Tweaked some single-line ifs.
[rsync.git] / pipe.c
1 /*  -*- c-file-style: "linux" -*-
2  *
3  * Copyright (C) 1996-2000 by Andrew Tridgell
4  * Copyright (C) Paul Mackerras 1996
5  * Copyright (C) 2001, 2002 by Martin Pool <mbp@samba.org>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  */
21
22 #include "rsync.h"
23
24 extern int am_sender;
25 extern int am_server;
26 extern int blocking_io;
27 extern int orig_umask;
28 extern int read_batch;
29 extern int filesfrom_fd;
30
31 /**
32  * Create a child connected to use on stdin/stdout.
33  *
34  * This is derived from CVS code
35  *
36  * Note that in the child STDIN is set to blocking and STDOUT
37  * is set to non-blocking. This is necessary as rsh relies on stdin being blocking
38  *  and ssh relies on stdout being non-blocking
39  *
40  * If blocking_io is set then use blocking io on both fds. That can be
41  * used to cope with badly broken rsh implementations like the one on
42  * Solaris.
43  **/
44 pid_t piped_child(char **command, int *f_in, int *f_out)
45 {
46         pid_t pid;
47         int to_child_pipe[2];
48         int from_child_pipe[2];
49
50         if (verbose >= 2) {
51                 print_child_argv(command);
52         }
53
54         if (fd_pair(to_child_pipe) < 0 || fd_pair(from_child_pipe) < 0) {
55                 rsyserr(FERROR, errno, "pipe");
56                 exit_cleanup(RERR_IPC);
57         }
58
59         pid = do_fork();
60         if (pid == -1) {
61                 rsyserr(FERROR, errno, "fork");
62                 exit_cleanup(RERR_IPC);
63         }
64
65         if (pid == 0) {
66                 if (dup2(to_child_pipe[0], STDIN_FILENO) < 0 ||
67                     close(to_child_pipe[1]) < 0 ||
68                     close(from_child_pipe[0]) < 0 ||
69                     dup2(from_child_pipe[1], STDOUT_FILENO) < 0) {
70                         rsyserr(FERROR, errno, "Failed to dup/close");
71                         exit_cleanup(RERR_IPC);
72                 }
73                 if (to_child_pipe[0] != STDIN_FILENO)
74                         close(to_child_pipe[0]);
75                 if (from_child_pipe[1] != STDOUT_FILENO)
76                         close(from_child_pipe[1]);
77                 umask(orig_umask);
78                 set_blocking(STDIN_FILENO);
79                 if (blocking_io > 0)
80                         set_blocking(STDOUT_FILENO);
81                 execvp(command[0], command);
82                 rsyserr(FERROR, errno, "Failed to exec %s", command[0]);
83                 exit_cleanup(RERR_IPC);
84         }
85
86         if (close(from_child_pipe[1]) < 0 || close(to_child_pipe[0]) < 0) {
87                 rsyserr(FERROR, errno, "Failed to close");
88                 exit_cleanup(RERR_IPC);
89         }
90
91         *f_in = from_child_pipe[0];
92         *f_out = to_child_pipe[1];
93
94         return pid;
95 }
96
97 pid_t local_child(int argc, char **argv,int *f_in,int *f_out,
98                   int (*child_main)(int, char*[]))
99 {
100         pid_t pid;
101         int to_child_pipe[2];
102         int from_child_pipe[2];
103
104         if (fd_pair(to_child_pipe) < 0 ||
105             fd_pair(from_child_pipe) < 0) {
106                 rsyserr(FERROR, errno, "pipe");
107                 exit_cleanup(RERR_IPC);
108         }
109
110         pid = do_fork();
111         if (pid == -1) {
112                 rsyserr(FERROR, errno, "fork");
113                 exit_cleanup(RERR_IPC);
114         }
115
116         if (pid == 0) {
117                 am_sender = read_batch ? 0 : !am_sender;
118                 am_server = 1;
119
120                 if (!am_sender)
121                         filesfrom_fd = -1;
122
123                 if (dup2(to_child_pipe[0], STDIN_FILENO) < 0 ||
124                     close(to_child_pipe[1]) < 0 ||
125                     close(from_child_pipe[0]) < 0 ||
126                     dup2(from_child_pipe[1], STDOUT_FILENO) < 0) {
127                         rsyserr(FERROR, errno, "Failed to dup/close");
128                         exit_cleanup(RERR_IPC);
129                 }
130                 if (to_child_pipe[0] != STDIN_FILENO)
131                         close(to_child_pipe[0]);
132                 if (from_child_pipe[1] != STDOUT_FILENO)
133                         close(from_child_pipe[1]);
134                 child_main(argc, argv);
135         }
136
137         if (!am_sender)
138                 filesfrom_fd = -1;
139
140         if (close(from_child_pipe[1]) < 0 ||
141             close(to_child_pipe[0]) < 0) {
142                 rsyserr(FERROR, errno, "Failed to close");
143                 exit_cleanup(RERR_IPC);
144         }
145
146         *f_in = from_child_pipe[0];
147         *f_out = to_child_pipe[1];
148
149         return pid;
150 }