alloc.c

UNIX编程高级环境（第二版）的网络套接字部分的程序源码

#include    "db.h"

/* Allocate & initialize a DB structure, and all the buffers it needs  */

DB *
_db_alloc(int namelen)
{
    DB        *db;

            /* Use calloc, to init structure to zero */
    if ( (db = calloc(1, sizeof(DB))) == NULL)
        err_dump("calloc error for DB");

    db->idxfd = db->datfd = -1;                /* descriptors */

        /* Allocate room for the name.
           +5 for ".idx" or ".dat" plus null at end. */

    if ( (db->name = malloc(namelen + 5)) == NULL)
        err_dump("malloc error for name");

        /* Allocate an index buffer and a data buffer.
           +2 for newline and null at end. */

    if ( (db->idxbuf = malloc(IDXLEN_MAX + 2)) == NULL)
        err_dump("malloc error for index buffer");
    if ( (db->datbuf = malloc(DATLEN_MAX + 2)) == NULL)
        err_dump("malloc error for data buffer");

    return(db);
}