last: add --since time spec option

The --since and --until options are companions often needed together.

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

diff --git a/login-utils/last.c b/login-utils/last.c
index 410e612107860a713b7b39628ccc80ff66a31a9f..e5a9c243297dc2ba7cce44bb8e540c91f0779d2f 100644 (file)
--- a/login-utils/last.c
+++ b/login-utils/last.c
@@ -426,8 +426,9 @@ static void __attribute__((__noreturn__)) usage(FILE *out)
        fputs(_(" -i, --ip             display IP numbers in numbers-and-dots notation\n"), out);
        fputs(_(" -n, --limit <number> how many lines to show\n"), out);
        fputs(_(" -R, --nohostname     don't display the hostname field\n"), out);
-       fputs(_(" -t, --until <YYYYMMDDHHMMSS>  display the state of the specified time\n"), out);
-       fputs(_(" -p, --present <YYYYMMDDHHMMSS>  display who where present at the specified time\n"), out);
+       fputs(_(" -s, --since <time>   display the lines since the specified time\n"), out);
+       fputs(_(" -t, --until <time>   display the lines until the specified time\n"), out);
+       fputs(_(" -p, --present <time> display who where present at the specified time\n"), out);
        fputs(_(" -w, --fullnames      display full user and domain names\n"), out);
        fputs(_(" -x, --system         display system shutdown entries and run level changes\n"), out);
 
@@ -441,7 +442,7 @@ static void __attribute__((__noreturn__)) usage(FILE *out)
 
 
 static void process_wtmp_file(char *ufile, int lastb, int extended,
-                             time_t until, time_t present)
+                             time_t since, time_t until, time_t present)
 {
        FILE *fp;               /* Filepointer of wtmp file */
 
@@ -510,6 +511,9 @@ static void process_wtmp_file(char *ufile, int lastb, int extended,
                if (uread(fp, &ut, &quit) != 1)
                        break;
 
+               if (since && ut.ut_time < since)
+                       continue;
+
                if (until && until < ut.ut_time)
                        continue;
 
@@ -695,7 +699,8 @@ int main(int argc, char **argv)
        int lastb = 0;          /* Is this 'lastb' ? */
        int extended = 0;       /* Lots of info. */
 
-       time_t until = 0;       /* at what time to stop parsing the file */
+       time_t since = 0;       /* at what time to start displaying the file */
+       time_t until = 0;       /* at what time to stop displaying the file */
        time_t present = 0;     /* who where present at time_t */
        usec_t p;
 
@@ -706,6 +711,7 @@ int main(int argc, char **argv)
              { "nohostname", no_argument,       NULL, 'R' },
              { "version",    no_argument,       NULL, 'V' },
              { "hostlast",   no_argument,       NULL, 'a' },
+             { "since",      required_argument, NULL, 's' },
              { "until",      required_argument, NULL, 't' },
              { "present",    required_argument, NULL, 'p' },
              { "system",     no_argument,       NULL, 'x' },
@@ -722,7 +728,7 @@ int main(int argc, char **argv)
        atexit(close_stdout);
 
        while ((c = getopt_long(argc, argv,
-                       "hVf:n:RxadFit:p:0123456789w", long_opts, NULL)) != -1) {
+                       "hVf:n:RxadFit:p:s:0123456789w", long_opts, NULL)) != -1) {
                switch(c) {
                case 'h':
                        usage(stdout);
@@ -761,6 +767,14 @@ int main(int argc, char **argv)
                                errx(EXIT_FAILURE, _("invalid time value \"%s\""), optarg);
                        present = (time_t) (p / 1000000);
                        break;
+               case 's':
+                       since = parsetm(optarg);
+                       if (since != (time_t) -1)
+                               break;
+                       if (parse_timestamp(optarg, &p) < 0)
+                               errx(EXIT_FAILURE, _("invalid time value \"%s\""), optarg);
+                       since = (time_t) (p / 1000000);
+                       break;
                case 't':
                        if (parse_timestamp(optarg, &p) < 0)
                                errx(EXIT_FAILURE, _("invalid time value \"%s\""), optarg);
@@ -799,7 +813,7 @@ int main(int argc, char **argv)
        }
 
        for (i = 0; i < altc; i++) {
-               process_wtmp_file(altv[i], lastb, extended, until, present);
+               process_wtmp_file(altv[i], lastb, extended, since, until, present);
                free(altv[i]);
        }
        free(altv);