Fix segfault in retagging.

diff --git a/keyutil.c b/keyutil.c
index 6146ae4..269a85d 100644 (file)
--- a/keyutil.c
+++ b/keyutil.c
@@ -1166,7 +1166,9 @@ static int cmd_add(int argc, char *argv[])
     int err;
     key *kk;
     if (k.f & f_retag) {
-      if ((kk = key_bytag(&f, tag)) != 0 && strcmp(kk->tag, tag) == 0)
+      if ((kk = key_bytag(&f, tag)) != 0 &&
+         kk->tag &&
+         strcmp(kk->tag, tag) == 0)
        key_settag(&f, kk, 0);
     }
     if ((err = key_settag(&f, k.k, tag)) != 0)
@@ -1929,6 +1931,8 @@ static int cmd_extract(int argc, char *argv[])
   int i;
   int rc = 0;
   key_filter kf = { 0, 0 };
+  dstr d = DSTR_INIT;
+  const char *outfile = 0;
   FILE *fp;
 
   for (;;) {
@@ -1957,9 +1961,13 @@ static int cmd_extract(int argc, char *argv[])
     die(EXIT_FAILURE, "Usage: extract [-f FILTER] FILE [TAG...]");
   if (strcmp(*argv, "-") == 0)
     fp = stdout;
-  else if (!(fp = fopen(*argv, "w"))) {
-    die(EXIT_FAILURE, "couldn't open `%s' for writing: %s",
-       *argv, strerror(errno));
+  else {
+    outfile = *argv;
+    dstr_putf(&d, "%s.new", outfile);
+    if (!(fp = fopen(d.buf, "w"))) {
+      die(EXIT_FAILURE, "couldn't open `%s' for writing: %s",
+         d.buf, strerror(errno));
+    }
   }
 
   doopen(&f, KOPEN_READ);
@@ -1978,8 +1986,9 @@ static int cmd_extract(int argc, char *argv[])
       }
     }
   }
-  if (fclose(fp))
+  if (fclose(fp) || (outfile && rename(d.buf, outfile)))
     die(EXIT_FAILURE, "error writing file: %s", strerror(errno));
+  dstr_destroy(&d);
   doclose(&f);
   return (rc);
 }