reduced down the v1 pattern

README.md

@@ -15,7 +15,7 @@ Parsing this:
 {"foo":"bar","barbar":[1,2,3],"obj":{"a":"b"}}
 ````
 
-Using `at = js0n(json, len, "barbar", &len)` would return an at of `22` and set len to `7`.
+Using `at = js0n("barbr", json, len, &vlen)` would return an at pointing to `[1,2,3]` and set vlen to `7`.
 
 
 ## History

src/js0n.c

@@ -1,4 +1,4 @@
-// by jeremie miller - 2010
+// by jeremie miller - 2014
 // public domain, contributions/improvements welcome via github at https://github.com/quartzjer/js0n
 
 // gcc started warning for the init syntax used here, is not helpful so don't generate the spam, supressing the warning is really inconsistently supported across versions
@@ -10,15 +10,16 @@
 #pragma GCC diagnostic ignored "-Winitializer-overrides"
 #pragma GCC diagnostic ignored "-Woverride-init"
 
-// opportunity to further optimize would be having different jump tables for higher depths
-#define PUSH(i) if(depth == 1) prev = *out++ = ((cur+i) - js)
-#define CAP(i) if(depth == 1) prev = *out++ = ((cur+i) - (js + prev) + 1)
+// opportunity to further optimize would be having different short-cut jump tables for higher depths
+#define PUSH(i) if(depth == 1) prev = ((cur+i) - start)
+#define CAP(i) if(depth == 1) prev = ((cur+i) - (start + prev) + 1)
 
 // this makes a single pass across the json bytes, using each byte as an index into a jump table to build an index and transition state
-int js0n(const unsigned char *js, unsigned int len, unsigned short *out, unsigned int olen)
+char *js0n(char *key, char *json, unsigned int len, unsigned int *vlen)
 {
-	unsigned short prev = 0, *oend;
-	const unsigned char *cur, *end;
+	char *val = 0;
+	unsigned short prev = 0;
+	const unsigned char *cur, *end, *start;
 	int depth=0;
 	int utf8_remain=0;
 	static void *gostruct[] = 
@@ -65,17 +66,18 @@ int js0n(const unsigned char *js, unsigned int len, unsigned short *out, unsigne
 	};
 	void **go = gostruct;
 
-	for(cur=js,end=js+len,oend=out+olen; cur<end && out<oend; cur++)
+	if(!key || !json || !len) return 0;
+
+	for(start=cur=(unsigned char*)json,end=cur+len; cur<end; cur++)
 	{
 			goto *go[*cur];
 			l_loop:;
 	}
 
-  if(out < oend) *out = 0;
-	return depth; // 0 if successful full parse, >0 for incomplete data
+	return val;
 
 	l_bad:
-		return 1;
+		return 0;
 
 	l_up:
 		PUSH(0);

src/js0n.h

@@ -1,3 +1,4 @@
-// pass it a raw json string and length, and it will tag all the key/value offsets in the out argument (size it same as js to be safe)
-// returns 0 if successful, >0 if not
-int js0n(const unsigned char *js, unsigned int len, unsigned short *out, unsigned int olen);
+// pass it a raw json string, length, and key and it will return a pointer to the start of the value
+// if a vlen is given, it will set it to the length, otherwise it will null terminate it
+// returns 0 if not found or any error
+char *js0n(char *key, char *json, unsigned int len, unsigned int *vlen);

test/example.c

@@ -3,25 +3,15 @@
 #include <string.h>
 #include "../src/js0n.h"
 
-void
-ex1()
+void ex1(void)
 {
-	char *s = "{\"foo\":\"bar\",\"barbar\":[1,2,3],\"obj\":{\"a\":\"b\"}}";
+	char *json = "{\"foo\":\"bar\",\"barbar\":[1,2,3],\"obj\":{\"a\":\"b\"}}";
 
-	// 3 keys, 3 values, each with a start and offset --> 12
-	// Plus one for a terminating zero = 13.
-	unsigned short kvpairs[13];
+	printf("parsing '%s'\n", json);
 
-	printf("Parsing '%s'\n", s);
+	char *val = js0n("barbar", json, strlen(json), 0);
 
-	int rc = js0n((unsigned char*) s, strlen(s), kvpairs, 13);
-
-	printf("returned %d\n",rc);
-
-	for (int i = 0; kvpairs[i]; i += 2)
-
-		printf("%d: at %d len %d is %.*s\n", i, 
-			kvpairs[i], kvpairs[i + 1], kvpairs[i + 1], s + kvpairs[i]);
+	printf("returned %s\n",val);
 
 }