diff options
Diffstat (limited to 'contrib/qemu/util/cutils.c')
| -rw-r--r-- | contrib/qemu/util/cutils.c | 532 | 
1 files changed, 532 insertions, 0 deletions
diff --git a/contrib/qemu/util/cutils.c b/contrib/qemu/util/cutils.c new file mode 100644 index 00000000000..0116fcde74f --- /dev/null +++ b/contrib/qemu/util/cutils.c @@ -0,0 +1,532 @@ +/* + * 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 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; +}  | 
