2 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015 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 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 };
418 * strerror(0) varies among platforms:
424 * We want to provide a consistent result here because
425 * our testsuite has test cases which strictly matches
426 * log messages containing this string.
432 buffer = strerror_buffer_get()->s;
434 #if STRERROR_R_CHAR_P
435 /* GNU style strerror_r() might return an immutable static string, or it
436 * might write and return 'buffer', but in either case we can pass the
437 * returned string directly to the caller. */
438 s = strerror_r(error, buffer, BUFSIZE);
439 #else /* strerror_r() returns an int. */
441 if (strerror_r(error, buffer, BUFSIZE)) {
442 /* strerror_r() is only allowed to fail on ERANGE (because the buffer
443 * is too short). We don't check the actual failure reason because
444 * POSIX requires strerror_r() to return the error but old glibc
445 * (before 2.13) returns -1 and sets errno. */
446 snprintf(buffer, BUFSIZE, "Unknown error %d", error);
455 /* Sets global "program_name" and "program_version" variables. Should
456 * be called at the beginning of main() with "argv[0]" as the argument
459 * 'version' should contain the version of the caller's program. If 'version'
460 * is the same as the VERSION #define, the caller is assumed to be part of Open
461 * vSwitch. Otherwise, it is assumed to be an external program linking against
462 * the Open vSwitch libraries.
466 ovs_set_program_name(const char *argv0, const char *version)
470 size_t max_len = strlen(argv0) + 1;
472 SetErrorMode(GetErrorMode() | SEM_NOGPFAULTERRORBOX);
473 _set_output_format(_TWO_DIGIT_EXPONENT);
475 basename = xmalloc(max_len);
476 _splitpath_s(argv0, NULL, 0, NULL, 0, basename, max_len, NULL, 0);
478 const char *slash = strrchr(argv0, '/');
479 basename = xstrdup(slash ? slash + 1 : argv0);
482 assert_single_threaded();
484 /* Remove libtool prefix, if it is there */
485 if (strncmp(basename, "lt-", 3) == 0) {
486 char *tmp_name = basename;
487 basename = xstrdup(basename + 3);
490 program_name = basename;
492 free(program_version);
493 if (!strcmp(version, VERSION)) {
494 program_version = xasprintf("%s (Open vSwitch) "VERSION"\n",
497 program_version = xasprintf("%s %s\n"
498 "Open vSwitch Library "VERSION"\n",
499 program_name, version);
503 /* Returns the name of the currently running thread or process. */
505 get_subprogram_name(void)
507 const char *name = subprogram_name_get();
508 return name ? name : "";
511 /* Sets 'subprogram_name' as the name of the currently running thread or
512 * process. (This appears in log messages and may also be visible in system
513 * process listings and debuggers.) */
515 set_subprogram_name(const char *subprogram_name)
517 char *pname = xstrdup(subprogram_name ? subprogram_name : program_name);
518 free(subprogram_name_set(pname));
520 #if HAVE_GLIBC_PTHREAD_SETNAME_NP
521 pthread_setname_np(pthread_self(), pname);
522 #elif HAVE_NETBSD_PTHREAD_SETNAME_NP
523 pthread_setname_np(pthread_self(), "%s", pname);
524 #elif HAVE_PTHREAD_SET_NAME_NP
525 pthread_set_name_np(pthread_self(), pname);
529 /* Returns a pointer to a string describing the program version. The
530 * caller must not modify or free the returned string.
533 ovs_get_program_version(void)
535 return program_version;
538 /* Returns a pointer to a string describing the program name. The
539 * caller must not modify or free the returned string.
542 ovs_get_program_name(void)
547 /* Print the version information for the program. */
549 ovs_print_version(uint8_t min_ofp, uint8_t max_ofp)
551 printf("%s", program_version);
552 if (min_ofp || max_ofp) {
553 printf("OpenFlow versions %#x:%#x\n", min_ofp, max_ofp);
557 /* Writes the 'size' bytes in 'buf' to 'stream' as hex bytes arranged 16 per
558 * line. Numeric offsets are also included, starting at 'ofs' for the first
559 * byte in 'buf'. If 'ascii' is true then the corresponding ASCII characters
560 * are also rendered alongside. */
562 ovs_hex_dump(FILE *stream, const void *buf_, size_t size,
563 uintptr_t ofs, bool ascii)
565 const uint8_t *buf = buf_;
566 const size_t per_line = 16; /* Maximum bytes per line. */
570 size_t start, end, n;
573 /* Number of bytes on this line. */
574 start = ofs % per_line;
576 if (end - start > size)
581 fprintf(stream, "%08"PRIxMAX" ", (uintmax_t) ROUND_DOWN(ofs, per_line));
582 for (i = 0; i < start; i++)
583 fprintf(stream, " ");
585 fprintf(stream, "%02x%c",
586 buf[i - start], i == per_line / 2 - 1? '-' : ' ');
589 for (; i < per_line; i++)
590 fprintf(stream, " ");
591 fprintf(stream, "|");
592 for (i = 0; i < start; i++)
593 fprintf(stream, " ");
594 for (; i < end; i++) {
595 int c = buf[i - start];
596 putc(c >= 32 && c < 127 ? c : '.', stream);
598 for (; i < per_line; i++)
599 fprintf(stream, " ");
600 fprintf(stream, "|");
602 fprintf(stream, "\n");
611 str_to_int(const char *s, int base, int *i)
614 bool ok = str_to_llong(s, base, &ll);
620 str_to_long(const char *s, int base, long *li)
623 bool ok = str_to_llong(s, base, &ll);
629 str_to_llong(const char *s, int base, long long *x)
631 int save_errno = errno;
634 *x = strtoll(s, &tail, base);
635 if (errno == EINVAL || errno == ERANGE || tail == s || *tail != '\0') {
646 str_to_uint(const char *s, int base, unsigned int *u)
649 bool ok = str_to_llong(s, base, &ll);
650 if (!ok || ll < 0 || ll > UINT_MAX) {
659 /* Converts floating-point string 's' into a double. If successful, stores
660 * the double in '*d' and returns true; on failure, stores 0 in '*d' and
663 * Underflow (e.g. "1e-9999") is not considered an error, but overflow
664 * (e.g. "1e9999)" is. */
666 str_to_double(const char *s, double *d)
668 int save_errno = errno;
671 *d = strtod(s, &tail);
672 if (errno == EINVAL || (errno == ERANGE && *d != 0)
673 || tail == s || *tail != '\0') {
683 /* Returns the value of 'c' as a hexadecimal digit. */
688 case '0': case '1': case '2': case '3': case '4':
689 case '5': case '6': case '7': case '8': case '9':
715 /* Returns the integer value of the 'n' hexadecimal digits starting at 's', or
716 * UINTMAX_MAX if one of those "digits" is not really a hex digit. Sets '*ok'
717 * to true if the conversion succeeds or to false if a non-hex digit is
720 hexits_value(const char *s, size_t n, bool *ok)
726 for (i = 0; i < n; i++) {
727 int hexit = hexit_value(s[i]);
732 value = (value << 4) + hexit;
738 /* Parses the string in 's' as an integer in either hex or decimal format and
739 * puts the result right justified in the array 'valuep' that is 'field_width'
740 * big. If the string is in hex format, the value may be arbitrarily large;
741 * integers are limited to 64-bit values. (The rationale is that decimal is
742 * likely to represent a number and 64 bits is a reasonable maximum whereas
743 * hex could either be a number or a byte string.)
745 * On return 'tail' points to the first character in the string that was
746 * not parsed as part of the value. ERANGE is returned if the value is too
747 * large to fit in the given field. */
749 parse_int_string(const char *s, uint8_t *valuep, int field_width, char **tail)
751 unsigned long long int integer;
754 if (!strncmp(s, "0x", 2) || !strncmp(s, "0X", 2)) {
761 hexit_str = xmalloc(field_width * 2);
767 s += strspn(s, " \t\r\n");
768 hexit = hexits_value(s, 1, &ok);
770 *tail = CONST_CAST(char *, s);
774 if (hexit != 0 || len) {
775 if (DIV_ROUND_UP(len + 1, 2) > field_width) {
780 hexit_str[len] = hexit;
786 val_idx = field_width;
787 for (i = len - 1; i >= 0; i -= 2) {
789 valuep[val_idx] = hexit_str[i];
791 valuep[val_idx] += hexit_str[i - 1] << 4;
795 memset(valuep, 0, val_idx);
803 integer = strtoull(s, tail, 0);
808 for (i = field_width - 1; i >= 0; i--) {
819 /* Returns the current working directory as a malloc()'d string, or a null
820 * pointer if the current working directory cannot be determined. */
827 /* Get maximum path length or at least a reasonable estimate. */
829 path_max = pathconf(".", _PC_PATH_MAX);
833 size = (path_max < 0 ? 1024
834 : path_max > 10240 ? 10240
837 /* Get current working directory. */
839 char *buf = xmalloc(size);
840 if (getcwd(buf, size)) {
841 return xrealloc(buf, strlen(buf) + 1);
845 if (error != ERANGE) {
846 VLOG_WARN("getcwd failed (%s)", ovs_strerror(error));
855 all_slashes_name(const char *s)
857 return xstrdup(s[0] == '/' && s[1] == '/' && s[2] != '/' ? "//"
863 /* Returns the directory name portion of 'file_name' as a malloc()'d string,
864 * similar to the POSIX dirname() function but thread-safe. */
866 dir_name(const char *file_name)
868 size_t len = strlen(file_name);
869 while (len > 0 && file_name[len - 1] == '/') {
872 while (len > 0 && file_name[len - 1] != '/') {
875 while (len > 0 && file_name[len - 1] == '/') {
878 return len ? xmemdup0(file_name, len) : all_slashes_name(file_name);
881 /* Returns the file name portion of 'file_name' as a malloc()'d string,
882 * similar to the POSIX basename() function but thread-safe. */
884 base_name(const char *file_name)
888 end = strlen(file_name);
889 while (end > 0 && file_name[end - 1] == '/') {
894 return all_slashes_name(file_name);
898 while (start > 0 && file_name[start - 1] != '/') {
902 return xmemdup0(file_name + start, end - start);
906 /* If 'file_name' starts with '/', returns a copy of 'file_name'. Otherwise,
907 * returns an absolute path to 'file_name' considering it relative to 'dir',
908 * which itself must be absolute. 'dir' may be null or the empty string, in
909 * which case the current working directory is used.
911 * Returns a null pointer if 'dir' is null and getcwd() fails. */
913 abs_file_name(const char *dir, const char *file_name)
915 if (file_name[0] == '/') {
916 return xstrdup(file_name);
917 } else if (dir && dir[0]) {
918 char *separator = dir[strlen(dir) - 1] == '/' ? "" : "/";
919 return xasprintf("%s%s%s", dir, separator, file_name);
921 char *cwd = get_cwd();
923 char *abs_name = xasprintf("%s/%s", cwd, file_name);
932 /* Like readlink(), but returns the link name as a null-terminated string in
933 * allocated memory that the caller must eventually free (with free()).
934 * Returns NULL on error, in which case errno is set appropriately. */
936 xreadlink(const char *filename)
940 for (size = 64; ; size *= 2) {
941 char *buf = xmalloc(size);
942 ssize_t retval = readlink(filename, buf, size);
945 if (retval >= 0 && retval < size) {
958 /* Returns a version of 'filename' with symlinks in the final component
959 * dereferenced. This differs from realpath() in that:
961 * - 'filename' need not exist.
963 * - If 'filename' does exist as a symlink, its referent need not exist.
965 * - Only symlinks in the final component of 'filename' are dereferenced.
967 * For Windows platform, this function returns a string that has the same
968 * value as the passed string.
970 * The caller must eventually free the returned string (with free()). */
972 follow_symlinks(const char *filename)
979 fn = xstrdup(filename);
980 for (i = 0; i < 10; i++) {
984 if (lstat(fn, &s) != 0 || !S_ISLNK(s.st_mode)) {
988 linkname = xreadlink(fn);
990 VLOG_WARN("%s: readlink failed (%s)",
991 filename, ovs_strerror(errno));
995 if (linkname[0] == '/') {
996 /* Target of symlink is absolute so use it raw. */
999 /* Target of symlink is relative so add to 'fn''s directory. */
1000 char *dir = dir_name(fn);
1002 if (!strcmp(dir, ".")) {
1005 char *separator = dir[strlen(dir) - 1] == '/' ? "" : "/";
1006 next_fn = xasprintf("%s%s%s", dir, separator, linkname);
1017 VLOG_WARN("%s: too many levels of symlinks", filename);
1020 return xstrdup(filename);
1023 /* Pass a value to this function if it is marked with
1024 * __attribute__((warn_unused_result)) and you genuinely want to ignore
1025 * its return value. (Note that every scalar type can be implicitly
1026 * converted to bool.) */
1027 void ignore(bool x OVS_UNUSED) { }
1029 /* Returns an appropriate delimiter for inserting just before the 0-based item
1030 * 'index' in a list that has 'total' items in it. */
1032 english_list_delimiter(size_t index, size_t total)
1034 return (index == 0 ? ""
1035 : index < total - 1 ? ", "
1036 : total > 2 ? ", and "
1040 /* Returns the number of trailing 0-bits in 'n'. Undefined if 'n' == 0. */
1041 #if __GNUC__ >= 4 || _MSC_VER
1042 /* Defined inline in util.h. */
1044 /* Returns the number of trailing 0-bits in 'n'. Undefined if 'n' == 0. */
1051 #define CTZ_STEP(X) \
1068 /* Returns the number of leading 0-bits in 'n'. Undefined if 'n' == 0. */
1070 raw_clz64(uint64_t n)
1075 #define CLZ_STEP(X) \
1093 #if NEED_COUNT_1BITS_8
1095 ((((X) & (1 << 0)) != 0) + \
1096 (((X) & (1 << 1)) != 0) + \
1097 (((X) & (1 << 2)) != 0) + \
1098 (((X) & (1 << 3)) != 0) + \
1099 (((X) & (1 << 4)) != 0) + \
1100 (((X) & (1 << 5)) != 0) + \
1101 (((X) & (1 << 6)) != 0) + \
1102 (((X) & (1 << 7)) != 0))
1103 #define INIT2(X) INIT1(X), INIT1((X) + 1)
1104 #define INIT4(X) INIT2(X), INIT2((X) + 2)
1105 #define INIT8(X) INIT4(X), INIT4((X) + 4)
1106 #define INIT16(X) INIT8(X), INIT8((X) + 8)
1107 #define INIT32(X) INIT16(X), INIT16((X) + 16)
1108 #define INIT64(X) INIT32(X), INIT32((X) + 32)
1110 const uint8_t count_1bits_8[256] = {
1111 INIT64(0), INIT64(64), INIT64(128), INIT64(192)
1115 /* Returns true if the 'n' bytes starting at 'p' are zeros. */
1117 is_all_zeros(const void *p_, size_t n)
1119 const uint8_t *p = p_;
1122 for (i = 0; i < n; i++) {
1130 /* Returns true if the 'n' bytes starting at 'p' are 0xff. */
1132 is_all_ones(const void *p_, size_t n)
1134 const uint8_t *p = p_;
1137 for (i = 0; i < n; i++) {
1145 /* Copies 'n_bits' bits starting from bit 'src_ofs' in 'src' to the 'n_bits'
1146 * starting from bit 'dst_ofs' in 'dst'. 'src' is 'src_len' bytes long and
1147 * 'dst' is 'dst_len' bytes long.
1149 * If you consider all of 'src' to be a single unsigned integer in network byte
1150 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1151 * with value 1 in src[src_len - 1], bit 1 is the bit with value 2, bit 2 is
1152 * the bit with value 4, ..., bit 8 is the bit with value 1 in src[src_len -
1153 * 2], and so on. Similarly for 'dst'.
1155 * Required invariants:
1156 * src_ofs + n_bits <= src_len * 8
1157 * dst_ofs + n_bits <= dst_len * 8
1158 * 'src' and 'dst' must not overlap.
1161 bitwise_copy(const void *src_, unsigned int src_len, unsigned int src_ofs,
1162 void *dst_, unsigned int dst_len, unsigned int dst_ofs,
1163 unsigned int n_bits)
1165 const uint8_t *src = src_;
1166 uint8_t *dst = dst_;
1168 src += src_len - (src_ofs / 8 + 1);
1171 dst += dst_len - (dst_ofs / 8 + 1);
1174 if (src_ofs == 0 && dst_ofs == 0) {
1175 unsigned int n_bytes = n_bits / 8;
1179 memcpy(dst, src, n_bytes);
1186 uint8_t mask = (1 << n_bits) - 1;
1187 *dst = (*dst & ~mask) | (*src & mask);
1190 while (n_bits > 0) {
1191 unsigned int max_copy = 8 - MAX(src_ofs, dst_ofs);
1192 unsigned int chunk = MIN(n_bits, max_copy);
1193 uint8_t mask = ((1 << chunk) - 1) << dst_ofs;
1196 *dst |= ((*src >> src_ofs) << dst_ofs) & mask;
1213 /* Zeros the 'n_bits' bits starting from bit 'dst_ofs' in 'dst'. 'dst' is
1214 * 'dst_len' bytes long.
1216 * If you consider all of 'dst' to be a single unsigned integer in network byte
1217 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1218 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1219 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1222 * Required invariant:
1223 * dst_ofs + n_bits <= dst_len * 8
1226 bitwise_zero(void *dst_, unsigned int dst_len, unsigned dst_ofs,
1227 unsigned int n_bits)
1229 uint8_t *dst = dst_;
1235 dst += dst_len - (dst_ofs / 8 + 1);
1239 unsigned int chunk = MIN(n_bits, 8 - dst_ofs);
1241 *dst &= ~(((1 << chunk) - 1) << dst_ofs);
1251 while (n_bits >= 8) {
1257 *dst &= ~((1 << n_bits) - 1);
1261 /* Sets to 1 all of the 'n_bits' bits starting from bit 'dst_ofs' in 'dst'.
1262 * 'dst' is 'dst_len' bytes long.
1264 * If you consider all of 'dst' to be a single unsigned integer in network byte
1265 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1266 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1267 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1270 * Required invariant:
1271 * dst_ofs + n_bits <= dst_len * 8
1274 bitwise_one(void *dst_, unsigned int dst_len, unsigned dst_ofs,
1275 unsigned int n_bits)
1277 uint8_t *dst = dst_;
1283 dst += dst_len - (dst_ofs / 8 + 1);
1287 unsigned int chunk = MIN(n_bits, 8 - dst_ofs);
1289 *dst |= ((1 << chunk) - 1) << dst_ofs;
1299 while (n_bits >= 8) {
1305 *dst |= (1 << n_bits) - 1;
1309 /* Scans the 'n_bits' bits starting from bit 'dst_ofs' in 'dst' for 1-bits.
1310 * Returns false if any 1-bits are found, otherwise true. 'dst' is 'dst_len'
1313 * If you consider all of 'dst' to be a single unsigned integer in network byte
1314 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1315 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1316 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1319 * Required invariant:
1320 * dst_ofs + n_bits <= dst_len * 8
1323 bitwise_is_all_zeros(const void *p_, unsigned int len, unsigned int ofs,
1324 unsigned int n_bits)
1326 const uint8_t *p = p_;
1332 p += len - (ofs / 8 + 1);
1336 unsigned int chunk = MIN(n_bits, 8 - ofs);
1338 if (*p & (((1 << chunk) - 1) << ofs)) {
1350 while (n_bits >= 8) {
1358 if (n_bits && *p & ((1 << n_bits) - 1)) {
1365 /* Scans the bits in 'p' that have bit offsets 'start' (inclusive) through
1366 * 'end' (exclusive) for the first bit with value 'target'. If one is found,
1367 * returns its offset, otherwise 'end'. 'p' is 'len' bytes long.
1369 * If you consider all of 'p' to be a single unsigned integer in network byte
1370 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1371 * with value 1 in p[len - 1], bit 1 is the bit with value 2, bit 2 is the bit
1372 * with value 4, ..., bit 8 is the bit with value 1 in p[len - 2], and so on.
1374 * Required invariant:
1378 bitwise_scan(const void *p, unsigned int len, bool target, unsigned int start,
1383 for (ofs = start; ofs < end; ofs++) {
1384 if (bitwise_get_bit(p, len, ofs) == target) {
1391 /* Scans the bits in 'p' that have bit offsets 'start' (inclusive) through
1392 * 'end' (exclusive) for the first bit with value 'target', in reverse order.
1393 * If one is found, returns its offset, otherwise 'end'. 'p' is 'len' bytes
1396 * If you consider all of 'p' to be a single unsigned integer in network byte
1397 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1398 * with value 1 in p[len - 1], bit 1 is the bit with value 2, bit 2 is the bit
1399 * with value 4, ..., bit 8 is the bit with value 1 in p[len - 2], and so on.
1401 * To scan an entire bit array in reverse order, specify start == len * 8 - 1
1402 * and end == -1, in which case the return value is nonnegative if successful
1403 * and -1 if no 'target' match is found.
1405 * Required invariant:
1409 bitwise_rscan(const void *p, unsigned int len, bool target, int start, int end)
1411 const uint8_t *s = p;
1412 int start_byte = len - (start / 8 + 1);
1413 int end_byte = len - (end / 8 + 1);
1418 /* Find the target in the start_byte from starting offset */
1419 ofs_byte = start_byte;
1420 the_byte = s[ofs_byte];
1421 for (ofs = start % 8; ofs >= 0; ofs--) {
1422 if (((the_byte & (1u << ofs)) != 0) == target) {
1427 /* Target not found in start byte, continue searching byte by byte */
1428 for (ofs_byte = start_byte + 1; ofs_byte <= end_byte; ofs_byte++) {
1429 if ((target && s[ofs_byte])
1430 || (!target && (s[ofs_byte] != 0xff))) {
1434 if (ofs_byte > end_byte) {
1437 the_byte = s[ofs_byte];
1438 /* Target is in the_byte, find it bit by bit */
1439 for (ofs = 7; ofs >= 0; ofs--) {
1440 if (((the_byte & (1u << ofs)) != 0) == target) {
1445 int ret = (len - ofs_byte) * 8 - (8 - ofs);
1452 /* Copies the 'n_bits' low-order bits of 'value' into the 'n_bits' bits
1453 * starting at bit 'dst_ofs' in 'dst', which is 'dst_len' bytes long.
1455 * If you consider all of 'dst' to be a single unsigned integer in network byte
1456 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1457 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1458 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1461 * Required invariants:
1462 * dst_ofs + n_bits <= dst_len * 8
1466 bitwise_put(uint64_t value,
1467 void *dst, unsigned int dst_len, unsigned int dst_ofs,
1468 unsigned int n_bits)
1470 ovs_be64 n_value = htonll(value);
1471 bitwise_copy(&n_value, sizeof n_value, 0,
1472 dst, dst_len, dst_ofs,
1476 /* Returns the value of the 'n_bits' bits starting at bit 'src_ofs' in 'src',
1477 * which is 'src_len' bytes long.
1479 * If you consider all of 'src' to be a single unsigned integer in network byte
1480 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1481 * with value 1 in src[src_len - 1], bit 1 is the bit with value 2, bit 2 is
1482 * the bit with value 4, ..., bit 8 is the bit with value 1 in src[src_len -
1485 * Required invariants:
1486 * src_ofs + n_bits <= src_len * 8
1490 bitwise_get(const void *src, unsigned int src_len,
1491 unsigned int src_ofs, unsigned int n_bits)
1493 ovs_be64 value = htonll(0);
1495 bitwise_copy(src, src_len, src_ofs,
1496 &value, sizeof value, 0,
1498 return ntohll(value);
1501 /* Returns the value of the bit with offset 'ofs' in 'src', which is 'len'
1504 * If you consider all of 'src' to be a single unsigned integer in network byte
1505 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1506 * with value 1 in src[len - 1], bit 1 is the bit with value 2, bit 2 is the
1507 * bit with value 4, ..., bit 8 is the bit with value 1 in src[len - 2], and so
1510 * Required invariants:
1514 bitwise_get_bit(const void *src_, unsigned int len, unsigned int ofs)
1516 const uint8_t *src = src_;
1518 return (src[len - (ofs / 8 + 1)] & (1u << (ofs % 8))) != 0;
1521 /* Sets the bit with offset 'ofs' in 'dst', which is 'len' bytes long, to 0.
1523 * If you consider all of 'dst' to be a single unsigned integer in network byte
1524 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1525 * with value 1 in dst[len - 1], bit 1 is the bit with value 2, bit 2 is the
1526 * bit with value 4, ..., bit 8 is the bit with value 1 in dst[len - 2], and so
1529 * Required invariants:
1533 bitwise_put0(void *dst_, unsigned int len, unsigned int ofs)
1535 uint8_t *dst = dst_;
1537 dst[len - (ofs / 8 + 1)] &= ~(1u << (ofs % 8));
1540 /* Sets the bit with offset 'ofs' in 'dst', which is 'len' bytes long, to 1.
1542 * If you consider all of 'dst' to be a single unsigned integer in network byte
1543 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1544 * with value 1 in dst[len - 1], bit 1 is the bit with value 2, bit 2 is the
1545 * bit with value 4, ..., bit 8 is the bit with value 1 in dst[len - 2], and so
1548 * Required invariants:
1552 bitwise_put1(void *dst_, unsigned int len, unsigned int ofs)
1554 uint8_t *dst = dst_;
1556 dst[len - (ofs / 8 + 1)] |= 1u << (ofs % 8);
1559 /* Sets the bit with offset 'ofs' in 'dst', which is 'len' bytes long, to 'b'.
1561 * If you consider all of 'dst' to be a single unsigned integer in network byte
1562 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1563 * with value 1 in dst[len - 1], bit 1 is the bit with value 2, bit 2 is the
1564 * bit with value 4, ..., bit 8 is the bit with value 1 in dst[len - 2], and so
1567 * Required invariants:
1571 bitwise_put_bit(void *dst, unsigned int len, unsigned int ofs, bool b)
1574 bitwise_put1(dst, len, ofs);
1576 bitwise_put0(dst, len, ofs);
1580 /* Flips the bit with offset 'ofs' in 'dst', which is 'len' bytes long.
1582 * If you consider all of 'dst' to be a single unsigned integer in network byte
1583 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1584 * with value 1 in dst[len - 1], bit 1 is the bit with value 2, bit 2 is the
1585 * bit with value 4, ..., bit 8 is the bit with value 1 in dst[len - 2], and so
1588 * Required invariants:
1592 bitwise_toggle_bit(void *dst_, unsigned int len, unsigned int ofs)
1594 uint8_t *dst = dst_;
1596 dst[len - (ofs / 8 + 1)] ^= 1u << (ofs % 8);
1617 skip_spaces(const char *s)
1619 while (isspace((unsigned char) *s)) {
1626 scan_int(const char *s, const struct scan_spec *spec, int base, va_list *args)
1628 const char *start = s;
1633 negative = *s == '-';
1634 s += *s == '-' || *s == '+';
1636 if ((!base || base == 16) && *s == '0' && (s[1] == 'x' || s[1] == 'X')) {
1640 base = *s == '0' ? 8 : 10;
1643 if (s - start >= spec->width) {
1649 while (s - start < spec->width) {
1650 int digit = hexit_value(*s);
1652 if (digit < 0 || digit >= base) {
1655 value = value * base + digit;
1667 switch (spec->type) {
1671 *va_arg(*args, char *) = value;
1674 *va_arg(*args, short int *) = value;
1677 *va_arg(*args, int *) = value;
1680 *va_arg(*args, long int *) = value;
1683 *va_arg(*args, long long int *) = value;
1686 *va_arg(*args, intmax_t *) = value;
1688 case SCAN_PTRDIFF_T:
1689 *va_arg(*args, ptrdiff_t *) = value;
1692 *va_arg(*args, size_t *) = value;
1699 skip_digits(const char *s)
1701 while (*s >= '0' && *s <= '9') {
1708 scan_float(const char *s, const struct scan_spec *spec, va_list *args)
1710 const char *start = s;
1716 s += *s == '+' || *s == '-';
1719 s = skip_digits(s + 1);
1721 if (*s == 'e' || *s == 'E') {
1723 s += *s == '+' || *s == '-';
1727 if (s - start > spec->width) {
1728 s = start + spec->width;
1731 copy = xmemdup0(start, s - start);
1732 value = strtold(copy, &tail);
1739 switch (spec->type) {
1743 *va_arg(*args, float *) = value;
1746 *va_arg(*args, double *) = value;
1749 *va_arg(*args, long double *) = value;
1755 case SCAN_PTRDIFF_T:
1763 scan_output_string(const struct scan_spec *spec,
1764 const char *s, size_t n,
1767 if (spec->type != SCAN_DISCARD) {
1768 char *out = va_arg(*args, char *);
1775 scan_string(const char *s, const struct scan_spec *spec, va_list *args)
1779 for (n = 0; n < spec->width; n++) {
1780 if (!s[n] || isspace((unsigned char) s[n])) {
1788 scan_output_string(spec, s, n, args);
1793 parse_scanset(const char *p_, unsigned long *set, bool *complemented)
1795 const uint8_t *p = (const uint8_t *) p_;
1797 *complemented = *p == '^';
1801 bitmap_set1(set, ']');
1805 while (*p && *p != ']') {
1806 if (p[1] == '-' && p[2] != ']' && p[2] > *p) {
1807 bitmap_set_multiple(set, *p, p[2] - *p + 1, true);
1810 bitmap_set1(set, *p++);
1816 return (const char *) p;
1820 scan_set(const char *s, const struct scan_spec *spec, const char **pp,
1823 unsigned long set[BITMAP_N_LONGS(UCHAR_MAX + 1)];
1827 /* Parse the scan set. */
1828 memset(set, 0, sizeof set);
1829 *pp = parse_scanset(*pp, set, &complemented);
1831 /* Parse the data. */
1834 && bitmap_is_set(set, (unsigned char) s[n]) == !complemented
1835 && n < spec->width) {
1841 scan_output_string(spec, s, n, args);
1846 scan_chars(const char *s, const struct scan_spec *spec, va_list *args)
1848 unsigned int n = spec->width == UINT_MAX ? 1 : spec->width;
1850 if (strlen(s) < n) {
1853 if (spec->type != SCAN_DISCARD) {
1854 memcpy(va_arg(*args, char *), s, n);
1860 ovs_scan__(const char *s, int *n, const char *format, va_list *args)
1862 const char *const start = s;
1867 while (*p != '\0') {
1868 struct scan_spec spec;
1869 unsigned char c = *p++;
1875 } else if (c != '%') {
1881 } else if (*p == '%') {
1889 /* Parse '*' flag. */
1890 discard = *p == '*';
1893 /* Parse field width. */
1895 while (*p >= '0' && *p <= '9') {
1896 spec.width = spec.width * 10 + (*p++ - '0');
1898 if (spec.width == 0) {
1899 spec.width = UINT_MAX;
1902 /* Parse type modifier. */
1906 spec.type = SCAN_CHAR;
1909 spec.type = SCAN_SHORT;
1915 spec.type = SCAN_INTMAX_T;
1921 spec.type = SCAN_LLONG;
1924 spec.type = SCAN_LONG;
1931 spec.type = SCAN_LLONG;
1936 spec.type = SCAN_PTRDIFF_T;
1941 spec.type = SCAN_SIZE_T;
1946 spec.type = SCAN_INT;
1951 spec.type = SCAN_DISCARD;
1955 if (c != 'c' && c != 'n' && c != '[') {
1960 s = scan_int(s, &spec, 10, args);
1964 s = scan_int(s, &spec, 0, args);
1968 s = scan_int(s, &spec, 8, args);
1972 s = scan_int(s, &spec, 10, args);
1977 s = scan_int(s, &spec, 16, args);
1985 s = scan_float(s, &spec, args);
1989 s = scan_string(s, &spec, args);
1993 s = scan_set(s, &spec, &p, args);
1997 s = scan_chars(s, &spec, args);
2001 if (spec.type != SCAN_DISCARD) {
2002 *va_arg(*args, int *) = s - start;
2020 /* This is an implementation of the standard sscanf() function, with the
2021 * following exceptions:
2023 * - It returns true if the entire format was successfully scanned and
2024 * converted, false if any conversion failed.
2026 * - The standard doesn't define sscanf() behavior when an out-of-range value
2027 * is scanned, e.g. if a "%"PRIi8 conversion scans "-1" or "0x1ff". Some
2028 * implementations consider this an error and stop scanning. This
2029 * implementation never considers an out-of-range value an error; instead,
2030 * it stores the least-significant bits of the converted value in the
2031 * destination, e.g. the value 255 for both examples earlier.
2033 * - Only single-byte characters are supported, that is, the 'l' modifier
2034 * on %s, %[, and %c is not supported. The GNU extension 'a' modifier is
2035 * also not supported.
2037 * - %p is not supported.
2040 ovs_scan(const char *s, const char *format, ...)
2045 va_start(args, format);
2046 res = ovs_scan__(s, NULL, format, &args);
2052 * This function is similar to ovs_scan(), with an extra parameter `n` added to
2053 * return the number of scanned characters.
2056 ovs_scan_len(const char *s, int *n, const char *format, ...)
2062 va_start(args, format);
2063 success = ovs_scan__(s + *n, &n1, format, &args);
2072 xsleep(unsigned int seconds)
2074 ovsrcu_quiesce_start();
2076 Sleep(seconds * 1000);
2080 ovsrcu_quiesce_end();
2083 /* Determine whether standard output is a tty or not. This is useful to decide
2084 * whether to use color output or not when --color option for utilities is set
2088 is_stdout_a_tty(void)
2090 char const *t = getenv("TERM");
2091 return (isatty(STDOUT_FILENO) && t && strcmp(t, "dumb") != 0);
2097 ovs_format_message(int error)
2099 enum { BUFSIZE = sizeof strerror_buffer_get()->s };
2100 char *buffer = strerror_buffer_get()->s;
2103 /* See ovs_strerror */
2107 FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
2108 NULL, error, 0, buffer, BUFSIZE, NULL);
2112 /* Returns a null-terminated string that explains the last error.
2113 * Use this function to get the error string for WINAPI calls. */
2115 ovs_lasterror_to_string(void)
2117 return ovs_format_message(GetLastError());
2121 ftruncate(int fd, off_t length)
2125 error = _chsize_s(fd, length);
2132 OVS_CONSTRUCTOR(winsock_start) {
2136 error = WSAStartup(MAKEWORD(2, 2), &wsaData);
2138 VLOG_FATAL("WSAStartup failed: %s", sock_strerror(sock_errno()));