aboutsummaryrefslogtreecommitdiff
path: root/util/cutils.c
diff options
context:
space:
mode:
Diffstat (limited to 'util/cutils.c')
-rw-r--r--util/cutils.c325
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;
+ }
+}