cgfsng: Add new macro to print errors

At this point, macros such DEBUG or ERROR does not take effect because
this code is called from cgroup_ops_init(cgroup.c), which runs with
__attribute__((constructor)), before any log level is set form any tool
like lxc-start, so these messages are lost.

For now on, use the same LXC_DEBUG_CGFSNG environment variable to
control these messages.

Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>

diff --git a/src/lxc/cgroups/cgfsng.c b/src/lxc/cgroups/cgfsng.c
index 195897e6d2a2a720aa12612b66a190885430784e..e13d5cadf8de5202dc52ca59d7699d8e97013ae2 100644 (file)
--- a/src/lxc/cgroups/cgfsng.c
+++ b/src/lxc/cgroups/cgfsng.c
@@ -118,6 +118,11 @@ char *cgroup_use;
  */
 static bool lxc_cgfsng_debug;
 
+#define CGFSNG_DEBUG(format, ...) do {         \
+       if (lxc_cgfsng_debug)                   \
+               printf("cgfsng: " format, ##__VA_ARGS__);       \
+} while(0)
+
 static void free_string_list(char **clist)
 {
        if (clist) {
@@ -727,7 +732,7 @@ static bool all_controllers_found(void)
        struct hierarchy ** hlist = hierarchies;
 
        if (!controller_found(hlist, "freezer")) {
-               ERROR("No freezer controller mountpoint found");
+               CGFSNG_DEBUG("No freezer controller mountpoint found\n");
                return false;
        }
 
@@ -737,7 +742,7 @@ static bool all_controllers_found(void)
        for (p = strtok_r(cgroup_use, ",", &saveptr); p;
                        p = strtok_r(NULL, ",", &saveptr)) {
                if (!controller_found(hlist, p)) {
-                       ERROR("No %s controller mountpoint found", p);
+                       CGFSNG_DEBUG("No %s controller mountpoint found\n", p);
                        return false;
                }
        }
@@ -770,13 +775,13 @@ static char **get_controllers(char **klist, char **nlist, char *line, int type)
        /* note - if we change how mountinfo works, then our caller
         * will need to verify /sys/fs/cgroup/ in this field */
        if (strncmp(p, "/sys/fs/cgroup/", 15)) {
-               INFO("Found hierarchy not under /sys/fs/cgroup: \"%s\"", p);
+               CGFSNG_DEBUG("Found hierarchy not under /sys/fs/cgroup: \"%s\"\n", p);
                return NULL;
        }
        p += 15;
        p2 = strchr(p, ' ');
        if (!p2) {
-               ERROR("Corrupt mountinfo");
+               CGFSNG_DEBUG("Corrupt mountinfo\n");
                return NULL;
        }
        *p2 = '\0';
@@ -1068,7 +1073,7 @@ static bool parse_hierarchies(void)
                return false;
 
        if ((f = fopen("/proc/self/mountinfo", "r")) == NULL) {
-               SYSERROR("Failed to open \"/proc/self/mountinfo\"");
+               CGFSNG_DEBUG("Failed to open \"/proc/self/mountinfo\"\n");
                return false;
        }
 
@@ -1099,14 +1104,14 @@ static bool parse_hierarchies(void)
 
                mountpoint = get_mountpoint(line);
                if (!mountpoint) {
-                       ERROR("Failed parsing mountpoint from \"%s\"", line);
+                       CGFSNG_DEBUG("Failed parsing mountpoint from \"%s\"\n", line);
                        free_string_list(controller_list);
                        continue;
                }
 
                base_cgroup = get_current_cgroup(basecginfo, controller_list[0]);
                if (!base_cgroup) {
-                       ERROR("Failed to find current cgroup for controller \"%s\"", controller_list[0]);
+                       CGFSNG_DEBUG("Failed to find current cgroup for controller \"%s\"\n", controller_list[0]);
                        free_string_list(controller_list);
                        free(mountpoint);
                        continue;
@@ -1155,7 +1160,7 @@ static bool collect_hierarchy_info(void)
        errno = 0;
        tmp = lxc_global_config_value("lxc.cgroup.use");
        if (!cgroup_use && errno != 0) { /* lxc.cgroup.use can be NULL */
-               ERROR("Failed to retrieve list of cgroups to use");
+               CGFSNG_DEBUG("Failed to retrieve list of cgroups to use\n");
                return false;
        }
        cgroup_use = must_copy_string(tmp);