Merging upstream version 2.40.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 89 insertions, 31 deletions

diff --git a/libuuid/src/gen_uuid.c b/libuuid/src/gen_uuid.c
index 826cd22..59e8c23 100644
--- a/libuuid/src/gen_uuid.c
+++ b/libuuid/src/gen_uuid.c
@@ -207,6 +207,28 @@ static int get_node_id(unsigned char *node_id)
 	return 0;
 }
 
+enum { STATE_FD_ERROR = -1, STATE_FD_INIT = -2 };
+
+static int state_fd_init(const char *clock_file, FILE **fp)
+{
+	mode_t save_umask;
+	int state_fd;
+	FILE *state_f;
+
+	save_umask = umask(0);
+	state_fd = open(clock_file, O_RDWR|O_CREAT|O_CLOEXEC, 0660);
+	(void) umask(save_umask);
+	if (state_fd != -1) {
+		state_f = fdopen(state_fd, "r+" UL_CLOEXECSTR);
+		if (!state_f) {
+			close(state_fd);
+			state_fd = STATE_FD_ERROR;
+		} else
+			*fp = state_f;
+	}
+	return state_fd;
+}
+
 /* Assume that the gettimeofday() has microsecond granularity */
 #define MAX_ADJUSTMENT 10
 /* Reserve a clock_seq value for the 'continuous clock' implementation */
@@ -223,32 +245,16 @@ static int get_clock(uint32_t *clock_high, uint32_t *clock_low,
 {
 	THREAD_LOCAL int		adjustment = 0;
 	THREAD_LOCAL struct timeval	last = {0, 0};
-	THREAD_LOCAL int		state_fd = -2;
+	THREAD_LOCAL int		state_fd = STATE_FD_INIT;
 	THREAD_LOCAL FILE		*state_f;
 	THREAD_LOCAL uint16_t		clock_seq;
 	struct timeval			tv;
 	uint64_t			clock_reg;
-	mode_t				save_umask;
 	int				ret = 0;
 
-	if (state_fd == -1)
-		ret = -1;
+	if (state_fd == STATE_FD_INIT)
+		state_fd = state_fd_init(LIBUUID_CLOCK_FILE, &state_f);
 
-	if (state_fd == -2) {
-		save_umask = umask(0);
-		state_fd = open(LIBUUID_CLOCK_FILE, O_RDWR|O_CREAT|O_CLOEXEC, 0660);
-		(void) umask(save_umask);
-		if (state_fd != -1) {
-			state_f = fdopen(state_fd, "r+" UL_CLOEXECSTR);
-			if (!state_f) {
-				close(state_fd);
-				state_fd = -1;
-				ret = -1;
-			}
-		}
-		else
-			ret = -1;
-	}
 	if (state_fd >= 0) {
 		rewind(state_f);
 		while (flock(state_fd, LOCK_EX) < 0) {
@@ -256,11 +262,13 @@ static int get_clock(uint32_t *clock_high, uint32_t *clock_low,
 				continue;
 			fclose(state_f);
 			close(state_fd);
-			state_fd = -1;
+			state_fd = STATE_FD_ERROR;
 			ret = -1;
 			break;
 		}
-	}
+	} else
+		ret = -1;
+
 	if (state_fd >= 0) {
 		unsigned int cl;
 		unsigned long tv1, tv2;
@@ -355,44 +363,94 @@ static uint64_t get_clock_counter(void)
 /*
  * Get continuous clock value.
  *
- * Return -1 if there is no further clock counter available,
+ * Return -1 if there is no valid clock counter available,
  * otherwise return 0.
  *
  * This implementation doesn't deliver clock counters based on
  * the current time because last_clock_reg is only incremented
  * by the number of requested UUIDs.
  * max_clock_offset is used to limit the offset of last_clock_reg.
+ * used/reserved UUIDs are written to LIBUUID_CLOCK_CONT_FILE.
  */
 static int get_clock_cont(uint32_t *clock_high,
 			  uint32_t *clock_low,
 			  int num,
 			  uint32_t max_clock_offset)
 {
-	/* 100ns based time offset according to RFC 4122. 4.1.4. */
+	/* all 64bit clock_reg values in this function represent '100ns ticks'
+	 * due to the combination of tv_usec + MAX_ADJUSTMENT */
+
+	/* time offset according to RFC 4122. 4.1.4. */
 	const uint64_t reg_offset = (((uint64_t) 0x01B21DD2) << 32) + 0x13814000;
 	static uint64_t last_clock_reg = 0;
-	uint64_t clock_reg;
+	static uint64_t saved_clock_reg = 0;
+	static int state_fd = STATE_FD_INIT;
+	static FILE *state_f = NULL;
+	uint64_t clock_reg, next_clock_reg;
 
-	if (last_clock_reg == 0)
-		last_clock_reg = get_clock_counter();
+	if (state_fd == STATE_FD_ERROR)
+		return -1;
 
 	clock_reg = get_clock_counter();
+
+	if (state_fd == STATE_FD_INIT) {
+		struct stat st;
+
+		state_fd = state_fd_init(LIBUUID_CLOCK_CONT_FILE, &state_f);
+		if (state_fd == STATE_FD_ERROR)
+			return -1;
+
+		if (fstat(state_fd, &st))
+			goto error;
+
+		if (st.st_size) {
+			rewind(state_f);
+			if (fscanf(state_f, "cont: %"SCNu64"\n", &last_clock_reg) != 1)
+				goto error;
+		} else
+			last_clock_reg = clock_reg;
+
+		saved_clock_reg = last_clock_reg;
+	}
+
 	if (max_clock_offset) {
-		uint64_t clock_offset = max_clock_offset * 10000000ULL;
-		if (last_clock_reg < (clock_reg - clock_offset))
-			last_clock_reg = clock_reg - clock_offset;
+		uint64_t co = 10000000ULL * (uint64_t)max_clock_offset;	// clock_offset in [100ns]
+
+		if ((last_clock_reg + co) < clock_reg)
+			last_clock_reg = clock_reg - co;
 	}
 
 	clock_reg += MAX_ADJUSTMENT;
 
-	if ((last_clock_reg + num) >= clock_reg)
+	next_clock_reg = last_clock_reg + (uint64_t)num;
+	if (next_clock_reg >= clock_reg)
 		return -1;
 
+	if (next_clock_reg >= saved_clock_reg) {
+		uint64_t cl = next_clock_reg + 100000000ULL;	// 10s interval in [100ns]
+		int l;
+
+		rewind(state_f);
+		l = fprintf(state_f, "cont: %020"PRIu64"                   \n", cl);
+		if (l < 30 || fflush(state_f))
+			goto error;
+		saved_clock_reg = cl;
+	}
+
 	*clock_high = (last_clock_reg + reg_offset) >> 32;
 	*clock_low = last_clock_reg + reg_offset;
-	last_clock_reg += num;
+	last_clock_reg = next_clock_reg;
 
 	return 0;
+
+error:
+	if (state_fd >= 0)
+		close(state_fd);
+	if (state_f)
+		fclose(state_f);
+	state_fd = STATE_FD_ERROR;
+	state_f = NULL;
+	return -1;
 }
 
 #if defined(HAVE_UUIDD) && defined(HAVE_SYS_UN_H)