diff options
Diffstat (limited to 'lib/libc/tests/stdtime/detect_tz_changes_test.c')
| -rw-r--r-- | lib/libc/tests/stdtime/detect_tz_changes_test.c | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/lib/libc/tests/stdtime/detect_tz_changes_test.c b/lib/libc/tests/stdtime/detect_tz_changes_test.c new file mode 100644 index 000000000000..9722546747fd --- /dev/null +++ b/lib/libc/tests/stdtime/detect_tz_changes_test.c @@ -0,0 +1,281 @@ +/*- + * Copyright (c) 2025 Klara, Inc. + * + * SPDX-License-Identifier: BSD-2-Clause + */ + +#include <sys/stat.h> +#include <sys/wait.h> + +#include <dlfcn.h> +#include <fcntl.h> +#include <limits.h> +#include <poll.h> +#include <stdarg.h> +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <time.h> +#include <unistd.h> + +#include <atf-c.h> + +static const time_t then = 1751328000; /* 2025-07-01 00:00:00 UTC */ +static const char *tz_change_interval_sym = "__tz_change_interval"; +static int *tz_change_interval_p; +static const int tz_change_interval = 3; +static int tz_change_timeout = 90; + +static bool debugging; + +static void +debug(const char *fmt, ...) +{ + va_list ap; + + if (debugging) { + va_start(ap, fmt); + vfprintf(stderr, fmt, ap); + va_end(ap); + fputc('\n', stderr); + } +} + +static void +change_tz(const char *tzn) +{ + static const char *zfn = "/usr/share/zoneinfo"; + static const char *tfn = "root/etc/.localtime"; + static const char *dfn = "root/etc/localtime"; + ssize_t clen; + int zfd, sfd, dfd; + + ATF_REQUIRE((zfd = open(zfn, O_DIRECTORY | O_SEARCH)) >= 0); + ATF_REQUIRE((sfd = openat(zfd, tzn, O_RDONLY)) >= 0); + ATF_REQUIRE((dfd = open(tfn, O_CREAT | O_TRUNC | O_WRONLY)) >= 0); + do { + clen = copy_file_range(sfd, NULL, dfd, NULL, SSIZE_MAX, 0); + ATF_REQUIRE_MSG(clen != -1, "failed to copy %s/%s: %m", + zfn, tzn); + } while (clen > 0); + ATF_CHECK_EQ(0, close(dfd)); + ATF_CHECK_EQ(0, close(sfd)); + ATF_CHECK_EQ(0, close(zfd)); + ATF_REQUIRE_EQ(0, rename(tfn, dfn)); + debug("time zone %s installed", tzn); +} + +/* + * Test time zone change detection. + * + * The parent creates a chroot containing only /etc/localtime, initially + * set to UTC. It then forks a child which enters the chroot, repeatedly + * checks the current time zone, and prints it to stdout if it changes + * (including once on startup). Meanwhile, the parent waits for output + * from the child. Every time it receives a line of text from the child, + * it checks that it is as expected, then changes /etc/localtime within + * the chroot to the next case in the list. Once it reaches the end of + * the list, it closes a pipe to notify the child, which terminates. + * + * Note that ATF and / or Kyua may have set the timezone before the test + * case starts (even unintentionally). Therefore, we start the test only + * after we've received and discarded the first report from the child, + * which should come almost immediately on startup. + */ +ATF_TC(detect_tz_changes); +ATF_TC_HEAD(detect_tz_changes, tc) +{ + atf_tc_set_md_var(tc, "descr", "Test timezone change detection"); + atf_tc_set_md_var(tc, "require.user", "root"); + atf_tc_set_md_var(tc, "timeout", "600"); +} +ATF_TC_BODY(detect_tz_changes, tc) +{ + static const struct tzcase { + const char *tzfn; + const char *expect; + } tzcases[] = { + /* + * A handful of time zones and the expected result of + * strftime("%z (%Z)", tm) when that time zone is active + * and tm represents a date in the summer of 2025. + */ + { "America/Vancouver", "-0700 (PDT)" }, + { "America/New_York", "-0400 (EDT)" }, + { "Europe/London", "+0100 (BST)" }, + { "Europe/Paris", "+0200 (CEST)" }, + { "Asia/Kolkata", "+0530 (IST)" }, + { "Asia/Tokyo", "+0900 (JST)" }, + { "Australia/Canberra", "+1000 (AEST)" }, + { "UTC", "+0000 (UTC)" }, + { 0 }, + }; + char obuf[1024] = ""; + char ebuf[1024] = ""; + struct pollfd fds[3]; + int opd[2], epd[2], spd[2]; + time_t changed, now; + const struct tzcase *tzcase = NULL; + struct tm *tm; + size_t olen = 0, elen = 0; + ssize_t rlen; + long curoff = LONG_MIN; + pid_t pid; + int nfds, status; + + /* speed up the test if possible */ + tz_change_interval_p = dlsym(RTLD_SELF, tz_change_interval_sym); + if (tz_change_interval_p != NULL && + *tz_change_interval_p > tz_change_interval) { + debug("reducing detection interval from %d to %d", + *tz_change_interval_p, tz_change_interval); + *tz_change_interval_p = tz_change_interval; + tz_change_timeout = tz_change_interval * 3; + } + /* prepare chroot */ + ATF_REQUIRE_EQ(0, mkdir("root", 0755)); + ATF_REQUIRE_EQ(0, mkdir("root/etc", 0755)); + change_tz("UTC"); + time(&changed); + /* output, error, sync pipes */ + if (pipe(opd) != 0 || pipe(epd) != 0 || pipe(spd) != 0) + atf_tc_fail("failed to pipe"); + /* fork child */ + if ((pid = fork()) < 0) + atf_tc_fail("failed to fork"); + if (pid == 0) { + /* child */ + dup2(opd[1], STDOUT_FILENO); + close(opd[0]); + close(opd[1]); + dup2(epd[1], STDERR_FILENO); + close(epd[0]); + close(epd[1]); + close(spd[0]); + unsetenv("TZ"); + ATF_REQUIRE_EQ(0, chroot("root")); + ATF_REQUIRE_EQ(0, chdir("/")); + fds[0].fd = spd[1]; + fds[0].events = POLLIN; + for (;;) { + ATF_REQUIRE(poll(fds, 1, 100) >= 0); + if (fds[0].revents & POLLHUP) { + /* parent closed sync pipe */ + _exit(0); + } + ATF_REQUIRE((tm = localtime(&then)) != NULL); + if (tm->tm_gmtoff == curoff) + continue; + olen = strftime(obuf, sizeof(obuf), "%z (%Z)", tm); + ATF_REQUIRE(olen > 0); + fprintf(stdout, "%s\n", obuf); + fflush(stdout); + curoff = tm->tm_gmtoff; + } + _exit(2); + } + /* parent */ + close(opd[1]); + close(epd[1]); + close(spd[1]); + /* receive output until child terminates */ + fds[0].fd = opd[0]; + fds[0].events = POLLIN; + fds[1].fd = epd[0]; + fds[1].events = POLLIN; + fds[2].fd = spd[0]; + fds[2].events = POLLIN; + nfds = 3; + for (;;) { + ATF_REQUIRE(poll(fds, 3, 1000) >= 0); + time(&now); + if (fds[0].revents & POLLIN && olen < sizeof(obuf)) { + rlen = read(opd[0], obuf + olen, sizeof(obuf) - olen); + ATF_REQUIRE(rlen >= 0); + olen += rlen; + } + if (olen > 0) { + ATF_REQUIRE_EQ('\n', obuf[olen - 1]); + obuf[--olen] = '\0'; + /* tzcase will be NULL at first */ + if (tzcase != NULL) { + debug("%s", obuf); + ATF_REQUIRE_STREQ(tzcase->expect, obuf); + debug("change to %s detected after %d s", + tzcase->tzfn, (int)(now - changed)); + if (tz_change_interval_p != NULL) { + ATF_CHECK((int)(now - changed) >= + *tz_change_interval_p - 1); + ATF_CHECK((int)(now - changed) <= + *tz_change_interval_p + 1); + } + } + olen = 0; + /* first / next test case */ + if (tzcase == NULL) + tzcase = tzcases; + else + tzcase++; + if (tzcase->tzfn == NULL) { + /* test is over */ + break; + } + change_tz(tzcase->tzfn); + changed = now; + } + if (fds[1].revents & POLLIN && elen < sizeof(ebuf)) { + rlen = read(epd[0], ebuf + elen, sizeof(ebuf) - elen); + ATF_REQUIRE(rlen >= 0); + elen += rlen; + } + if (elen > 0) { + ATF_REQUIRE_EQ(elen, fwrite(ebuf, 1, elen, stderr)); + elen = 0; + } + if (nfds > 2 && fds[2].revents & POLLHUP) { + /* child closed sync pipe */ + break; + } + /* + * The timeout for this test case is set to 10 minutes, + * because it can take that long to run with the default + * 61-second interval. However, each individual tzcase + * entry should not take much longer than the detection + * interval to test, so we can detect a problem long + * before Kyua terminates us. + */ + if ((now - changed) > tz_change_timeout) { + close(spd[0]); + if (tz_change_interval_p == NULL && + tzcase == tzcases) { + /* + * The most likely explanation in this + * case is that libc was built without + * time zone change detection. + */ + atf_tc_skip("time zone change detection " + "does not appear to be enabled"); + } + atf_tc_fail("timed out waiting for change to %s " + "to be detected", tzcase->tzfn); + } + } + close(opd[0]); + close(epd[0]); + close(spd[0]); /* this will wake up and terminate the child */ + if (olen > 0) + ATF_REQUIRE_EQ(olen, fwrite(obuf, 1, olen, stdout)); + if (elen > 0) + ATF_REQUIRE_EQ(elen, fwrite(ebuf, 1, elen, stderr)); + ATF_REQUIRE_EQ(pid, waitpid(pid, &status, 0)); + ATF_REQUIRE(WIFEXITED(status)); + ATF_REQUIRE_EQ(0, WEXITSTATUS(status)); +} + +ATF_TP_ADD_TCS(tp) +{ + debugging = !getenv("__RUNNING_INSIDE_ATF_RUN") && + isatty(STDERR_FILENO); + ATF_TP_ADD_TC(tp, detect_tz_changes); + return (atf_no_error()); +} |