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-rw-r--r--util/cutils.c325
1 files changed, 325 insertions, 0 deletions
diff --git a/util/cutils.c b/util/cutils.c
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+/*
+ * 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;
+    }
+}