From 0b2eca3066975dadb594195542b0c3e20ae48762 Mon Sep 17 00:00:00 2001
From: paxcut <53811119+paxcut@users.noreply.github.com>
Date: Sun, 15 Sep 2024 06:20:17 -0700
Subject: [PATCH] fix: LZMA decompressor memory errors (#1873)

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### Problem description
I was unable to use the LZMA de-compressor even though 7zip was able to
identify them as LZMA compressed and decompress them without a problem.
Under the debugger the `lzma_code()` call was returning
`LZMA_MEMLIMIT_ERROR`.
### Implementation description
I found online that the error can be fixed using `lzma_memlimit_set()`
using a value obtained with `lzma_memusage()`. I tried to avoid having
to call `lzma_code()` twice but if the functions are called before the
first `lzma_code()`the values of memory obtained fall short and error
occurs again.

I suspect that there are better ways to deal with this other than the
code proposed in this PR, but I haven't been able to find any.

---------

Co-authored-by: Nik <werwolv98@gmail.com>
---
 plugins/decompress/source/content/pl_functions.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/plugins/decompress/source/content/pl_functions.cpp b/plugins/decompress/source/content/pl_functions.cpp
index 5589a1b95..87388be39 100644
--- a/plugins/decompress/source/content/pl_functions.cpp
+++ b/plugins/decompress/source/content/pl_functions.cpp
@@ -174,6 +174,13 @@ namespace hex::plugin::decompress {
                         section.resize(section.size() - stream.avail_out);
                         break;
                     }
+
+                    if (res == LZMA_MEMLIMIT_ERROR) {
+                        auto usage = lzma_memusage(&stream);
+                        lzma_memlimit_set(&stream, usage);
+                        res = lzma_code(&stream, LZMA_RUN);
+                    }
+
                     if (res != LZMA_OK)
                         return false;