xref: /openbmc/qemu/util/cutils.c (revision c39f95dc)
1 /*
2  * Simple C functions to supplement the C library
3  *
4  * Copyright (c) 2006 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 #include "qemu/osdep.h"
25 #include "qemu-common.h"
26 #include "qemu/host-utils.h"
27 #include <math.h>
28 
29 #include "qemu/sockets.h"
30 #include "qemu/iov.h"
31 #include "net/net.h"
32 #include "qemu/cutils.h"
33 #include "qemu/error-report.h"
34 
35 void strpadcpy(char *buf, int buf_size, const char *str, char pad)
36 {
37     int len = qemu_strnlen(str, buf_size);
38     memcpy(buf, str, len);
39     memset(buf + len, pad, buf_size - len);
40 }
41 
42 void pstrcpy(char *buf, int buf_size, const char *str)
43 {
44     int c;
45     char *q = buf;
46 
47     if (buf_size <= 0)
48         return;
49 
50     for(;;) {
51         c = *str++;
52         if (c == 0 || q >= buf + buf_size - 1)
53             break;
54         *q++ = c;
55     }
56     *q = '\0';
57 }
58 
59 /* strcat and truncate. */
60 char *pstrcat(char *buf, int buf_size, const char *s)
61 {
62     int len;
63     len = strlen(buf);
64     if (len < buf_size)
65         pstrcpy(buf + len, buf_size - len, s);
66     return buf;
67 }
68 
69 int strstart(const char *str, const char *val, const char **ptr)
70 {
71     const char *p, *q;
72     p = str;
73     q = val;
74     while (*q != '\0') {
75         if (*p != *q)
76             return 0;
77         p++;
78         q++;
79     }
80     if (ptr)
81         *ptr = p;
82     return 1;
83 }
84 
85 int stristart(const char *str, const char *val, const char **ptr)
86 {
87     const char *p, *q;
88     p = str;
89     q = val;
90     while (*q != '\0') {
91         if (qemu_toupper(*p) != qemu_toupper(*q))
92             return 0;
93         p++;
94         q++;
95     }
96     if (ptr)
97         *ptr = p;
98     return 1;
99 }
100 
101 /* XXX: use host strnlen if available ? */
102 int qemu_strnlen(const char *s, int max_len)
103 {
104     int i;
105 
106     for(i = 0; i < max_len; i++) {
107         if (s[i] == '\0') {
108             break;
109         }
110     }
111     return i;
112 }
113 
114 char *qemu_strsep(char **input, const char *delim)
115 {
116     char *result = *input;
117     if (result != NULL) {
118         char *p;
119 
120         for (p = result; *p != '\0'; p++) {
121             if (strchr(delim, *p)) {
122                 break;
123             }
124         }
125         if (*p == '\0') {
126             *input = NULL;
127         } else {
128             *p = '\0';
129             *input = p + 1;
130         }
131     }
132     return result;
133 }
134 
135 time_t mktimegm(struct tm *tm)
136 {
137     time_t t;
138     int y = tm->tm_year + 1900, m = tm->tm_mon + 1, d = tm->tm_mday;
139     if (m < 3) {
140         m += 12;
141         y--;
142     }
143     t = 86400ULL * (d + (153 * m - 457) / 5 + 365 * y + y / 4 - y / 100 +
144                  y / 400 - 719469);
145     t += 3600 * tm->tm_hour + 60 * tm->tm_min + tm->tm_sec;
146     return t;
147 }
148 
149 /*
150  * Make sure data goes on disk, but if possible do not bother to
151  * write out the inode just for timestamp updates.
152  *
153  * Unfortunately even in 2009 many operating systems do not support
154  * fdatasync and have to fall back to fsync.
155  */
156 int qemu_fdatasync(int fd)
157 {
158 #ifdef CONFIG_FDATASYNC
159     return fdatasync(fd);
160 #else
161     return fsync(fd);
162 #endif
163 }
164 
165 #ifndef _WIN32
166 /* Sets a specific flag */
167 int fcntl_setfl(int fd, int flag)
168 {
169     int flags;
170 
171     flags = fcntl(fd, F_GETFL);
172     if (flags == -1)
173         return -errno;
174 
175     if (fcntl(fd, F_SETFL, flags | flag) == -1)
176         return -errno;
177 
178     return 0;
179 }
180 #endif
181 
182 static int64_t suffix_mul(char suffix, int64_t unit)
183 {
184     switch (qemu_toupper(suffix)) {
185     case 'B':
186         return 1;
187     case 'K':
188         return unit;
189     case 'M':
190         return unit * unit;
191     case 'G':
192         return unit * unit * unit;
193     case 'T':
194         return unit * unit * unit * unit;
195     case 'P':
196         return unit * unit * unit * unit * unit;
197     case 'E':
198         return unit * unit * unit * unit * unit * unit;
199     }
200     return -1;
201 }
202 
203 /*
204  * Convert string to bytes, allowing either B/b for bytes, K/k for KB,
205  * M/m for MB, G/g for GB or T/t for TB. End pointer will be returned
206  * in *end, if not NULL. Return -ERANGE on overflow, Return -EINVAL on
207  * other error.
208  */
209 static int do_strtosz(const char *nptr, char **end,
210                       const char default_suffix, int64_t unit,
211                       uint64_t *result)
212 {
213     int retval;
214     char *endptr;
215     unsigned char c;
216     int mul_required = 0;
217     double val, mul, integral, fraction;
218 
219     errno = 0;
220     val = strtod(nptr, &endptr);
221     if (isnan(val) || endptr == nptr || errno != 0) {
222         retval = -EINVAL;
223         goto out;
224     }
225     fraction = modf(val, &integral);
226     if (fraction != 0) {
227         mul_required = 1;
228     }
229     c = *endptr;
230     mul = suffix_mul(c, unit);
231     if (mul >= 0) {
232         endptr++;
233     } else {
234         mul = suffix_mul(default_suffix, unit);
235         assert(mul >= 0);
236     }
237     if (mul == 1 && mul_required) {
238         retval = -EINVAL;
239         goto out;
240     }
241     /*
242      * Values >= 0xfffffffffffffc00 overflow uint64_t after their trip
243      * through double (53 bits of precision).
244      */
245     if ((val * mul >= 0xfffffffffffffc00) || val < 0) {
246         retval = -ERANGE;
247         goto out;
248     }
249     *result = val * mul;
250     retval = 0;
251 
252 out:
253     if (end) {
254         *end = endptr;
255     } else if (*endptr) {
256         retval = -EINVAL;
257     }
258 
259     return retval;
260 }
261 
262 int qemu_strtosz(const char *nptr, char **end, uint64_t *result)
263 {
264     return do_strtosz(nptr, end, 'B', 1024, result);
265 }
266 
267 int qemu_strtosz_MiB(const char *nptr, char **end, uint64_t *result)
268 {
269     return do_strtosz(nptr, end, 'M', 1024, result);
270 }
271 
272 int qemu_strtosz_metric(const char *nptr, char **end, uint64_t *result)
273 {
274     return do_strtosz(nptr, end, 'B', 1000, result);
275 }
276 
277 /**
278  * Helper function for error checking after strtol() and the like
279  */
280 static int check_strtox_error(const char *nptr, char *ep,
281                               const char **endptr, int libc_errno)
282 {
283     if (endptr) {
284         *endptr = ep;
285     }
286 
287     /* Turn "no conversion" into an error */
288     if (libc_errno == 0 && ep == nptr) {
289         return -EINVAL;
290     }
291 
292     /* Fail when we're expected to consume the string, but didn't */
293     if (!endptr && *ep) {
294         return -EINVAL;
295     }
296 
297     return -libc_errno;
298 }
299 
300 /**
301  * Convert string @nptr to a long integer, and store it in @result.
302  *
303  * This is a wrapper around strtol() that is harder to misuse.
304  * Semantics of @nptr, @endptr, @base match strtol() with differences
305  * noted below.
306  *
307  * @nptr may be null, and no conversion is performed then.
308  *
309  * If no conversion is performed, store @nptr in *@endptr and return
310  * -EINVAL.
311  *
312  * If @endptr is null, and the string isn't fully converted, return
313  * -EINVAL.  This is the case when the pointer that would be stored in
314  * a non-null @endptr points to a character other than '\0'.
315  *
316  * If the conversion overflows @result, store LONG_MAX in @result,
317  * and return -ERANGE.
318  *
319  * If the conversion underflows @result, store LONG_MIN in @result,
320  * and return -ERANGE.
321  *
322  * Else store the converted value in @result, and return zero.
323  */
324 int qemu_strtol(const char *nptr, const char **endptr, int base,
325                 long *result)
326 {
327     char *ep;
328 
329     if (!nptr) {
330         if (endptr) {
331             *endptr = nptr;
332         }
333         return -EINVAL;
334     }
335 
336     errno = 0;
337     *result = strtol(nptr, &ep, base);
338     return check_strtox_error(nptr, ep, endptr, errno);
339 }
340 
341 /**
342  * Convert string @nptr to an unsigned long, and store it in @result.
343  *
344  * This is a wrapper around strtoul() that is harder to misuse.
345  * Semantics of @nptr, @endptr, @base match strtoul() with differences
346  * noted below.
347  *
348  * @nptr may be null, and no conversion is performed then.
349  *
350  * If no conversion is performed, store @nptr in *@endptr and return
351  * -EINVAL.
352  *
353  * If @endptr is null, and the string isn't fully converted, return
354  * -EINVAL.  This is the case when the pointer that would be stored in
355  * a non-null @endptr points to a character other than '\0'.
356  *
357  * If the conversion overflows @result, store ULONG_MAX in @result,
358  * and return -ERANGE.
359  *
360  * Else store the converted value in @result, and return zero.
361  *
362  * Note that a number with a leading minus sign gets converted without
363  * the minus sign, checked for overflow (see above), then negated (in
364  * @result's type).  This is exactly how strtoul() works.
365  */
366 int qemu_strtoul(const char *nptr, const char **endptr, int base,
367                  unsigned long *result)
368 {
369     char *ep;
370 
371     if (!nptr) {
372         if (endptr) {
373             *endptr = nptr;
374         }
375         return -EINVAL;
376     }
377 
378     errno = 0;
379     *result = strtoul(nptr, &ep, base);
380     /* Windows returns 1 for negative out-of-range values.  */
381     if (errno == ERANGE) {
382         *result = -1;
383     }
384     return check_strtox_error(nptr, ep, endptr, errno);
385 }
386 
387 /**
388  * Convert string @nptr to an int64_t.
389  *
390  * Works like qemu_strtol(), except it stores INT64_MAX on overflow,
391  * and INT_MIN on underflow.
392  */
393 int qemu_strtoi64(const char *nptr, const char **endptr, int base,
394                  int64_t *result)
395 {
396     char *ep;
397 
398     if (!nptr) {
399         if (endptr) {
400             *endptr = nptr;
401         }
402         return -EINVAL;
403     }
404 
405     errno = 0;
406     /* FIXME This assumes int64_t is long long */
407     *result = strtoll(nptr, &ep, base);
408     return check_strtox_error(nptr, ep, endptr, errno);
409 }
410 
411 /**
412  * Convert string @nptr to an uint64_t.
413  *
414  * Works like qemu_strtoul(), except it stores UINT64_MAX on overflow.
415  */
416 int qemu_strtou64(const char *nptr, const char **endptr, int base,
417                   uint64_t *result)
418 {
419     char *ep;
420 
421     if (!nptr) {
422         if (endptr) {
423             *endptr = nptr;
424         }
425         return -EINVAL;
426     }
427 
428     errno = 0;
429     /* FIXME This assumes uint64_t is unsigned long long */
430     *result = strtoull(nptr, &ep, base);
431     /* Windows returns 1 for negative out-of-range values.  */
432     if (errno == ERANGE) {
433         *result = -1;
434     }
435     return check_strtox_error(nptr, ep, endptr, errno);
436 }
437 
438 /**
439  * parse_uint:
440  *
441  * @s: String to parse
442  * @value: Destination for parsed integer value
443  * @endptr: Destination for pointer to first character not consumed
444  * @base: integer base, between 2 and 36 inclusive, or 0
445  *
446  * Parse unsigned integer
447  *
448  * Parsed syntax is like strtoull()'s: arbitrary whitespace, a single optional
449  * '+' or '-', an optional "0x" if @base is 0 or 16, one or more digits.
450  *
451  * If @s is null, or @base is invalid, or @s doesn't start with an
452  * integer in the syntax above, set *@value to 0, *@endptr to @s, and
453  * return -EINVAL.
454  *
455  * Set *@endptr to point right beyond the parsed integer (even if the integer
456  * overflows or is negative, all digits will be parsed and *@endptr will
457  * point right beyond them).
458  *
459  * If the integer is negative, set *@value to 0, and return -ERANGE.
460  *
461  * If the integer overflows unsigned long long, set *@value to
462  * ULLONG_MAX, and return -ERANGE.
463  *
464  * Else, set *@value to the parsed integer, and return 0.
465  */
466 int parse_uint(const char *s, unsigned long long *value, char **endptr,
467                int base)
468 {
469     int r = 0;
470     char *endp = (char *)s;
471     unsigned long long val = 0;
472 
473     if (!s) {
474         r = -EINVAL;
475         goto out;
476     }
477 
478     errno = 0;
479     val = strtoull(s, &endp, base);
480     if (errno) {
481         r = -errno;
482         goto out;
483     }
484 
485     if (endp == s) {
486         r = -EINVAL;
487         goto out;
488     }
489 
490     /* make sure we reject negative numbers: */
491     while (isspace((unsigned char)*s)) {
492         s++;
493     }
494     if (*s == '-') {
495         val = 0;
496         r = -ERANGE;
497         goto out;
498     }
499 
500 out:
501     *value = val;
502     *endptr = endp;
503     return r;
504 }
505 
506 /**
507  * parse_uint_full:
508  *
509  * @s: String to parse
510  * @value: Destination for parsed integer value
511  * @base: integer base, between 2 and 36 inclusive, or 0
512  *
513  * Parse unsigned integer from entire string
514  *
515  * Have the same behavior of parse_uint(), but with an additional check
516  * for additional data after the parsed number. If extra characters are present
517  * after the parsed number, the function will return -EINVAL, and *@v will
518  * be set to 0.
519  */
520 int parse_uint_full(const char *s, unsigned long long *value, int base)
521 {
522     char *endp;
523     int r;
524 
525     r = parse_uint(s, value, &endp, base);
526     if (r < 0) {
527         return r;
528     }
529     if (*endp) {
530         *value = 0;
531         return -EINVAL;
532     }
533 
534     return 0;
535 }
536 
537 int qemu_parse_fd(const char *param)
538 {
539     long fd;
540     char *endptr;
541 
542     errno = 0;
543     fd = strtol(param, &endptr, 10);
544     if (param == endptr /* no conversion performed */                    ||
545         errno != 0      /* not representable as long; possibly others */ ||
546         *endptr != '\0' /* final string not empty */                     ||
547         fd < 0          /* invalid as file descriptor */                 ||
548         fd > INT_MAX    /* not representable as int */) {
549         return -1;
550     }
551     return fd;
552 }
553 
554 /*
555  * Implementation of  ULEB128 (http://en.wikipedia.org/wiki/LEB128)
556  * Input is limited to 14-bit numbers
557  */
558 int uleb128_encode_small(uint8_t *out, uint32_t n)
559 {
560     g_assert(n <= 0x3fff);
561     if (n < 0x80) {
562         *out++ = n;
563         return 1;
564     } else {
565         *out++ = (n & 0x7f) | 0x80;
566         *out++ = n >> 7;
567         return 2;
568     }
569 }
570 
571 int uleb128_decode_small(const uint8_t *in, uint32_t *n)
572 {
573     if (!(*in & 0x80)) {
574         *n = *in++;
575         return 1;
576     } else {
577         *n = *in++ & 0x7f;
578         /* we exceed 14 bit number */
579         if (*in & 0x80) {
580             return -1;
581         }
582         *n |= *in++ << 7;
583         return 2;
584     }
585 }
586 
587 /*
588  * helper to parse debug environment variables
589  */
590 int parse_debug_env(const char *name, int max, int initial)
591 {
592     char *debug_env = getenv(name);
593     char *inv = NULL;
594     long debug;
595 
596     if (!debug_env) {
597         return initial;
598     }
599     errno = 0;
600     debug = strtol(debug_env, &inv, 10);
601     if (inv == debug_env) {
602         return initial;
603     }
604     if (debug < 0 || debug > max || errno != 0) {
605         warn_report("%s not in [0, %d]", name, max);
606         return initial;
607     }
608     return debug;
609 }
610 
611 /*
612  * Helper to print ethernet mac address
613  */
614 const char *qemu_ether_ntoa(const MACAddr *mac)
615 {
616     static char ret[18];
617 
618     snprintf(ret, sizeof(ret), "%02x:%02x:%02x:%02x:%02x:%02x",
619              mac->a[0], mac->a[1], mac->a[2], mac->a[3], mac->a[4], mac->a[5]);
620 
621     return ret;
622 }
623 
624 /*
625  * Return human readable string for size @val.
626  * @val can be anything that uint64_t allows (no more than "16 EiB").
627  * Use IEC binary units like KiB, MiB, and so forth.
628  * Caller is responsible for passing it to g_free().
629  */
630 char *size_to_str(uint64_t val)
631 {
632     static const char *suffixes[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi", "Ei" };
633     unsigned long div;
634     int i;
635 
636     /*
637      * The exponent (returned in i) minus one gives us
638      * floor(log2(val * 1024 / 1000).  The correction makes us
639      * switch to the higher power when the integer part is >= 1000.
640      * (see e41b509d68afb1f for more info)
641      */
642     frexp(val / (1000.0 / 1024.0), &i);
643     i = (i - 1) / 10;
644     div = 1ULL << (i * 10);
645 
646     return g_strdup_printf("%0.3g %sB", (double)val / div, suffixes[i]);
647 }
648