- keep track of the nesting level

- be pickier about parsing numbers
- only report as JSON objects and arrays; not plain elements.

diff --git a/src/is_json.c b/src/is_json.c
index f0710e1c9920199f11daca8bb79e06278d53aead..98ea28f5f0196f3f60f5e8b7d53059433b10d079 100644 (file)
--- a/src/is_json.c
+++ b/src/is_json.c
@@ -28,13 +28,15 @@
  * Parse JSON object serialization format (RFC-7159)
  */
 
+#ifndef TEST
 #include "file.h"
 
 #ifndef lint
-FILE_RCSID("@(#)$File: is_json.c,v 1.2 2018/08/11 11:06:19 christos Exp $")
+FILE_RCSID("@(#)$File: is_json.c,v 1.3 2018/08/11 12:05:24 christos Exp $")
 #endif
 
 #include "magic.h"
+#endif
 
 #ifdef DEBUG
 #include <stdio.h>
@@ -44,7 +46,7 @@ FILE_RCSID("@(#)$File: is_json.c,v 1.2 2018/08/11 11:06:19 christos Exp $")
 #define DPRINTF(a, b, c)       (void)0
 #endif
 
-static int json_parse(const unsigned char **, const unsigned char *);
+static int json_parse(const unsigned char **, const unsigned char *, int);
 
 static int
 json_isspace(const unsigned char uc)
@@ -144,13 +146,13 @@ out:
 }
 
 static int
-json_parse_array(const unsigned char **ucp, const unsigned char *ue)
+json_parse_array(const unsigned char **ucp, const unsigned char *ue, int lvl)
 {
        const unsigned char *uc = *ucp;
 
        DPRINTF("Parse array: ", uc, *ucp);
        while (uc < ue) {
-               if (!json_parse(&uc, ue))
+               if (!json_parse(&uc, ue, lvl + 1))
                        goto out;
                switch (*uc) {
                case ',':
@@ -170,7 +172,7 @@ out:
 }
 
 static int
-json_parse_object(const unsigned char **ucp, const unsigned char *ue)
+json_parse_object(const unsigned char **ucp, const unsigned char *ue, int lvl)
 {
        const unsigned char *uc = *ucp;
        DPRINTF("Parse object: ", uc, *ucp);
@@ -194,7 +196,7 @@ json_parse_object(const unsigned char **ucp, const unsigned char *ue)
                        DPRINTF("not colon", uc, *ucp);
                        goto out;
                }
-               if (!json_parse(&uc, ue)) {
+               if (!json_parse(&uc, ue, lvl + 1)) {
                        DPRINTF("not json", uc, *ucp);
                        goto out;
                }
@@ -221,6 +223,7 @@ static int
 json_parse_number(const unsigned char **ucp, const unsigned char *ue)
 {
        const unsigned char *uc = *ucp;
+       int got = 0;
 
        DPRINTF("Parse number: ", uc, *ucp);
        if (uc == ue)
@@ -231,28 +234,34 @@ json_parse_number(const unsigned char **ucp, const unsigned char *ue)
        for (; uc < ue; uc++) {
                if (!json_isdigit(*uc))
                        break;
+               got = 1;
        }
        if (*uc == '.')
                uc++;
        for (; uc < ue; uc++) {
                if (!json_isdigit(*uc))
                        break;
+               got = 1;
        }
-       if (*uc == 'e' || *uc == 'E')
-               uc++;
-       if (*uc == '+' || *uc == '-')
-               uc++;
-       for (; uc < ue; uc++) {
-               if (!json_isdigit(*uc))
-                       break;
+       if (got) {
+               got = 0;
+               if (*uc == 'e' || *uc == 'E')
+                       uc++;
+               if (*uc == '+' || *uc == '-')
+                       uc++;
+               for (; uc < ue; uc++) {
+                       if (!json_isdigit(*uc))
+                               break;
+                       got = 1;
+               }
        }
        ue = *ucp;
-       if (uc == ue)
+       if (!got || uc == ue)
                DPRINTF("Bad number: ", uc, *ucp);
        else
                DPRINTF("Good number: ", uc, *ucp);
        *ucp = uc;
-       return uc != ue;
+       return uc != ue && got;
 }
                
 static int
@@ -273,10 +282,10 @@ json_parse_const(const unsigned char **ucp, const unsigned char *ue,
 }
 
 static int
-json_parse(const unsigned char **ucp, const unsigned char *ue)
+json_parse(const unsigned char **ucp, const unsigned char *ue, int lvl)
 {
-       int rv = 0;
        const unsigned char *uc;
+       int rv = 0, rec = 0;
 
        uc = json_skip_space(*ucp, ue);
        if (uc == ue)
@@ -288,10 +297,12 @@ json_parse(const unsigned char **ucp, const unsigned char *ue)
                rv = json_parse_string(&uc, ue);
                break;
        case '[':
-               rv = json_parse_array(&uc, ue);
+               rv = json_parse_array(&uc, ue, lvl);
+               rec = 1;
                break;
        case '{': /* '}' */
-               rv = json_parse_object(&uc, ue);
+               rv = json_parse_object(&uc, ue, lvl);
+               rec = 1;
                break;
        case 't':
                rv = json_parse_const(&uc, ue, "true", sizeof("true"));
@@ -311,6 +322,8 @@ json_parse(const unsigned char **ucp, const unsigned char *ue)
 out:
        *ucp = uc;
        DPRINTF("End general: ", uc, *ucp);
+       if (lvl == 0)
+               return rv && rec;
        return rv;
 }
 
@@ -325,7 +338,7 @@ file_is_json(struct magic_set *ms, const struct buffer *b)
        if ((ms->flags & (MAGIC_APPLE|MAGIC_EXTENSION)) != 0)
                return 0;
 
-       if (!json_parse(&uc, ue))
+       if (!json_parse(&uc, ue, 0))
                return 0;
 
        if (mime == MAGIC_MIME_ENCODING)
@@ -368,7 +381,7 @@ main(int argc, char *argv[])
                err(EXIT_FAILURE, "Can't read %jd bytes",
                    (intmax_t)st.st_size);
        printf("is json %d\n", json_parse((const unsigned char **)&p,
-           p + st.st_size));
+           p + st.st_size, 0));
        return 0;
 }
 #endif