[18/25] gethostid (Linux variant): Switch to struct scratch_buffer
Commit Message
Previously, extend_alloca was used without alloca accounting,
which could have been problematic with large NSS results.
---
sysdeps/unix/sysv/linux/gethostid.c | 22 ++++++++++++----------
1 file changed, 12 insertions(+), 10 deletions(-)
@@ -64,13 +64,12 @@ sethostid (id)
# include <sys/param.h>
# include <resolv/netdb.h>
# include <netinet/in.h>
+# include <scratch_buffer.h>
long int
gethostid (void)
{
char hostname[MAXHOSTNAMELEN + 1];
- size_t buflen;
- char *buffer;
struct hostent hostbuf, *hp;
int32_t id;
struct in_addr in;
@@ -95,23 +94,26 @@ gethostid (void)
/* This also fails. Return and arbitrary value. */
return 0;
- buflen = 1024;
- buffer = __alloca (buflen);
+ struct scratch_buffer tmpbuf;
+ scratch_buffer_init (&tmpbuf);
/* To get the IP address we need to know the host name. */
- while (__gethostbyname_r (hostname, &hostbuf, buffer, buflen, &hp, &herr)
- != 0
+ while (__gethostbyname_r (hostname, &hostbuf,
+ tmpbuf.data, tmpbuf.length, &hp, &herr) != 0
|| hp == NULL)
if (herr != NETDB_INTERNAL || errno != ERANGE)
- return 0;
+ {
+ scratch_buffer_free (&tmpbuf);
+ return 0;
+ }
else
- /* Enlarge buffer. */
- buffer = extend_alloca (buffer, buflen, 2 * buflen);
+ if (!scratch_buffer_grow (&tmpbuf))
+ return 0;
in.s_addr = 0;
memcpy (&in, hp->h_addr,
(int) sizeof (in) < hp->h_length ? (int) sizeof (in) : hp->h_length);
-
+ scratch_buffer_free (&tmpbuf);
/* For the return value to be not exactly the IP address we do some
bit fiddling. */
return (int32_t) (in.s_addr << 16 | in.s_addr >> 16);