From 48e0488f079899b451fb0d19923a48e5212bacc7 Mon Sep 17 00:00:00 2001
From: Robert Poor <rdpoor@gmail.com>
Date: Fri, 26 Dec 2014 10:49:15 -0800
Subject: [PATCH 1/2] adding simple-parse example

---
 examples/simple_parse.c | 202 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 202 insertions(+)
 create mode 100644 examples/simple_parse.c

diff --git a/examples/simple_parse.c b/examples/simple_parse.c
new file mode 100644
index 0000000..32745a3
--- /dev/null
+++ b/examples/simple_parse.c
@@ -0,0 +1,202 @@
+/*
+ * Simple example of parsing and printing JSON using jansson.
+ *
+ * SYNOPSIS:
+ * $ examples/simple_parse
+ * Type some JSON > [true, false, null, 1, 0.0, -0.0, "", {"name": "barney"}]
+ * JSON Array of 8 elements:
+ *   JSON True
+ *   JSON False
+ *   JSON Null
+ *   JSON Integer: "1"
+ *   JSON Real: 0.000000
+ *   JSON Real: -0.000000
+ *   JSON String: ""
+ *   JSON Object of 1 pair:
+ *     JSON Key: "name"
+ *     JSON String: "barney"
+ * 
+ * Copyright (c) 2014 Robert Poor <rdpoor@gmail.com>
+ *
+ * Jansson is free software; you can redistribute it and/or modify
+ * it under the terms of the MIT license. See LICENSE for details.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include "jansson.h"
+
+/* forward refs */
+void print_json(json_t *root);
+void print_json_aux(json_t *element, int indent);
+void print_json_indent(int indent);
+const char *json_plural(int count);
+void print_json_object(json_t *element, int indent);
+void print_json_array(json_t *element, int indent);
+void print_json_string(json_t *element, int indent);
+void print_json_integer(json_t *element, int indent);
+void print_json_real(json_t *element, int indent);
+void print_json_true(json_t *element, int indent);
+void print_json_false(json_t *element, int indent);
+void print_json_null(json_t *element, int indent);
+
+void print_json(json_t *root) {
+  print_json_aux(root, 0);
+}
+
+void print_json_aux(json_t *element, int indent) {
+  switch json_typeof(element) {
+    case JSON_OBJECT:
+      print_json_object(element, indent);
+      break;
+    case JSON_ARRAY:
+      print_json_array(element, indent);
+      break;
+    case JSON_STRING:
+      print_json_string(element, indent);
+      break;
+    case JSON_INTEGER:
+      print_json_integer(element, indent);
+      break;
+    case JSON_REAL:
+      print_json_real(element, indent);;
+      break;
+    case JSON_TRUE:
+      print_json_true(element, indent);;
+      break;
+    case JSON_FALSE:
+      print_json_false(element, indent);;
+      break;
+    case JSON_NULL:
+      print_json_null(element, indent);;
+      break;
+    default:
+      fprintf(stderr, "unrecognized JSON type %d\n", json_typeof(element));
+    }
+}
+
+void print_json_indent(int indent) {
+  for (int i=0; i<indent; i++) { putchar(' '); }
+}
+
+const char *json_plural(int count) {
+  return count == 1 ? "" : "s";
+}
+
+void print_json_object(json_t *element, int indent) {
+  print_json_indent(indent);
+  size_t size = json_object_size(element);
+  const char *key;
+  json_t *value;
+
+  printf("JSON Object of %ld pair%s:\n", size, json_plural(size));
+  json_object_foreach(element, key, value) {
+    print_json_indent(indent + 2);
+    printf("JSON Key: \"%s\"\n", key);
+    print_json_aux(value, indent + 2);
+  }
+
+}
+
+void print_json_array(json_t *element, int indent) {
+  print_json_indent(indent);
+  size_t size = json_array_size(element);
+
+  printf("JSON Array of %ld element%s:\n", size, json_plural(size));
+  for (size_t i=0; i<size; i++) {
+    print_json_aux(json_array_get(element, i), indent + 2);
+  }
+}
+
+void print_json_string(json_t *element, int indent) {
+  print_json_indent(indent);
+  printf("JSON String: \"%s\"\n", json_string_value(element));
+}
+
+void print_json_integer(json_t *element, int indent) {
+  print_json_indent(indent);
+  printf("JSON Integer: \"%" JSON_INTEGER_FORMAT "\"\n", json_integer_value(element));
+}
+
+void print_json_real(json_t *element, int indent) {
+  print_json_indent(indent);
+  printf("JSON Real: %f\n", json_real_value(element));
+}
+
+void print_json_true(json_t *element, int indent) {
+  print_json_indent(indent);
+  printf("JSON True\n");
+}
+
+void print_json_false(json_t *element, int indent) {
+  print_json_indent(indent);
+  printf("JSON False\n");
+}
+
+void print_json_null(json_t *element, int indent) {
+  print_json_indent(indent);
+  printf("JSON Null\n");
+}
+
+/* 
+ * Parse text into a JSON object. If text is valid JSON, returns a
+ * json_t structure, otherwise prints and error and returns null.
+ */
+json_t *load_json(const char *text) {
+  json_t *root;
+  json_error_t error;
+
+  root = json_loads(text, 0, &error);
+
+  if (root) {
+    return root;
+  } else {
+    fprintf(stderr, "json error on line %d: %s\n", error.line, error.text);
+    return (json_t *)0;
+  }
+}
+
+/*
+ * Print a prompt and return (by reference) a null-terminated line of
+ * text.  Returns the number of characters read, including the line
+ * termination char but excluding the null.
+ */
+int read_line(char **line) {
+  size_t len = 0;               /* ignored */
+
+  if (*line != NULL) {
+    free(*line);
+    *line = NULL;
+  }
+  printf("Type some JSON > ");
+  fflush(stdout);
+
+  return getline(line, &len, stdin);  
+}
+
+/* ================================================================
+ * main
+ */
+
+int main(int argc, char *argv[]) {
+  char *line = NULL;
+  
+  if (argc != 1) {
+    fprintf(stderr, "Usage: %s\n", argv[0]);
+    exit(-1);
+  }
+
+  while (read_line(&line) > 1) {
+
+    /* parse text into JSON structure */
+    json_t *root = load_json(line);
+
+    if (root) {
+      /* print and release the JSON structure */
+      print_json(root);         
+      json_decref(root);
+    }
+  }
+
+  return 0;
+}

From 220dcb7be3cd92a63f14d7541217724796407c45 Mon Sep 17 00:00:00 2001
From: Robert Poor <rdpoor@gmail.com>
Date: Mon, 29 Dec 2014 06:22:19 -0800
Subject: [PATCH 2/2] use fgets() rather than getline()

---
 examples/simple_parse.c | 28 +++++++++++-----------------
 1 file changed, 11 insertions(+), 17 deletions(-)

diff --git a/examples/simple_parse.c b/examples/simple_parse.c
index 32745a3..945cf0f 100644
--- a/examples/simple_parse.c
+++ b/examples/simple_parse.c
@@ -59,16 +59,16 @@ void print_json_aux(json_t *element, int indent) {
       print_json_integer(element, indent);
       break;
     case JSON_REAL:
-      print_json_real(element, indent);;
+      print_json_real(element, indent);
       break;
     case JSON_TRUE:
-      print_json_true(element, indent);;
+      print_json_true(element, indent);
       break;
     case JSON_FALSE:
-      print_json_false(element, indent);;
+      print_json_false(element, indent);
       break;
     case JSON_NULL:
-      print_json_null(element, indent);;
+      print_json_null(element, indent);
       break;
     default:
       fprintf(stderr, "unrecognized JSON type %d\n", json_typeof(element));
@@ -158,35 +158,29 @@ json_t *load_json(const char *text) {
 
 /*
  * Print a prompt and return (by reference) a null-terminated line of
- * text.  Returns the number of characters read, including the line
- * termination char but excluding the null.
+ * text.  Returns NULL on eof or some error.
  */
-int read_line(char **line) {
-  size_t len = 0;               /* ignored */
-
-  if (*line != NULL) {
-    free(*line);
-    *line = NULL;
-  }
+char *read_line(char *line, int max_chars) {
   printf("Type some JSON > ");
   fflush(stdout);
-
-  return getline(line, &len, stdin);  
+  return fgets(line, max_chars, stdin);
 }
 
 /* ================================================================
  * main
  */
 
+#define MAX_CHARS 4096
+
 int main(int argc, char *argv[]) {
-  char *line = NULL;
+  char line[MAX_CHARS];
   
   if (argc != 1) {
     fprintf(stderr, "Usage: %s\n", argv[0]);
     exit(-1);
   }
 
-  while (read_line(&line) > 1) {
+  while (read_line(line, MAX_CHARS) != (char *)NULL) {
 
     /* parse text into JSON structure */
     json_t *root = load_json(line);