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-rw-r--r--time/zdump.c331
1 files changed, 331 insertions, 0 deletions
diff --git a/time/zdump.c b/time/zdump.c
new file mode 100644
index 0000000000..d35df33073
--- /dev/null
+++ b/time/zdump.c
@@ -0,0 +1,331 @@
+#ifndef lint
+#ifndef NOID
+static char elsieid[] = "@(#)zdump.c 7.12";
+#endif /* !defined NOID */
+#endif /* !defined lint */
+
+/*
+** This code has been made independent of the rest of the time
+** conversion package to increase confidence in the verification it provides.
+** You can use this code to help in verifying other implementations.
+*/
+
+#include "stdio.h" /* for stdout, stderr */
+#include "string.h" /* for strcpy */
+#include "sys/types.h" /* for time_t */
+#include "time.h" /* for struct tm */
+
+#ifndef MAX_STRING_LENGTH
+#define MAX_STRING_LENGTH 1024
+#endif /* !defined MAX_STRING_LENGTH */
+
+#ifndef TRUE
+#define TRUE 1
+#endif /* !defined TRUE */
+
+#ifndef FALSE
+#define FALSE 0
+#endif /* !defined FALSE */
+
+#ifndef EXIT_SUCCESS
+#define EXIT_SUCCESS 0
+#endif /* !defined EXIT_SUCCESS */
+
+#ifndef EXIT_FAILURE
+#define EXIT_FAILURE 1
+#endif /* !defined EXIT_FAILURE */
+
+#ifndef SECSPERMIN
+#define SECSPERMIN 60
+#endif /* !defined SECSPERMIN */
+
+#ifndef MINSPERHOUR
+#define MINSPERHOUR 60
+#endif /* !defined MINSPERHOUR */
+
+#ifndef SECSPERHOUR
+#define SECSPERHOUR (SECSPERMIN * MINSPERHOUR)
+#endif /* !defined SECSPERHOUR */
+
+#ifndef HOURSPERDAY
+#define HOURSPERDAY 24
+#endif /* !defined HOURSPERDAY */
+
+#ifndef EPOCH_YEAR
+#define EPOCH_YEAR 1970
+#endif /* !defined EPOCH_YEAR */
+
+#ifndef TM_YEAR_BASE
+#define TM_YEAR_BASE 1900
+#endif /* !defined TM_YEAR_BASE */
+
+#ifndef DAYSPERNYEAR
+#define DAYSPERNYEAR 365
+#endif /* !defined DAYSPERNYEAR */
+
+#ifndef isleap
+#define isleap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)
+#endif /* !defined isleap */
+
+#ifndef GNUC_or_lint
+#ifdef lint
+#define GNUC_or_lint
+#endif /* defined lint */
+#ifdef __GNUC__
+#define GNUC_or_lint
+#endif /* defined __GNUC__ */
+#endif /* !defined GNUC_or_lint */
+
+#ifndef INITIALIZE
+#ifdef GNUC_or_lint
+#define INITIALIZE(x) ((x) = 0)
+#endif /* defined GNUC_or_lint */
+#ifndef GNUC_or_lint
+#define INITIALIZE(x)
+#endif /* !defined GNUC_or_lint */
+#endif /* !defined INITIALIZE */
+
+extern char ** environ;
+extern int getopt();
+extern char * optarg;
+extern int optind;
+extern time_t time();
+extern char * tzname[2];
+
+#ifdef USG
+extern void exit();
+extern void perror();
+#endif /* defined USG */
+
+static char * abbr();
+static long delta();
+static time_t hunt();
+static int longest;
+static char * progname;
+static void show();
+
+int
+main(argc, argv)
+int argc;
+char * argv[];
+{
+ register int i, c;
+ register int vflag;
+ register char * cutoff;
+ register int cutyear;
+ register long cuttime;
+ char ** fakeenv;
+ time_t now;
+ time_t t, newt;
+ time_t hibit;
+ struct tm tm, newtm;
+
+ INITIALIZE(cuttime);
+ progname = argv[0];
+ vflag = 0;
+ cutoff = NULL;
+ while ((c = getopt(argc, argv, "c:v")) == 'c' || c == 'v')
+ if (c == 'v')
+ vflag = 1;
+ else cutoff = optarg;
+ if (c != EOF ||
+ (optind == argc - 1 && strcmp(argv[optind], "=") == 0)) {
+ (void) fprintf(stderr,
+"%s: usage is %s [ -v ] [ -c cutoff ] zonename ...\n",
+ argv[0], argv[0]);
+ (void) exit(EXIT_FAILURE);
+ }
+ if (cutoff != NULL) {
+ int y;
+
+ cutyear = atoi(cutoff);
+ cuttime = 0;
+ for (y = EPOCH_YEAR; y < cutyear; ++y)
+ cuttime += DAYSPERNYEAR + isleap(y);
+ cuttime *= SECSPERHOUR * HOURSPERDAY;
+ }
+ (void) time(&now);
+ longest = 0;
+ for (i = optind; i < argc; ++i)
+ if (strlen(argv[i]) > longest)
+ longest = strlen(argv[i]);
+ for (hibit = 1; (hibit << 1) != 0; hibit <<= 1)
+ continue;
+ {
+ register int from, to;
+
+ for (i = 0; environ[i] != NULL; ++i)
+ continue;
+ fakeenv = (char **) malloc((i + 2) * sizeof *fakeenv);
+ if (fakeenv == NULL ||
+ (fakeenv[0] = (char *) malloc(longest + 4)) == NULL) {
+ (void) perror(progname);
+ (void) exit(EXIT_FAILURE);
+ }
+ to = 0;
+ (void) strcpy(fakeenv[to++], "TZ=");
+ for (from = 0; environ[from] != NULL; ++from)
+ if (strncmp(environ[from], "TZ=", 3) != 0)
+ fakeenv[to++] = environ[from];
+ fakeenv[to] = NULL;
+ environ = fakeenv;
+ }
+ for (i = optind; i < argc; ++i) {
+ static char buf[MAX_STRING_LENGTH];
+
+ (void) strcpy(&fakeenv[0][3], argv[i]);
+ show(argv[i], now, FALSE);
+ if (!vflag)
+ continue;
+ /*
+ ** Get lowest value of t.
+ */
+ t = hibit;
+ if (t > 0) /* time_t is unsigned */
+ t = 0;
+ show(argv[i], t, TRUE);
+ t += SECSPERHOUR * HOURSPERDAY;
+ show(argv[i], t, TRUE);
+ tm = *localtime(&t);
+ (void) strncpy(buf, abbr(&tm), (sizeof buf) - 1);
+ for ( ; ; ) {
+ if (cutoff != NULL && t >= cuttime)
+ break;
+ newt = t + SECSPERHOUR * 12;
+ if (cutoff != NULL && newt >= cuttime)
+ break;
+ if (newt <= t)
+ break;
+ newtm = *localtime(&newt);
+ if (delta(&newtm, &tm) != (newt - t) ||
+ newtm.tm_isdst != tm.tm_isdst ||
+ strcmp(abbr(&newtm), buf) != 0) {
+ newt = hunt(argv[i], t, newt);
+ newtm = *localtime(&newt);
+ (void) strncpy(buf, abbr(&newtm),
+ (sizeof buf) - 1);
+ }
+ t = newt;
+ tm = newtm;
+ }
+ /*
+ ** Get highest value of t.
+ */
+ t = ~((time_t) 0);
+ if (t < 0) /* time_t is signed */
+ t &= ~hibit;
+ t -= SECSPERHOUR * HOURSPERDAY;
+ show(argv[i], t, TRUE);
+ t += SECSPERHOUR * HOURSPERDAY;
+ show(argv[i], t, TRUE);
+ }
+ if (fflush(stdout) || ferror(stdout)) {
+ (void) fprintf(stderr, "%s: Error writing standard output ",
+ argv[0]);
+ (void) perror("standard output");
+ (void) exit(EXIT_FAILURE);
+ }
+ exit(EXIT_SUCCESS);
+
+ /* gcc -Wall pacifier */
+ for ( ; ; )
+ continue;
+}
+
+static time_t
+hunt(name, lot, hit)
+char * name;
+time_t lot;
+time_t hit;
+{
+ time_t t;
+ struct tm lotm;
+ struct tm tm;
+ static char loab[MAX_STRING_LENGTH];
+
+ lotm = *localtime(&lot);
+ (void) strncpy(loab, abbr(&lotm), (sizeof loab) - 1);
+ while ((hit - lot) >= 2) {
+ t = lot / 2 + hit / 2;
+ if (t <= lot)
+ ++t;
+ else if (t >= hit)
+ --t;
+ tm = *localtime(&t);
+ if (delta(&tm, &lotm) == (t - lot) &&
+ tm.tm_isdst == lotm.tm_isdst &&
+ strcmp(abbr(&tm), loab) == 0) {
+ lot = t;
+ lotm = tm;
+ } else hit = t;
+ }
+ show(name, lot, TRUE);
+ show(name, hit, TRUE);
+ return hit;
+}
+
+/*
+** Thanks to Paul Eggert (eggert@twinsun.com) for logic used in delta.
+*/
+
+static long
+delta(newp, oldp)
+struct tm * newp;
+struct tm * oldp;
+{
+ long result;
+ int tmy;
+
+ if (newp->tm_year < oldp->tm_year)
+ return -delta(oldp, newp);
+ result = 0;
+ for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy)
+ result += DAYSPERNYEAR + isleap(tmy + TM_YEAR_BASE);
+ result += newp->tm_yday - oldp->tm_yday;
+ result *= HOURSPERDAY;
+ result += newp->tm_hour - oldp->tm_hour;
+ result *= MINSPERHOUR;
+ result += newp->tm_min - oldp->tm_min;
+ result *= SECSPERMIN;
+ result += newp->tm_sec - oldp->tm_sec;
+ return result;
+}
+
+extern struct tm * localtime();
+
+static void
+show(zone, t, v)
+char * zone;
+time_t t;
+int v;
+{
+ struct tm * tmp;
+
+ (void) printf("%-*s ", longest, zone);
+ if (v)
+ (void) printf("%.24s GMT = ", asctime(gmtime(&t)));
+ tmp = localtime(&t);
+ (void) printf("%.24s", asctime(tmp));
+ if (*abbr(tmp) != '\0')
+ (void) printf(" %s", abbr(tmp));
+ if (v) {
+ (void) printf(" isdst=%d", tmp->tm_isdst);
+#ifdef TM_GMTOFF
+ (void) printf(" gmtoff=%ld", tmp->TM_GMTOFF);
+#endif /* defined TM_GMTOFF */
+ }
+ (void) printf("\n");
+}
+
+static char *
+abbr(tmp)
+struct tm * tmp;
+{
+ register char * result;
+ static char nada;
+
+ if (tmp->tm_isdst != 0 && tmp->tm_isdst != 1)
+ return &nada;
+ result = tzname[tmp->tm_isdst];
+ return (result == NULL) ? &nada : result;
+}