[lxc-devel] [lxc/master] store criu version

[brauner on Github]

A non-text attachment was scrubbed...
Name: not available
Type: text/x-mailbox
Size: 668 bytes
Desc: not available
URL: <http://lists.linuxcontainers.org/pipermail/lxc-devel/attachments/20160705/19d55174/attachment.bin>
-------------- next part --------------
From 428526eae2d96e2ac7acaaf75fba8c25fe573ab3 Mon Sep 17 00:00:00 2001
From: Christian Brauner <christian.brauner at mailbox.org>
Date: Tue, 5 Jul 2016 16:52:21 +0200
Subject: [PATCH] store criu version

- rename criu_version_ok() --> criu_version(char *version)
- If version != NULL criu_version() stores the detected criu version in
  version. Allocates memory for version which must be freed by caller.
- If version == NULL criu_version() will return true when the version matches,
  false in all other cases.

Signed-off-by: Christian Brauner <cbrauner at suse.de>
---
 src/lxc/criu.c | 26 +++++++++++++++++++-------
 1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/src/lxc/criu.c b/src/lxc/criu.c
index a1b7d40..0c89bb7 100644
--- a/src/lxc/criu.c
+++ b/src/lxc/criu.c
@@ -402,8 +402,11 @@ static void exec_criu(struct criu_opts *opts)
  *
  * The intent is that when criu development slows down, we can drop this, but
  * for now we shouldn't attempt to c/r with versions that we know won't work.
+ *
+ * Note: If version != NULL criu_version() stores the detected criu version in
+ * version. Allocates memory for version which must be freed by caller.
  */
-static bool criu_version_ok()
+static bool criu_version_ok(char *version)
 {
 	int pipes[2];
 	pid_t pid;
@@ -436,7 +439,7 @@ static bool criu_version_ok()
 		exit(1);
 	} else {
 		FILE *f;
-		char version[1024];
+		char *tmp;
 		int patch;
 
 		close(pipes[1]);
@@ -452,16 +455,20 @@ static bool criu_version_ok()
 			return false;
 		}
 
-		if (fscanf(f, "Version: %1023[^\n]s", version) != 1)
+		tmp = malloc(1024);
+		if (!tmp)
+			return false;
+
+		if (fscanf(f, "Version: %1023[^\n]s", tmp) != 1)
 			goto version_error;
 
 		if (fgetc(f) != '\n')
 			goto version_error;
 
-		if (strcmp(version, CRIU_VERSION) >= 0)
+		if (strcmp(tmp, CRIU_VERSION) >= 0)
 			goto version_match;
 
-		if (fscanf(f, "GitID: v%1023[^-]s", version) != 1)
+		if (fscanf(f, "GitID: v%1023[^-]s", tmp) != 1)
 			goto version_error;
 
 		if (fgetc(f) != '-')
@@ -470,7 +477,7 @@ static bool criu_version_ok()
 		if (fscanf(f, "%d", &patch) != 1)
 			goto version_error;
 
-		if (strcmp(version, CRIU_GITID_VERSION) < 0)
+		if (strcmp(tmp, CRIU_GITID_VERSION) < 0)
 			goto version_error;
 
 		if (patch < CRIU_GITID_PATCHLEVEL)
@@ -478,10 +485,15 @@ static bool criu_version_ok()
 
 version_match:
 		fclose(f);
+		if (!version)
+			free(tmp);
+		else
+			version = tmp;
 		return true;
 
 version_error:
 		fclose(f);
+		free(tmp);
 		ERROR("must have criu " CRIU_VERSION " or greater to checkpoint/restore\n");
 		return false;
 	}
@@ -493,7 +505,7 @@ static bool criu_ok(struct lxc_container *c)
 {
 	struct lxc_list *it;
 
-	if (!criu_version_ok())
+	if (!criu_version_ok(NULL))
 		return false;
 
 	if (geteuid()) {