لطفا منتظر باشید ...
D.1 unp.h Header
Almost every program in the text includes our unp.h header, shown in Figure D.1. This header includes all the standard system headers that most network programs need, along with some general system headers. It also defines constants such as MAXLINE, ANSI C function prototypes for the functions we define in the text (e.g., readline), and all the wrapper functions we use. We do not show these prototypes.
Figure D.1 Our header unp.h.
lib/unp.h
1 /* Our own header. Tabs are set for 4 spaces, not 8 */
2 #ifndef __unp_h
3 #define __unp_h
4 #include "../config.h" /* configuration options for current OS */
5 /* "../config.h" is generated by configure */
6 /* If anything changes in the following list of #includes, must change
7 acsite.m4 also, for configure's tests. */
8 #include <sys/types.h> /* basic system data types */
9 #include <sys/socket.h> /* basic socket definitions */
10 #include <sys/time.h> /* timeval{} for select() */
11 #include <time.h> /* timespec{} for pselect() */
12 #include <netinet/in.h> /* sockaddr_in{} and other Internet defns */
13 #include <arpa/inet.h> /* inet(3) functions */
14 #include <errno.h>
15 #include <fcntl.h> /* for nonblocking */
16 #include <netdb.h>
17 #include <signal.h>
18 #include <stdio.h>
19 #include <stdlib.h>
20 #include <string.h>
21 #include <sys/stat.h> /* for S_xxx file mode constants */
22 #include <sys/uio.h> /* for iovec{} and readv/writev */
23 #include <unistd.h>
24 #include <sys/wait.h>
25 #include <sys/un.h> /* for Unix domain sockets */
26 #ifdef HAVE_SYS_SELECT_H
27 # include <sys/select.h> /* for convenience */
28 #endif
29 #ifdef HAVE_SYS_SYSCTL_H
30 # include <sys/sysctl.h>
31 #endif
32 #ifdef HAVE_POLL_H
33 # include <poll.h> /* for convenience */
34 #endif
35 #ifdef HAVE_SYS_EVENT_H
36 # include <sys/event.h> /* for kqueue */
37 #endif
38 #ifdef HAVE_STRINGS_H
39 # include <strings.h> /* for convenience */
40 #endif
41 /* Three headers are normally needed for socket/file ioctl's:
42 * <sys/ioctl.h>, <sys/filio.h>, and <sys/sockio.h>.
43 */
44 #ifdef HAVE_SYS_IOCTL_H
45 # include <sys/ioctl.h>
46 #endif
47 #ifdef HAVE_SYS_FILIO_H
48 # include <sys/filio.h>
49 #endif
50 #ifdef HAVE_SYS_SOCKIO_H
51 # include <sys/sockio.h>
52 #endif
53 #ifdef HAVE_PTHREAD_H
54 # include <pthread.h>
55 #endif
56 #ifdef HAVE_NET_IF_DL_H
57 # include <net/if_dl.h>
58 #endif
59 #ifdef HAVE_NETINET_SCTP_H
60 #include <netinet/sctp.h>
61 #endif
62 /* OSF/1 actually disables recv() and send() in <sys/socket.h> */
63 #ifdef __osf__
64 #undef recv
65 #undef send
66 #define recv(a,b,c,d) recvfrom(a,b,c,d,0,0)
67 #define send(a,b,c,d) sendto(a,b,c,d,0,0)
68 #endif
69 #ifndef INADDR_NONE
70 #define INADDR_NONE 0xffffffff /* should have been in <netinet/in.h> */
71 #endif
72 #ifndef SHUT_RD /* these three POSIX names are new */
73 #define SHUT_RD 0 /* shutdown for reading */
74 #define SHUT_WR 1 /* shutdown for writing */
75 #define SHUT_RDWR 2 /* shutdown for reading and writing */
76 #endif
77 #ifndef INET_ADDRSTRLEN
78 #define INET_ADDRSTRLEN 16 /* "ddd.ddd.ddd.ddd\0"
79 1234567890123456 */
80 #endif
81 /* Define following even if IPv6 not supported, so we can always allocate
82 an adequately sized buffer without #ifdefs in the code. */
83 #ifndef INET6_ADDRSTRLEN
84 #define INET6_ADDRSTRLEN 46 /* max size of IPv6 address string:
85 "xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx" or
86 "xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:ddd.ddd.ddd.ddd\0"
87 1234567890123456789012345678901234567890123456 */
88 #endif
89 /* Define bzero() as a macro if it's not in standard C library. */
90 #ifndef HAVE_BZERO
91 #define bzero(ptr,n) memset (ptr, 0, n)
92 #endif
93 /* Older resolvers do not have gethostbyname2() */
94 #ifndef HAVE_GETHOSTBYNAME2
95 #define gethostbyname2(host,family) gethostbyname((host))
96 #endif
97 /* The structure returned by recvfrom_flags() */
98 struct unp_in_pktinfo {
99 struct in_addr ipi_addr; /* dst IPv4 address */
100 int ipi_ifindex; /* received interface index */
101 };
102 /* We need the newer CMSG_LEN() and CMSG_SPACE() macros, but few
103 implementations support them today. These two macros really need
104 an ALIGN() macro, but each implementation does this differently. */
105 #ifndef CMSG_LEN
106 #define CMSG_LEN(size) (sizeof(struct cmsghdr) + (size))
107 #endif
108 #ifndef CMSG_SPACE
109 #define CMSG_SPACE(size) (sizeof(struct cmsghdr) + (size))
110 #endif
111 /* POSIX requires the SUN_LEN() macro, but not all implementations define
112 it (yet). Note that this 4.4BSD macro works regardless whether there is
113 a length field or not. */
114 #ifndef SUN_LEN
115 # define SUN_LEN (su) 116 (sizeof (*(su)) - sizeof ((su)->sun_path) + strlen((su)->sun_path))
117 #endif
118 /* POSIX renames "Unix domain" as "local IPC."
119 Not all systems define AF_LOCAL and PF_LOCAL (yet). */
120 #ifndef AF_LOCAL
121 #define AF_LOCAL AF_UNIX
122 #endif
123 #ifndef PF_LOCAL
124 #define PF_LOCAL PF_UNIX
125 #endif
126 /* POSIX requires that an #include of <poll.h> define INFTIM, but many
127 systems still define it in <sys/stropts.h>. We don't want to include
128 all the STREAMS stuff if it's not needed, so we just define INFTIM here.
129 This is the standard value, but there's no guarantee it is -1. */
130 #ifndef INFTIM
131 #define INFTIM (-1) /* infinite poll timeout */
132 #ifdef HAVE_POLL_H
133 #define INFTIM_UNPH /* tell unpxti.h we defined it */
134 #endif
135 #endif
136 /* Following could be derived from SOMAXCONN in <sys/socket.h>, but many
137 kernels still #define it as 5, while actually supporting many more */
138 #define LISTENQ 1024 /* 2nd argument to listen () */
139 /* Miscellaneous constants */
140 #define MAXLINE 4096 /* max text line length */
141 #define BUFFSIZE 8192 /* buffer size for reads and writes */
142 /* Define some port number that can be used for our examples */
143 #define SERV_PORT 9877 /* TCP and UDP */
144 #define SERV_PORT_STR "9877" /* TCP and UDP */
145 #define UNIXSTR_PATH "/tmp/unix.str" /* Unix domain stream */
146 #define UNIXDG_PATH "/tmp/unix.dg" /* Unix domain datagram */
147 /* Following shortens all the typecasts of pointer arguments: */
148 #define SA struct sockaddr
149 #define HAVE_STRUCT_SOCKADDR_STORAGE
150 #ifndef HAVE_STRUCT_SOCKADDR_STORAGE
151 /*
152 * RFC 3493: protocol-independent placeholder for socket addresses
153 */
154 #define __SS_MAXSIZE 128
155 #define __SS_ALIGNSIZE (sizeof(int64_t))
156 #ifdef HAVE_SOCKADDR_SA_LEN
157 #define __SS_PAD1SIZE (__SS_ALIGNSIZE - sizeof(u_char) - sizeof(sa_family_t))
158 #else
159 #define __SS_PAD1SIZE (__SS_ALIGNSIZE - sizeof(sa_family_t))
160 #endif
161 #define __SS_PAD2SIZE (__SS_MAXSIZE - 2*__SS_ALIGNSIZE)
162 struct sockaddr_storage {
163 #ifdef HAVE_SOCKADDR_SA_LEN
164 u_char ss_len;
165 #endif
166 sa_family_t ss_family;
167 char __ss_pad1[__SS_PAD1SIZE];
168 int64_t __ss_align;
169 char __ss_pad2[__SS_PAD2SIZE];
170 };
171 #endif
172 #define FILE_MODE (S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)
173 /* default file access permissions for new files */
174 #define DIR_MODE (FILE_MODE | S_IXUSR | S_IXGRP | S_IXOTH)
175 /* default permissions for new directories */
176 typedef void Sigfunc (int); /* for signal handlers */
177 #define min(a,b) ((a) < (b) ? (a) : (b))
178 #define max(a,b) ((a) > (b) ? (a) : (b))
179 #ifndef HAVE_ADDRINFO_STRUCT
180 # include "../lib/addrinfo.h"
181 #endif
182 #ifndef HAVE_IF_NAMEINDEX_STRUCT
183 struct if_nameindex {
184 unsigned int if_index; /* 1, 2, ... */
185 char *if_name; /* null-terminated name: "le0", ... */
186 };
187 #endif
188 #ifndef HAVE_TIMESPEC_STRUCT
189 struct timespec {
190 time_t tv_sec; /* seconds */
191 long tv_nsec; /* and nanoseconds */
192 };
193 #endif
