From 18631151c81a92341d26cee6f3b125191f3d5c41 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Tue, 31 May 2011 13:44:36 +0930 Subject: [PATCH] time: new module for dealing with time. --- ccan/time/LICENSE | 1 + ccan/time/_info | 47 +++++++++++ ccan/time/test/run.c | 111 ++++++++++++++++++++++++++ ccan/time/time.c | 107 +++++++++++++++++++++++++ ccan/time/time.h | 183 +++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 449 insertions(+) create mode 120000 ccan/time/LICENSE create mode 100644 ccan/time/_info create mode 100644 ccan/time/test/run.c create mode 100644 ccan/time/time.c create mode 100644 ccan/time/time.h diff --git a/ccan/time/LICENSE b/ccan/time/LICENSE new file mode 120000 index 00000000..2354d129 --- /dev/null +++ b/ccan/time/LICENSE @@ -0,0 +1 @@ +../../licenses/BSD-MIT \ No newline at end of file diff --git a/ccan/time/_info b/ccan/time/_info new file mode 100644 index 00000000..fdad2756 --- /dev/null +++ b/ccan/time/_info @@ -0,0 +1,47 @@ +#include +#include "config.h" + +/** + * time - routines for dealing with time + * + * This code provides convenient functions for working with time. + * + * Author: Rusty Russell + * License: BSD-MIT + * + * Example: + * #include + * #include + * #include + * #include + * + * int main(int argc, char *argv[]) + * { + * struct timeval t; + * + * if (argc != 2) + * errx(1, "Usage: %s ", argv[0]); + * + * t = time_now(); + * if (argv[1][0] == '-') + * t = time_sub(t, time_from_msec(atol(argv[1]+1))); + * else + * t = time_add(t, time_from_msec(atol(argv[1]))); + * + * printf("%lu.%06u\n", + * (unsigned long)t.tv_sec, (unsigned)t.tv_usec); + * return 0; + * } + */ +int main(int argc, char *argv[]) +{ + /* Expect exactly one argument */ + if (argc != 2) + return 1; + + if (strcmp(argv[1], "depends") == 0) { + return 0; + } + + return 1; +} diff --git a/ccan/time/test/run.c b/ccan/time/test/run.c new file mode 100644 index 00000000..80391694 --- /dev/null +++ b/ccan/time/test/run.c @@ -0,0 +1,111 @@ +#include +#include +#include + +int main(void) +{ + struct timeval t1, t2, t3, zero = { 0, 0 }; + + plan_tests(46); + + /* Test time_now */ + t1 = time_now(); + t2 = time_now(); + + /* Test time_sub. */ + t3 = time_sub(t2, t1); + ok1(t3.tv_sec > 0 || t3.tv_usec >= 0); + t3 = time_sub(t2, t2); + ok1(t3.tv_sec == 0 && t3.tv_usec == 0); + t3 = time_sub(t1, t1); + ok1(t3.tv_sec == 0 && t3.tv_usec == 0); + + /* Test time_eq */ + ok1(time_eq(t1, t1)); + ok1(time_eq(t2, t2)); + ok1(!time_eq(t1, t3)); + ok1(!time_eq(t2, t3)); + + /* Make sure t2 > t1. */ + t3.tv_sec = 0; + t3.tv_usec = 1; + t2 = time_add(t2, t3); + + /* Test time_less and time_greater. */ + ok1(!time_eq(t1, t2)); + ok1(!time_greater(t1, t2)); + ok1(time_less(t1, t2)); + ok1(time_greater(t2, t1)); + ok1(!time_less(t2, t1)); + t3.tv_sec = 0; + t3.tv_usec = 999999; + t2 = time_add(t2, t3); + ok1(!time_eq(t1, t2)); + ok1(!time_greater(t1, t2)); + ok1(time_less(t1, t2)); + ok1(time_greater(t2, t1)); + ok1(!time_less(t2, t1)); + + t3 = time_sub(t2, zero); + ok1(time_eq(t3, t2)); + t3 = time_sub(t2, t2); + ok1(time_eq(t3, zero)); + + /* time_from_msec / time_to_msec */ + t3 = time_from_msec(500); + ok1(t3.tv_sec == 0); + ok1(t3.tv_usec == 500000); + ok1(time_to_msec(t3) == 500); + + t3 = time_from_msec(1000); + ok1(t3.tv_sec == 1); + ok1(t3.tv_usec == 0); + ok1(time_to_msec(t3) == 1000); + + t3 = time_from_msec(1500); + ok1(t3.tv_sec == 1); + ok1(t3.tv_usec == 500000); + ok1(time_to_msec(t3) == 1500); + + /* time_from_usec */ + t3 = time_from_usec(500000); + ok1(t3.tv_sec == 0); + ok1(t3.tv_usec == 500000); + ok1(time_to_usec(t3) == 500000); + + t3 = time_from_usec(1000000); + ok1(t3.tv_sec == 1); + ok1(t3.tv_usec == 0); + ok1(time_to_usec(t3) == 1000000); + + t3 = time_from_usec(1500000); + ok1(t3.tv_sec == 1); + ok1(t3.tv_usec == 500000); + ok1(time_to_usec(t3) == 1500000); + + /* Test wrapunder */ + t3 = time_sub(time_sub(t2, time_from_msec(500)), time_from_msec(500)); + ok1(t3.tv_sec == t2.tv_sec - 1); + ok1(t3.tv_usec == t2.tv_usec); + + /* time_divide and time_multiply */ + t1.tv_usec = 100; + t1.tv_sec = 100; + + t3 = time_divide(t1, 2); + ok1(t3.tv_sec == 50); + ok1(t3.tv_usec == 50); + + t3 = time_divide(t1, 100); + ok1(t3.tv_sec == 1); + ok1(t3.tv_usec == 1); + + t3 = time_multiply(t3, 100); + ok1(time_eq(t3, t1)); + + t3 = time_divide(t1, 200); + ok1(t3.tv_sec == 0); + ok1(t3.tv_usec == 500000); + + return exit_status(); +} diff --git a/ccan/time/time.c b/ccan/time/time.c new file mode 100644 index 00000000..1f36c081 --- /dev/null +++ b/ccan/time/time.c @@ -0,0 +1,107 @@ +#include +#include +#include + +struct timeval time_now(void) +{ + struct timeval now; + gettimeofday(&now, NULL); + return now; +} + +bool time_greater(struct timeval a, struct timeval b) +{ + if (a.tv_sec > b.tv_sec) + return true; + else if (a.tv_sec < b.tv_sec) + return false; + + return a.tv_usec > b.tv_usec; +} + +bool time_less(struct timeval a, struct timeval b) +{ + if (a.tv_sec < b.tv_sec) + return true; + else if (a.tv_sec > b.tv_sec) + return false; + + return a.tv_usec < b.tv_usec; +} + +bool time_eq(struct timeval a, struct timeval b) +{ + return a.tv_sec == b.tv_sec && a.tv_usec == b.tv_usec; +} + +struct timeval time_sub(struct timeval recent, struct timeval old) +{ + struct timeval diff; + + diff.tv_sec = recent.tv_sec - old.tv_sec; + if (old.tv_usec > recent.tv_usec) { + diff.tv_sec--; + diff.tv_usec = 1000000 + recent.tv_usec - old.tv_usec; + } else + diff.tv_usec = recent.tv_usec - old.tv_usec; + + assert(diff.tv_sec >= 0); + return diff; +} + +struct timeval time_add(struct timeval a, struct timeval b) +{ + struct timeval sum; + + sum.tv_sec = a.tv_sec + b.tv_sec; + sum.tv_usec = a.tv_usec + b.tv_usec; + if (sum.tv_usec > 1000000) { + sum.tv_sec++; + sum.tv_usec -= 1000000; + } + return sum; +} + +struct timeval time_divide(struct timeval t, unsigned long div) +{ + return time_from_usec(time_to_usec(t) / div); +} + +struct timeval time_multiply(struct timeval t, unsigned long mult) +{ + return time_from_usec(time_to_usec(t) * mult); +} + +uint64_t time_to_msec(struct timeval t) +{ + uint64_t msec; + + msec = t.tv_usec / 1000 + (uint64_t)t.tv_sec * 1000; + return msec; +} + +uint64_t time_to_usec(struct timeval t) +{ + uint64_t usec; + + usec = t.tv_usec + (uint64_t)t.tv_sec * 1000000; + return usec; +} + +struct timeval time_from_msec(uint64_t msec) +{ + struct timeval t; + + t.tv_usec = (msec % 1000) * 1000; + t.tv_sec = msec / 1000; + return t; +} + +struct timeval time_from_usec(uint64_t usec) +{ + struct timeval t; + + t.tv_usec = usec % 1000000; + t.tv_sec = usec / 1000000; + return t; +} diff --git a/ccan/time/time.h b/ccan/time/time.h new file mode 100644 index 00000000..e3a57911 --- /dev/null +++ b/ccan/time/time.h @@ -0,0 +1,183 @@ +#ifndef CCAN_TIME_H +#define CCAN_TIME_H +#include "config.h" +#include +#include +#include + +/** + * time_now - return the current time + * + * Example: + * printf("Now is %lu seconds since epoch\n", (long)time_now().tv_sec); + */ +struct timeval time_now(void); + +/** + * time_greater - is a after b? + * @a: one time. + * @b: another time. + * + * Example: + * static bool timed_out(const struct timeval *start) + * { + * #define TIMEOUT time_from_msec(1000) + * return time_greater(time_now(), time_add(*start, TIMEOUT)); + * } + */ +bool time_greater(struct timeval a, struct timeval b); + +/** + * time_less - is a before b? + * @a: one time. + * @b: another time. + * + * Example: + * static bool still_valid(const struct timeval *start) + * { + * #define TIMEOUT time_from_msec(1000) + * return time_less(time_now(), time_add(*start, TIMEOUT)); + * } + */ +bool time_less(struct timeval a, struct timeval b); + +/** + * time_eq - is a equal to b? + * @a: one time. + * @b: another time. + * + * Example: + * #include + * #include + * + * // Can we fork in under a microsecond? + * static bool fast_fork(void) + * { + * struct timeval start = time_now(); + * if (fork() != 0) { + * exit(0); + * } + * wait(NULL); + * return time_eq(start, time_now()); + * } + */ +bool time_eq(struct timeval a, struct timeval b); + +/** + * time_sub - subtract two times + * @recent: the larger (more recent) time. + * @old: the smaller (less recent) time. + * + * This returns a well formed struct timeval. + * + * Example: + * static bool was_recent(const struct timeval *start) + * { + * return time_sub(time_now(), *start).tv_sec < 1; + * } + */ +struct timeval time_sub(struct timeval recent, struct timeval old); + +/** + * time_add - add two times + * @a: one time. + * @b: another time. + * + * The times must not overflow, or the results are undefined. + * + * Example: + * // We do one every second. + * static struct timeval next_time(void) + * { + * return time_add(time_now(), time_from_msec(1000)); + * } + */ +struct timeval time_add(struct timeval a, struct timeval b); + +/** + * time_divide - divide a time by a value. + * @t: a time. + * @div: number to divide it by. + * + * Example: + * // How long does it take to do a fork? + * static struct timeval forking_time(void) + * { + * struct timeval start = time_now(); + * unsigned int i; + * + * for (i = 0; i < 1000; i++) { + * if (fork() != 0) { + * exit(0); + * } + * wait(NULL); + * } + * return time_divide(time_sub(time_now(), start), i); + * } + */ +struct timeval time_divide(struct timeval t, unsigned long div); + +/** + * time_multiply - multiply a time by a value. + * @t: a time. + * @mult: number to multiply it by. + * + * Example: + * ... + * printf("Time to do 100000 forks would be %u sec\n", + * (unsigned)time_multiply(forking_time(), 1000000).tv_sec); + */ +struct timeval time_multiply(struct timeval t, unsigned long mult); + +/** + * time_to_msec - return number of milliseconds + * @t: a time + * + * It's often more convenient to deal with time values as + * milliseconds. Note that this will fit into a 32-bit variable if + * it's a time difference of less than ~7 weeks. + * + * Example: + * ... + * printf("Forking time is %u msec\n", + * (unsigned)time_to_msec(forking_time())); + */ +uint64_t time_to_msec(struct timeval t); + +/** + * time_to_usec - return number of microseconds + * @t: a time + * + * It's often more convenient to deal with time values as + * microseconds. Note that this will fit into a 32-bit variable if + * it's a time difference of less than ~1 hour. + * + * Example: + * ... + * printf("Forking time is %u usec\n", + * (unsigned)time_to_usec(forking_time())); + * + */ +uint64_t time_to_usec(struct timeval t); + +/** + * time_from_msec - convert milliseconds to a timeval + * @msec: time in milliseconds + * + * Example: + * // 1/2 second timeout + * #define TIMEOUT time_from_msec(500) + */ +struct timeval time_from_msec(uint64_t msec); + +/** + * time_from_usec - convert microseconds to a timeval + * @usec: time in microseconds + * + * Example: + * // 1/2 second timeout + * #define TIMEOUT time_from_usec(500000) + */ +struct timeval time_from_usec(uint64_t usec); + +#endif /* CCAN_TIME_H */ -- 2.39.2