libjson: added printing support (thanks spew)

2 files changed, 95 insertions, 1 deletions

diff --git a/sys/src/libjson/mkfile b/sys/src/libjson/mkfile
index 3b61d9c89..016c2c021 100644
--- a/sys/src/libjson/mkfile
+++ b/sys/src/libjson/mkfile
@@ -2,7 +2,8 @@
 
 LIB=/$objtype/lib/libjson.a
 OFILES=\
-	json.$O
+	json.$O\
+	printjson.$O
 
 HFILES=\
 	/sys/include/json.h
diff --git a/sys/src/libjson/printjson.c b/sys/src/libjson/printjson.c
new file mode 100644
index 000000000..aa6d52485
--- /dev/null
+++ b/sys/src/libjson/printjson.c
@@ -0,0 +1,93 @@
+#include <u.h>
+#include <libc.h>
+#include <json.h>
+
+static int printjson(Fmt*, JSON*, int);
+static int printarray(Fmt*, JSON*, int);
+static int printobject(Fmt*, JSON*, int);
+
+static int
+printarray(Fmt *f, JSON *j, int indent)
+{
+	JSONEl *jl;
+	int i, r;
+
+	if(j->first == nil){
+		return fmtprint(f, "[]");
+	}
+	r = fmtprint(f, "[\n");
+	for(jl = j->first; jl != nil; jl = jl->next){
+		for(i = 0; i < indent; i++)
+			r += fmtprint(f, "\t");
+		r += printjson(f, jl->val, indent);
+		r += fmtprint(f, "%s\n", jl->next != nil ? "," : "");
+	}
+	for(i = 0; i < indent-1; i++)
+		r += fmtprint(f, "\t");
+	r += fmtprint(f, "]");
+	return r;
+}
+
+static int
+printobject(Fmt *f, JSON *j, int indent)
+{
+	JSONEl *jl;
+	int i, r;
+
+	if(j->first == nil){
+		return fmtprint(f, "{}");
+	}
+	r = fmtprint(f, "{\n");
+	for(jl = j->first; jl != nil; jl = jl->next){
+		for(i = 0; i < indent; i++)
+			fmtprint(f, "\t");
+		r += fmtprint(f, "\"%s\": ", jl->name);
+		r += printjson(f, jl->val, indent);
+		r += fmtprint(f, "%s\n", jl->next != nil ? "," : "");
+	}
+	for(i = 0; i < indent-1; i++)
+		r += fmtprint(f, "\t");
+	r += fmtprint(f, "}");
+	return r;
+}
+
+static int
+printjson(Fmt *f, JSON *j, int indent)
+{
+	switch(j->t){
+	case JSONNull:
+		return fmtprint(f, "null");
+		break;
+	case JSONBool:
+		return fmtprint(f, "%s", j->n ? "true" : "false");
+		break;
+	case JSONNumber:
+		return fmtprint(f, "%f", j->n);
+		break;
+	case JSONString:
+		return fmtprint(f, "\"%s\"", j->s);
+		break;
+	case JSONArray:
+		return printarray(f, j, indent+1);
+		break;
+	case JSONObject:
+		return printobject(f, j, indent+1);
+		break;
+	}
+	return 0;
+}
+
+int
+JSONfmt(Fmt *f)
+{
+	JSON *j;
+
+	j = va_arg(f->args, JSON*);
+	return printjson(f, j, 0);
+}
+
+void
+JSONfmtinstall(void)
+{
+	fmtinstall('J', JSONfmt);
+}