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/* include readline */
#include "unp.h"

static int read_cnt;
static char *read_ptr;
static char read_buf[MAXLINE];

static ssize_t
my_read(int fd, char *ptr)
{

 if (read_cnt <= 0) {
again:
  if ( (read_cnt = read(fd, read_buf, sizeof(read_buf))) < 0) {
   if (errno == EINTR)
    goto again;
   return(-1);
  } else if (read_cnt == 0)
   return(0);
  read_ptr = read_buf;
 }

 read_cnt--;
 *ptr = *read_ptr++;
 return(1);
}

ssize_t
readline(int fd, void *vptr, size_t maxlen)
{
 ssize_t n, rc;
 char c, *ptr;

 ptr = vptr;
 for (n = 1; n < maxlen; n++) {
  if ( (rc = my_read(fd, &c)) == 1) {
   *ptr++ = c;
   if (c == '\n')
    break; /* newline is stored, like fgets() */
  } else if (rc == 0) {
   *ptr = 0;
   return(n - 1); /* EOF, n - 1 bytes were read */
  } else
   return(-1);  /* error, errno set by read() */
 }

 *ptr = 0; /* null terminate like fgets() */
 return(n);
}

ssize_t
readlinebuf(void **vptrptr)
{
 if (read_cnt)
  *vptrptr = read_ptr;
 return(read_cnt);
}
/* end readline */

ssize_t
Readline(int fd, void *ptr, size_t maxlen)
{
 ssize_t  n;

 if ( (n = readline(fd, ptr, maxlen)) < 0)
  err_sys("readline error");
 return(n);
}