json_out: new module for authoring JSON strings.

[ccan] / ccan / json_out / _info

diff --git a/ccan/json_out/_info b/ccan/json_out/_info
new file mode 100644 (file)
index 0000000..fbb4fa5
--- /dev/null
+++ b/ccan/json_out/_info
@@ -0,0 +1,82 @@
+#include "config.h"
+#include <stdio.h>
+#include <string.h>
+
+/**
+ * json_out - Code for creating simple JSON output.
+ *
+ * This code helps you create well-formed JSON strings.
+ *
+ * Author: Rusty Russell <rusty@rustcorp.com.au>
+ * License: BSD-MIT
+ *
+ * Example:
+ *     // Given "a 1 true" outputs {"argv1":"a","argv2":1,"argv3":true}
+ *     // Print arguments as a JSON array.
+ *     #include <ccan/json_out/json_out.h>
+ *     #include <stdio.h>
+ *     #include <string.h>
+ *     #include <unistd.h>
+ *
+ *     // Simplistic test to see if str needs quotes.
+ *     static bool can_be_json_literal(const char *str)
+ *     {
+ *             char *endp;
+ *             if (strtol(str, &endp, 10) != LONG_MIN
+ *                 && endp != str
+ *                 && *endp == '\0')
+ *                     return true;
+ *             return !strcmp(str, "true")
+ *                     || !strcmp(str, "false")
+ *                     || !strcmp(str, "null");
+ *     }
+ *             
+ *     int main(int argc, char *argv[])
+ *     {
+ *             struct json_out *jout = json_out_new(NULL);
+ *             size_t len;
+ *             const char *p;
+ *
+ *             json_out_start(jout, NULL, '{');
+ *             for (int i = 1; i < argc; i++) {
+ *                     char fieldname[80];
+ *                     sprintf(fieldname, "argv%i", i);
+ *                     json_out_add(jout, fieldname,
+ *                                  !can_be_json_literal(argv[i]),
+ *                                  "%s", argv[i]);
+ *             }
+ *             json_out_end(jout, '}');
+ *             // Force appending of \n
+ *             json_out_direct(jout, 1)[0] = '\n';
+ *             json_out_finished(jout);
+ *
+ *             // Now write it out.
+ *             while ((p = json_out_contents(jout, &len)) != NULL) {
+ *                     int i = write(STDOUT_FILENO, p, len);
+ *                     if (i <= 0)
+ *                             exit(1);
+ *                     json_out_consume(jout, i);
+ *             }
+ *
+ *             tal_free(jout);
+ *             return 0;
+ *     }
+ *     
+ */
+int main(int argc, char *argv[])
+{
+       /* Expect exactly one argument */
+       if (argc != 2)
+               return 1;
+
+       if (strcmp(argv[1], "depends") == 0) {
+               printf("ccan/compiler\n");
+               printf("ccan/json_escape\n");
+               printf("ccan/membuf\n");
+               printf("ccan/tal\n");
+               printf("ccan/typesafe_cb\n");
+               return 0;
+       }
+
+       return 1;
+}