2 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 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"
36 #include "openvswitch/vlog.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 nullable_xstrdup(const char *s)
157 return s ? xstrdup(s) : NULL;
161 xvasprintf(const char *format, va_list args)
167 va_copy(args2, args);
168 needed = vsnprintf(NULL, 0, format, args);
170 s = xmalloc(needed + 1);
172 vsnprintf(s, needed + 1, format, args2);
179 x2nrealloc(void *p, size_t *n, size_t s)
181 *n = *n == 0 ? 1 : 2 * *n;
182 return xrealloc(p, *n * s);
185 /* The desired minimum alignment for an allocated block of memory. */
186 #define MEM_ALIGN MAX(sizeof(void *), 8)
187 BUILD_ASSERT_DECL(IS_POW2(MEM_ALIGN));
188 BUILD_ASSERT_DECL(CACHE_LINE_SIZE >= MEM_ALIGN);
190 /* Allocates and returns 'size' bytes of memory in dedicated cache lines. That
191 * is, the memory block returned will not share a cache line with other data,
192 * avoiding "false sharing". (The memory returned will not be at the start of
193 * a cache line, though, so don't assume such alignment.)
195 * Use free_cacheline() to free the returned memory block. */
197 xmalloc_cacheline(size_t size)
199 #ifdef HAVE_POSIX_MEMALIGN
203 COVERAGE_INC(util_xalloc);
204 error = posix_memalign(&p, CACHE_LINE_SIZE, size ? size : 1);
213 /* Allocate room for:
215 * - Up to CACHE_LINE_SIZE - 1 bytes before the payload, so that the
216 * start of the payload doesn't potentially share a cache line.
218 * - A payload consisting of a void *, followed by padding out to
219 * MEM_ALIGN bytes, followed by 'size' bytes of user data.
221 * - Space following the payload up to the end of the cache line, so
222 * that the end of the payload doesn't potentially share a cache line
223 * with some following block. */
224 base = xmalloc((CACHE_LINE_SIZE - 1)
225 + ROUND_UP(MEM_ALIGN + size, CACHE_LINE_SIZE));
227 /* Locate the payload and store a pointer to the base at the beginning. */
228 payload = (void **) ROUND_UP((uintptr_t) base, CACHE_LINE_SIZE);
231 return (char *) payload + MEM_ALIGN;
235 /* Like xmalloc_cacheline() but clears the allocated memory to all zero
238 xzalloc_cacheline(size_t size)
240 void *p = xmalloc_cacheline(size);
245 /* Frees a memory block allocated with xmalloc_cacheline() or
246 * xzalloc_cacheline(). */
248 free_cacheline(void *p)
250 #ifdef HAVE_POSIX_MEMALIGN
254 free(*(void **) ((uintptr_t) p - MEM_ALIGN));
260 xasprintf(const char *format, ...)
265 va_start(args, format);
266 s = xvasprintf(format, args);
272 /* Similar to strlcpy() from OpenBSD, but it never reads more than 'size - 1'
273 * bytes from 'src' and doesn't return anything. */
275 ovs_strlcpy(char *dst, const char *src, size_t size)
278 size_t len = strnlen(src, size - 1);
279 memcpy(dst, src, len);
284 /* Copies 'src' to 'dst'. Reads no more than 'size - 1' bytes from 'src'.
285 * Always null-terminates 'dst' (if 'size' is nonzero), and writes a zero byte
286 * to every otherwise unused byte in 'dst'.
288 * Except for performance, the following call:
289 * ovs_strzcpy(dst, src, size);
290 * is equivalent to these two calls:
291 * memset(dst, '\0', size);
292 * ovs_strlcpy(dst, src, size);
294 * (Thus, ovs_strzcpy() is similar to strncpy() without some of the pitfalls.)
297 ovs_strzcpy(char *dst, const char *src, size_t size)
300 size_t len = strnlen(src, size - 1);
301 memcpy(dst, src, len);
302 memset(dst + len, '\0', size - len);
306 /* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
307 * nonzero, then it is formatted with ovs_retval_to_string() and appended to
308 * the message inside parentheses. Then, terminates with abort().
310 * This function is preferred to ovs_fatal() in a situation where it would make
311 * sense for a monitoring process to restart the daemon.
313 * 'format' should not end with a new-line, because this function will add one
316 ovs_abort(int err_no, const char *format, ...)
320 va_start(args, format);
321 ovs_abort_valist(err_no, format, args);
324 /* Same as ovs_abort() except that the arguments are supplied as a va_list. */
326 ovs_abort_valist(int err_no, const char *format, va_list args)
328 ovs_error_valist(err_no, format, args);
332 /* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
333 * nonzero, then it is formatted with ovs_retval_to_string() and appended to
334 * the message inside parentheses. Then, terminates with EXIT_FAILURE.
336 * 'format' should not end with a new-line, because this function will add one
339 ovs_fatal(int err_no, const char *format, ...)
343 va_start(args, format);
344 ovs_fatal_valist(err_no, format, args);
347 /* Same as ovs_fatal() except that the arguments are supplied as a va_list. */
349 ovs_fatal_valist(int err_no, const char *format, va_list args)
351 ovs_error_valist(err_no, format, args);
355 /* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
356 * nonzero, then it is formatted with ovs_retval_to_string() and appended to
357 * the message inside parentheses.
359 * 'format' should not end with a new-line, because this function will add one
362 ovs_error(int err_no, const char *format, ...)
366 va_start(args, format);
367 ovs_error_valist(err_no, format, args);
371 /* Same as ovs_error() except that the arguments are supplied as a va_list. */
373 ovs_error_valist(int err_no, const char *format, va_list args)
375 const char *subprogram_name = get_subprogram_name();
376 int save_errno = errno;
378 if (subprogram_name[0]) {
379 fprintf(stderr, "%s(%s): ", program_name, subprogram_name);
381 fprintf(stderr, "%s: ", program_name);
384 vfprintf(stderr, format, args);
386 fprintf(stderr, " (%s)", ovs_retval_to_string(err_no));
393 /* Many OVS functions return an int which is one of:
396 * - EOF: end of file (not necessarily an error; depends on the function called)
398 * Returns the appropriate human-readable string. The caller must copy the
399 * string if it wants to hold onto it, as the storage may be overwritten on
400 * subsequent function calls.
403 ovs_retval_to_string(int retval)
406 : retval == EOF ? "End of file"
407 : ovs_strerror(retval));
410 /* This function returns the string describing the error number in 'error'
411 * for POSIX platforms. For Windows, this function can be used for C library
412 * calls. For socket calls that are also used in Windows, use sock_strerror()
413 * instead. For WINAPI calls, look at ovs_lasterror_to_string(). */
415 ovs_strerror(int error)
417 enum { BUFSIZE = sizeof strerror_buffer_get()->s };
424 * strerror(0) varies among platforms:
430 * We want to provide a consistent result here because
431 * our testsuite has test cases which strictly matches
432 * log messages containing this string.
438 buffer = strerror_buffer_get()->s;
440 #if STRERROR_R_CHAR_P
441 /* GNU style strerror_r() might return an immutable static string, or it
442 * might write and return 'buffer', but in either case we can pass the
443 * returned string directly to the caller. */
444 s = strerror_r(error, buffer, BUFSIZE);
445 #else /* strerror_r() returns an int. */
447 if (strerror_r(error, buffer, BUFSIZE)) {
448 /* strerror_r() is only allowed to fail on ERANGE (because the buffer
449 * is too short). We don't check the actual failure reason because
450 * POSIX requires strerror_r() to return the error but old glibc
451 * (before 2.13) returns -1 and sets errno. */
452 snprintf(buffer, BUFSIZE, "Unknown error %d", error);
461 /* Sets global "program_name" and "program_version" variables. Should
462 * be called at the beginning of main() with "argv[0]" as the argument
465 * 'version' should contain the version of the caller's program. If 'version'
466 * is the same as the VERSION #define, the caller is assumed to be part of Open
467 * vSwitch. Otherwise, it is assumed to be an external program linking against
468 * the Open vSwitch libraries.
472 ovs_set_program_name(const char *argv0, const char *version)
476 size_t max_len = strlen(argv0) + 1;
478 SetErrorMode(GetErrorMode() | SEM_NOGPFAULTERRORBOX);
479 _set_output_format(_TWO_DIGIT_EXPONENT);
481 basename = xmalloc(max_len);
482 _splitpath_s(argv0, NULL, 0, NULL, 0, basename, max_len, NULL, 0);
484 const char *slash = strrchr(argv0, '/');
485 basename = xstrdup(slash ? slash + 1 : argv0);
488 assert_single_threaded();
490 /* Remove libtool prefix, if it is there */
491 if (strncmp(basename, "lt-", 3) == 0) {
492 char *tmp_name = basename;
493 basename = xstrdup(basename + 3);
496 program_name = basename;
498 free(program_version);
499 if (!strcmp(version, VERSION)) {
500 program_version = xasprintf("%s (Open vSwitch) "VERSION"\n",
503 program_version = xasprintf("%s %s\n"
504 "Open vSwitch Library "VERSION"\n",
505 program_name, version);
509 /* Returns the name of the currently running thread or process. */
511 get_subprogram_name(void)
513 const char *name = subprogram_name_get();
514 return name ? name : "";
517 /* Sets 'subprogram_name' as the name of the currently running thread or
518 * process. (This appears in log messages and may also be visible in system
519 * process listings and debuggers.) */
521 set_subprogram_name(const char *subprogram_name)
523 char *pname = xstrdup(subprogram_name ? subprogram_name : program_name);
524 free(subprogram_name_set(pname));
526 #if HAVE_GLIBC_PTHREAD_SETNAME_NP
527 pthread_setname_np(pthread_self(), pname);
528 #elif HAVE_NETBSD_PTHREAD_SETNAME_NP
529 pthread_setname_np(pthread_self(), "%s", pname);
530 #elif HAVE_PTHREAD_SET_NAME_NP
531 pthread_set_name_np(pthread_self(), pname);
535 /* Returns a pointer to a string describing the program version. The
536 * caller must not modify or free the returned string.
539 ovs_get_program_version(void)
541 return program_version;
544 /* Returns a pointer to a string describing the program name. The
545 * caller must not modify or free the returned string.
548 ovs_get_program_name(void)
553 /* Print the version information for the program. */
555 ovs_print_version(uint8_t min_ofp, uint8_t max_ofp)
557 printf("%s", program_version);
558 if (min_ofp || max_ofp) {
559 printf("OpenFlow versions %#x:%#x\n", min_ofp, max_ofp);
563 /* Writes the 'size' bytes in 'buf' to 'stream' as hex bytes arranged 16 per
564 * line. Numeric offsets are also included, starting at 'ofs' for the first
565 * byte in 'buf'. If 'ascii' is true then the corresponding ASCII characters
566 * are also rendered alongside. */
568 ovs_hex_dump(FILE *stream, const void *buf_, size_t size,
569 uintptr_t ofs, bool ascii)
571 const uint8_t *buf = buf_;
572 const size_t per_line = 16; /* Maximum bytes per line. */
576 size_t start, end, n;
579 /* Number of bytes on this line. */
580 start = ofs % per_line;
582 if (end - start > size)
587 fprintf(stream, "%08"PRIxMAX" ", (uintmax_t) ROUND_DOWN(ofs, per_line));
588 for (i = 0; i < start; i++)
589 fprintf(stream, " ");
591 fprintf(stream, "%02x%c",
592 buf[i - start], i == per_line / 2 - 1? '-' : ' ');
595 for (; i < per_line; i++)
596 fprintf(stream, " ");
597 fprintf(stream, "|");
598 for (i = 0; i < start; i++)
599 fprintf(stream, " ");
600 for (; i < end; i++) {
601 int c = buf[i - start];
602 putc(c >= 32 && c < 127 ? c : '.', stream);
604 for (; i < per_line; i++)
605 fprintf(stream, " ");
606 fprintf(stream, "|");
608 fprintf(stream, "\n");
617 str_to_int(const char *s, int base, int *i)
620 bool ok = str_to_llong(s, base, &ll);
626 str_to_long(const char *s, int base, long *li)
629 bool ok = str_to_llong(s, base, &ll);
635 str_to_llong(const char *s, int base, long long *x)
637 int save_errno = errno;
640 *x = strtoll(s, &tail, base);
641 if (errno == EINVAL || errno == ERANGE || tail == s || *tail != '\0') {
652 str_to_uint(const char *s, int base, unsigned int *u)
655 bool ok = str_to_llong(s, base, &ll);
656 if (!ok || ll < 0 || ll > UINT_MAX) {
665 /* Converts floating-point string 's' into a double. If successful, stores
666 * the double in '*d' and returns true; on failure, stores 0 in '*d' and
669 * Underflow (e.g. "1e-9999") is not considered an error, but overflow
670 * (e.g. "1e9999)" is. */
672 str_to_double(const char *s, double *d)
674 int save_errno = errno;
677 *d = strtod(s, &tail);
678 if (errno == EINVAL || (errno == ERANGE && *d != 0)
679 || tail == s || *tail != '\0') {
689 /* Returns the value of 'c' as a hexadecimal digit. */
694 case '0': case '1': case '2': case '3': case '4':
695 case '5': case '6': case '7': case '8': case '9':
721 /* Returns the integer value of the 'n' hexadecimal digits starting at 's', or
722 * UINTMAX_MAX if one of those "digits" is not really a hex digit. Sets '*ok'
723 * to true if the conversion succeeds or to false if a non-hex digit is
726 hexits_value(const char *s, size_t n, bool *ok)
732 for (i = 0; i < n; i++) {
733 int hexit = hexit_value(s[i]);
738 value = (value << 4) + hexit;
744 /* Parses the string in 's' as an integer in either hex or decimal format and
745 * puts the result right justified in the array 'valuep' that is 'field_width'
746 * big. If the string is in hex format, the value may be arbitrarily large;
747 * integers are limited to 64-bit values. (The rationale is that decimal is
748 * likely to represent a number and 64 bits is a reasonable maximum whereas
749 * hex could either be a number or a byte string.)
751 * On return 'tail' points to the first character in the string that was
752 * not parsed as part of the value. ERANGE is returned if the value is too
753 * large to fit in the given field. */
755 parse_int_string(const char *s, uint8_t *valuep, int field_width, char **tail)
757 unsigned long long int integer;
760 if (!strncmp(s, "0x", 2) || !strncmp(s, "0X", 2)) {
767 hexit_str = xmalloc(field_width * 2);
773 s += strspn(s, " \t\r\n");
774 hexit = hexits_value(s, 1, &ok);
776 *tail = CONST_CAST(char *, s);
780 if (hexit != 0 || len) {
781 if (DIV_ROUND_UP(len + 1, 2) > field_width) {
786 hexit_str[len] = hexit;
792 val_idx = field_width;
793 for (i = len - 1; i >= 0; i -= 2) {
795 valuep[val_idx] = hexit_str[i];
797 valuep[val_idx] += hexit_str[i - 1] << 4;
801 memset(valuep, 0, val_idx);
809 integer = strtoull(s, tail, 0);
814 for (i = field_width - 1; i >= 0; i--) {
825 /* Returns the current working directory as a malloc()'d string, or a null
826 * pointer if the current working directory cannot be determined. */
833 /* Get maximum path length or at least a reasonable estimate. */
835 path_max = pathconf(".", _PC_PATH_MAX);
839 size = (path_max < 0 ? 1024
840 : path_max > 10240 ? 10240
843 /* Get current working directory. */
845 char *buf = xmalloc(size);
846 if (getcwd(buf, size)) {
847 return xrealloc(buf, strlen(buf) + 1);
851 if (error != ERANGE) {
852 VLOG_WARN("getcwd failed (%s)", ovs_strerror(error));
861 all_slashes_name(const char *s)
863 return xstrdup(s[0] == '/' && s[1] == '/' && s[2] != '/' ? "//"
869 /* Returns the directory name portion of 'file_name' as a malloc()'d string,
870 * similar to the POSIX dirname() function but thread-safe. */
872 dir_name(const char *file_name)
874 size_t len = strlen(file_name);
875 while (len > 0 && file_name[len - 1] == '/') {
878 while (len > 0 && file_name[len - 1] != '/') {
881 while (len > 0 && file_name[len - 1] == '/') {
884 return len ? xmemdup0(file_name, len) : all_slashes_name(file_name);
887 /* Returns the file name portion of 'file_name' as a malloc()'d string,
888 * similar to the POSIX basename() function but thread-safe. */
890 base_name(const char *file_name)
894 end = strlen(file_name);
895 while (end > 0 && file_name[end - 1] == '/') {
900 return all_slashes_name(file_name);
904 while (start > 0 && file_name[start - 1] != '/') {
908 return xmemdup0(file_name + start, end - start);
912 /* If 'file_name' starts with '/', returns a copy of 'file_name'. Otherwise,
913 * returns an absolute path to 'file_name' considering it relative to 'dir',
914 * which itself must be absolute. 'dir' may be null or the empty string, in
915 * which case the current working directory is used.
917 * Returns a null pointer if 'dir' is null and getcwd() fails. */
919 abs_file_name(const char *dir, const char *file_name)
921 if (file_name[0] == '/') {
922 return xstrdup(file_name);
923 } else if (dir && dir[0]) {
924 char *separator = dir[strlen(dir) - 1] == '/' ? "" : "/";
925 return xasprintf("%s%s%s", dir, separator, file_name);
927 char *cwd = get_cwd();
929 char *abs_name = xasprintf("%s/%s", cwd, file_name);
938 /* Like readlink(), but returns the link name as a null-terminated string in
939 * allocated memory that the caller must eventually free (with free()).
940 * Returns NULL on error, in which case errno is set appropriately. */
942 xreadlink(const char *filename)
946 for (size = 64; ; size *= 2) {
947 char *buf = xmalloc(size);
948 ssize_t retval = readlink(filename, buf, size);
951 if (retval >= 0 && retval < size) {
964 /* Returns a version of 'filename' with symlinks in the final component
965 * dereferenced. This differs from realpath() in that:
967 * - 'filename' need not exist.
969 * - If 'filename' does exist as a symlink, its referent need not exist.
971 * - Only symlinks in the final component of 'filename' are dereferenced.
973 * For Windows platform, this function returns a string that has the same
974 * value as the passed string.
976 * The caller must eventually free the returned string (with free()). */
978 follow_symlinks(const char *filename)
985 fn = xstrdup(filename);
986 for (i = 0; i < 10; i++) {
990 if (lstat(fn, &s) != 0 || !S_ISLNK(s.st_mode)) {
994 linkname = xreadlink(fn);
996 VLOG_WARN("%s: readlink failed (%s)",
997 filename, ovs_strerror(errno));
1001 if (linkname[0] == '/') {
1002 /* Target of symlink is absolute so use it raw. */
1005 /* Target of symlink is relative so add to 'fn''s directory. */
1006 char *dir = dir_name(fn);
1008 if (!strcmp(dir, ".")) {
1011 char *separator = dir[strlen(dir) - 1] == '/' ? "" : "/";
1012 next_fn = xasprintf("%s%s%s", dir, separator, linkname);
1023 VLOG_WARN("%s: too many levels of symlinks", filename);
1026 return xstrdup(filename);
1029 /* Pass a value to this function if it is marked with
1030 * __attribute__((warn_unused_result)) and you genuinely want to ignore
1031 * its return value. (Note that every scalar type can be implicitly
1032 * converted to bool.) */
1033 void ignore(bool x OVS_UNUSED) { }
1035 /* Returns an appropriate delimiter for inserting just before the 0-based item
1036 * 'index' in a list that has 'total' items in it. */
1038 english_list_delimiter(size_t index, size_t total)
1040 return (index == 0 ? ""
1041 : index < total - 1 ? ", "
1042 : total > 2 ? ", and "
1046 /* Returns the number of trailing 0-bits in 'n'. Undefined if 'n' == 0. */
1047 #if __GNUC__ >= 4 || _MSC_VER
1048 /* Defined inline in util.h. */
1050 /* Returns the number of trailing 0-bits in 'n'. Undefined if 'n' == 0. */
1057 #define CTZ_STEP(X) \
1074 /* Returns the number of leading 0-bits in 'n'. Undefined if 'n' == 0. */
1076 raw_clz64(uint64_t n)
1081 #define CLZ_STEP(X) \
1099 #if NEED_COUNT_1BITS_8
1101 ((((X) & (1 << 0)) != 0) + \
1102 (((X) & (1 << 1)) != 0) + \
1103 (((X) & (1 << 2)) != 0) + \
1104 (((X) & (1 << 3)) != 0) + \
1105 (((X) & (1 << 4)) != 0) + \
1106 (((X) & (1 << 5)) != 0) + \
1107 (((X) & (1 << 6)) != 0) + \
1108 (((X) & (1 << 7)) != 0))
1109 #define INIT2(X) INIT1(X), INIT1((X) + 1)
1110 #define INIT4(X) INIT2(X), INIT2((X) + 2)
1111 #define INIT8(X) INIT4(X), INIT4((X) + 4)
1112 #define INIT16(X) INIT8(X), INIT8((X) + 8)
1113 #define INIT32(X) INIT16(X), INIT16((X) + 16)
1114 #define INIT64(X) INIT32(X), INIT32((X) + 32)
1116 const uint8_t count_1bits_8[256] = {
1117 INIT64(0), INIT64(64), INIT64(128), INIT64(192)
1121 /* Returns true if the 'n' bytes starting at 'p' are zeros. */
1123 is_all_zeros(const void *p_, size_t n)
1125 const uint8_t *p = p_;
1128 for (i = 0; i < n; i++) {
1136 /* Returns true if the 'n' bytes starting at 'p' are 0xff. */
1138 is_all_ones(const void *p_, size_t n)
1140 const uint8_t *p = p_;
1143 for (i = 0; i < n; i++) {
1151 /* Copies 'n_bits' bits starting from bit 'src_ofs' in 'src' to the 'n_bits'
1152 * starting from bit 'dst_ofs' in 'dst'. 'src' is 'src_len' bytes long and
1153 * 'dst' is 'dst_len' bytes long.
1155 * If you consider all of 'src' to be a single unsigned integer in network byte
1156 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1157 * with value 1 in src[src_len - 1], bit 1 is the bit with value 2, bit 2 is
1158 * the bit with value 4, ..., bit 8 is the bit with value 1 in src[src_len -
1159 * 2], and so on. Similarly for 'dst'.
1161 * Required invariants:
1162 * src_ofs + n_bits <= src_len * 8
1163 * dst_ofs + n_bits <= dst_len * 8
1164 * 'src' and 'dst' must not overlap.
1167 bitwise_copy(const void *src_, unsigned int src_len, unsigned int src_ofs,
1168 void *dst_, unsigned int dst_len, unsigned int dst_ofs,
1169 unsigned int n_bits)
1171 const uint8_t *src = src_;
1172 uint8_t *dst = dst_;
1174 src += src_len - (src_ofs / 8 + 1);
1177 dst += dst_len - (dst_ofs / 8 + 1);
1180 if (src_ofs == 0 && dst_ofs == 0) {
1181 unsigned int n_bytes = n_bits / 8;
1185 memcpy(dst, src, n_bytes);
1192 uint8_t mask = (1 << n_bits) - 1;
1193 *dst = (*dst & ~mask) | (*src & mask);
1196 while (n_bits > 0) {
1197 unsigned int max_copy = 8 - MAX(src_ofs, dst_ofs);
1198 unsigned int chunk = MIN(n_bits, max_copy);
1199 uint8_t mask = ((1 << chunk) - 1) << dst_ofs;
1202 *dst |= ((*src >> src_ofs) << dst_ofs) & mask;
1219 /* Zeros the 'n_bits' bits starting from bit 'dst_ofs' in 'dst'. 'dst' is
1220 * 'dst_len' bytes long.
1222 * If you consider all of 'dst' to be a single unsigned integer in network byte
1223 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1224 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1225 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1228 * Required invariant:
1229 * dst_ofs + n_bits <= dst_len * 8
1232 bitwise_zero(void *dst_, unsigned int dst_len, unsigned dst_ofs,
1233 unsigned int n_bits)
1235 uint8_t *dst = dst_;
1241 dst += dst_len - (dst_ofs / 8 + 1);
1245 unsigned int chunk = MIN(n_bits, 8 - dst_ofs);
1247 *dst &= ~(((1 << chunk) - 1) << dst_ofs);
1257 while (n_bits >= 8) {
1263 *dst &= ~((1 << n_bits) - 1);
1267 /* Sets to 1 all of the 'n_bits' bits starting from bit 'dst_ofs' in 'dst'.
1268 * 'dst' is 'dst_len' bytes long.
1270 * If you consider all of 'dst' to be a single unsigned integer in network byte
1271 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1272 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1273 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1276 * Required invariant:
1277 * dst_ofs + n_bits <= dst_len * 8
1280 bitwise_one(void *dst_, unsigned int dst_len, unsigned dst_ofs,
1281 unsigned int n_bits)
1283 uint8_t *dst = dst_;
1289 dst += dst_len - (dst_ofs / 8 + 1);
1293 unsigned int chunk = MIN(n_bits, 8 - dst_ofs);
1295 *dst |= ((1 << chunk) - 1) << dst_ofs;
1305 while (n_bits >= 8) {
1311 *dst |= (1 << n_bits) - 1;
1315 /* Scans the 'n_bits' bits starting from bit 'dst_ofs' in 'dst' for 1-bits.
1316 * Returns false if any 1-bits are found, otherwise true. 'dst' is 'dst_len'
1319 * If you consider all of 'dst' to be a single unsigned integer in network byte
1320 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1321 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1322 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1325 * Required invariant:
1326 * dst_ofs + n_bits <= dst_len * 8
1329 bitwise_is_all_zeros(const void *p_, unsigned int len, unsigned int ofs,
1330 unsigned int n_bits)
1332 const uint8_t *p = p_;
1338 p += len - (ofs / 8 + 1);
1342 unsigned int chunk = MIN(n_bits, 8 - ofs);
1344 if (*p & (((1 << chunk) - 1) << ofs)) {
1356 while (n_bits >= 8) {
1364 if (n_bits && *p & ((1 << n_bits) - 1)) {
1371 /* Scans the bits in 'p' that have bit offsets 'start' (inclusive) through
1372 * 'end' (exclusive) for the first bit with value 'target'. If one is found,
1373 * returns its offset, otherwise 'end'. 'p' is 'len' bytes long.
1375 * If you consider all of 'p' to be a single unsigned integer in network byte
1376 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1377 * with value 1 in p[len - 1], bit 1 is the bit with value 2, bit 2 is the bit
1378 * with value 4, ..., bit 8 is the bit with value 1 in p[len - 2], and so on.
1380 * Required invariant:
1384 bitwise_scan(const void *p, unsigned int len, bool target, unsigned int start,
1389 for (ofs = start; ofs < end; ofs++) {
1390 if (bitwise_get_bit(p, len, ofs) == target) {
1397 /* Scans the bits in 'p' that have bit offsets 'start' (inclusive) through
1398 * 'end' (exclusive) for the first bit with value 'target', in reverse order.
1399 * If one is found, returns its offset, otherwise 'end'. 'p' is 'len' bytes
1402 * If you consider all of 'p' to be a single unsigned integer in network byte
1403 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1404 * with value 1 in p[len - 1], bit 1 is the bit with value 2, bit 2 is the bit
1405 * with value 4, ..., bit 8 is the bit with value 1 in p[len - 2], and so on.
1407 * To scan an entire bit array in reverse order, specify start == len * 8 - 1
1408 * and end == -1, in which case the return value is nonnegative if successful
1409 * and -1 if no 'target' match is found.
1411 * Required invariant:
1415 bitwise_rscan(const void *p, unsigned int len, bool target, int start, int end)
1417 const uint8_t *s = p;
1418 int start_byte = len - (start / 8 + 1);
1419 int end_byte = len - (end / 8 + 1);
1424 /* Find the target in the start_byte from starting offset */
1425 ofs_byte = start_byte;
1426 the_byte = s[ofs_byte];
1427 for (ofs = start % 8; ofs >= 0; ofs--) {
1428 if (((the_byte & (1u << ofs)) != 0) == target) {
1433 /* Target not found in start byte, continue searching byte by byte */
1434 for (ofs_byte = start_byte + 1; ofs_byte <= end_byte; ofs_byte++) {
1435 if ((target && s[ofs_byte])
1436 || (!target && (s[ofs_byte] != 0xff))) {
1440 if (ofs_byte > end_byte) {
1443 the_byte = s[ofs_byte];
1444 /* Target is in the_byte, find it bit by bit */
1445 for (ofs = 7; ofs >= 0; ofs--) {
1446 if (((the_byte & (1u << ofs)) != 0) == target) {
1451 int ret = (len - ofs_byte) * 8 - (8 - ofs);
1458 /* Copies the 'n_bits' low-order bits of 'value' into the 'n_bits' bits
1459 * starting at bit 'dst_ofs' in 'dst', which is 'dst_len' bytes long.
1461 * If you consider all of 'dst' to be a single unsigned integer in network byte
1462 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1463 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1464 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1467 * Required invariants:
1468 * dst_ofs + n_bits <= dst_len * 8
1472 bitwise_put(uint64_t value,
1473 void *dst, unsigned int dst_len, unsigned int dst_ofs,
1474 unsigned int n_bits)
1476 ovs_be64 n_value = htonll(value);
1477 bitwise_copy(&n_value, sizeof n_value, 0,
1478 dst, dst_len, dst_ofs,
1482 /* Returns the value of the 'n_bits' bits starting at bit 'src_ofs' in 'src',
1483 * which is 'src_len' bytes long.
1485 * If you consider all of 'src' to be a single unsigned integer in network byte
1486 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1487 * with value 1 in src[src_len - 1], bit 1 is the bit with value 2, bit 2 is
1488 * the bit with value 4, ..., bit 8 is the bit with value 1 in src[src_len -
1491 * Required invariants:
1492 * src_ofs + n_bits <= src_len * 8
1496 bitwise_get(const void *src, unsigned int src_len,
1497 unsigned int src_ofs, unsigned int n_bits)
1499 ovs_be64 value = htonll(0);
1501 bitwise_copy(src, src_len, src_ofs,
1502 &value, sizeof value, 0,
1504 return ntohll(value);
1507 /* Returns the value of the bit with offset 'ofs' in 'src', which is 'len'
1510 * If you consider all of 'src' to be a single unsigned integer in network byte
1511 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1512 * with value 1 in src[len - 1], bit 1 is the bit with value 2, bit 2 is the
1513 * bit with value 4, ..., bit 8 is the bit with value 1 in src[len - 2], and so
1516 * Required invariants:
1520 bitwise_get_bit(const void *src_, unsigned int len, unsigned int ofs)
1522 const uint8_t *src = src_;
1524 return (src[len - (ofs / 8 + 1)] & (1u << (ofs % 8))) != 0;
1527 /* Sets the bit with offset 'ofs' in 'dst', which is 'len' bytes long, to 0.
1529 * If you consider all of 'dst' to be a single unsigned integer in network byte
1530 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1531 * with value 1 in dst[len - 1], bit 1 is the bit with value 2, bit 2 is the
1532 * bit with value 4, ..., bit 8 is the bit with value 1 in dst[len - 2], and so
1535 * Required invariants:
1539 bitwise_put0(void *dst_, unsigned int len, unsigned int ofs)
1541 uint8_t *dst = dst_;
1543 dst[len - (ofs / 8 + 1)] &= ~(1u << (ofs % 8));
1546 /* Sets the bit with offset 'ofs' in 'dst', which is 'len' bytes long, to 1.
1548 * If you consider all of 'dst' to be a single unsigned integer in network byte
1549 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1550 * with value 1 in dst[len - 1], bit 1 is the bit with value 2, bit 2 is the
1551 * bit with value 4, ..., bit 8 is the bit with value 1 in dst[len - 2], and so
1554 * Required invariants:
1558 bitwise_put1(void *dst_, unsigned int len, unsigned int ofs)
1560 uint8_t *dst = dst_;
1562 dst[len - (ofs / 8 + 1)] |= 1u << (ofs % 8);
1565 /* Sets the bit with offset 'ofs' in 'dst', which is 'len' bytes long, to 'b'.
1567 * If you consider all of 'dst' to be a single unsigned integer in network byte
1568 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1569 * with value 1 in dst[len - 1], bit 1 is the bit with value 2, bit 2 is the
1570 * bit with value 4, ..., bit 8 is the bit with value 1 in dst[len - 2], and so
1573 * Required invariants:
1577 bitwise_put_bit(void *dst, unsigned int len, unsigned int ofs, bool b)
1580 bitwise_put1(dst, len, ofs);
1582 bitwise_put0(dst, len, ofs);
1586 /* Flips the bit with offset 'ofs' in 'dst', which is 'len' bytes long.
1588 * If you consider all of 'dst' to be a single unsigned integer in network byte
1589 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1590 * with value 1 in dst[len - 1], bit 1 is the bit with value 2, bit 2 is the
1591 * bit with value 4, ..., bit 8 is the bit with value 1 in dst[len - 2], and so
1594 * Required invariants:
1598 bitwise_toggle_bit(void *dst_, unsigned int len, unsigned int ofs)
1600 uint8_t *dst = dst_;
1602 dst[len - (ofs / 8 + 1)] ^= 1u << (ofs % 8);
1623 skip_spaces(const char *s)
1625 while (isspace((unsigned char) *s)) {
1632 scan_int(const char *s, const struct scan_spec *spec, int base, va_list *args)
1634 const char *start = s;
1639 negative = *s == '-';
1640 s += *s == '-' || *s == '+';
1642 if ((!base || base == 16) && *s == '0' && (s[1] == 'x' || s[1] == 'X')) {
1646 base = *s == '0' ? 8 : 10;
1649 if (s - start >= spec->width) {
1655 while (s - start < spec->width) {
1656 int digit = hexit_value(*s);
1658 if (digit < 0 || digit >= base) {
1661 value = value * base + digit;
1673 switch (spec->type) {
1677 *va_arg(*args, char *) = value;
1680 *va_arg(*args, short int *) = value;
1683 *va_arg(*args, int *) = value;
1686 *va_arg(*args, long int *) = value;
1689 *va_arg(*args, long long int *) = value;
1692 *va_arg(*args, intmax_t *) = value;
1694 case SCAN_PTRDIFF_T:
1695 *va_arg(*args, ptrdiff_t *) = value;
1698 *va_arg(*args, size_t *) = value;
1705 skip_digits(const char *s)
1707 while (*s >= '0' && *s <= '9') {
1714 scan_float(const char *s, const struct scan_spec *spec, va_list *args)
1716 const char *start = s;
1722 s += *s == '+' || *s == '-';
1725 s = skip_digits(s + 1);
1727 if (*s == 'e' || *s == 'E') {
1729 s += *s == '+' || *s == '-';
1733 if (s - start > spec->width) {
1734 s = start + spec->width;
1737 copy = xmemdup0(start, s - start);
1738 value = strtold(copy, &tail);
1745 switch (spec->type) {
1749 *va_arg(*args, float *) = value;
1752 *va_arg(*args, double *) = value;
1755 *va_arg(*args, long double *) = value;
1761 case SCAN_PTRDIFF_T:
1769 scan_output_string(const struct scan_spec *spec,
1770 const char *s, size_t n,
1773 if (spec->type != SCAN_DISCARD) {
1774 char *out = va_arg(*args, char *);
1781 scan_string(const char *s, const struct scan_spec *spec, va_list *args)
1785 for (n = 0; n < spec->width; n++) {
1786 if (!s[n] || isspace((unsigned char) s[n])) {
1794 scan_output_string(spec, s, n, args);
1799 parse_scanset(const char *p_, unsigned long *set, bool *complemented)
1801 const uint8_t *p = (const uint8_t *) p_;
1803 *complemented = *p == '^';
1807 bitmap_set1(set, ']');
1811 while (*p && *p != ']') {
1812 if (p[1] == '-' && p[2] != ']' && p[2] > *p) {
1813 bitmap_set_multiple(set, *p, p[2] - *p + 1, true);
1816 bitmap_set1(set, *p++);
1822 return (const char *) p;
1826 scan_set(const char *s, const struct scan_spec *spec, const char **pp,
1829 unsigned long set[BITMAP_N_LONGS(UCHAR_MAX + 1)];
1833 /* Parse the scan set. */
1834 memset(set, 0, sizeof set);
1835 *pp = parse_scanset(*pp, set, &complemented);
1837 /* Parse the data. */
1840 && bitmap_is_set(set, (unsigned char) s[n]) == !complemented
1841 && n < spec->width) {
1847 scan_output_string(spec, s, n, args);
1852 scan_chars(const char *s, const struct scan_spec *spec, va_list *args)
1854 unsigned int n = spec->width == UINT_MAX ? 1 : spec->width;
1856 if (strlen(s) < n) {
1859 if (spec->type != SCAN_DISCARD) {
1860 memcpy(va_arg(*args, char *), s, n);
1866 ovs_scan__(const char *s, int *n, const char *format, va_list *args)
1868 const char *const start = s;
1873 while (*p != '\0') {
1874 struct scan_spec spec;
1875 unsigned char c = *p++;
1881 } else if (c != '%') {
1887 } else if (*p == '%') {
1895 /* Parse '*' flag. */
1896 discard = *p == '*';
1899 /* Parse field width. */
1901 while (*p >= '0' && *p <= '9') {
1902 spec.width = spec.width * 10 + (*p++ - '0');
1904 if (spec.width == 0) {
1905 spec.width = UINT_MAX;
1908 /* Parse type modifier. */
1912 spec.type = SCAN_CHAR;
1915 spec.type = SCAN_SHORT;
1921 spec.type = SCAN_INTMAX_T;
1927 spec.type = SCAN_LLONG;
1930 spec.type = SCAN_LONG;
1937 spec.type = SCAN_LLONG;
1942 spec.type = SCAN_PTRDIFF_T;
1947 spec.type = SCAN_SIZE_T;
1952 spec.type = SCAN_INT;
1957 spec.type = SCAN_DISCARD;
1961 if (c != 'c' && c != 'n' && c != '[') {
1966 s = scan_int(s, &spec, 10, args);
1970 s = scan_int(s, &spec, 0, args);
1974 s = scan_int(s, &spec, 8, args);
1978 s = scan_int(s, &spec, 10, args);
1983 s = scan_int(s, &spec, 16, args);
1991 s = scan_float(s, &spec, args);
1995 s = scan_string(s, &spec, args);
1999 s = scan_set(s, &spec, &p, args);
2003 s = scan_chars(s, &spec, args);
2007 if (spec.type != SCAN_DISCARD) {
2008 *va_arg(*args, int *) = s - start;
2026 /* This is an implementation of the standard sscanf() function, with the
2027 * following exceptions:
2029 * - It returns true if the entire format was successfully scanned and
2030 * converted, false if any conversion failed.
2032 * - The standard doesn't define sscanf() behavior when an out-of-range value
2033 * is scanned, e.g. if a "%"PRIi8 conversion scans "-1" or "0x1ff". Some
2034 * implementations consider this an error and stop scanning. This
2035 * implementation never considers an out-of-range value an error; instead,
2036 * it stores the least-significant bits of the converted value in the
2037 * destination, e.g. the value 255 for both examples earlier.
2039 * - Only single-byte characters are supported, that is, the 'l' modifier
2040 * on %s, %[, and %c is not supported. The GNU extension 'a' modifier is
2041 * also not supported.
2043 * - %p is not supported.
2046 ovs_scan(const char *s, const char *format, ...)
2051 va_start(args, format);
2052 res = ovs_scan__(s, NULL, format, &args);
2058 * This function is similar to ovs_scan(), with an extra parameter `n` added to
2059 * return the number of scanned characters.
2062 ovs_scan_len(const char *s, int *n, const char *format, ...)
2068 va_start(args, format);
2069 success = ovs_scan__(s + *n, &n1, format, &args);
2078 xsleep(unsigned int seconds)
2080 ovsrcu_quiesce_start();
2082 Sleep(seconds * 1000);
2086 ovsrcu_quiesce_end();
2089 /* Determine whether standard output is a tty or not. This is useful to decide
2090 * whether to use color output or not when --color option for utilities is set
2094 is_stdout_a_tty(void)
2096 char const *t = getenv("TERM");
2097 return (isatty(STDOUT_FILENO) && t && strcmp(t, "dumb") != 0);
2103 ovs_format_message(int error)
2105 enum { BUFSIZE = sizeof strerror_buffer_get()->s };
2106 char *buffer = strerror_buffer_get()->s;
2109 /* See ovs_strerror */
2113 FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
2114 NULL, error, 0, buffer, BUFSIZE, NULL);
2118 /* Returns a null-terminated string that explains the last error.
2119 * Use this function to get the error string for WINAPI calls. */
2121 ovs_lasterror_to_string(void)
2123 return ovs_format_message(GetLastError());
2127 ftruncate(int fd, off_t length)
2131 error = _chsize_s(fd, length);
2138 OVS_CONSTRUCTOR(winsock_start) {
2142 error = WSAStartup(MAKEWORD(2, 2), &wsaData);
2144 VLOG_FATAL("WSAStartup failed: %s", sock_strerror(sock_errno()));