lxc api: fix some config_path oddities

src/lua-lxc/core.c

@@ -44,7 +44,7 @@
 static int container_new(lua_State *L)
 {
     const char *name = luaL_checkstring(L, 1);
-    struct lxc_container *c = lxc_container_new(name);
+    struct lxc_container *c = lxc_container_new(name, NULL);
 
     if (c) {
 	lua_boxpointer(L, c);

src/lxc/lxc.h

@@ -182,7 +182,7 @@ extern const char const *lxc_version(void);
 /*
  * Create and return a new lxccontainer struct.
  */
-extern struct lxc_container *lxc_container_new(const char *name);
+extern struct lxc_container *lxc_container_new(const char *name, const char *configpath);
 
 /*
  * Returns 1 on success, 0 on failure.

src/lxc/lxccontainer.c

@@ -871,10 +871,45 @@ static const char *lxcapi_get_config_path(struct lxc_container *c)
 	return (const char *)(c->config_path);
 }
 
+/*
+ * not for export
+ * Just recalculate the c->configfile based on the
+ * c->config_path, which must be set.
+ * The lxc_container must be locked or not yet public.
+ */
+static bool set_config_filename(struct lxc_container *c)
+{
+	char *newpath;
+	int len, ret;
+
+	if (!c->config_path)
+		return false;
+
+	/* $lxc_path + "/" + c->name + "/" + "config" + '\0' */
+	len = strlen(c->config_path) + strlen(c->name) + strlen("config") + 3;
+	newpath = malloc(len);
+	if (!newpath)
+		return false;
+
+	ret = snprintf(newpath, len, "%s/%s/config", c->config_path, c->name);
+	if (ret < 0 || ret >= len) {
+		fprintf(stderr, "Error printing out config file name\n");
+		free(newpath);
+		return false;
+	}
+
+	if (c->configfile)
+		free(c->configfile);
+	c->configfile = newpath;
+
+	return true;
+}
+
 static bool lxcapi_set_config_path(struct lxc_container *c, const char *path)
 {
 	char *p;
 	bool b = false;
+	char *oldpath = NULL;
 
 	if (!c)
 		return b;
@@ -883,13 +918,28 @@ static bool lxcapi_set_config_path(struct lxc_container *c, const char *path)
 		return b;
 
 	p = strdup(path);
-	if (!p)
+	if (!p) {
+		ERROR("Out of memory setting new lxc path");
 		goto err;
+	}
+
 	b = true;
 	if (c->config_path)
-		free(c->config_path);
+		oldpath = c->config_path;
 	c->config_path = p;
+
+	/* Since we've changed the config path, we have to change the
+	 * config file name too */
+	if (!set_config_filename(c)) {
+		ERROR("Out of memory setting new config filename");
+		b = false;
+		free(c->config_path);
+		c->config_path = oldpath;
+		oldpath = NULL;
+	}
 err:
+	if (oldpath)
+		free(oldpath);
 	lxcunlock(c->privlock);
 	return b;
 }
@@ -938,10 +988,9 @@ out:
 }
 
 
-struct lxc_container *lxc_container_new(const char *name)
+struct lxc_container *lxc_container_new(const char *name, const char *configpath)
 {
 	struct lxc_container *c;
-	int ret, len;
 
 	c = malloc(sizeof(*c));
 	if (!c) {
@@ -950,7 +999,11 @@ struct lxc_container *lxc_container_new(const char *name)
 	}
 	memset(c, 0, sizeof(*c));
 
-	c->config_path = default_lxc_path();
+	if (configpath)
+		c->config_path = strdup(configpath);
+	else
+		c->config_path = default_lxc_path();
+
 	if (!c->config_path) {
 		fprintf(stderr, "Out of memory");
 		goto err;
@@ -976,17 +1029,10 @@ struct lxc_container *lxc_container_new(const char *name)
 		goto err;
 	}
 
-	len = strlen(c->config_path)+strlen(c->name)+strlen("/config")+2;
-	c->configfile = malloc(len);
-	if (!c->configfile) {
+	if (!set_config_filename(c)) {
 		fprintf(stderr, "Error allocating config file pathname\n");
 		goto err;
 	}
-	ret = snprintf(c->configfile, len, "%s/%s/config", c->config_path, c->name);
-	if (ret < 0 || ret >= len) {
-		fprintf(stderr, "Error printing out config file name\n");
-		goto err;
-	}
 
 	if (file_exists(c->configfile))
 		lxcapi_load_config(c, NULL);

src/lxc/lxccontainer.h

@@ -82,7 +82,7 @@ struct lxc_container {
 #endif
 };
 
-struct lxc_container *lxc_container_new(const char *name);
+struct lxc_container *lxc_container_new(const char *name, const char *configpath);
 int lxc_container_get(struct lxc_container *c);
 int lxc_container_put(struct lxc_container *c);
 int lxc_get_wait_states(const char **states);

src/python-lxc/lxc.c

@@ -85,7 +85,7 @@ Container_init(Container *self, PyObject *args, PyObject *kwds)
                                       &name))
         return -1;
 
-    self->container = lxc_container_new(name);
+    self->container = lxc_container_new(name, NULL);
     if (!self->container) {
         fprintf(stderr, "%d: error creating lxc_container %s\n", __LINE__, name);
         return -1;

src/tests/Makefile.am

@@ -15,6 +15,7 @@ lxc_test_createtest_SOURCES = createtest.c
 lxc_test_shutdowntest_SOURCES = shutdowntest.c
 lxc_test_get_item_SOURCES = get_item.c
 lxc_test_getkeys_SOURCES = getkeys.c
+lxc_test_lxcpath_SOURCES = lxcpath.c
 
 AM_CFLAGS=-I$(top_srcdir)/src \
 	-DLXCROOTFSMOUNT=\"$(LXCROOTFSMOUNT)\" \
@@ -24,6 +25,6 @@ AM_CFLAGS=-I$(top_srcdir)/src \
 
 bin_PROGRAMS = lxc-test-containertests lxc-test-locktests lxc-test-startone \
 	lxc-test-destroytest lxc-test-saveconfig lxc-test-createtest \
-	lxc-test-shutdowntest lxc-test-get_item lxc-test-getkeys
+	lxc-test-shutdowntest lxc-test-get_item lxc-test-getkeys lxc-test-lxcpath
 
 endif

src/tests/containertests.c

@@ -103,7 +103,7 @@ int main(int argc, char *argv[])
 
 	ret = 1;
 	/* test refcounting */
-	c = lxc_container_new(MYNAME);
+	c = lxc_container_new(MYNAME, NULL);
 	if (!c) {
 		fprintf(stderr, "%d: error creating lxc_container %s\n", __LINE__, MYNAME);
 		goto out;
@@ -149,7 +149,7 @@ int main(int argc, char *argv[])
 	}
 
 	/* test a real container */
-	c = lxc_container_new(MYNAME);
+	c = lxc_container_new(MYNAME, NULL);
 	if (!c) {
 		fprintf(stderr, "%d: error creating lxc_container %s\n", __LINE__, MYNAME);
 		ret = 1;

src/tests/createtest.c

@@ -33,7 +33,7 @@ int main(int argc, char *argv[])
 	struct lxc_container *c;
 	int ret = 1;
 
-	if ((c = lxc_container_new(MYNAME)) == NULL) {
+	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
 		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
 		ret = 1;
 		goto out;

src/tests/destroytest.c

@@ -65,7 +65,7 @@ int main(int argc, char *argv[])
 	struct lxc_container *c;
 	int ret = 1;
 
-	if ((c = lxc_container_new(MYNAME)) == NULL) {
+	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
 		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
 		ret = 1;
 		goto out;

src/tests/get_item.c

@@ -35,7 +35,7 @@ int main(int argc, char *argv[])
 	int ret;
 	char v1[2], v2[256], v3[2048];
 
-	if ((c = lxc_container_new("testxyz")) == NULL) {
+	if ((c = lxc_container_new("testxyz", NULL)) == NULL) {
 		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
 		ret = 1;
 		goto out;
@@ -157,7 +157,7 @@ int main(int argc, char *argv[])
 	lxc_container_put(c);
 
 	// new test with real container
-	if ((c = lxc_container_new(MYNAME)) == NULL) {
+	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
 		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
 		ret = 1;
 		goto out;
@@ -165,7 +165,7 @@ int main(int argc, char *argv[])
 	c->destroy(c);
 	lxc_container_put(c);
 
-	if ((c = lxc_container_new(MYNAME)) == NULL) {
+	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
 		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
 		ret = 1;
 		goto out;
@@ -179,7 +179,7 @@ int main(int argc, char *argv[])
 	lxc_container_put(c);
 
 	/* XXX TODO load_config needs to clear out any old config first */
-	if ((c = lxc_container_new(MYNAME)) == NULL) {
+	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
 		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
 		ret = 1;
 		goto out;

src/tests/getkeys.c

@@ -35,7 +35,7 @@ int main(int argc, char *argv[])
 	int len, ret;
 	char v3[2048];
 
-	if ((c = lxc_container_new(MYNAME)) == NULL) {
+	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
 		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
 		ret = 1;
 		goto out;

src/tests/lxcpath.c

+/* liblxcapi
+ *
+ * Copyright  2012 Serge Hallyn <serge.hallyn@ubuntu.com>.
+ * Copyright  2012 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+#include "../lxc/lxccontainer.h"
+
+#include <unistd.h>
+#include <signal.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <stdlib.h>
+#include <errno.h>
+
+#define MYNAME "lxctest1"
+
+#define TSTERR(x) do { \
+	fprintf(stderr, "%d: %s", __LINE__, x); \
+} while (0)
+
+int main()
+{
+	struct lxc_container *c;
+	const char *p1, *p2;
+	int retval = -1;
+
+	c = lxc_container_new(MYNAME, NULL);
+	if (!c) {
+		TSTERR("create using default path");
+		goto err;
+	}
+	p1 = c->get_config_path(c);
+	p2 = c->config_file_name(c);
+	if (!p1 || !p2 || strncmp(p1, p2, strlen(p1))) {
+		TSTERR("Bad result for path names");
+		goto err;
+	}
+
+#define CPATH "/boo"
+#define FPATH "/boo/lxctest1/config"
+	if (!c->set_config_path(c, "/boo")) {
+		TSTERR("Error setting custom path");
+		goto err;
+	}
+	p1 = c->get_config_path(c);
+	p2 = c->config_file_name(c);
+	if (strcmp(p1, CPATH) || strcmp(p2, FPATH)) {
+		TSTERR("Bad result for path names after set_config_path()");
+		goto err;
+	}
+	lxc_container_put(c);
+
+	c = lxc_container_new(MYNAME, CPATH);
+	if (!c) {
+		TSTERR("create using custom path");
+		goto err;
+	}
+
+	p1 = c->get_config_path(c);
+	p2 = c->config_file_name(c);
+	if (strcmp(p1, CPATH) || strcmp(p2, FPATH)) {
+		TSTERR("Bad result for path names after create with custom path");
+		goto err;
+	}
+
+	retval = 0;
+
+err:
+	lxc_container_put(c);
+	return retval;
+}

src/tests/saveconfig.c

@@ -65,7 +65,7 @@ int main(int argc, char *argv[])
 	struct lxc_container *c;
 	int ret = 1;
 
-	if ((c = lxc_container_new(MYNAME)) == NULL) {
+	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
 		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
 		ret = 1;
 		goto out;

src/tests/shutdowntest.c

@@ -34,7 +34,7 @@ int main(int argc, char *argv[])
 	struct lxc_container *c;
 	int ret = 1;
 
-	if ((c = lxc_container_new(MYNAME)) == NULL) {
+	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
 		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
 		ret = 1;
 		goto out;

src/tests/startone.c

@@ -103,7 +103,7 @@ int main(int argc, char *argv[])
 
 	ret = 1;
 	/* test a real container */
-	c = lxc_container_new(MYNAME);
+	c = lxc_container_new(MYNAME, NULL);
 	if (!c) {
 		fprintf(stderr, "%d: error creating lxc_container %s\n", __LINE__, MYNAME);
 		ret = 1;