/* * 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 CONFIG_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; }