phc2sys, phc_ctl: Re-factor common code.

The two programs, phc2sys and phc_ctl, use nearly identical subroutines to
open an instance of a dynamic posix clock.  In anticipation of yet a third
program with similar needs, this patch refactors the common code into the
utilities.

Signed-off-by: Richard Cochran <richardcochran@gmail.com>

makefile

@@ -55,10 +55,10 @@ all: $(PRG)
 
 ptp4l: $(OBJ)
 
-nsm: config.o filter.o hash.o mave.o mmedian.o msg.o nsm.o print.o raw.o \
+nsm: config.o filter.o hash.o mave.o mmedian.o msg.o nsm.o phc.o print.o raw.o \
  rtnl.o sk.o transport.o tlv.o tsproc.o udp.o udp6.o uds.o util.o version.o
 
-pmc: config.o hash.o msg.o pmc.o pmc_common.o print.o raw.o sk.o tlv.o \
+pmc: config.o hash.o msg.o phc.o pmc.o pmc_common.o print.o raw.o sk.o tlv.o \
  transport.o udp.o udp6.o uds.o util.o version.o
 
 phc2sys: clockadj.o clockcheck.o config.o hash.o linreg.o msg.o ntpshm.o \
@@ -69,14 +69,14 @@ hwstamp_ctl: hwstamp_ctl.o version.o
 
 phc_ctl: phc_ctl.o phc.o sk.o util.o clockadj.o sysoff.o print.o version.o
 
-snmp4lptp: config.o hash.o msg.o pmc_common.o print.o raw.o sk.o \
+snmp4lptp: config.o hash.o msg.o phc.o pmc_common.o print.o raw.o sk.o \
  snmp4lptp.o tlv.o transport.o udp.o udp6.o uds.o util.o
 	$(CC) $^ $(LDFLAGS) $(LOADLIBES) $(LDLIBS) $(snmplib) -o $@
 
 snmp4lptp.o: snmp4lptp.c
 	$(CC) $(CPPFLAGS) $(CFLAGS) $(snmpflg) -c $<
 
-timemaster: print.o rtnl.o sk.o timemaster.o util.o version.o
+timemaster: phc.o print.o rtnl.o sk.o timemaster.o util.o version.o
 
 version.o: .version version.sh $(filter-out version.d,$(DEPEND))
 

phc2sys.c

@@ -135,40 +135,6 @@ static int run_pmc_port_properties(struct node *node, int timeout,
 				   unsigned int port,
 				   int *state, int *tstamping, char *iface);
 
-static clockid_t clock_open(char *device, int *phc_index)
-{
-	struct sk_ts_info ts_info;
-	char phc_device[19];
-	int clkid;
-
-	/* check if device is CLOCK_REALTIME */
-	if (!strcasecmp(device, "CLOCK_REALTIME"))
-		return CLOCK_REALTIME;
-
-	/* check if device is valid phc device */
-	clkid = phc_open(device);
-	if (clkid != CLOCK_INVALID)
-		return clkid;
-
-	/* check if device is a valid ethernet device */
-	if (sk_get_ts_info(device, &ts_info) || !ts_info.valid) {
-		fprintf(stderr, "unknown clock %s: %m\n", device);
-		return CLOCK_INVALID;
-	}
-
-	if (ts_info.phc_index < 0) {
-		fprintf(stderr, "interface %s does not have a PHC\n", device);
-		return CLOCK_INVALID;
-	}
-
-	sprintf(phc_device, "/dev/ptp%d", ts_info.phc_index);
-	clkid = phc_open(phc_device);
-	if (clkid == CLOCK_INVALID)
-		fprintf(stderr, "cannot open %s: %m\n", device);
-	*phc_index = ts_info.phc_index;
-	return clkid;
-}
-
 static struct servo *servo_add(struct node *node, struct clock *clock)
 {
 	double ppb;
@@ -210,7 +176,7 @@ static struct clock *clock_add(struct node *node, char *device)
 	int phc_index = -1;
 
 	if (device) {
-		clkid = clock_open(device, &phc_index);
+		clkid = posix_clock_open(device, &phc_index);
 		if (clkid == CLOCK_INVALID)
 			return NULL;
 	}
@@ -371,7 +337,7 @@ static void clock_reinit(struct node *node, struct clock *clock, int new_state)
 		/* Check if phc index changed */
 		if (!sk_get_ts_info(clock->device, &ts_info) &&
 		    clock->phc_index != ts_info.phc_index) {
-			clkid = clock_open(clock->device, &phc_index);
+			clkid = posix_clock_open(clock->device, &phc_index);
 			if (clkid == CLOCK_INVALID)
 				return;
 

phc_ctl.c

@@ -110,39 +110,6 @@ static int64_t calculate_offset(struct timespec *ts1,
 	return offset;
 }
 
-static clockid_t clock_open(char *device)
-{
-	struct sk_ts_info ts_info;
-	char phc_device[19];
-	int clkid;
-
-	/* check if device is CLOCK_REALTIME */
-	if (!strcasecmp(device, "CLOCK_REALTIME"))
-		return CLOCK_REALTIME;
-
-	/* check if device is valid phc device */
-	clkid = phc_open(device);
-	if (clkid != CLOCK_INVALID)
-		return clkid;
-
-	/* check if device is a valid ethernet device */
-	if (sk_get_ts_info(device, &ts_info) || !ts_info.valid) {
-		pr_err("unknown clock %s: %m", device);
-		return CLOCK_INVALID;
-	}
-
-	if (ts_info.phc_index < 0) {
-		pr_err("interface %s does not have a PHC", device);
-		return CLOCK_INVALID;
-	}
-
-	sprintf(phc_device, "/dev/ptp%d", ts_info.phc_index);
-	clkid = phc_open(phc_device);
-	if (clkid == CLOCK_INVALID)
-		pr_err("cannot open %s for %s: %m", phc_device, device);
-	return clkid;
-}
-
 static void usage(const char *progname)
 {
 	fprintf(stderr,
@@ -503,10 +470,10 @@ static int run_cmds(clockid_t clkid, int cmdc, char *cmdv[])
 
 int main(int argc, char *argv[])
 {
-	const char *progname;
+	int c, cmdc, junk, print_level = LOG_INFO, result;
 	char **cmdv, *default_cmdv[] = { "caps" };
-	int c, result, cmdc;
+	int use_syslog = 1, verbose = 1;
-	int print_level = LOG_INFO, verbose = 1, use_syslog = 1;
+	const char *progname;
 	clockid_t clkid;
 
 	install_handler(SIGALRM, handle_alarm);
@@ -558,7 +525,7 @@ int main(int argc, char *argv[])
 		cmdc = argc - optind - 1;
 	}
 
-	clkid = clock_open(argv[optind]);
+	clkid = posix_clock_open(argv[optind], &junk);
 	if (clkid == CLOCK_INVALID)
 		return -1;
 

util.c

@@ -25,6 +25,7 @@
 #include <string.h>
 
 #include "address.h"
+#include "phc.h"
 #include "print.h"
 #include "sk.h"
 #include "util.h"
@@ -171,6 +172,39 @@ char *portaddr2str(struct PortAddress *addr)
 	return buf;
 }
 
+clockid_t posix_clock_open(char *device, int *phc_index)
+{
+	struct sk_ts_info ts_info;
+	char phc_device[19];
+	int clkid;
+
+	/* check if device is CLOCK_REALTIME */
+	if (!strcasecmp(device, "CLOCK_REALTIME")) {
+		return CLOCK_REALTIME;
+	}
+	/* check if device is valid phc device */
+	clkid = phc_open(device);
+	if (clkid != CLOCK_INVALID) {
+		return clkid;
+	}
+	/* check if device is a valid ethernet device */
+	if (sk_get_ts_info(device, &ts_info) || !ts_info.valid) {
+		pr_err("unknown clock %s: %m", device);
+		return CLOCK_INVALID;
+	}
+	if (ts_info.phc_index < 0) {
+		pr_err("interface %s does not have a PHC", device);
+		return CLOCK_INVALID;
+	}
+	snprintf(phc_device, sizeof(phc_device), "/dev/ptp%d", ts_info.phc_index);
+	clkid = phc_open(phc_device);
+	if (clkid == CLOCK_INVALID) {
+		pr_err("cannot open %s for %s: %m", phc_device, device);
+	}
+	*phc_index = ts_info.phc_index;
+	return clkid;
+}
+
 int str2addr(enum transport_type type, const char *s, struct address *addr)
 {
 	unsigned char mac[MAC_LEN];

util.h

@@ -103,6 +103,14 @@ char *pid2str(struct PortIdentity *id);
 
 char *portaddr2str(struct PortAddress *addr);
 
+/**
+ * Opens a dynamic posix clock by name.
+ * @param device     The PHC character device or network interface to open.
+ * @param phc_index  Returns the PHC index, if any.
+ * @return           A valid clock ID on success or CLOCK_INVALID otherwise.
+ */
+clockid_t posix_clock_open(char *device, int *phc_index);
+
 /**
  * Compare two port identities for equality.
  *