Archipelago » qemu

/*

 * 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 "host-utils.h"

#include <math.h>

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 = 86400 * (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

}

/* io vectors */

void qemu_iovec_init(QEMUIOVector *qiov, int alloc_hint)

{

    qiov->iov = qemu_malloc(alloc_hint * sizeof(struct iovec));

    qiov->niov = 0;

    qiov->nalloc = alloc_hint;

    qiov->size = 0;

}

void qemu_iovec_init_external(QEMUIOVector *qiov, struct iovec *iov, int niov)

{

    int i;

    qiov->iov = iov;

    qiov->niov = niov;

    qiov->nalloc = -1;

    qiov->size = 0;

    for (i = 0; i < niov; i++)

        qiov->size += iov[i].iov_len;

}

void qemu_iovec_add(QEMUIOVector *qiov, void *base, size_t len)

{

    assert(qiov->nalloc != -1);

    if (qiov->niov == qiov->nalloc) {

        qiov->nalloc = 2 * qiov->nalloc + 1;

        qiov->iov = qemu_realloc(qiov->iov, qiov->nalloc * sizeof(struct iovec));

    }

    qiov->iov[qiov->niov].iov_base = base;

    qiov->iov[qiov->niov].iov_len = len;

    qiov->size += len;

    ++qiov->niov;

}

/*

 * Copies iovecs from src to the end of dst. It starts copying after skipping

 * the given number of bytes in src and copies until src is completely copied

 * or the total size of the copied iovec reaches size.The size of the last

 * copied iovec is changed in order to fit the specified total size if it isn't

 * a perfect fit already.

 */

void qemu_iovec_copy(QEMUIOVector *dst, QEMUIOVector *src, uint64_t skip,

    size_t size)

{

    int i;

    size_t done;

    void *iov_base;

    uint64_t iov_len;

    assert(dst->nalloc != -1);

    done = 0;

    for (i = 0; (i < src->niov) && (done != size); i++) {

        if (skip >= src->iov[i].iov_len) {

            /* Skip the whole iov */

            skip -= src->iov[i].iov_len;

            continue;

        } else {

            /* Skip only part (or nothing) of the iov */

            iov_base = (uint8_t*) src->iov[i].iov_base + skip;

            iov_len = src->iov[i].iov_len - skip;

            skip = 0;

        }

        if (done + iov_len > size) {

            qemu_iovec_add(dst, iov_base, size - done);

            break;

        } else {

            qemu_iovec_add(dst, iov_base, iov_len);

        }

        done += iov_len;

    }

}

void qemu_iovec_concat(QEMUIOVector *dst, QEMUIOVector *src, size_t size)

{

    qemu_iovec_copy(dst, src, 0, size);

}

void qemu_iovec_destroy(QEMUIOVector *qiov)

{

    assert(qiov->nalloc != -1);

    qemu_free(qiov->iov);

}

void qemu_iovec_reset(QEMUIOVector *qiov)

{

    assert(qiov->nalloc != -1);

    qiov->niov = 0;

    qiov->size = 0;

}

void qemu_iovec_to_buffer(QEMUIOVector *qiov, void *buf)

{

    uint8_t *p = (uint8_t *)buf;

    int i;

    for (i = 0; i < qiov->niov; ++i) {

        memcpy(p, qiov->iov[i].iov_base, qiov->iov[i].iov_len);

        p += qiov->iov[i].iov_len;

    }

}

void qemu_iovec_from_buffer(QEMUIOVector *qiov, const void *buf, size_t count)

{

    const uint8_t *p = (const uint8_t *)buf;

    size_t copy;

    int i;

    for (i = 0; i < qiov->niov && count; ++i) {

        copy = count;

        if (copy > qiov->iov[i].iov_len)

            copy = qiov->iov[i].iov_len;

        memcpy(qiov->iov[i].iov_base, p, copy);

        p     += copy;

        count -= copy;

    }

}

void qemu_iovec_memset(QEMUIOVector *qiov, int c, size_t count)

{

    size_t n;

    int i;

    for (i = 0; i < qiov->niov && count; ++i) {

        n = MIN(count, qiov->iov[i].iov_len);

        memset(qiov->iov[i].iov_base, c, n);

        count -= n;

    }

}

#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

/*

 * 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. Default without any postfix

 * is MB. End pointer will be returned in *end, if not NULL. A valid

 * value must be terminated by whitespace, ',' or '\0'. Return -1 on

 * error.

 */

ssize_t strtosz(const char *nptr, char **end)

{

    ssize_t retval = -1;

    char *endptr, 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;

    }

    integral = modf(val, &fraction);

    if (integral != 0) {

        mul_required = 1;

    }

    /*

     * Any whitespace character is fine for terminating the number,

     * in addition we accept ',' to handle strings where the size is

     * part of a multi token argument.

     */

    c = *endptr;

    if (isspace(c) || c == '\0' || c == ',') {

        c = 0;

    }

    switch (c) {

    case 'B':

    case 'b':

        mul = 1;

        if (mul_required) {

            goto fail;

        }

        break;

    case 'K':

    case 'k':

        mul = 1 << 10;

        break;

    case 0:

        if (mul_required) {

            goto fail;

        }

    case 'M':

    case 'm':

        mul = 1ULL << 20;

        break;

    case 'G':

    case 'g':

        mul = 1ULL << 30;

        break;

    case 'T':

    case 't':

        mul = 1ULL << 40;

        break;

    default:

        goto fail;

    }

    /*

     * If not terminated by whitespace, ',', or \0, increment endptr

     * to point to next character, then check that we are terminated

     * by an appropriate separating character, ie. whitespace, ',', or

     * \0. If not, we are seeing trailing garbage, thus fail.

     */

    if (c != 0) {

        endptr++;

        if (!isspace(*endptr) && *endptr != ',' && *endptr != 0) {

            goto fail;

        }

    }

    if ((val * mul >= ~(size_t)0) || val < 0) {

        goto fail;

    }

    retval = val * mul;

fail:

    if (end) {

        *end = endptr;

    }

    return retval;

}