From: "Daniel P. Berrange" <berrange@xxxxxxxxxx>
The logging APIs need to be able to generate formatted timestamps
using only async signal safe functions. This rules out using
gmtime/localtime/malloc/gettimeday(!) and much more.
Introduce a new internal API which is async signal safe.
virTimeMillisNow - replacement for gettimeofday. Uses clock_gettime
where available, otherwise falls back to the unsafe
gettimeofday
virTimeFieldsNow - replacements for gmtime(), convert a timestamp
virTimeFieldsThen into a broken out set of fields. No localtime()
replacement is provided, because converting to
local time is not practical with only async signal
safe APIs.
virTimeStringNow - replacements for strftime() which print a timestamp
virTimeStringThen into a string, using a pre-determined format, with
a fixed size buffer (VIR_TIME_STRING_BUFLEN)
virTimeStringNewNow - alternative to above which malloc a string. Not
virTimeStringNewThen to be used in async signal safe scenarios.
* src/Makefile.am, src/util/virtime.c, src/util/virtime.h: New files
* src/libvirt_private.syms: New APis
* configure.ac: Check for clock_gettime in -lrt
* tests/virtimetest.c, tests/Makefile.am: Test new APIs
---
configure.ac | 10 ++
src/Makefile.am | 7 +-
src/libvirt_private.syms | 11 ++
src/util/virtime.c | 290 ++++++++++++++++++++++++++++++++++++++++++++++
src/util/virtime.h | 50 ++++++++
tests/.gitignore | 1 +
tests/Makefile.am | 9 ++-
tests/virtimetest.c | 124 ++++++++++++++++++++
8 files changed, 499 insertions(+), 3 deletions(-)
create mode 100644 src/util/virtime.c
create mode 100644 src/util/virtime.h
create mode 100644 tests/virtimetest.c
diff --git a/configure.ac b/configure.ac
index e03e401..de2f379 100644
--- a/configure.ac
+++ b/configure.ac
@@ -147,6 +147,16 @@ LIBS="$LIBS $LIB_PTHREAD $LIBMULTITHREAD"
AC_CHECK_FUNCS([pthread_mutexattr_init])
LIBS=$old_libs
+old_LIBS=$LIBS
+RT_LIBS=
+LIBS="$LIBS $LIB_PTHREAD -lrt"
+AC_CHECK_FUNC([clock_gettime],[
+ AC_DEFINE([HAVE_CLOCK_GETTIME],[],[Defined if clock_gettime() exists in librt.so])
+ RT_LIBS=-lrt
+])
+LIBS=$old_libs
+AC_SUBST(RT_LIBS)
+
dnl Availability of various common headers (non-fatal if missing).
AC_CHECK_HEADERS([pwd.h paths.h regex.h sys/un.h \
sys/poll.h syslog.h mntent.h net/ethernet.h linux/magic.h \
diff --git a/src/Makefile.am b/src/Makefile.am
index 33a32a8..872639f 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -97,7 +97,8 @@ UTIL_SOURCES = \
util/virnetdevtap.h util/virnetdevtap.c \
util/virnetdevveth.h util/virnetdevveth.c \
util/virnetdevvportprofile.h util/virnetdevvportprofile.c \
- util/virsocketaddr.h util/virsocketaddr.c
+ util/virsocketaddr.h util/virsocketaddr.c \
+ util/virtime.h util/virtime.c
EXTRA_DIST += $(srcdir)/util/virkeymaps.h $(srcdir)/util/keymaps.csv \
$(srcdir)/util/virkeycode-mapgen.py
@@ -561,7 +562,8 @@ libvirt_util_la_SOURCES = \
libvirt_util_la_CFLAGS = $(CAPNG_CFLAGS) $(YAJL_CFLAGS) $(LIBNL_CFLAGS) \
$(AM_CFLAGS) $(AUDIT_CFLAGS) $(DEVMAPPER_CFLAGS)
libvirt_util_la_LIBADD = $(CAPNG_LIBS) $(YAJL_LIBS) $(LIBNL_LIBS) \
- $(THREAD_LIBS) $(AUDIT_LIBS) $(DEVMAPPER_LIBS)
+ $(THREAD_LIBS) $(AUDIT_LIBS) $(DEVMAPPER_LIBS) \
+ $(RT_LIBS)
noinst_LTLIBRARIES += libvirt_conf.la
@@ -1500,6 +1502,7 @@ libvirt_lxc_LDFLAGS = $(WARN_CFLAGS) $(AM_LDFLAGS)
libvirt_lxc_LDADD = $(CAPNG_LIBS) $(YAJL_LIBS) \
$(LIBXML_LIBS) $(NUMACTL_LIBS) $(THREAD_LIBS) \
$(LIBNL_LIBS) $(AUDIT_LIBS) $(DEVMAPPER_LIBS) \
+ $(RT_LIBS) \
../gnulib/lib/libgnu.la
if WITH_DTRACE
libvirt_lxc_LDADD += probes.o
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 0b21cdc..c90210d 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -1380,6 +1380,17 @@ virKeycodeSetTypeFromString;
virKeycodeValueFromString;
virKeycodeValueTranslate;
+
+# virtime.h
+virTimeMillisNow;
+virTimeFieldsNow;
+virTimeFieldsThen;
+virTimeStringNow;
+virTimeStringThen;
+virTimeStringNewNow;
+virTimeStringNewThen;
+
+
# xml.h
virXMLParseHelper;
virXMLPropString;
diff --git a/src/util/virtime.c b/src/util/virtime.c
new file mode 100644
index 0000000..c2d907f
--- /dev/null
+++ b/src/util/virtime.c
@@ -0,0 +1,290 @@
+/*
+ * virtime.c: Time handling functions
+ *
+ * Copyright (C) 2006-2011 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Daniel P. Berrange <berrange@xxxxxxxxxx>
+ *
+ * The intent is that this file provides a set of time APIs which
+ * are async signal safe, to allow use in between fork/exec eg by
+ * the logging code.
+ *
+ * The reality is that wsnprintf is technically unsafe. We ought
+ * to roll out our int -> str conversions to avoid this.
+ *
+ * We do *not* use regular libvirt error APIs for most of the code,
+ * since those are not async signal safe, and we dont want logging
+ * APIs generating timestamps to blow away real errors
+ */
+
+#include <config.h>
+
+#include <stdio.h>
+#ifndef HAVE_CLOCK_GETTIME
+#include <sys/time.h>
+#endif
+
+#include "virtime.h"
+#include "util.h"
+#include "memory.h"
+#include "virterror_internal.h"
+
+#define VIR_FROM_THIS VIR_FROM_NONE
+
+/* We prefer clock_gettime if available because that is officially
+ * async signal safe according to POSIX. Many platforms lack it
+ * though, so fallback to gettimeofday everywhere else
+ */
+
+/**
+ * virTimeMillisNow:
+ * @now: filled with current time in milliseconds
+ *
+ * Retrieves the current system time, in milliseconds since the
+ * epoch
+ *
+ * Returns 0 on success, -1 on error with errno set
+ */
+int virTimeMillisNow(unsigned long long *now)
+{
+#ifdef HAVE_CLOCK_GETTIME
+ struct timespec ts;
+
+ if (clock_gettime(CLOCK_REALTIME, &ts) < 0)
+ return -1;
+
+ *now = (ts.tv_sec * 1000ull) + (ts.tv_nsec / (1000ull * 1000ull));
+#else
+ struct timeval tv;
+
+ if (gettimeofday(&tv, NULL) < 0)
+ return -1;
+
+ *now = (tv.tv_sec * 1000ull) + (tv.tv_usec / 1000ull);
+#endif
+
+ return 0;
+}
+
+
+/**
+ * virTimeFieldsNow:
+ * @fields: filled with current time fields
+ *
+ * Retrieves the current time, in broken-down field format.
+ * The time is always in UTC.
+ *
+ * Returns 0 on success, -1 on error
+ */
+int virTimeFieldsNow(struct tm *fields)
+{
+ unsigned long long now;
+
+ if (virTimeMillisNow(&now) < 0)
+ return -1;
+
+ return virTimeFieldsThen(now, fields);
+}
+
+
+#define SECS_PER_HOUR (60 * 60)
+#define SECS_PER_DAY (SECS_PER_HOUR * 24)
+#define DIV(a, b) ((a) / (b) - ((a) % (b) < 0))
+#define LEAPS_THRU_END_OF(y) (DIV (y, 4) - DIV (y, 100) + DIV (y, 400))
+
+const unsigned short int __mon_yday[2][13] = {
+ /* Normal years. */
+ { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
+ /* Leap years. */
+ { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
+};
+
+/**
+ * virTimeFieldsThen:
+ * @when: the time to convert in milliseconds
+ * @fields: filled with time @when fields
+ *
+ * Converts the timestamp @when into broken-down field format.
+ * Time time is always in UTC
+ *
+ * Returns 0 on success, -1 on error
+ */
+int virTimeFieldsThen(unsigned long long when, struct tm *fields)
+{
+ /* This code is taken from GLibC under terms of LGPLv2+ */
+ long int days, rem, y;
+ const unsigned short int *ip;
+ unsigned long long whenSecs = when / 1000ull;
+ unsigned int offset = 0; /* We hardcoded GMT */
+
+ days = whenSecs / SECS_PER_DAY;
+ rem = whenSecs % SECS_PER_DAY;
+ rem += offset;
+ while (rem < 0) {
+ rem += SECS_PER_DAY;
+ --days;
+ }
+ while (rem >= SECS_PER_DAY) {
+ rem -= SECS_PER_DAY;
+ ++days;
+ }
+ fields->tm_hour = rem / SECS_PER_HOUR;
+ rem %= SECS_PER_HOUR;
+ fields->tm_min = rem / 60;
+ fields->tm_sec = rem % 60;
+ /* January 1, 1970 was a Thursday. */
+ fields->tm_wday = (4 + days) % 7;
+ if (fields->tm_wday < 0)
+ fields->tm_wday += 7;
+ y = 1970;
+
+ while (days < 0 || days >= (__isleap (y) ? 366 : 365)) {
+ /* Guess a corrected year, assuming 365 days per year. */
+ long int yg = y + days / 365 - (days % 365 < 0);
+
+ /* Adjust DAYS and Y to match the guessed year. */
+ days -= ((yg - y) * 365
+ + LEAPS_THRU_END_OF (yg - 1)
+ - LEAPS_THRU_END_OF (y - 1));
+ y = yg;
+ }
+ fields->tm_year = y - 1900;
+
+ fields->tm_yday = days;
+ ip = __mon_yday[__isleap(y)];
+ for (y = 11; days < (long int) ip[y]; --y)
+ continue;
+ days -= ip[y];
+ fields->tm_mon = y;
+ fields->tm_mday = days + 1;
+ return 0;
+}
+
+
+/**
+ * virTimeStringNow:
+ * @buf: a buffer at least VIR_TIME_STRING_BUFLEN in length
+ *
+ * Initializes @buf to contain a formatted timestamp
+ * corresponding to the current time.
+ *
+ * Returns 0 on success, -1 on error
+ */
+int virTimeStringNow(char *buf)
+{
+ unsigned long long now;
+
+ if (virTimeMillisNow(&now) < 0)
+ return -1;
+
+ return virTimeStringThen(now, buf);
+}
+
+
+/**
+ * virTimeStringThen:
+ * @when: the time to format in milliseconds
+ * @buf: a buffer at least VIR_TIME_STRING_BUFLEN in length
+ *
+ * Initializes @buf to contain a formatted timestamp
+ * corresponding to the time @when.
+ *
+ * Returns 0 on success, -1 on error
+ */
+int virTimeStringThen(unsigned long long when, char *buf)
+{
+ struct tm fields;
+
+ if (virTimeFieldsThen(when, &fields) < 0)
+ return -1;
+
+ fields.tm_year += 1900;
+ fields.tm_mon += 1;
+
+ if (snprintf(buf, VIR_TIME_STRING_BUFLEN,
+ "%4d-%02d-%02d %02d:%02d:%02d.%03d +0000",
+ fields.tm_year, fields.tm_mon, fields.tm_mday,
+ fields.tm_hour, fields.tm_min, fields.tm_sec,
+ (int) (when % 1000)) >= VIR_TIME_STRING_BUFLEN) {
+ errno = ERANGE;
+ return -1;
+ }
+
+ return 0;
+}
+
+
+/**
+ * virTimeStringNow:
+ *
+ * Creates a string containing a formatted timestamp
+ * corresponding to the current time.
+ *
+ * This function is not async signal safe
+ *
+ * Returns a formatted allocated string, or NULL on error
+ */
+char *virTimeStringNewNow(void)
+{
+ char *ret;
+
+ if (VIR_ALLOC_N(ret, VIR_TIME_STRING_BUFLEN) < 0) {
+ virReportOOMError();
+ return NULL;
+ }
+
+ if (virTimeStringNow(ret) < 0) {
+ virReportSystemError(errno, "%s",
+ _("Unable to format time"));
+ VIR_FREE(ret);
+ return NULL;
+ }
+
+ return ret;
+}
+
+
+/**
+ * virTimeStringThen:
+ * @when: the time to format in milliseconds
+ *
+ * Creates a string containing a formatted timestamp
+ * corresponding to the time @when.
+ *
+ * This function is not async signal safe
+ *
+ * Returns a formatted allocated string, or NULL on error
+ */
+char *virTimeStringNewThen(unsigned long long when)
+{
+ char *ret;
+
+ if (VIR_ALLOC_N(ret, VIR_TIME_STRING_BUFLEN) < 0) {
+ virReportOOMError();
+ return NULL;
+ }
+
+ if (virTimeStringThen(when, ret) < 0) {
+ virReportSystemError(errno, "%s",
+ _("Unable to format time"));
+ VIR_FREE(ret);
+ return NULL;
+ }
+
+ return ret;
+}
+
diff --git a/src/util/virtime.h b/src/util/virtime.h
new file mode 100644
index 0000000..3955ba6
--- /dev/null
+++ b/src/util/virtime.h
@@ -0,0 +1,50 @@
+/*
+ * virtime.h: Time handling functions
+ *
+ * Copyright (C) 2006-2011 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Daniel P. Berrange <berrange@xxxxxxxxxx>
+ */
+
+#ifndef __VIR_TIME_H__
+#define __VIR_TIME_H__
+
+#include <time.h>
+
+/* The format string we intend to use is:
+ *
+ * Yr Mon Day Hour Min Sec Ms TZ
+ * %4d-%02d-%02d %02d:%02d:%02d.%03d +0000
+ *
+ */
+#define VIR_TIME_STRING_BUFLEN \
+ (4 + 1 + 2 + 1 + 2 + 1 + 2 + 1 + 2 + 1 + 2 + 1 + 3 + 1 + 5 + 1)
+/* Yr Mon Day Hour Min Sec Ms TZ NULL */
+
+int virTimeMillisNow(unsigned long long *now);
+
+int virTimeFieldsNow(struct tm *fields);
+int virTimeFieldsThen(unsigned long long when, struct tm *fields);
+
+int virTimeStringNow(char *buf);
+int virTimeStringThen(unsigned long long when, char *buf);
+
+char *virTimeStringNewNow(void);
+char *virTimeStringNewThen(unsigned long long when);
+
+
+#endif
diff --git a/tests/.gitignore b/tests/.gitignore
index 7159c37..027b421 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -36,6 +36,7 @@ virnetmessagetest
virnetsockettest
virnettlscontexttest
virshtest
+virtimetest
vmx2xmltest
xencapstest
xmconfigtest
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 6bff670..f3b0c09 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -96,7 +96,8 @@ check_PROGRAMS = virshtest conftest sockettest \
nodeinfotest qparamtest virbuftest \
commandtest commandhelper seclabeltest \
hashtest virnetmessagetest virnetsockettest ssh \
- utiltest virnettlscontexttest shunloadtest
+ utiltest virnettlscontexttest shunloadtest \
+ virtimetest
check_LTLIBRARIES = libshunload.la
@@ -217,6 +218,7 @@ TESTS = virshtest \
virnetmessagetest \
virnetsockettest \
virnettlscontexttest \
+ virtimetest \
shunloadtest \
utiltest \
$(test_scripts)
@@ -495,6 +497,11 @@ else
EXTRA_DIST += pkix_asn1_tab.c
endif
+virtimetest_SOURCES = \
+ virtimetest.c testutils.h testutils.c
+virtimetest_CFLAGS = -Dabs_builddir="\"$(abs_builddir)\"" $(AM_CFLAGS)
+virtimetest_LDADD = ../src/libvirt-net-rpc.la $(LDADDS)
+
seclabeltest_SOURCES = \
seclabeltest.c
diff --git a/tests/virtimetest.c b/tests/virtimetest.c
new file mode 100644
index 0000000..5d56dd3
--- /dev/null
+++ b/tests/virtimetest.c
@@ -0,0 +1,124 @@
+/*
+ * Copyright (C) 2011 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Daniel P. Berrange <berrange@xxxxxxxxxx>
+ */
+
+#include <config.h>
+
+#include <stdlib.h>
+#include <signal.h>
+
+#include "testutils.h"
+#include "util.h"
+#include "virterror_internal.h"
+#include "memory.h"
+#include "logging.h"
+
+#include "virtime.h"
+
+#define VIR_FROM_THIS VIR_FROM_RPC
+
+struct testTimeFieldsData {
+ unsigned long long when;
+ struct tm fields;
+};
+
+static int testTimeFields(const void *args)
+{
+ const struct testTimeFieldsData *data = args;
+ struct tm actual;
+
+ if (virTimeFieldsThen(data->when, &actual) < 0)
+ return -1;
+
+#define COMPARE(field) \
+ do { \
+ if (data->fields.field != actual.field) { \
+ VIR_DEBUG("Expect " #field " %d got %d", \
+ data->fields.field, actual.field); \
+ return -1; \
+ } \
+ } while (0)
+
+ /* tm_year value 0 is based off epoch 1900 */
+ actual.tm_year += 1900;
+ /* tm_mon is range 0-11, but we want 1-12 */
+ actual.tm_mon += 1;
+
+ COMPARE(tm_year);
+ COMPARE(tm_mon);
+ COMPARE(tm_mday);
+ COMPARE(tm_hour);
+ COMPARE(tm_min);
+ COMPARE(tm_sec);
+
+ return 0;
+}
+
+
+static int
+mymain(void)
+{
+ int ret = 0;
+
+ signal(SIGPIPE, SIG_IGN);
+
+#define TEST_FIELDS(ts, year, mon, day, hour, min, sec) \
+ do { \
+ struct testTimeFieldsData data = { \
+ .when = ts, \
+ .fields = { \
+ .tm_year = year, \
+ .tm_mon = mon, \
+ .tm_mday = day, \
+ .tm_hour = hour, \
+ .tm_min = min, \
+ .tm_sec = sec, \
+ .tm_wday = 0, \
+ .tm_yday = 0, \
+ .tm_isdst = 0, \
+ }, \
+ }; \
+ if (virtTestRun("Test fields " #ts " " #year " ", 1, testTimeFields, &data) < 0) \
+ ret = -1; \
+ } while (0)
+
+ TEST_FIELDS( 0ull, 1970, 1, 1, 0, 0, 0);
+ TEST_FIELDS( 5000ull, 1970, 1, 1, 0, 0, 5);
+ TEST_FIELDS( 3605000ull, 1970, 1, 1, 1, 0, 5);
+ TEST_FIELDS( 86405000ull, 1970, 1, 2, 0, 0, 5);
+ TEST_FIELDS( 31536000000ull, 1971, 1, 1, 0, 0, 0);
+
+ TEST_FIELDS( 30866399000ull, 1970, 12, 24, 5, 59, 59);
+ TEST_FIELDS( 123465599000ull, 1973, 11, 29, 23, 59, 59);
+ TEST_FIELDS( 155001599000ull, 1974, 11, 29, 23, 59, 59);
+
+ TEST_FIELDS( 186537599000ull, 1975, 11, 29, 23, 59, 59);
+ TEST_FIELDS( 344390399000ull, 1980, 11, 29, 23, 59, 59);
+ TEST_FIELDS(1203161493000ull, 2008, 2, 16, 11, 31, 33);
+ TEST_FIELDS(1234567890000ull, 2009, 2, 13, 23, 31, 30);
+
+ TEST_FIELDS(1322524800000ull, 2011, 11, 29, 0, 0, 0);
+ TEST_FIELDS(1322611199000ull, 2011, 11, 29, 23, 59, 59);
+
+ TEST_FIELDS(2147483648000ull, 2038, 1, 19, 3, 14, 8);
+
+ return (ret==0 ? EXIT_SUCCESS : EXIT_FAILURE);
+}
+
+VIRT_TEST_MAIN(mymain)
--
1.7.6.4
--
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