| 1 | /* |
| 2 | * Copyright (C) 2015 Jérémie Galarneau <jeremie.galarneau@efficios.com> |
| 3 | * |
| 4 | * SPDX-License-Identifier: LGPL-2.1-only |
| 5 | * |
| 6 | */ |
| 7 | |
| 8 | #include <assert.h> |
| 9 | #include <common/compat/time.h> |
| 10 | #include <common/time.h> |
| 11 | #include <errno.h> |
| 12 | #include <fcntl.h> |
| 13 | #include <poll.h> |
| 14 | #include <stdbool.h> |
| 15 | #include <stdint.h> |
| 16 | #include <stdio.h> |
| 17 | #include <stdlib.h> |
| 18 | #include <sys/stat.h> |
| 19 | #include <sys/types.h> |
| 20 | #include <unistd.h> |
| 21 | |
| 22 | #include "utils.h" |
| 23 | |
| 24 | static inline |
| 25 | int64_t elapsed_time_ns(struct timespec *t1, struct timespec *t2) |
| 26 | { |
| 27 | struct timespec delta; |
| 28 | |
| 29 | assert(t1 && t2); |
| 30 | delta.tv_sec = t2->tv_sec - t1->tv_sec; |
| 31 | delta.tv_nsec = t2->tv_nsec - t1->tv_nsec; |
| 32 | return ((int64_t) NSEC_PER_SEC * (int64_t) delta.tv_sec) + |
| 33 | (int64_t) delta.tv_nsec; |
| 34 | } |
| 35 | |
| 36 | int usleep_safe(useconds_t usec) |
| 37 | { |
| 38 | int ret = 0; |
| 39 | struct timespec t1, t2; |
| 40 | int64_t time_remaining_ns = (int64_t) usec * (int64_t) NSEC_PER_USEC; |
| 41 | |
| 42 | ret = lttng_clock_gettime(CLOCK_MONOTONIC, &t1); |
| 43 | if (ret) { |
| 44 | ret = -1; |
| 45 | perror("clock_gettime"); |
| 46 | goto end; |
| 47 | } |
| 48 | |
| 49 | while (time_remaining_ns > 0) { |
| 50 | ret = usleep(time_remaining_ns / (int64_t) NSEC_PER_USEC); |
| 51 | if (ret && errno != EINTR) { |
| 52 | perror("usleep"); |
| 53 | goto end; |
| 54 | } |
| 55 | |
| 56 | ret = lttng_clock_gettime(CLOCK_MONOTONIC, &t2); |
| 57 | if (ret) { |
| 58 | perror("clock_gettime"); |
| 59 | goto end; |
| 60 | } |
| 61 | |
| 62 | time_remaining_ns -= elapsed_time_ns(&t1, &t2); |
| 63 | } |
| 64 | end: |
| 65 | return ret; |
| 66 | } |
| 67 | |
| 68 | int create_file(const char *path) |
| 69 | { |
| 70 | int ret; |
| 71 | |
| 72 | if (!path) { |
| 73 | return -1; |
| 74 | } |
| 75 | |
| 76 | ret = creat(path, S_IRWXU); |
| 77 | if (ret < 0) { |
| 78 | perror("creat"); |
| 79 | return -1; |
| 80 | } |
| 81 | |
| 82 | ret = close(ret); |
| 83 | if (ret < 0) { |
| 84 | perror("close"); |
| 85 | return -1; |
| 86 | } |
| 87 | |
| 88 | return 0; |
| 89 | } |
| 90 | |
| 91 | int wait_on_file(const char *path) |
| 92 | { |
| 93 | int ret; |
| 94 | struct stat buf; |
| 95 | |
| 96 | if (!path) { |
| 97 | return -1; |
| 98 | } |
| 99 | |
| 100 | for (;;) { |
| 101 | ret = stat(path, &buf); |
| 102 | if (ret == -1 && errno == ENOENT) { |
| 103 | ret = poll(NULL, 0, 10); /* 10 ms delay */ |
| 104 | /* Should return 0 everytime */ |
| 105 | if (ret) { |
| 106 | if (ret < 0) { |
| 107 | perror("perror"); |
| 108 | } else { |
| 109 | fprintf(stderr, |
| 110 | "poll return value is larger than zero\n"); |
| 111 | } |
| 112 | return -1; |
| 113 | } |
| 114 | continue; /* retry */ |
| 115 | } |
| 116 | if (ret) { |
| 117 | perror("stat"); |
| 118 | return -1; |
| 119 | } |
| 120 | break; /* found */ |
| 121 | } |
| 122 | |
| 123 | return 0; |
| 124 | } |