[libvirt] RFC: Removing use of strerror() in favour of strerror_r()
by Daniel P. Berrange
The man page for 'strerror()' has this to say
The strerror() function returns a string describ-
ing the error code passed in the argument errnum,
possibly using the LC_MESSAGES part of the current
locale to select the appropriate language. This
string must not be modified by the application,
but may be modified by a subsequent call to per-
ror(3) or strerror(). No library function will
modify this string.
ie, strerror is not even remotely safe to use if the application calling
libvirt uses threads, regardless of whether libvirt itself is threaded.
The replacement is strerror_r(), but it is kind of tedious to use as
you can't simply pass its return value straight in as format arg.
While looking at this I also noticed that we're rather inconsistent about
whether we use VIR_ERR_INTERNAL_ERROR or VIR_ERR_SYSTEM_ERROR code for
reporting system errors. So I'm intending to create a convenient function
for reporting system errors that hides the sterrror_r horribleness and
also standardizes on error code VIR_ERR_SYSTEM_ERROR. At the same time
also creating a convenience function for reporting OOM, since we have
wildly inconsistent reporting of that too.
The API contracts for src/virterror_internal.h are intended to be:
void virReportSystemErrorFull(virConnectPtr conn,
int domcode,
int theerrno,
const char *filename,
const char *funcname,
long long linenr,
const char *fmt, ...)
ATTRIBUTE_FORMAT(printf, 7, 8);
void virReportOOMFull(virConnectPtr conn,
int domcode,
const char *filename,
const char *funcname,
long long linenr);
And using a macro to automatically set domcode, filename, funcname
and linenr, since its tedious to make the caller supply all those
#define virReportSystemError(conn, theerrno, fmt,...) \
virReportSystemErrorFull((conn), \
VIR_FROM_THIS, \
(theerrno), \
__FILE__, __FUNCTION__, __LINE__, \
(fmt), __VA_ARGS__)
#define virReportOOM(conn) \
virReportOOMFull((conn), VIR_FROM_THIS, \
__FILE__, __FUNCTION__, __LINE__) \
So whereas before you might do
xenXMError (conn, VIR_ERR_INTERNAL_ERROR,
_("cannot stat %s: %s"),
filename, strerror(errno));
xenXMError (conn, VIR_ERR_NO_MEMORY, "%s", strerror(errno));
Now you would do:
virReportSystemError(conn, errno,
_("cannot stat: %s"),
filename);
virReportOOM(conn);
Before I actually go and start making this change across all 300 uses
of strerror(), do people agree with this approach....
Daniel
--
|: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :|
|: http://libvirt.org -o- http://virt-manager.org -o- http://ovirt.org :|
|: http://autobuild.org -o- http://search.cpan.org/~danberr/ :|
|: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|
15 years, 12 months
[libvirt] [PATCH] implement --version for libvirtd
by Dave Allan
The daemon-conf script, when run in verbose mode, tries to execute
libvirtd --version. The attached patch implements --version.
Dave
diff --git a/qemud/qemud.c b/qemud/qemud.c
index f35d0fd..b10d680 100644
--- a/qemud/qemud.c
+++ b/qemud/qemud.c
@@ -2272,6 +2272,13 @@ remoteReadConfigFile (struct qemud_server *server, const char *filename)
return -1;
}
+/* Display version information. */
+static void
+version (const char *argv0)
+{
+ printf ("%s (%s) %s\n", argv0, PACKAGE_NAME, PACKAGE_VERSION);
+}
+
/* Print command-line usage. */
static void
usage (const char *argv0)
@@ -2287,6 +2294,7 @@ Options:\n\
-l | --listen Listen for TCP/IP connections.\n\
-t | --timeout <secs> Exit after timeout period.\n\
-f | --config <file> Configuration file.\n\
+ | --version Display version information.\n\
-p | --pid-file <file> Change name of PID file.\n\
\n\
libvirt management daemon:\n\
@@ -2317,6 +2325,10 @@ libvirt management daemon:\n\
: "(disabled in ./configure)");
}
+enum {
+ OPT_VERSION = 129
+};
+
#define MAX_LISTEN 5
int main(int argc, char **argv) {
struct qemud_server *server = NULL;
@@ -2333,6 +2345,7 @@ int main(int argc, char **argv) {
{ "config", required_argument, NULL, 'f'},
{ "timeout", required_argument, NULL, 't'},
{ "pid-file", required_argument, NULL, 'p'},
+ { "version", no_argument, NULL, OPT_VERSION },
{ "help", no_argument, NULL, '?' },
{0, 0, 0, 0}
};
@@ -2378,6 +2391,10 @@ int main(int argc, char **argv) {
remote_config_file = optarg;
break;
+ case OPT_VERSION:
+ version (argv[0]);
+ return 0;
+
case '?':
usage (argv[0]);
return 2;
15 years, 12 months
[libvirt] [PATCH] retry poll() in EINTR case in virPipeReadUntilEOF
by Dave Allan
I saw a few messages:
libvir: error : internal error poll error: Interrupted system call
during daemon-conf tests. The messages come from virPipeReadUntilEOF.
I think the intention is that this case should be retried. Patch attached.
Dave
diff --git a/src/util.c b/src/util.c
index da26009..31a9702 100644
--- a/src/util.c
+++ b/src/util.c
@@ -473,7 +473,7 @@ virPipeReadUntilEOF(virConnectPtr conn, int outfd, int errfd,
while(!(finished[0] && finished[1])) {
if (poll(fds, ARRAY_CARDINALITY(fds), -1) < 0) {
- if (errno == EAGAIN)
+ if (errno == EAGAIN || errno == EINTR)
continue;
goto pollerr;
}
15 years, 12 months
[libvirt] [PATCH] Sanitize qemu monitor output
by Cole Robinson
The attached patch cleans up output we read from the qemu monitor. This
is a simplified form of a patch I posted awhile ago. From the patch:
/* The monitor doesn't dump clean output after we have written to
* it. Every character we write dumps a bunch of useless stuff,
* so the result looks like "cXcoXcomXcommXcommaXcommanXcommand"
* Try to throw away everything before the first full command
* occurence, and inbetween the command and the newline starting
* the response
*/
This extra output makes our qemu log files _huge_ if doing things like
polling disk/net stats, and prevents us from returning any useful error
message printed from the monitor (say for media/disk eject, disk/net
stats, etc).
I've been running with this patch for a while and haven't hit any issues.
Thanks,
Cole
15 years, 12 months
[libvirt] [PATCH] build: avoid libvirtd link failure with CFLAGS=-g
by Jim Meyering
Building libvirtd with CFLAGS=-g (and not -O) failed:
../src/.libs/libvirt_driver_qemu.a(libvirt_driver_qemu_la-qemu_driver.o): In function `qemudExtractMonitorPath':
/home/meyering/w/co/libvirt/src/qemu_driver.c:549: undefined reference to `c_isspace'
../src/.libs/libvirt_driver_qemu.a(libvirt_driver_qemu_la-qemu_driver.o): In function `qemudDetectVcpuPIDs':
/home/meyering/w/co/libvirt/src/qemu_driver.c:702: undefined reference to `c_isspace'
collect2: ld returned 1 exit status
make[2]: *** [libvirtd] Error 1
make[2]: Leaving directory `/home/meyering/w/co/libvirt/qemud'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/home/meyering/w/co/libvirt'
make: *** [all] Error 2
Here's the fix:
>From 7b963a92060c4591ce5c89f85301c35655056557 Mon Sep 17 00:00:00 2001
From: Jim Meyering <meyering(a)redhat.com>
Date: Thu, 11 Dec 2008 18:43:12 +0100
Subject: [PATCH] build: avoid libvirtd link failure with CFLAGS=-g
* qemud/Makefile.am (libvirtd_LDADD): Add gnulib's libgnu.la last.
Otherwise, building with -g (no inlining) would fail due to a use
of c_isspace in libvirt_driver_qemu.a, which used to followed
libgnu.a in the link command.
---
qemud/Makefile.am | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/qemud/Makefile.am b/qemud/Makefile.am
index 8cb0847..ea89d06 100644
--- a/qemud/Makefile.am
+++ b/qemud/Makefile.am
@@ -93,8 +93,7 @@ libvirtd_LDADD = \
$(LIBXML_LIBS) \
$(GNUTLS_LIBS) \
$(SASL_LIBS) \
- $(POLKIT_LIBS) \
- ../gnulib/lib/libgnu.la
+ $(POLKIT_LIBS)
if ! WITH_DRIVER_MODULES
if WITH_QEMU
@@ -244,6 +243,9 @@ uninstall-init:
endif # DBUS_INIT_SCRIPTS_RED_HAT
+# This must be added last.
+libvirtd_LDADD += ../gnulib/lib/libgnu.la
+
endif # WITH_LIBVIRTD
CLEANFILES = libvirtd.init
--
1.6.0.4.1044.g77718
15 years, 12 months
[libvirt] [PATCH] Fix locking issue in testVolumeLookupByPath
by Cole Robinson
The attached patch fixes a locking issue in the test driver,
specifically testStorageVolumeLookupByPath. We were only unlocking the
pool object if it was running. This fixed a deadlock I was seeing while
adding some new tests to virtinst's test framework.
Thanks,
Cole
15 years, 12 months
[libvirt] [PATCH] Fix 'virsh pool-list' locking issue
by Cole Robinson
Running 'virsh pool-list' seems to deadlock libvirtd. Dan gave me some
debugging tips, and I managed to track it down to the poolGetAutostart
function. The attached patch fixes the issue.
Thanks,
Cole
15 years, 12 months
