tests/utils/utils.c

   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 }