json-parser · wkz · Sep 9, 2013 · Sep 9, 2013
diff --git a/Makefile.in b/Makefile.in
@@ -5,6 +5,8 @@ prefix = @prefix@
 includedir = $(DESTDIR)@includedir@
 libdir = $(DESTDIR)@libdir@
 
+AR = @AR@
+CC = @CC@
 CFLAGS = @CFLAGS@
 LDFLAGS = @LDFLAGS@
 SRCS = $(wildcard *.c)

diff --git a/README.md b/README.md
@@ -36,3 +36,8 @@ The `type` field of `json_value` is one of:
 * `json_string` (see `u.string.ptr`, `u.string.length`)
 * `json_boolean` (see `u.boolean`)
 * `json_null`
+
+Some higher-level accessors are available, e.g.:
+
+* `json_object_get (obj, key)` can be used to retrieve the value of the specified key.
+* `json_array_for_each (array, idx, elem)` iterates over all items in an array.
diff --git a/configure b/configure
@@ -584,6 +584,7 @@ PACKAGE_URL=''
 ac_subst_vars='LTLIBOBJS
 LIBOBJS
 VERSION_MAJOR
+AR
 OBJEXT
 EXEEXT
 ac_ct_CC
@@ -2525,6 +2526,98 @@ ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
 ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
 ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
+if test -n "$ac_tool_prefix"; then
+  # Extract the first word of "${ac_tool_prefix}ar", so it can be a program name with args.
+set dummy ${ac_tool_prefix}ar; ac_word=$2
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+$as_echo_n "checking for $ac_word... " >&6; }
+if ${ac_cv_prog_AR+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  if test -n "$AR"; then
+  ac_cv_prog_AR="$AR" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  test -z "$as_dir" && as_dir=.
+    for ac_exec_ext in '' $ac_executable_extensions; do
+  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+    ac_cv_prog_AR="${ac_tool_prefix}ar"
+    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+  done
+IFS=$as_save_IFS
+
+fi
+fi
+AR=$ac_cv_prog_AR
+if test -n "$AR"; then
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $AR" >&5
+$as_echo "$AR" >&6; }
+else
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+fi
+
+
+fi
+if test -z "$ac_cv_prog_AR"; then
+  ac_ct_AR=$AR
+  # Extract the first word of "ar", so it can be a program name with args.
+set dummy ar; ac_word=$2
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+$as_echo_n "checking for $ac_word... " >&6; }
+if ${ac_cv_prog_ac_ct_AR+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  if test -n "$ac_ct_AR"; then
+  ac_cv_prog_ac_ct_AR="$ac_ct_AR" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  test -z "$as_dir" && as_dir=.
+    for ac_exec_ext in '' $ac_executable_extensions; do
+  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+    ac_cv_prog_ac_ct_AR="ar"
+    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+  done
+IFS=$as_save_IFS
+
+fi
+fi
+ac_ct_AR=$ac_cv_prog_ac_ct_AR
+if test -n "$ac_ct_AR"; then
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_AR" >&5
+$as_echo "$ac_ct_AR" >&6; }
+else
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+fi
+
+  if test "x$ac_ct_AR" = x; then
+    AR=":"
+  else
+    case $cross_compiling:$ac_tool_warned in
+yes:)
+{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+ac_tool_warned=yes ;;
+esac
+    AR=$ac_ct_AR
+  fi
+else
+  AR="$ac_cv_prog_AR"
+fi
+
 
 # Check whether --enable-debug was given.
 if test "${enable_debug+set}" = set; then :

diff --git a/configure.ac b/configure.ac
@@ -7,6 +7,7 @@ VERSION_MAJOR="1.0"
 AC_CONFIG_MACRO_DIR([m4])
 
 AC_PROG_CC
+AC_CHECK_TOOL(AR, ar, :)
 
 AC_ARG_ENABLE([debug],
 	[AS_HELP_STRING([--enable-debug],

diff --git a/json.c b/json.c
@@ -881,3 +881,31 @@ void json_value_free (json_value * value)
    json_value_free_ex (&settings, value);
 }
 
+char *json_string_get (json_value *str)
+{
+	if (!str || str->type != json_string)
+		return NULL;
+
+	return str->u.string.ptr;
+}
+
+json_value *json_object_get (json_value *obj, char *key)
+{
+	int i;
+
+	if (!obj || obj->type != json_object)
+		return NULL;
+
+	for (i = 0; i < obj->u.object.length; i++) {
+		if (!strcmp (obj->u.object.values[i].name, key))
+			return obj->u.object.values[i].value;
+	}
+
+	return NULL;
+}
+
+char *json_object_get_string (json_value *obj, char *key)
+{
+	json_value *str = json_object_get (obj, key);
+	return json_string_get (str);
+}
diff --git a/json.h b/json.h
@@ -258,6 +258,30 @@ void json_value_free (json_value *);
 void json_value_free_ex (json_settings * settings,
                          json_value *);
 
+/* Retrieve the underlying string of str, returns NULL if str is NULL
+ * or not a string
+ */
+char *json_string_get (json_value *str);
+
+/* Retrieve a value by its key, returns NULL if obj is NULL or not an
+ * object, or key is not in obj.
+ */
+json_value *json_object_get (json_value *obj, char *key);
+
+/* Retrieve s string attribute from an object by its key, returns NULL
+ * if obj is NULL or not an object, or if the key is not in obj or not
+ * a string.
+ */
+char *json_object_get_string (json_value *obj, char *key);
+
+/* Iterate over all elements in the array _arr, binding _idx and _elm
+ * to the corresponding index and value.
+ */
+#define json_array_for_each(_arr, _idx, _elm)                           \
+	if ((_arr) && (_arr)->type == json_array)			\
+		for (*(_idx) = 0, *(_elm) = (_arr)->u.array.values[0];	\
+		     *(_idx) < (_arr)->u.array.length;			\
+		     *(_elm) = (_arr)->u.array.values[++(*(_idx))])
 
 #ifdef __cplusplus
    } /* extern "C" */