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Diffstat (limited to 'util/cutils.c')
-rw-r--r-- | util/cutils.c | 325 |
1 files changed, 325 insertions, 0 deletions
diff --git a/util/cutils.c b/util/cutils.c new file mode 100644 index 0000000000..80bb1dcbf7 --- /dev/null +++ b/util/cutils.c @@ -0,0 +1,325 @@ +/* + * 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; +} + +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 CONFIG_FDATASYNC + return fdatasync(fd); +#else + return fsync(fd); +#endif +} + +/* + * 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; + + 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; + } + 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); +} + +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; + } +} |