confile_utils: add new file

src/lxc/Makefile.am

@@ -20,6 +20,8 @@ noinst_HEADERS = \
 	cgroups/cgroup.h \
 	caps.h \
 	conf.h \
+	confile.h \
+	confile_utils.h \
 	console.h \
 	error.h \
 	initutils.h \
@@ -101,6 +103,7 @@ liblxc_la_SOURCES = \
 	namespace.h namespace.c \
 	conf.c conf.h \
 	confile.c confile.h \
+	confile_utils.c confile_utils.h \
 	list.h \
 	state.c state.h \
 	log.c log.h \

src/lxc/confile.c

@@ -45,6 +45,7 @@
 #include "parse.h"
 #include "config.h"
 #include "confile.h"
+#include "confile_utils.h"
 #include "utils.h"
 #include "log.h"
 #include "conf.h"
@@ -1984,8 +1985,7 @@ static int set_config_idmaps(const char *key, const char *value,
 {
 	unsigned long hostid, nsid, range;
 	char type;
-	char *window, *slide;
-	char *dup = NULL;
+	int ret;
 	struct lxc_list *idmaplist = NULL;
 	struct id_map *idmap = NULL;
 
@@ -2001,109 +2001,10 @@ static int set_config_idmaps(const char *key, const char *value,
 		goto on_error;
 	memset(idmap, 0, sizeof(*idmap));
 
-	/* Duplicate string. */
-	dup = strdup(value);
-	if (!dup)
+	ret = parse_idmaps(value, &type, &nsid, &hostid, &range);
+	if (ret < 0)
 		goto on_error;
 
-	/* A prototypical idmap entry would be: "u 1000 1000000 65536" */
-
-	/* align */
-        slide = window = dup;
-        /* skip whitespace */
-        slide += strspn(slide, " \t\r");
-        if (slide != window && *slide == '\0')
-                goto on_error;
-
-	/* Validate type. */
-        if (*slide != 'u' && *slide != 'g')
-                goto on_error;
-        /* Assign type. */
-        type = *slide;
-
-	/* move beyond type */
-        slide++;
-	/* align */
-        window = slide;
-        /* Validate that only whitespace follows. */
-        slide += strspn(slide, " \t\r");
-	/* There must be whitespace. */
-        if (slide == window)
-                goto on_error;
-
-        /* Mark beginning of nsuid. */
-        window = slide;
-	/* Validate that non-whitespace follows. */
-        slide += strcspn(slide, " \t\r");
-	/* There must be non-whitespace. */
-        if (slide == window || *slide == '\0')
-                goto on_error;
-        /* Mark end of nsuid. */
-        *slide = '\0';
-
-        /* Parse nsuid. */
-        if (lxc_safe_ulong(window, &nsid) < 0)
-                goto on_error;
-
-	/* Move beyond \0. */
-        slide++;
-	/* align */
-        window = slide;
-        /* Validate that only whitespace follows. */
-        slide += strspn(slide, " \t\r");
-	/* If there was only one whitespace then we whiped it with our \0 above.
-	 * So only ensure that we're not at the end of the string.
-	 */
-	if (*slide == '\0')
-                goto on_error;
-
-        /* Mark beginning of hostid. */
-        window = slide;
-	/* Validate that non-whitespace follows. */
-        slide += strcspn(slide, " \t\r");
-	/* There must be non-whitespace. */
-        if (slide == window || *slide == '\0')
-                goto on_error;
-        /* Mark end of nsuid. */
-        *slide = '\0';
-
-        /* Parse hostid. */
-        if (lxc_safe_ulong(window, &hostid) < 0)
-                goto on_error;
-
-	/* Move beyond \0. */
-        slide++;
-	/* align */
-        window = slide;
-        /* Validate that only whitespace follows. */
-        slide += strspn(slide, " \t\r");
-	/* If there was only one whitespace then we whiped it with our \0 above.
-	 * So only ensure that we're not at the end of the string.
-	 */
-        if (*slide == '\0')
-                goto on_error;
-
-        /* Mark beginning of range. */
-        window = slide;
-	/* Validate that non-whitespace follows. */
-        slide += strcspn(slide, " \t\r");
-	/* There must be non-whitespace. */
-        if (slide == window)
-                goto on_error;
-
-	/* The range is the last valid entry we expect. So make sure that there
-	 * is not trailing garbage and if there is, error out.
-	 */
-	if (*(slide + strspn(slide, " \t\r\n")) != '\0')
-                goto on_error;
-        /* Mark end of range. */
-        *slide = '\0';
-
-        /* Parse range. */
-        if (lxc_safe_ulong(window, &range) < 0)
-                goto on_error;
-
-	/* Yay, we survived. */
 	INFO("read uid map: type %c nsid %lu hostid %lu range %lu", type, nsid, hostid, range);
 	if (type == 'u')
 		idmap->idtype = ID_TYPE_UID;
@@ -2124,7 +2025,6 @@ static int set_config_idmaps(const char *key, const char *value,
 on_error:
 	free(idmaplist);
 	free(idmap);
-	free(dup);
 
 	return -1;
 }

src/lxc/confile_utils.c

+/* liblxcapi
+ *
+ * Copyright © 2017 Christian Brauner <christian.brauner@ubuntu.com>.
+ * Copyright © 2017 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 <stdio.h>
+#include <string.h>
+
+#include "utils.h"
+
+int parse_idmaps(const char *idmap, char *type, unsigned long *nsid,
+		 unsigned long *hostid, unsigned long *range)
+{
+	int ret = -1;
+	unsigned long tmp_hostid, tmp_nsid, tmp_range;
+	char tmp_type;
+	char *window, *slide;
+	char *dup = NULL;
+
+	/* Duplicate string. */
+	dup = strdup(idmap);
+	if (!dup)
+		goto on_error;
+
+	/* A prototypical idmap entry would be: "u 1000 1000000 65536" */
+
+	/* align */
+	slide = window = dup;
+	/* skip whitespace */
+	slide += strspn(slide, " \t\r");
+	if (slide != window && *slide == '\0')
+		goto on_error;
+
+	/* Validate type. */
+	if (*slide != 'u' && *slide != 'g')
+		goto on_error;
+	/* Assign type. */
+	tmp_type = *slide;
+
+	/* move beyond type */
+	slide++;
+	/* align */
+	window = slide;
+	/* Validate that only whitespace follows. */
+	slide += strspn(slide, " \t\r");
+	/* There must be whitespace. */
+	if (slide == window)
+		goto on_error;
+
+	/* Mark beginning of nsuid. */
+	window = slide;
+	/* Validate that non-whitespace follows. */
+	slide += strcspn(slide, " \t\r");
+	/* There must be non-whitespace. */
+	if (slide == window || *slide == '\0')
+		goto on_error;
+	/* Mark end of nsuid. */
+	*slide = '\0';
+
+	/* Parse nsuid. */
+	if (lxc_safe_ulong(window, &tmp_nsid) < 0)
+		goto on_error;
+
+	/* Move beyond \0. */
+	slide++;
+	/* align */
+	window = slide;
+	/* Validate that only whitespace follows. */
+	slide += strspn(slide, " \t\r");
+	/* If there was only one whitespace then we whiped it with our \0 above.
+	 * So only ensure that we're not at the end of the string.
+	 */
+	if (*slide == '\0')
+		goto on_error;
+
+	/* Mark beginning of hostid. */
+	window = slide;
+	/* Validate that non-whitespace follows. */
+	slide += strcspn(slide, " \t\r");
+	/* There must be non-whitespace. */
+	if (slide == window || *slide == '\0')
+		goto on_error;
+	/* Mark end of nsuid. */
+	*slide = '\0';
+
+	/* Parse hostid. */
+	if (lxc_safe_ulong(window, &tmp_hostid) < 0)
+		goto on_error;
+
+	/* Move beyond \0. */
+	slide++;
+	/* align */
+	window = slide;
+	/* Validate that only whitespace follows. */
+	slide += strspn(slide, " \t\r");
+	/* If there was only one whitespace then we whiped it with our \0 above.
+	 * So only ensure that we're not at the end of the string.
+	 */
+	if (*slide == '\0')
+		goto on_error;
+
+	/* Mark beginning of range. */
+	window = slide;
+	/* Validate that non-whitespace follows. */
+	slide += strcspn(slide, " \t\r");
+	/* There must be non-whitespace. */
+	if (slide == window)
+		goto on_error;
+
+	/* The range is the last valid entry we expect. So make sure that there
+	 * is not trailing garbage and if there is, error out.
+	 */
+	if (*(slide + strspn(slide, " \t\r\n")) != '\0')
+		goto on_error;
+	/* Mark end of range. */
+	*slide = '\0';
+
+	/* Parse range. */
+	if (lxc_safe_ulong(window, &tmp_range) < 0)
+		goto on_error;
+
+	*type = tmp_type;
+	*nsid = tmp_nsid;
+	*hostid = tmp_hostid;
+	*range = tmp_range;
+
+	/* Yay, we survived. */
+	ret = 0;
+
+on_error:
+	free(dup);
+
+	return ret;
+}

src/lxc/confile_utils.h

+/* liblxcapi
+ *
+ * Copyright © 2017 Christian Brauner <christian.brauner@ubuntu.com>.
+ * Copyright © 2017 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.
+ */
+
+#ifndef __LXC_CONFILE_UTILS_H
+#define __LXC_CONFILE_UTILS_H
+
+extern int parse_idmaps(const char *idmap, char *type, unsigned long *nsid,
+			unsigned long *hostid, unsigned long *range);
+
+#endif /* __LXC_CONFILE_UTILS_H */