KJSON_PUTDOUBLE(3) Library Functions Manual KJSON_PUTDOUBLE(3)

kjson_putdouble, kjson_putdoublep, kjson_string_putdouble
put floating point content for kcgijson

library “libkcgijson”

#include <sys/types.h>
#include <stdarg.h>
#include <stdint.h>
#include <kcgi.h>
#include <kcgijson.h>

enum kcgi_err
kjson_putdouble(struct kjsonreq *req, double v);

enum kcgi_err
kjson_putdoublep(struct kjsonreq *req, const char *name, double v);

enum kcgi_err
kjson_string_putdouble(struct kjsonreq *req, double v);

Write a double-precision floating point v to a context req initialised with khtml_open(3). This formats the value using the “g” format character of printf(3). If v does not classify as normal, subnormal, or zero, it is output as null.

The kjson_putdouble() form is for array scopes, kjson_putdoublep() is for objects, and kjson_string_putdouble() for open strings.

Passing a NULL value to name for kjson_putdoublep(), is equivalent to calling kjson_putdouble().

Returns an enum kcgi_err indicating the error state.
Success (not an error).
Internal memory allocation failure.
The output connection has been terminated. For FastCGI connections, the current connection should be released with khttp_free(3) and parse loop reentered.
The connection is still expecting headers with khttp_head(3). Indicates that khttp_body(3) did not return with success or was not invoked. For FastCGI connections, the current connection should be released with khttp_free(3) and parse loop reentered.
Internal system error writing to the output stream.
The incorrect form was used for the current scope, for example, an array-type write within an object.

The following outputs a simple JSON document. It assumes r is a struct kreq pointer. For brevity, it does not do any error checking.
khttp_head(r, kresps[KRESP_STATUS],
  "%s", khttps[KHTTP_200]);
khttp_head(r, kresps[KRESP_CONTENT_TYPE],
  "%s", kmimetypes[KMIME_APP_JSON]);
khttp_body(r);
kjson_open(&req, r);
kjson_obj_open(&req);
kjson_putdoublep(&req, "bar", 0.12345);
kjson_arrayp_open(&req, "baz");
kjson_putdouble(&req, (1.0 / 0.0)); /* null */
kjson_close(&req);

kcgijson(3)

Written by Kristaps Dzonsons <kristaps@bsd.lv>.
March 27, 2020 OpenBSD 6.5