6 files changed, 337 insertions, 0 deletions

diff --git a/lib/lib.c b/lib/lib.c
new file mode 100644
index 0000000..e6e691a
--- /dev/null
+++ b/lib/lib.c
@@ -0,0 +1,51 @@
+#include "lib.h"
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+__attribute__((__noreturn__))
+static void die() {
+	exit(1);
+}
+
+void error_and_die(char *format, ...) {
+	va_list list;
+	va_start(list, format);
+
+	vfprintf(stderr, format, list);
+
+	die();
+}
+
+__attribute__((__noreturn__, format(printf, 1, 2)))
+void perror_and_die(char *format, ...) {
+	va_list list;
+	va_start(list, format);
+
+	vfprintf(stderr, format, list);
+	perror(": ");
+
+	die();
+}
+
+void *xalloc(size_t amount) {
+	void *res = malloc(amount);
+	if (res == NULL)
+		error_and_die("failed to allocate memory");
+	return res;
+}
+
+void *xzalloc(size_t amount) {
+	void *res = xalloc(amount);
+	memset(res, 0, sizeof(amount));
+	return res;
+}
+
+void *xrealloc(void *ptr, size_t amount) {
+	void *res = realloc(ptr, amount);
+	if (res == NULL)
+		error_and_die("failed to allocate memory");
+	return res;
+}
diff --git a/lib/lib.h b/lib/lib.h
new file mode 100644
index 0000000..35cbc3c
--- /dev/null
+++ b/lib/lib.h
@@ -0,0 +1,13 @@
+#pragma once
+
+#include <stddef.h>
+
+__attribute__((__noreturn__, format(printf, 1, 2)))
+void error_and_die(char *format, ...);
+
+__attribute__((__noreturn__, format(printf, 1, 2)))
+void perror_and_die(char *format, ...);
+
+void *xalloc(size_t amount);
+void *xzalloc(size_t amount);
+void *xrealloc(void *ptr, size_t amount);
diff --git a/lib/map.c b/lib/map.c
new file mode 100644
index 0000000..71300fb
--- /dev/null
+++ b/lib/map.c
@@ -0,0 +1,87 @@
+#include "lib.h"
+#include "nbt.h"
+#include "map.h"
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+void map_init(map_t *map) {
+	map->len = 0;
+	map->capacity = 0;
+	map->entries = NULL;
+}
+
+void map_free(map_t *map) {
+	if (map->entries == NULL)
+		return;
+	for (uint32_t i = 0; i < map->capacity; i++) {
+		if (map->entries[i].name != NULL)
+			tag_free(&map->entries[i]);
+	}
+	free(map->entries);
+}
+
+static uint32_t hash(const char *name, uint16_t len) {
+    uint32_t hash = 2166136261u;
+    while(len > 0) {
+        hash ^= (uint8_t)(*name);
+        hash *= 16777619;
+        name++;
+		len--;
+    }
+    return hash;
+}
+
+static tag_t *map_find(tag_t *entries, uint32_t capacity, tag_t *tag) {
+	uint32_t index = hash(tag->name, tag->name_len) % capacity;
+	while(true) {
+		tag_t *entry = &entries[index];
+		if (entry->name == NULL) {
+			return entry;
+		} else if (
+			entry->name_len == tag->name_len && 
+			memcmp(entry->name, tag->name, tag->name_len) == 0
+		) {
+			return entry;
+		}
+		index += 1;
+		index %= capacity;
+	}
+}
+
+static void map_grow(map_t *map, uint32_t capacity) {
+	tag_t *entries = xzalloc(capacity * sizeof(tag_t));
+	for (uint32_t i = 0; i < capacity; i++) {
+		entries[i].name = NULL;
+		entries[i].name_len = 0;
+	}
+	map->len = 0;
+	for (uint32_t i = 0; i < map->capacity; i++) {
+		tag_t *tag = &map->entries[i];
+		if (tag->name == NULL) continue;
+
+		tag_t *dest = map_find(entries, capacity, tag);
+		*dest = *tag;
+		map->len++;
+	}
+	free(map->entries);
+
+	map->entries = entries;
+	map->capacity = capacity;
+}
+
+void map_put(map_t *map, tag_t *tag) {
+	if (map->len + 1 > map->capacity * 0.75) {
+		int capacity = (map->capacity == 0 ? 8 : (2 * map->capacity));
+		map_grow(map, capacity);
+	}
+	tag_t *dest = map_find(map->entries, map->capacity, tag);
+	if (dest->name == NULL) {
+		map->len++;
+	} else {
+		tag_free(dest);
+	}
+	*dest = *tag;
+}
diff --git a/lib/map.h b/lib/map.h
new file mode 100644
index 0000000..d2ab6f8
--- /dev/null
+++ b/lib/map.h
@@ -0,0 +1,15 @@
+#pragma once
+
+#include <stdint.h>
+
+struct tag_t;
+
+typedef struct {
+	uint32_t len;
+	uint32_t capacity;
+	struct tag_t *entries;
+} map_t;
+
+void map_init(map_t *map);
+void map_free(map_t *map);
+void map_put(map_t *map, struct tag_t *tag);
diff --git a/lib/stream.c b/lib/stream.c
new file mode 100644
index 0000000..6780d02
--- /dev/null
+++ b/lib/stream.c
@@ -0,0 +1,144 @@
+#include "stream.h"
+#include "lib.h"
+
+#include <errno.h>
+#include <netinet/in.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static uint64_t longswap(uint64_t ll) {
+	if (htons(20) == 20)
+		return ll;
+
+	union { uint64_t ll; uint8_t c[8]; } out = {0};
+	union { uint64_t ll; uint8_t c[8]; } in = {ll};
+
+	for (int i = 0; i < 8; i++)
+		out.c[7-i] = in.c[i];
+
+	return out.ll;
+}
+
+
+stream_t stream_open(const char *path, const char* mode) {
+	stream_t stream;
+
+	if (strcmp("-", path) == 0) {
+		if (*mode == 'r')
+			stream.__file = stdin;
+		else
+			stream.__file = stdout;
+		stream.__alloc = false;
+		return stream;
+	}
+
+	stream.__file = fopen(path, mode);
+	stream.__alloc = true;
+
+	if (stream.__file == NULL) {
+		perror_and_die("cannot open '%s'", path);
+	};
+
+	return stream;
+}
+
+void stream_close(stream_t *stream) {
+	if (stream->__alloc)
+		fclose(stream->__file);
+}
+
+bool stream_read(const stream_t *stream, void *res, size_t amount) {
+	size_t read;
+	read = fread(res, 1, amount, stream->__file);
+
+	if (read == 0) {
+		if (feof(stream->__file) || errno == 0)
+			return false;
+		else
+		    perror_and_die("cannot read from stream");
+	}
+
+	return true;
+}
+
+bool stream_read_i8(const stream_t *stream, int8_t *res) {
+	if (stream_read(stream, res, 1) == false)
+		return false;
+	return true;
+}
+
+bool stream_read_i16(const stream_t *stream, int16_t *res) {
+	if (stream_read(stream, res, 2) == false)
+		return false;
+	*res = ntohs(*res);
+	return true;
+}
+
+bool stream_read_i32(const stream_t *stream, int32_t *res) {
+	if (stream_read(stream, res, 4) == false)
+		return false;
+	*res = ntohl(*res);
+	return true;
+}
+
+bool stream_read_i64(const stream_t *stream, int64_t *res) {
+	if (stream_read(stream, res, 8) == false)
+		return false;
+	*res = longswap(*res);
+	return true;
+}
+
+bool stream_read_u16(const stream_t *stream, uint16_t *res) {
+	if (stream_read(stream, res, 2) == false)
+		return false;
+	*res = ntohs(*res);
+	return true;
+}
+
+bool stream_write(const stream_t *stream, const void *buf, size_t amount) {
+	size_t wrote;
+	wrote = fwrite(buf, 1, amount, stream->__file);
+
+	if (wrote == 0)
+		perror_and_die("cannot write to stream");
+
+	if (wrote < amount)
+		return false;
+
+	return true;
+}
+
+bool stream_write_i8(const stream_t *stream, int8_t b) {
+	if (stream_write(stream, &b, 1) == false)
+		return false;
+	return true;
+}
+
+bool stream_write_i16(const stream_t *stream, int16_t s) {
+	s = htons(s);
+	if (stream_write(stream, &s, 2) == false)
+		return false;
+	return true;
+}
+
+bool stream_write_i32(const stream_t *stream, int32_t i) {
+	i = htonl(i);
+	if (stream_write(stream, &i, 4) == false)
+		return false;
+	return true;
+}
+
+bool stream_write_i64(const stream_t *stream, int64_t l) {
+	l = longswap(l);
+	if (stream_write(stream, &l, 8) == false)
+		return false;
+	return true;
+}
+
+bool stream_write_u16(const stream_t *stream, uint16_t s) {
+	s = htons(s);
+	if (stream_write(stream, &s, 2) == false)
+		return false;
+	return true;
+}
diff --git a/lib/stream.h b/lib/stream.h
new file mode 100644
index 0000000..d9a05ce
--- /dev/null
+++ b/lib/stream.h
@@ -0,0 +1,27 @@
+#pragma once
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdbool.h>
+
+typedef struct {
+	FILE *__file;
+	bool __alloc;
+} stream_t;
+
+stream_t stream_open(const char *path, const char* mode);
+void stream_close(stream_t *stream);
+
+bool stream_read(const stream_t *stream, void *res, size_t amount);
+bool stream_read_i8(const stream_t *stream, int8_t *res);
+bool stream_read_i16(const stream_t *stream, int16_t *res);
+bool stream_read_i32(const stream_t *stream, int32_t *res);
+bool stream_read_i64(const stream_t *stream, int64_t *res);
+bool stream_read_u16(const stream_t *stream, uint16_t *res);
+
+bool stream_write(const stream_t *stream, const void *buf, size_t amount);
+bool stream_write_i8(const stream_t *stream, int8_t b);
+bool stream_write_i16(const stream_t *stream, int16_t s);
+bool stream_write_i32(const stream_t *stream, int32_t i);
+bool stream_write_i64(const stream_t *stream, int64_t l);
+bool stream_write_u16(const stream_t *stream, uint16_t s);