2 * Copyright (c) 2008, 2009, 2010, 2011, 2012 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.
28 #include "byte-order.h"
30 #include "openvswitch/types.h"
33 VLOG_DEFINE_THIS_MODULE(util);
35 COVERAGE_DEFINE(util_xalloc);
37 /* argv[0] without directory names. */
38 const char *program_name;
40 /* Ordinarily "" but set to "monitor" for a monitor process or "worker" for a
42 const char *subprogram_name = "";
44 /* --version option output. */
45 static char *program_version;
50 ovs_abort(0, "virtual memory exhausted");
54 xcalloc(size_t count, size_t size)
56 void *p = count && size ? calloc(count, size) : malloc(1);
57 COVERAGE_INC(util_xalloc);
67 return xcalloc(1, size);
73 void *p = malloc(size ? size : 1);
74 COVERAGE_INC(util_xalloc);
82 xrealloc(void *p, size_t size)
84 p = realloc(p, size ? size : 1);
85 COVERAGE_INC(util_xalloc);
93 xmemdup(const void *p_, size_t size)
95 void *p = xmalloc(size);
101 xmemdup0(const char *p_, size_t length)
103 char *p = xmalloc(length + 1);
104 memcpy(p, p_, length);
110 xstrdup(const char *s)
112 return xmemdup0(s, strlen(s));
116 xvasprintf(const char *format, va_list args)
122 va_copy(args2, args);
123 needed = vsnprintf(NULL, 0, format, args);
125 s = xmalloc(needed + 1);
127 vsnprintf(s, needed + 1, format, args2);
134 x2nrealloc(void *p, size_t *n, size_t s)
136 *n = *n == 0 ? 1 : 2 * *n;
137 return xrealloc(p, *n * s);
141 xasprintf(const char *format, ...)
146 va_start(args, format);
147 s = xvasprintf(format, args);
153 /* Similar to strlcpy() from OpenBSD, but it never reads more than 'size - 1'
154 * bytes from 'src' and doesn't return anything. */
156 ovs_strlcpy(char *dst, const char *src, size_t size)
159 size_t len = strnlen(src, size - 1);
160 memcpy(dst, src, len);
165 /* Copies 'src' to 'dst'. Reads no more than 'size - 1' bytes from 'src'.
166 * Always null-terminates 'dst' (if 'size' is nonzero), and writes a zero byte
167 * to every otherwise unused byte in 'dst'.
169 * Except for performance, the following call:
170 * ovs_strzcpy(dst, src, size);
171 * is equivalent to these two calls:
172 * memset(dst, '\0', size);
173 * ovs_strlcpy(dst, src, size);
175 * (Thus, ovs_strzcpy() is similar to strncpy() without some of the pitfalls.)
178 ovs_strzcpy(char *dst, const char *src, size_t size)
181 size_t len = strnlen(src, size - 1);
182 memcpy(dst, src, len);
183 memset(dst + len, '\0', size - len);
187 /* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
188 * nonzero, then it is formatted with ovs_retval_to_string() and appended to
189 * the message inside parentheses. Then, terminates with abort().
191 * This function is preferred to ovs_fatal() in a situation where it would make
192 * sense for a monitoring process to restart the daemon.
194 * 'format' should not end with a new-line, because this function will add one
197 ovs_abort(int err_no, const char *format, ...)
201 va_start(args, format);
202 ovs_error_valist(err_no, format, args);
208 /* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
209 * nonzero, then it is formatted with ovs_retval_to_string() and appended to
210 * the message inside parentheses. Then, terminates with EXIT_FAILURE.
212 * 'format' should not end with a new-line, because this function will add one
215 ovs_fatal(int err_no, const char *format, ...)
219 va_start(args, format);
220 ovs_fatal_valist(err_no, format, args);
223 /* Same as ovs_fatal() except that the arguments are supplied as a va_list. */
225 ovs_fatal_valist(int err_no, const char *format, va_list args)
227 ovs_error_valist(err_no, format, args);
231 /* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
232 * nonzero, then it is formatted with ovs_retval_to_string() and appended to
233 * the message inside parentheses.
235 * 'format' should not end with a new-line, because this function will add one
238 ovs_error(int err_no, const char *format, ...)
242 va_start(args, format);
243 ovs_error_valist(err_no, format, args);
247 /* Same as ovs_error() except that the arguments are supplied as a va_list. */
249 ovs_error_valist(int err_no, const char *format, va_list args)
251 int save_errno = errno;
253 if (subprogram_name[0]) {
254 fprintf(stderr, "%s(%s): ", program_name, subprogram_name);
256 fprintf(stderr, "%s: ", program_name);
259 vfprintf(stderr, format, args);
261 fprintf(stderr, " (%s)", ovs_retval_to_string(err_no));
268 /* Many OVS functions return an int which is one of:
271 * - EOF: end of file (not necessarily an error; depends on the function called)
273 * Returns the appropriate human-readable string. The caller must copy the
274 * string if it wants to hold onto it, as the storage may be overwritten on
275 * subsequent function calls.
278 ovs_retval_to_string(int retval)
280 static char unknown[48];
286 return strerror(retval);
289 return "End of file";
291 snprintf(unknown, sizeof unknown, "***unknown return value: %d***", retval);
295 /* Sets global "program_name" and "program_version" variables. Should
296 * be called at the beginning of main() with "argv[0]" as the argument
299 * 'version' should contain the version of the caller's program. If 'version'
300 * is the same as the VERSION #define, the caller is assumed to be part of Open
301 * vSwitch. Otherwise, it is assumed to be an external program linking against
302 * the Open vSwitch libraries.
304 * The 'date' and 'time' arguments should likely be called with
305 * "__DATE__" and "__TIME__" to use the time the binary was built.
306 * Alternatively, the "set_program_name" macro may be called to do this
310 set_program_name__(const char *argv0, const char *version, const char *date,
313 const char *slash = strrchr(argv0, '/');
314 program_name = slash ? slash + 1 : argv0;
316 free(program_version);
318 if (!strcmp(version, VERSION)) {
319 program_version = xasprintf("%s (Open vSwitch) "VERSION"\n"
321 program_name, date, time);
323 program_version = xasprintf("%s %s\n"
324 "Open vSwitch Library "VERSION"\n"
326 program_name, version, date, time);
330 /* Returns a pointer to a string describing the program version. The
331 * caller must not modify or free the returned string.
334 get_program_version(void)
336 return program_version;
339 /* Print the version information for the program. */
341 ovs_print_version(uint8_t min_ofp, uint8_t max_ofp)
343 printf("%s", program_version);
344 if (min_ofp || max_ofp) {
345 printf("OpenFlow versions %#x:%#x\n", min_ofp, max_ofp);
349 /* Writes the 'size' bytes in 'buf' to 'stream' as hex bytes arranged 16 per
350 * line. Numeric offsets are also included, starting at 'ofs' for the first
351 * byte in 'buf'. If 'ascii' is true then the corresponding ASCII characters
352 * are also rendered alongside. */
354 ovs_hex_dump(FILE *stream, const void *buf_, size_t size,
355 uintptr_t ofs, bool ascii)
357 const uint8_t *buf = buf_;
358 const size_t per_line = 16; /* Maximum bytes per line. */
362 size_t start, end, n;
365 /* Number of bytes on this line. */
366 start = ofs % per_line;
368 if (end - start > size)
373 fprintf(stream, "%08jx ", (uintmax_t) ROUND_DOWN(ofs, per_line));
374 for (i = 0; i < start; i++)
375 fprintf(stream, " ");
377 fprintf(stream, "%02hhx%c",
378 buf[i - start], i == per_line / 2 - 1? '-' : ' ');
381 for (; i < per_line; i++)
382 fprintf(stream, " ");
383 fprintf(stream, "|");
384 for (i = 0; i < start; i++)
385 fprintf(stream, " ");
386 for (; i < end; i++) {
387 int c = buf[i - start];
388 putc(c >= 32 && c < 127 ? c : '.', stream);
390 for (; i < per_line; i++)
391 fprintf(stream, " ");
392 fprintf(stream, "|");
394 fprintf(stream, "\n");
403 str_to_int(const char *s, int base, int *i)
406 bool ok = str_to_llong(s, base, &ll);
412 str_to_long(const char *s, int base, long *li)
415 bool ok = str_to_llong(s, base, &ll);
421 str_to_llong(const char *s, int base, long long *x)
423 int save_errno = errno;
426 *x = strtoll(s, &tail, base);
427 if (errno == EINVAL || errno == ERANGE || tail == s || *tail != '\0') {
438 str_to_uint(const char *s, int base, unsigned int *u)
440 return str_to_int(s, base, (int *) u);
444 str_to_ulong(const char *s, int base, unsigned long *ul)
446 return str_to_long(s, base, (long *) ul);
450 str_to_ullong(const char *s, int base, unsigned long long *ull)
452 return str_to_llong(s, base, (long long *) ull);
455 /* Converts floating-point string 's' into a double. If successful, stores
456 * the double in '*d' and returns true; on failure, stores 0 in '*d' and
459 * Underflow (e.g. "1e-9999") is not considered an error, but overflow
460 * (e.g. "1e9999)" is. */
462 str_to_double(const char *s, double *d)
464 int save_errno = errno;
467 *d = strtod(s, &tail);
468 if (errno == EINVAL || (errno == ERANGE && *d != 0)
469 || tail == s || *tail != '\0') {
479 /* Returns the value of 'c' as a hexadecimal digit. */
484 case '0': case '1': case '2': case '3': case '4':
485 case '5': case '6': case '7': case '8': case '9':
511 /* Returns the integer value of the 'n' hexadecimal digits starting at 's', or
512 * UINT_MAX if one of those "digits" is not really a hex digit. If 'ok' is
513 * nonnull, '*ok' is set to true if the conversion succeeds or to false if a
514 * non-hex digit is detected. */
516 hexits_value(const char *s, size_t n, bool *ok)
522 for (i = 0; i < n; i++) {
523 int hexit = hexit_value(s[i]);
530 value = (value << 4) + hexit;
538 /* Returns the current working directory as a malloc()'d string, or a null
539 * pointer if the current working directory cannot be determined. */
546 /* Get maximum path length or at least a reasonable estimate. */
547 path_max = pathconf(".", _PC_PATH_MAX);
548 size = (path_max < 0 ? 1024
549 : path_max > 10240 ? 10240
552 /* Get current working directory. */
554 char *buf = xmalloc(size);
555 if (getcwd(buf, size)) {
556 return xrealloc(buf, strlen(buf) + 1);
560 if (error != ERANGE) {
561 VLOG_WARN("getcwd failed (%s)", strerror(error));
570 all_slashes_name(const char *s)
572 return xstrdup(s[0] == '/' && s[1] == '/' && s[2] != '/' ? "//"
577 /* Returns the directory name portion of 'file_name' as a malloc()'d string,
578 * similar to the POSIX dirname() function but thread-safe. */
580 dir_name(const char *file_name)
582 size_t len = strlen(file_name);
583 while (len > 0 && file_name[len - 1] == '/') {
586 while (len > 0 && file_name[len - 1] != '/') {
589 while (len > 0 && file_name[len - 1] == '/') {
592 return len ? xmemdup0(file_name, len) : all_slashes_name(file_name);
595 /* Returns the file name portion of 'file_name' as a malloc()'d string,
596 * similar to the POSIX basename() function but thread-safe. */
598 base_name(const char *file_name)
602 end = strlen(file_name);
603 while (end > 0 && file_name[end - 1] == '/') {
608 return all_slashes_name(file_name);
612 while (start > 0 && file_name[start - 1] != '/') {
616 return xmemdup0(file_name + start, end - start);
619 /* If 'file_name' starts with '/', returns a copy of 'file_name'. Otherwise,
620 * returns an absolute path to 'file_name' considering it relative to 'dir',
621 * which itself must be absolute. 'dir' may be null or the empty string, in
622 * which case the current working directory is used.
624 * Returns a null pointer if 'dir' is null and getcwd() fails. */
626 abs_file_name(const char *dir, const char *file_name)
628 if (file_name[0] == '/') {
629 return xstrdup(file_name);
630 } else if (dir && dir[0]) {
631 char *separator = dir[strlen(dir) - 1] == '/' ? "" : "/";
632 return xasprintf("%s%s%s", dir, separator, file_name);
634 char *cwd = get_cwd();
636 char *abs_name = xasprintf("%s/%s", cwd, file_name);
646 /* Pass a value to this function if it is marked with
647 * __attribute__((warn_unused_result)) and you genuinely want to ignore
648 * its return value. (Note that every scalar type can be implicitly
649 * converted to bool.) */
650 void ignore(bool x OVS_UNUSED) { }
652 /* Returns an appropriate delimiter for inserting just before the 0-based item
653 * 'index' in a list that has 'total' items in it. */
655 english_list_delimiter(size_t index, size_t total)
657 return (index == 0 ? ""
658 : index < total - 1 ? ", "
659 : total > 2 ? ", and "
663 /* Given a 32 bit word 'n', calculates floor(log_2('n')). This is equivalent
664 * to finding the bit position of the most significant one bit in 'n'. It is
665 * an error to call this function with 'n' == 0. */
667 log_2_floor(uint32_t n)
671 #if !defined(UINT_MAX) || !defined(UINT32_MAX)
672 #error "Someone screwed up the #includes."
673 #elif __GNUC__ >= 4 && UINT_MAX == UINT32_MAX
674 return 31 - __builtin_clz(n);
679 #define BIN_SEARCH_STEP(BITS) \
680 if (n >= (1 << BITS)) { \
689 #undef BIN_SEARCH_STEP
695 /* Given a 32 bit word 'n', calculates ceil(log_2('n')). It is an error to
696 * call this function with 'n' == 0. */
698 log_2_ceil(uint32_t n)
700 return log_2_floor(n) + !IS_POW2(n);
703 /* Returns the number of trailing 0-bits in 'n', or 32 if 'n' is 0. */
710 #if !defined(UINT_MAX) || !defined(UINT32_MAX)
711 #error "Someone screwed up the #includes."
712 #elif __GNUC__ >= 4 && UINT_MAX == UINT32_MAX
713 return __builtin_ctz(n);
718 #define CTZ_STEP(X) \
736 /* Returns true if the 'n' bytes starting at 'p' are zeros. */
738 is_all_zeros(const uint8_t *p, size_t n)
742 for (i = 0; i < n; i++) {
750 /* Returns true if the 'n' bytes starting at 'p' are 0xff. */
752 is_all_ones(const uint8_t *p, size_t n)
756 for (i = 0; i < n; i++) {
764 /* Copies 'n_bits' bits starting from bit 'src_ofs' in 'src' to the 'n_bits'
765 * starting from bit 'dst_ofs' in 'dst'. 'src' is 'src_len' bytes long and
766 * 'dst' is 'dst_len' bytes long.
768 * If you consider all of 'src' to be a single unsigned integer in network byte
769 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
770 * with value 1 in src[src_len - 1], bit 1 is the bit with value 2, bit 2 is
771 * the bit with value 4, ..., bit 8 is the bit with value 1 in src[src_len -
772 * 2], and so on. Similarly for 'dst'.
774 * Required invariants:
775 * src_ofs + n_bits <= src_len * 8
776 * dst_ofs + n_bits <= dst_len * 8
777 * 'src' and 'dst' must not overlap.
780 bitwise_copy(const void *src_, unsigned int src_len, unsigned int src_ofs,
781 void *dst_, unsigned int dst_len, unsigned int dst_ofs,
784 const uint8_t *src = src_;
787 src += src_len - (src_ofs / 8 + 1);
790 dst += dst_len - (dst_ofs / 8 + 1);
793 if (src_ofs == 0 && dst_ofs == 0) {
794 unsigned int n_bytes = n_bits / 8;
798 memcpy(dst, src, n_bytes);
805 uint8_t mask = (1 << n_bits) - 1;
806 *dst = (*dst & ~mask) | (*src & mask);
810 unsigned int max_copy = 8 - MAX(src_ofs, dst_ofs);
811 unsigned int chunk = MIN(n_bits, max_copy);
812 uint8_t mask = ((1 << chunk) - 1) << dst_ofs;
815 *dst |= ((*src >> src_ofs) << dst_ofs) & mask;
832 /* Zeros the 'n_bits' bits starting from bit 'dst_ofs' in 'dst'. 'dst' is
833 * 'dst_len' bytes long.
835 * If you consider all of 'dst' to be a single unsigned integer in network byte
836 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
837 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
838 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
841 * Required invariant:
842 * dst_ofs + n_bits <= dst_len * 8
845 bitwise_zero(void *dst_, unsigned int dst_len, unsigned dst_ofs,
854 dst += dst_len - (dst_ofs / 8 + 1);
858 unsigned int chunk = MIN(n_bits, 8 - dst_ofs);
860 *dst &= ~(((1 << chunk) - 1) << dst_ofs);
870 while (n_bits >= 8) {
876 *dst &= ~((1 << n_bits) - 1);
880 /* Sets to 1 all of the 'n_bits' bits starting from bit 'dst_ofs' in 'dst'.
881 * 'dst' is 'dst_len' bytes long.
883 * If you consider all of 'dst' to be a single unsigned integer in network byte
884 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
885 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
886 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
889 * Required invariant:
890 * dst_ofs + n_bits <= dst_len * 8
893 bitwise_one(void *dst_, unsigned int dst_len, unsigned dst_ofs,
902 dst += dst_len - (dst_ofs / 8 + 1);
906 unsigned int chunk = MIN(n_bits, 8 - dst_ofs);
908 *dst |= ((1 << chunk) - 1) << dst_ofs;
918 while (n_bits >= 8) {
924 *dst |= (1 << n_bits) - 1;
928 /* Scans the 'n_bits' bits starting from bit 'dst_ofs' in 'dst' for 1-bits.
929 * Returns false if any 1-bits are found, otherwise true. 'dst' is 'dst_len'
932 * If you consider all of 'dst' to be a single unsigned integer in network byte
933 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
934 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
935 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
938 * Required invariant:
939 * dst_ofs + n_bits <= dst_len * 8
942 bitwise_is_all_zeros(const void *p_, unsigned int len, unsigned int ofs,
945 const uint8_t *p = p_;
951 p += len - (ofs / 8 + 1);
955 unsigned int chunk = MIN(n_bits, 8 - ofs);
957 if (*p & (((1 << chunk) - 1) << ofs)) {
969 while (n_bits >= 8) {
977 if (n_bits && *p & ((1 << n_bits) - 1)) {
984 /* Copies the 'n_bits' low-order bits of 'value' into the 'n_bits' bits
985 * starting at bit 'dst_ofs' in 'dst', which is 'dst_len' bytes long.
987 * If you consider all of 'dst' to be a single unsigned integer in network byte
988 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
989 * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
990 * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
993 * Required invariants:
994 * dst_ofs + n_bits <= dst_len * 8
998 bitwise_put(uint64_t value,
999 void *dst, unsigned int dst_len, unsigned int dst_ofs,
1000 unsigned int n_bits)
1002 ovs_be64 n_value = htonll(value);
1003 bitwise_copy(&n_value, sizeof n_value, 0,
1004 dst, dst_len, dst_ofs,
1008 /* Returns the value of the 'n_bits' bits starting at bit 'src_ofs' in 'src',
1009 * which is 'src_len' bytes long.
1011 * If you consider all of 'src' to be a single unsigned integer in network byte
1012 * order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
1013 * with value 1 in src[src_len - 1], bit 1 is the bit with value 2, bit 2 is
1014 * the bit with value 4, ..., bit 8 is the bit with value 1 in src[src_len -
1017 * Required invariants:
1018 * src_ofs + n_bits <= src_len * 8
1022 bitwise_get(const void *src, unsigned int src_len,
1023 unsigned int src_ofs, unsigned int n_bits)
1025 ovs_be64 value = htonll(0);
1027 bitwise_copy(src, src_len, src_ofs,
1028 &value, sizeof value, 0,
1030 return ntohll(value);