xref: /openbmc/linux/tools/perf/util/string.c (revision e2c75e76)
1 // SPDX-License-Identifier: GPL-2.0
2 #include "string2.h"
3 #include <linux/kernel.h>
4 #include <linux/string.h>
5 #include <stdlib.h>
6 
7 #include "sane_ctype.h"
8 
9 #define K 1024LL
10 /*
11  * perf_atoll()
12  * Parse (\d+)(b|B|kb|KB|mb|MB|gb|GB|tb|TB) (e.g. "256MB")
13  * and return its numeric value
14  */
15 s64 perf_atoll(const char *str)
16 {
17 	s64 length;
18 	char *p;
19 	char c;
20 
21 	if (!isdigit(str[0]))
22 		goto out_err;
23 
24 	length = strtoll(str, &p, 10);
25 	switch (c = *p++) {
26 		case 'b': case 'B':
27 			if (*p)
28 				goto out_err;
29 
30 			__fallthrough;
31 		case '\0':
32 			return length;
33 		default:
34 			goto out_err;
35 		/* two-letter suffices */
36 		case 'k': case 'K':
37 			length <<= 10;
38 			break;
39 		case 'm': case 'M':
40 			length <<= 20;
41 			break;
42 		case 'g': case 'G':
43 			length <<= 30;
44 			break;
45 		case 't': case 'T':
46 			length <<= 40;
47 			break;
48 	}
49 	/* we want the cases to match */
50 	if (islower(c)) {
51 		if (strcmp(p, "b") != 0)
52 			goto out_err;
53 	} else {
54 		if (strcmp(p, "B") != 0)
55 			goto out_err;
56 	}
57 	return length;
58 
59 out_err:
60 	return -1;
61 }
62 
63 /*
64  * Helper function for splitting a string into an argv-like array.
65  * originally copied from lib/argv_split.c
66  */
67 static const char *skip_sep(const char *cp)
68 {
69 	while (*cp && isspace(*cp))
70 		cp++;
71 
72 	return cp;
73 }
74 
75 static const char *skip_arg(const char *cp)
76 {
77 	while (*cp && !isspace(*cp))
78 		cp++;
79 
80 	return cp;
81 }
82 
83 static int count_argc(const char *str)
84 {
85 	int count = 0;
86 
87 	while (*str) {
88 		str = skip_sep(str);
89 		if (*str) {
90 			count++;
91 			str = skip_arg(str);
92 		}
93 	}
94 
95 	return count;
96 }
97 
98 /**
99  * argv_free - free an argv
100  * @argv - the argument vector to be freed
101  *
102  * Frees an argv and the strings it points to.
103  */
104 void argv_free(char **argv)
105 {
106 	char **p;
107 	for (p = argv; *p; p++) {
108 		free(*p);
109 		*p = NULL;
110 	}
111 
112 	free(argv);
113 }
114 
115 /**
116  * argv_split - split a string at whitespace, returning an argv
117  * @str: the string to be split
118  * @argcp: returned argument count
119  *
120  * Returns an array of pointers to strings which are split out from
121  * @str.  This is performed by strictly splitting on white-space; no
122  * quote processing is performed.  Multiple whitespace characters are
123  * considered to be a single argument separator.  The returned array
124  * is always NULL-terminated.  Returns NULL on memory allocation
125  * failure.
126  */
127 char **argv_split(const char *str, int *argcp)
128 {
129 	int argc = count_argc(str);
130 	char **argv = calloc(argc + 1, sizeof(*argv));
131 	char **argvp;
132 
133 	if (argv == NULL)
134 		goto out;
135 
136 	if (argcp)
137 		*argcp = argc;
138 
139 	argvp = argv;
140 
141 	while (*str) {
142 		str = skip_sep(str);
143 
144 		if (*str) {
145 			const char *p = str;
146 			char *t;
147 
148 			str = skip_arg(str);
149 
150 			t = strndup(p, str-p);
151 			if (t == NULL)
152 				goto fail;
153 			*argvp++ = t;
154 		}
155 	}
156 	*argvp = NULL;
157 
158 out:
159 	return argv;
160 
161 fail:
162 	argv_free(argv);
163 	return NULL;
164 }
165 
166 /* Character class matching */
167 static bool __match_charclass(const char *pat, char c, const char **npat)
168 {
169 	bool complement = false, ret = true;
170 
171 	if (*pat == '!') {
172 		complement = true;
173 		pat++;
174 	}
175 	if (*pat++ == c)	/* First character is special */
176 		goto end;
177 
178 	while (*pat && *pat != ']') {	/* Matching */
179 		if (*pat == '-' && *(pat + 1) != ']') {	/* Range */
180 			if (*(pat - 1) <= c && c <= *(pat + 1))
181 				goto end;
182 			if (*(pat - 1) > *(pat + 1))
183 				goto error;
184 			pat += 2;
185 		} else if (*pat++ == c)
186 			goto end;
187 	}
188 	if (!*pat)
189 		goto error;
190 	ret = false;
191 
192 end:
193 	while (*pat && *pat != ']')	/* Searching closing */
194 		pat++;
195 	if (!*pat)
196 		goto error;
197 	*npat = pat + 1;
198 	return complement ? !ret : ret;
199 
200 error:
201 	return false;
202 }
203 
204 /* Glob/lazy pattern matching */
205 static bool __match_glob(const char *str, const char *pat, bool ignore_space,
206 			bool case_ins)
207 {
208 	while (*str && *pat && *pat != '*') {
209 		if (ignore_space) {
210 			/* Ignore spaces for lazy matching */
211 			if (isspace(*str)) {
212 				str++;
213 				continue;
214 			}
215 			if (isspace(*pat)) {
216 				pat++;
217 				continue;
218 			}
219 		}
220 		if (*pat == '?') {	/* Matches any single character */
221 			str++;
222 			pat++;
223 			continue;
224 		} else if (*pat == '[')	/* Character classes/Ranges */
225 			if (__match_charclass(pat + 1, *str, &pat)) {
226 				str++;
227 				continue;
228 			} else
229 				return false;
230 		else if (*pat == '\\') /* Escaped char match as normal char */
231 			pat++;
232 		if (case_ins) {
233 			if (tolower(*str) != tolower(*pat))
234 				return false;
235 		} else if (*str != *pat)
236 			return false;
237 		str++;
238 		pat++;
239 	}
240 	/* Check wild card */
241 	if (*pat == '*') {
242 		while (*pat == '*')
243 			pat++;
244 		if (!*pat)	/* Tail wild card matches all */
245 			return true;
246 		while (*str)
247 			if (__match_glob(str++, pat, ignore_space, case_ins))
248 				return true;
249 	}
250 	return !*str && !*pat;
251 }
252 
253 /**
254  * strglobmatch - glob expression pattern matching
255  * @str: the target string to match
256  * @pat: the pattern string to match
257  *
258  * This returns true if the @str matches @pat. @pat can includes wildcards
259  * ('*','?') and character classes ([CHARS], complementation and ranges are
260  * also supported). Also, this supports escape character ('\') to use special
261  * characters as normal character.
262  *
263  * Note: if @pat syntax is broken, this always returns false.
264  */
265 bool strglobmatch(const char *str, const char *pat)
266 {
267 	return __match_glob(str, pat, false, false);
268 }
269 
270 bool strglobmatch_nocase(const char *str, const char *pat)
271 {
272 	return __match_glob(str, pat, false, true);
273 }
274 
275 /**
276  * strlazymatch - matching pattern strings lazily with glob pattern
277  * @str: the target string to match
278  * @pat: the pattern string to match
279  *
280  * This is similar to strglobmatch, except this ignores spaces in
281  * the target string.
282  */
283 bool strlazymatch(const char *str, const char *pat)
284 {
285 	return __match_glob(str, pat, true, false);
286 }
287 
288 /**
289  * strtailcmp - Compare the tail of two strings
290  * @s1: 1st string to be compared
291  * @s2: 2nd string to be compared
292  *
293  * Return 0 if whole of either string is same as another's tail part.
294  */
295 int strtailcmp(const char *s1, const char *s2)
296 {
297 	int i1 = strlen(s1);
298 	int i2 = strlen(s2);
299 	while (--i1 >= 0 && --i2 >= 0) {
300 		if (s1[i1] != s2[i2])
301 			return s1[i1] - s2[i2];
302 	}
303 	return 0;
304 }
305 
306 /**
307  * strxfrchar - Locate and replace character in @s
308  * @s:    The string to be searched/changed.
309  * @from: Source character to be replaced.
310  * @to:   Destination character.
311  *
312  * Return pointer to the changed string.
313  */
314 char *strxfrchar(char *s, char from, char to)
315 {
316 	char *p = s;
317 
318 	while ((p = strchr(p, from)) != NULL)
319 		*p++ = to;
320 
321 	return s;
322 }
323 
324 /**
325  * ltrim - Removes leading whitespace from @s.
326  * @s: The string to be stripped.
327  *
328  * Return pointer to the first non-whitespace character in @s.
329  */
330 char *ltrim(char *s)
331 {
332 	while (isspace(*s))
333 		s++;
334 
335 	return s;
336 }
337 
338 /**
339  * rtrim - Removes trailing whitespace from @s.
340  * @s: The string to be stripped.
341  *
342  * Note that the first trailing whitespace is replaced with a %NUL-terminator
343  * in the given string @s. Returns @s.
344  */
345 char *rtrim(char *s)
346 {
347 	size_t size = strlen(s);
348 	char *end;
349 
350 	if (!size)
351 		return s;
352 
353 	end = s + size - 1;
354 	while (end >= s && isspace(*end))
355 		end--;
356 	*(end + 1) = '\0';
357 
358 	return s;
359 }
360 
361 char *asprintf_expr_inout_ints(const char *var, bool in, size_t nints, int *ints)
362 {
363 	/*
364 	 * FIXME: replace this with an expression using log10() when we
365 	 * find a suitable implementation, maybe the one in the dvb drivers...
366 	 *
367 	 * "%s == %d || " = log10(MAXINT) * 2 + 8 chars for the operators
368 	 */
369 	size_t size = nints * 28 + 1; /* \0 */
370 	size_t i, printed = 0;
371 	char *expr = malloc(size);
372 
373 	if (expr) {
374 		const char *or_and = "||", *eq_neq = "==";
375 		char *e = expr;
376 
377 		if (!in) {
378 			or_and = "&&";
379 			eq_neq = "!=";
380 		}
381 
382 		for (i = 0; i < nints; ++i) {
383 			if (printed == size)
384 				goto out_err_overflow;
385 
386 			if (i > 0)
387 				printed += scnprintf(e + printed, size - printed, " %s ", or_and);
388 			printed += scnprintf(e + printed, size - printed,
389 					     "%s %s %d", var, eq_neq, ints[i]);
390 		}
391 	}
392 
393 	return expr;
394 
395 out_err_overflow:
396 	free(expr);
397 	return NULL;
398 }
399 
400 /* Like strpbrk(), but not break if it is right after a backslash (escaped) */
401 char *strpbrk_esc(char *str, const char *stopset)
402 {
403 	char *ptr;
404 
405 	do {
406 		ptr = strpbrk(str, stopset);
407 		if (ptr == str ||
408 		    (ptr == str + 1 && *(ptr - 1) != '\\'))
409 			break;
410 		str = ptr + 1;
411 	} while (ptr && *(ptr - 1) == '\\' && *(ptr - 2) != '\\');
412 
413 	return ptr;
414 }
415 
416 /* Like strdup, but do not copy a single backslash */
417 char *strdup_esc(const char *str)
418 {
419 	char *s, *d, *p, *ret = strdup(str);
420 
421 	if (!ret)
422 		return NULL;
423 
424 	d = strchr(ret, '\\');
425 	if (!d)
426 		return ret;
427 
428 	s = d + 1;
429 	do {
430 		if (*s == '\0') {
431 			*d = '\0';
432 			break;
433 		}
434 		p = strchr(s + 1, '\\');
435 		if (p) {
436 			memmove(d, s, p - s);
437 			d += p - s;
438 			s = p + 1;
439 		} else
440 			memmove(d, s, strlen(s) + 1);
441 	} while (p);
442 
443 	return ret;
444 }
445