcpy(char *dest, acpi_size dest_size, char *source)
343 {
344 
345 	if (strlen(source) >= dest_size) {
346 		return (TRUE);
347 	}
348 
349 	strcpy(dest, source);
350 	return (FALSE);
351 }
352 
353 u8 acpi_ut_safe_strcat(char *dest, acpi_size dest_size, char *source)
354 {
355 
356 	if ((strlen(dest) + strlen(source)) >= dest_size) {
357 		return (TRUE);
358 	}
359 
360 	strcat(dest, source);
361 	return (FALSE);
362 }
363 
364 u8
365 acpi_ut_safe_strncat(char *dest,
366 		     acpi_size dest_size,
367 		     char *source, acpi_size max_transfer_length)
368 {
369 	acpi_size actual_transfer_length;
370 
371 	actual_transfer_length = ACPI_MIN(max_transfer_length, strlen(source));
372 
373 	if ((strlen(dest) + actual_transfer_length) >= dest_size) {
374 		return (TRUE);
375 	}
376 
377 	strncat(dest, source, max_transfer_length);
378 	return (FALSE);
379 }
380 #endif
381