src/libstddjb/slurp.c


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/* ISC license. */

#include <sys/types.h>
#include <skalibs/allreadwrite.h>
#include <skalibs/stralloc.h>
#include <skalibs/djbunix.h>

#define N 4096

int slurp (stralloc *sa, int fd)
{
  size_t salen = sa->len ;
  int wasnull = !sa->s ;
  for (;;)
  {
    ssize_t r ;
    if (!stralloc_readyplus(sa, N)) break ;
    r = fd_read(fd, sa->s + sa->len, N) ;
    switch (r)
    {
      case -1: goto err ;
      case 0:
        stralloc_shrink(sa) ;
        return 1 ;
      default:
        sa->len += r ;
    }
  }
err:
  if (wasnull) stralloc_free(sa) ;
  else
  {
    sa->len = salen ;
    stralloc_shrink(sa) ;
  }
  return 0 ;
}