From 3e9abd62c9e412c72cbf42d1ff4b7ff33f57161e Mon Sep 17 00:00:00 2001
From: Lucas Schwiderski <lucas@lschwiderski.de>
Date: Fri, 21 Oct 2022 23:50:22 +0200
Subject: [PATCH] feat: Remove brute-forcing the uncompressed size

We figured out Fatshark's chunk sizes, so this is now unneeded
complexity.
---
 oodle-cli.cpp | 115 +++++++++++++++-----------------------------------
 1 file changed, 35 insertions(+), 80 deletions(-)

diff --git a/oodle-cli.cpp b/oodle-cli.cpp
index 5dc4b09..7b446ca 100644
--- a/oodle-cli.cpp
+++ b/oodle-cli.cpp
@@ -25,26 +25,22 @@ const char* LIB_FILE = "oo2core_8_win64.dll";
 typedef decltype(OodleLZ_Decompress)* decompress_func;
 typedef decltype(OodleCore_Plugins_SetPrintf)* setprintf_func;
 
-#define OK 0
-#define GENERIC_ERROR -1
-#define DECOMPRESS_ERROR -2
 
 void usage() {
     std::cerr <<
         "Usage: oodle-cli [OPTIONS] [--] <in_file> <out_file> <uncompressed_size>\n"
         "Decompress a <in_file> to <out_file> using the Oodle algorithm.\n"
-        "The size of the uncompressed data must be known. If 0 is given, the tool will\n"
-        "attempt to brute-force the correct number by incrementing from the compressed size.\n"
+        "The size of the uncompressed data must be known.\n"
         "\n"
         "Options:\n"
         "  -v  Increase Oodle's verbosity. May be specified up to three times.\n"
         "  -c  Only check if the library can be found and used.\n"
-        "  --guess <number> When guessing the uncompressed size, a maximum number as multiple of the compressed size prevents an infinite loop. This changes the factor. Defaults to 10."
         "\n"
         "The following environmental variables are recognized:\n"
         "  DLL_SEARCH_PATH: A color (':') separated list of directories to search for the Oodle library. May be relative to the current working directory.\n";
 }
 
+
 void printf_callback(int verboseLevel, const char* file, int line, const char* fmt, ...) {
     std::cout << "[OODLE] ";
 
@@ -66,51 +62,11 @@ void printf_callback(int verboseLevel, const char* file, int line, const char* f
     vfprintf(stdout, fmt, args);
 }
 
-int do_decompress(decompress_func decompress, std::vector<char> compressed_buffer, std::string out_name, size_t raw_buffer_size, OodleLZ_Verbosity verbosity) {
-    std::vector<char> raw_buffer(raw_buffer_size);
-
-    intptr_t res = decompress(
-        compressed_buffer.data(),
-        compressed_buffer.size(),
-        raw_buffer.data(),
-        raw_buffer_size,
-        OodleLZ_FuzzSafe_Yes,
-        OodleLZ_CheckCRC_No,
-        verbosity,
-        nullptr,
-        0,
-        nullptr,
-        nullptr,
-        nullptr,
-        0,
-        OodleLZ_Decode_Unthreaded
-    );
-
-    if (res != raw_buffer_size) {
-        return DECOMPRESS_ERROR;
-    }
-
-    std::ofstream out_file(out_name, std::ios::binary);
-    if (!out_file) {
-        std::cerr << "ERROR: Failed to open output file!\n";
-        return GENERIC_ERROR;
-    }
-
-    out_file.write(raw_buffer.data(), res);
-
-    if (out_file.fail()) {
-        std::cerr << "ERROR: Failed to write output file!\n";
-        return GENERIC_ERROR;
-    }
-
-    return OK;
-}
 
 int main(int argc, char* argv[])
 {
     int verbosity = 0;
     bool check_lib = FALSE;
-    int guess_factor = 10;
     int i = 1;
 
     for (; i < argc; i++) {
@@ -130,12 +86,10 @@ int main(int argc, char* argv[])
         else if (strcmp(arg, "-v") == 0) {
             verbosity++;
         }
-        else if (strcmp(arg, "--guess") == 0) {
-            i++;
-            guess_factor = std::stoi(argv[i]);
-        }
         else {
-            std::cerr << "WARN: Unknown option '" << arg << "'!\n\n";
+            std::cerr << "ERROR: Unknown option '" << arg << "'!\n\n";
+            usage();
+            return 1;
         }
     }
 
@@ -225,40 +179,41 @@ int main(int argc, char* argv[])
         return 1;
     }
 
-    if (raw_buffer_size > 0) {
-        int res = do_decompress(decompress, compressed_buffer, out_name, raw_buffer_size, (OodleLZ_Verbosity)verbosity);
+    std::vector<char> raw_buffer(raw_buffer_size);
 
-        if (res == DECOMPRESS_ERROR) {
-            std::cerr << "ERROR: Failed to decompress!\n";
-            return 1;
-        }
-        else if (res == GENERIC_ERROR) {
-            return 1;
-        }
+    intptr_t res = decompress(
+        compressed_buffer.data(),
+        compressed_buffer.size(),
+        raw_buffer.data(),
+        raw_buffer_size,
+        OodleLZ_FuzzSafe_Yes,
+        OodleLZ_CheckCRC_No,
+        (OodleLZ_Verbosity)verbosity,
+        nullptr,
+        0,
+        nullptr,
+        nullptr,
+        nullptr,
+        0,
+        OodleLZ_Decode_Unthreaded
+    );
+
+    if (res != raw_buffer_size) {
+        std::cerr << "ERROR: Failed to decompress!\n";
+        return 1;
     }
-    else {
-        size_t guessed_size = compressed_buffer.size();
-        // I need some maximum value to avoid infinite loops. The factor is configurable.
-        size_t max = guessed_size * guess_factor;
 
-        while (true) {
-            int res = do_decompress(decompress, compressed_buffer, out_name, guessed_size, (OodleLZ_Verbosity)verbosity);
-            
-            if (res == GENERIC_ERROR) {
-                return 1;
-            }
-            else if (res == OK) {
-                std::cout << "INFO: Found decompressed size as " << guessed_size << "\n";
-                break;
-            }
+    std::ofstream out_file(out_name, std::ios::binary);
+    if (!out_file) {
+        std::cerr << "ERROR: Failed to open output file!\n";
+        return 1;
+    }
 
-            guessed_size++;
+    out_file.write(raw_buffer.data(), res);
 
-            if (guessed_size > max) {
-                std::cerr << "ERROR: Exceeded maximum value for guessing uncompressed size!\n";
-                return 1;
-            }
-        }
+    if (out_file.fail()) {
+        std::cerr << "ERROR: Failed to write output file!\n";
+        return 1;
     }
 
     std::cout << "INFO: Done!\n";