ga_serv.lc

unix网络编程卷1：套接口API的全书源码

#include    "gai_hdr.h"##  1 ##src/libgai/ga_serv.c##

/*##  2 ##src/libgai/ga_serv.c##
 * This function handles the service string.##  3 ##src/libgai/ga_serv.c##
 */##  4 ##src/libgai/ga_serv.c##

/* include ga_serv */
int##  5 ##src/libgai/ga_serv.c##
ga_serv(struct addrinfo *aihead, const struct addrinfo *hintsp,##  6 ##src/libgai/ga_serv.c##
        const char *serv)##  7 ##src/libgai/ga_serv.c##
{##  8 ##src/libgai/ga_serv.c##
    int     port, rc, nfound;##  9 ##src/libgai/ga_serv.c##
    struct servent *sptr;## 10 ##src/libgai/ga_serv.c##

    nfound = 0;## 11 ##src/libgai/ga_serv.c##
    if (isdigit(serv[0])) {     /* check for port number string first */## 12 ##src/libgai/ga_serv.c##
        port = htons(atoi(serv));## 13 ##src/libgai/ga_serv.c##
        if (hintsp->ai_socktype) {## 14 ##src/libgai/ga_serv.c##
            /* 4caller specifies socket type */## 15 ##src/libgai/ga_serv.c##
            if ((rc = ga_port(aihead, port, hintsp->ai_socktype)) < 0)## 16 ##src/libgai/ga_serv.c##
                return (EAI_MEMORY);## 17 ##src/libgai/ga_serv.c##
            nfound += rc;## 18 ##src/libgai/ga_serv.c##
        } else {## 19 ##src/libgai/ga_serv.c##
            /* 4caller does not specify socket type */## 20 ##src/libgai/ga_serv.c##
            if ((rc = ga_port(aihead, port, SOCK_STREAM)) < 0)## 21 ##src/libgai/ga_serv.c##
                return (EAI_MEMORY);## 22 ##src/libgai/ga_serv.c##
            nfound += rc;## 23 ##src/libgai/ga_serv.c##
            if ((rc = ga_port(aihead, port, SOCK_DGRAM)) < 0)## 24 ##src/libgai/ga_serv.c##
                return (EAI_MEMORY);## 25 ##src/libgai/ga_serv.c##
            nfound += rc;## 26 ##src/libgai/ga_serv.c##
        }## 27 ##src/libgai/ga_serv.c##
    } else {## 28 ##src/libgai/ga_serv.c##
        /* 4try service name, TCP then UDP */## 29 ##src/libgai/ga_serv.c##
        if (hintsp->ai_socktype == 0 || hintsp->ai_socktype == SOCK_STREAM) {## 30 ##src/libgai/ga_serv.c##
            if ((sptr = getservbyname(serv, "tcp")) != NULL) {## 31 ##src/libgai/ga_serv.c##
                if ((rc = ga_port(aihead, sptr->s_port, SOCK_STREAM)) < 0)## 32 ##src/libgai/ga_serv.c##
                    return (EAI_MEMORY);## 33 ##src/libgai/ga_serv.c##
                nfound += rc;## 34 ##src/libgai/ga_serv.c##
            }## 35 ##src/libgai/ga_serv.c##
        }## 36 ##src/libgai/ga_serv.c##
        if (hintsp->ai_socktype == 0 || hintsp->ai_socktype == SOCK_DGRAM) {## 37 ##src/libgai/ga_serv.c##
            if ((sptr = getservbyname(serv, "udp")) != NULL) {## 38 ##src/libgai/ga_serv.c##
                if ((rc = ga_port(aihead, sptr->s_port, SOCK_DGRAM)) < 0)## 39 ##src/libgai/ga_serv.c##
                    return (EAI_MEMORY);## 40 ##src/libgai/ga_serv.c##
                nfound += rc;## 41 ##src/libgai/ga_serv.c##
            }## 42 ##src/libgai/ga_serv.c##
        }## 43 ##src/libgai/ga_serv.c##
    }## 44 ##src/libgai/ga_serv.c##

    if (nfound == 0) {## 45 ##src/libgai/ga_serv.c##
        if (hintsp->ai_socktype == 0)## 46 ##src/libgai/ga_serv.c##
            return (EAI_NONAME);    /* all calls to getservbyname() failed */## 47 ##src/libgai/ga_serv.c##
        else## 48 ##src/libgai/ga_serv.c##
            return (EAI_SERVICE);   /* service not supported for socket type */## 49 ##src/libgai/ga_serv.c##
    }## 50 ##src/libgai/ga_serv.c##
    return (0);## 51 ##src/libgai/ga_serv.c##
}## 52 ##src/libgai/ga_serv.c##
/* end ga_serv */