X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/0c515f17c44344813e8949fbb684b357ad70cfdf..14ebc5b618ec6d4668e120acc7a75ae8efd677e7:/connection.c

diff --git a/connection.c b/connection.c
index fc7c6667..62818610 100644
--- a/connection.c
+++ b/connection.c
@@ -1,123 +1,46 @@
-/* 
-   Copyright (C) Andrew Tridgell 1998
-   
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
-   (at your option) any later version.
-   
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-   
-   You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-*/
+/*
+ * Support the max connections option.
+ *
+ * Copyright (C) 1998 Andrew Tridgell
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, visit the http://fsf.org website.
+ */
 
-/* support the max connections option */
 #include "rsync.h"
 
-int yield_connection(char *fname, int max_connections)
+/* A simple routine to do connection counting.  This returns 1 on success
+ * and 0 on failure, with errno also being set if the open() failed (errno
+ * will be 0 if the lock request failed). */
+int claim_connection(char *fname, int max_connections)
 {
 	int fd, i;
-	pid_t mypid=getpid(), pid=0;
 
-	if (max_connections <= 0)
+	if (max_connections == 0)
 		return 1;
 
-	fd = open(fname,O_RDWR);
-	if (fd == -1) {
-		rprintf(FERROR,"Couldn't open lock file %s (%s)\n",fname,strerror(errno));
+	if ((fd = open(fname, O_RDWR|O_CREAT, 0600)) < 0)
 		return 0;
-	}
-
-	if (!lock_file(fd)) {
-		rprintf(FERROR,"failed to lock %s\n", fname);
-		close(fd);
-		return 0;
-	}
-
-	/* find the right spot */
-	for (i=0;i<max_connections;i++) {
-		if (read(fd, &pid, sizeof(pid)) != sizeof(pid)) {
-			unlock_file(fd);
-			close(fd);
-			return 0;
-		}
-		if (pid == mypid) break;
-	}
-
-	if (i == max_connections) {
-		rprintf(FERROR,"Entry not found in lock file %s\n",fname);
-		unlock_file(fd);
-		close(fd);
-		return 0;
-	}
 
-	pid = 0;
-  
-	/* remove our mark */
-	if (lseek(fd,i*sizeof(pid),SEEK_SET) != i*sizeof(pid) ||
-	    write(fd, &pid,sizeof(pid)) != sizeof(pid)) {
-		rprintf(FERROR,"Couldn't update lock file %s (%s)\n",fname,strerror(errno));
-		unlock_file(fd);
-		close(fd);
-		return 0;
+	/* Find a free spot. */
+	for (i = 0; i < max_connections; i++) {
+		if (lock_range(fd, i*4, 4))
+			return 1;
 	}
 
-	unlock_file(fd);
 	close(fd);
-	return 1;
-}
-
-
-/****************************************************************************
-simple routine to do connection counting
-****************************************************************************/
-int claim_connection(char *fname,int max_connections)
-{
-	int fd, i;
-	pid_t pid;
-
-	if (max_connections <= 0)
-		return 1;
-	
-	fd = open(fname,O_RDWR|O_CREAT, 0600);
-
-	if (fd == -1) {
-		return 0;
-	}
-
-	if (!lock_file(fd)) {
-		rprintf(FERROR,"failed to lock %s\n", fname);
-		close(fd);
-		return 0;
-	}
-
-	/* find a free spot */
-	for (i=0;i<max_connections;i++) {
-		if (read(fd,&pid,sizeof(pid)) != sizeof(pid)) break;
-		if (pid == 0 || !process_exists(pid)) break;
-	}		
 
-	if (i == max_connections) {
-		unlock_file(fd);
-		close(fd);
-		return 0;
-	}
-
-	pid = getpid();
-
-	if (lseek(fd,i*sizeof(pid),SEEK_SET) != i*sizeof(pid) ||
-	    write(fd, &pid,sizeof(pid)) != sizeof(pid)) {
-		unlock_file(fd);
-		close(fd);
-		return 0;
-	}
-
-	unlock_file(fd);
-	close(fd);
-	return 1;
+	/* A lock failure needs to return an errno of 0. */
+	errno = 0;
+	return 0;
 }