frontend: Migrate Windows updater

2026-09-24 23:31:36 +08:00 · 2025-01-08 17:33:13 +01:00
parent 2be464a21f
commit ff3b62422e
13 changed files with 1 additions and 1 deletions
@@ -0,0 +1,140 @@
+/*
+ * Copyright (c) 2023 Lain Bailey <lain@obsproject.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "updater.hpp"
+
+#include <vector>
+
+using namespace std;
+
+/* ------------------------------------------------------------------------ */
+
+static int64_t offtin(const uint8_t *buf)
+{
+	int64_t y;
+
+	y = buf[7] & 0x7F;
+	y = y * 256;
+	y += buf[6];
+	y = y * 256;
+	y += buf[5];
+	y = y * 256;
+	y += buf[4];
+	y = y * 256;
+	y += buf[3];
+	y = y * 256;
+	y += buf[2];
+	y = y * 256;
+	y += buf[1];
+	y = y * 256;
+	y += buf[0];
+
+	if (buf[7] & 0x80)
+		y = -y;
+
+	return y;
+}
+
+/* ------------------------------------------------------------------------ */
+
+constexpr const char *kDeltaMagic = "BOUF//ZSTD//DICT";
+constexpr int kMagicSize = 16;
+constexpr int kHeaderSize = kMagicSize + 8; // magic + int64_t delta size
+
+int ApplyPatch(ZSTD_DCtx *zstdCtx, const std::byte *patch_data, const size_t patch_size, const wchar_t *targetFile)
+try {
+	int64_t newsize;
+	bool success;
+
+	WinHandle hTarget;
+
+	/* --------------------------------- *
+	 * open patch and file to patch      */
+
+	hTarget = CreateFile(targetFile, GENERIC_READ, 0, nullptr, OPEN_EXISTING, 0, nullptr);
+	if (!hTarget.Valid())
+		throw int(GetLastError());
+
+	/* --------------------------------- *
+	 * read patch header                 */
+
+	if (memcmp(patch_data, kDeltaMagic, kMagicSize) != 0)
+		throw int(-4);
+
+	/* --------------------------------- *
+	 * allocate new file size data       */
+
+	newsize = offtin((const uint8_t *)patch_data + kMagicSize);
+	if (newsize < 0 || newsize >= 0x7ffffffff)
+		throw int(-5);
+
+	vector<std::byte> newData;
+	try {
+		newData.resize((size_t)newsize);
+	} catch (...) {
+		throw int(-1);
+	}
+
+	/* --------------------------------- *
+	 * read old file                     */
+
+	DWORD read;
+	DWORD oldFileSize;
+
+	oldFileSize = GetFileSize(hTarget, nullptr);
+	if (oldFileSize == INVALID_FILE_SIZE)
+		throw int(GetLastError());
+
+	vector<std::byte> oldData;
+	try {
+		oldData.resize(oldFileSize);
+	} catch (...) {
+		throw int(-1);
+	}
+
+	if (!ReadFile(hTarget, oldData.data(), oldFileSize, &read, nullptr))
+		throw int(GetLastError());
+	if (read != oldFileSize)
+		throw int(-1);
+
+	/* --------------------------------- *
+	 * patch to new file data            */
+
+	size_t result = ZSTD_decompress_usingDict(zstdCtx, newData.data(), newData.size(), patch_data + kHeaderSize,
+						  patch_size - kHeaderSize, oldData.data(), oldData.size());
+
+	if (result != newsize || ZSTD_isError(result))
+		throw int(-9);
+
+	/* --------------------------------- *
+	 * write new file                    */
+
+	hTarget = nullptr;
+	hTarget = CreateFile(targetFile, GENERIC_WRITE, 0, nullptr, CREATE_ALWAYS, 0, nullptr);
+	if (!hTarget.Valid())
+		throw int(GetLastError());
+
+	DWORD written;
+
+	success = !!WriteFile(hTarget, newData.data(), (DWORD)newsize, &written, nullptr);
+	if (!success || written != newsize)
+		throw int(GetLastError());
+
+	return 0;
+
+} catch (int code) {
+	return code;
+}