[libvirt] [PATCHv2] qemu: use virAsprintf instead of PATH_MAX
Eric Blake
eblake at redhat.com
Wed Dec 8 21:57:51 UTC 2010
* src/qemu/qemu_driver.c (qemudLogFD, qemudLogReadFD)
(qemudStartup, qemudGetProcessInfo): Use heap instead of stack.
(qemudDomainDetachPciDiskDevice)
(qemudDomainDetachSCSIDiskDevice): Minor optimization.
---
v2: rebased on top of Ryan's v5 patch
src/qemu/qemu_driver.c | 62 ++++++++++++++++++++++++-----------------------
1 files changed, 32 insertions(+), 30 deletions(-)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 4e65f3b..997d333 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -744,13 +744,11 @@ static int qemuCgroupControllerActive(struct qemud_driver *driver,
static int
qemudLogFD(struct qemud_driver *driver, const char* name, bool append)
{
- char logfile[PATH_MAX];
+ char *logfile;
mode_t logmode;
- int ret, fd = -1;
+ int fd = -1;
- if ((ret = snprintf(logfile, sizeof(logfile), "%s/%s.log",
- driver->logDir, name))
- < 0 || ret >= sizeof(logfile)) {
+ if (virAsprintf(&logfile, "%s/%s.log", driver->logDir, name) < 0) {
virReportOOMError();
return -1;
}
@@ -766,8 +764,10 @@ qemudLogFD(struct qemud_driver *driver, const char* name, bool append)
virReportSystemError(errno,
_("failed to create logfile %s"),
logfile);
+ VIR_FREE(logfile);
return -1;
}
+ VIR_FREE(logfile);
if (virSetCloseExec(fd) < 0) {
virReportSystemError(errno, "%s",
_("Unable to set VM logfile close-on-exec flag"));
@@ -781,30 +781,28 @@ qemudLogFD(struct qemud_driver *driver, const char* name, bool append)
static int
qemudLogReadFD(const char* logDir, const char* name, off_t pos)
{
- char logfile[PATH_MAX];
+ char *logfile;
mode_t logmode = O_RDONLY;
- int ret, fd = -1;
+ int fd = -1;
- if ((ret = snprintf(logfile, sizeof(logfile), "%s/%s.log", logDir, name))
- < 0 || ret >= sizeof(logfile)) {
+ if (virAsprintf(&logfile, "%s/%s.log", logDir, name) < 0) {
qemuReportError(VIR_ERR_INTERNAL_ERROR,
_("failed to build logfile name %s/%s.log"),
logDir, name);
return -1;
}
-
if ((fd = open(logfile, logmode)) < 0) {
virReportSystemError(errno,
_("failed to create logfile %s"),
logfile);
- return -1;
+ goto cleanup;
}
if (virSetCloseExec(fd) < 0) {
virReportSystemError(errno, "%s",
_("Unable to set VM logfile close-on-exec flag"));
VIR_FORCE_CLOSE(fd);
- return -1;
+ goto cleanup;
}
if (pos < 0 || lseek(fd, pos, SEEK_SET) < 0) {
virReportSystemError(pos < 0 ? 0 : errno,
@@ -812,6 +810,9 @@ qemudLogReadFD(const char* logDir, const char* name, off_t pos)
(long long) pos, logfile);
VIR_FORCE_CLOSE(fd);
}
+
+cleanup:
+ VIR_FREE(logfile);
return fd;
}
@@ -1721,7 +1722,7 @@ cleanup:
static int
qemudStartup(int privileged) {
char *base = NULL;
- char driverConf[PATH_MAX];
+ char *driverConf = NULL;
int rc;
virConnectPtr conn = NULL;
@@ -1850,14 +1851,9 @@ qemudStartup(int privileged) {
/* Configuration paths are either ~/.libvirt/qemu/... (session) or
* /etc/libvirt/qemu/... (system).
*/
- if (snprintf (driverConf, sizeof(driverConf), "%s/qemu.conf", base) == -1)
- goto out_of_memory;
- driverConf[sizeof(driverConf)-1] = '\0';
-
- if (virAsprintf(&qemu_driver->configDir, "%s/qemu", base) == -1)
- goto out_of_memory;
-
- if (virAsprintf(&qemu_driver->autostartDir, "%s/qemu/autostart", base) == -1)
+ if (virAsprintf(&driverConf, "%s/qemu.conf", base) < 0 ||
+ virAsprintf(&qemu_driver->configDir, "%s/qemu", base) < 0 ||
+ virAsprintf(&qemu_driver->autostartDir, "%s/qemu/autostart", base) < 0)
goto out_of_memory;
VIR_FREE(base);
@@ -1872,6 +1868,7 @@ qemudStartup(int privileged) {
if (qemudLoadDriverConfig(qemu_driver, driverConf) < 0) {
goto error;
}
+ VIR_FREE(driverConf);
if (qemudSecurityInit(qemu_driver) < 0)
goto error;
@@ -1984,6 +1981,7 @@ error:
if (conn)
virConnectClose(conn);
VIR_FREE(base);
+ VIR_FREE(driverConf);
qemudShutdown();
return -1;
}
@@ -4552,18 +4550,20 @@ cleanup:
}
-static int qemudGetProcessInfo(unsigned long long *cpuTime, int *lastCpu, int pid, int tid) {
- char proc[PATH_MAX];
+static int
+qemudGetProcessInfo(unsigned long long *cpuTime, int *lastCpu, int pid,
+ int tid) {
+ char *proc;
FILE *pidinfo;
unsigned long long usertime, systime;
int cpu;
int ret;
if (tid)
- ret = snprintf(proc, sizeof(proc), "/proc/%d/task/%d/stat", pid, tid);
+ ret = virAsprintf(&proc, "/proc/%d/task/%d/stat", pid, tid);
else
- ret = snprintf(proc, sizeof(proc), "/proc/%d/stat", pid);
- if (ret >= (int)sizeof(proc)) {
+ ret = virAsprintf(&proc, "/proc/%d/stat", pid);
+ if (ret < 0) {
errno = E2BIG;
return -1;
}
@@ -4574,8 +4574,10 @@ static int qemudGetProcessInfo(unsigned long long *cpuTime, int *lastCpu, int pi
*cpuTime = 0;
if (lastCpu)
*lastCpu = 0;
+ VIR_FREE(proc);
return 0;
}
+ VIR_FREE(proc);
/* See 'man proc' for information about what all these fields are. We're
* only interested in a very few of them */
@@ -9063,8 +9065,8 @@ static int qemudDomainDetachPciDiskDevice(struct qemud_driver *driver,
/* build the actual drive id string as the disk->info.alias doesn't
* contain the QEMU_DRIVE_HOST_PREFIX that is passed to qemu */
- if (virAsprintf(&drivestr, "%s%s",
- QEMU_DRIVE_HOST_PREFIX, detach->info.alias) < 0) {
+ if (virAsprintf(&drivestr, QEMU_DRIVE_HOST_PREFIX "%s",
+ detach->info.alias) < 0) {
virReportOOMError();
goto cleanup;
}
@@ -9155,8 +9157,8 @@ static int qemudDomainDetachSCSIDiskDevice(struct qemud_driver *driver,
/* build the actual drive id string as the disk->info.alias doesn't
* contain the QEMU_DRIVE_HOST_PREFIX that is passed to qemu */
- if (virAsprintf(&drivestr, "%s%s",
- QEMU_DRIVE_HOST_PREFIX, detach->info.alias) < 0) {
+ if (virAsprintf(&drivestr, QEMU_DRIVE_HOST_PREFIX "%s",
+ detach->info.alias) < 0) {
virReportOOMError();
goto cleanup;
}
--
1.7.3.2
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