[LinuxPPS] [PATCH] time_pps_readlink()

[Rodolfo Giometti]

Hello,

here a patch to implement a new userland function to simplify userland
code.

By using the time_pps_readlink() function you can move from this code:

   +#ifdef PPS_HAVE_FINDPATH
   +      /* Get the PPS source's real name */
   +      fd = readlink(link, path, STRING_LEN-1);
   +      if (fd <= 0)
   +              strncpy(path, link, STRING_LEN);
   +      else
   +              path[fd] = '\0';
   +
   +      /* Try to find the source */
   +      fd = time_pps_findpath(path, STRING_LEN, id, STRING_LEN);
   +      if (fd < 0) {
   +              msyslog(LOG_ERR, "refclock: cannot find PPS source \"%s\" in the system",
   PPS_DEVICE);
   +              return 1;
   +      }
   +      msyslog(LOG_INFO, "refclock: found PPS source \"%s\" at id #%d on \"%s\"", PPS_DEV
   ICE, fd, id);
   +#endif   /* PPS_HAVE_FINDPATH */

to this code:

   +#ifdef PPS_HAVE_FINDPATH
   +      /* Get the PPS source's real name */
   +      time_pps_readlink(link, STRING_LEN, path, STRING_LEN);
   +
   +      /* Try to find the source */
   +      fd = time_pps_findpath(path, STRING_LEN, id, STRING_LEN);
   +      if (fd < 0) {
   +              msyslog(LOG_ERR, "refclock: cannot find PPS source \"%s\" in the system",
   PPS_DEVICE);
   +              return 1;
   +      }
   +      msyslog(LOG_INFO, "refclock: found PPS source \"%s\" at id #%d on \"%s\"", PPS_DEV
   ICE, fd, id);
   +#endif   /* PPS_HAVE_FINDPATH */

You can use the attached patch or just upgrading your GIT repository
from my server and using branch "dev_time_pps_readlink".

Please, let me know what do you think about it.

Ciao,

Rodolfo

-- 

GNU/Linux Solutions                  e-mail:    giometti at enneenne.com
Linux Device Driver                             giometti at gnudd.com
Embedded Systems                     		giometti at linux.it
UNIX programming                     phone:     +39 349 2432127
-------------- next part --------------
diff --git a/include/linux/timepps.h b/include/linux/timepps.h
index 499f849..93fe2bb 100644
--- a/include/linux/timepps.h
+++ b/include/linux/timepps.h
@@ -183,6 +183,7 @@ #else /* !__KERNEL__ */
 
 /* --- 3.4 Functions ------------------------------------------------------- */
 
+#include <unistd.h>
 #include <errno.h>
 #include <asm/types.h>
 #include <sys/socket.h>
@@ -453,6 +454,22 @@ static __inline int time_pps_findsource(
 }
 
 #define PPS_HAVE_FINDPATH	1
+static __inline void time_pps_readlink(char *link, int linklen, char *path, int pathlen)
+{
+	int i;
+
+	i = readlink(link, path, pathlen-1);
+	if (i <= 0) {
+		/* "link" is not a valid symbolic so we directly use it */
+		strncpy(path, link, linklen <= pathlen ? linklen : pathlen);
+		return;
+	}
+
+	/* Return the file name where "link" points to */
+	path[i] = '\0';
+	return;
+}
+
 static __inline int time_pps_findpath(char *path, int pathlen, char *idstring, int idlen)
 {
 	int sock;