Add s6-dns-hosts-compile, prepare for 2.3.6.0

Signed-off-by: Laurent Bercot <ska@appnovation.com>

1 files changed, 62 insertions, 0 deletions

diff --git a/src/libs6dns/s6dns_hosts_init.c b/src/libs6dns/s6dns_hosts_init.c
new file mode 100644
index 0000000..d3cd863
--- /dev/null
+++ b/src/libs6dns/s6dns_hosts_init.c
@@ -0,0 +1,62 @@
+/* ISC license. */
+
+#include <unistd.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+
+#include <skalibs/posixplz.h>
+#include <skalibs/cdb.h>
+#include <skalibs/djbunix.h>
+
+#include <s6-dns/hosts.h>
+
+int s6dns_hosts_init (void)
+{
+  int fdr, fdw ;
+  char tmp[24] = "/tmp/hosts.cdb:XXXXXX" ;
+  int fdc = openc_read("/etc/hosts.cdb") ;
+  if (fdc >= 0)
+  {
+    struct stat stc, str ;
+    if (fstat(fdc, &stc) == -1) goto errc ;
+    if (stat("/etc/hosts", &str) == -1)
+    {
+      if (errno == ENOENT) goto useit ;
+      else goto errc ;
+    }
+    if (stc.st_mtim > str.st_mtim) goto useit ;
+    fd_close(fdc) ;
+  }
+  fdr = openc_read("/etc/hosts") ;
+  if (fdr == -1) return errno == ENOENT ? (errno = 0, 0) : -1 ;
+  fdw = mkstemp(tmp) ;
+  if (fdw == -1) goto errr ;
+  if (!s6dns_hosts_compile(fdr, fdw)) goto errw ;
+  if (lseek(fdw, 0, SEEK_SET) == -1) goto errw ;
+  if (!cdb_init_fromfd(&s6dns_hosts_here, fdw)) goto errw ;
+  fd_close(fdw) ;
+  unlink_void(tmp) ;
+  fd_close(fdr) ;
+  return 1 ;
+
+ errw:
+  fd_close(fdw) ;
+  unlink_void(tmp) ;
+ errr:
+  fd_close(fdr) ;
+  return -1 ;
+
+ errc:
+  fd_close(fdc) ;
+  return -1 ;
+
+ useit:
+  if (!cdb_init_fromfd(&s6dns_hosts_here, fdc))
+  {
+    fd_close(fdc) ;
+    return 0 ;
+  }
+  fd_close(fdc) ;
+  return 1 ;
+}