use a default per-container logfile

[ Thanks to Stéphane and Dwight for the feedback on the previous patch ]

Until now, if a lxc-* (i.e. lxc-start) command did not specify a logfile
(with -o logfile), the default was effectively 'none'.  With this patch,
the default becomes $LOGPATH/<container>/<container>.log.  LOGPATH is
specified at configure time with '--with-log-path='.  If unspecified, it
is $LXCPATH, so that logs for container r2 will show up at
/var/lib/lxc/r2/r2/log.  LOGPATH must exist, while lxc will make sure to
create $LOGPATH/<name>.  As another example, Ubuntu will likely specify
--with-log-path=/var/log/lxc (and place /var/log/lxc into
debian/lxc.dirs), placing r2's logs in /var/log/lxc/r2/r2.log.

If a container config file specifies 'lxc.logfile', that will override
the default.  If a '-o logfile' argument is specifed at lxc-start,
then that will override both the default and the configuration file
entry.  Finally, '-o none' can be used to avoid having a logfile at
all (in other words, the previous default), and that will override
a lxc.logfile entry in the container configuration file.

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>

diff --git a/configure.ac b/configure.ac
index d1f5ad950f9c27baeaf5d5d6006b5f0aef968237..6888701c98e87f5369d75099baece3e322c236b9 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -157,6 +157,13 @@ AC_ARG_WITH([rootfs-path],
                [lxc rootfs mount point]
        )], [], [with_rootfs_path=['${libdir}/lxc/rootfs']])
 
+# Container log path.  By default, use $lxcpath.
+AC_ARG_WITH([log-path],
+       [AC_HELP_STRING(
+               [--with-log-path=dir],
+               [per container log path]
+       )], [], [with_log_path=['${with_config_path}']])
+
 # Expand some useful variables
 AS_AC_EXPAND(PREFIX, "$prefix")
 AS_AC_EXPAND(LIBDIR, "$libdir")
@@ -173,6 +180,7 @@ AS_AC_EXPAND(LXCPATH, "$with_config_path")
 AS_AC_EXPAND(LXCROOTFSMOUNT, "$with_rootfs_path")
 AS_AC_EXPAND(LXCTEMPLATEDIR, "$datadir/lxc/templates")
 AS_AC_EXPAND(LXCINITDIR, "$libexecdir")
+AS_AC_EXPAND(LOGPATH, "$with_log_path")
 
 # Check for some standard kernel headers
 AC_CHECK_HEADERS([linux/unistd.h linux/netlink.h linux/genetlink.h],

diff --git a/src/lxc/Makefile.am b/src/lxc/Makefile.am
index 5a28af4c999ec7ad63185deb55dc5d5cfd63dc80..8b409268d8a8a41f2a7b38842ed85a65685dd7da 100644 (file)
--- a/src/lxc/Makefile.am
+++ b/src/lxc/Makefile.am
@@ -89,7 +89,8 @@ AM_CFLAGS=-I$(top_srcdir)/src \
        -DLXCROOTFSMOUNT=\"$(LXCROOTFSMOUNT)\" \
        -DLXCPATH=\"$(LXCPATH)\" \
        -DLXCINITDIR=\"$(LXCINITDIR)\" \
-       -DLXCTEMPLATEDIR=\"$(LXCTEMPLATEDIR)\"
+       -DLXCTEMPLATEDIR=\"$(LXCTEMPLATEDIR)\" \
+       -DLOGPATH=\"$(LOGPATH)\"
 
 if ENABLE_APPARMOR
 AM_CFLAGS += -DHAVE_APPARMOR

diff --git a/src/lxc/confile.c b/src/lxc/confile.c
index 67a989ed43650060f4280ffa82a08e729178b184..d350f01df1c8c5c1548028506d112832607cc3c8 100644 (file)
--- a/src/lxc/confile.c
+++ b/src/lxc/confile.c
@@ -927,11 +927,6 @@ static int config_aa_profile(const char *key, const char *value,
 static int config_logfile(const char *key, const char *value,
                             struct lxc_conf *lxc_conf)
 {
-       if (lxc_log_get_file()) {
-               DEBUG("Log file already specified - ignoring new value");
-               return 0;
-       }
-
        return lxc_log_set_file(value);
 }
 

diff --git a/src/lxc/log.c b/src/lxc/log.c
index d2a90de7a6846045cd0564d7a24935031aa94107..db5c52f369aaeafb4dbab194416cae633589c6e3 100644 (file)
--- a/src/lxc/log.c
+++ b/src/lxc/log.c
@@ -42,6 +42,8 @@
 int lxc_log_fd = -1;
 static char log_prefix[LXC_LOG_PREFIX_SIZE] = "lxc";
 static int lxc_loglevel_specified = 0;
+// if logfile was specifed on command line, it won't be overridden by lxc.logfile
+static int lxc_log_specified = 0;
 
 lxc_log_define(lxc_log, lxc);
 
@@ -148,11 +150,42 @@ static int log_open(const char *name)
        return newfd;
 }
 
+static char *build_log_path(const char *name)
+{
+       char *p;
+       int len, ret;
+
+       /* '$logpath' + '/' + '$name' + '/' + '$name' + '.log' + '\0' */
+       len = sizeof(LOGPATH) + 2*sizeof(name) + 7;
+       p = malloc(len);
+       if (!p)
+               return p;
+       ret = snprintf(p, len, "%s/%s", LOGPATH, name);
+       if (ret < 0 || ret >= len) {
+               free(p);
+               return NULL;
+       }
+       ret = mkdir(p, 0755);
+       if (ret == -1 && errno != EEXIST) {
+               free(p);
+               return NULL;
+       }
+       ret = snprintf(p, len, "%s/%s/%s.log", LOGPATH, name, name);
+       if (ret < 0 || ret >= len) {
+               free(p);
+               return NULL;
+       }
+       return p;
+}
+
 /*---------------------------------------------------------------------------*/
-extern int lxc_log_init(const char *file, const char *priority,
-                       const char *prefix, int quiet)
+extern int lxc_log_init(const char *name, const char *file,
+                       const char *priority, const char *prefix, int quiet)
 {
        int lxc_priority = LXC_LOG_PRIORITY_ERROR;
+       int ret;
+       char *tmpfile = NULL;
+       int want_lxc_log_specified = 0;
 
        if (lxc_log_fd != -1)
                return 0;
@@ -176,10 +209,30 @@ extern int lxc_log_init(const char *file, const char *priority,
        if (prefix)
                lxc_log_setprefix(prefix);
 
-       if (file)
-               return lxc_log_set_file(file);
+       if (file && strcmp(file, "none") == 0) {
+               want_lxc_log_specified = 1;
+               return 0;
+       }
 
-       return 0;
+       if (!file) {
+               tmpfile = build_log_path(name);
+               if (!tmpfile) {
+                       ERROR("could not build log path");
+                       return -1;
+               }
+       } else {
+               want_lxc_log_specified = 1;
+       }
+
+       ret = lxc_log_set_file(tmpfile ? tmpfile : file);
+
+       if (want_lxc_log_specified)
+               lxc_log_specified = 1;
+
+       if (tmpfile)
+               free(tmpfile);
+
+       return ret;
 }
 
 /*
@@ -202,16 +255,23 @@ extern int lxc_log_set_level(int level)
 char *log_fname;  // default to NULL, set in lxc_log_set_file.
 
 /*
- * This is called when we read a lxc.logfile entry in a lxc.conf file.  This
- * happens after processing command line arguments, which override the .conf
- * settings.  So only set the logfile if previously unset.
+ * This can be called:
+ *   1. when a program calls lxc_log_init with no logfile parameter (in which
+ *      case the default is used).  In this case lxc.logfile can override this.
+ *   2. when a program calls lxc_log_init with a logfile parameter.  In this
+ *     case we don't want lxc.logfile to override this.
+ *   3. When a lxc.logfile entry is found in config file.
  */
 extern int lxc_log_set_file(const char *fname)
 {
+       if (lxc_log_specified) {
+               INFO("lxc.logfile overriden by command line");
+               return 0;
+       }
        if (lxc_log_fd != -1) {
-               // this should've been caught at config_logfile.
-               ERROR("Race in setting logfile?");
-               return -1;
+               // we are overriding the default.
+               close(lxc_log_fd);
+               free(log_fname);
        }
 
        lxc_log_fd = log_open(fname);

diff --git a/src/lxc/log.h b/src/lxc/log.h
index a9260f22a48cf84ac989ca1a93bd5e4e6dfca2c1..771995865428643b6658eb6629d34718f8f07c0e 100644 (file)
--- a/src/lxc/log.h
+++ b/src/lxc/log.h
@@ -287,8 +287,8 @@ extern struct lxc_log_category lxc_log_category_lxc;
 
 extern int lxc_log_fd;
 
-extern int lxc_log_init(const char *file, const char *priority,
-                       const char *prefix, int quiet);
+extern int lxc_log_init(const char *name, const char *file,
+                       const char *priority, const char *prefix, int quiet);
 
 extern void lxc_log_setprefix(const char *a_prefix);
 extern int lxc_log_set_level(int level);

diff --git a/src/lxc/lxc_attach.c b/src/lxc/lxc_attach.c
index 851a37aaa11be101daad9255f652596ad57d4ca3..437a40080defa358ea8ab02c670e3709b4a94379 100644 (file)
--- a/src/lxc/lxc_attach.c
+++ b/src/lxc/lxc_attach.c
@@ -139,7 +139,7 @@ int main(int argc, char *argv[])
        if (ret)
                return ret;
 
-       ret = lxc_log_init(my_args.log_file, my_args.log_priority,
+       ret = lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
                           my_args.progname, my_args.quiet);
        if (ret)
                return ret;

diff --git a/src/lxc/lxc_cgroup.c b/src/lxc/lxc_cgroup.c
index 97769a5a266cce95559db69f018dbf5eba138822..970391ba2785e5bd212a329975dfeb0a555b8c81 100644 (file)
--- a/src/lxc/lxc_cgroup.c
+++ b/src/lxc/lxc_cgroup.c
@@ -68,7 +68,7 @@ int main(int argc, char *argv[])
        if (lxc_arguments_parse(&my_args, argc, argv))
                return -1;
 
-       if (lxc_log_init(my_args.log_file, my_args.log_priority,
+       if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
                         my_args.progname, my_args.quiet))
                return -1;
 

diff --git a/src/lxc/lxc_checkpoint.c b/src/lxc/lxc_checkpoint.c
index 76f6709f299c9b0beb9f4cea9d2b3c60bd16b8ec..a15175015fd6cd99ee96a67792920f77a6d1e6a1 100644 (file)
--- a/src/lxc/lxc_checkpoint.c
+++ b/src/lxc/lxc_checkpoint.c
@@ -115,7 +115,7 @@ int main(int argc, char *argv[])
        if (ret)
                return ret;
 
-       ret = lxc_log_init(my_args.log_file, my_args.log_priority,
+       ret = lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
                           my_args.progname, my_args.quiet);
        if (ret)
                return ret;

diff --git a/src/lxc/lxc_console.c b/src/lxc/lxc_console.c
index d09c6882ea650daabb91f950e44a1e71a32f18b3..c263d0f81bc7b4468cdd8495e1ecce21147c550e 100644 (file)
--- a/src/lxc/lxc_console.c
+++ b/src/lxc/lxc_console.c
@@ -187,7 +187,7 @@ int main(int argc, char *argv[])
        if (err)
                return -1;
 
-       err = lxc_log_init(my_args.log_file, my_args.log_priority,
+       err = lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
                           my_args.progname, my_args.quiet);
        if (err)
                return -1;

diff --git a/src/lxc/lxc_execute.c b/src/lxc/lxc_execute.c
index 1eb25a7da879e53fee8d32f82949710e947a70e8..9377f4f31156f7032f41c7a2df19030c084d8934 100644 (file)
--- a/src/lxc/lxc_execute.c
+++ b/src/lxc/lxc_execute.c
@@ -99,7 +99,7 @@ int main(int argc, char *argv[])
        if (lxc_arguments_parse(&my_args, argc, argv))
                return -1;
 
-       if (lxc_log_init(my_args.log_file, my_args.log_priority,
+       if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
                         my_args.progname, my_args.quiet))
                return -1;
 

diff --git a/src/lxc/lxc_freeze.c b/src/lxc/lxc_freeze.c
index 770d923ffaca979a98faa904f0c503f0b1e90cb0..4da56548435b68e750851c170b44968660bb9040 100644 (file)
--- a/src/lxc/lxc_freeze.c
+++ b/src/lxc/lxc_freeze.c
@@ -54,7 +54,7 @@ int main(int argc, char *argv[])
        if (lxc_arguments_parse(&my_args, argc, argv))
                return -1;
 
-       if (lxc_log_init(my_args.log_file, my_args.log_priority,
+       if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
                         my_args.progname, my_args.quiet))
                return -1;
 

diff --git a/src/lxc/lxc_info.c b/src/lxc/lxc_info.c
index 1a1cc22df36550cf16dcb3661b1a76605ff89229..48c1370de32a7573dcd31d16b2f9803381608213 100644 (file)
--- a/src/lxc/lxc_info.c
+++ b/src/lxc/lxc_info.c
@@ -79,7 +79,7 @@ int main(int argc, char *argv[])
        if (ret)
                return 1;
 
-       if (lxc_log_init(my_args.log_file, my_args.log_priority,
+       if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
                         my_args.progname, my_args.quiet))
                return 1;
 

diff --git a/src/lxc/lxc_init.c b/src/lxc/lxc_init.c
index 2263cd16f1c1a1d9b6d07c3e2245bf11c8e69264..90e1ad6618f6d5c025279b2a71c98bd36c3b15df 100644 (file)
--- a/src/lxc/lxc_init.c
+++ b/src/lxc/lxc_init.c
@@ -79,7 +79,7 @@ int main(int argc, char *argv[])
        if (lxc_caps_init())
                exit(err);
 
-       if (lxc_log_init(NULL, 0, basename(argv[0]), quiet))
+       if (lxc_log_init(NULL, "none", 0, basename(argv[0]), quiet))
                exit(err);
 
        if (!argv[optind]) {

diff --git a/src/lxc/lxc_kill.c b/src/lxc/lxc_kill.c
index 3d996a5c7fc292b8bb8868c8e473fde2bb6fc3d9..f9bfe34b60e812b454737a10b22962ee9b3aad4a 100644 (file)
--- a/src/lxc/lxc_kill.c
+++ b/src/lxc/lxc_kill.c
@@ -61,7 +61,7 @@ int main(int argc, char *argv[], char *envp[])
        if (ret)
                return ret;
 
-       ret = lxc_log_init(my_args.log_file, my_args.log_priority,
+       ret = lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
                           my_args.progname, my_args.quiet);
        if (ret)
                return ret;

diff --git a/src/lxc/lxc_monitor.c b/src/lxc/lxc_monitor.c
index 4bd6ab0156340a27e04d435ff8b779fe75fd7450..2b8b0a0864e815a36dd116d47cb0d21b05d3f4ed 100644 (file)
--- a/src/lxc/lxc_monitor.c
+++ b/src/lxc/lxc_monitor.c
@@ -65,7 +65,7 @@ int main(int argc, char *argv[])
        if (lxc_arguments_parse(&my_args, argc, argv))
                return -1;
 
-       if (lxc_log_init(my_args.log_file, my_args.log_priority,
+       if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
                         my_args.progname, my_args.quiet))
                return -1;
 

diff --git a/src/lxc/lxc_restart.c b/src/lxc/lxc_restart.c
index 75486821cb34161da3248c6790b348425cded036..1cf9462e9395aee690e9866d6bb241fb50a791b4 100644 (file)
--- a/src/lxc/lxc_restart.c
+++ b/src/lxc/lxc_restart.c
@@ -122,7 +122,7 @@ int main(int argc, char *argv[])
        if (lxc_arguments_parse(&my_args, argc, argv))
                return -1;
 
-       if (lxc_log_init(my_args.log_file, my_args.log_priority,
+       if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
                         my_args.progname, my_args.quiet))
                return -1;
 

diff --git a/src/lxc/lxc_start.c b/src/lxc/lxc_start.c
index a97dccaa86cbb78245d472daa90bd12673781f06..b64acffe3a52af29a124940e4668bb7d314308db 100644 (file)
--- a/src/lxc/lxc_start.c
+++ b/src/lxc/lxc_start.c
@@ -164,7 +164,7 @@ int main(int argc, char *argv[])
        else
                args = my_args.argv;
 
-       if (lxc_log_init(my_args.log_file, my_args.log_priority,
+       if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
                         my_args.progname, my_args.quiet))
                return err;
 

diff --git a/src/lxc/lxc_stop.c b/src/lxc/lxc_stop.c
index 639b7500be35a9e88c41fadce45a4198740f1d00..749d78a65b97629d74e93765ac4caed9943ef79c 100644 (file)
--- a/src/lxc/lxc_stop.c
+++ b/src/lxc/lxc_stop.c
@@ -53,7 +53,7 @@ int main(int argc, char *argv[])
        if (lxc_arguments_parse(&my_args, argc, argv))
                return -1;
 
-       if (lxc_log_init(my_args.log_file, my_args.log_priority,
+       if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
                         my_args.progname, my_args.quiet))
                return -1;
 

diff --git a/src/lxc/lxc_unfreeze.c b/src/lxc/lxc_unfreeze.c
index 22be8395b0123a2c1c699f8183aee4e7f5ef42d3..02e9a47c938fc27db78d4683285d9aefc3c701f6 100644 (file)
--- a/src/lxc/lxc_unfreeze.c
+++ b/src/lxc/lxc_unfreeze.c
@@ -53,7 +53,7 @@ int main(int argc, char *argv[])
        if (lxc_arguments_parse(&my_args, argc, argv))
                return -1;
 
-       if (lxc_log_init(my_args.log_file, my_args.log_priority,
+       if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
                         my_args.progname, my_args.quiet))
                return -1;
 

diff --git a/src/lxc/lxc_wait.c b/src/lxc/lxc_wait.c
index 799225d970df75998d01162e1354c6802bebd92e..b0643c73946ad7c1018687013e5398943631f773 100644 (file)
--- a/src/lxc/lxc_wait.c
+++ b/src/lxc/lxc_wait.c
@@ -83,7 +83,7 @@ int main(int argc, char *argv[])
        if (lxc_arguments_parse(&my_args, argc, argv))
                return -1;
 
-       if (lxc_log_init(my_args.log_file, my_args.log_priority,
+       if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
                         my_args.progname, my_args.quiet))
                return -1;
 

diff --git a/src/lxc/lxccontainer.c b/src/lxc/lxccontainer.c
index 5919d2c574acca258cafa3e49c5dfe6679c0463f..502a7a73af0e80ab525eb84013db974002d9cd69 100644 (file)
--- a/src/lxc/lxccontainer.c
+++ b/src/lxc/lxccontainer.c
@@ -976,7 +976,7 @@ struct lxc_container *lxc_container_new(const char *name)
        c->set_cgroup_item = lxcapi_set_cgroup_item;
 
        /* we'll allow the caller to update these later */
-       if (lxc_log_init(NULL, NULL, "lxc_container", 0)) {
+       if (lxc_log_init(NULL, "none", NULL, "lxc_container", 0)) {
                fprintf(stderr, "failed to open log\n");
                goto err;
        }