Re: [libvirt] [PATCH v2] log: include hostname in initial log message

On the very first log message we send to any output, we include the libvirt version number and package string. In some bug reports we have been given libvirtd.log files that came from a different host than the corresponding /var/log/libvirt/qemu log files. So extend the initial log message to include the hostname too. eg on first log message we would now see: $ libvirtd 2015-12-04 17:35:36.610+0000: 20917: info : libvirt version: 1.3.0 2015-12-04 17:35:36.610+0000: 20917: info : hostname: dhcp-1-180.lcy.redhat.com 2015-12-04 17:35:36.610+0000: 20917: error : qemuMonitorIO:687 : internal error: End of file from monitor Signed-off-by: Daniel P. Berrange <berrange(a)redhat.com&gt; --- src/libvirt_private.syms | 1 + src/util/virlog.c | 72 ++++++++++++++++++++++++++++++++++++------------ src/util/virutil.c | 34 ++++++++++++++++------- src/util/virutil.h | 1 + 4 files changed, 81 insertions(+), 27 deletions(-) diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index dd085c3..f483c4c 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -2387,6 +2387,7 @@ virGetGroupID; virGetGroupList; virGetGroupName; virGetHostname; +virGetHostnameQuiet; virGetListenFDs; virGetSCSIHostNameByParentaddr; virGetSCSIHostNumber; diff --git a/src/util/virlog.c b/src/util/virlog.c index 627f4cb..7d5a266 100644 --- a/src/util/virlog.c +++ b/src/util/virlog.c @@ -94,7 +94,7 @@ static int virLogNbFilters; * after filtering, multiple output can be used simultaneously */ struct _virLogOutput { - bool logVersion; + bool logInitMessage; void *data; virLogOutputFunc f; virLogCloseFunc c; @@ -402,7 +402,7 @@ virLogDefineOutput(virLogOutputFunc f, goto cleanup; } ret = virLogNbOutputs++; - virLogOutputs[ret].logVersion = true; + virLogOutputs[ret].logInitMessage = true; virLogOutputs[ret].f = f; virLogOutputs[ret].c = c; virLogOutputs[ret].data = data; @@ -452,6 +452,32 @@ virLogVersionString(const char **rawmsg, return virLogFormatString(msg, 0, NULL, VIR_LOG_INFO, VIR_LOG_VERSION_STRING); } +/* Similar to virGetHostname() but avoids use of error + * reporting APIs or logging APIs, to prevent recursion + */ +static int +virLogHostnameString(const char **rawmsg, + char **msg) +{ + char *hostname = virGetHostnameQuiet(); + char *hoststr; + + if (!hostname) + return -1; + + if (virAsprintfQuiet(&hoststr, "hostname: %s", hostname) < 0) { + VIR_FREE(hostname); + return -1; + } + + if (virLogFormatString(msg, 0, NULL, VIR_LOG_INFO, hoststr) < 0) { + VIR_FREE(hoststr); + return -1; + } + *rawmsg = hoststr; + return 0; +} + static void virLogSourceUpdate(virLogSourcePtr source) @@ -533,7 +559,7 @@ virLogVMessage(virLogSourcePtr source, const char *fmt, va_list vargs) { - static bool logVersionStderr = true; + static bool logInitMessageStderr = true; char *str = NULL; char *msg = NULL; char timestamp[VIR_TIME_STRING_BUFLEN]; @@ -583,16 +609,22 @@ virLogVMessage(virLogSourcePtr source, */ for (i = 0; i < virLogNbOutputs; i++) { if (priority >= virLogOutputs[i].priority) { - if (virLogOutputs[i].logVersion) { - const char *rawver; - char *ver = NULL; - if (virLogVersionString(&rawver, &ver) >= 0) + if (virLogOutputs[i].logInitMessage) { + const char *rawinitmsg; + char *initmsg = NULL; + if (virLogVersionString(&rawinitmsg, &initmsg) >= 0) + virLogOutputs[i].f(&virLogSelf, VIR_LOG_INFO, + __FILE__, __LINE__, __func__, + timestamp, NULL, 0, rawinitmsg, initmsg, + virLogOutputs[i].data); + VIR_FREE(initmsg); + if (virLogHostnameString(&rawinitmsg, &initmsg) >= 0) virLogOutputs[i].f(&virLogSelf, VIR_LOG_INFO, __FILE__, __LINE__, __func__, - timestamp, NULL, 0, rawver, ver, + timestamp, NULL, 0, rawinitmsg, initmsg, virLogOutputs[i].data); - VIR_FREE(ver); - virLogOutputs[i].logVersion = false; + VIR_FREE(initmsg); + virLogOutputs[i].logInitMessage = false; } virLogOutputs[i].f(source, priority, filename, linenr, funcname, @@ -601,16 +633,22 @@ virLogVMessage(virLogSourcePtr source, } } if (virLogNbOutputs == 0) { - if (logVersionStderr) { - const char *rawver; - char *ver = NULL; - if (virLogVersionString(&rawver, &ver) >= 0) + if (logInitMessageStderr) { + const char *rawinitmsg; + char *initmsg = NULL; + if (virLogVersionString(&rawinitmsg, &initmsg) >= 0) + virLogOutputToFd(&virLogSelf, VIR_LOG_INFO, + __FILE__, __LINE__, __func__, + timestamp, NULL, 0, rawinitmsg, initmsg, + (void *) STDERR_FILENO); + VIR_FREE(initmsg); + if (virLogHostnameString(&rawinitmsg, &initmsg) >= 0) virLogOutputToFd(&virLogSelf, VIR_LOG_INFO, __FILE__, __LINE__, __func__, - timestamp, NULL, 0, rawver, ver, + timestamp, NULL, 0, rawinitmsg, initmsg, (void *) STDERR_FILENO); - VIR_FREE(ver); - logVersionStderr = false; + VIR_FREE(initmsg); + logInitMessageStderr = false; } virLogOutputToFd(source, priority, filename, linenr, funcname, diff --git a/src/util/virutil.c b/src/util/virutil.c index fe65faf..e83def1 100644 --- a/src/util/virutil.c +++ b/src/util/virutil.c @@ -662,16 +662,17 @@ char *virIndexToDiskName(int idx, const char *prefix) * we got from getaddrinfo(). Return the value from gethostname() * and hope for the best. */ -char *virGetHostname(void) +static char *virGetHostnameImpl(bool quiet)

{ int r; - char hostname[HOST_NAME_MAX+1], *result; + char hostname[HOST_NAME_MAX+1], *result = NULL; struct addrinfo hints, *info; r = gethostname(hostname, sizeof(hostname)); if (r == -1) { - virReportSystemError(errno, - "%s", _("failed to determine host name")); + if (!quiet) + virReportSystemError(errno, + "%s", _("failed to determine host name")); return NULL; } NUL_TERMINATE(hostname); @@ -683,7 +684,7 @@ char *virGetHostname(void) * string as-is; it's up to callers to check whether "localhost" * is allowed. */ - ignore_value(VIR_STRDUP(result, hostname)); + ignore_value(VIR_STRDUP_QUIET(result, hostname)); goto cleanup; } @@ -696,9 +697,10 @@ char *virGetHostname(void) hints.ai_family = AF_UNSPEC; r = getaddrinfo(hostname, NULL, &hints, &info); if (r != 0) { - VIR_WARN("getaddrinfo failed for '%s': %s", - hostname, gai_strerror(r)); - ignore_value(VIR_STRDUP(result, hostname)); + if (!quiet) + VIR_WARN("getaddrinfo failed for '%s': %s", + hostname, gai_strerror(r)); + ignore_value(VIR_STRDUP_QUIET(result, hostname)); goto cleanup; } @@ -711,17 +713,29 @@ char *virGetHostname(void) * localhost. Ignore the canonicalized name and just return the * original hostname */ - ignore_value(VIR_STRDUP(result, hostname)); + ignore_value(VIR_STRDUP_QUIET(result, hostname)); else /* Caller frees this string. */ - ignore_value(VIR_STRDUP(result, info->ai_canonname)); + ignore_value(VIR_STRDUP_QUIET(result, info->ai_canonname)); freeaddrinfo(info); cleanup: + if (!result) { + virReportOOMError(); + } return result; } +char *virGetHostname(void) +{ + return virGetHostnameImpl(false); +} + +char *virGetHostnameQuiet(void) +{ + return virGetHostnameImpl(true); +} char * virGetUserDirectory(void) diff --git a/src/util/virutil.h b/src/util/virutil.h index 02387e0..535807c 100644 --- a/src/util/virutil.h +++ b/src/util/virutil.h @@ -132,6 +132,7 @@ static inline int pthread_sigmask(int how, # endif char *virGetHostname(void); +char *virGetHostnameQuiet(void); char *virGetUserDirectory(void); char *virGetUserDirectoryByUID(uid_t uid);