--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/extern/libmustach/mustach-jansson.c	Wed Mar 15 19:34:00 2023 +0100
@@ -0,0 +1,251 @@
+/*
+ Author: José Bollo <jobol@nonadev.net>
+
+ https://gitlab.com/jobol/mustach
+
+ SPDX-License-Identifier: ISC
+*/
+
+#define _GNU_SOURCE
+
+#include <stdio.h>
+#include <string.h>
+
+#include "mustach.h"
+#include "mustach-wrap.h"
+#include "mustach-jansson.h"
+
+struct expl {
+	json_t *root;
+	json_t *selection;
+	int depth;
+	struct {
+		json_t *cont;
+		json_t *obj;
+		void *iter;
+		int is_objiter;
+		size_t index, count;
+	} stack[MUSTACH_MAX_DEPTH];
+};
+
+static int start(void *closure)
+{
+	struct expl *e = closure;
+	e->depth = 0;
+	e->selection = json_null();
+	e->stack[0].cont = NULL;
+	e->stack[0].obj = e->root;
+	e->stack[0].index = 0;
+	e->stack[0].count = 1;
+	return MUSTACH_OK;
+}
+
+static int compare(void *closure, const char *value)
+{
+	struct expl *e = closure;
+	json_t *o = e->selection;
+	double d;
+	json_int_t i;
+
+	switch (json_typeof(o)) {
+	case JSON_REAL:
+		d = json_number_value(o) - atof(value);
+		return d < 0 ? -1 : d > 0 ? 1 : 0;
+	case JSON_INTEGER:
+		i = (json_int_t)json_integer_value(o) - (json_int_t)atoll(value);
+		return i < 0 ? -1 : i > 0 ? 1 : 0;
+	case JSON_STRING:
+		return strcmp(json_string_value(o), value);
+	case JSON_TRUE:
+		return strcmp("true", value);
+	case JSON_FALSE:
+		return strcmp("false", value);
+	case JSON_NULL:
+		return strcmp("null", value);
+	default:
+		return 1;
+	}
+}
+
+static int sel(void *closure, const char *name)
+{
+	struct expl *e = closure;
+	json_t *o;
+	int i, r;
+
+	if (name == NULL) {
+		o = e->stack[e->depth].obj;
+		r = 1;
+	} else {
+		i = e->depth;
+		while (i >= 0 && !(o = json_object_get(e->stack[i].obj, name)))
+			i--;
+		if (i >= 0)
+			r = 1;
+		else {
+			o = json_null();
+			r = 0;
+		}
+	}
+	e->selection = o;
+	return r;
+}
+
+static int subsel(void *closure, const char *name)
+{
+	struct expl *e = closure;
+	json_t *o;
+	int r;
+
+	o = json_object_get(e->selection, name);
+	r = o != NULL;
+	if (r)
+		e->selection = o;
+	return r;
+}
+
+static int enter(void *closure, int objiter)
+{
+	struct expl *e = closure;
+	json_t *o;
+
+	if (++e->depth >= MUSTACH_MAX_DEPTH)
+		return MUSTACH_ERROR_TOO_DEEP;
+
+	o = e->selection;
+	e->stack[e->depth].is_objiter = 0;
+	if (objiter) {
+		if (!json_is_object(o))
+			goto not_entering;
+		e->stack[e->depth].iter = json_object_iter(o);
+		if (e->stack[e->depth].iter == NULL)
+			goto not_entering;
+		e->stack[e->depth].obj = json_object_iter_value(e->stack[e->depth].iter);
+		e->stack[e->depth].cont = o;
+		e->stack[e->depth].is_objiter = 1;
+	} else if (json_is_array(o)) {
+		e->stack[e->depth].count = json_array_size(o);
+		if (e->stack[e->depth].count == 0)
+			goto not_entering;
+		e->stack[e->depth].cont = o;
+		e->stack[e->depth].obj = json_array_get(o, 0);
+		e->stack[e->depth].index = 0;
+	} else if ((json_is_object(o) && json_object_size(0)) || (!json_is_false(o) && !json_is_null(o))) {
+		e->stack[e->depth].count = 1;
+		e->stack[e->depth].cont = NULL;
+		e->stack[e->depth].obj = o;
+		e->stack[e->depth].index = 0;
+	} else
+		goto not_entering;
+	return 1;
+
+not_entering:
+	e->depth--;
+	return 0;
+}
+
+static int next(void *closure)
+{
+	struct expl *e = closure;
+
+	if (e->depth <= 0)
+		return MUSTACH_ERROR_CLOSING;
+
+	if (e->stack[e->depth].is_objiter) {
+		e->stack[e->depth].iter = json_object_iter_next(e->stack[e->depth].cont, e->stack[e->depth].iter);
+		if (e->stack[e->depth].iter == NULL)
+			return 0;
+		e->stack[e->depth].obj = json_object_iter_value(e->stack[e->depth].iter);
+		return 1;
+	}
+
+	e->stack[e->depth].index++;
+	if (e->stack[e->depth].index >= e->stack[e->depth].count)
+		return 0;
+
+	e->stack[e->depth].obj = json_array_get(e->stack[e->depth].cont, e->stack[e->depth].index);
+	return 1;
+}
+
+static int leave(void *closure)
+{
+	struct expl *e = closure;
+
+	if (e->depth <= 0)
+		return MUSTACH_ERROR_CLOSING;
+
+	e->depth--;
+	return 0;
+}
+
+static int get(void *closure, struct mustach_sbuf *sbuf, int key)
+{
+	struct expl *e = closure;
+	const char *s;
+
+	if (key) {
+		s = e->stack[e->depth].is_objiter
+			? json_object_iter_key(e->stack[e->depth].iter)
+			: "";
+	}
+	else if (json_is_string(e->selection))
+		s = json_string_value(e->selection);
+	else if (json_is_null(e->selection))
+		s = "";
+	else {
+		s = json_dumps(e->selection, JSON_ENCODE_ANY | JSON_COMPACT);
+		if (s == NULL)
+			return MUSTACH_ERROR_SYSTEM;
+		sbuf->freecb = free;
+	}
+	sbuf->value = s;
+	return 1;
+}
+
+const struct mustach_wrap_itf mustach_jansson_wrap_itf = {
+	.start = start,
+	.stop = NULL,
+	.compare = compare,
+	.sel = sel,
+	.subsel = subsel,
+	.enter = enter,
+	.next = next,
+	.leave = leave,
+	.get = get
+};
+
+int mustach_jansson_file(const char *template, size_t length, json_t *root, int flags, FILE *file)
+{
+	struct expl e;
+	e.root = root;
+	return mustach_wrap_file(template, length, &mustach_jansson_wrap_itf, &e, flags, file);
+}
+
+int mustach_jansson_fd(const char *template, size_t length, json_t *root, int flags, int fd)
+{
+	struct expl e;
+	e.root = root;
+	return mustach_wrap_fd(template, length, &mustach_jansson_wrap_itf, &e, flags, fd);
+}
+
+int mustach_jansson_mem(const char *template, size_t length, json_t *root, int flags, char **result, size_t *size)
+{
+	struct expl e;
+	e.root = root;
+	return mustach_wrap_mem(template, length, &mustach_jansson_wrap_itf, &e, flags, result, size);
+}
+
+int mustach_jansson_write(const char *template, size_t length, json_t *root, int flags, mustach_write_cb_t *writecb, void *closure)
+{
+	struct expl e;
+	e.root = root;
+	return mustach_wrap_write(template, length, &mustach_jansson_wrap_itf, &e, flags, writecb, closure);
+}
+
+int mustach_jansson_emit(const char *template, size_t length, json_t *root, int flags, mustach_emit_cb_t *emitcb, void *closure)
+{
+	struct expl e;
+	e.root = root;
+	return mustach_wrap_emit(template, length, &mustach_jansson_wrap_itf, &e, flags, emitcb, closure);
+}
+