summaryrefslogtreecommitdiffstats
path: root/contrib/qemu/util/cutils.c
blob: 6caa4b8ddc4b38a96095f835a24ab3e14d075b55 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
/*
 * Simple C functions to supplement the C library
 *
 * Copyright (c) 2006 Fabrice Bellard
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include "qemu-common.h"
#include "qemu/host-utils.h"
#include <math.h>

#include "qemu/sockets.h"
#include "qemu/iov.h"

void strpadcpy(char *buf, int buf_size, const char *str, char pad)
{
    int len = qemu_strnlen(str, buf_size);
    memcpy(buf, str, len);
    memset(buf + len, pad, buf_size - len);
}

void pstrcpy(char *buf, int buf_size, const char *str)
{
    int c;
    char *q = buf;

    if (buf_size <= 0)
        return;

    for(;;) {
        c = *str++;
        if (c == 0 || q >= buf + buf_size - 1)
            break;
        *q++ = c;
    }
    *q = '\0';
}

/* strcat and truncate. */
char *pstrcat(char *buf, int buf_size, const char *s)
{
    int len;
    len = strlen(buf);
    if (len < buf_size)
        pstrcpy(buf + len, buf_size - len, s);
    return buf;
}

int strstart(const char *str, const char *val, const char **ptr)
{
    const char *p, *q;
    p = str;
    q = val;
    while (*q != '\0') {
        if (*p != *q)
            return 0;
        p++;
        q++;
    }
    if (ptr)
        *ptr = p;
    return 1;
}

int stristart(const char *str, const char *val, const char **ptr)
{
    const char *p, *q;
    p = str;
    q = val;
    while (*q != '\0') {
        if (qemu_toupper(*p) != qemu_toupper(*q))
            return 0;
        p++;
        q++;
    }
    if (ptr)
        *ptr = p;
    return 1;
}

/* XXX: use host strnlen if available ? */
int qemu_strnlen(const char *s, int max_len)
{
    int i;

    for(i = 0; i < max_len; i++) {
        if (s[i] == '\0') {
            break;
        }
    }
    return i;
}

char *qemu_strsep(char **input, const char *delim)
{
    char *result = *input;
    if (result != NULL) {
        char *p;

        for (p = result; *p != '\0'; p++) {
            if (strchr(delim, *p)) {
                break;
            }
        }
        if (*p == '\0') {
            *input = NULL;
        } else {
            *p = '\0';
            *input = p + 1;
        }
    }
    return result;
}

time_t mktimegm(struct tm *tm)
{
    time_t t;
    int y = tm->tm_year + 1900, m = tm->tm_mon + 1, d = tm->tm_mday;
    if (m < 3) {
        m += 12;
        y--;
    }
    t = 86400ULL * (d + (153 * m - 457) / 5 + 365 * y + y / 4 - y / 100 + 
                 y / 400 - 719469);
    t += 3600 * tm->tm_hour + 60 * tm->tm_min + tm->tm_sec;
    return t;
}

int qemu_fls(int i)
{
    return 32 - clz32(i);
}

/*
 * Make sure data goes on disk, but if possible do not bother to
 * write out the inode just for timestamp updates.
 *
 * Unfortunately even in 2009 many operating systems do not support
 * fdatasync and have to fall back to fsync.
 */
int qemu_fdatasync(int fd)
{
#ifdef HAVE_FDATASYNC
    return fdatasync(fd);
#else
    return fsync(fd);
#endif
}

/*
 * Searches for an area with non-zero content in a buffer
 *
 * Attention! The len must be a multiple of
 * BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR * sizeof(VECTYPE)
 * and addr must be a multiple of sizeof(VECTYPE) due to
 * restriction of optimizations in this function.
 *
 * can_use_buffer_find_nonzero_offset() can be used to check
 * these requirements.
 *
 * The return value is the offset of the non-zero area rounded
 * down to a multiple of sizeof(VECTYPE) for the first
 * BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR chunks and down to
 * BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR * sizeof(VECTYPE)
 * afterwards.
 *
 * If the buffer is all zero the return value is equal to len.
 */

size_t buffer_find_nonzero_offset(const void *buf, size_t len)
{
    const VECTYPE *p = buf;
    const VECTYPE zero = (VECTYPE){0};
    size_t i;

    assert(can_use_buffer_find_nonzero_offset(buf, len));

    if (!len) {
        return 0;
    }

    for (i = 0; i < BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR; i++) {
        if (!ALL_EQ(p[i], zero)) {
            return i * sizeof(VECTYPE);
        }
    }

    for (i = BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR;
         i < len / sizeof(VECTYPE);
         i += BUFFER_FIND_NONZERO_OFFSET_UNROLL_FACTOR) {
        VECTYPE tmp0 = p[i + 0] | p[i + 1];
        VECTYPE tmp1 = p[i + 2] | p[i + 3];
        VECTYPE tmp2 = p[i + 4] | p[i + 5];
        VECTYPE tmp3 = p[i + 6] | p[i + 7];
        VECTYPE tmp01 = tmp0 | tmp1;
        VECTYPE tmp23 = tmp2 | tmp3;
        if (!ALL_EQ(tmp01 | tmp23, zero)) {
            break;
        }
    }

    return i * sizeof(VECTYPE);
}

/*
 * Checks if a buffer is all zeroes
 *
 * Attention! The len must be a multiple of 4 * sizeof(long) due to
 * restriction of optimizations in this function.
 */
bool buffer_is_zero(const void *buf, size_t len)
{
    /*
     * Use long as the biggest available internal data type that fits into the
     * CPU register and unroll the loop to smooth out the effect of memory
     * latency.
     */

    size_t i;
    long d0, d1, d2, d3;
    const long * const data = buf;

    /* use vector optimized zero check if possible */
    if (can_use_buffer_find_nonzero_offset(buf, len)) {
        return buffer_find_nonzero_offset(buf, len) == len;
    }

    assert(len % (4 * sizeof(long)) == 0);
    len /= sizeof(long);

    for (i = 0; i < len; i += 4) {
        d0 = data[i + 0];
        d1 = data[i + 1];
        d2 = data[i + 2];
        d3 = data[i + 3];

        if (d0 || d1 || d2 || d3) {
            return false;
        }
    }

    return true;
}

#ifndef _WIN32
/* Sets a specific flag */
int fcntl_setfl(int fd, int flag)
{
    int flags;

    flags = fcntl(fd, F_GETFL);
    if (flags == -1)
        return -errno;

    if (fcntl(fd, F_SETFL, flags | flag) == -1)
        return -errno;

    return 0;
}
#endif

static int64_t suffix_mul(char suffix, int64_t unit)
{
    switch (qemu_toupper(suffix)) {
    case STRTOSZ_DEFSUFFIX_B:
        return 1;
    case STRTOSZ_DEFSUFFIX_KB:
        return unit;
    case STRTOSZ_DEFSUFFIX_MB:
        return unit * unit;
    case STRTOSZ_DEFSUFFIX_GB:
        return unit * unit * unit;
    case STRTOSZ_DEFSUFFIX_TB:
        return unit * unit * unit * unit;
    case STRTOSZ_DEFSUFFIX_PB:
        return unit * unit * unit * unit * unit;
    case STRTOSZ_DEFSUFFIX_EB:
        return unit * unit * unit * unit * unit * unit;
    }
    return -1;
}

/*
 * Convert string to bytes, allowing either B/b for bytes, K/k for KB,
 * M/m for MB, G/g for GB or T/t for TB. End pointer will be returned
 * in *end, if not NULL. Return -ERANGE on overflow, Return -EINVAL on
 * other error.
 */
int64_t strtosz_suffix_unit(const char *nptr, char **end,
                            const char default_suffix, int64_t unit)
{
    int64_t retval = -EINVAL;
    char *endptr;
    unsigned char c;
    int mul_required = 0;
    double val, mul, integral, fraction;

    errno = 0;
    val = strtod(nptr, &endptr);
    if (isnan(val) || endptr == nptr || errno != 0) {
        goto fail;
    }
    fraction = modf(val, &integral);
    if (fraction != 0) {
        mul_required = 1;
    }
    c = *endptr;
    mul = suffix_mul(c, unit);
    if (mul >= 0) {
        endptr++;
    } else {
        mul = suffix_mul(default_suffix, unit);
        assert(mul >= 0);
    }
    if (mul == 1 && mul_required) {
        goto fail;
    }
    if ((val * mul >= INT64_MAX) || val < 0) {
        retval = -ERANGE;
        goto fail;
    }
    retval = val * mul;

fail:
    if (end) {
        *end = endptr;
    }

    return retval;
}

int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix)
{
    return strtosz_suffix_unit(nptr, end, default_suffix, 1024);
}

int64_t strtosz(const char *nptr, char **end)
{
    return strtosz_suffix(nptr, end, STRTOSZ_DEFSUFFIX_MB);
}

/**
 * parse_uint:
 *
 * @s: String to parse
 * @value: Destination for parsed integer value
 * @endptr: Destination for pointer to first character not consumed
 * @base: integer base, between 2 and 36 inclusive, or 0
 *
 * Parse unsigned integer
 *
 * Parsed syntax is like strtoull()'s: arbitrary whitespace, a single optional
 * '+' or '-', an optional "0x" if @base is 0 or 16, one or more digits.
 *
 * If @s is null, or @base is invalid, or @s doesn't start with an
 * integer in the syntax above, set *@value to 0, *@endptr to @s, and
 * return -EINVAL.
 *
 * Set *@endptr to point right beyond the parsed integer (even if the integer
 * overflows or is negative, all digits will be parsed and *@endptr will
 * point right beyond them).
 *
 * If the integer is negative, set *@value to 0, and return -ERANGE.
 *
 * If the integer overflows unsigned long long, set *@value to
 * ULLONG_MAX, and return -ERANGE.
 *
 * Else, set *@value to the parsed integer, and return 0.
 */
int parse_uint(const char *s, unsigned long long *value, char **endptr,
               int base)
{
    int r = 0;
    char *endp = (char *)s;
    unsigned long long val = 0;

    if (!s) {
        r = -EINVAL;
        goto out;
    }

    errno = 0;
    val = strtoull(s, &endp, base);
    if (errno) {
        r = -errno;
        goto out;
    }

    if (endp == s) {
        r = -EINVAL;
        goto out;
    }

    /* make sure we reject negative numbers: */
    while (isspace((unsigned char)*s)) {
        s++;
    }
    if (*s == '-') {
        val = 0;
        r = -ERANGE;
        goto out;
    }

out:
    *value = val;
    *endptr = endp;
    return r;
}

/**
 * parse_uint_full:
 *
 * @s: String to parse
 * @value: Destination for parsed integer value
 * @base: integer base, between 2 and 36 inclusive, or 0
 *
 * Parse unsigned integer from entire string
 *
 * Have the same behavior of parse_uint(), but with an additional check
 * for additional data after the parsed number. If extra characters are present
 * after the parsed number, the function will return -EINVAL, and *@v will
 * be set to 0.
 */
int parse_uint_full(const char *s, unsigned long long *value, int base)
{
    char *endp;
    int r;

    r = parse_uint(s, value, &endp, base);
    if (r < 0) {
        return r;
    }
    if (*endp) {
        *value = 0;
        return -EINVAL;
    }

    return 0;
}

int qemu_parse_fd(const char *param)
{
    int fd;
    char *endptr = NULL;

    fd = strtol(param, &endptr, 10);
    if (*endptr || (fd == 0 && param == endptr)) {
        return -1;
    }
    return fd;
}

/* round down to the nearest power of 2*/
int64_t pow2floor(int64_t value)
{
    if (!is_power_of_2(value)) {
        value = 0x8000000000000000ULL >> clz64(value);
    }
    return value;
}

/*
 * Implementation of  ULEB128 (http://en.wikipedia.org/wiki/LEB128)
 * Input is limited to 14-bit numbers
 */
int uleb128_encode_small(uint8_t *out, uint32_t n)
{
    g_assert(n <= 0x3fff);
    if (n < 0x80) {
        *out++ = n;
        return 1;
    } else {
        *out++ = (n & 0x7f) | 0x80;
        *out++ = n >> 7;
        return 2;
    }
}

int uleb128_decode_small(const uint8_t *in, uint32_t *n)
{
    if (!(*in & 0x80)) {
        *n = *in++;
        return 1;
    } else {
        *n = *in++ & 0x7f;
        /* we exceed 14 bit number */
        if (*in & 0x80) {
            return -1;
        }
        *n |= *in++ << 7;
        return 2;
    }
}

/*
 * helper to parse debug environment variables
 */
int parse_debug_env(const char *name, int max, int initial)
{
    char *debug_env = getenv(name);
    char *inv = NULL;
    int debug;

    if (!debug_env) {
        return initial;
    }
    debug = strtol(debug_env, &inv, 10);
    if (inv == debug_env) {
        return initial;
    }
    if (debug < 0 || debug > max) {
        fprintf(stderr, "warning: %s not in [0, %d]", name, max);
        return initial;
    }
    return debug;
}