daemon: Fix head and tail commands to work on absolute symbolic links (RHBZ#579608).

diff --git a/daemon/headtail.c b/daemon/headtail.c
index 9175cf0..164f2b6 100644 (file)
--- a/daemon/headtail.c
+++ b/daemon/headtail.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"
@@ -30,20 +31,21 @@
 static char **
 headtail (const char *prog, const char *flag, const char *n, const char *path)
 {
-  char *buf;
   char *out, *err;
-  int r;
+  int fd, flags, r;
   char **lines;
 
-  /* 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 ("%s", path);
     return NULL;
   }
 
-  r = command (&out, &err, prog, flag, n, buf, NULL);
-  free (buf);
+  flags = COMMAND_FLAG_CHROOT_COPY_FILE_TO_STDIN | fd;
+  r = commandf (&out, &err, flags, prog, flag, n, NULL);
   if (r == -1) {
     reply_with_error ("%s %s %s: %s", prog, flag, n, err);
     free (out);

diff --git a/src/generator.ml b/src/generator.ml
index ffdfb18..d23a8ae 100755 (executable)
--- a/src/generator.ml
+++ b/src/generator.ml
@@ -2859,7 +2859,10 @@ C<wc -c> external command.");
 
   ("head", (RStringList "lines", [Pathname "path"]), 121, [ProtocolLimitWarning],
    [InitISOFS, Always, TestOutputList (
-      [["head"; "/10klines"]], ["0abcdefghijklmnopqrstuvwxyz";"1abcdefghijklmnopqrstuvwxyz";"2abcdefghijklmnopqrstuvwxyz";"3abcdefghijklmnopqrstuvwxyz";"4abcdefghijklmnopqrstuvwxyz";"5abcdefghijklmnopqrstuvwxyz";"6abcdefghijklmnopqrstuvwxyz";"7abcdefghijklmnopqrstuvwxyz";"8abcdefghijklmnopqrstuvwxyz";"9abcdefghijklmnopqrstuvwxyz"])],
+      [["head"; "/10klines"]], ["0abcdefghijklmnopqrstuvwxyz";"1abcdefghijklmnopqrstuvwxyz";"2abcdefghijklmnopqrstuvwxyz";"3abcdefghijklmnopqrstuvwxyz";"4abcdefghijklmnopqrstuvwxyz";"5abcdefghijklmnopqrstuvwxyz";"6abcdefghijklmnopqrstuvwxyz";"7abcdefghijklmnopqrstuvwxyz";"8abcdefghijklmnopqrstuvwxyz";"9abcdefghijklmnopqrstuvwxyz"]);
+    (* Test for RHBZ#579608, absolute symbolic links. *)
+    InitISOFS, Always, TestOutputList (
+      [["head"; "/abssymlink"]], ["0abcdefghijklmnopqrstuvwxyz";"1abcdefghijklmnopqrstuvwxyz";"2abcdefghijklmnopqrstuvwxyz";"3abcdefghijklmnopqrstuvwxyz";"4abcdefghijklmnopqrstuvwxyz";"5abcdefghijklmnopqrstuvwxyz";"6abcdefghijklmnopqrstuvwxyz";"7abcdefghijklmnopqrstuvwxyz";"8abcdefghijklmnopqrstuvwxyz";"9abcdefghijklmnopqrstuvwxyz"])],
    "return first 10 lines of a file",
    "\
 This command returns up to the first 10 lines of a file as