2 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
31 #include "byte-order.h"
34 #include "ovs-thread.h"
35 #include "socket-util.h"
37 #ifdef HAVE_PTHREAD_SET_NAME_NP
38 #include <pthread_np.h>
41 VLOG_DEFINE_THIS_MODULE(util);
43 COVERAGE_DEFINE(util_xalloc);
45 /* argv[0] without directory names. */
48 /* Name for the currently running thread or process, for log messages, process
49 * listings, and debuggers. */
50 DEFINE_PER_THREAD_MALLOCED_DATA(char *, subprogram_name);
52 /* --version option output. */
53 static char *program_version;
55 /* Buffer used by ovs_strerror() and ovs_format_message(). */
56 DEFINE_STATIC_PER_THREAD_DATA(struct { char s[128]; },
60 static char *xreadlink(const char *filename);
63 ovs_assert_failure(const char *where, const char *function,
64 const char *condition)
66 /* Prevent an infinite loop (or stack overflow) in case VLOG_ABORT happens
67 * to trigger an assertion failure of its own. */
68 static int reentry = 0;
72 VLOG_ABORT("%s: assertion %s failed in %s()",
73 where, condition, function);
77 fprintf(stderr, "%s: assertion %s failed in %s()",
78 where, condition, function);
89 ovs_abort(0, "virtual memory exhausted");
93 xcalloc(size_t count, size_t size)
95 void *p = count && size ? calloc(count, size) : malloc(1);
96 COVERAGE_INC(util_xalloc);
106 return xcalloc(1, size);
112 void *p = malloc(size ? size : 1);
113 COVERAGE_INC(util_xalloc);
121 xrealloc(void *p, size_t size)
123 p = realloc(p, size ? size : 1);
124 COVERAGE_INC(util_xalloc);
132 xmemdup(const void *p_, size_t size)
134 void *p = xmalloc(size);
140 xmemdup0(const char *p_, size_t length)
142 char *p = xmalloc(length + 1);
143 memcpy(p, p_, length);
149 xstrdup(const char *s)
151 return xmemdup0(s, strlen(s));
155 xvasprintf(const char *format, va_list args)
161 va_copy(args2, args);
162 needed = vsnprintf(NULL, 0, format, args);
164 s = xmalloc(needed + 1);
166 vsnprintf(s, needed + 1, format, args2);
173 x2nrealloc(void *p, size_t *n, size_t s)
175 *n = *n == 0 ? 1 : 2 * *n;
176 return xrealloc(p, *n * s);
179 /* The desired minimum alignment for an allocated block of memory. */
180 #define MEM_ALIGN MAX(sizeof(void *), 8)
181 BUILD_ASSERT_DECL(IS_POW2(MEM_ALIGN));
182 BUILD_ASSERT_DECL(CACHE_LINE_SIZE >= MEM_ALIGN);
184 /* Allocates and returns 'size' bytes of memory in dedicated cache lines. That
185 * is, the memory block returned will not share a cache line with other data,
186 * avoiding "false sharing". (The memory returned will not be at the start of
187 * a cache line, though, so don't assume such alignment.)
189 * Use free_cacheline() to free the returned memory block. */
191 xmalloc_cacheline(size_t size)
193 #ifdef HAVE_POSIX_MEMALIGN
197 COVERAGE_INC(util_xalloc);
198 error = posix_memalign(&p, CACHE_LINE_SIZE, size ? size : 1);
207 /* Allocate room for:
209 * - Up to CACHE_LINE_SIZE - 1 bytes before the payload, so that the
210 * start of the payload doesn't potentially share a cache line.
212 * - A payload consisting of a void *, followed by padding out to
213 * MEM_ALIGN bytes, followed by 'size' bytes of user data.
215 * - Space following the payload up to the end of the cache line, so
216 * that the end of the payload doesn't potentially share a cache line
217 * with some following block. */
218 base = xmalloc((CACHE_LINE_SIZE - 1)
219 + ROUND_UP(MEM_ALIGN + size, CACHE_LINE_SIZE));
221 /* Locate the payload and store a pointer to the base at the beginning. */
222 payload = (void **) ROUND_UP((uintptr_t) base, CACHE_LINE_SIZE);
225 return (char *) payload + MEM_ALIGN;
229 /* Like xmalloc_cacheline() but clears the allocated memory to all zero
232 xzalloc_cacheline(size_t size)
234 void *p = xmalloc_cacheline(size);
239 /* Frees a memory block allocated with xmalloc_cacheline() or
240 * xzalloc_cacheline(). */
242 free_cacheline(void *p)
244 #ifdef HAVE_POSIX_MEMALIGN
248 free(*(void **) ((uintptr_t) p - MEM_ALIGN));
254 xasprintf(const char *format, ...)
259 va_start(args, format);
260 s = xvasprintf(format, args);
266 /* Similar to strlcpy() from OpenBSD, but it never reads more than 'size - 1'
267 * bytes from 'src' and doesn't return anything. */
269 ovs_strlcpy(char *dst, const char *src, size_t size)
272 size_t len = strnlen(src, size - 1);
273 memcpy(dst, src, len);
278 /* Copies 'src' to 'dst'. Reads no more than 'size - 1' bytes from 'src'.
279 * Always null-terminates 'dst' (if 'size' is nonzero), and writes a zero byte
280 * to every otherwise unused byte in 'dst'.
282 * Except for performance, the following call:
283 * ovs_strzcpy(dst, src, size);
284 * is equivalent to these two calls:
285 * memset(dst, '\0', size);
286 * ovs_strlcpy(dst, src, size);
288 * (Thus, ovs_strzcpy() is similar to strncpy() without some of the pitfalls.)
291 ovs_strzcpy(char *dst, const char *src, size_t size)
294 size_t len = strnlen(src, size - 1);
295 memcpy(dst, src, len);
296 memset(dst + len, '\0', size - len);
300 /* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
301 * nonzero, then it is formatted with ovs_retval_to_string() and appended to
302 * the message inside parentheses. Then, terminates with abort().
304 * This function is preferred to ovs_fatal() in a situation where it would make
305 * sense for a monitoring process to restart the daemon.
307 * 'format' should not end with a new-line, because this function will add one
310 ovs_abort(int err_no, const char *format, ...)
314 va_start(args, format);
315 ovs_abort_valist(err_no, format, args);
318 /* Same as ovs_abort() except that the arguments are supplied as a va_list. */
320 ovs_abort_valist(int err_no, const char *format, va_list args)
322 ovs_error_valist(err_no, format, args);
326 /* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
327 * nonzero, then it is formatted with ovs_retval_to_string() and appended to
328 * the message inside parentheses. Then, terminates with EXIT_FAILURE.
330 * 'format' should not end with a new-line, because this function will add one
333 ovs_fatal(int err_no, const char *format, ...)
337 va_start(args, format);
338 ovs_fatal_valist(err_no, format, args);
341 /* Same as ovs_fatal() except that the arguments are supplied as a va_list. */
343 ovs_fatal_valist(int err_no, const char *format, va_list args)
345 ovs_error_valist(err_no, format, args);
349 /* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
350 * nonzero, then it is formatted with ovs_retval_to_string() and appended to
351 * the message inside parentheses.
353 * 'format' should not end with a new-line, because this function will add one
356 ovs_error(int err_no, const char *format, ...)
360 va_start(args, format);
361 ovs_error_valist(err_no, format, args);
365 /* Same as ovs_error() except that the arguments are supplied as a va_list. */
367 ovs_error_valist(int err_no, const char *format, va_list args)
369 const char *subprogram_name = get_subprogram_name();
370 int save_errno = errno;
372 if (subprogram_name[0]) {
373 fprintf(stderr, "%s(%s): ", program_name, subprogram_name);
375 fprintf(stderr, "%s: ", program_name);
378 vfprintf(stderr, format, args);
380 fprintf(stderr, " (%s)", ovs_retval_to_string(err_no));
387 /* Many OVS functions return an int which is one of:
390 * - EOF: end of file (not necessarily an error; depends on the function called)
392 * Returns the appropriate human-readable string. The caller must copy the
393 * string if it wants to hold onto it, as the storage may be overwritten on
394 * subsequent function calls.
397 ovs_retval_to_string(int retval)
400 : retval == EOF ? "End of file"
401 : ovs_strerror(retval));
404 /* This function returns the string describing the error number in 'error'
405 * for POSIX platforms. For Windows, this function can be used for C library
406 * calls. For socket calls that are also used in Windows, use sock_strerror()
407 * instead. For WINAPI calls, look at ovs_lasterror_to_string(). */
409 ovs_strerror(int error)
411 enum { BUFSIZE = sizeof strerror_buffer_get()->s };
417 buffer = strerror_buffer_get()->s;
419 #if STRERROR_R_CHAR_P
420 /* GNU style strerror_r() might return an immutable static string, or it
421 * might write and return 'buffer', but in either case we can pass the
422 * returned string directly to the caller. */
423 s = strerror_r(error, buffer, BUFSIZE);
424 #else /* strerror_r() returns an int. */
426 if (strerror_r(error, buffer, BUFSIZE)) {
427 /* strerror_r() is only allowed to fail on ERANGE (because the buffer
428 * is too short). We don't check the actual failure reason because
429 * POSIX requires strerror_r() to return the error but old glibc
430 * (before 2.13) returns -1 and sets errno. */
431 snprintf(buffer, BUFSIZE, "Unknown error %d", error);
440 /* Sets global "program_name" and "program_version" variables. Should
441 * be called at the beginning of main() with "argv[0]" as the argument
444 * 'version' should contain the version of the caller's program. If 'version'
445 * is the same as the VERSION #define, the caller is assumed to be part of Open
446 * vSwitch. Otherwise, it is assumed to be an external program linking against
447 * the Open vSwitch libraries.
449 * The 'date' and 'time' arguments should likely be called with
450 * "__DATE__" and "__TIME__" to use the time the binary was built.
451 * Alternatively, the "set_program_name" macro may be called to do this
455 set_program_name__(const char *argv0, const char *version, const char *date,
460 size_t max_len = strlen(argv0) + 1;
462 SetErrorMode(GetErrorMode() | SEM_NOGPFAULTERRORBOX);
463 _set_output_format(_TWO_DIGIT_EXPONENT);
465 basename = xmalloc(max_len);
466 _splitpath_s(argv0, NULL, 0, NULL, 0, basename, max_len, NULL, 0);
468 const char *slash = strrchr(argv0, '/');
469 basename = xstrdup(slash ? slash + 1 : argv0);
472 assert_single_threaded();
474 /* Remove libtool prefix, if it is there */
475 if (strncmp(basename, "lt-", 3) == 0) {
476 char *tmp_name = basename;
477 basename = xstrdup(basename + 3);
480 program_name = basename;
482 free(program_version);
483 if (!strcmp(version, VERSION)) {
484 program_version = xasprintf("%s (Open vSwitch) "VERSION"\n"
486 program_name, date, time);
488 program_version = xasprintf("%s %s\n"
489 "Open vSwitch Library "VERSION"\n"
491 program_name, version, date, time);
495 /* Returns the name of the currently running thread or process. */
497 get_subprogram_name(void)
499 const char *name = subprogram_name_get();
500 return name ? name : "";
503 /* Sets the formatted value of 'format' as the name of the currently running
504 * thread or process. (This appears in log messages and may also be visible in
505 * system process listings and debuggers.) */
507 set_subprogram_name(const char *format, ...)
514 va_start(args, format);
515 pname = xvasprintf(format, args);
518 pname = xstrdup(program_name);
521 free(subprogram_name_set(pname));
523 #if HAVE_GLIBC_PTHREAD_SETNAME_NP
524 pthread_setname_np(pthread_self(), pname);
525 #elif HAVE_NETBSD_PTHREAD_SETNAME_NP
526 pthread_setname_np(pthread_self(), "%s", pname);
527 #elif HAVE_PTHREAD_SET_NAME_NP
528 pthread_set_name_np(pthread_self(), pname);
532 /* Returns a pointer to a string describing the program version. The
533 * caller must not modify or free the returned string.
536 get_program_version(void)
538 return program_version;
541 /* Print the version information for the program. */
543 ovs_print_version(uint8_t min_ofp, uint8_t max_ofp)
545 printf("%s", program_version);
546 if (min_ofp || max_ofp) {
547 printf("OpenFlow versions %#x:%#x\n", min_ofp, max_ofp);
551 /* Writes the 'size' bytes in 'buf' to 'stream' as hex bytes arranged 16 per
552 * line. Numeric offsets are also included, starting at 'ofs' for the first
553 * byte in 'buf'. If 'ascii' is true then the corresponding ASCII characters
554 * are also rendered alongside. */
556 ovs_hex_dump(FILE *stream, const void *buf_, size_t size,
557 uintptr_t ofs, bool ascii)
559 const uint8_t *buf = buf_;
560 const size_t per_line = 16; /* Maximum bytes per line. */
564 size_t start, end, n;
567 /* Number of bytes on this line. */
568 start = ofs % per_line;
570 if (end - start > size)
575 fprintf(stream, "%08"PRIxMAX" ", (uintmax_t) ROUND_DOWN(ofs, per_line));
576 for (i = 0; i < start; i++)
577 fprintf(stream, " ");
579 fprintf(stream, "%02x%c",
580 buf[i - start], i == per_line / 2 - 1? '-' : ' ');
583 for (; i < per_line; i++)
584 fprintf(stream, " ");
585 fprintf(stream, "|");
586 for (i = 0; i < start; i++)
587 fprintf(stream, " ");
588 for (; i < end; i++) {
589 int c = buf[i - start];
590 putc(c >= 32 && c < 127 ? c : '.', stream);
592 for (; i < per_line; i++)
593 fprintf(stream, " ");
594 fprintf(stream, "|");
596 fprintf(stream, "\n");
605 str_to_int(const char *s, int base, int *i)
608 bool ok = str_to_llong(s, base, &ll);
614 str_to_long(const char *s, int base, long *li)
617 bool ok = str_to_llong(s, base, &ll);
623 str_to_llong(const char *s, int base, long long *x)
625 int save_errno = errno;
628 *x = strtoll(s, &tail, base);
629 if (errno == EINVAL || errno == ERANGE || tail == s || *tail != '\0') {
640 str_to_uint(const char *s, int base, unsigned int *u)
643 bool ok = str_to_llong(s, base, &ll);
644 if (!ok || ll < 0 || ll > UINT_MAX) {
653 /* Converts floating-point string 's' into a double. If successful, stores
654 * the double in '*d' and returns true; on failure, stores 0 in '*d' and
657 * Underflow (e.g. "1e-9999") is not considered an error, but overflow
658 * (e.g. "1e9999)" is. */
660 str_to_double(const char *s, double *d)
662 int save_errno = errno;
665 *d = strtod(s, &tail);
666 if (errno == EINVAL || (errno == ERANGE && *d != 0)
667 || tail == s || *tail != '\0') {
677 /* Returns the value of 'c' as a hexadecimal digit. */
682 case '0': case '1': case '2': case '3': case '4':
683 case '5': case '6': case '7': case '8': case '9':
709 /* Returns the integer value of the 'n' hexadecimal digits starting at 's', or
710 * UINTMAX_MAX if one of those "digits" is not really a hex digit. Sets '*ok'
711 * to true if the conversion succeeds or to false if a non-hex digit is
714 hexits_value(const char *s, size_t n, bool *ok)
720 for (i = 0; i < n; i++) {
721 int hexit = hexit_value(s[i]);
726 value = (value << 4) + hexit;
732 /* Returns the current working directory as a malloc()'d string, or a null
733 * pointer if the current working directory cannot be determined. */
740 /* Get maximum path length or at least a reasonable estimate. */
742 path_max = pathconf(".", _PC_PATH_MAX);
746 size = (path_max < 0 ? 1024
747 : path_max > 10240 ? 10240
750 /* Get current working directory. */
752 char *buf = xmalloc(size);
753 if (getcwd(buf, size)) {
754 return xrealloc(buf, strlen(buf) + 1);
758 if (error != ERANGE) {
759 VLOG_WARN("getcwd failed (%s)", ovs_strerror(error));
768 all_slashes_name(const char *s)
770 return xstrdup(s[0] == '/' && s[1] == '/' && s[2] != '/' ? "//"
776 /* Returns the directory name portion of 'file_name' as a malloc()'d string,
777 * similar to the POSIX dirname() function but thread-safe. */
779 dir_name(const char *file_name)
781 size_t len = strlen(file_name);
782 while (len > 0 && file_name[len - 1] == '/') {
785 while (len > 0 && file_name[len - 1] != '/') {
788 while (len > 0 && file_name[len - 1] == '/') {
791 return len ? xmemdup0(file_name, len) : all_slashes_name(file_name);
794 /* Returns the file name portion of 'file_name' as a malloc()'d string,
795 * similar to the POSIX basename() function but thread-safe. */
797 base_name(const char *file_name)
801 end = strlen(file_name);
802 while (end > 0 && file_name[end - 1] == '/') {
807 return all_slashes_name(file_name);
811 while (start > 0 && file_name[start - 1] != '/') {
815 return xmemdup0(file_name + start, end - start);
819 /* If 'file_name' starts with '/', returns a copy of 'file_name'. Otherwise,
820 * returns an absolute path to 'file_name' considering it relative to 'dir',
821 * which itself must be absolute. 'dir' may be null or the empty string, in
822 * which case the current working directory is used.
824 * Returns a null pointer if 'dir' is null and getcwd() fails. */
826 abs_file_name(const char *dir, const char *file_name)
828 if (file_name[0] == '/') {
829 return xstrdup(file_name);
830 } else if (dir && dir[0]) {
831 char *separator = dir[strlen(dir) - 1] == '/' ? "" : "/";
832 return xasprintf("%s%s%s", dir, separator, file_name);
834 char *cwd = get_cwd();
836 char *abs_name = xasprintf("%s/%s", cwd, file_name);
845 /* Like readlink(), but returns the link name as a null-terminated string in
846 * allocated memory that the caller must eventually free (with free()).
847 * Returns NULL on error, in which case errno is set appropriately. */
849 xreadlink(const char *filename)
853 for (size = 64; ; size *= 2) {
854 char *buf = xmalloc(size);
855 ssize_t retval = readlink(filename, buf, size);
858 if (retval >= 0 && retval < size) {
871 /* Returns a version of 'filename' with symlinks in the final component
872 * dereferenced. This differs from realpath() in that:
874 * - 'filename' need not exist.
876 * - If 'filename' does exist as a symlink, its referent need not exist.
878 * - Only symlinks in the final component of 'filename' are dereferenced.
880 * For Windows platform, this function returns a string that has the same
881 * value as the passed string.
883 * The caller must eventually free the returned string (with free()). */
885 follow_symlinks(const char *filename)
892 fn = xstrdup(filename);
893 for (i = 0; i < 10; i++) {
897 if (lstat(fn, &s) != 0 || !S_ISLNK(s.st_mode)) {
901 linkname = xreadlink(fn);
903 VLOG_WARN("%s: readlink failed (%s)",
904 filename, ovs_strerror(errno));
908 if (linkname[0] == '/') {
909 /* Target of symlink is absolute so use it raw. */
912 /* Target of symlink is relative so add to 'fn''s directory. */
913 char *dir = dir_name(fn);
915 if (!strcmp(dir, ".")) {
918 char *separator = dir[strlen(dir) - 1] == '/' ? "" : "/";
919 next_fn = xasprintf("%s%s%s", dir, separator, linkname);
930 VLOG_WARN("%s: too many levels of symlinks", filename);
933 return xstrdup(filename);
936 /* Pass a value to this function if it is marked with
937 * __attribute__((warn_unused_result)) and you genuinely want to ignore
938 * its return value. (Note that every scalar type can be implicitly
939 * converted to bool.) */
940 void ignore(bool x OVS_UNUSED) { }
942 /* Returns an appropriate delimiter for inserting just before the 0-based item
943 * 'index' in a list that has 'total' items in it. */
945 english_list_delimiter(size_t index, size_t total)
947 return (index == 0 ? ""
948 : index < total - 1 ? ", "
949 : total > 2 ? ", and "
953 /* Returns the number of trailing 0-bits in 'n'. Undefined if 'n' == 0. */
954 #if __GNUC__ >= 4 || _MSC_VER
955 /* Defined inline in util.h. */
957 /* Returns the number of trailing 0-bits in 'n'. Undefined if 'n' == 0. */
964 #define CTZ_STEP(X) \
981 /* Returns the number of leading 0-bits in 'n'. Undefined if 'n' == 0. */
983 raw_clz64(uint64_t n)
988 #define CLZ_STEP(X) \
1006 #if NEED_COUNT_1BITS_8
1008 ((((X) & (1 << 0)) != 0) + \
1009 (((X) & (1 << 1)) != 0) + \
1010 (((X) & (1 << 2)) != 0) + \
1011 (((X) & (1 << 3)) != 0) + \
1012 (((X) & (1 << 4)) != 0) + \
1013 (((X) & (1 << 5)) != 0) + \
1014 (((X) & (1 << 6)) != 0) + \
1015 (((X) & (1 << 7)) != 0))
1016 #define INIT2(X) INIT1(X), INIT1((X) + 1)
1017 #define INIT4(X) INIT2(X), INIT2((X) + 2)
1018 #define INIT8(X) INIT4(X), INIT4((X) + 4)
1019 #define INIT16(X) INIT8(X), INIT8((X) + 8)
1020 #define INIT32(X) INIT16(X), INIT16((X) + 16)
1021 #define INIT64(X) INIT32(X), INIT32((X) + 32)
1023 const uint8_t count_1bits_8[256] = {
1024 INIT64(0), INIT64(64), INIT64(128), INIT64(192)
1028 /* Returns true if the 'n' bytes starting at 'p' are zeros. */
1030 is_all_zeros(const void *p_, size_t n)
1032 const uint8_t *p = p_;
1035 for (i = 0; i < n; i++) {
1043 /* Returns true if the 'n' bytes starting at 'p' are 0xff. */
1045 is_all_ones(const void *p_, size_t n)
1047 const uint8_t *p = p_;
1050 for (i = 0; i < n; i++) {
1058 /* Copies 'n_bits' bits starting from bit 'src_ofs' in 'src' to the 'n_bits'
1059 * starting from bit 'dst_ofs' in 'dst'. 'src' is 'src_len' bytes long and
1060 * 'dst' is 'dst_len' bytes long.
1062 * If you consider all of 'src' to be a single unsigned integer in network byte
1063 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1064 * with value 1 in src[src_len - 1], bit 1 is the bit with value 2, bit 2 is
1065 * the bit with value 4, ..., bit 8 is the bit with value 1 in src[src_len -
1066 * 2], and so on. Similarly for 'dst'.
1068 * Required invariants:
1069 * src_ofs + n_bits <= src_len * 8
1070 * dst_ofs + n_bits <= dst_len * 8
1071 * 'src' and 'dst' must not overlap.
1074 bitwise_copy(const void *src_, unsigned int src_len, unsigned int src_ofs,
1075 void *dst_, unsigned int dst_len, unsigned int dst_ofs,
1076 unsigned int n_bits)
1078 const uint8_t *src = src_;
1079 uint8_t *dst = dst_;
1081 src += src_len - (src_ofs / 8 + 1);
1084 dst += dst_len - (dst_ofs / 8 + 1);
1087 if (src_ofs == 0 && dst_ofs == 0) {
1088 unsigned int n_bytes = n_bits / 8;
1092 memcpy(dst, src, n_bytes);
1099 uint8_t mask = (1 << n_bits) - 1;
1100 *dst = (*dst & ~mask) | (*src & mask);
1103 while (n_bits > 0) {
1104 unsigned int max_copy = 8 - MAX(src_ofs, dst_ofs);
1105 unsigned int chunk = MIN(n_bits, max_copy);
1106 uint8_t mask = ((1 << chunk) - 1) << dst_ofs;
1109 *dst |= ((*src >> src_ofs) << dst_ofs) & mask;
1126 /* Zeros the 'n_bits' bits starting from bit 'dst_ofs' in 'dst'. 'dst' is
1127 * 'dst_len' bytes long.
1129 * If you consider all of 'dst' to be a single unsigned integer in network byte
1130 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1131 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1132 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1135 * Required invariant:
1136 * dst_ofs + n_bits <= dst_len * 8
1139 bitwise_zero(void *dst_, unsigned int dst_len, unsigned dst_ofs,
1140 unsigned int n_bits)
1142 uint8_t *dst = dst_;
1148 dst += dst_len - (dst_ofs / 8 + 1);
1152 unsigned int chunk = MIN(n_bits, 8 - dst_ofs);
1154 *dst &= ~(((1 << chunk) - 1) << dst_ofs);
1164 while (n_bits >= 8) {
1170 *dst &= ~((1 << n_bits) - 1);
1174 /* Sets to 1 all of the 'n_bits' bits starting from bit 'dst_ofs' in 'dst'.
1175 * 'dst' is 'dst_len' bytes long.
1177 * If you consider all of 'dst' to be a single unsigned integer in network byte
1178 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1179 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1180 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1183 * Required invariant:
1184 * dst_ofs + n_bits <= dst_len * 8
1187 bitwise_one(void *dst_, unsigned int dst_len, unsigned dst_ofs,
1188 unsigned int n_bits)
1190 uint8_t *dst = dst_;
1196 dst += dst_len - (dst_ofs / 8 + 1);
1200 unsigned int chunk = MIN(n_bits, 8 - dst_ofs);
1202 *dst |= ((1 << chunk) - 1) << dst_ofs;
1212 while (n_bits >= 8) {
1218 *dst |= (1 << n_bits) - 1;
1222 /* Scans the 'n_bits' bits starting from bit 'dst_ofs' in 'dst' for 1-bits.
1223 * Returns false if any 1-bits are found, otherwise true. 'dst' is 'dst_len'
1226 * If you consider all of 'dst' to be a single unsigned integer in network byte
1227 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1228 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1229 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1232 * Required invariant:
1233 * dst_ofs + n_bits <= dst_len * 8
1236 bitwise_is_all_zeros(const void *p_, unsigned int len, unsigned int ofs,
1237 unsigned int n_bits)
1239 const uint8_t *p = p_;
1245 p += len - (ofs / 8 + 1);
1249 unsigned int chunk = MIN(n_bits, 8 - ofs);
1251 if (*p & (((1 << chunk) - 1) << ofs)) {
1263 while (n_bits >= 8) {
1271 if (n_bits && *p & ((1 << n_bits) - 1)) {
1278 /* Scans the bits in 'p' that have bit offsets 'start' through 'end'
1279 * (inclusive) for the first bit with value 'target'. If one is found, returns
1280 * its offset, otherwise 'end'. 'p' is 'len' bytes long.
1282 * If you consider all of 'p' to be a single unsigned integer in network byte
1283 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1284 * with value 1 in p[len - 1], bit 1 is the bit with value 2, bit 2 is the bit
1285 * with value 4, ..., bit 8 is the bit with value 1 in p[len - 2], and so on.
1287 * Required invariant:
1291 bitwise_scan(const void *p_, unsigned int len, bool target, unsigned int start,
1294 const uint8_t *p = p_;
1297 for (ofs = start; ofs < end; ofs++) {
1298 bool bit = (p[len - (ofs / 8 + 1)] & (1u << (ofs % 8))) != 0;
1299 if (bit == target) {
1307 /* Copies the 'n_bits' low-order bits of 'value' into the 'n_bits' bits
1308 * starting at bit 'dst_ofs' in 'dst', which is 'dst_len' bytes long.
1310 * If you consider all of 'dst' to be a single unsigned integer in network byte
1311 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1312 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1313 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1316 * Required invariants:
1317 * dst_ofs + n_bits <= dst_len * 8
1321 bitwise_put(uint64_t value,
1322 void *dst, unsigned int dst_len, unsigned int dst_ofs,
1323 unsigned int n_bits)
1325 ovs_be64 n_value = htonll(value);
1326 bitwise_copy(&n_value, sizeof n_value, 0,
1327 dst, dst_len, dst_ofs,
1331 /* Returns the value of the 'n_bits' bits starting at bit 'src_ofs' in 'src',
1332 * which is 'src_len' bytes long.
1334 * If you consider all of 'src' to be a single unsigned integer in network byte
1335 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1336 * with value 1 in src[src_len - 1], bit 1 is the bit with value 2, bit 2 is
1337 * the bit with value 4, ..., bit 8 is the bit with value 1 in src[src_len -
1340 * Required invariants:
1341 * src_ofs + n_bits <= src_len * 8
1345 bitwise_get(const void *src, unsigned int src_len,
1346 unsigned int src_ofs, unsigned int n_bits)
1348 ovs_be64 value = htonll(0);
1350 bitwise_copy(src, src_len, src_ofs,
1351 &value, sizeof value, 0,
1353 return ntohll(value);
1374 skip_spaces(const char *s)
1376 while (isspace((unsigned char) *s)) {
1383 scan_int(const char *s, const struct scan_spec *spec, int base, va_list *args)
1385 const char *start = s;
1390 negative = *s == '-';
1391 s += *s == '-' || *s == '+';
1393 if ((!base || base == 16) && *s == '0' && (s[1] == 'x' || s[1] == 'X')) {
1397 base = *s == '0' ? 8 : 10;
1400 if (s - start >= spec->width) {
1406 while (s - start < spec->width) {
1407 int digit = hexit_value(*s);
1409 if (digit < 0 || digit >= base) {
1412 value = value * base + digit;
1424 switch (spec->type) {
1428 *va_arg(*args, char *) = value;
1431 *va_arg(*args, short int *) = value;
1434 *va_arg(*args, int *) = value;
1437 *va_arg(*args, long int *) = value;
1440 *va_arg(*args, long long int *) = value;
1443 *va_arg(*args, intmax_t *) = value;
1445 case SCAN_PTRDIFF_T:
1446 *va_arg(*args, ptrdiff_t *) = value;
1449 *va_arg(*args, size_t *) = value;
1456 skip_digits(const char *s)
1458 while (*s >= '0' && *s <= '9') {
1465 scan_float(const char *s, const struct scan_spec *spec, va_list *args)
1467 const char *start = s;
1473 s += *s == '+' || *s == '-';
1476 s = skip_digits(s + 1);
1478 if (*s == 'e' || *s == 'E') {
1480 s += *s == '+' || *s == '-';
1484 if (s - start > spec->width) {
1485 s = start + spec->width;
1488 copy = xmemdup0(start, s - start);
1489 value = strtold(copy, &tail);
1496 switch (spec->type) {
1500 *va_arg(*args, float *) = value;
1503 *va_arg(*args, double *) = value;
1506 *va_arg(*args, long double *) = value;
1512 case SCAN_PTRDIFF_T:
1520 scan_output_string(const struct scan_spec *spec,
1521 const char *s, size_t n,
1524 if (spec->type != SCAN_DISCARD) {
1525 char *out = va_arg(*args, char *);
1532 scan_string(const char *s, const struct scan_spec *spec, va_list *args)
1536 for (n = 0; n < spec->width; n++) {
1537 if (!s[n] || isspace((unsigned char) s[n])) {
1545 scan_output_string(spec, s, n, args);
1550 parse_scanset(const char *p_, unsigned long *set, bool *complemented)
1552 const uint8_t *p = (const uint8_t *) p_;
1554 *complemented = *p == '^';
1558 bitmap_set1(set, ']');
1562 while (*p && *p != ']') {
1563 if (p[1] == '-' && p[2] != ']' && p[2] > *p) {
1564 bitmap_set_multiple(set, *p, p[2] - *p + 1, true);
1567 bitmap_set1(set, *p++);
1573 return (const char *) p;
1577 scan_set(const char *s, const struct scan_spec *spec, const char **pp,
1580 unsigned long set[BITMAP_N_LONGS(UCHAR_MAX + 1)];
1584 /* Parse the scan set. */
1585 memset(set, 0, sizeof set);
1586 *pp = parse_scanset(*pp, set, &complemented);
1588 /* Parse the data. */
1591 && bitmap_is_set(set, (unsigned char) s[n]) == !complemented
1592 && n < spec->width) {
1598 scan_output_string(spec, s, n, args);
1603 scan_chars(const char *s, const struct scan_spec *spec, va_list *args)
1605 unsigned int n = spec->width == UINT_MAX ? 1 : spec->width;
1607 if (strlen(s) < n) {
1610 if (spec->type != SCAN_DISCARD) {
1611 memcpy(va_arg(*args, char *), s, n);
1616 /* This is an implementation of the standard sscanf() function, with the
1617 * following exceptions:
1619 * - It returns true if the entire format was successfully scanned and
1620 * converted, false if any conversion failed.
1622 * - The standard doesn't define sscanf() behavior when an out-of-range value
1623 * is scanned, e.g. if a "%"PRIi8 conversion scans "-1" or "0x1ff". Some
1624 * implementations consider this an error and stop scanning. This
1625 * implementation never considers an out-of-range value an error; instead,
1626 * it stores the least-significant bits of the converted value in the
1627 * destination, e.g. the value 255 for both examples earlier.
1629 * - Only single-byte characters are supported, that is, the 'l' modifier
1630 * on %s, %[, and %c is not supported. The GNU extension 'a' modifier is
1631 * also not supported.
1633 * - %p is not supported.
1636 ovs_scan(const char *s, const char *format, ...)
1638 const char *const start = s;
1643 va_start(args, format);
1645 while (*p != '\0') {
1646 struct scan_spec spec;
1647 unsigned char c = *p++;
1653 } else if (c != '%') {
1659 } else if (*p == '%') {
1667 /* Parse '*' flag. */
1668 discard = *p == '*';
1671 /* Parse field width. */
1673 while (*p >= '0' && *p <= '9') {
1674 spec.width = spec.width * 10 + (*p++ - '0');
1676 if (spec.width == 0) {
1677 spec.width = UINT_MAX;
1680 /* Parse type modifier. */
1684 spec.type = SCAN_CHAR;
1687 spec.type = SCAN_SHORT;
1693 spec.type = SCAN_INTMAX_T;
1699 spec.type = SCAN_LLONG;
1702 spec.type = SCAN_LONG;
1709 spec.type = SCAN_LLONG;
1714 spec.type = SCAN_PTRDIFF_T;
1719 spec.type = SCAN_SIZE_T;
1724 spec.type = SCAN_INT;
1729 spec.type = SCAN_DISCARD;
1733 if (c != 'c' && c != 'n' && c != '[') {
1738 s = scan_int(s, &spec, 10, &args);
1742 s = scan_int(s, &spec, 0, &args);
1746 s = scan_int(s, &spec, 8, &args);
1750 s = scan_int(s, &spec, 10, &args);
1755 s = scan_int(s, &spec, 16, &args);
1763 s = scan_float(s, &spec, &args);
1767 s = scan_string(s, &spec, &args);
1771 s = scan_set(s, &spec, &p, &args);
1775 s = scan_chars(s, &spec, &args);
1779 if (spec.type != SCAN_DISCARD) {
1780 *va_arg(args, int *) = s - start;
1797 xsleep(unsigned int seconds)
1799 ovsrcu_quiesce_start();
1801 Sleep(seconds * 1000);
1805 ovsrcu_quiesce_end();
1811 ovs_format_message(int error)
1813 enum { BUFSIZE = sizeof strerror_buffer_get()->s };
1814 char *buffer = strerror_buffer_get()->s;
1816 FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
1817 NULL, error, 0, buffer, BUFSIZE, NULL);
1821 /* Returns a null-terminated string that explains the last error.
1822 * Use this function to get the error string for WINAPI calls. */
1824 ovs_lasterror_to_string(void)
1826 return ovs_format_message(GetLastError());
1830 ftruncate(int fd, off_t length)
1834 error = _chsize_s(fd, length);
1841 OVS_CONSTRUCTOR(winsock_start) {
1845 error = WSAStartup(MAKEWORD(2, 2), &wsaData);
1847 VLOG_FATAL("WSAStartup failed: %s", sock_strerror(sock_errno()));