Diff: pubnub_json_parse.cpp

Revision:

0:d13755cfb705

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/pubnub_json_parse.cpp	Thu Nov 10 22:20:11 2016 +0000
@@ -0,0 +1,223 @@
+/* -*- c-file-style:"stroustrup"; indent-tabs-mode: nil -*- */
+#include "pubnub_json_parse.h"
+
+#include <string.h>
+
+
+char const* pbjson_skip_whitespace(char const *start, char const *end)
+{
+    for (; start < end; ++start) {
+        switch (*start) {
+        case ' ':
+        case '\t':
+        case '\r':
+        case '\n':
+            break;
+        default:
+            return start;
+        }
+    }
+    return start;
+}
+
+
+char const* pbjson_find_end_string(char const *start, char const *end)
+{
+    bool in_escape = false;
+
+    for (; start < end; ++start) {
+        switch (*start) {
+        case '"':
+            if (!in_escape) {
+                return start;
+            }
+            break;
+        case '\\':
+            in_escape = !in_escape;
+            break;
+        case '\0':
+            return start;
+        default:
+            in_escape = false;
+            break;
+        }
+    }
+
+    return start;
+}
+
+
+char const *pbjson_find_end_primitive(char const *start, char const *end)
+{
+    for (; start < end; ++start) {
+        switch (*start) {
+        case ' ':
+        case '\t':
+        case '\r':
+        case '\n':
+        case ',':
+        case '}':
+        case ']':
+            return start-1;
+        case '\0':
+            return start;
+        default:
+            break;
+        }
+    }
+    return start;
+}
+
+
+char const *pbjson_find_end_complex(char const *start, char const *end)
+{
+    bool in_string = false, in_escape = false;
+    int bracket_level = 0, brace_level = 0;
+    char c;
+    char const *s;
+
+    for (s = start, c = *s; (c != '\0') && (s < end); ++s, c = *s) {
+        if (!in_string) {
+            switch (c) {
+            case '{':
+                ++brace_level;
+                break;
+            case '}':
+                if ((--brace_level == 0) && (0 == bracket_level)) {
+                    return s;
+                }
+                break;
+            case '[':
+                ++bracket_level;
+                break;
+            case ']':
+                if ((--bracket_level == 0) && (0 == brace_level)) {
+                    return s;
+                }
+                break;
+            case '"':
+                in_string = true;
+                in_escape = false;
+                break;
+            default:
+                break;
+            }
+        }
+        else {
+            switch (c) {
+            case '"':
+                if (!in_escape) {
+                    in_string = false;
+                }
+                break;
+            case '\\':
+                in_escape = !in_escape;
+                break;
+            default:
+                in_escape = false;
+                break;
+            }
+        }
+    }
+    return s;
+}
+
+
+char const *pbjson_find_end_element(char const *start, char const *end)
+{
+    switch (*start) {
+    case '"':
+        return pbjson_find_end_string(start+1, end);
+    case '{':
+    case '[':
+        return pbjson_find_end_complex(start, end);
+    default:
+        return pbjson_find_end_primitive(start+1, end);
+    }
+}
+
+
+enum pbjson_object_name_parse_result pbjson_get_object_value(struct pbjson_elem const *p, char const *name, struct pbjson_elem *parsed)
+{
+    char const *s = pbjson_skip_whitespace(p->start, p->end);
+    unsigned name_len = strlen(name);
+    bool found = false;
+    char const *end;
+
+    if (0 == name_len) {
+        return jonmpInvalidKeyName;
+    }
+    if (*s != '{') {
+        return jonmpNoStartCurly;
+    }
+    while (s < p->end) {
+        s = pbjson_skip_whitespace(s+1, p->end);
+        if (s == p->end) {
+            return jonmpKeyMissing;
+        }
+        if (*s != '"') {
+            return jonmpKeyNotString;
+        }
+        end = pbjson_find_end_string(s+1, p->end);
+        if (end == p->end) {
+            return jonmpStringNotTerminated;
+        }
+        if (*end != '"') {
+            return jonmpStringNotTerminated;
+        }
+        found = (end-s-1 == name_len) && (0 == memcmp(s+1, name, name_len));
+        s = pbjson_skip_whitespace(end+1, p->end);
+        if (s == p->end) {
+            return jonmpMissingColon;
+        }
+        if (*s != ':') {
+            return jonmpMissingColon;
+        }
+        s = pbjson_skip_whitespace(s+1, p->end);
+        end = pbjson_find_end_element(s, p->end);
+        if (found) {
+            parsed->start = s;
+            parsed->end = end+1;
+            return jonmpOK;
+        }
+        s = pbjson_skip_whitespace(end+1, p->end);
+        if (*s != ',') {
+            if (*s == '}') {
+                break;
+            }
+            return jonmpMissingValueSeparator;
+        }
+    }
+
+    return (s < p->end) ? jonmpKeyNotFound : jonmpObjectIncomplete;
+}
+
+
+bool pbjson_elem_equals_string(struct pbjson_elem const *e, char const *s)
+{
+    char const *p = e->start;
+    for (p = e->start; p != e->end; ++p, ++s) {
+        if (*p != *s) {
+            return false;
+        }
+    }
+    return *s == '\0';
+}
+
+
+char const *pbjson_object_name_parse_result_2_string(enum pbjson_object_name_parse_result e)
+{
+    switch (e) {
+    case jonmpNoStartCurly: return "No Start Curly";
+    case jonmpKeyMissing: return "Key Missing";
+    case jonmpKeyNotString: return "Key Not String";
+    case jonmpStringNotTerminated: return "String Not Terminated";
+    case jonmpMissingColon: return "Missing Colon";
+    case jonmpObjectIncomplete: return "Object Incomplete";
+    case jonmpMissingValueSeparator: return "Missing Value Separator";
+    case jonmpKeyNotFound: return "Key Not Found";
+    case jonmpInvalidKeyName: return "Invalid Key Name";
+    case jonmpOK: return "OK";
+    default: return "?!?";
+    }
+}