Add format tool

A simple command line utility to format JSON data; it allows prettifying
and unprettifying JSON.

1 files changed, 211 insertions, 0 deletions

diff --git a/json-glib/json-glib-format.c b/json-glib/json-glib-format.c
new file mode 100644
index 0000000..df9123b
--- /dev/null
+++ b/json-glib/json-glib-format.c
@@ -0,0 +1,211 @@
+/* json-glib-format - Formats JSON data
+ * 
+ * This file is part of JSON-GLib
+ *
+ * Copyright © 2013  Emmanuele Bassi
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Author:
+ *   Emmanuele Bassi  <ebassi@gnome.org>
+ */
+
+#include "config.h"
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <locale.h>
+#include <errno.h>
+
+#include <glib.h>
+#include <glib/gi18n.h>
+#include <json-glib/json-glib.h>
+
+static char **files = NULL;
+static gboolean prettify = FALSE;
+static int indent_spaces = 2;
+
+static GOptionEntry entries[] = {
+  { "prettify", 'p', 0, G_OPTION_ARG_NONE, &prettify, N_("Prettify output"), NULL },
+  { "indent-spaces", 'i', 0, G_OPTION_ARG_INT, &indent_spaces, N_("Indentation spaces"), NULL },
+  { G_OPTION_REMAINING, 0, 0, G_OPTION_ARG_FILENAME_ARRAY, &files, NULL, NULL },
+  { NULL },
+};
+
+static gboolean
+format (JsonParser    *parser,
+        JsonGenerator *generator,
+        GFile         *file)
+{
+  GInputStream *in;
+  GError *error;
+  gboolean res = TRUE;
+  gboolean parse_res;
+  gboolean close_res;
+  char *data, *p;
+  gsize len;
+
+  error = NULL;
+
+  in = (GInputStream *) g_file_read (file, NULL, &error);
+  if (in == NULL)
+    {
+      /* Translators: the first %s is the program name, the second one
+       * is the URI of the file, the third is the error message.
+       */
+      g_printerr (_("%s: %s: error opening file: %s\n"),
+                  g_get_prgname (), g_file_get_uri (file), error->message);
+      g_error_free (error);
+      return FALSE;
+    }
+
+  parse_res = json_parser_load_from_stream (parser, in, NULL, &error);
+  if (!parse_res)
+    {
+      /* Translators: the first %s is the program name, the second one
+       * is the URI of the file, the third is the error message.
+       */
+      g_printerr (_("%s: %s: error parsing file: %s\n"),
+                  g_get_prgname (), g_file_get_uri (file), error->message);
+      g_clear_error (&error);
+      res = FALSE;
+      goto out;
+    }
+
+  json_generator_set_root (generator, json_parser_get_root (parser));
+  data = json_generator_to_data (generator, &len);
+  p = data;
+  while (len > 0)
+    {
+      ssize_t written = write (STDOUT_FILENO, p, len);
+
+      if (written == -1 && errno != EINTR)
+        {
+          /* Translators: the first %s is the program name, the
+           * second one is the URI of the file.
+           */
+          g_printerr (_("%s: %s, error writing to stdout"), g_get_prgname (), g_file_get_uri (file));
+          res = FALSE;
+          goto out;
+        }
+
+      len -= written;
+      p += written;
+    }
+
+  write (STDOUT_FILENO, "\n", 1);
+
+  g_free (data);
+
+out:
+  close_res = g_input_stream_close (in, NULL, &error);
+  if (!close_res)
+    {
+      /* Translators: the first %s is the program name, the second one
+       * is the URI of the file, the third is the error message.
+       */
+      g_printerr (_("%s: %s:error closing: %s\n"),
+                  g_get_prgname (), g_file_get_uri (file), error->message);
+      g_clear_error (&error);
+      res = FALSE;
+    }
+
+  return res;
+}
+
+int
+main (int   argc,
+      char *argv[])
+{
+  GOptionContext *context = NULL;
+  GError *error = NULL;
+  const char *description;
+  const char *summary;
+  gchar *param;
+  JsonParser *parser;
+  JsonGenerator *generator;
+  gboolean res;
+  int i;
+
+  setlocale (LC_ALL, "");
+
+  bindtextdomain (GETTEXT_PACKAGE, JSON_LOCALEDIR);
+  bind_textdomain_codeset (GETTEXT_PACKAGE, "UTF-8");
+  textdomain (GETTEXT_PACKAGE);
+
+  param = g_strdup_printf (("%s..."), _("FILE"));
+  /* Translators: this message will appear after the usage string */
+  /* and before the list of options.                              */
+  summary = _("Format JSON files.");
+  description = _("json-glib-format formats JSON resources.");
+
+  context = g_option_context_new (param);
+  g_option_context_set_summary (context, summary);
+  g_option_context_set_description (context, description);
+  g_option_context_add_main_entries (context, entries, GETTEXT_PACKAGE);
+  g_option_context_parse (context, &argc, &argv, &error);
+  g_option_context_free (context);
+
+  g_free (param);
+
+  if (error != NULL)
+    {
+      /* Translators: the %s is the program name. This error message
+       * means the user is calling json-glib-validate without any
+       * argument.
+       */
+      g_printerr (_("Error parsing commandline options: %s\n"), error->message);
+      g_printerr ("\n");
+      g_printerr (_("Try \"%s --help\" for more information."), g_get_prgname ());
+      g_printerr ("\n");
+      g_error_free (error);
+      return 1;
+    }
+
+  if (files == NULL)
+    {
+      /* Translators: the %s is the program name. This error message
+       * means the user is calling json-glib-validate without any
+       * argument.
+       */
+      g_printerr (_("%s: missing files"), g_get_prgname ());
+      g_printerr ("\n");
+      g_printerr (_("Try \"%s --help\" for more information."), g_get_prgname ());
+      g_printerr ("\n");
+      return 1;
+    }
+
+  generator = json_generator_new ();
+  json_generator_set_pretty (generator, prettify);
+  json_generator_set_indent (generator, indent_spaces);
+
+  parser = json_parser_new ();
+  res = TRUE;
+  i = 0;
+
+  do
+    {
+      GFile *file = g_file_new_for_commandline_arg (files[i]);
+
+      res = format (parser, generator, file) && res;
+      g_object_unref (file);
+    }
+  while (files[++i] != NULL);
+
+  g_object_unref (parser);
+  g_object_unref (generator);
+
+  return res ? EXIT_SUCCESS : EXIT_FAILURE;
+}