add json support and other things

1 files changed, 210 insertions, 0 deletions

diff --git a/src/nbt/read.c b/src/nbt/read.c
new file mode 100644
index 0000000..d5dd827
--- /dev/null
+++ b/src/nbt/read.c
@@ -0,0 +1,210 @@
+#include "nbt.h"
+#include "../lib.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static bool nbt_read_data(tag_t *tag, const stream_t *stream);
+
+static bool nbt_read_header(tag_t *tag, const stream_t *stream, bool named) {
+	bool ok = true;
+
+	if (stream_read_i8(stream, &tag->type) == false)
+		return false;
+
+	if (tag->type == TAG_END)
+		named = false;
+
+	if (named) {
+		if (stream_read_u16(stream, &tag->name_len) == false)
+			return false;
+	} else {
+		tag->name_len = 0;
+	}
+
+	if (tag->name_len < 1) {
+		tag->name = "";
+	} else {
+		tag->name = xalloc(tag->name_len);
+		ok = stream_read(stream, tag->name, tag->name_len);
+	}
+
+	if (!ok)
+		return false;
+
+	return true;
+}
+
+
+static bool nbt_read_byte_array(tagdata_t *data, const stream_t *stream) {
+	if (stream_read_i32(stream, &data->b_arr.size) == false)
+		return false;
+	if (data->b_arr.size == 0) {
+		data->b_arr.data = NULL;
+		return true;
+	}
+	data->b_arr.data = xalloc(data->b_arr.size * sizeof(int8_t));
+	for (int32_t i = 0; i < data->b_arr.size; i++)
+		if (stream_read_i8(stream, &data->b_arr.data[i]) == false)
+			return false;
+	return true;
+}
+
+static bool nbt_read_int_array(tagdata_t *data, const stream_t *stream) {
+	if (stream_read_i32(stream, &data->i_arr.size) == false)
+		return false;
+	if (data->i_arr.size == 0) {
+		data->i_arr.data = NULL;
+		return true;
+	}
+	data->i_arr.data = xalloc(data->i_arr.size * sizeof(int32_t));
+	for (int32_t i = 0; i < data->i_arr.size; i++)
+		if (stream_read_i32(stream, &data->i_arr.data[i]) == false)
+			return false;
+	return true;
+}
+
+static bool nbt_read_long_array(tagdata_t *data, const stream_t *stream) {
+	if (stream_read_i32(stream, &data->l_arr.size) == false)
+		return false;
+	if (data->l_arr.size == 0) {
+		data->l_arr.data = NULL;
+		return true;
+	}
+	data->l_arr.data = xalloc(data->l_arr.size * sizeof(int64_t));
+	for (int32_t i = 0; i < data->l_arr.size; i++)
+		if (stream_read_i64(stream, &data->l_arr.data[i]) == false)
+			return false;
+	return true;
+}
+
+static bool nbt_read_string(tagdata_t *data, const stream_t *stream) {
+	if (stream_read_u16(stream, &data->string.size) == false)
+		return false;
+	if (data->string.size < 1) {
+		data->string.data = NULL;
+		return true;
+	}
+	data->string.data = xalloc(data->string.size);
+	if (stream_read(stream, data->string.data, data->string.size) == false)
+		return false;
+	return true;
+}
+
+static bool nbt_read_list(tagdata_t *data, const stream_t *stream) {
+	if (stream_read_i8(stream, &data->list.type) == false)
+		return false;
+	if (stream_read_i32(stream, &data->list.size) == false)
+		return false;
+	if (data->list.size <= 0) {
+		data->list.tags = NULL;
+		return true;
+	} else if (data->list.type == 0) {
+		// tag end is not allowed to be used with non empty list
+		return false;
+	}
+	data->list.tags = xalloc(data->list.size * sizeof(tag_t));
+	for (int32_t i = 0; i < data->list.size; i++) {
+		tag_t tag;
+		tag.type = data->list.type;
+		tag.name = "";
+		tag.name_len = 0;
+		if (nbt_read_data(&tag, stream) == false)
+			return false;
+		data->list.tags[i] = tag;
+	}
+	return true;
+}
+
+static bool nbt_read_compound(tagdata_t *data, const stream_t *stream) {
+	int32_t size = 0;
+	int32_t capacity = 8;
+	tag_t *tags = xalloc(capacity * sizeof(tag_t));
+
+	while (1) {
+
+		tag_t tag;
+
+		if (nbt_read_header(&tag, stream, true) == false) {
+			free(tags);
+			return false;
+		}
+
+		if (tag.type == TAG_END)
+			break;
+
+		if (nbt_read_data(&tag, stream) == false) {
+			free(tags);
+			return false;
+		}
+		
+		if (size == capacity) {
+			capacity *= 2;
+			tags = xrealloc(tags, capacity * sizeof(tag_t));
+		}
+
+		tags[size++] = tag;
+	}
+
+	data->compound.size = size;
+	data->compound.tags = xalloc(size * sizeof(tag_t));
+	memcpy(data->compound.tags, tags, size * sizeof(tag_t));
+	free(tags);
+
+	return true;
+}
+
+static bool nbt_read_data(tag_t *tag, const stream_t *stream) {
+	bool ok = true;
+
+	switch (tag->type) {
+        case TAG_END:
+			// tag has no data
+			break;
+        case TAG_BYTE:
+			ok = stream_read_i8(stream, &tag->data.b);
+			break;
+        case TAG_SHORT:
+			ok = stream_read_i16(stream, &tag->data.s);
+			break;
+        case TAG_FLOAT:
+        case TAG_INT:
+			ok = stream_read_i32(stream, &tag->data.i);
+			break;
+        case TAG_DOUBLE:
+        case TAG_LONG:
+			ok = stream_read_i64(stream, &tag->data.l);
+			break;
+        case TAG_BYTE_ARRAY:
+			ok = nbt_read_byte_array(&tag->data, stream);
+			break;
+        case TAG_STRING:
+			ok = nbt_read_string(&tag->data, stream);
+			break;
+        case TAG_LIST:
+			ok = nbt_read_list(&tag->data, stream);
+			break;
+        case TAG_COMPOUND:
+			ok = nbt_read_compound(&tag->data, stream);
+			break;
+        case TAG_INT_ARRAY:
+			ok = nbt_read_int_array(&tag->data, stream);
+			break;
+        case TAG_LONG_ARRAY:
+			ok = nbt_read_long_array(&tag->data, stream);
+			break;
+          break;
+        };
+    return ok;
+}
+
+bool nbt_read(tag_t *tag, const stream_t *stream) {
+	memset(tag, 0, sizeof(tag_t));
+	if (nbt_read_header(tag, stream, true) == false)
+		return false;
+	if (nbt_read_data(tag, stream) == false)
+		return false;
+	return true;
+}
+