/* Cache handling for host lookup.
- Copyright (C) 2004-2018 Free Software Foundation, Inc.
+ Copyright (C) 2004-2019 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2004.
#include <sys/mman.h>
#include <resolv/resolv-internal.h>
#include <resolv/resolv_context.h>
-#include <resolv/res_use_inet6.h>
+#include <scratch_buffer.h>
#include "dbg_log.h"
#include "nscd.h"
-#ifdef HAVE_SENDFILE
-# include <kernel-features.h>
-#endif
typedef enum nss_status (*nss_gethostbyname4_r)
no_more = 0;
nip = hosts_database;
- /* Initialize configurations. If we are looking for both IPv4 and
- IPv6 address we don't want the lookup functions to automatically
- promote IPv4 addresses to IPv6 addresses. Therefore, use the
- _no_inet6 variant. */
+ /* Initialize configurations. */
struct resolv_context *ctx = __resolv_context_get ();
- bool enable_inet6 = __resolv_context_disable_inet6 (ctx);
if (ctx == NULL)
no_more = 1;
- size_t tmpbuf6len = 1024;
- char *tmpbuf6 = alloca (tmpbuf6len);
- size_t tmpbuf4len = 0;
- char *tmpbuf4 = NULL;
+ struct scratch_buffer tmpbuf6;
+ scratch_buffer_init (&tmpbuf6);
+ struct scratch_buffer tmpbuf4;
+ scratch_buffer_init (&tmpbuf4);
+ struct scratch_buffer canonbuf;
+ scratch_buffer_init (&canonbuf);
+
int32_t ttl = INT32_MAX;
ssize_t total = 0;
char *key_copy = NULL;
int status[2] = { NSS_STATUS_UNAVAIL, NSS_STATUS_UNAVAIL };
int naddrs = 0;
size_t addrslen = 0;
+
char *canon = NULL;
size_t canonlen;
at = &atmem;
rc6 = 0;
herrno = 0;
- status[1] = DL_CALL_FCT (fct4, (key, &at, tmpbuf6, tmpbuf6len,
+ status[1] = DL_CALL_FCT (fct4, (key, &at,
+ tmpbuf6.data, tmpbuf6.length,
&rc6, &herrno, &ttl));
if (rc6 != ERANGE || (herrno != NETDB_INTERNAL
&& herrno != TRY_AGAIN))
break;
- tmpbuf6 = extend_alloca (tmpbuf6, tmpbuf6len, 2 * tmpbuf6len);
+ if (!scratch_buffer_grow (&tmpbuf6))
+ {
+ rc6 = ENOMEM;
+ break;
+ }
}
if (rc6 != 0 && herrno == NETDB_INTERNAL)
while (1)
{
rc6 = 0;
- status[0] = DL_CALL_FCT (fct, (key, AF_INET6, &th[0], tmpbuf6,
- tmpbuf6len, &rc6, &herrno, &ttl,
+ status[0] = DL_CALL_FCT (fct, (key, AF_INET6, &th[0],
+ tmpbuf6.data, tmpbuf6.length,
+ &rc6, &herrno, &ttl,
&canon));
if (rc6 != ERANGE || herrno != NETDB_INTERNAL)
break;
- tmpbuf6 = extend_alloca (tmpbuf6, tmpbuf6len, 2 * tmpbuf6len);
+ if (!scratch_buffer_grow (&tmpbuf6))
+ {
+ rc6 = ENOMEM;
+ break;
+ }
}
if (rc6 != 0 && herrno == NETDB_INTERNAL)
goto out;
- /* If the IPv6 lookup has been successful do not use the
- buffer used in that lookup, use a new one. */
- if (status[0] == NSS_STATUS_SUCCESS && rc6 == 0)
- {
- tmpbuf4len = 512;
- tmpbuf4 = alloca (tmpbuf4len);
- }
- else
- {
- tmpbuf4len = tmpbuf6len;
- tmpbuf4 = tmpbuf6;
- }
-
/* Next collect IPv4 information. */
while (1)
{
rc4 = 0;
- status[1] = DL_CALL_FCT (fct, (key, AF_INET, &th[1], tmpbuf4,
- tmpbuf4len, &rc4, &herrno,
+ status[1] = DL_CALL_FCT (fct, (key, AF_INET, &th[1],
+ tmpbuf4.data, tmpbuf4.length,
+ &rc4, &herrno,
ttl == INT32_MAX ? &ttl : NULL,
canon == NULL ? &canon : NULL));
if (rc4 != ERANGE || herrno != NETDB_INTERNAL)
break;
- tmpbuf4 = extend_alloca (tmpbuf4, tmpbuf4len, 2 * tmpbuf4len);
+ if (!scratch_buffer_grow (&tmpbuf4))
+ {
+ rc4 = ENOMEM;
+ break;
+ }
}
if (rc4 != 0 && herrno == NETDB_INTERNAL)
cfct = __nss_lookup_function (nip, "getcanonname_r");
if (cfct != NULL)
{
- const size_t max_fqdn_len = 256;
- char *buf = alloca (max_fqdn_len);
char *s;
int rc;
- if (DL_CALL_FCT (cfct, (key, buf, max_fqdn_len, &s,
- &rc, &herrno))
+ if (DL_CALL_FCT (cfct, (key, canonbuf.data, canonbuf.length,
+ &s, &rc, &herrno))
== NSS_STATUS_SUCCESS)
canon = s;
else
addrfamily = AF_INET6;
}
- size_t tmpbuflen = 512;
- char *tmpbuf = alloca (tmpbuflen);
int rc;
while (1)
{
rc = __gethostbyaddr2_r (addr, addrlen, addrfamily,
- &hstent_mem, tmpbuf, tmpbuflen,
+ &hstent_mem,
+ canonbuf.data, canonbuf.length,
&hstent, &herrno, NULL);
if (rc != ERANGE || herrno != NETDB_INTERNAL)
break;
- tmpbuf = extend_alloca (tmpbuf, tmpbuflen,
- tmpbuflen * 2);
+ if (!scratch_buffer_grow (&canonbuf))
+ {
+ rc = ENOMEM;
+ break;
+ }
}
if (rc == 0)
would unnecessarily let the receiver wait. */
assert (fd != -1);
-#ifdef HAVE_SENDFILE
- if (__builtin_expect (db->mmap_used, 1) && !alloca_used)
- {
- assert (db->wr_fd != -1);
- assert ((char *) &dataset->resp > (char *) db->data);
- assert ((char *) dataset - (char *) db->head + total
- <= (sizeof (struct database_pers_head)
- + db->head->module * sizeof (ref_t)
- + db->head->data_size));
-# ifndef __ASSUME_SENDFILE
- ssize_t written;
- written =
-# endif
- sendfileall (fd, db->wr_fd, (char *) &dataset->resp
- - (char *) db->head, dataset->head.recsize);
-# ifndef __ASSUME_SENDFILE
- if (written == -1 && errno == ENOSYS)
- goto use_write;
-# endif
- }
- else
-# ifndef __ASSUME_SENDFILE
- use_write:
-# endif
-#endif
- writeall (fd, &dataset->resp, dataset->head.recsize);
+ writeall (fd, &dataset->resp, dataset->head.recsize);
}
goto out;
}
out:
- __resolv_context_enable_inet6 (ctx, enable_inet6);
__resolv_context_put (ctx);
if (dataset != NULL && !alloca_used)
dh->usable = false;
}
+ scratch_buffer_free (&tmpbuf6);
+ scratch_buffer_free (&tmpbuf4);
+ scratch_buffer_free (&canonbuf);
+
return timeout;
}
projects / thirdparty / glibc.git / blobdiff