improved max connections code. Now use fcntl instead of flock.
[rsync.git] / connection.c
index fc7c666751f50c5c062a0d0bda6518e45953a13e..1025c8fc615b8817b4685b06306d52e027cca816 100644 (file)
 /* support the max connections option */
 #include "rsync.h"
 
-int yield_connection(char *fname, int max_connections)
-{
-       int fd, i;
-       pid_t mypid=getpid(), pid=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));
-               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;
-       }
-
-       unlock_file(fd);
-       close(fd);
-       return 1;
-}
-
 
 /****************************************************************************
 simple routine to do connection counting
@@ -79,7 +26,6 @@ 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;
@@ -90,34 +36,11 @@ int claim_connection(char *fname,int max_connections)
                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 (lock_range(fd, i*4, 4)) return 1;
        }               
 
-       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;
+       return 0;
 }