--- /dev/null
+/*
+ * parse time string - user friendly date and time parser
+ * Copyright © 2012 Jani Nikula
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Jani Nikula <jani@nikula.org>
+ */
+
+#include <assert.h>
+#include <ctype.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "parse-time-string.h"
+
+#define ARRAY_SIZE(a) (sizeof (a) / sizeof (a[0]))
+
+static const char *parse_time_error_strings[] = {
+ [PARSE_TIME_OK] = "OK",
+ [PARSE_TIME_ERR] = "ERR",
+ [PARSE_TIME_ERR_LIB] = "LIB",
+ [PARSE_TIME_ERR_ALREADYSET] = "ALREADYSET",
+ [PARSE_TIME_ERR_FORMAT] = "FORMAT",
+ [PARSE_TIME_ERR_DATEFORMAT] = "DATEFORMAT",
+ [PARSE_TIME_ERR_TIMEFORMAT] = "TIMEFORMAT",
+ [PARSE_TIME_ERR_INVALIDDATE] = "INVALIDDATE",
+ [PARSE_TIME_ERR_INVALIDTIME] = "INVALIDTIME",
+ [PARSE_TIME_ERR_KEYWORD] = "KEYWORD",
+};
+
+static const char *
+parse_time_strerror (unsigned int errnum)
+{
+ if (errnum < ARRAY_SIZE (parse_time_error_strings))
+ return parse_time_error_strings[errnum];
+ else
+ return NULL;
+}
+
+/*
+ * concat argv[start]...argv[end - 1], separating them by a single
+ * space, to a malloced string
+ */
+static char *
+concat_args (int start, int end, char *argv[])
+{
+ int i;
+ size_t len = 1;
+ char *p;
+
+ for (i = start; i < end; i++)
+ len += strlen (argv[i]) + 1;
+
+ p = malloc (len);
+ if (!p)
+ return NULL;
+
+ *p = 0;
+
+ for (i = start; i < end; i++) {
+ if (i != start)
+ strcat (p, " ");
+ strcat (p, argv[i]);
+ }
+
+ return p;
+}
+
+#define DEFAULT_FORMAT "%a %b %d %T %z %Y"
+
+static void
+usage (const char *name)
+{
+ printf ("Usage: %s [options ...] [<date/time>]\n\n", name);
+ printf (
+ "Parse <date/time> and display it in given format. If <date/time> is\n"
+ "not given, parse each line in stdin according to:\n\n"
+ " <date/time> [(==>|==_>|==^>|==^^>)<ignored>] [#<comment>]\n\n"
+ "and produce output:\n\n"
+ " <date/time> (==>|==_>|==^>|==^^>) <time in --format=FMT> [#<comment>]\n\n"
+ "preserving whitespace and comment in input. The operators ==>, ==_>,\n"
+ "==^>, and ==^^> define rounding as no rounding, round down, round up\n"
+ "inclusive, and round up, respectively.\n\n"
+
+ " -f, --format=FMT output format, FMT according to strftime(3)\n"
+ " (default: \"%s\")\n"
+ " -r, --ref=N use N seconds since epoch as reference time\n"
+ " (default: now)\n"
+ " -u, --^ round result up inclusive (default: no rounding)\n"
+ " -U, --^^ round result up (default: no rounding)\n"
+ " -d, --_ round result down (default: no rounding)\n"
+ " -h, --help print this help\n",
+ DEFAULT_FORMAT);
+}
+
+struct {
+ const char *operator;
+ int round;
+} operators[] = {
+ { "==>", PARSE_TIME_NO_ROUND },
+ { "==_>", PARSE_TIME_ROUND_DOWN },
+ { "==^>", PARSE_TIME_ROUND_UP_INCLUSIVE },
+ { "==^^>", PARSE_TIME_ROUND_UP },
+};
+
+static const char *
+find_operator_in_string (char *str, char **ptr, int *round)
+{
+ const char *oper = NULL;
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE (operators); i++) {
+ char *p = strstr (str, operators[i].operator);
+ if (p) {
+ if (round)
+ *round = operators[i].round;
+ if (ptr)
+ *ptr = p;
+
+ oper = operators[i].operator;
+ break;
+ }
+ }
+
+ return oper;
+}
+
+static const char *
+get_operator (int round)
+{
+ const char *oper = NULL;
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(operators); i++) {
+ if (round == operators[i].round) {
+ oper = operators[i].operator;
+ break;
+ }
+ }
+
+ return oper;
+}
+
+static int
+parse_stdin (FILE *infile, time_t *ref, int round, const char *format)
+{
+ char *input = NULL;
+ char result[1024];
+ size_t inputsize;
+ ssize_t len;
+ struct tm tm;
+ time_t t;
+ int r;
+
+ while ((len = getline (&input, &inputsize, infile)) != -1) {
+ const char *oper;
+ char *trail, *tmp;
+
+ /* trail is trailing whitespace and (optional) comment */
+ trail = strchr (input, '#');
+ if (!trail)
+ trail = input + len;
+
+ while (trail > input && isspace ((unsigned char) *(trail-1)))
+ trail--;
+
+ if (trail == input) {
+ printf ("%s", input);
+ continue;
+ }
+
+ tmp = strdup (trail);
+ if (!tmp) {
+ fprintf (stderr, "strdup() failed\n");
+ continue;
+ }
+ *trail = '\0';
+ trail = tmp;
+
+ /* operator */
+ oper = find_operator_in_string (input, &tmp, &round);
+ if (oper) {
+ *tmp = '\0';
+ } else {
+ oper = get_operator (round);
+ assert (oper);
+ }
+
+ r = parse_time_string (input, &t, ref, round);
+ if (!r) {
+ if (!localtime_r (&t, &tm)) {
+ fprintf (stderr, "localtime_r() failed\n");
+ free (trail);
+ continue;
+ }
+
+ strftime (result, sizeof (result), format, &tm);
+ } else {
+ const char *errstr = parse_time_strerror (r);
+ if (errstr)
+ snprintf (result, sizeof (result), "ERROR: %s", errstr);
+ else
+ snprintf (result, sizeof (result), "ERROR: %d", r);
+ }
+
+ printf ("%s%s %s%s", input, oper, result, trail);
+ free (trail);
+ }
+
+ free (input);
+
+ return 0;
+}
+
+int
+main (int argc, char *argv[])
+{
+ int r;
+ struct tm tm;
+ time_t result;
+ time_t now;
+ time_t *nowp = NULL;
+ char *argstr;
+ int round = PARSE_TIME_NO_ROUND;
+ char buf[1024];
+ const char *format = DEFAULT_FORMAT;
+ struct option options[] = {
+ { "help", no_argument, NULL, 'h' },
+ { "^", no_argument, NULL, 'u' },
+ { "^^", no_argument, NULL, 'U' },
+ { "_", no_argument, NULL, 'd' },
+ { "format", required_argument, NULL, 'f' },
+ { "ref", required_argument, NULL, 'r' },
+ { NULL, 0, NULL, 0 },
+ };
+
+ for (;;) {
+ int c;
+
+ c = getopt_long (argc, argv, "huUdf:r:", options, NULL);
+ if (c == -1)
+ break;
+
+ switch (c) {
+ case 'f':
+ /* output format */
+ format = optarg;
+ break;
+ case 'u':
+ round = PARSE_TIME_ROUND_UP_INCLUSIVE;
+ break;
+ case 'U':
+ round = PARSE_TIME_ROUND_UP;
+ break;
+ case 'd':
+ round = PARSE_TIME_ROUND_DOWN;
+ break;
+ case 'r':
+ /* specify now in seconds since epoch */
+ now = (time_t) strtol (optarg, NULL, 10);
+ if (now >= (time_t) 0)
+ nowp = &now;
+ break;
+ case 'h':
+ case '?':
+ default:
+ usage (argv[0]);
+ return 1;
+ }
+ }
+
+ if (optind == argc)
+ return parse_stdin (stdin, nowp, round, format);
+
+ argstr = concat_args (optind, argc, argv);
+ if (!argstr)
+ return 1;
+
+ r = parse_time_string (argstr, &result, nowp, round);
+
+ free (argstr);
+
+ if (r) {
+ const char *errstr = parse_time_strerror (r);
+ if (errstr)
+ fprintf (stderr, "ERROR: %s\n", errstr);
+ else
+ fprintf (stderr, "ERROR: %d\n", r);
+
+ return r;
+ }
+
+ if (!localtime_r (&result, &tm))
+ return 1;
+
+ strftime (buf, sizeof (buf), format, &tm);
+ printf ("%s\n", buf);
+
+ return 0;
+}
projects / notmuch.git / commitdiff