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"
33 #include "ovs-thread.h"
35 #ifdef HAVE_PTHREAD_SET_NAME_NP
36 #include <pthread_np.h>
39 VLOG_DEFINE_THIS_MODULE(util);
41 COVERAGE_DEFINE(util_xalloc);
43 /* argv[0] without directory names. */
44 const char *program_name;
46 /* Name for the currently running thread or process, for log messages, process
47 * listings, and debuggers. */
48 DEFINE_PER_THREAD_MALLOCED_DATA(char *, subprogram_name);
50 /* --version option output. */
51 static char *program_version;
53 /* Buffer used by ovs_strerror() and ovs_format_message(). */
54 DEFINE_STATIC_PER_THREAD_DATA(struct { char s[128]; },
58 static char *xreadlink(const char *filename);
61 ovs_assert_failure(const char *where, const char *function,
62 const char *condition)
64 /* Prevent an infinite loop (or stack overflow) in case VLOG_ABORT happens
65 * to trigger an assertion failure of its own. */
66 static int reentry = 0;
70 VLOG_ABORT("%s: assertion %s failed in %s()",
71 where, condition, function);
75 fprintf(stderr, "%s: assertion %s failed in %s()",
76 where, condition, function);
87 ovs_abort(0, "virtual memory exhausted");
91 xcalloc(size_t count, size_t size)
93 void *p = count && size ? calloc(count, size) : malloc(1);
94 COVERAGE_INC(util_xalloc);
104 return xcalloc(1, size);
110 void *p = malloc(size ? size : 1);
111 COVERAGE_INC(util_xalloc);
119 xrealloc(void *p, size_t size)
121 p = realloc(p, size ? size : 1);
122 COVERAGE_INC(util_xalloc);
130 xmemdup(const void *p_, size_t size)
132 void *p = xmalloc(size);
138 xmemdup0(const char *p_, size_t length)
140 char *p = xmalloc(length + 1);
141 memcpy(p, p_, length);
147 xstrdup(const char *s)
149 return xmemdup0(s, strlen(s));
153 xvasprintf(const char *format, va_list args)
159 va_copy(args2, args);
160 needed = vsnprintf(NULL, 0, format, args);
162 s = xmalloc(needed + 1);
164 vsnprintf(s, needed + 1, format, args2);
171 x2nrealloc(void *p, size_t *n, size_t s)
173 *n = *n == 0 ? 1 : 2 * *n;
174 return xrealloc(p, *n * s);
177 /* The desired minimum alignment for an allocated block of memory. */
178 #define MEM_ALIGN MAX(sizeof(void *), 8)
179 BUILD_ASSERT_DECL(IS_POW2(MEM_ALIGN));
180 BUILD_ASSERT_DECL(CACHE_LINE_SIZE >= MEM_ALIGN);
182 /* Allocates and returns 'size' bytes of memory in dedicated cache lines. That
183 * is, the memory block returned will not share a cache line with other data,
184 * avoiding "false sharing". (The memory returned will not be at the start of
185 * a cache line, though, so don't assume such alignment.)
187 * Use free_cacheline() to free the returned memory block. */
189 xmalloc_cacheline(size_t size)
194 /* Allocate room for:
196 * - Up to CACHE_LINE_SIZE - 1 bytes before the payload, so that the
197 * start of the payload doesn't potentially share a cache line.
199 * - A payload consisting of a void *, followed by padding out to
200 * MEM_ALIGN bytes, followed by 'size' bytes of user data.
202 * - Space following the payload up to the end of the cache line, so
203 * that the end of the payload doesn't potentially share a cache line
204 * with some following block. */
205 base = xmalloc((CACHE_LINE_SIZE - 1)
206 + ROUND_UP(MEM_ALIGN + size, CACHE_LINE_SIZE));
208 /* Locate the payload and store a pointer to the base at the beginning. */
209 payload = (void **) ROUND_UP((uintptr_t) base, CACHE_LINE_SIZE);
212 return (char *) payload + MEM_ALIGN;
215 /* Like xmalloc_cacheline() but clears the allocated memory to all zero
218 xzalloc_cacheline(size_t size)
220 void *p = xmalloc_cacheline(size);
225 /* Frees a memory block allocated with xmalloc_cacheline() or
226 * xzalloc_cacheline(). */
228 free_cacheline(void *p)
231 free(*(void **) ((uintptr_t) p - MEM_ALIGN));
236 xasprintf(const char *format, ...)
241 va_start(args, format);
242 s = xvasprintf(format, args);
248 /* Similar to strlcpy() from OpenBSD, but it never reads more than 'size - 1'
249 * bytes from 'src' and doesn't return anything. */
251 ovs_strlcpy(char *dst, const char *src, size_t size)
254 size_t len = strnlen(src, size - 1);
255 memcpy(dst, src, len);
260 /* Copies 'src' to 'dst'. Reads no more than 'size - 1' bytes from 'src'.
261 * Always null-terminates 'dst' (if 'size' is nonzero), and writes a zero byte
262 * to every otherwise unused byte in 'dst'.
264 * Except for performance, the following call:
265 * ovs_strzcpy(dst, src, size);
266 * is equivalent to these two calls:
267 * memset(dst, '\0', size);
268 * ovs_strlcpy(dst, src, size);
270 * (Thus, ovs_strzcpy() is similar to strncpy() without some of the pitfalls.)
273 ovs_strzcpy(char *dst, const char *src, size_t size)
276 size_t len = strnlen(src, size - 1);
277 memcpy(dst, src, len);
278 memset(dst + len, '\0', size - len);
282 /* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
283 * nonzero, then it is formatted with ovs_retval_to_string() and appended to
284 * the message inside parentheses. Then, terminates with abort().
286 * This function is preferred to ovs_fatal() in a situation where it would make
287 * sense for a monitoring process to restart the daemon.
289 * 'format' should not end with a new-line, because this function will add one
292 ovs_abort(int err_no, const char *format, ...)
296 va_start(args, format);
297 ovs_abort_valist(err_no, format, args);
300 /* Same as ovs_abort() except that the arguments are supplied as a va_list. */
302 ovs_abort_valist(int err_no, const char *format, va_list args)
304 ovs_error_valist(err_no, format, args);
308 /* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
309 * nonzero, then it is formatted with ovs_retval_to_string() and appended to
310 * the message inside parentheses. Then, terminates with EXIT_FAILURE.
312 * 'format' should not end with a new-line, because this function will add one
315 ovs_fatal(int err_no, const char *format, ...)
319 va_start(args, format);
320 ovs_fatal_valist(err_no, format, args);
323 /* Same as ovs_fatal() except that the arguments are supplied as a va_list. */
325 ovs_fatal_valist(int err_no, const char *format, va_list args)
327 ovs_error_valist(err_no, format, args);
331 /* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
332 * nonzero, then it is formatted with ovs_retval_to_string() and appended to
333 * the message inside parentheses.
335 * 'format' should not end with a new-line, because this function will add one
338 ovs_error(int err_no, const char *format, ...)
342 va_start(args, format);
343 ovs_error_valist(err_no, format, args);
347 /* Same as ovs_error() except that the arguments are supplied as a va_list. */
349 ovs_error_valist(int err_no, const char *format, va_list args)
351 const char *subprogram_name = get_subprogram_name();
352 int save_errno = errno;
354 if (subprogram_name[0]) {
355 fprintf(stderr, "%s(%s): ", program_name, subprogram_name);
357 fprintf(stderr, "%s: ", program_name);
360 vfprintf(stderr, format, args);
362 fprintf(stderr, " (%s)", ovs_retval_to_string(err_no));
369 /* Many OVS functions return an int which is one of:
372 * - EOF: end of file (not necessarily an error; depends on the function called)
374 * Returns the appropriate human-readable string. The caller must copy the
375 * string if it wants to hold onto it, as the storage may be overwritten on
376 * subsequent function calls.
379 ovs_retval_to_string(int retval)
382 : retval == EOF ? "End of file"
383 : ovs_strerror(retval));
386 /* This function returns the string describing the error number in 'error'
387 * for POSIX platforms. For Windows, this function can be used for C library
388 * calls. For socket calls that are also used in Windows, use sock_strerror()
389 * instead. For WINAPI calls, look at ovs_lasterror_to_string(). */
391 ovs_strerror(int error)
393 enum { BUFSIZE = sizeof strerror_buffer_get()->s };
399 buffer = strerror_buffer_get()->s;
401 #if STRERROR_R_CHAR_P
402 /* GNU style strerror_r() might return an immutable static string, or it
403 * might write and return 'buffer', but in either case we can pass the
404 * returned string directly to the caller. */
405 s = strerror_r(error, buffer, BUFSIZE);
406 #else /* strerror_r() returns an int. */
408 if (strerror_r(error, buffer, BUFSIZE)) {
409 /* strerror_r() is only allowed to fail on ERANGE (because the buffer
410 * is too short). We don't check the actual failure reason because
411 * POSIX requires strerror_r() to return the error but old glibc
412 * (before 2.13) returns -1 and sets errno. */
413 snprintf(buffer, BUFSIZE, "Unknown error %d", error);
422 /* Sets global "program_name" and "program_version" variables. Should
423 * be called at the beginning of main() with "argv[0]" as the argument
426 * 'version' should contain the version of the caller's program. If 'version'
427 * is the same as the VERSION #define, the caller is assumed to be part of Open
428 * vSwitch. Otherwise, it is assumed to be an external program linking against
429 * the Open vSwitch libraries.
431 * The 'date' and 'time' arguments should likely be called with
432 * "__DATE__" and "__TIME__" to use the time the binary was built.
433 * Alternatively, the "set_program_name" macro may be called to do this
437 set_program_name__(const char *argv0, const char *version, const char *date,
442 size_t max_len = strlen(argv0) + 1;
447 basename = xmalloc(max_len);
448 _splitpath_s(argv0, NULL, 0, NULL, 0, basename, max_len, NULL, 0);
449 assert_single_threaded();
450 program_name = basename;
452 const char *slash = strrchr(argv0, '/');
453 assert_single_threaded();
454 program_name = slash ? slash + 1 : argv0;
457 free(program_version);
459 if (!strcmp(version, VERSION)) {
460 program_version = xasprintf("%s (Open vSwitch) "VERSION"\n"
462 program_name, date, time);
464 program_version = xasprintf("%s %s\n"
465 "Open vSwitch Library "VERSION"\n"
467 program_name, version, date, time);
471 /* Returns the name of the currently running thread or process. */
473 get_subprogram_name(void)
475 const char *name = subprogram_name_get();
476 return name ? name : "";
479 /* Sets the formatted value of 'format' as the name of the currently running
480 * thread or process. (This appears in log messages and may also be visible in
481 * system process listings and debuggers.) */
483 set_subprogram_name(const char *format, ...)
490 va_start(args, format);
491 pname = xvasprintf(format, args);
494 pname = xstrdup(program_name);
497 free(subprogram_name_set(pname));
499 #if HAVE_GLIBC_PTHREAD_SETNAME_NP
500 pthread_setname_np(pthread_self(), pname);
501 #elif HAVE_NETBSD_PTHREAD_SETNAME_NP
502 pthread_setname_np(pthread_self(), "%s", pname);
503 #elif HAVE_PTHREAD_SET_NAME_NP
504 pthread_set_name_np(pthread_self(), pname);
508 /* Returns a pointer to a string describing the program version. The
509 * caller must not modify or free the returned string.
512 get_program_version(void)
514 return program_version;
517 /* Print the version information for the program. */
519 ovs_print_version(uint8_t min_ofp, uint8_t max_ofp)
521 printf("%s", program_version);
522 if (min_ofp || max_ofp) {
523 printf("OpenFlow versions %#x:%#x\n", min_ofp, max_ofp);
527 /* Writes the 'size' bytes in 'buf' to 'stream' as hex bytes arranged 16 per
528 * line. Numeric offsets are also included, starting at 'ofs' for the first
529 * byte in 'buf'. If 'ascii' is true then the corresponding ASCII characters
530 * are also rendered alongside. */
532 ovs_hex_dump(FILE *stream, const void *buf_, size_t size,
533 uintptr_t ofs, bool ascii)
535 const uint8_t *buf = buf_;
536 const size_t per_line = 16; /* Maximum bytes per line. */
540 size_t start, end, n;
543 /* Number of bytes on this line. */
544 start = ofs % per_line;
546 if (end - start > size)
551 fprintf(stream, "%08"PRIxMAX" ", (uintmax_t) ROUND_DOWN(ofs, per_line));
552 for (i = 0; i < start; i++)
553 fprintf(stream, " ");
555 fprintf(stream, "%02x%c",
556 buf[i - start], i == per_line / 2 - 1? '-' : ' ');
559 for (; i < per_line; i++)
560 fprintf(stream, " ");
561 fprintf(stream, "|");
562 for (i = 0; i < start; i++)
563 fprintf(stream, " ");
564 for (; i < end; i++) {
565 int c = buf[i - start];
566 putc(c >= 32 && c < 127 ? c : '.', stream);
568 for (; i < per_line; i++)
569 fprintf(stream, " ");
570 fprintf(stream, "|");
572 fprintf(stream, "\n");
581 str_to_int(const char *s, int base, int *i)
584 bool ok = str_to_llong(s, base, &ll);
590 str_to_long(const char *s, int base, long *li)
593 bool ok = str_to_llong(s, base, &ll);
599 str_to_llong(const char *s, int base, long long *x)
601 int save_errno = errno;
604 *x = strtoll(s, &tail, base);
605 if (errno == EINVAL || errno == ERANGE || tail == s || *tail != '\0') {
615 /* Converts floating-point string 's' into a double. If successful, stores
616 * the double in '*d' and returns true; on failure, stores 0 in '*d' and
619 * Underflow (e.g. "1e-9999") is not considered an error, but overflow
620 * (e.g. "1e9999)" is. */
622 str_to_double(const char *s, double *d)
624 int save_errno = errno;
627 *d = strtod(s, &tail);
628 if (errno == EINVAL || (errno == ERANGE && *d != 0)
629 || tail == s || *tail != '\0') {
639 /* Returns the value of 'c' as a hexadecimal digit. */
644 case '0': case '1': case '2': case '3': case '4':
645 case '5': case '6': case '7': case '8': case '9':
671 /* Returns the integer value of the 'n' hexadecimal digits starting at 's', or
672 * UINT_MAX if one of those "digits" is not really a hex digit. If 'ok' is
673 * nonnull, '*ok' is set to true if the conversion succeeds or to false if a
674 * non-hex digit is detected. */
676 hexits_value(const char *s, size_t n, bool *ok)
682 for (i = 0; i < n; i++) {
683 int hexit = hexit_value(s[i]);
690 value = (value << 4) + hexit;
698 /* Returns the current working directory as a malloc()'d string, or a null
699 * pointer if the current working directory cannot be determined. */
706 /* Get maximum path length or at least a reasonable estimate. */
708 path_max = pathconf(".", _PC_PATH_MAX);
712 size = (path_max < 0 ? 1024
713 : path_max > 10240 ? 10240
716 /* Get current working directory. */
718 char *buf = xmalloc(size);
719 if (getcwd(buf, size)) {
720 return xrealloc(buf, strlen(buf) + 1);
724 if (error != ERANGE) {
725 VLOG_WARN("getcwd failed (%s)", ovs_strerror(error));
734 all_slashes_name(const char *s)
736 return xstrdup(s[0] == '/' && s[1] == '/' && s[2] != '/' ? "//"
741 /* Returns the directory name portion of 'file_name' as a malloc()'d string,
742 * similar to the POSIX dirname() function but thread-safe. */
744 dir_name(const char *file_name)
746 size_t len = strlen(file_name);
747 while (len > 0 && file_name[len - 1] == '/') {
750 while (len > 0 && file_name[len - 1] != '/') {
753 while (len > 0 && file_name[len - 1] == '/') {
756 return len ? xmemdup0(file_name, len) : all_slashes_name(file_name);
759 /* Returns the file name portion of 'file_name' as a malloc()'d string,
760 * similar to the POSIX basename() function but thread-safe. */
762 base_name(const char *file_name)
766 end = strlen(file_name);
767 while (end > 0 && file_name[end - 1] == '/') {
772 return all_slashes_name(file_name);
776 while (start > 0 && file_name[start - 1] != '/') {
780 return xmemdup0(file_name + start, end - start);
783 /* If 'file_name' starts with '/', returns a copy of 'file_name'. Otherwise,
784 * returns an absolute path to 'file_name' considering it relative to 'dir',
785 * which itself must be absolute. 'dir' may be null or the empty string, in
786 * which case the current working directory is used.
788 * Returns a null pointer if 'dir' is null and getcwd() fails. */
790 abs_file_name(const char *dir, const char *file_name)
792 if (file_name[0] == '/') {
793 return xstrdup(file_name);
794 } else if (dir && dir[0]) {
795 char *separator = dir[strlen(dir) - 1] == '/' ? "" : "/";
796 return xasprintf("%s%s%s", dir, separator, file_name);
798 char *cwd = get_cwd();
800 char *abs_name = xasprintf("%s/%s", cwd, file_name);
809 /* Like readlink(), but returns the link name as a null-terminated string in
810 * allocated memory that the caller must eventually free (with free()).
811 * Returns NULL on error, in which case errno is set appropriately. */
813 xreadlink(const char *filename)
817 for (size = 64; ; size *= 2) {
818 char *buf = xmalloc(size);
819 ssize_t retval = readlink(filename, buf, size);
822 if (retval >= 0 && retval < size) {
835 /* Returns a version of 'filename' with symlinks in the final component
836 * dereferenced. This differs from realpath() in that:
838 * - 'filename' need not exist.
840 * - If 'filename' does exist as a symlink, its referent need not exist.
842 * - Only symlinks in the final component of 'filename' are dereferenced.
844 * For Windows platform, this function returns a string that has the same
845 * value as the passed string.
847 * The caller must eventually free the returned string (with free()). */
849 follow_symlinks(const char *filename)
856 fn = xstrdup(filename);
857 for (i = 0; i < 10; i++) {
861 if (lstat(fn, &s) != 0 || !S_ISLNK(s.st_mode)) {
865 linkname = xreadlink(fn);
867 VLOG_WARN("%s: readlink failed (%s)",
868 filename, ovs_strerror(errno));
872 if (linkname[0] == '/') {
873 /* Target of symlink is absolute so use it raw. */
876 /* Target of symlink is relative so add to 'fn''s directory. */
877 char *dir = dir_name(fn);
879 if (!strcmp(dir, ".")) {
882 char *separator = dir[strlen(dir) - 1] == '/' ? "" : "/";
883 next_fn = xasprintf("%s%s%s", dir, separator, linkname);
894 VLOG_WARN("%s: too many levels of symlinks", filename);
897 return xstrdup(filename);
900 /* Pass a value to this function if it is marked with
901 * __attribute__((warn_unused_result)) and you genuinely want to ignore
902 * its return value. (Note that every scalar type can be implicitly
903 * converted to bool.) */
904 void ignore(bool x OVS_UNUSED) { }
906 /* Returns an appropriate delimiter for inserting just before the 0-based item
907 * 'index' in a list that has 'total' items in it. */
909 english_list_delimiter(size_t index, size_t total)
911 return (index == 0 ? ""
912 : index < total - 1 ? ", "
913 : total > 2 ? ", and "
917 /* Returns the number of trailing 0-bits in 'n'. Undefined if 'n' == 0. */
919 /* Defined inline in util.h. */
921 /* Returns the number of trailing 0-bits in 'n'. Undefined if 'n' == 0. */
928 #define CTZ_STEP(X) \
945 /* Returns the number of leading 0-bits in 'n'. Undefined if 'n' == 0. */
947 raw_clz64(uint64_t n)
952 #define CLZ_STEP(X) \
970 #if NEED_COUNT_1BITS_8
972 ((((X) & (1 << 0)) != 0) + \
973 (((X) & (1 << 1)) != 0) + \
974 (((X) & (1 << 2)) != 0) + \
975 (((X) & (1 << 3)) != 0) + \
976 (((X) & (1 << 4)) != 0) + \
977 (((X) & (1 << 5)) != 0) + \
978 (((X) & (1 << 6)) != 0) + \
979 (((X) & (1 << 7)) != 0))
980 #define INIT2(X) INIT1(X), INIT1((X) + 1)
981 #define INIT4(X) INIT2(X), INIT2((X) + 2)
982 #define INIT8(X) INIT4(X), INIT4((X) + 4)
983 #define INIT16(X) INIT8(X), INIT8((X) + 8)
984 #define INIT32(X) INIT16(X), INIT16((X) + 16)
985 #define INIT64(X) INIT32(X), INIT32((X) + 32)
987 const uint8_t count_1bits_8[256] = {
988 INIT64(0), INIT64(64), INIT64(128), INIT64(192)
992 /* Returns true if the 'n' bytes starting at 'p' are zeros. */
994 is_all_zeros(const uint8_t *p, size_t n)
998 for (i = 0; i < n; i++) {
1006 /* Returns true if the 'n' bytes starting at 'p' are 0xff. */
1008 is_all_ones(const uint8_t *p, size_t n)
1012 for (i = 0; i < n; i++) {
1020 /* Copies 'n_bits' bits starting from bit 'src_ofs' in 'src' to the 'n_bits'
1021 * starting from bit 'dst_ofs' in 'dst'. 'src' is 'src_len' bytes long and
1022 * 'dst' is 'dst_len' bytes long.
1024 * If you consider all of 'src' to be a single unsigned integer in network byte
1025 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1026 * with value 1 in src[src_len - 1], bit 1 is the bit with value 2, bit 2 is
1027 * the bit with value 4, ..., bit 8 is the bit with value 1 in src[src_len -
1028 * 2], and so on. Similarly for 'dst'.
1030 * Required invariants:
1031 * src_ofs + n_bits <= src_len * 8
1032 * dst_ofs + n_bits <= dst_len * 8
1033 * 'src' and 'dst' must not overlap.
1036 bitwise_copy(const void *src_, unsigned int src_len, unsigned int src_ofs,
1037 void *dst_, unsigned int dst_len, unsigned int dst_ofs,
1038 unsigned int n_bits)
1040 const uint8_t *src = src_;
1041 uint8_t *dst = dst_;
1043 src += src_len - (src_ofs / 8 + 1);
1046 dst += dst_len - (dst_ofs / 8 + 1);
1049 if (src_ofs == 0 && dst_ofs == 0) {
1050 unsigned int n_bytes = n_bits / 8;
1054 memcpy(dst, src, n_bytes);
1061 uint8_t mask = (1 << n_bits) - 1;
1062 *dst = (*dst & ~mask) | (*src & mask);
1065 while (n_bits > 0) {
1066 unsigned int max_copy = 8 - MAX(src_ofs, dst_ofs);
1067 unsigned int chunk = MIN(n_bits, max_copy);
1068 uint8_t mask = ((1 << chunk) - 1) << dst_ofs;
1071 *dst |= ((*src >> src_ofs) << dst_ofs) & mask;
1088 /* Zeros the 'n_bits' bits starting from bit 'dst_ofs' in 'dst'. 'dst' is
1089 * 'dst_len' bytes long.
1091 * If you consider all of 'dst' to be a single unsigned integer in network byte
1092 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1093 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1094 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1097 * Required invariant:
1098 * dst_ofs + n_bits <= dst_len * 8
1101 bitwise_zero(void *dst_, unsigned int dst_len, unsigned dst_ofs,
1102 unsigned int n_bits)
1104 uint8_t *dst = dst_;
1110 dst += dst_len - (dst_ofs / 8 + 1);
1114 unsigned int chunk = MIN(n_bits, 8 - dst_ofs);
1116 *dst &= ~(((1 << chunk) - 1) << dst_ofs);
1126 while (n_bits >= 8) {
1132 *dst &= ~((1 << n_bits) - 1);
1136 /* Sets to 1 all of the 'n_bits' bits starting from bit 'dst_ofs' in 'dst'.
1137 * 'dst' is 'dst_len' bytes long.
1139 * If you consider all of 'dst' to be a single unsigned integer in network byte
1140 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1141 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1142 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1145 * Required invariant:
1146 * dst_ofs + n_bits <= dst_len * 8
1149 bitwise_one(void *dst_, unsigned int dst_len, unsigned dst_ofs,
1150 unsigned int n_bits)
1152 uint8_t *dst = dst_;
1158 dst += dst_len - (dst_ofs / 8 + 1);
1162 unsigned int chunk = MIN(n_bits, 8 - dst_ofs);
1164 *dst |= ((1 << chunk) - 1) << dst_ofs;
1174 while (n_bits >= 8) {
1180 *dst |= (1 << n_bits) - 1;
1184 /* Scans the 'n_bits' bits starting from bit 'dst_ofs' in 'dst' for 1-bits.
1185 * Returns false if any 1-bits are found, otherwise true. 'dst' is 'dst_len'
1188 * If you consider all of 'dst' to be a single unsigned integer in network byte
1189 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1190 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1191 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1194 * Required invariant:
1195 * dst_ofs + n_bits <= dst_len * 8
1198 bitwise_is_all_zeros(const void *p_, unsigned int len, unsigned int ofs,
1199 unsigned int n_bits)
1201 const uint8_t *p = p_;
1207 p += len - (ofs / 8 + 1);
1211 unsigned int chunk = MIN(n_bits, 8 - ofs);
1213 if (*p & (((1 << chunk) - 1) << ofs)) {
1225 while (n_bits >= 8) {
1233 if (n_bits && *p & ((1 << n_bits) - 1)) {
1240 /* Copies the 'n_bits' low-order bits of 'value' into the 'n_bits' bits
1241 * starting at bit 'dst_ofs' in 'dst', which is 'dst_len' bytes long.
1243 * If you consider all of 'dst' to be a single unsigned integer in network byte
1244 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1245 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
1246 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
1249 * Required invariants:
1250 * dst_ofs + n_bits <= dst_len * 8
1254 bitwise_put(uint64_t value,
1255 void *dst, unsigned int dst_len, unsigned int dst_ofs,
1256 unsigned int n_bits)
1258 ovs_be64 n_value = htonll(value);
1259 bitwise_copy(&n_value, sizeof n_value, 0,
1260 dst, dst_len, dst_ofs,
1264 /* Returns the value of the 'n_bits' bits starting at bit 'src_ofs' in 'src',
1265 * which is 'src_len' bytes long.
1267 * If you consider all of 'src' to be a single unsigned integer in network byte
1268 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1269 * with value 1 in src[src_len - 1], bit 1 is the bit with value 2, bit 2 is
1270 * the bit with value 4, ..., bit 8 is the bit with value 1 in src[src_len -
1273 * Required invariants:
1274 * src_ofs + n_bits <= src_len * 8
1278 bitwise_get(const void *src, unsigned int src_len,
1279 unsigned int src_ofs, unsigned int n_bits)
1281 ovs_be64 value = htonll(0);
1283 bitwise_copy(src, src_len, src_ofs,
1284 &value, sizeof value, 0,
1286 return ntohll(value);
1307 skip_spaces(const char *s)
1309 while (isspace((unsigned char) *s)) {
1316 scan_int(const char *s, const struct scan_spec *spec, int base, va_list *args)
1318 const char *start = s;
1323 negative = *s == '-';
1324 s += *s == '-' || *s == '+';
1326 if ((!base || base == 16) && *s == '0' && (s[1] == 'x' || s[1] == 'X')) {
1330 base = *s == '0' ? 8 : 10;
1333 if (s - start >= spec->width) {
1339 while (s - start < spec->width) {
1340 int digit = hexit_value(*s);
1342 if (digit < 0 || digit >= base) {
1345 value = value * base + digit;
1357 switch (spec->type) {
1361 *va_arg(*args, char *) = value;
1364 *va_arg(*args, short int *) = value;
1367 *va_arg(*args, int *) = value;
1370 *va_arg(*args, long int *) = value;
1373 *va_arg(*args, long long int *) = value;
1376 *va_arg(*args, intmax_t *) = value;
1378 case SCAN_PTRDIFF_T:
1379 *va_arg(*args, ptrdiff_t *) = value;
1382 *va_arg(*args, size_t *) = value;
1389 skip_digits(const char *s)
1391 while (*s >= '0' && *s <= '9') {
1398 scan_float(const char *s, const struct scan_spec *spec, va_list *args)
1400 const char *start = s;
1406 s += *s == '+' || *s == '-';
1409 s = skip_digits(s + 1);
1411 if (*s == 'e' || *s == 'E') {
1413 s += *s == '+' || *s == '-';
1417 if (s - start > spec->width) {
1418 s = start + spec->width;
1421 copy = xmemdup0(start, s - start);
1422 value = strtold(copy, &tail);
1429 switch (spec->type) {
1433 *va_arg(*args, float *) = value;
1436 *va_arg(*args, double *) = value;
1439 *va_arg(*args, long double *) = value;
1445 case SCAN_PTRDIFF_T:
1453 scan_output_string(const struct scan_spec *spec,
1454 const char *s, size_t n,
1457 if (spec->type != SCAN_DISCARD) {
1458 char *out = va_arg(*args, char *);
1465 scan_string(const char *s, const struct scan_spec *spec, va_list *args)
1469 for (n = 0; n < spec->width; n++) {
1470 if (!s[n] || isspace((unsigned char) s[n])) {
1478 scan_output_string(spec, s, n, args);
1483 parse_scanset(const char *p_, unsigned long *set, bool *complemented)
1485 const uint8_t *p = (const uint8_t *) p_;
1487 *complemented = *p == '^';
1491 bitmap_set1(set, ']');
1495 while (*p && *p != ']') {
1496 if (p[1] == '-' && p[2] != ']' && p[2] > *p) {
1497 bitmap_set_multiple(set, *p, p[2] - *p + 1, true);
1500 bitmap_set1(set, *p++);
1506 return (const char *) p;
1510 scan_set(const char *s, const struct scan_spec *spec, const char **pp,
1513 unsigned long set[BITMAP_N_LONGS(UCHAR_MAX + 1)];
1517 /* Parse the scan set. */
1518 memset(set, 0, sizeof set);
1519 *pp = parse_scanset(*pp, set, &complemented);
1521 /* Parse the data. */
1524 && bitmap_is_set(set, (unsigned char) s[n]) == !complemented
1525 && n < spec->width) {
1531 scan_output_string(spec, s, n, args);
1536 scan_chars(const char *s, const struct scan_spec *spec, va_list *args)
1538 unsigned int n = spec->width == UINT_MAX ? 1 : spec->width;
1540 if (strlen(s) < n) {
1543 if (spec->type != SCAN_DISCARD) {
1544 memcpy(va_arg(*args, char *), s, n);
1549 /* This is an implementation of the standard sscanf() function, with the
1550 * following exceptions:
1552 * - It returns true if the entire format was successfully scanned and
1553 * converted, false if any conversion failed.
1555 * - The standard doesn't define sscanf() behavior when an out-of-range value
1556 * is scanned, e.g. if a "%"PRIi8 conversion scans "-1" or "0x1ff". Some
1557 * implementations consider this an error and stop scanning. This
1558 * implementation never considers an out-of-range value an error; instead,
1559 * it stores the least-significant bits of the converted value in the
1560 * destination, e.g. the value 255 for both examples earlier.
1562 * - Only single-byte characters are supported, that is, the 'l' modifier
1563 * on %s, %[, and %c is not supported. The GNU extension 'a' modifier is
1564 * also not supported.
1566 * - %p is not supported.
1569 ovs_scan(const char *s, const char *format, ...)
1571 const char *const start = s;
1576 va_start(args, format);
1578 while (*p != '\0') {
1579 struct scan_spec spec;
1580 unsigned char c = *p++;
1586 } else if (c != '%') {
1592 } else if (*p == '%') {
1600 /* Parse '*' flag. */
1601 discard = *p == '*';
1604 /* Parse field width. */
1606 while (*p >= '0' && *p <= '9') {
1607 spec.width = spec.width * 10 + (*p++ - '0');
1609 if (spec.width == 0) {
1610 spec.width = UINT_MAX;
1613 /* Parse type modifier. */
1617 spec.type = SCAN_CHAR;
1620 spec.type = SCAN_SHORT;
1626 spec.type = SCAN_INTMAX_T;
1632 spec.type = SCAN_LLONG;
1635 spec.type = SCAN_LONG;
1642 spec.type = SCAN_LLONG;
1647 spec.type = SCAN_PTRDIFF_T;
1652 spec.type = SCAN_SIZE_T;
1657 spec.type = SCAN_INT;
1662 spec.type = SCAN_DISCARD;
1666 if (c != 'c' && c != 'n' && c != '[') {
1671 s = scan_int(s, &spec, 10, &args);
1675 s = scan_int(s, &spec, 0, &args);
1679 s = scan_int(s, &spec, 8, &args);
1683 s = scan_int(s, &spec, 10, &args);
1688 s = scan_int(s, &spec, 16, &args);
1696 s = scan_float(s, &spec, &args);
1700 s = scan_string(s, &spec, &args);
1704 s = scan_set(s, &spec, &p, &args);
1708 s = scan_chars(s, &spec, &args);
1712 if (spec.type != SCAN_DISCARD) {
1713 *va_arg(args, int *) = s - start;
1732 ovs_format_message(int error)
1734 enum { BUFSIZE = sizeof strerror_buffer_get()->s };
1735 char *buffer = strerror_buffer_get()->s;
1737 FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
1738 NULL, error, 0, buffer, BUFSIZE, NULL);
1742 /* Returns a null-terminated string that explains the last error.
1743 * Use this function to get the error string for WINAPI calls. */
1745 ovs_lasterror_to_string(void)
1747 return ovs_format_message(GetLastError());
1751 ftruncate(int fd, off_t length)
1755 error = _chsize_s(fd, length);