Comment update to correct for microseconds not always rounding up + a…

…dded dubug message
nasa · Apr 7, 2020 · 76bb76b · 76bb76b
1 parent 20a83c4
commit 76bb76b
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Showing 3 changed files with 18 additions and 3 deletions.
diff --git a/src/os/posix/ostimer.c b/src/os/posix/ostimer.c
@@ -285,9 +285,10 @@ int32 OS_Posix_TimeBaseAPI_Impl_Init(void)
  }
 
  /*
- * Calculate microseconds per tick - Rounding UP
- * - If the ratio is not an integer, this will choose the next higher value
- * - The result is guaranteed not to be zero.
+ * Calculate microseconds per tick 
+ * - If the ratio is not an integer, this will round to the nearest integer value
+ * - This is used internally for reporting accuracy,
+ * - TicksPerSecond values over 2M will return zero
  */
  OS_SharedGlobalVars.MicroSecPerTick = (1000000 + (OS_SharedGlobalVars.TicksPerSecond / 2)) /
  OS_SharedGlobalVars.TicksPerSecond;

diff --git a/src/os/shared/osapi-common.c b/src/os/shared/osapi-common.c
@@ -64,6 +64,7 @@ int32 OS_API_Init(void)
 {
  int32 return_code = OS_SUCCESS;
  uint32 idtype;
+ uint32 microSecPerSec;
 
  if (OS_SharedGlobalVars.Initialized != false)
  {
@@ -161,6 +162,14 @@ int32 OS_API_Init(void)
  return_code = OS_ERROR;
  }
 
+ microSecPerSec = OS_SharedGlobalVars.MicroSecPerTick * OS_SharedGlobalVars.TicksPerSecond;
+
+ if ( microSecPerSec != 1000000 )
+ { 
+ OS_DEBUG("Warning: Microsecs per sec value of %lu does not equal 1000000 (MicroSecPerTick: %ld TicksPerSecond: %ld)\n", 
+ (unsigned long) microSecPerSec, (long) OS_SharedGlobalVars.MicroSecPerTick, (long) OS_SharedGlobalVars.TicksPerSecond);
+ }
+
  return(return_code);
 } /* end OS_API_Init */
 

diff --git a/src/unit-test-coverage/shared/src/coveragetest-common.c b/src/unit-test-coverage/shared/src/coveragetest-common.c
@@ -97,6 +97,11 @@ void Test_OS_API_Init(void)
  OS_SharedGlobalVars.Initialized = false;
  OSAPI_TEST_FUNCTION_RC(OS_API_Init(), OS_SUCCESS);
 
+ Test_MicroSecPerTick = 1000;
+ Test_TicksPerSecond = 1001;
+ OS_SharedGlobalVars.Initialized = false;
+ OSAPI_TEST_FUNCTION_RC(OS_API_Init(), OS_SUCCESS);
+
  /* Second call should return ERROR */
  OSAPI_TEST_FUNCTION_RC(OS_API_Init(), OS_ERROR);