utmpdump: use iso-8601 timestamp format with subsecond accuracy

Newer 'struct utmp' is using 'struct timeval' to represent login and logout
times, so include the maximum accuracy to textual utmp format.  Notice that
this change does not remove support of converting earlier textual formats
back to binary.  But conversions from binary to former format will no longer
be available.

Signed-off-by: Sami Kerola <kerolasa@iki.fi>

diff --git a/login-utils/Makemodule.am b/login-utils/Makemodule.am
index 502ecd5034d3dcd06a25741ffb7c53fb0bff0aca..be07ace43f4fa4d0aff4bc75862c4a45cf271c61 100644 (file)
--- a/login-utils/Makemodule.am
+++ b/login-utils/Makemodule.am
@@ -67,6 +67,7 @@ if BUILD_UTMPDUMP
 usrbin_exec_PROGRAMS += utmpdump
 dist_man_MANS += login-utils/utmpdump.1
 utmpdump_SOURCES = login-utils/utmpdump.c
+utmpdump_LDADD = $(LDADD) libcommon.la
 endif
 
 

diff --git a/login-utils/utmpdump.c b/login-utils/utmpdump.c
index 6eaf202bdebaac426993272c4c4f49150738da2c..1849a4e931c7119a591b2e1461e5d019c7091175 100644 (file)
--- a/login-utils/utmpdump.c
+++ b/login-utils/utmpdump.c
@@ -42,22 +42,10 @@
 
 #include "c.h"
 #include "nls.h"
+#include "timeutils.h"
 #include "xalloc.h"
 #include "closestream.h"
 
-static char *timetostr(const time_t time)
-{
-       static char s[29];      /* [Tue Sep 01 00:00:00 1998 GMT] */
-       struct tm *tmp;
-
-       if (time != 0 && (tmp = gmtime(&time)))
-               strftime(s, 29, "%a %b %d %T %Y %Z", tmp);
-       else
-               s[0] = '\0';
-
-       return s;
-}
-
 static time_t strtotime(const char *s_time)
 {
        struct tm tm;
@@ -67,15 +55,32 @@ static time_t strtotime(const char *s_time)
        if (s_time[0] == ' ' || s_time[0] == '\0')
                return (time_t)0;
 
-       strptime(s_time, "%a %b %d %T %Y", &tm);
-
-       /* Cheesy way of checking for DST */
-       if (s_time[26] == 'D')
-               tm.tm_isdst = 1;
-
+       if (isdigit(s_time[0])) {
+               /* [1998-09-01T01:00:00,000000+00:00]
+                * Subseconds are parsed with strtousec().  Timezone is
+                * always UTC-0 */
+               strptime(s_time, "%Y-%m-%dT%H:%M:%S", &tm);
+       } else {
+               /* [Tue Sep 01 00:00:00 1998 GMT] */
+               strptime(s_time, "%a %b %d %T %Y", &tm);
+               /* Cheesy way of checking for DST.  This could be needed
+                * with legacy dumps that used localtime(3).  */
+               if (s_time[26] == 'D')
+                       tm.tm_isdst = 1;
+       }
        return timegm(&tm);
 }
 
+#if defined(_HAVE_UT_TV)
+static suseconds_t strtousec(const char *s_time)
+{
+       const char *s = strchr(s_time, ',');
+       if (s)
+               return (suseconds_t) atoi(s + 1);
+       return 0;
+}
+#endif
+
 #define cleanse(x) xcleanse(x, sizeof(x))
 static void xcleanse(char *s, int len)
 {
@@ -86,26 +91,31 @@ static void xcleanse(char *s, int len)
 
 static void print_utline(struct utmp *ut, FILE *out)
 {
-       const char *addr_string, *time_string;
+       const char *addr_string;
        char buffer[INET6_ADDRSTRLEN];
+       char time_string[40];
+       struct timeval tv;
 
        if (ut->ut_addr_v6[1] || ut->ut_addr_v6[2] || ut->ut_addr_v6[3])
                addr_string = inet_ntop(AF_INET6, &(ut->ut_addr_v6), buffer, sizeof(buffer));
        else
                addr_string = inet_ntop(AF_INET, &(ut->ut_addr_v6), buffer, sizeof(buffer));
 
-#if defined(_HAVE_UT_TV)
-       time_string = timetostr(ut->ut_tv.tv_sec);
-#else
-       time_string = timetostr((time_t)ut->ut_time);   /* ut_time is not always a time_t */
-#endif
+       tv.tv_sec = ut->ut_tv.tv_sec;
+       tv.tv_usec = ut->ut_tv.tv_usec;
+
+       if (strtimeval_iso(&tv,
+                          ISO_8601_DATE | ISO_8601_TIME | ISO_8601_COMMAUSEC |
+                          ISO_8601_TIMEZONE | ISO_8601_GMTIME, time_string,
+                          sizeof(time_string)) != 0)
+               return;
        cleanse(ut->ut_id);
        cleanse(ut->ut_user);
        cleanse(ut->ut_line);
        cleanse(ut->ut_host);
 
        /*            pid    id       user     line     host     addr       time */
-       fprintf(out, "[%d] [%05d] [%-4.4s] [%-*.*s] [%-*.*s] [%-*.*s] [%-15s] [%-28.28s]\n",
+       fprintf(out, "[%d] [%05d] [%-4.4s] [%-*.*s] [%-*.*s] [%-*.*s] [%-15s] [%s]\n",
               ut->ut_type, ut->ut_pid, ut->ut_id, 8, UT_NAMESIZE, ut->ut_user,
               12, UT_LINESIZE, ut->ut_line, 20, UT_HOSTSIZE, ut->ut_host,
               addr_string, time_string);
@@ -279,6 +289,7 @@ static void undump(FILE *in, FILE *out)
                        inet_pton(AF_INET6, s_addr, &(ut.ut_addr_v6));
 #if defined(_HAVE_UT_TV)
                ut.ut_tv.tv_sec = strtotime(s_time);
+               ut.ut_tv.tv_usec = strtousec(s_time);
 #else
                ut.ut_time = strtotime(s_time);
 #endif