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/*
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* Simple C functions to supplement the C library
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*
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* Copyright (c) 2006 Fabrice Bellard
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "qemu-common.h" |
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#include "host-utils.h" |
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#include <math.h> |
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#include "qemu_socket.h" |
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#include "iov.h" |
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void strpadcpy(char *buf, int buf_size, const char *str, char pad) |
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{ |
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int len = qemu_strnlen(str, buf_size);
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memcpy(buf, str, len); |
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memset(buf + len, pad, buf_size - len); |
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} |
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void pstrcpy(char *buf, int buf_size, const char *str) |
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{ |
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int c;
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char *q = buf;
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if (buf_size <= 0) |
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return;
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for(;;) {
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c = *str++; |
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if (c == 0 || q >= buf + buf_size - 1) |
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break;
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*q++ = c; |
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} |
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*q = '\0';
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} |
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/* strcat and truncate. */
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char *pstrcat(char *buf, int buf_size, const char *s) |
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{ |
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int len;
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len = strlen(buf); |
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if (len < buf_size)
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pstrcpy(buf + len, buf_size - len, s); |
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return buf;
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} |
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int strstart(const char *str, const char *val, const char **ptr) |
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{ |
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const char *p, *q; |
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p = str; |
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q = val; |
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while (*q != '\0') { |
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if (*p != *q)
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return 0; |
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p++; |
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q++; |
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} |
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if (ptr)
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*ptr = p; |
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return 1; |
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} |
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int stristart(const char *str, const char *val, const char **ptr) |
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{ |
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const char *p, *q; |
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p = str; |
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q = val; |
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while (*q != '\0') { |
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if (qemu_toupper(*p) != qemu_toupper(*q))
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return 0; |
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p++; |
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q++; |
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} |
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if (ptr)
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*ptr = p; |
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return 1; |
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} |
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/* XXX: use host strnlen if available ? */
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int qemu_strnlen(const char *s, int max_len) |
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{ |
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int i;
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for(i = 0; i < max_len; i++) { |
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if (s[i] == '\0') { |
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break;
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} |
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} |
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return i;
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} |
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time_t mktimegm(struct tm *tm)
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{ |
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time_t t; |
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int y = tm->tm_year + 1900, m = tm->tm_mon + 1, d = tm->tm_mday; |
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if (m < 3) { |
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m += 12;
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y--; |
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} |
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t = 86400ULL * (d + (153 * m - 457) / 5 + 365 * y + y / 4 - y / 100 + |
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y / 400 - 719469); |
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t += 3600 * tm->tm_hour + 60 * tm->tm_min + tm->tm_sec; |
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return t;
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} |
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int qemu_fls(int i) |
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{ |
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return 32 - clz32(i); |
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} |
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/*
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* Make sure data goes on disk, but if possible do not bother to
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* write out the inode just for timestamp updates.
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*
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* Unfortunately even in 2009 many operating systems do not support
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* fdatasync and have to fall back to fsync.
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*/
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int qemu_fdatasync(int fd) |
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{ |
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#ifdef CONFIG_FDATASYNC
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return fdatasync(fd);
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#else
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return fsync(fd);
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#endif
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} |
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/*
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* Checks if a buffer is all zeroes
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*
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* Attention! The len must be a multiple of 4 * sizeof(long) due to
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* restriction of optimizations in this function.
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*/
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bool buffer_is_zero(const void *buf, size_t len) |
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{ |
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/*
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* Use long as the biggest available internal data type that fits into the
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* CPU register and unroll the loop to smooth out the effect of memory
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* latency.
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*/
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size_t i; |
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long d0, d1, d2, d3;
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const long * const data = buf; |
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assert(len % (4 * sizeof(long)) == 0); |
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len /= sizeof(long); |
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for (i = 0; i < len; i += 4) { |
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d0 = data[i + 0];
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d1 = data[i + 1];
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d2 = data[i + 2];
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d3 = data[i + 3];
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if (d0 || d1 || d2 || d3) {
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return false; |
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} |
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} |
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return true; |
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} |
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#ifndef _WIN32
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/* Sets a specific flag */
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int fcntl_setfl(int fd, int flag) |
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{ |
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int flags;
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flags = fcntl(fd, F_GETFL); |
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if (flags == -1) |
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return -errno;
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if (fcntl(fd, F_SETFL, flags | flag) == -1) |
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return -errno;
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return 0; |
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} |
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#endif
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static int64_t suffix_mul(char suffix, int64_t unit) |
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{ |
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switch (qemu_toupper(suffix)) {
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case STRTOSZ_DEFSUFFIX_B:
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return 1; |
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case STRTOSZ_DEFSUFFIX_KB:
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return unit;
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case STRTOSZ_DEFSUFFIX_MB:
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return unit * unit;
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case STRTOSZ_DEFSUFFIX_GB:
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return unit * unit * unit;
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case STRTOSZ_DEFSUFFIX_TB:
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return unit * unit * unit * unit;
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} |
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return -1; |
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} |
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/*
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* Convert string to bytes, allowing either B/b for bytes, K/k for KB,
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* M/m for MB, G/g for GB or T/t for TB. End pointer will be returned
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* in *end, if not NULL. Return -1 on error.
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*/
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int64_t strtosz_suffix_unit(const char *nptr, char **end, |
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const char default_suffix, int64_t unit) |
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{ |
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int64_t retval = -1;
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char *endptr;
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unsigned char c; |
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int mul_required = 0; |
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double val, mul, integral, fraction;
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errno = 0;
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val = strtod(nptr, &endptr); |
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if (isnan(val) || endptr == nptr || errno != 0) { |
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goto fail;
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} |
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fraction = modf(val, &integral); |
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if (fraction != 0) { |
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mul_required = 1;
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} |
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c = *endptr; |
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mul = suffix_mul(c, unit); |
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if (mul >= 0) { |
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endptr++; |
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} else {
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mul = suffix_mul(default_suffix, unit); |
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assert(mul >= 0);
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} |
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if (mul == 1 && mul_required) { |
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goto fail;
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} |
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if ((val * mul >= INT64_MAX) || val < 0) { |
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goto fail;
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} |
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retval = val * mul; |
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fail:
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if (end) {
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*end = endptr; |
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} |
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return retval;
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} |
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int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix) |
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{ |
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return strtosz_suffix_unit(nptr, end, default_suffix, 1024); |
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} |
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int64_t strtosz(const char *nptr, char **end) |
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{ |
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return strtosz_suffix(nptr, end, STRTOSZ_DEFSUFFIX_MB);
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} |
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int qemu_parse_fd(const char *param) |
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{ |
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int fd;
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char *endptr = NULL; |
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fd = strtol(param, &endptr, 10);
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if (*endptr || (fd == 0 && param == endptr)) { |
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return -1; |
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} |
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return fd;
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} |
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int qemu_parse_fdset(const char *param) |
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{ |
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return qemu_parse_fd(param);
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} |
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/* round down to the nearest power of 2*/
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int64_t pow2floor(int64_t value) |
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{ |
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if (!is_power_of_2(value)) {
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value = 0x8000000000000000ULL >> clz64(value);
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} |
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return value;
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} |
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/*
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* Implementation of ULEB128 (http://en.wikipedia.org/wiki/LEB128)
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* Input is limited to 14-bit numbers
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*/
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int uleb128_encode_small(uint8_t *out, uint32_t n)
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{ |
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g_assert(n <= 0x3fff);
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if (n < 0x80) { |
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*out++ = n; |
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return 1; |
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} else {
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*out++ = (n & 0x7f) | 0x80; |
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*out++ = n >> 7;
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return 2; |
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} |
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} |
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int uleb128_decode_small(const uint8_t *in, uint32_t *n) |
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{ |
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if (!(*in & 0x80)) { |
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*n = *in++; |
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return 1; |
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} else {
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*n = *in++ & 0x7f;
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/* we exceed 14 bit number */
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if (*in & 0x80) { |
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return -1; |
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} |
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*n |= *in++ << 7;
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return 2; |
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} |
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} |