improved max connections code. Now use fcntl instead of flock.

[rsync.git] / util.c

diff --git a/util.c b/util.c
index f74228ef83ca1dfee21de3955d7f0515df60e0db..7d15a8a605c973fbfe0fd264a19421299adcb816 100644 (file)
--- a/util.c
+++ b/util.c
@@ -446,3 +446,61 @@ void kill_all(int sig)
        }
 }
 
+/* like strncpy but does not 0 fill the buffer and always null 
+   terminates (thus it can use maxlen+1 space in d) */
+void strlcpy(char *d, char *s, int maxlen)
+{
+       int len = strlen(s);
+       if (len > maxlen) len = maxlen;
+       memcpy(d, s, len);
+       d[len] = 0;
+}
+
+/* turn a user name into a uid */
+int name_to_uid(char *name, uid_t *uid)
+{
+       struct passwd *pass;
+       if (!name || !*name) return 0;
+       pass = getpwnam(name);
+       if (pass) {
+               *uid = pass->pw_uid;
+               return 1;
+       }
+       return 0;
+}
+
+/* turn a group name into a gid */
+int name_to_gid(char *name, gid_t *gid)
+{
+       struct group *grp;
+       if (!name || !*name) return 0;
+       grp = getgrnam(name);
+       if (grp) {
+               *gid = grp->gr_gid;
+               return 1;
+       }
+       return 0;
+}
+
+
+/****************************************************************************
+check if a process exists. 
+****************************************************************************/
+int process_exists(int pid)
+{
+       return(kill(pid,0) == 0 || errno != ESRCH);
+}
+
+/* lock a byte range in a open file */
+int lock_range(int fd, int offset, int len)
+{
+       struct flock lock;
+
+       lock.l_type = F_WRLCK;
+       lock.l_whence = SEEK_SET;
+       lock.l_start = offset;
+       lock.l_len = len;
+       lock.l_pid = 0;
+       
+       return fcntl(fd,F_SETLK,&lock) == 0;
+}