usock.c

   1 #include <sys/types.h>
   2 #include <sys/socket.h>
   3 #include <sys/un.h>
   4 #include <netdb.h>
   5 #include <stdlib.h>
   6 #include <unistd.h>
   7 #include <fcntl.h>
   8 #include <errno.h>
   9 #include <string.h>
  10
  11 #include "usock.h"
  12
  13 int usock(int type, const char *host, const char *service) {
  14         int sock = -1;
  15
  16         if (service && !(type & USOCK_UNIX)) {
  17                 struct addrinfo *result, *rp;
  18
  19                 struct addrinfo hints = {
  20                         .ai_family = (type & USOCK_IPV6ONLY) ? AF_INET6 :
  21                                 (type & USOCK_IPV4ONLY) ? AF_INET : AF_UNSPEC,
  22                         .ai_socktype = ((type & 0xff) == USOCK_TCP)
  23                                 ? SOCK_STREAM : SOCK_DGRAM,
  24                         .ai_flags = AI_ADDRCONFIG
  25                                 | ((type & USOCK_SERVER) ? AI_PASSIVE : 0)
  26                                 | ((type & USOCK_NUMERIC) ? AI_NUMERICHOST : 0),
  27                 };
  28
  29                 if (getaddrinfo(host, service, &hints, &result)) {
  30                         return -1;
  31                 }
  32
  33                 for (rp = result; rp != NULL; rp = rp->ai_next) {
  34                         if ((sock = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol))
  35                         == -1) {
  36                                 continue;
  37                         }
  38
  39                         if (!(type & USOCK_NOCLOEXEC)) {
  40                                 fcntl(sock, F_SETFD, fcntl(sock, F_GETFD) | FD_CLOEXEC);
  41                         }
  42
  43                         if (type & USOCK_NONBLOCK) {
  44                                 fcntl(sock, F_SETFL, fcntl(sock, F_GETFL) | O_NONBLOCK);
  45                         }
  46
  47                         if (type & USOCK_SERVER) {
  48                                 const int one = 1;
  49                                 setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
  50
  51                                 if (!bind(sock, rp->ai_addr, rp->ai_addrlen)
  52                                 && ((type & 0xff) != USOCK_TCP || !listen(sock, SOMAXCONN))) {
  53                                         break;
  54                                 }
  55                         } else {
  56                                 if (!connect(sock, rp->ai_addr, rp->ai_addrlen)
  57                                 || errno == EINPROGRESS) {
  58                                         break;
  59                                 }
  60                         }
  61
  62                         close(sock);
  63                         sock = -1;
  64                 }
  65                 freeaddrinfo(result);
  66         } else {
  67                 struct sockaddr_un sun = {.sun_family = AF_UNIX};
  68                 if (strlen(host) >= sizeof(sun.sun_path)) {
  69                         errno = EINVAL;
  70                         return -1;
  71                 }
  72                 strcpy(sun.sun_path, host);
  73
  74                 if ((sock = socket(AF_UNIX, ((type & 0xff) == USOCK_TCP)
  75                                 ? SOCK_STREAM : SOCK_DGRAM, 0)) == -1) {
  76                         return -1;
  77                 }
  78
  79                 if (!(type & USOCK_NOCLOEXEC)) {
  80                         fcntl(sock, F_SETFD, fcntl(sock, F_GETFD) | FD_CLOEXEC);
  81                 }
  82
  83                 if (type & USOCK_NONBLOCK) {
  84                         fcntl(sock, F_SETFL, fcntl(sock, F_GETFL) | O_NONBLOCK);
  85                 }
  86
  87                 if (type & USOCK_SERVER) {
  88                         if (bind(sock, (struct sockaddr*)&sun, sizeof(sun)) ||
  89                         ((type & 0xff) == USOCK_TCP && listen(sock, SOMAXCONN))) {
  90                                 close(sock);
  91                                 return -1;
  92                         }
  93                 } else {
  94                         if (connect(sock, (struct sockaddr*)&sun, sizeof(sun))
  95                         && errno != EINPROGRESS) {
  96                                 close(sock);
  97                                 return -1;
  98                         }
  99                 }
 100         }
 101         return sock;
 102 }