added implementation of json_writer

lib/webfuse_provider/impl/json/writer.c

@@ -1,17 +1,25 @@
 #include "webfuse_provider/impl/json/writer.h"
+#include "webfuse_provider/impl/util/base64.h"
 #include <stdlib.h>
 #include <string.h>
+#include <stdbool.h>
+#include <limits.h>
 
-#define WFP_JSON_WRITER_MAX_LEVEL 8
+#define WFP_JSON_WRITER_MAX_LEVEL 7
+#define WFP_INT_BUFFER_SIZE 64
 
 enum wfp_json_writer_state
 {
-    WFP_JSON_WRITER_STATE_INIT
+    WFP_JSON_WRITER_STATE_INIT,
+    WFP_JSON_WRITER_STATE_ARRAY_FIRST,
+    WFP_JSON_WRITER_STATE_ARRAY_NEXT,
+    WFP_JSON_WRITER_STATE_OBJECT_FIRST,
+    WFP_JSON_WRITER_STATE_OBJECT_NEXT
 };
 
 struct wfp_json_writer
 {
-    enum wfp_json_writer_state state[WFP_JSON_WRITER_MAX_LEVEL];
+    enum wfp_json_writer_state state[WFP_JSON_WRITER_MAX_LEVEL + 1];
     size_t level;
     size_t capacity;
     size_t pre;
@@ -20,6 +28,34 @@ struct wfp_json_writer
     char * raw_data;
 };
 
+static char
+wfp_impl_json_writer_get_esc(
+    char c)
+{
+    switch (c)
+    {
+        case '\\': return '\\';
+        case '\"': return '\"';
+        case '/' : return '/';
+        case '\b': return 'b';
+        case '\f': return 'f';
+        case '\n': return 'n';
+        case '\r': return 'r';
+        case '\t': return 't';
+        default:
+            // error
+            return '/';
+    }
+}
+
+static void
+wfp_impl_json_writer_write_raw_char(
+    struct wfp_json_writer * writer,
+    char value)
+{
+    writer->data[writer->offset++] = value;
+}
+
 static void
 wfp_impl_json_writer_reserve(
     struct wfp_json_writer * writer,
@@ -40,13 +76,47 @@ wfp_impl_json_writer_reserve(
     }
 }
 
-void
-wfp_impl_json_writer_write_raw_char(
-    struct wfp_json_writer * writer,
-    char value)
+static void
+wfp_impl_json_writer_begin_value(
+    struct wfp_json_writer * writer)
 {
-    writer->data[writer->offset] = value;
-    writer->offset++;
+    wfp_impl_json_writer_reserve(writer, 1);
+    if (writer->state[writer->level] == WFP_JSON_WRITER_STATE_ARRAY_NEXT)
+    {
+        wfp_impl_json_writer_write_raw_char(writer, ',');
+    }    
+}
+
+static void
+wfp_impl_json_writer_end_value(
+    struct wfp_json_writer * writer)
+{
+    if (WFP_JSON_WRITER_STATE_ARRAY_FIRST == writer->state[writer->level])
+    {
+        writer->state[writer->level] = WFP_JSON_WRITER_STATE_ARRAY_NEXT;
+    }
+}
+
+static void
+wfp_impl_json_writer_push(
+    struct wfp_json_writer * writer,
+    enum wfp_json_writer_state state)
+{
+    if (writer->level < WFP_JSON_WRITER_MAX_LEVEL)
+    {
+        writer->level++;
+        writer->state[writer->level] = state;
+    }
+}
+
+static void
+wfp_impl_json_writer_pop(
+    struct wfp_json_writer * writer)
+{
+    if (writer->level > 0)
+    {
+        writer->level--;
+    }
 }
 
 void
@@ -84,9 +154,20 @@ wfp_impl_json_writer_dispose(
     free(writer);
 }
 
+void
+wfp_impl_json_writer_reset(
+    struct wfp_json_writer * writer)
+{
+    writer->level = 0;
+    writer->state[writer->level] = WFP_JSON_WRITER_STATE_INIT;
+    writer->offset = 0;
+}
+
+
 char *
 wfp_impl_json_writer_take_data(
-    struct wfp_json_writer * writer)
+    struct wfp_json_writer * writer,
+    size_t * size)
 {
     wfp_impl_json_writer_reserve(writer, 1);    
     writer->data[writer->offset] = '\0';
@@ -94,6 +175,11 @@ wfp_impl_json_writer_take_data(
     char * result = writer->raw_data;
     writer->raw_data = NULL;
 
+    if (NULL != size)
+    {
+        *size = writer->offset;
+    }
+
     return result;
 }
 
@@ -102,7 +188,41 @@ wfp_impl_json_writer_write_int(
     struct wfp_json_writer * writer,
     int value)
 {
+    wfp_impl_json_writer_begin_value(writer);
+    wfp_impl_json_writer_reserve(writer, WFP_INT_BUFFER_SIZE);
 
+    bool const is_signed = (0 > value);
+    char buffer[WFP_INT_BUFFER_SIZE];
+    size_t offset = WFP_INT_BUFFER_SIZE;
+    buffer[--offset] = '\0';
+    if (is_signed) 
+    {
+        if (INT_MIN == value)
+        {
+            char const actual = (char) abs(value % 10);
+            buffer[--offset] = (char) ('0' + actual);
+            value /= 10;
+        }
+        value = -value;
+    }
+
+    do
+    {
+        char const actual = (char) (value % 10);
+        buffer[--offset] = ('0' + actual);
+        value /= 10;
+    }
+    while (0 != value);
+
+    if (is_signed)
+    {
+        buffer[--offset] = '-';
+    }
+
+    size_t const length = (WFP_INT_BUFFER_SIZE - offset - 1);
+    wfp_impl_json_writer_write_raw(writer, &(buffer[offset]), length);
+
+    wfp_impl_json_writer_end_value(writer);
 }
 
 void
@@ -110,6 +230,41 @@ wfp_impl_json_writer_write_string(
     struct wfp_json_writer * writer,
     char const * value)
 {
+    wfp_impl_json_writer_begin_value(writer);
+
+    size_t length = strlen(value);
+    wfp_impl_json_writer_reserve(writer, length + 2);
+
+    wfp_impl_json_writer_write_raw_char(writer, '\"');
+    for(size_t i = 0; i < length; i++)
+    {
+        char c = value[i];
+        if ((' ' <= c) && (c != '\\') && (c != '\"'))
+        {
+            wfp_impl_json_writer_write_raw_char(writer, c);
+        }
+        else
+        {
+            char esc = wfp_impl_json_writer_get_esc(c);
+
+            wfp_impl_json_writer_reserve(writer, (length - i) + 2);
+            wfp_impl_json_writer_write_raw_char(writer, '\\');
+            wfp_impl_json_writer_write_raw_char(writer, esc);
+        }
+        
+    }
+    wfp_impl_json_writer_write_raw_char(writer, '\"');
+
+    wfp_impl_json_writer_end_value(writer);
+}
+
+void
+wfp_impl_json_writer_write_string_nocheck(
+    struct wfp_json_writer * writer,
+    char const * value)
+{
+    wfp_impl_json_writer_begin_value(writer);
+
     size_t length = strlen(value);
     wfp_impl_json_writer_reserve(writer, length + 2);
 
@@ -117,6 +272,7 @@ wfp_impl_json_writer_write_string(
     wfp_impl_json_writer_write_raw(writer, value, length);
     wfp_impl_json_writer_write_raw_char(writer, '\"');
 
+    wfp_impl_json_writer_end_value(writer);
 }
 
 void
@@ -125,14 +281,27 @@ wfp_impl_json_writer_write_bytes(
     char const * data,
     size_t length)
 {
+    wfp_impl_json_writer_begin_value(writer);
 
+    size_t encoded_length = wfp_impl_base64_encoded_size(length);
+    wfp_impl_json_writer_reserve(writer, encoded_length + 2);
+
+    wfp_impl_json_writer_write_raw_char(writer, '\"');
+    wfp_impl_base64_encode((uint8_t const*) data, length, &(writer->data[writer->offset]), encoded_length);
+    writer->offset += encoded_length;
+    wfp_impl_json_writer_write_raw_char(writer, '\"');
+
+    wfp_impl_json_writer_end_value(writer);
 }
 
 void
 wfp_impl_json_writer_object_begin(
     struct wfp_json_writer * writer)
 {
+    wfp_impl_json_writer_begin_value(writer);
     wfp_impl_json_writer_reserve(writer, 1);
+
+    wfp_impl_json_writer_push(writer, WFP_JSON_WRITER_STATE_OBJECT_FIRST);
     wfp_impl_json_writer_write_raw_char(writer, '{');
 }
 
@@ -142,6 +311,9 @@ wfp_impl_json_writer_object_end(
 {
     wfp_impl_json_writer_reserve(writer, 1);
     wfp_impl_json_writer_write_raw_char(writer, '}');
+
+    wfp_impl_json_writer_pop(writer);
+    wfp_impl_json_writer_end_value(writer);
 }
 
 void
@@ -150,13 +322,32 @@ wfp_impl_json_writer_object_key(
     char const * key)
 {
     wfp_impl_json_writer_reserve(writer, 1);
-    wfp_impl_json_writer_write_raw_char(writer, '[');
+
+    size_t length = strlen(key);
+    wfp_impl_json_writer_reserve(writer, length + 4);
+
+    if (WFP_JSON_WRITER_STATE_OBJECT_NEXT == writer->state[writer->level])
+    {
+        wfp_impl_json_writer_write_raw_char(writer, ',');
+    }
+    else
+    {
+        writer->state[writer->level] = WFP_JSON_WRITER_STATE_OBJECT_NEXT;
+    }
+    
+    wfp_impl_json_writer_write_raw_char(writer, '\"');
+    wfp_impl_json_writer_write_raw(writer, key, length);
+    wfp_impl_json_writer_write_raw_char(writer, '\"');
+    wfp_impl_json_writer_write_raw_char(writer, ':');
 }
 
 void
 wfp_impl_json_writer_array_begin(
     struct wfp_json_writer * writer)
 {
+    wfp_impl_json_writer_begin_value(writer);
+    wfp_impl_json_writer_push(writer, WFP_JSON_WRITER_STATE_ARRAY_FIRST);
+
     wfp_impl_json_writer_reserve(writer, 1);
     wfp_impl_json_writer_write_raw_char(writer, '[');
 }
@@ -167,4 +358,7 @@ wfp_impl_json_writer_array_end(
 {
     wfp_impl_json_writer_reserve(writer, 1);
     wfp_impl_json_writer_write_raw_char(writer, ']');
+
+    wfp_impl_json_writer_pop(writer);
+    wfp_impl_json_writer_end_value(writer);
 }

lib/webfuse_provider/impl/json/writer.h

@@ -4,7 +4,7 @@
 #ifndef __cplusplus
 #include <stddef.h>
 #else
-#include <cstddef.h>
+#include <cstddef>
 #endif
 
 #ifdef __cplusplus
@@ -23,9 +23,14 @@ extern void
 wfp_impl_json_writer_dispose(
     struct wfp_json_writer * writer);
 
+extern void
+wfp_impl_json_writer_reset(
+    struct wfp_json_writer * writer);
+
 extern char *
 wfp_impl_json_writer_take_data(
-    struct wfp_json_writer * writer);
+    struct wfp_json_writer * writer,
+    size_t * size);
 
 extern void
 wfp_impl_json_writer_write_int(
@@ -37,6 +42,11 @@ wfp_impl_json_writer_write_string(
     struct wfp_json_writer * writer,
     char const * value);
 
+extern void
+wfp_impl_json_writer_write_string_nocheck(
+    struct wfp_json_writer * writer,
+    char const * value);
+
 extern void
 wfp_impl_json_writer_write_bytes(
     struct wfp_json_writer * writer,