[Libvir] PATCH: Pull generic I/O apis out of QEMU driver
Daniel P. Berrange
berrange at redhat.com
Sun Dec 2 18:53:53 UTC 2007
The QEMU driver has a number of handy APIs which I want to use from the
storage driver:
- Read entire file in one go
- Check filename suffix
- Compare filename against name + suffix
- Check link destination
- Construct a filename from dir, name + suffix
- Recursively make a directory
This patch pulls all these methods out of the QEMU driver, gives them a
sensible name and adds them to the util.h file. No functional change, this
is a straight refactoring.
qemu_conf.c | 256 ++++------------------------------------------------------
qemu_conf.h | 1
qemu_driver.c | 6 -
util.c | 223 ++++++++++++++++++++++++++++++++++++++++++++++++++
util.h | 29 ++++++
5 files changed, 275 insertions(+), 240 deletions(-)
diff -r 41c9eb891349 src/qemu_conf.c
--- a/src/qemu_conf.c Sun Dec 02 13:30:44 2007 -0500
+++ b/src/qemu_conf.c Sun Dec 02 13:40:44 2007 -0500
@@ -48,6 +48,7 @@
#include "uuid.h"
#include "buf.h"
#include "conf.h"
+#include "util.h"
#define qemudLog(level, msg...) fprintf(stderr, msg)
@@ -227,55 +228,6 @@ void qemudFreeVM(struct qemud_vm *vm) {
free(vm);
}
-/* Build up a fully qualfiied path for a config file to be
- * associated with a persistent guest or network */
-static int
-qemudMakeConfigPath(const char *configDir,
- const char *name,
- const char *ext,
- char *buf,
- unsigned int buflen) {
- if ((strlen(configDir) + 1 + strlen(name) + (ext ? strlen(ext) : 0) + 1) > buflen)
- return -1;
-
- strcpy(buf, configDir);
- strcat(buf, "/");
- strcat(buf, name);
- if (ext)
- strcat(buf, ext);
- return 0;
-}
-
-int
-qemudEnsureDir(const char *path)
-{
- struct stat st;
- char parent[PATH_MAX];
- char *p;
- int err;
-
- if (stat(path, &st) >= 0)
- return 0;
-
- strncpy(parent, path, PATH_MAX);
- parent[PATH_MAX - 1] = '\0';
-
- if (!(p = strrchr(parent, '/')))
- return EINVAL;
-
- if (p == parent)
- return EPERM;
-
- *p = '\0';
-
- if ((err = qemudEnsureDir(parent)))
- return err;
-
- if (mkdir(path, 0777) < 0 && errno != EEXIST)
- return errno;
-
- return 0;
-}
/* The list of possible machine types for various architectures,
as supported by QEMU - taken from 'qemu -M ?' for each arch */
@@ -2075,22 +2027,22 @@ qemudSaveVMDef(virConnectPtr conn,
if (vm->configFile[0] == '\0') {
int err;
- if ((err = qemudEnsureDir(driver->configDir))) {
+ if ((err = virFileMakePath(driver->configDir))) {
qemudReportError(conn, NULL, NULL, VIR_ERR_INTERNAL_ERROR,
"cannot create config directory %s: %s",
driver->configDir, strerror(err));
return -1;
}
- if (qemudMakeConfigPath(driver->configDir, def->name, ".xml",
- vm->configFile, PATH_MAX) < 0) {
+ if (virFileBuildPath(driver->configDir, def->name, ".xml",
+ vm->configFile, PATH_MAX) < 0) {
qemudReportError(conn, NULL, NULL, VIR_ERR_INTERNAL_ERROR,
"cannot construct config file path");
return -1;
}
- if (qemudMakeConfigPath(driver->autostartDir, def->name, ".xml",
- vm->autostartLink, PATH_MAX) < 0) {
+ if (virFileBuildPath(driver->autostartDir, def->name, ".xml",
+ vm->autostartLink, PATH_MAX) < 0) {
qemudReportError(conn, NULL, NULL, VIR_ERR_INTERNAL_ERROR,
"cannot construct autostart link path");
vm->configFile[0] = '\0';
@@ -2114,7 +2066,7 @@ static int qemudSaveNetworkConfig(virCon
return -1;
}
- if ((err = qemudEnsureDir(driver->networkConfigDir))) {
+ if ((err = virFileMakePath(driver->networkConfigDir))) {
qemudReportError(conn, NULL, NULL, VIR_ERR_INTERNAL_ERROR,
"cannot create config directory %s: %s",
driver->networkConfigDir, strerror(err));
@@ -2521,22 +2473,22 @@ qemudSaveNetworkDef(virConnectPtr conn,
if (network->configFile[0] == '\0') {
int err;
- if ((err = qemudEnsureDir(driver->networkConfigDir))) {
+ if ((err = virFileMakePath(driver->networkConfigDir))) {
qemudReportError(conn, NULL, NULL, VIR_ERR_INTERNAL_ERROR,
"cannot create config directory %s: %s",
driver->networkConfigDir, strerror(err));
return -1;
}
- if (qemudMakeConfigPath(driver->networkConfigDir, def->name, ".xml",
- network->configFile, PATH_MAX) < 0) {
+ if (virFileBuildPath(driver->networkConfigDir, def->name, ".xml",
+ network->configFile, PATH_MAX) < 0) {
qemudReportError(conn, NULL, NULL, VIR_ERR_INTERNAL_ERROR,
"cannot construct config file path");
return -1;
}
- if (qemudMakeConfigPath(driver->networkAutostartDir, def->name, ".xml",
- network->autostartLink, PATH_MAX) < 0) {
+ if (virFileBuildPath(driver->networkAutostartDir, def->name, ".xml",
+ network->autostartLink, PATH_MAX) < 0) {
qemudReportError(conn, NULL, NULL, VIR_ERR_INTERNAL_ERROR,
"cannot construct autostart link path");
network->configFile[0] = '\0';
@@ -2547,174 +2499,6 @@ qemudSaveNetworkDef(virConnectPtr conn,
return qemudSaveNetworkConfig(conn, driver, network, def);
}
-static int
-qemudReadFile(const char *path,
- char *buf,
- int maxlen) {
- FILE *fh;
- struct stat st;
- int ret = 0;
-
- if (!(fh = fopen(path, "r"))) {
- qemudLog(QEMUD_WARN, "Failed to open file '%s': %s",
- path, strerror(errno));
- goto error;
- }
-
- if (fstat(fileno(fh), &st) < 0) {
- qemudLog(QEMUD_WARN, "Failed to stat file '%s': %s",
- path, strerror(errno));
- goto error;
- }
-
- if (S_ISDIR(st.st_mode)) {
- qemudDebug("Ignoring directory '%s' - clearly not a config file", path);
- goto error;
- }
-
- if (st.st_size >= maxlen) {
- qemudLog(QEMUD_WARN, "File '%s' is too large", path);
- goto error;
- }
-
- if ((ret = fread(buf, st.st_size, 1, fh)) != 1) {
- qemudLog(QEMUD_WARN, "Failed to read config file '%s': %s",
- path, strerror(errno));
- goto error;
- }
-
- buf[st.st_size] = '\0';
-
- ret = 1;
-
- error:
- if (fh)
- fclose(fh);
-
- return ret;
-}
-
-static int
-compareFileToNameSuffix(const char *file,
- const char *name,
- const char *suffix) {
- int filelen = strlen(file);
- int namelen = strlen(name);
- int suffixlen = strlen(suffix);
-
- if (filelen == (namelen + suffixlen) &&
- !strncmp(file, name, namelen) &&
- !strncmp(file + namelen, suffix, suffixlen))
- return 1;
- else
- return 0;
-}
-
-static int
-hasSuffix(const char *str,
- const char *suffix)
-{
- int len = strlen(str);
- int suffixlen = strlen(suffix);
-
- if (len < suffixlen)
- return 0;
-
- return strcmp(str + len - suffixlen, suffix) == 0;
-}
-
-static int
-checkLinkPointsTo(const char *checkLink,
- const char *checkDest)
-{
- char dest[PATH_MAX];
- char real[PATH_MAX];
- char checkReal[PATH_MAX];
- int n;
- int passed = 0;
-
- /* read the link destination */
- if ((n = readlink(checkLink, dest, PATH_MAX)) < 0) {
- switch (errno) {
- case ENOENT:
- case ENOTDIR:
- break;
-
- case EINVAL:
- qemudLog(QEMUD_WARN, "Autostart file '%s' is not a symlink",
- checkLink);
- break;
-
- default:
- qemudLog(QEMUD_WARN, "Failed to read autostart symlink '%s': %s",
- checkLink, strerror(errno));
- break;
- }
-
- goto failed;
- } else if (n >= PATH_MAX) {
- qemudLog(QEMUD_WARN, "Symlink '%s' contents too long to fit in buffer",
- checkLink);
- goto failed;
- }
-
- dest[n] = '\0';
-
- /* make absolute */
- if (dest[0] != '/') {
- char dir[PATH_MAX];
- char tmp[PATH_MAX];
- char *p;
-
- strncpy(dir, checkLink, PATH_MAX);
- dir[PATH_MAX-1] = '\0';
-
- if (!(p = strrchr(dir, '/'))) {
- qemudLog(QEMUD_WARN, "Symlink path '%s' is not absolute", checkLink);
- goto failed;
- }
-
- if (p == dir) /* handle unlikely root dir case */
- p++;
-
- *p = '\0';
-
- if (qemudMakeConfigPath(dir, dest, NULL, tmp, PATH_MAX) < 0) {
- qemudLog(QEMUD_WARN, "Path '%s/%s' is too long", dir, dest);
- goto failed;
- }
-
- strncpy(dest, tmp, PATH_MAX);
- dest[PATH_MAX-1] = '\0';
- }
-
- /* canonicalize both paths */
- if (!realpath(dest, real)) {
- qemudLog(QEMUD_WARN, "Failed to expand path '%s' :%s",
- dest, strerror(errno));
- strncpy(real, dest, PATH_MAX);
- real[PATH_MAX-1] = '\0';
- }
-
- if (!realpath(checkDest, checkReal)) {
- qemudLog(QEMUD_WARN, "Failed to expand path '%s' :%s",
- checkDest, strerror(errno));
- strncpy(checkReal, checkDest, PATH_MAX);
- checkReal[PATH_MAX-1] = '\0';
- }
-
- /* compare */
- if (strcmp(checkReal, real) != 0) {
- qemudLog(QEMUD_WARN, "Autostart link '%s' is not a symlink to '%s', ignoring",
- checkLink, checkReal);
- goto failed;
- }
-
- passed = 1;
-
- failed:
- return passed;
-}
static struct qemud_vm *
qemudLoadConfig(struct qemud_driver *driver,
@@ -2732,7 +2516,7 @@ qemudLoadConfig(struct qemud_driver *dri
return NULL;
}
- if (!compareFileToNameSuffix(file, def->name, ".xml")) {
+ if (!virFileMatchesNameSuffix(file, def->name, ".xml")) {
qemudLog(QEMUD_WARN, "QEMU guest config filename '%s' does not match guest name '%s'",
path, def->name);
qemudFreeVMDef(def);
@@ -2751,7 +2535,7 @@ qemudLoadConfig(struct qemud_driver *dri
strncpy(vm->autostartLink, autostartLink, PATH_MAX);
vm->autostartLink[PATH_MAX-1] = '\0';
- vm->autostart = checkLinkPointsTo(vm->autostartLink, vm->configFile);
+ vm->autostart = virFileLinkPointsTo(vm->autostartLink, vm->configFile);
return vm;
}
@@ -2772,7 +2556,7 @@ qemudLoadNetworkConfig(struct qemud_driv
return NULL;
}
- if (!compareFileToNameSuffix(file, def->name, ".xml")) {
+ if (!virFileMatchesNameSuffix(file, def->name, ".xml")) {
qemudLog(QEMUD_WARN, "Network config filename '%s' does not match network name '%s'",
path, def->name);
qemudFreeNetworkDef(def);
@@ -2791,7 +2575,7 @@ qemudLoadNetworkConfig(struct qemud_driv
strncpy(network->autostartLink, autostartLink, PATH_MAX);
network->autostartLink[PATH_MAX-1] = '\0';
- network->autostart = checkLinkPointsTo(network->autostartLink, network->configFile);
+ network->autostart = virFileLinkPointsTo(network->autostartLink, network->configFile);
return network;
}
@@ -2820,22 +2604,22 @@ int qemudScanConfigDir(struct qemud_driv
if (entry->d_name[0] == '.')
continue;
- if (!hasSuffix(entry->d_name, ".xml"))
+ if (!virFileHasSuffix(entry->d_name, ".xml"))
continue;
- if (qemudMakeConfigPath(configDir, entry->d_name, NULL, path, PATH_MAX) < 0) {
+ if (virFileBuildPath(configDir, entry->d_name, NULL, path, PATH_MAX) < 0) {
qemudLog(QEMUD_WARN, "Config filename '%s/%s' is too long",
configDir, entry->d_name);
continue;
}
- if (qemudMakeConfigPath(autostartDir, entry->d_name, NULL, autostartLink, PATH_MAX) < 0) {
+ if (virFileBuildPath(autostartDir, entry->d_name, NULL, autostartLink, PATH_MAX) < 0) {
qemudLog(QEMUD_WARN, "Autostart link path '%s/%s' is too long",
autostartDir, entry->d_name);
continue;
}
- if (!qemudReadFile(path, xml, QEMUD_MAX_XML_LEN))
+ if (virFileReadAll(path, xml, QEMUD_MAX_XML_LEN) < 0)
continue;
if (isGuest)
diff -r 41c9eb891349 src/qemu_conf.h
--- a/src/qemu_conf.h Sun Dec 02 13:30:44 2007 -0500
+++ b/src/qemu_conf.h Sun Dec 02 13:40:44 2007 -0500
@@ -362,7 +362,6 @@ int qemudDeleteConfig
struct qemud_driver *driver,
const char *configFile,
const char *name);
-int qemudEnsureDir (const char *path);
void qemudFreeVMDef (struct qemud_vm_def *vm);
void qemudFreeVM (struct qemud_vm *vm);
diff -r 41c9eb891349 src/qemu_driver.c
--- a/src/qemu_driver.c Sun Dec 02 13:30:44 2007 -0500
+++ b/src/qemu_driver.c Sun Dec 02 13:40:44 2007 -0500
@@ -632,7 +632,7 @@ static int qemudStartVMDaemon(virConnect
strcat(logfile, vm->def->name);
strcat(logfile, ".log");
- if (qemudEnsureDir(driver->logDir) < 0) {
+ if (virFileMakePath(driver->logDir) < 0) {
qemudReportError(conn, NULL, NULL, VIR_ERR_INTERNAL_ERROR,
"cannot create log directory %s: %s",
driver->logDir, strerror(errno));
@@ -2458,7 +2458,7 @@ static int qemudDomainSetAutostart(virDo
if (autostart) {
int err;
- if ((err = qemudEnsureDir(driver->autostartDir))) {
+ if ((err = virFileMakePath(driver->autostartDir))) {
qemudReportError(dom->conn, dom, NULL, VIR_ERR_INTERNAL_ERROR,
"cannot create autostart directory %s: %s",
driver->autostartDir, strerror(err));
@@ -2806,7 +2806,7 @@ static int qemudNetworkSetAutostart(virN
if (autostart) {
int err;
- if ((err = qemudEnsureDir(driver->networkAutostartDir))) {
+ if ((err = virFileMakePath(driver->networkAutostartDir))) {
qemudReportError(net->conn, NULL, net, VIR_ERR_INTERNAL_ERROR,
"cannot create autostart directory %s: %s",
driver->networkAutostartDir, strerror(err));
diff -r 41c9eb891349 src/util.c
--- a/src/util.c Sun Dec 02 13:30:44 2007 -0500
+++ b/src/util.c Sun Dec 02 13:40:44 2007 -0500
@@ -30,12 +30,16 @@
#include <fcntl.h>
#include <paths.h>
#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
#include <libvirt/virterror.h>
#include "event.h"
#include "buf.h"
#include "util.h"
#define MAX_ERROR_LEN 1024
+
+#define virLog(msg...) fprintf(stderr, msg)
static void
ReportError(virConnectPtr conn,
@@ -214,6 +218,7 @@ ssize_t safewrite(int fd, const void *bu
size_t nwritten = 0;
while (count > 0) {
int r = write(fd, buf, count);
+
if (r < 0 && errno == EINTR)
continue;
if (r < 0)
@@ -226,3 +231,221 @@ ssize_t safewrite(int fd, const void *bu
}
return nwritten;
}
+
+
+int virFileReadAll(const char *path,
+ char *buf,
+ unsigned int buflen)
+{
+ FILE *fh;
+ struct stat st;
+ int ret = -1;
+
+ if (!(fh = fopen(path, "r"))) {
+ virLog("Failed to open file '%s': %s",
+ path, strerror(errno));
+ goto error;
+ }
+
+ if (fstat(fileno(fh), &st) < 0) {
+ virLog("Failed to stat file '%s': %s",
+ path, strerror(errno));
+ goto error;
+ }
+
+ if (S_ISDIR(st.st_mode)) {
+ virLog("Ignoring directory '%s'", path);
+ goto error;
+ }
+
+ if (st.st_size >= (buflen-1)) {
+ virLog("File '%s' is too large", path);
+ goto error;
+ }
+
+ if ((ret = fread(buf, st.st_size, 1, fh)) != 1) {
+ virLog("Failed to read config file '%s': %s",
+ path, strerror(errno));
+ goto error;
+ }
+
+ buf[st.st_size] = '\0';
+
+ ret = 0;
+
+ error:
+ if (fh)
+ fclose(fh);
+
+ return ret;
+}
+
+int virFileMatchesNameSuffix(const char *file,
+ const char *name,
+ const char *suffix)
+{
+ int filelen = strlen(file);
+ int namelen = strlen(name);
+ int suffixlen = strlen(suffix);
+
+ if (filelen == (namelen + suffixlen) &&
+ !strncmp(file, name, namelen) &&
+ !strncmp(file + namelen, suffix, suffixlen))
+ return 1;
+ else
+ return 0;
+}
+
+int virFileHasSuffix(const char *str,
+ const char *suffix)
+{
+ int len = strlen(str);
+ int suffixlen = strlen(suffix);
+
+ if (len < suffixlen)
+ return 0;
+
+ return strcmp(str + len - suffixlen, suffix) == 0;
+}
+
+
+int virFileLinkPointsTo(const char *checkLink,
+ const char *checkDest)
+{
+ char dest[PATH_MAX];
+ char real[PATH_MAX];
+ char checkReal[PATH_MAX];
+ int n;
+
+ /* read the link destination */
+ if ((n = readlink(checkLink, dest, PATH_MAX)) < 0) {
+ switch (errno) {
+ case ENOENT:
+ case ENOTDIR:
+ return 0;
+
+ case EINVAL:
+ virLog("File '%s' is not a symlink",
+ checkLink);
+ return 0;
+
+ }
+ virLog("Failed to read symlink '%s': %s",
+ checkLink, strerror(errno));
+ return 0;
+ } else if (n >= PATH_MAX) {
+ virLog("Symlink '%s' contents too long to fit in buffer",
+ checkLink);
+ return 0;
+ }
+
+ dest[n] = '\0';
+
+ /* make absolute */
+ if (dest[0] != '/') {
+ char dir[PATH_MAX];
+ char tmp[PATH_MAX];
+ char *p;
+
+ strncpy(dir, checkLink, PATH_MAX);
+ dir[PATH_MAX-1] = '\0';
+
+ if (!(p = strrchr(dir, '/'))) {
+ virLog("Symlink path '%s' is not absolute", checkLink);
+ return 0;
+ }
+
+ if (p == dir) /* handle unlikely root dir case */
+ p++;
+
+ *p = '\0';
+
+ if (virFileBuildPath(dir, dest, NULL, tmp, PATH_MAX) < 0) {
+ virLog("Path '%s/%s' is too long", dir, dest);
+ return 0;
+ }
+
+ strncpy(dest, tmp, PATH_MAX);
+ dest[PATH_MAX-1] = '\0';
+ }
+
+ /* canonicalize both paths */
+ if (!realpath(dest, real)) {
+ virLog("Failed to expand path '%s' :%s", dest, strerror(errno));
+ strncpy(real, dest, PATH_MAX);
+ real[PATH_MAX-1] = '\0';
+ }
+
+ if (!realpath(checkDest, checkReal)) {
+ virLog("Failed to expand path '%s' :%s", checkDest, strerror(errno));
+ strncpy(checkReal, checkDest, PATH_MAX);
+ checkReal[PATH_MAX-1] = '\0';
+ }
+
+ /* compare */
+ if (strcmp(checkReal, real) != 0) {
+ virLog("Link '%s' does not point to '%s', ignoring",
+ checkLink, checkReal);
+ return 0;
+ }
+
+ return 1;
+}
+
+int virFileMakePath(const char *path)
+{
+ struct stat st;
+ char parent[PATH_MAX];
+ char *p;
+ int err;
+
+ if (stat(path, &st) >= 0)
+ return 0;
+
+ strncpy(parent, path, PATH_MAX);
+ parent[PATH_MAX - 1] = '\0';
+
+ if (!(p = strrchr(parent, '/')))
+ return EINVAL;
+
+ if (p == parent)
+ return EPERM;
+
+ *p = '\0';
+
+ if ((err = virFileMakePath(parent)))
+ return err;
+
+ if (mkdir(path, 0777) < 0 && errno != EEXIST)
+ return errno;
+
+ return 0;
+}
+
+/* Build up a fully qualfiied path for a config file to be
+ * associated with a persistent guest or network */
+int virFileBuildPath(const char *dir,
+ const char *name,
+ const char *ext,
+ char *buf,
+ unsigned int buflen)
+{
+ if ((strlen(dir) + 1 + strlen(name) + (ext ? strlen(ext) : 0) + 1) >= (buflen-1))
+ return -1;
+
+ strcpy(buf, dir);
+ strcat(buf, "/");
+ strcat(buf, name);
+ if (ext)
+ strcat(buf, ext);
+ return 0;
+}
+
+/*
+ * Local variables:
+ * indent-tabs-mode: nil
+ * c-indent-level: 4
+ * c-basic-offset: 4
+ * tab-width: 4
+ * End:
+ */
diff -r 41c9eb891349 src/util.h
--- a/src/util.h Sun Dec 02 13:30:44 2007 -0500
+++ b/src/util.h Sun Dec 02 13:40:44 2007 -0500
@@ -21,8 +21,37 @@
* File created Jul 18, 2007 - Shuveb Hussain <shuveb at binarykarma.com>
*/
+#ifndef __VIR_UTIL_H__
+#define __VIR_UTIL_H__
+
+#include "internal.h"
+
int virExec(virConnectPtr conn, char **argv, int *retpid, int infd, int *outfd, int *errfd);
int virExecNonBlock(virConnectPtr conn, char **argv, int *retpid, int infd, int *outfd, int *errfd);
int saferead(int fd, void *buf, size_t count);
ssize_t safewrite(int fd, const void *buf, size_t count);
+
+int virFileReadAll(const char *path,
+ char *buf,
+ unsigned int buflen);
+
+int virFileMatchesNameSuffix(const char *file,
+ const char *name,
+ const char *suffix);
+
+int virFileHasSuffix(const char *str,
+ const char *suffix);
+
+int virFileLinkPointsTo(const char *checkLink,
+ const char *checkDest);
+int virFileMakePath(const char *path);
+
+int virFileBuildPath(const char *dir,
+ const char *name,
+ const char *ext,
+ char *buf,
+ unsigned int buflen);
+
+
+#endif /* __VIR_UTIL_H__ */
Dan.
--
|=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=|
|=- Perl modules: http://search.cpan.org/~danberr/ -=|
|=- Projects: http://freshmeat.net/~danielpb/ -=|
|=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|
More information about the libvir-list
mailing list