daemon: Fix wc* commands to work on absolute symbolic links (RHBZ#579608).

daemon/wc.c

@@ -22,6 +22,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <fcntl.h>
 
 #include "../src/guestfs_protocol.h"
 #include "daemon.h"
@@ -30,19 +31,20 @@
 static int
 wc (const char *flag, const char *path)
 {
-  char *buf;
   char *out, *err;
-  int r;
+  int fd, flags, r;
 
-  /* Make the path relative to /sysroot. */
-  buf = sysroot_path (path);
-  if (!buf) {
-    reply_with_perror ("malloc");
+  CHROOT_IN;
+  fd = open (path, O_RDONLY);
+  CHROOT_OUT;
+
+  if (fd == -1) {
+    reply_with_perror ("wc %s: %s", flag, path);
     return -1;
   }
 
-  r = command (&out, &err, "wc", flag, buf, NULL);
-  free (buf);
+  flags = COMMAND_FLAG_CHROOT_COPY_FILE_TO_STDIN | fd;
+  r = commandf (&out, &err, flags, "wc", flag, NULL);
   if (r == -1) {
     reply_with_error ("wc %s: %s", flag, err);
     free (out);

src/generator.ml

@@ -2838,7 +2838,10 @@ See also: L<mkdtemp(3)>");
 
   ("wc_l", (RInt "lines", [Pathname "path"]), 118, [],
    [InitISOFS, Always, TestOutputInt (
-      [["wc_l"; "/10klines"]], 10000)],
+      [["wc_l"; "/10klines"]], 10000);
+    (* Test for RHBZ#579608, absolute symbolic links. *)
+    InitISOFS, Always, TestOutputInt (
+      [["wc_l"; "/abssymlink"]], 10000)],
    "count lines in a file",
    "\
 This command counts the lines in a file, using the