added a bit error checking

diff --git a/kson.c b/kson.c
index 8aa8fa1e653bb357987b68b6665467d794537d17..13a1338c536d472a1232332e4fb18d3e6990a168 100644 (file)
--- a/kson.c
+++ b/kson.c
@@ -4,7 +4,7 @@
 #include <stdio.h>
 #include "kson.h"
 
-kson_node_t *kson_parse_core(const char *json, int *_n)
+kson_node_t *kson_parse_core(const char *json, int *_n, int *error, const char **end)
 {
        int *stack = 0, top = 0, max = 0, n_a = 0, m_a = 0, i;
        kson_node_t *a = 0, *u;
@@ -42,6 +42,10 @@ kson_node_t *kson_parse_core(const char *json, int *_n)
                } else if (*p == ']' || *p == '}') {
                        int i, start, t = *p == ']'? -1 : -2;
                        for (i = top - 1; i >= 0 && stack[i] != t; --i);
+                       if (i < 0) { // error: an extra right bracket
+                               *error = KSON_ERR_EXTRA_RIGHT;
+                               break;
+                       }
                        start = i;
                        u = &a[stack[start-1]];
                        u->n = top - 1 - start;
@@ -49,9 +53,13 @@ kson_node_t *kson_parse_core(const char *json, int *_n)
                        for (i = start + 1; i < top; ++i)
                                u->v.child[i - start - 1] = stack[i];
                        u->type = *p == ']'? KSON_TYPE_ANGLE : KSON_TYPE_CURLY;
-                       top = start;
+                       if ((top = start) == 1) break; // completed one object; remaining characters discarded
                } else if (*p == ':') {
-                       if (top > 0) __push_back(-3);
+                       if (top == 0 || stack[top-1] == -3) {
+                               *error = KSON_ERR_NO_KEY;
+                               break;
+                       }
+                       __push_back(-3);
                } else {
                        int c = *p, type = c == '\''? KSON_TYPE_SGL_QUOTE : c == '"'? KSON_TYPE_DBL_QUOTE : KSON_TYPE_NO_QUOTE;
                        char *r;
@@ -77,6 +85,7 @@ kson_node_t *kson_parse_core(const char *json, int *_n)
                        }
                }
        }
+       *end = p;
        for (i = 0; i < n_a; ++i) // for arrays, move key to v.str
                if (a[i].n == 0 && a[i].v.str == 0)
                        a[i].v.str = a[i].key, a[i].key = 0;
@@ -113,10 +122,15 @@ void kson_print_recur(kson_node_t *nodes, kson_node_t *p)
 int main(int argc, char *argv[])
 {
        kson_node_t *nodes;
-       int n_nodes;
-       nodes = kson_parse_core("{'a':1, 'b':[1,'c']}", &n_nodes);
-       kson_print_recur(nodes, &nodes[0]);
-       putchar('\n');
+       int n_nodes, error;
+       const char *end;
+       nodes = kson_parse_core("{'a':1, 'b':[1,'c',true]}", &n_nodes, &error, &end);
+       if (error == 0) {
+               kson_print_recur(nodes, &nodes[0]);
+               putchar('\n');
+       } else {
+               printf("Error code: %d\n", error);
+       }
        return 0;
 }
 #endif

diff --git a/kson.h b/kson.h
index a3702ec5caf20b7df02f732064e178a0d520f750..8f4ee673eb8174c5d34ced45b07e9a121a09b4cd 100644 (file)
--- a/kson.h
+++ b/kson.h
@@ -9,6 +9,10 @@
 #define KSON_TYPE_ANGLE     4
 #define KSON_TYPE_CURLY     5
 
+#define KSON_ERR_EXTRA_LEFT  1
+#define KSON_ERR_EXTRA_RIGHT 2
+#define KSON_ERR_NO_KEY      3
+
 typedef struct {
        uint64_t type:3, n:61;
        char *key;
@@ -22,7 +26,7 @@ typedef struct {
 extern "C" {
 #endif
 
-       kson_node_t *kson_parse_core(const char *json, int *n);
+       kson_node_t *kson_parse_core(const char *json, int *_n, int *error, const char **end);
 
 #ifdef __cplusplus
 }