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ovs/lib/util.c
Roi Dayan 37848e2188 util: Ignore return code from str_to_uint(). 
Reported by Coverity.
  lib/util.c:795 Unchecked return value (CHECKED_RETURN):

As it's not really bug, wrap it with ignore().

Fixes: 9551e80befc0 ("tests: Use environment variable for default timeout.")
Acked-by: Aaron Conole <aconole@redhat.com>
Acked-by: Kevin Traynor <ktraynor@redhat.com>
Signed-off-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Eelco Chaudron <echaudro@redhat.com>
2025-05-30 10:28:53 +02:00

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/*
* Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <config.h>
#include "util.h"
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <pthread.h>
#include <stdarg.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef __linux__
#include <sys/prctl.h>
#include <sys/utsname.h>
#endif
#include <sys/stat.h>
#include <unistd.h>
#include "bitmap.h"
#include "byte-order.h"
#include "coverage.h"
#include "ovs-rcu.h"
#include "ovs-thread.h"
#include "socket-util.h"
#include "timeval.h"
#include "openvswitch/vlog.h"
#ifdef HAVE_PTHREAD_SET_NAME_NP
#include <pthread_np.h>
#endif
#ifdef _WIN32
#include <shlwapi.h>
#endif
VLOG_DEFINE_THIS_MODULE(util);
#ifdef __linux__
#define LINUX 1
#include <asm/param.h>
#else
#define LINUX 0
#endif
COVERAGE_DEFINE(util_xalloc);
/* argv[0] without directory names. */
char *program_name;
/* Name for the currently running thread or process, for log messages, process
* listings, and debuggers. */
DEFINE_PER_THREAD_MALLOCED_DATA(char *, subprogram_name);
/* --version option output. */
static char *program_version;
/* 'true' if mlockall() succeeded, but doesn't support ONFAULT. */
static bool is_all_memory_locked = false;
/* Buffer used by ovs_strerror() and ovs_format_message(). */
DEFINE_STATIC_PER_THREAD_DATA(struct { char s[128]; },
strerror_buffer,
{ "" });
static char *xreadlink(const char *filename);
void
ovs_assert_failure(const char *where, const char *function,
const char *condition)
{
/* Prevent an infinite loop (or stack overflow) in case VLOG_ABORT happens
* to trigger an assertion failure of its own. */
static int reentry = 0;
switch (reentry++) {
case 0:
VLOG_ABORT("%s: assertion %s failed in %s()",
where, condition, function);
OVS_NOT_REACHED();
case 1:
fprintf(stderr, "%s: assertion %s failed in %s()",
where, condition, function);
abort();
default:
abort();
}
}
void
set_all_memory_locked(void)
{
is_all_memory_locked = true;
}
bool
memory_all_locked(void)
{
return is_all_memory_locked;
}
void
out_of_memory(void)
{
ovs_abort(0, "virtual memory exhausted");
}
void *
xcalloc__(size_t count, size_t size)
{
void *p = count && size ? calloc(count, size) : malloc(1);
if (p == NULL) {
out_of_memory();
}
return p;
}
void *
xzalloc__(size_t size)
{
return xcalloc__(1, size);
}
void *
xmalloc__(size_t size)
{
void *p = malloc(size ? size : 1);
if (p == NULL) {
out_of_memory();
}
return p;
}
void *
xrealloc__(void *p, size_t size)
{
p = realloc(p, size ? size : 1);
if (p == NULL) {
out_of_memory();
}
return p;
}
void *
xcalloc(size_t count, size_t size)
{
COVERAGE_INC(util_xalloc);
return xcalloc__(count, size);
}
void *
xzalloc(size_t size)
{
COVERAGE_INC(util_xalloc);
return xzalloc__(size);
}
void *
xmalloc(size_t size)
{
COVERAGE_INC(util_xalloc);
return xmalloc__(size);
}
void *
xrealloc(void *p, size_t size)
{
COVERAGE_INC(util_xalloc);
return xrealloc__(p, size);
}
void *
xmemdup(const void *p_, size_t size)
{
void *p = xmalloc(size);
nullable_memcpy(p, p_, size);
return p;
}
char *
xmemdup0(const char *p_, size_t length)
{
char *p = xmalloc(length + 1);
memcpy(p, p_, length);
p[length] = '\0';
return p;
}
char *
xstrdup(const char *s)
{
return xmemdup0(s, strlen(s));
}
char * MALLOC_LIKE
nullable_xstrdup(const char *s)
{
return s ? xstrdup(s) : NULL;
}
bool
nullable_string_is_equal(const char *a, const char *b)
{
return a ? b && !strcmp(a, b) : !b;
}
char *
xvasprintf(const char *format, va_list args)
{
va_list args2;
size_t needed;
char *s;
ovs_assert(format);
va_copy(args2, args);
needed = vsnprintf(NULL, 0, format, args);
s = xmalloc(needed + 1);
vsnprintf(s, needed + 1, format, args2);
va_end(args2);
return s;
}
void *
x2nrealloc(void *p, size_t *n, size_t s)
{
*n = *n == 0 ? 1 : 2 * *n;
return xrealloc(p, *n * s);
}
/* Allocates and returns 'size' bytes of memory aligned to 'alignment' bytes.
* 'alignment' must be a power of two and a multiple of sizeof(void *).
*
* Use free_size_align() to free the returned memory block. */
void *
xmalloc_size_align(size_t size, size_t alignment)
{
#ifdef HAVE_POSIX_MEMALIGN
void *p;
int error;
COVERAGE_INC(util_xalloc);
error = posix_memalign(&p, alignment, size ? size : 1);
if (error != 0) {
out_of_memory();
}
return p;
#else
/* Allocate room for:
*
* - Header padding: Up to alignment - 1 bytes, to allow the
* pointer 'q' to be aligned exactly sizeof(void *) bytes before the
* beginning of the alignment.
*
* - Pointer: A pointer to the start of the header padding, to allow us
* to free() the block later.
*
* - User data: 'size' bytes.
*
* - Trailer padding: Enough to bring the user data up to a alignment
* multiple.
*
* +---------------+---------+------------------------+---------+
* | header | pointer | user data | trailer |
* +---------------+---------+------------------------+---------+
* ^ ^ ^
* | | |
* p q r
*
*/
void *p, *r, **q;
bool runt;
if (!IS_POW2(alignment) || (alignment % sizeof(void *) != 0)) {
ovs_abort(0, "Invalid alignment");
}
p = xmalloc((alignment - 1)
+ sizeof(void *)
+ ROUND_UP(size, alignment));
runt = PAD_SIZE((uintptr_t) p, alignment) < sizeof(void *);
/* When the padding size < sizeof(void*), we don't have enough room for
* pointer 'q'. As a reuslt, need to move 'r' to the next alignment.
* So ROUND_UP when xmalloc above, and ROUND_UP again when calculate 'r'
* below.
*/
r = (void *) ROUND_UP((uintptr_t) p + (runt ? alignment : 0), alignment);
q = (void **) r - 1;
*q = p;
return r;
#endif
}
void
free_size_align(void *p)
{
#ifdef HAVE_POSIX_MEMALIGN
free(p);
#else
if (p) {
void **q = (void **) p - 1;
free(*q);
}
#endif
}
/* Allocates and returns 'size' bytes of memory aligned to a cache line and in
* dedicated cache lines. That is, the memory block returned will not share a
* cache line with other data, avoiding "false sharing".
*
* Use free_cacheline() to free the returned memory block. */
void *
xmalloc_cacheline(size_t size)
{
return xmalloc_size_align(size, CACHE_LINE_SIZE);
}
/* Like xmalloc_cacheline() but clears the allocated memory to all zero
* bytes. */
void *
xzalloc_cacheline(size_t size)
{
void *p = xmalloc_cacheline(size);
memset(p, 0, size);
return p;
}
/* Frees a memory block allocated with xmalloc_cacheline() or
* xzalloc_cacheline(). */
void
free_cacheline(void *p)
{
free_size_align(p);
}
void *
xmalloc_pagealign(size_t size)
{
return xmalloc_size_align(size, get_page_size());
}
void
free_pagealign(void *p)
{
free_size_align(p);
}
char *
xasprintf(const char *format, ...)
{
va_list args;
char *s;
va_start(args, format);
s = xvasprintf(format, args);
va_end(args);
return s;
}
/* Similar to strlcpy() from OpenBSD, but it never reads more than 'size - 1'
* bytes from 'src' and doesn't return anything. */
void
ovs_strlcpy(char *dst, const char *src, size_t size)
{
if (size > 0) {
size_t len = strnlen(src, size - 1);
memcpy(dst, src, len);
dst[len] = '\0';
}
}
/* Copies 'src' to 'dst'. Reads no more than 'size - 1' bytes from 'src'.
* Always null-terminates 'dst' (if 'size' is nonzero), and writes a zero byte
* to every otherwise unused byte in 'dst'.
*
* Except for performance, the following call:
* ovs_strzcpy(dst, src, size);
* is equivalent to these two calls:
* memset(dst, '\0', size);
* ovs_strlcpy(dst, src, size);
*
* (Thus, ovs_strzcpy() is similar to strncpy() without some of the pitfalls.)
*/
void
ovs_strzcpy(char *dst, const char *src, size_t size)
{
if (size > 0) {
size_t len = strnlen(src, size - 1);
memcpy(dst, src, len);
memset(dst + len, '\0', size - len);
}
}
/*
* Returns true if 'str' ends with given 'suffix'.
*/
int
string_ends_with(const char *str, const char *suffix)
{
int str_len = strlen(str);
int suffix_len = strlen(suffix);
return (str_len >= suffix_len) &&
(0 == strcmp(str + (str_len - suffix_len), suffix));
}
/* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
* nonzero, then it is formatted with ovs_retval_to_string() and appended to
* the message inside parentheses. Then, terminates with abort().
*
* This function is preferred to ovs_fatal() in a situation where it would make
* sense for a monitoring process to restart the daemon.
*
* 'format' should not end with a new-line, because this function will add one
* itself. */
void
ovs_abort(int err_no, const char *format, ...)
{
va_list args;
va_start(args, format);
ovs_abort_valist(err_no, format, args);
}
/* Same as ovs_abort() except that the arguments are supplied as a va_list. */
void
ovs_abort_valist(int err_no, const char *format, va_list args)
{
ovs_error_valist(err_no, format, args);
abort();
}
/* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
* nonzero, then it is formatted with ovs_retval_to_string() and appended to
* the message inside parentheses. Then, terminates with EXIT_FAILURE.
*
* 'format' should not end with a new-line, because this function will add one
* itself. */
void
ovs_fatal(int err_no, const char *format, ...)
{
va_list args;
va_start(args, format);
ovs_fatal_valist(err_no, format, args);
}
/* Same as ovs_fatal() except that the arguments are supplied as a va_list. */
void
ovs_fatal_valist(int err_no, const char *format, va_list args)
{
ovs_error_valist(err_no, format, args);
exit(EXIT_FAILURE);
}
/* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
* nonzero, then it is formatted with ovs_retval_to_string() and appended to
* the message inside parentheses.
*
* 'format' should not end with a new-line, because this function will add one
* itself. */
void
ovs_error(int err_no, const char *format, ...)
{
va_list args;
va_start(args, format);
ovs_error_valist(err_no, format, args);
va_end(args);
}
/* Same as ovs_error() except that the arguments are supplied as a va_list. */
void
ovs_error_valist(int err_no, const char *format, va_list args)
{
const char *subprogram_name = get_subprogram_name();
int save_errno = errno;
if (subprogram_name[0]) {
fprintf(stderr, "%s(%s): ", program_name, subprogram_name);
} else {
fprintf(stderr, "%s: ", program_name);
}
vfprintf(stderr, format, args);
if (err_no != 0) {
fprintf(stderr, " (%s)", ovs_retval_to_string(err_no));
}
putc('\n', stderr);
errno = save_errno;
}
/* Many OVS functions return an int which is one of:
* - 0: no error yet
* - >0: errno value
* - EOF: end of file (not necessarily an error; depends on the function called)
*
* Returns the appropriate human-readable string. The caller must copy the
* string if it wants to hold onto it, as the storage may be overwritten on
* subsequent function calls.
*/
const char *
ovs_retval_to_string(int retval)
{
return (!retval ? ""
: retval == EOF ? "End of file"
: ovs_strerror(retval));
}
/* This function returns the string describing the error number in 'error'
* for POSIX platforms. For Windows, this function can be used for C library
* calls. For socket calls that are also used in Windows, use sock_strerror()
* instead. For WINAPI calls, look at ovs_lasterror_to_string(). */
const char *
ovs_strerror(int error)
{
enum { BUFSIZE = sizeof strerror_buffer_get()->s };
int save_errno;
char *buffer;
char *s;
if (error == 0) {
/*
* strerror(0) varies among platforms:
*
* Success
* No error
* Undefined error: 0
*
* We want to provide a consistent result here because
* our testsuite has test cases which strictly matches
* log messages containing this string.
*/
return "Success";
}
save_errno = errno;
buffer = strerror_buffer_get()->s;
#if STRERROR_R_CHAR_P
/* GNU style strerror_r() might return an immutable static string, or it
* might write and return 'buffer', but in either case we can pass the
* returned string directly to the caller. */
s = strerror_r(error, buffer, BUFSIZE);
#else /* strerror_r() returns an int. */
s = buffer;
if (strerror_r(error, buffer, BUFSIZE)) {
/* strerror_r() is only allowed to fail on ERANGE (because the buffer
* is too short). We don't check the actual failure reason because
* POSIX requires strerror_r() to return the error but old glibc
* (before 2.13) returns -1 and sets errno. */
snprintf(buffer, BUFSIZE, "Unknown error %d", error);
}
#endif
errno = save_errno;
return s;
}
/* Sets global "program_name" and "program_version" variables. Should
* be called at the beginning of main() with "argv[0]" as the argument
* to 'argv0'.
*
* 'version' should contain the version of the caller's program. If 'version'
* is the same as the VERSION #define, the caller is assumed to be part of Open
* vSwitch. Otherwise, it is assumed to be an external program linking against
* the Open vSwitch libraries.
*
*/
void
ovs_set_program_name(const char *argv0, const char *version)
{
char *basename;
#ifdef _WIN32
size_t max_len = strlen(argv0) + 1;
SetErrorMode(GetErrorMode() | SEM_NOGPFAULTERRORBOX);
#if _MSC_VER < 1900
/* This function is deprecated from 1900 (Visual Studio 2015) */
_set_output_format(_TWO_DIGIT_EXPONENT);
#endif
basename = xmalloc(max_len);
_splitpath_s(argv0, NULL, 0, NULL, 0, basename, max_len, NULL, 0);
#else
const char *slash = strrchr(argv0, '/');
basename = xstrdup(slash ? slash + 1 : argv0);
#endif
assert_single_threaded();
free(program_name);
/* Remove libtool prefix, if it is there */
if (strncmp(basename, "lt-", 3) == 0) {
char *tmp_name = basename;
basename = xstrdup(basename + 3);
free(tmp_name);
}
program_name = basename;
free(program_version);
if (!strcmp(version, VERSION VERSION_SUFFIX)) {
program_version = xasprintf("%s (Open vSwitch) "VERSION
VERSION_SUFFIX,
program_name);
} else {
program_version = xasprintf("%s %s\n"
"Open vSwitch Library "VERSION
VERSION_SUFFIX,
program_name, version);
}
}
/* Returns the name of the currently running thread or process. */
const char *
get_subprogram_name(void)
{
const char *name = subprogram_name_get();
return name ? name : "";
}
/* Sets 'subprogram_name' as the name of the currently running thread or
* process. (This appears in log messages and may also be visible in system
* process listings and debuggers.) */
void
set_subprogram_name(const char *subprogram_name)
{
char *pname = xstrdup(subprogram_name ? subprogram_name : program_name);
free(subprogram_name_set(pname));
#if HAVE_GLIBC_PTHREAD_SETNAME_NP
/* The maximum supported thread name including '\0' is 16.
* Add '>' at 0th position to highlight that the name was truncated. */
if (strlen(pname) > 15) {
memmove(pname, &pname[strlen(pname) - 15], 15 + 1);
pname[0] = '>';
}
pthread_setname_np(pthread_self(), pname);
#elif HAVE_NETBSD_PTHREAD_SETNAME_NP
pthread_setname_np(pthread_self(), "%s", pname);
#elif HAVE_PTHREAD_SET_NAME_NP
pthread_set_name_np(pthread_self(), pname);
#endif
}
unsigned int
get_page_size(void)
{
static unsigned int cached;
if (!cached) {
#ifndef _WIN32
long int value = sysconf(_SC_PAGESIZE);
#else
long int value;
SYSTEM_INFO sysinfo;
GetSystemInfo(&sysinfo);
value = sysinfo.dwPageSize;
#endif
if (value >= 0) {
cached = value;
}
}
return cached;
}
/* Returns the time at which the system booted, as the number of milliseconds
* since the epoch, or 0 if the time of boot cannot be determined. */
long long int
get_boot_time(void)
{
static long long int cache_expiration = LLONG_MIN;
static long long int boot_time;
ovs_assert(LINUX);
if (time_msec() >= cache_expiration) {
static const char stat_file[] = "/proc/stat";
char line[128];
FILE *stream;
cache_expiration = time_msec() + 5 * 1000;
stream = fopen(stat_file, "r");
if (!stream) {
VLOG_ERR_ONCE("%s: open failed (%s)",
stat_file, ovs_strerror(errno));
return boot_time;
}
while (fgets(line, sizeof line, stream)) {
long long int btime;
if (ovs_scan(line, "btime %lld", &btime)) {
boot_time = btime * 1000;
goto done;
}
}
VLOG_ERR_ONCE("%s: btime not found", stat_file);
done:
fclose(stream);
}
return boot_time;
}
/* This is a wrapper for setting timeout in control utils.
* The value of OVS_CTL_TIMEOUT environment variable will be used by
* default if 'secs' is not specified. */
void
ctl_timeout_setup(unsigned int secs)
{
if (!secs) {
char *env = getenv("OVS_CTL_TIMEOUT");
if (env && env[0]) {
ignore(str_to_uint(env, 10, &secs));
}
}
if (secs) {
time_alarm(secs);
}
}
/* Returns a pointer to a string describing the program version. The
* caller must not modify or free the returned string.
*/
const char *
ovs_get_program_version(void)
{
return program_version;
}
/* Returns a pointer to a string describing the program name. The
* caller must not modify or free the returned string.
*/
const char *
ovs_get_program_name(void)
{
return program_name;
}
/* Print the version information for the program. */
void
ovs_print_version(uint8_t min_ofp, uint8_t max_ofp)
{
printf("%s\n", program_version);
if (min_ofp || max_ofp) {
printf("OpenFlow versions %#x:%#x\n", min_ofp, max_ofp);
}
}
/* Writes the 'size' bytes in 'buf' to 'stream' as hex bytes arranged 16 per
* line. Numeric offsets are also included, starting at 'ofs' for the first
* byte in 'buf'. If 'ascii' is true then the corresponding ASCII characters
* are also rendered alongside. */
void
ovs_hex_dump(FILE *stream, const void *buf_, size_t size,
uintptr_t ofs, bool ascii)
{
const uint8_t *buf = buf_;
const size_t per_line = 16; /* Maximum bytes per line. */
while (size > 0) {
size_t i;
/* Number of bytes on this line. */
size_t start = ofs % per_line;
size_t end = per_line;
if (end - start > size) {
end = start + size;
}
size_t n = end - start;
/* Print line. */
fprintf(stream, "%08"PRIxMAX" ",
(uintmax_t) ROUND_DOWN(ofs, per_line));
for (i = 0; i < start; i++) {
fprintf(stream, " ");
}
for (; i < end; i++) {
fprintf(stream, "%c%02x",
i == per_line / 2 ? '-' : ' ', buf[i - start]);
}
if (ascii) {
fprintf(stream, " ");
for (; i < per_line; i++) {
fprintf(stream, " ");
}
fprintf(stream, "|");
for (i = 0; i < start; i++) {
fprintf(stream, " ");
}
for (; i < end; i++) {
int c = buf[i - start];
putc(c >= 32 && c < 127 ? c : '.', stream);
}
for (; i < per_line; i++) {
fprintf(stream, " ");
}
fprintf(stream, "|");
}
fprintf(stream, "\n");
ofs += n;
buf += n;
size -= n;
}
}
bool
str_to_int(const char *s, int base, int *i)
{
long long ll;
bool ok = str_to_llong(s, base, &ll);
if (!ok || ll < INT_MIN || ll > INT_MAX) {
*i = 0;
return false;
}
*i = ll;
return true;
}
bool
str_to_long(const char *s, int base, long *li)
{
long long ll;
bool ok = str_to_llong(s, base, &ll);
if (!ok || ll < LONG_MIN || ll > LONG_MAX) {
*li = 0;
return false;
}
*li = ll;
return true;
}
bool
str_to_llong(const char *s, int base, long long *x)
{
char *tail;
bool ok = str_to_llong_with_tail(s, &tail, base, x);
if (*tail != '\0') {
*x = 0;
return false;
}
return ok;
}
bool
str_to_llong_with_tail(const char *s, char **tail, int base, long long *x)
{
int save_errno = errno;
errno = 0;
*x = strtoll(s, tail, base);
if (errno == EINVAL || errno == ERANGE || *tail == s) {
errno = save_errno;
*x = 0;
return false;
} else {
errno = save_errno;
return true;
}
}
bool
str_to_uint(const char *s, int base, unsigned int *u)
{
long long ll;
bool ok = str_to_llong(s, base, &ll);
if (!ok || ll < 0 || ll > UINT_MAX) {
*u = 0;
return false;
} else {
*u = ll;
return true;
}
}
bool
str_to_ullong(const char *s, int base, unsigned long long *x)
{
int save_errno = errno;
char *tail;
errno = 0;
*x = strtoull(s, &tail, base);
if (errno == EINVAL || errno == ERANGE || tail == s || *tail != '\0') {
errno = save_errno;
*x = 0;
return false;
} else {
errno = save_errno;
return true;
}
}
bool
str_to_llong_range(const char *s, int base, long long *begin,
long long *end)
{
char *tail;
if (str_to_llong_with_tail(s, &tail, base, begin)
&& *tail == '-'
&& str_to_llong(tail + 1, base, end)) {
return true;
}
*begin = 0;
*end = 0;
return false;
}
/* Converts floating-point string 's' into a double. If successful, stores
* the double in '*d' and returns true; on failure, stores 0 in '*d' and
* returns false.
*
* Underflow (e.g. "1e-9999") is not considered an error, but overflow
* (e.g. "1e9999)" is. */
bool
str_to_double(const char *s, double *d)
{
int save_errno = errno;
char *tail;
errno = 0;
*d = strtod(s, &tail);
if (errno == EINVAL || (errno == ERANGE && *d != 0)
|| tail == s || *tail != '\0') {
errno = save_errno;
*d = 0;
return false;
} else {
errno = save_errno;
return true;
}
}
/* Returns the value of 'c' as a hexadecimal digit. */
int
hexit_value(unsigned char c)
{
static const signed char tbl[UCHAR_MAX + 1] = {
#define TBL(x) \
( x >= '0' && x <= '9' ? x - '0' \
: x >= 'a' && x <= 'f' ? x - 'a' + 0xa \
: x >= 'A' && x <= 'F' ? x - 'A' + 0xa \
: -1)
#define TBL0(x) TBL(x), TBL((x) + 1), TBL((x) + 2), TBL((x) + 3)
#define TBL1(x) TBL0(x), TBL0((x) + 4), TBL0((x) + 8), TBL0((x) + 12)
#define TBL2(x) TBL1(x), TBL1((x) + 16), TBL1((x) + 32), TBL1((x) + 48)
TBL2(0), TBL2(64), TBL2(128), TBL2(192)
};
return tbl[c];
}
/* Returns the integer value of the 'n' hexadecimal digits starting at 's', or
* UINTMAX_MAX if one of those "digits" is not really a hex digit. Sets '*ok'
* to true if the conversion succeeds or to false if a non-hex digit is
* detected. */
uintmax_t
hexits_value(const char *s, size_t n, bool *ok)
{
uintmax_t value;
size_t i;
value = 0;
for (i = 0; i < n; i++) {
int hexit = hexit_value(s[i]);
if (hexit < 0) {
*ok = false;
return UINTMAX_MAX;
}
value = (value << 4) + hexit;
}
*ok = true;
return value;
}
/* Parses the string in 's' as an integer in either hex or decimal format and
* puts the result right justified in the array 'valuep' that is 'field_width'
* big. If the string is in hex format, the value may be arbitrarily large;
* integers are limited to 64-bit values. (The rationale is that decimal is
* likely to represent a number and 64 bits is a reasonable maximum whereas
* hex could either be a number or a byte string.)
*
* On return 'tail' points to the first character in the string that was
* not parsed as part of the value. ERANGE is returned if the value is too
* large to fit in the given field. */
int
parse_int_string(const char *s, uint8_t *valuep, int field_width, char **tail)
{
unsigned long long int integer;
int i;
if (!strncmp(s, "0x", 2) || !strncmp(s, "0X", 2)) {
uint8_t *hexit_str;
int len = 0;
int val_idx;
int err = 0;
s += 2;
hexit_str = xmalloc(field_width * 2);
for (;;) {
uint8_t hexit;
bool ok;
s += strspn(s, " \t\r\n");
hexit = hexits_value(s, 1, &ok);
if (!ok) {
*tail = CONST_CAST(char *, s);
break;
}
if (hexit != 0 || len) {
if (DIV_ROUND_UP(len + 1, 2) > field_width) {
err = ERANGE;
goto free;
}
hexit_str[len] = hexit;
len++;
}
s++;
}
val_idx = field_width;
for (i = len - 1; i >= 0; i -= 2) {
val_idx--;
valuep[val_idx] = hexit_str[i];
if (i > 0) {
valuep[val_idx] += hexit_str[i - 1] << 4;
}
}
memset(valuep, 0, val_idx);
free:
free(hexit_str);
return err;
}
errno = 0;
integer = strtoull(s, tail, 0);
if (errno || s == *tail) {
return errno ? errno : EINVAL;
}
for (i = field_width - 1; i >= 0; i--) {
valuep[i] = integer;
integer >>= 8;
}
if (integer) {
return ERANGE;
}
return 0;
}
/* Returns the current working directory as a malloc()'d string, or a null
* pointer if the current working directory cannot be determined. */
char *
get_cwd(void)
{
long int path_max;
size_t size;
/* Get maximum path length or at least a reasonable estimate. */
#ifndef _WIN32
path_max = pathconf(".", _PC_PATH_MAX);
#else
path_max = MAX_PATH;
#endif
size = (path_max < 0 ? 1024
: path_max > 10240 ? 10240
: path_max);
/* Get current working directory. */
for (;;) {
char *buf = xmalloc(size);
if (getcwd(buf, size)) {
return xrealloc(buf, strlen(buf) + 1);
} else {
int error = errno;
free(buf);
if (error != ERANGE) {
VLOG_WARN("getcwd failed (%s)", ovs_strerror(error));
return NULL;
}
size *= 2;
}
}
}
static char *
all_slashes_name(const char *s)
{
return xstrdup(s[0] == '/' && s[1] == '/' && s[2] != '/' ? "//"
: s[0] == '/' ? "/"
: ".");
}
#ifndef _WIN32
/* Returns the directory name portion of 'file_name' as a malloc()'d string,
* similar to the POSIX dirname() function but thread-safe. */
char *
dir_name(const char *file_name)
{
size_t len = strlen(file_name);
while (len > 0 && file_name[len - 1] == '/') {
len--;
}
while (len > 0 && file_name[len - 1] != '/') {
len--;
}
while (len > 0 && file_name[len - 1] == '/') {
len--;
}
return len ? xmemdup0(file_name, len) : all_slashes_name(file_name);
}
/* Returns the file name portion of 'file_name' as a malloc()'d string,
* similar to the POSIX basename() function but thread-safe. */
char *
base_name(const char *file_name)
{
size_t end, start;
end = strlen(file_name);
while (end > 0 && file_name[end - 1] == '/') {
end--;
}
if (!end) {
return all_slashes_name(file_name);
}
start = end;
while (start > 0 && file_name[start - 1] != '/') {
start--;
}
return xmemdup0(file_name + start, end - start);
}
#endif /* _WIN32 */
bool
is_file_name_absolute(const char *fn)
{
#ifdef _WIN32
/* Use platform specific API */
return !PathIsRelative(fn);
#else
/* An absolute path begins with /. */
return fn[0] == '/';
#endif
}
/* If 'file_name' is absolute, returns a copy of 'file_name'. Otherwise,
* returns an absolute path to 'file_name' considering it relative to 'dir',
* which itself must be absolute. 'dir' may be null or the empty string, in
* which case the current working directory is used.
*
* Returns a null pointer if 'dir' is null and getcwd() fails. */
char *
abs_file_name(const char *dir, const char *file_name)
{
/* If it's already absolute, return a copy. */
if (is_file_name_absolute(file_name)) {
return xstrdup(file_name);
}
/* If a base dir was supplied, use it. We assume, without checking, that
* the base dir is absolute.*/
if (dir && dir[0]) {
char *separator = dir[strlen(dir) - 1] == '/' ? "" : "/";
return xasprintf("%s%s%s", dir, separator, file_name);
}
#if _WIN32
/* It's a little complicated to make an absolute path on Windows because a
* relative path might still specify a drive letter. The OS has a function
* to do the job for us, so use it. */
char abs_path[MAX_PATH];
DWORD n = GetFullPathName(file_name, sizeof abs_path, abs_path, NULL);
return n > 0 && n <= sizeof abs_path ? xmemdup0(abs_path, n) : NULL;
#else
/* Outside Windows, do the job ourselves. */
char *cwd = get_cwd();
if (!cwd) {
return NULL;
}
char *abs_name = xasprintf("%s/%s", cwd, file_name);
free(cwd);
return abs_name;
#endif
}
/* Like readlink(), but returns the link name as a null-terminated string in
* allocated memory that the caller must eventually free (with free()).
* Returns NULL on error, in which case errno is set appropriately. */
static char *
xreadlink(const char *filename)
{
#ifdef _WIN32
errno = ENOENT;
return NULL;
#else
size_t size;
for (size = 64; ; size *= 2) {
char *buf = xmalloc(size);
ssize_t retval = readlink(filename, buf, size);
int error = errno;
if (retval >= 0 && retval < size) {
buf[retval] = '\0';
return buf;
}
free(buf);
if (retval < 0) {
errno = error;
return NULL;
}
}
#endif
}
/* Returns a version of 'filename' with symlinks in the final component
* dereferenced. This differs from realpath() in that:
*
* - 'filename' need not exist.
*
* - If 'filename' does exist as a symlink, its referent need not exist.
*
* - Only symlinks in the final component of 'filename' are dereferenced.
*
* For Windows platform, this function returns a string that has the same
* value as the passed string.
*
* The caller must eventually free the returned string (with free()). */
char *
follow_symlinks(const char *filename)
{
#ifndef _WIN32
struct stat s;
char *fn;
int i;
fn = xstrdup(filename);
for (i = 0; i < 10; i++) {
char *linkname;
char *next_fn;
if (lstat(fn, &s) != 0 || !S_ISLNK(s.st_mode)) {
return fn;
}
linkname = xreadlink(fn);
if (!linkname) {
VLOG_WARN("%s: readlink failed (%s)",
filename, ovs_strerror(errno));
return fn;
}
if (linkname[0] == '/') {
/* Target of symlink is absolute so use it raw. */
next_fn = linkname;
} else {
/* Target of symlink is relative so add to 'fn''s directory. */
char *dir = dir_name(fn);
if (!strcmp(dir, ".")) {
next_fn = linkname;
} else {
char *separator = dir[strlen(dir) - 1] == '/' ? "" : "/";
next_fn = xasprintf("%s%s%s", dir, separator, linkname);
free(linkname);
}
free(dir);
}
free(fn);
fn = next_fn;
}
VLOG_WARN("%s: too many levels of symlinks", filename);
free(fn);
#endif
return xstrdup(filename);
}
/* Pass a value to this function if it is marked with
* __attribute__((warn_unused_result)) and you genuinely want to ignore
* its return value. (Note that every scalar type can be implicitly
* converted to bool.) */
void ignore(bool x OVS_UNUSED) { }
/* Returns an appropriate delimiter for inserting just before the 0-based item
* 'index' in a list that has 'total' items in it. */
const char *
english_list_delimiter(size_t index, size_t total)
{
return (index == 0 ? ""
: index < total - 1 ? ", "
: total > 2 ? ", and "
: " and ");
}
/* Returns the number of trailing 0-bits in 'n'. Undefined if 'n' == 0. */
#if __GNUC__ >= 4 || _MSC_VER
/* Defined inline in util.h. */
#else
/* Returns the number of trailing 0-bits in 'n'. Undefined if 'n' == 0. */
int
raw_ctz(uint64_t n)
{
uint64_t k;
int count = 63;
#define CTZ_STEP(X) \
k = n << (X); \
if (k) { \
count -= X; \
n = k; \
}
CTZ_STEP(32);
CTZ_STEP(16);
CTZ_STEP(8);
CTZ_STEP(4);
CTZ_STEP(2);
CTZ_STEP(1);
#undef CTZ_STEP
return count;
}
/* Returns the number of leading 0-bits in 'n'. Undefined if 'n' == 0. */
int
raw_clz64(uint64_t n)
{
uint64_t k;
int count = 63;
#define CLZ_STEP(X) \
k = n >> (X); \
if (k) { \
count -= X; \
n = k; \
}
CLZ_STEP(32);
CLZ_STEP(16);
CLZ_STEP(8);
CLZ_STEP(4);
CLZ_STEP(2);
CLZ_STEP(1);
#undef CLZ_STEP
return count;
}
#endif
#if NEED_COUNT_1BITS_8
#define INIT1(X) \
((((X) & (1 << 0)) != 0) + \
(((X) & (1 << 1)) != 0) + \
(((X) & (1 << 2)) != 0) + \
(((X) & (1 << 3)) != 0) + \
(((X) & (1 << 4)) != 0) + \
(((X) & (1 << 5)) != 0) + \
(((X) & (1 << 6)) != 0) + \
(((X) & (1 << 7)) != 0))
#define INIT2(X) INIT1(X), INIT1((X) + 1)
#define INIT4(X) INIT2(X), INIT2((X) + 2)
#define INIT8(X) INIT4(X), INIT4((X) + 4)
#define INIT16(X) INIT8(X), INIT8((X) + 8)
#define INIT32(X) INIT16(X), INIT16((X) + 16)
#define INIT64(X) INIT32(X), INIT32((X) + 32)
const uint8_t count_1bits_8[256] = {
INIT64(0), INIT64(64), INIT64(128), INIT64(192)
};
#endif
/* Returns true if the 'n' bytes starting at 'p' are 'byte'. */
bool
is_all_byte(const void *p_, size_t n, uint8_t byte)
{
const uint8_t *p = p_;
size_t i;
for (i = 0; i < n; i++) {
if (p[i] != byte) {
return false;
}
}
return true;
}
/* Returns true if the 'n' bytes starting at 'p' are zeros. */
bool
is_all_zeros(const void *p, size_t n)
{
return is_all_byte(p, n, 0);
}
/* Returns true if the 'n' bytes starting at 'p' are 0xff. */
bool
is_all_ones(const void *p, size_t n)
{
return is_all_byte(p, n, 0xff);
}
/* *dst |= *src for 'n' bytes. */
void
or_bytes(void *dst_, const void *src_, size_t n)
{
const uint8_t *src = src_;
uint8_t *dst = dst_;
size_t i;
for (i = 0; i < n; i++) {
*dst++ |= *src++;
}
}
/* Copies 'n_bits' bits starting from bit 'src_ofs' in 'src' to the 'n_bits'
* starting from bit 'dst_ofs' in 'dst'. 'src' is 'src_len' bytes long and
* 'dst' is 'dst_len' bytes long.
*
* If you consider all of 'src' to be a single unsigned integer in network byte
* order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
* with value 1 in src[src_len - 1], bit 1 is the bit with value 2, bit 2 is
* the bit with value 4, ..., bit 8 is the bit with value 1 in src[src_len -
* 2], and so on. Similarly for 'dst'.
*
* Required invariants:
* src_ofs + n_bits <= src_len * 8
* dst_ofs + n_bits <= dst_len * 8
* 'src' and 'dst' must not overlap.
*/
void
bitwise_copy(const void *src_, unsigned int src_len, unsigned int src_ofs,
void *dst_, unsigned int dst_len, unsigned int dst_ofs,
unsigned int n_bits)
{
const uint8_t *src = src_;
uint8_t *dst = dst_;
src += src_len - (src_ofs / 8 + 1);
src_ofs %= 8;
dst += dst_len - (dst_ofs / 8 + 1);
dst_ofs %= 8;
if (src_ofs == 0 && dst_ofs == 0) {
unsigned int n_bytes = n_bits / 8;
if (n_bytes) {
dst -= n_bytes - 1;
src -= n_bytes - 1;
memcpy(dst, src, n_bytes);
n_bits %= 8;
src--;
dst--;
}
if (n_bits) {
uint8_t mask = (1 << n_bits) - 1;
*dst = (*dst & ~mask) | (*src & mask);
}
} else {
while (n_bits > 0) {
unsigned int max_copy = 8 - MAX(src_ofs, dst_ofs);
unsigned int chunk = MIN(n_bits, max_copy);
uint8_t mask = ((1 << chunk) - 1) << dst_ofs;
*dst &= ~mask;
*dst |= ((*src >> src_ofs) << dst_ofs) & mask;
src_ofs += chunk;
if (src_ofs == 8) {
src--;
src_ofs = 0;
}
dst_ofs += chunk;
if (dst_ofs == 8) {
dst--;
dst_ofs = 0;
}
n_bits -= chunk;
}
}
}
/* Zeros the 'n_bits' bits starting from bit 'dst_ofs' in 'dst'. 'dst' is
* 'dst_len' bytes long.
*
* If you consider all of 'dst' to be a single unsigned integer in network byte
* order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
* with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
* the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
* 2], and so on.
*
* Required invariant:
* dst_ofs + n_bits <= dst_len * 8
*/
void
bitwise_zero(void *dst_, unsigned int dst_len, unsigned dst_ofs,
unsigned int n_bits)
{
uint8_t *dst = dst_;
if (!n_bits) {
return;
}
dst += dst_len - (dst_ofs / 8 + 1);
dst_ofs %= 8;
if (dst_ofs) {
unsigned int chunk = MIN(n_bits, 8 - dst_ofs);
*dst &= ~(((1 << chunk) - 1) << dst_ofs);
n_bits -= chunk;
if (!n_bits) {
return;
}
dst--;
}
while (n_bits >= 8) {
*dst-- = 0;
n_bits -= 8;
}
if (n_bits) {
*dst &= ~((1 << n_bits) - 1);
}
}
/* Sets to 1 all of the 'n_bits' bits starting from bit 'dst_ofs' in 'dst'.
* 'dst' is 'dst_len' bytes long.
*
* If you consider all of 'dst' to be a single unsigned integer in network byte
* order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
* with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
* the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
* 2], and so on.
*
* Required invariant:
* dst_ofs + n_bits <= dst_len * 8
*/
void
bitwise_one(void *dst_, unsigned int dst_len, unsigned dst_ofs,
unsigned int n_bits)
{
uint8_t *dst = dst_;
if (!n_bits) {
return;
}
dst += dst_len - (dst_ofs / 8 + 1);
dst_ofs %= 8;
if (dst_ofs) {
unsigned int chunk = MIN(n_bits, 8 - dst_ofs);
*dst |= ((1 << chunk) - 1) << dst_ofs;
n_bits -= chunk;
if (!n_bits) {
return;
}
dst--;
}
while (n_bits >= 8) {
*dst-- = 0xff;
n_bits -= 8;
}
if (n_bits) {
*dst |= (1 << n_bits) - 1;
}
}
/* Scans the 'n_bits' bits starting from bit 'dst_ofs' in 'dst' for 1-bits.
* Returns false if any 1-bits are found, otherwise true. 'dst' is 'dst_len'
* bytes long.
*
* If you consider all of 'dst' to be a single unsigned integer in network byte
* order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
* with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
* the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
* 2], and so on.
*
* Required invariant:
* dst_ofs + n_bits <= dst_len * 8
*/
bool
bitwise_is_all_zeros(const void *p_, unsigned int len, unsigned int ofs,
unsigned int n_bits)
{
const uint8_t *p = p_;
if (!n_bits) {
return true;
}
p += len - (ofs / 8 + 1);
ofs %= 8;
if (ofs) {
unsigned int chunk = MIN(n_bits, 8 - ofs);
if (*p & (((1 << chunk) - 1) << ofs)) {
return false;
}
n_bits -= chunk;
if (!n_bits) {
return true;
}
p--;
}
while (n_bits >= 8) {
if (*p) {
return false;
}
n_bits -= 8;
p--;
}
if (n_bits && *p & ((1 << n_bits) - 1)) {
return false;
}
return true;
}
/* Scans the bits in 'p' that have bit offsets 'start' (inclusive) through
* 'end' (exclusive) for the first bit with value 'target'. If one is found,
* returns its offset, otherwise 'end'. 'p' is 'len' bytes long.
*
* If you consider all of 'p' to be a single unsigned integer in network byte
* order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
* with value 1 in p[len - 1], bit 1 is the bit with value 2, bit 2 is the bit
* with value 4, ..., bit 8 is the bit with value 1 in p[len - 2], and so on.
*
* Required invariant:
* start <= end
*/
unsigned int
bitwise_scan(const void *p, unsigned int len, bool target, unsigned int start,
unsigned int end)
{
unsigned int ofs;
for (ofs = start; ofs < end; ofs++) {
if (bitwise_get_bit(p, len, ofs) == target) {
break;
}
}
return ofs;
}
/* Scans the bits in 'p' that have bit offsets 'start' (inclusive) through
* 'end' (exclusive) for the first bit with value 'target', in reverse order.
* If one is found, returns its offset, otherwise 'end'. 'p' is 'len' bytes
* long.
*
* If you consider all of 'p' to be a single unsigned integer in network byte
* order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
* with value 1 in p[len - 1], bit 1 is the bit with value 2, bit 2 is the bit
* with value 4, ..., bit 8 is the bit with value 1 in p[len - 2], and so on.
*
* To scan an entire bit array in reverse order, specify start == len * 8 - 1
* and end == -1, in which case the return value is nonnegative if successful
* and -1 if no 'target' match is found.
*
* Required invariant:
* start >= end
*/
int
bitwise_rscan(const void *p, unsigned int len, bool target, int start, int end)
{
const uint8_t *s = p;
int start_byte = len - (start / 8 + 1);
int end_byte = len - (end / 8 + 1);
int ofs_byte;
int ofs;
uint8_t the_byte;
/* Find the target in the start_byte from starting offset */
ofs_byte = start_byte;
the_byte = s[ofs_byte];
for (ofs = start % 8; ofs >= 0; ofs--) {
if (((the_byte & (1u << ofs)) != 0) == target) {
break;
}
}
if (ofs < 0) {
/* Target not found in start byte, continue searching byte by byte */
for (ofs_byte = start_byte + 1; ofs_byte <= end_byte; ofs_byte++) {
if ((target && s[ofs_byte])
|| (!target && (s[ofs_byte] != 0xff))) {
break;
}
}
if (ofs_byte > end_byte) {
return end;
}
the_byte = s[ofs_byte];
/* Target is in the_byte, find it bit by bit */
for (ofs = 7; ofs >= 0; ofs--) {
if (((the_byte & (1u << ofs)) != 0) == target) {
break;
}
}
}
int ret = (len - ofs_byte) * 8 - (8 - ofs);
if (ret < end) {
return end;
}
return ret;
}
/* Copies the 'n_bits' low-order bits of 'value' into the 'n_bits' bits
* starting at bit 'dst_ofs' in 'dst', which is 'dst_len' bytes long.
*
* If you consider all of 'dst' to be a single unsigned integer in network byte
* order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
* with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
* the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
* 2], and so on.
*
* Required invariants:
* dst_ofs + n_bits <= dst_len * 8
* n_bits <= 64
*/
void
bitwise_put(uint64_t value,
void *dst, unsigned int dst_len, unsigned int dst_ofs,
unsigned int n_bits)
{
ovs_be64 n_value = htonll(value);
bitwise_copy(&n_value, sizeof n_value, 0,
dst, dst_len, dst_ofs,
n_bits);
}
/* Returns the value of the 'n_bits' bits starting at bit 'src_ofs' in 'src',
* which is 'src_len' bytes long.
*
* If you consider all of 'src' to be a single unsigned integer in network byte
* order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
* with value 1 in src[src_len - 1], bit 1 is the bit with value 2, bit 2 is
* the bit with value 4, ..., bit 8 is the bit with value 1 in src[src_len -
* 2], and so on.
*
* Required invariants:
* src_ofs + n_bits <= src_len * 8
* n_bits <= 64
*/
uint64_t
bitwise_get(const void *src, unsigned int src_len,
unsigned int src_ofs, unsigned int n_bits)
{
ovs_be64 value = htonll(0);
bitwise_copy(src, src_len, src_ofs,
&value, sizeof value, 0,
n_bits);
return ntohll(value);
}
/* Returns the value of the bit with offset 'ofs' in 'src', which is 'len'
* bytes long.
*
* If you consider all of 'src' to be a single unsigned integer in network byte
* order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
* with value 1 in src[len - 1], bit 1 is the bit with value 2, bit 2 is the
* bit with value 4, ..., bit 8 is the bit with value 1 in src[len - 2], and so
* on.
*
* Required invariants:
* ofs < len * 8
*/
bool
bitwise_get_bit(const void *src_, unsigned int len, unsigned int ofs)
{
const uint8_t *src = src_;
return (src[len - (ofs / 8 + 1)] & (1u << (ofs % 8))) != 0;
}
/* Sets the bit with offset 'ofs' in 'dst', which is 'len' bytes long, to 0.
*
* If you consider all of 'dst' to be a single unsigned integer in network byte
* order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
* with value 1 in dst[len - 1], bit 1 is the bit with value 2, bit 2 is the
* bit with value 4, ..., bit 8 is the bit with value 1 in dst[len - 2], and so
* on.
*
* Required invariants:
* ofs < len * 8
*/
void
bitwise_put0(void *dst_, unsigned int len, unsigned int ofs)
{
uint8_t *dst = dst_;
dst[len - (ofs / 8 + 1)] &= ~(1u << (ofs % 8));
}
/* Sets the bit with offset 'ofs' in 'dst', which is 'len' bytes long, to 1.
*
* If you consider all of 'dst' to be a single unsigned integer in network byte
* order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
* with value 1 in dst[len - 1], bit 1 is the bit with value 2, bit 2 is the
* bit with value 4, ..., bit 8 is the bit with value 1 in dst[len - 2], and so
* on.
*
* Required invariants:
* ofs < len * 8
*/
void
bitwise_put1(void *dst_, unsigned int len, unsigned int ofs)
{
uint8_t *dst = dst_;
dst[len - (ofs / 8 + 1)] |= 1u << (ofs % 8);
}
/* Sets the bit with offset 'ofs' in 'dst', which is 'len' bytes long, to 'b'.
*
* If you consider all of 'dst' to be a single unsigned integer in network byte
* order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
* with value 1 in dst[len - 1], bit 1 is the bit with value 2, bit 2 is the
* bit with value 4, ..., bit 8 is the bit with value 1 in dst[len - 2], and so
* on.
*
* Required invariants:
* ofs < len * 8
*/
void
bitwise_put_bit(void *dst, unsigned int len, unsigned int ofs, bool b)
{
if (b) {
bitwise_put1(dst, len, ofs);
} else {
bitwise_put0(dst, len, ofs);
}
}
/* Flips the bit with offset 'ofs' in 'dst', which is 'len' bytes long.
*
* If you consider all of 'dst' to be a single unsigned integer in network byte
* order, then bit N is the bit with value 2**N. That is, bit 0 is the bit
* with value 1 in dst[len - 1], bit 1 is the bit with value 2, bit 2 is the
* bit with value 4, ..., bit 8 is the bit with value 1 in dst[len - 2], and so
* on.
*
* Required invariants:
* ofs < len * 8
*/
void
bitwise_toggle_bit(void *dst_, unsigned int len, unsigned int ofs)
{
uint8_t *dst = dst_;
dst[len - (ofs / 8 + 1)] ^= 1u << (ofs % 8);
}
/* ovs_scan */
struct scan_spec {
unsigned int width;
enum {
SCAN_DISCARD,
SCAN_CHAR,
SCAN_SHORT,
SCAN_INT,
SCAN_LONG,
SCAN_LLONG,
SCAN_INTMAX_T,
SCAN_PTRDIFF_T,
SCAN_SIZE_T
} type;
};
static const char *
skip_spaces(const char *s)
{
while (isspace((unsigned char) *s)) {
s++;
}
return s;
}
static const char *
scan_int(const char *s, const struct scan_spec *spec, int base, va_list *args)
{
const char *start = s;
uintmax_t value;
bool negative;
int n_digits;
negative = *s == '-';
s += *s == '-' || *s == '+';
if ((!base || base == 16) && *s == '0' && (s[1] == 'x' || s[1] == 'X')) {
base = 16;
s += 2;
} else if (!base) {
base = *s == '0' ? 8 : 10;
}
if (s - start >= spec->width) {
return NULL;
}
value = 0;
n_digits = 0;
while (s - start < spec->width) {
int digit = hexit_value(*s);
if (digit < 0 || digit >= base) {
break;
}
value = value * base + digit;
n_digits++;
s++;
}
if (!n_digits) {
return NULL;
}
if (negative) {
value = -value;
}
switch (spec->type) {
case SCAN_DISCARD:
break;
case SCAN_CHAR:
*va_arg(*args, char *) = value;
break;
case SCAN_SHORT:
*va_arg(*args, short int *) = value;
break;
case SCAN_INT:
*va_arg(*args, int *) = value;
break;
case SCAN_LONG:
*va_arg(*args, long int *) = value;
break;
case SCAN_LLONG:
*va_arg(*args, long long int *) = value;
break;
case SCAN_INTMAX_T:
*va_arg(*args, intmax_t *) = value;
break;
case SCAN_PTRDIFF_T:
*va_arg(*args, ptrdiff_t *) = value;
break;
case SCAN_SIZE_T:
*va_arg(*args, size_t *) = value;
break;
}
return s;
}
static const char *
skip_digits(const char *s)
{
while (*s >= '0' && *s <= '9') {
s++;
}
return s;
}
static const char *
scan_float(const char *s, const struct scan_spec *spec, va_list *args)
{
const char *start = s;
long double value;
char *tail;
char *copy;
bool ok;
s += *s == '+' || *s == '-';
s = skip_digits(s);
if (*s == '.') {
s = skip_digits(s + 1);
}
if (*s == 'e' || *s == 'E') {
s++;
s += *s == '+' || *s == '-';
s = skip_digits(s);
}
if (s - start > spec->width) {
s = start + spec->width;
}
copy = xmemdup0(start, s - start);
value = strtold(copy, &tail);
ok = *tail == '\0';
free(copy);
if (!ok) {
return NULL;
}
switch (spec->type) {
case SCAN_DISCARD:
break;
case SCAN_INT:
*va_arg(*args, float *) = value;
break;
case SCAN_LONG:
*va_arg(*args, double *) = value;
break;
case SCAN_LLONG:
*va_arg(*args, long double *) = value;
break;
case SCAN_CHAR:
case SCAN_SHORT:
case SCAN_INTMAX_T:
case SCAN_PTRDIFF_T:
case SCAN_SIZE_T:
OVS_NOT_REACHED();
}
return s;
}
static void
scan_output_string(const struct scan_spec *spec,
const char *s, size_t n,
va_list *args)
{
if (spec->type != SCAN_DISCARD) {
char *out = va_arg(*args, char *);
memcpy(out, s, n);
out[n] = '\0';
}
}
static const char *
scan_string(const char *s, const struct scan_spec *spec, va_list *args)
{
size_t n;
for (n = 0; n < spec->width; n++) {
if (!s[n] || isspace((unsigned char) s[n])) {
break;
}
}
if (!n) {
return NULL;
}
scan_output_string(spec, s, n, args);
return s + n;
}
static const char *
parse_scanset(const char *p_, unsigned long *set, bool *complemented)
{
const uint8_t *p = (const uint8_t *) p_;
*complemented = *p == '^';
p += *complemented;
if (*p == ']') {
bitmap_set1(set, ']');
p++;
}
while (*p && *p != ']') {
if (p[1] == '-' && p[2] != ']' && p[2] > *p) {
bitmap_set_multiple(set, *p, p[2] - *p + 1, true);
p += 3;
} else {
bitmap_set1(set, *p++);
}
}
if (*p == ']') {
p++;
}
return (const char *) p;
}
static const char *
scan_set(const char *s, const struct scan_spec *spec, const char **pp,
va_list *args)
{
unsigned long set[BITMAP_N_LONGS(UCHAR_MAX + 1)];
bool complemented;
unsigned int n;
/* Parse the scan set. */
memset(set, 0, sizeof set);
*pp = parse_scanset(*pp, set, &complemented);
/* Parse the data. */
n = 0;
while (s[n]
&& bitmap_is_set(set, (unsigned char) s[n]) == !complemented
&& n < spec->width) {
n++;
}
if (!n) {
return NULL;
}
scan_output_string(spec, s, n, args);
return s + n;
}
static const char *
scan_chars(const char *s, const struct scan_spec *spec, va_list *args)
{
unsigned int n = spec->width == UINT_MAX ? 1 : spec->width;
if (strlen(s) < n) {
return NULL;
}
if (spec->type != SCAN_DISCARD) {
memcpy(va_arg(*args, char *), s, n);
}
return s + n;
}
static bool
ovs_scan__(const char *s, int *n, const char *format, va_list *args)
{
const char *const start = s;
bool ok = false;
const char *p;
p = format;
while (*p != '\0') {
struct scan_spec spec;
unsigned char c = *p++;
bool discard;
if (isspace(c)) {
s = skip_spaces(s);
continue;
} else if (c != '%') {
if (*s != c) {
goto exit;
}
s++;
continue;
} else if (*p == '%') {
if (*s++ != '%') {
goto exit;
}
p++;
continue;
}
/* Parse '*' flag. */
discard = *p == '*';
p += discard;
/* Parse field width. */
spec.width = 0;
while (*p >= '0' && *p <= '9') {
spec.width = spec.width * 10 + (*p++ - '0');
}
if (spec.width == 0) {
spec.width = UINT_MAX;
}
/* Parse type modifier. */
switch (*p) {
case 'h':
if (p[1] == 'h') {
spec.type = SCAN_CHAR;
p += 2;
} else {
spec.type = SCAN_SHORT;
p++;
}
break;
case 'j':
spec.type = SCAN_INTMAX_T;
p++;
break;
case 'l':
if (p[1] == 'l') {
spec.type = SCAN_LLONG;
p += 2;
} else {
spec.type = SCAN_LONG;
p++;
}
break;
case 'L':
case 'q':
spec.type = SCAN_LLONG;
p++;
break;
case 't':
spec.type = SCAN_PTRDIFF_T;
p++;
break;
case 'z':
spec.type = SCAN_SIZE_T;
p++;
break;
default:
spec.type = SCAN_INT;
break;
}
if (discard) {
spec.type = SCAN_DISCARD;
}
c = *p++;
if (c != 'c' && c != 'n' && c != '[') {
s = skip_spaces(s);
}
switch (c) {
case 'd':
s = scan_int(s, &spec, 10, args);
break;
case 'i':
s = scan_int(s, &spec, 0, args);
break;
case 'o':
s = scan_int(s, &spec, 8, args);
break;
case 'u':
s = scan_int(s, &spec, 10, args);
break;
case 'x':
case 'X':
s = scan_int(s, &spec, 16, args);
break;
case 'e':
case 'f':
case 'g':
case 'E':
case 'G':
s = scan_float(s, &spec, args);
break;
case 's':
s = scan_string(s, &spec, args);
break;
case '[':
s = scan_set(s, &spec, &p, args);
break;
case 'c':
s = scan_chars(s, &spec, args);
break;
case 'n':
if (spec.type != SCAN_DISCARD) {
*va_arg(*args, int *) = s - start;
}
break;
}
if (!s) {
goto exit;
}
}
if (n) {
*n = s - start;
}
ok = true;
exit:
return ok;
}
/* This is an implementation of the standard sscanf() function, with the
* following exceptions:
*
* - It returns true if the entire format was successfully scanned and
* converted, false if any conversion failed.
*
* - The standard doesn't define sscanf() behavior when an out-of-range value
* is scanned, e.g. if a "%"PRIi8 conversion scans "-1" or "0x1ff". Some
* implementations consider this an error and stop scanning. This
* implementation never considers an out-of-range value an error; instead,
* it stores the least-significant bits of the converted value in the
* destination, e.g. the value 255 for both examples earlier.
*
* - Only single-byte characters are supported, that is, the 'l' modifier
* on %s, %[, and %c is not supported. The GNU extension 'a' modifier is
* also not supported.
*
* - %p is not supported.
*/
bool
ovs_scan(const char *s, const char *format, ...)
{
va_list args;
bool res;
va_start(args, format);
res = ovs_scan__(s, NULL, format, &args);
va_end(args);
return res;
}
/*
* This function is similar to ovs_scan(), with an extra parameter `n` added to
* return the number of scanned characters.
*/
bool
ovs_scan_len(const char *s, int *n, const char *format, ...)
{
va_list args;
bool success;
int n1;
va_start(args, format);
success = ovs_scan__(s + *n, &n1, format, &args);
va_end(args);
if (success) {
*n = *n + n1;
}
return success;
}
void
xsleep(unsigned int seconds)
{
ovsrcu_quiesce_start();
#ifdef _WIN32
Sleep(seconds * 1000);
#else
sleep(seconds);
#endif
ovsrcu_quiesce_end();
}
static void
xnanosleep__(uint64_t nanoseconds)
{
#ifndef _WIN32
int retval;
struct timespec ts_sleep;
nsec_to_timespec(nanoseconds, &ts_sleep);
int error = 0;
do {
retval = nanosleep(&ts_sleep, NULL);
error = retval < 0 ? errno : 0;
} while (error == EINTR);
#else
HANDLE timer = CreateWaitableTimer(NULL, FALSE, NULL);
if (timer) {
LARGE_INTEGER duetime;
duetime.QuadPart = -nanoseconds;
if (SetWaitableTimer(timer, &duetime, 0, NULL, NULL, FALSE)) {
WaitForSingleObject(timer, INFINITE);
} else {
VLOG_ERR_ONCE("SetWaitableTimer Failed (%s)",
ovs_lasterror_to_string());
}
CloseHandle(timer);
} else {
VLOG_ERR_ONCE("CreateWaitableTimer Failed (%s)",
ovs_lasterror_to_string());
}
#endif
}
/* High resolution sleep with thread quiesce. */
void
xnanosleep(uint64_t nanoseconds)
{
ovsrcu_quiesce_start();
xnanosleep__(nanoseconds);
ovsrcu_quiesce_end();
}
/* High resolution sleep without thread quiesce. */
void
xnanosleep_no_quiesce(uint64_t nanoseconds)
{
xnanosleep__(nanoseconds);
}
#if __linux__
void
set_timer_resolution(unsigned long nanoseconds)
{
prctl(PR_SET_TIMERSLACK, nanoseconds);
}
#else
void
set_timer_resolution(unsigned long nanoseconds OVS_UNUSED)
{
}
#endif
/* Determine whether standard output is a tty or not. This is useful to decide
* whether to use color output or not when --color option for utilities is set
* to `auto`.
*/
bool
is_stdout_a_tty(void)
{
char const *t = getenv("TERM");
return (isatty(STDOUT_FILENO) && t && strcmp(t, "dumb") != 0);
}
#ifdef _WIN32
char *
ovs_format_message(int error)
{
enum { BUFSIZE = sizeof strerror_buffer_get()->s };
char *buffer = strerror_buffer_get()->s;
if (error == 0) {
/* See ovs_strerror */
return "Success";
}
FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
NULL, error, 0, buffer, BUFSIZE, NULL);
return buffer;
}
/* Returns a null-terminated string that explains the last error.
* Use this function to get the error string for WINAPI calls. */
char *
ovs_lasterror_to_string(void)
{
return ovs_format_message(GetLastError());
}
int
ftruncate(int fd, off_t length)
{
int error;
error = _chsize_s(fd, length);
if (error) {
return -1;
}
return 0;
}
OVS_CONSTRUCTOR(winsock_start) {
WSADATA wsaData;
int error;
error = WSAStartup(MAKEWORD(2, 2), &wsaData);
if (error != 0) {
VLOG_FATAL("WSAStartup failed: %s", sock_strerror(sock_errno()));
}
}
#endif
#ifdef __linux__
bool
ovs_kernel_is_version_or_newer(int target_major, int target_minor)
{
static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
static int current_major, current_minor = -1;
if (ovsthread_once_start(&once)) {
struct utsname utsname;
if (uname(&utsname) == -1) {
VLOG_WARN("uname failed (%s)", ovs_strerror(errno));
} else if (!ovs_scan(utsname.release, "%d.%d",
&current_major, &current_minor)) {
VLOG_WARN("uname reported bad OS release (%s)", utsname.release);
}
ovsthread_once_done(&once);
}
if (current_major == -1 || current_minor == -1) {
return false;
}
return current_major > target_major || (
current_major == target_major && current_minor >= target_minor);
}
#endif
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