localtime and ctime are not MT-SAFE

There are a number of nit-level issues throughout the source with
the use of localtime and ctime. While they apparently aren't causing
too many problems, apart from the one in bz 828058, they ought to be
fixed. Among the "real" problems that are fixed in this patch:
1) general localtime and ctime not MT-SAFE. There's a non-zero chance
   that another thread calling localtime (or ctime) will over-write
   the static data about to be used in another thread
2) localtime(& <64-bit-type>) or ctime(& <64-bit-type>) generally
   not a problem on 64-bit or little-endian 32-bit. But even though
   we probably have zero users on big-ending 32-bit platforms, it's
   still incorrect.
3) multiple nested calls passed as params. Last one wins, i.e. over-
   writes result of prior calls.
4) Inconsistent error handling. Most of these calls are for logging,
   tracing, or dumping. I submit that if an error somehow occurs in
   the call to localtime or ctime, the log/trace/dump still should
   still occur.
5) Appliances should all have their clocks set to UTC, and all log
   entries, traces, and dumps should use GMT.
6) fix strtok(), change to strtok_r()

Other things this patch fixes/changes (that aren't bugs per se):
1) Change "%Y-%m-%d %H:%M:%S" and similar to their equivalent shorthand,
   e.g. "%F %T"
2) change sizeof(timestr) to sizeof timestr. sizeof is an operator,
   not a function. You don't use i +(32), why use sizeof(<var>).
   (And yes, you do use parens with sizeof(<type>).)
3) change 'char timestr[256]' to 'char timestr[32]' where appropriate.
   Per-thread stack is limited. Time strings are never longer than ~20
   characters, so why waste 220+ bytes on the stack?

Things this patch doesn't fix:
1) hodgepodge of %Y-%m-%d %H:%M:%S versus %Y/%m/%d-%H%M%S and other
   variations. It's not clear to me whether this ever matters, not to
   mention 3rd party log filtering tools may already rely on a
   particular format. Still it would be nice to have a single manifest
   constant and have every call to localtime/strftime consistently use
   the same format.

BUG: 832173

Change-Id: Iee9719db4576eacc6c75694d9107954d0912cba8
Signed-off-by: Kaleb S. KEITHLEY <kkeithle@redhat.com>
Reviewed-on: http://review.gluster.org/3613
Reviewed-by: Anand Avati <avati@redhat.com>
Tested-by: Anand Avati <avati@redhat.com>

1 files changed, 13 insertions, 17 deletions

diff --git a/glusterfsd/src/glusterfsd.c b/glusterfsd/src/glusterfsd.c
index 0e9ff2ccc7f..51f0a30c9a9 100644
--- a/glusterfsd/src/glusterfsd.c
+++ b/glusterfsd/src/glusterfsd.c
@@ -917,7 +917,6 @@ generate_uuid ()
         char           tmp_str[1024] = {0,};
         char           hostname[256] = {0,};
         struct timeval tv = {0,};
-        struct tm      now = {0, };
         char           now_str[32];
 
         if (gettimeofday (&tv, NULL) == -1) {
@@ -926,15 +925,14 @@ generate_uuid ()
                         strerror (errno));
         }
 
-        if (gethostname (hostname, 256) == -1) {
+        if (gethostname (hostname, sizeof hostname) == -1) {
                 gf_log ("glusterfsd", GF_LOG_ERROR,
                         "gethostname: failed %s",
                         strerror (errno));
         }
 
-        localtime_r (&tv.tv_sec, &now);
-        strftime (now_str, 32, "%Y/%m/%d-%H:%M:%S", &now);
-        snprintf (tmp_str, 1024, "%s-%d-%s:%" GF_PRI_SUSECONDS,
+        gf_time_fmt (now_str, sizeof now_str, tv.tv_sec, gf_timefmt_Ymd_T);
+        snprintf (tmp_str, sizeof tmp_str, "%s-%d-%s:%" GF_PRI_SUSECONDS,
                   hostname, getpid(), now_str, tv.tv_usec);
 
         return gf_strdup (tmp_str);
@@ -1176,16 +1174,14 @@ gf_check_and_set_mem_acct (int argc, char *argv[], glusterfs_ctx_t *ctx)
 int
 parse_cmdline (int argc, char *argv[], glusterfs_ctx_t *ctx)
 {
-        int               process_mode = 0;
-        int               ret = 0;
-        struct stat       stbuf = {0, };
-        struct tm        *tm = NULL;
-        time_t            utime;
-        char              timestr[256];
-        char              tmp_logfile[1024] = { 0 };
-        char              *tmp_logfile_dyn = NULL;
-        char              *tmp_logfilebase = NULL;
-        cmd_args_t        *cmd_args = NULL;
+        int          process_mode = 0;
+        int          ret = 0;
+        struct stat  stbuf = {0, };
+        char         timestr[32];
+        char         tmp_logfile[1024] = { 0 };
+        char        *tmp_logfile_dyn = NULL;
+        char        *tmp_logfilebase = NULL;
+        cmd_args_t  *cmd_args = NULL;
 
         cmd_args = &ctx->cmd_args;
 
@@ -1242,8 +1238,8 @@ parse_cmdline (int argc, char *argv[], glusterfs_ctx_t *ctx)
                      (S_ISREG (stbuf.st_mode) || S_ISLNK (stbuf.st_mode))) ||
                     (ret == -1)) {
                         /* Have separate logfile per run */
-                        tm = localtime (&utime);
-                        strftime (timestr, 256, "%Y%m%d.%H%M%S", tm);
+                        gf_time_fmt (timestr, sizeof timestr, time (NULL),
+                                     gf_timefmt_FT);
                         sprintf (tmp_logfile, "%s.%s.%d",
                                  cmd_args->log_file, timestr, getpid ());