From 21f0a22072f0543c416c440665bcf75ae09e6233 Mon Sep 17 00:00:00 2001

From: Pino Toscano <ptoscano@redhat.com>

Date: Mon, 12 Feb 2018 11:24:06 +0100

Subject: [PATCH] Switch from YAJL to Jansson

While YAJL mostly works fine, it did not see any active development in

the last 3 years.  OTOH, Jansson is another JSON C implementation, with

a very liberal license, and a much nicer API.

Hence, switch all of libguestfs from YAJL to Jansson:

- configure checks, and buildsystem in general

- packages pulled in the appliance

- actual implementations

- contrib scripts

- documentation

This also makes use of the better APIs available (e.g. json_object_get,

json_array_foreach, and json_object_foreach).  This does not change the

API of our OCaml Yajl module.

(cherry picked from commit bd1c5c9f4dcf38458099db8a0bf4659a07ef055d)

---

 appliance/packagelist.in            |  13 ++--

 builder/Makefile.am                 |   4 +-

 builder/yajl-c.c                    |  66 ++++++++--------

 contrib/p2v/aux-scripts/do-build.sh |   8 +-

 contrib/p2v/build-p2v-iso.sh        |   3 +-

 daemon/Makefile.am                  |   4 +-

 daemon/ldm.c                        | 113 ++++++++++++----------------

 docs/guestfs-building.pod           |   2 +-

 lib/Makefile.am                     |   4 +-

 lib/info.c                          | 113 +++++++++++-----------------

 lib/qemu.c                          |  64 ++++++----------

 m4/guestfs-libraries.m4             |   4 +-

 12 files changed, 168 insertions(+), 230 deletions(-)

diff --git a/appliance/packagelist.in b/appliance/packagelist.in

index 8ded2588a..f92a6ce95 100644

--- a/appliance/packagelist.in

+++ b/appliance/packagelist.in

@@ -35,6 +35,7 @@ ifelse(REDHAT,1,

   hivex

   iproute

   iputils

+  jansson

   kernel

   libcap

   libldm

@@ -51,7 +52,6 @@ ifelse(REDHAT,1,

   systemd              dnl for /sbin/reboot and udevd

   vim-minimal

   xz

-  yajl

   yara

   zfs-fuse

 )

@@ -82,12 +82,12 @@ dnl iproute has been renamed to iproute2

   libc-bin

   libcap2

   libhivex0

+  libjansson4

   libpcre3

   libsystemd0

   libsystemd-id128-0

   libsystemd-journal0

   libtirpc1

-  libyajl2

   libyara3

   linux-image

   dnl syslinux 'suggests' mtools, but in reality it's a hard dependency:

@@ -116,6 +116,7 @@ ifelse(ARCHLINUX,1,

   hivex

   iproute2

   iputils

+  jansson

   libcap

   libtirpc

   linux

@@ -131,7 +132,6 @@ ifelse(ARCHLINUX,1,

   systemd

   vim

   xz

-  yajl

   yara

 )

@@ -153,9 +153,9 @@ ifelse(SUSE,1,

   iputils

   libcap2

   libhivex0

+  libjansson4

   libselinux1

   libtirpc3

-  libyajl2

   libyara3

   mkisofs

   ntfsprogs

@@ -177,6 +177,7 @@ ifelse(FRUGALWARE,1,

   hfsplus

   iproute2

   iputils

+  jansson

   kernel

   libcap

   libtirpc

@@ -188,7 +189,6 @@ ifelse(FRUGALWARE,1,

   systemd

   vim

   xz

-  yajl

   xfsprogs-acl

   xfsprogs-attr

   gptfdisk

@@ -209,9 +209,9 @@ ifelse(MAGEIA,1,

   iproute2

   iputils

   libcap

+  libjansson4

   libldm

   libtirpc

-  libyajl

   dnl syslinux uses mtools without depending on it

   mtools

   nilfs-utils

@@ -224,7 +224,6 @@ ifelse(MAGEIA,1,

   systemd /* for /sbin/reboot and udevd */

   vim-minimal

   xz

-  yajl

 )

 acl

diff --git a/builder/Makefile.am b/builder/Makefile.am

index e5872bdd9..c7b50778a 100644

--- a/builder/Makefile.am

+++ b/builder/Makefile.am

@@ -157,7 +157,7 @@ virt_builder_CFLAGS = \

 	$(LIBLZMA_CFLAGS) \

 	$(LIBTINFO_CFLAGS) \

 	$(LIBXML2_CFLAGS) \

-	$(YAJL_CFLAGS)

+	$(JANSSON_CFLAGS)

 BOBJECTS = $(SOURCES_ML:.ml=.cmo)

 XOBJECTS = $(BOBJECTS:.cmo=.cmx)

@@ -211,7 +211,7 @@ OCAMLCLIBS = \

 	$(LIBCRYPT_LIBS) \

 	$(LIBLZMA_LIBS) \

 	$(LIBXML2_LIBS) \

-	$(YAJL_LIBS) \

+	$(JANSSON_LIBS) \

 	$(LIBINTL) \

 	-lgnu

diff --git a/builder/yajl-c.c b/builder/yajl-c.c

index 3c2402e42..e53755f55 100644

--- a/builder/yajl-c.c

+++ b/builder/yajl-c.c

@@ -23,24 +23,17 @@

 #include <caml/memory.h>

 #include <caml/mlvalues.h>

-#include <yajl/yajl_tree.h>

+#include <jansson.h>

 #include <stdio.h>

 #include <string.h>

-/* GCC can't work out that the YAJL_IS_<foo> test is sufficient to

- * ensure that YAJL_GET_<foo> later doesn't return NULL.

- */

-#if defined(__GNUC__) && __GNUC__ >= 6 /* gcc >= 6 */

-#pragma GCC diagnostic ignored "-Wnull-dereference"

-#endif

-

 #define Val_none (Val_int (0))

 value virt_builder_yajl_tree_parse (value stringv);

 static value

-convert_yajl_value (yajl_val val, int level)

+convert_json_t (json_t *val, int level)

 {

   CAMLparam0 ();

   CAMLlocal4 (rv, lv, v, sv);

@@ -48,46 +41,51 @@ convert_yajl_value (yajl_val val, int level)

   if (level > 20)

     caml_invalid_argument ("too many levels of object/array nesting");

-  if (YAJL_IS_OBJECT (val)) {

-    const size_t len = YAJL_GET_OBJECT(val)->len;

+  if (json_is_object (val)) {

+    const size_t len = json_object_size (val);

     size_t i;

+    const char *key;

+    json_t *jvalue;

     rv = caml_alloc (1, 3);

     lv = caml_alloc_tuple (len);

-    for (i = 0; i < len; ++i) {

+    i = 0;

+    json_object_foreach (val, key, jvalue) {

       v = caml_alloc_tuple (2);

-      sv = caml_copy_string (YAJL_GET_OBJECT(val)->keys[i]);

+      sv = caml_copy_string (key);

       Store_field (v, 0, sv);

-      sv = convert_yajl_value (YAJL_GET_OBJECT(val)->values[i], level + 1);

+      sv = convert_json_t (jvalue, level + 1);

       Store_field (v, 1, sv);

       Store_field (lv, i, v);

+      ++i;

     }

     Store_field (rv, 0, lv);

-  } else if (YAJL_IS_ARRAY (val)) {

-    const size_t len = YAJL_GET_ARRAY(val)->len;

+  } else if (json_is_array (val)) {

+    const size_t len = json_array_size (val);

     size_t i;

+    json_t *jvalue;

     rv = caml_alloc (1, 4);

     lv = caml_alloc_tuple (len);

-    for (i = 0; i < len; ++i) {

-      v = convert_yajl_value (YAJL_GET_ARRAY(val)->values[i], level + 1);

+    json_array_foreach (val, i, jvalue) {

+      v = convert_json_t (jvalue, level + 1);

       Store_field (lv, i, v);

     }

     Store_field (rv, 0, lv);

-  } else if (YAJL_IS_STRING (val)) {

+  } else if (json_is_string (val)) {

     rv = caml_alloc (1, 0);

-    v = caml_copy_string (YAJL_GET_STRING(val));

+    v = caml_copy_string (json_string_value (val));

     Store_field (rv, 0, v);

-  } else if (YAJL_IS_DOUBLE (val)) {

+  } else if (json_is_real (val)) {

     rv = caml_alloc (1, 2);

-    v = caml_copy_double (YAJL_GET_DOUBLE(val));

+    v = caml_copy_double (json_real_value (val));

     Store_field (rv, 0, v);

-  } else if (YAJL_IS_INTEGER (val)) {

+  } else if (json_is_integer (val)) {

     rv = caml_alloc (1, 1);

-    v = caml_copy_int64 (YAJL_GET_INTEGER(val));

+    v = caml_copy_int64 (json_integer_value (val));

     Store_field (rv, 0, v);

-  } else if (YAJL_IS_TRUE (val)) {

+  } else if (json_is_true (val)) {

     rv = caml_alloc (1, 5);

     Store_field (rv, 0, Val_true);

-  } else if (YAJL_IS_FALSE (val)) {

+  } else if (json_is_false (val)) {

     rv = caml_alloc (1, 5);

     Store_field (rv, 0, Val_false);

   } else

@@ -101,21 +99,21 @@ virt_builder_yajl_tree_parse (value stringv)

 {

   CAMLparam1 (stringv);

   CAMLlocal1 (rv);

-  yajl_val tree;

-  char error_buf[256];

+  json_t *tree;

+  json_error_t err;

-  tree = yajl_tree_parse (String_val (stringv), error_buf, sizeof error_buf);

+  tree = json_loads (String_val (stringv), JSON_DECODE_ANY, &err;;

   if (tree == NULL) {

-    char buf[256 + sizeof error_buf];

-    if (strlen (error_buf) > 0)

-      snprintf (buf, sizeof buf, "JSON parse error: %s", error_buf);

+    char buf[256 + JSON_ERROR_TEXT_LENGTH];

+    if (strlen (err.text) > 0)

+      snprintf (buf, sizeof buf, "JSON parse error: %s", err.text);

     else

       snprintf (buf, sizeof buf, "unknown JSON parse error");

     caml_invalid_argument (buf);

   }

-  rv = convert_yajl_value (tree, 1);

-  yajl_tree_free (tree);

+  rv = convert_json_t (tree, 1);

+  json_decref (tree);

   CAMLreturn (rv);

 }

diff --git a/contrib/p2v/aux-scripts/do-build.sh b/contrib/p2v/aux-scripts/do-build.sh

index 5edb53d0e..dd6424bb4 100644

--- a/contrib/p2v/aux-scripts/do-build.sh

+++ b/contrib/p2v/aux-scripts/do-build.sh

@@ -53,8 +53,8 @@ case $osversion in

         # This just forces configure to ignore these missing dependencies.

         export LIBTINFO_CFLAGS=-D_GNU_SOURCE

         export LIBTINFO_LIBS=-lncurses

-        export YAJL_CFLAGS=-D_GNU_SOURCE

-        export YAJL_LIBS=-lyajl

+        export JANSSON_CFLAGS=-D_GNU_SOURCE

+        export JANSSON_LIBS=-ljansson

         # Remove some unsupported flags that the configure script hard codes.

         sed -i -e 's/-fno-strict-overflow//' configure

         sed -i -e 's/-Wno-strict-overflow//' configure

@@ -66,8 +66,8 @@ case $osversion in

         # This just forces configure to ignore these missing dependencies.

         export LIBTINFO_CFLAGS=-D_GNU_SOURCE

         export LIBTINFO_LIBS=-lncurses

-        export YAJL_CFLAGS=-D_GNU_SOURCE

-        export YAJL_LIBS=-lyajl

+        export JANSSON_CFLAGS=-D_GNU_SOURCE

+        export JANSSON_LIBS=-ljansson

         ;;

 esac

diff --git a/contrib/p2v/build-p2v-iso.sh b/contrib/p2v/build-p2v-iso.sh

index c80a1b134..ae25cebc8 100755

--- a/contrib/p2v/build-p2v-iso.sh

+++ b/contrib/p2v/build-p2v-iso.sh

@@ -86,7 +86,6 @@ done

 # Various hacks for different versions of RHEL.

 if=virtio

 netdev=virtio-net-pci

-pkgs="$pkgs,yajl-devel"

 declare -a epel

 case $osversion in

     rhel-5.*|centos-5.*)

@@ -105,10 +104,12 @@ case $osversion in

     rhel-6.*|centos-6.*)

         epel[0]="--run-command"

         epel[1]="yum install -y --nogpgcheck https://dl.fedoraproject.org/pub/epel/epel-release-latest-6.noarch.rpm"

+        pkgs="$pkgs,jansson-devel"

         ;;

     rhel-7.*|centos-7.*)

         epel[0]="--run-command"

         epel[1]="yum install -y --nogpgcheck https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm"

+        pkgs="$pkgs,jansson-devel"

         ;;

 esac

diff --git a/daemon/Makefile.am b/daemon/Makefile.am

index 6240f517d..d9ed5625e 100644

--- a/daemon/Makefile.am

+++ b/daemon/Makefile.am

@@ -218,7 +218,7 @@ guestfsd_LDADD = \

 	camldaemon.o \

 	$(ACL_LIBS) \

 	$(CAP_LIBS) \

-	$(YAJL_LIBS) \

+	$(JANSSON_LIBS) \

 	$(SELINUX_LIBS) \

 	$(AUGEAS_LIBS) \

 	$(HIVEX_LIBS) \

@@ -256,7 +256,7 @@ guestfsd_CFLAGS = \

 	$(AUGEAS_CFLAGS) \

 	$(HIVEX_CFLAGS) \

 	$(SD_JOURNAL_CFLAGS) \

-	$(YAJL_CFLAGS) \

+	$(JANSSON_CFLAGS) \

 	$(PCRE_CFLAGS)

 # Parts of the daemon are written in OCaml.  These are linked into a

diff --git a/daemon/ldm.c b/daemon/ldm.c

index 2f4d2aef3..be4fb9701 100644

--- a/daemon/ldm.c

+++ b/daemon/ldm.c

@@ -25,19 +25,12 @@

 #include <sys/stat.h>

 #include <string.h>

-#include <yajl/yajl_tree.h>

+#include <jansson.h>

 #include "daemon.h"

 #include "actions.h"

 #include "optgroups.h"

-/* GCC can't work out that the YAJL_IS_<foo> test is sufficient to

- * ensure that YAJL_GET_<foo> later doesn't return NULL.

- */

-#if defined(__GNUC__) && GUESTFS_GCC_VERSION >= 60000 /* gcc >= 6 */

-#pragma GCC diagnostic ignored "-Wnull-dereference"

-#endif

-

 int

 optgroup_ldm_available (void)

 {

@@ -72,44 +65,42 @@ do_ldmtool_remove_all (void)

   return 0;

 }

-static yajl_val

+static json_t *

 parse_json (const char *json, const char *func)

 {

-  yajl_val tree;

-  char parse_error[1024];

+  json_t *tree;

+  json_error_t err;

   if (verbose)

     fprintf (stderr, "%s: parsing json: %s\n", func, json);

-  tree = yajl_tree_parse (json, parse_error, sizeof parse_error);

+  tree = json_loads (json, 0, &err;;

   if (tree == NULL) {

     reply_with_error ("parse error: %s",

-                      strlen (parse_error) ? parse_error : "unknown error");

+                      strlen (err.text) ? err.text : "unknown error");

     return NULL;

   }

-  /* Caller should free this by doing 'yajl_tree_free (tree);'. */

+  /* Caller should free this by doing 'json_decref (tree);'. */

   return tree;

 }

 #define TYPE_ERROR ((char **) -1)

 static char **

-json_value_to_string_list (yajl_val node)

+json_value_to_string_list (json_t *node)

 {

   CLEANUP_FREE_STRINGSBUF DECLARE_STRINGSBUF (strs);

-  yajl_val n;

-  size_t i, len;

+  json_t *n;

+  size_t i;

-  if (! YAJL_IS_ARRAY (node))

+  if (!json_is_array (node))

     return TYPE_ERROR;

-  len = YAJL_GET_ARRAY (node)->len;

-  for (i = 0; i < len; ++i) {

-    n = YAJL_GET_ARRAY (node)->values[i];

-    if (! YAJL_IS_STRING (n))

+  json_array_foreach (node, i, n) {

+    if (!json_is_string (n))

       return TYPE_ERROR;

-    if (add_string (&strs, YAJL_GET_STRING (n)) == -1)

+    if (add_string (&strs, json_string_value (n)) == -1)

       return NULL;

   }

   if (end_stringsbuf (&strs) == -1)

@@ -123,14 +114,14 @@ parse_json_get_string_list (const char *json,

                             const char *func, const char *cmd)

 {

   char **ret;

-  yajl_val tree = NULL;

+  json_t *tree = NULL;

   tree = parse_json (json, func);

   if (tree == NULL)

     return NULL;

   ret = json_value_to_string_list (tree);

-  yajl_tree_free (tree);

+  json_decref (tree);

   if (ret == TYPE_ERROR) {

     reply_with_error ("output of '%s' was not a JSON array of strings", cmd);

     return NULL;

@@ -144,43 +135,40 @@ static char *

 parse_json_get_object_string (const char *json, const char *key, int flags,

                               const char *func, const char *cmd)

 {

-  char *str, *ret;

-  yajl_val tree = NULL, node;

-  size_t i, len;

+  const char *str;

+  char *ret;

+  json_t *tree = NULL, *node;

   tree = parse_json (json, func);

   if (tree == NULL)

     return NULL;

-  if (! YAJL_IS_OBJECT (tree))

+  if (!json_is_object (tree))

     goto bad_type;

-  len = YAJL_GET_OBJECT (tree)->len;

-  for (i = 0; i < len; ++i) {

-    if (STREQ (YAJL_GET_OBJECT (tree)->keys[i], key)) {

-      node = YAJL_GET_OBJECT (tree)->values[i];

-

-      if ((flags & GET_STRING_NULL_TO_EMPTY) && YAJL_IS_NULL (node))

-        ret = strdup ("");

-      else {

-        str = YAJL_GET_STRING (node);

-        if (str == NULL)

-          goto bad_type;

-        ret = strdup (str);

-      }

-      if (ret == NULL)

-        reply_with_perror ("strdup");

-

-      yajl_tree_free (tree);

+  node = json_object_get (tree, key);

+  if (node == NULL)

+    goto bad_type;

-      return ret;

-    }

+  if ((flags & GET_STRING_NULL_TO_EMPTY) && json_is_null (node))

+    ret = strdup ("");

+  else {

+    str = json_string_value (node);

+    if (str == NULL)

+      goto bad_type;

+    ret = strndup (str, json_string_length (node));

   }

+  if (ret == NULL)

+    reply_with_perror ("strdup");

+

+  json_decref (tree);

+

+  return ret;

  bad_type:

   reply_with_error ("output of '%s' was not a JSON object "

                     "containing a key '%s' of type string", cmd, key);

-  yajl_tree_free (tree);

+  json_decref (tree);

   return NULL;

 }

@@ -189,33 +177,30 @@ parse_json_get_object_string_list (const char *json, const char *key,

                                    const char *func, const char *cmd)

 {

   char **ret;

-  yajl_val tree, node;

-  size_t i, len;

+  json_t *tree, *node;

   tree = parse_json (json, func);

   if (tree == NULL)

     return NULL;

-  if (! YAJL_IS_OBJECT (tree))

+  if (!json_is_object (tree))

     goto bad_type;

-  len = YAJL_GET_OBJECT (tree)->len;

-  for (i = 0; i < len; ++i) {

-    if (STREQ (YAJL_GET_OBJECT (tree)->keys[i], key)) {

-      node = YAJL_GET_OBJECT (tree)->values[i];

-      ret = json_value_to_string_list (node);

-      if (ret == TYPE_ERROR)

-        goto bad_type;

-      yajl_tree_free (tree);

-      return ret;

-    }

-  }

+  node = json_object_get (tree, key);

+  if (node == NULL)

+    goto bad_type;

+

+  ret = json_value_to_string_list (node);

+  if (ret == TYPE_ERROR)

+    goto bad_type;

+  json_decref (tree);

+  return ret;

  bad_type:

   reply_with_error ("output of '%s' was not a JSON object "

                     "containing a key '%s' of type array of strings",

                     cmd, key);

-  yajl_tree_free (tree);

+  json_decref (tree);

   return NULL;

 }

diff --git a/docs/guestfs-building.pod b/docs/guestfs-building.pod

index d350b1d73..2029429fd 100644

--- a/docs/guestfs-building.pod

+++ b/docs/guestfs-building.pod

@@ -172,7 +172,7 @@ I<Required>.

 I<Required>.

-=item yajl E<ge> 2.0.4

+=item Jansson

 I<Required>.

diff --git a/lib/Makefile.am b/lib/Makefile.am

index 91c4e0a2e..d075174d9 100644

--- a/lib/Makefile.am

+++ b/lib/Makefile.am

@@ -141,7 +141,7 @@ libguestfs_la_CFLAGS = \

 	$(PCRE_CFLAGS) \

 	$(LIBVIRT_CFLAGS) \

 	$(LIBXML2_CFLAGS) \

-	$(YAJL_CFLAGS)

+	$(JANSSON_CFLAGS)

 libguestfs_la_LIBADD = \

 	../common/errnostring/liberrnostring.la \

@@ -152,7 +152,7 @@ libguestfs_la_LIBADD = \

 	$(PCRE_LIBS) \

 	$(LIBVIRT_LIBS) $(LIBXML2_LIBS) \

 	$(SELINUX_LIBS) \

-	$(YAJL_LIBS) \

+	$(JANSSON_LIBS) \

 	../gnulib/lib/libgnu.la \

 	$(GETADDRINFO_LIB) \

 	$(HOSTENT_LIB) \

diff --git a/lib/info.c b/lib/info.c

index 93fadcd39..2eadc1c11 100644

--- a/lib/info.c

+++ b/lib/info.c

@@ -37,53 +37,46 @@

 #include <sys/resource.h>

 #endif

-#include <yajl/yajl_tree.h>

+#include <jansson.h>

 #include "guestfs.h"

 #include "guestfs-internal.h"

 #include "guestfs-internal-actions.h"

 #ifdef HAVE_ATTRIBUTE_CLEANUP

-#define CLEANUP_YAJL_TREE_FREE __attribute__((cleanup(cleanup_yajl_tree_free)))

+#define CLEANUP_JSON_T_DECREF __attribute__((cleanup(cleanup_json_t_decref)))

 static void

-cleanup_yajl_tree_free (void *ptr)

+cleanup_json_t_decref (void *ptr)

 {

-  yajl_tree_free (* (yajl_val *) ptr);

+  json_decref (* (json_t **) ptr);

 }

 #else

-#define CLEANUP_YAJL_TREE_FREE

+#define CLEANUP_JSON_T_DECREF

 #endif

-static yajl_val get_json_output (guestfs_h *g, const char *filename);

+static json_t *get_json_output (guestfs_h *g, const char *filename);

 static void set_child_rlimits (struct command *);

 char *

 guestfs_impl_disk_format (guestfs_h *g, const char *filename)

 {

-  size_t i, len;

-  CLEANUP_YAJL_TREE_FREE yajl_val tree = get_json_output (g, filename);

+  CLEANUP_JSON_T_DECREF json_t *tree = get_json_output (g, filename);

+  json_t *node;

   if (tree == NULL)

     return NULL;

-  if (! YAJL_IS_OBJECT (tree))

+  if (!json_is_object (tree))

     goto bad_type;

-  len = YAJL_GET_OBJECT(tree)->len;

-  for (i = 0; i < len; ++i) {

-    if (STREQ (YAJL_GET_OBJECT(tree)->keys[i], "format")) {

-      const char *str;

-      yajl_val node = YAJL_GET_OBJECT(tree)->values[i];

-      if (YAJL_IS_NULL (node))

-        goto bad_type;

-      str = YAJL_GET_STRING (node);

-      if (str == NULL)

-        goto bad_type;

-      return safe_strdup (g, str); /* caller frees */

-    }

-  }

+  node = json_object_get (tree, "format");

+  if (!json_is_string (node))

+    goto bad_type;

+

+  return safe_strndup (g, json_string_value (node),

+                          json_string_length (node)); /* caller frees */

  bad_type:

   error (g, _("qemu-img info: JSON output did not contain ‘format’ key"));

@@ -93,30 +86,20 @@ guestfs_impl_disk_format (guestfs_h *g, const char *filename)

 int64_t

 guestfs_impl_disk_virtual_size (guestfs_h *g, const char *filename)

 {

-  size_t i, len;

-  CLEANUP_YAJL_TREE_FREE yajl_val tree = get_json_output (g, filename);

+  CLEANUP_JSON_T_DECREF json_t *tree = get_json_output (g, filename);

+  json_t *node;

   if (tree == NULL)

     return -1;

-  if (! YAJL_IS_OBJECT (tree))

+  if (!json_is_object (tree))

     goto bad_type;

-  len = YAJL_GET_OBJECT(tree)->len;

-  for (i = 0; i < len; ++i) {

-    if (STREQ (YAJL_GET_OBJECT(tree)->keys[i], "virtual-size")) {

-      yajl_val node = YAJL_GET_OBJECT(tree)->values[i];

-      if (YAJL_IS_NULL (node))

-        goto bad_type;

-      if (! YAJL_IS_NUMBER (node))

-        goto bad_type;

-      if (! YAJL_IS_INTEGER (node)) {

-        error (g, _("qemu-img info: ‘virtual-size’ is not representable as a 64 bit integer"));

-        return -1;

-      }

-      return YAJL_GET_INTEGER (node);

-    }

-  }

+  node = json_object_get (tree, "virtual-size");

+  if (!json_is_integer (node))

+    goto bad_type;

+

+  return json_integer_value (node);

  bad_type:

   error (g, _("qemu-img info: JSON output did not contain ‘virtual-size’ key"));

@@ -126,29 +109,25 @@ guestfs_impl_disk_virtual_size (guestfs_h *g, const char *filename)

 int

 guestfs_impl_disk_has_backing_file (guestfs_h *g, const char *filename)

 {