xref: /illumos-kvm-cmd/osdep.c (revision 68396ea9)
1 /*
2  * QEMU low level functions
3  *
4  * Copyright (c) 2003 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <stdarg.h>
27 #include <string.h>
28 #include <errno.h>
29 #include <unistd.h>
30 #include <fcntl.h>
31 
32 /* Needed early for CONFIG_BSD etc. */
33 #include "config-host.h"
34 
35 #if defined(CONFIG_MADVISE) || defined(CONFIG_POSIX_MADVISE)
36 #include <sys/mman.h>
37 #endif
38 
39 #ifdef CONFIG_SOLARIS
40 #include <sys/types.h>
41 #include <sys/statvfs.h>
42 /* See MySQL bug #7156 (http://bugs.mysql.com/bug.php?id=7156) for
43    discussion about Solaris header problems */
44 extern int madvise(caddr_t, size_t, int);
45 #endif
46 
47 #include "qemu-common.h"
48 #include "trace.h"
49 #include "sysemu.h"
50 #include "qemu_socket.h"
51 
qemu_madvise(void * addr,size_t len,int advice)52 int qemu_madvise(void *addr, size_t len, int advice)
53 {
54     if (advice == QEMU_MADV_INVALID) {
55         errno = EINVAL;
56         return -1;
57     }
58 #if defined(CONFIG_MADVISE)
59     return madvise(addr, len, advice);
60 #elif defined(CONFIG_POSIX_MADVISE)
61     return posix_madvise(addr, len, advice);
62 #else
63     errno = EINVAL;
64     return -1;
65 #endif
66 }
67 
68 
69 /*
70  * Opens a file with FD_CLOEXEC set
71  */
qemu_open(const char * name,int flags,...)72 int qemu_open(const char *name, int flags, ...)
73 {
74     int ret;
75     int mode = 0;
76 
77     if (flags & O_CREAT) {
78         va_list ap;
79 
80         va_start(ap, flags);
81         mode = va_arg(ap, int);
82         va_end(ap);
83     }
84 
85 #ifdef O_CLOEXEC
86     ret = open(name, flags | O_CLOEXEC, mode);
87 #else
88     ret = open(name, flags, mode);
89     if (ret >= 0) {
90         qemu_set_cloexec(ret);
91     }
92 #endif
93 
94     return ret;
95 }
96 
97 /*
98  * A variant of write(2) which handles partial write.
99  *
100  * Return the number of bytes transferred.
101  * Set errno if fewer than `count' bytes are written.
102  *
103  * This function don't work with non-blocking fd's.
104  * Any of the possibilities with non-bloking fd's is bad:
105  *   - return a short write (then name is wrong)
106  *   - busy wait adding (errno == EAGAIN) to the loop
107  */
qemu_write_full(int fd,const void * buf,size_t count)108 ssize_t qemu_write_full(int fd, const void *buf, size_t count)
109 {
110     ssize_t ret = 0;
111     ssize_t total = 0;
112 
113     while (count) {
114         ret = write(fd, buf, count);
115         if (ret < 0) {
116             if (errno == EINTR)
117                 continue;
118             break;
119         }
120 
121         count -= ret;
122         buf += ret;
123         total += ret;
124     }
125 
126     return total;
127 }
128 
129 /*
130  * Opens a socket with FD_CLOEXEC set
131  */
qemu_socket(int domain,int type,int protocol)132 int qemu_socket(int domain, int type, int protocol)
133 {
134     int ret;
135 
136 #ifdef SOCK_CLOEXEC
137     ret = socket(domain, type | SOCK_CLOEXEC, protocol);
138     if (ret != -1 || errno != EINVAL) {
139         return ret;
140     }
141 #endif
142     ret = socket(domain, type, protocol);
143     if (ret >= 0) {
144         qemu_set_cloexec(ret);
145     }
146 
147     return ret;
148 }
149 
150 /*
151  * Accept a connection and set FD_CLOEXEC
152  */
qemu_accept(int s,struct sockaddr * addr,socklen_t * addrlen)153 int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
154 {
155     int ret;
156 
157 #ifdef CONFIG_ACCEPT4
158     ret = accept4(s, addr, addrlen, SOCK_CLOEXEC);
159     if (ret != -1 || errno != ENOSYS) {
160         return ret;
161     }
162 #endif
163     ret = accept(s, addr, addrlen);
164     if (ret >= 0) {
165         qemu_set_cloexec(ret);
166     }
167 
168     return ret;
169 }
170