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[PATCH mh/lockfile-retry] lockfile: replace random() by rand()

From
Johannes Sixt <j6t@kdbg.org>
Date
May 30, 2015, 06:23 UTC
Message-ID
<55695770.2040303@kdbg.org>

On Windows, we do not have functions srandom() and random(). Use srand() and rand(). These functions produce random numbers of lesser quality, but for the purpose (a retry time-out) they are still good enough.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
---
There you have it: Look the other way for a while, and people start
using exotic stuff... ;)

This is a build breakage of master on Windows. There are also a few new test suite failures. On of them is in t1404#2, indicating that a DF conflict takes a different error path. I haven't debugged, yet. The lock file retry test fails, too. I'll report back as time permits.

 lockfile.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/lockfile.c b/lockfile.c
index 5a93bc7..ee5cb01 100644
--- a/lockfile.c
+++ b/lockfile.c
@@ -191,7 +191,7 @@ static int lock_file_timeout(struct lock_file *lk, const char *path,
 		return lock_file(lk, path, flags);
 
 	if (!random_initialized) {
-		srandom((unsigned int)getpid());
+		srand((unsigned int)getpid());
 		random_initialized = 1;
 	}
 
@@ -218,7 +218,7 @@ static int lock_file_timeout(struct lock_file *lk, const char *path,
 
 		backoff_ms = multiplier * INITIAL_BACKOFF_MS;
 		/* back off for between 0.75*backoff_ms and 1.25*backoff_ms */
-		wait_us = (750 + random() % 500) * backoff_ms;
+		wait_us = (750 + rand() % 500) * backoff_ms;
 		sleep_microseconds(wait_us);
 		remaining_us -= wait_us;
 
-- 
2.3.2.245.gb5bf9d3
Next: Junio C Hamano
Message 1 of 12 in “lockfile: replace random() by rand()”
  1. lockfile: replace random() by rand()Johannes Sixt, May 30, 2015
  2. Junio C HamanoMay 30, 2015
  3. Johannes SixtJun 4, 2015
  4. Michael HaggertyJun 4, 2015
  5. Junio C HamanoJun 4, 2015
  6. 0/4 Fix file locking with retry and timeout on WindowsJohannes Sixt, Jun 5, 2015
  7. Junio C HamanoJun 5, 2015
  8. Michael HaggertyJun 5, 2015
  9. 1/4 lockfile: replace random() by rand()Johannes Sixt, Jun 5, 2015
  10. 2/4 help.c: wrap wait-only poll() invocation in sleep_millisec()Johannes Sixt, Jun 5, 2015
  11. 3/4 lockfile: convert retry timeout computations to millisecondJohannes Sixt, Jun 5, 2015
  12. 4/4 lockfile: wait using sleep_millisec() instead of select()Johannes Sixt, Jun 5, 2015

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