[llvm] 0f4c6b1 - [lvm-windres] Try to match GNU windres regarding handling of unescaped quotes

[Martin Storsjö via llvm-commits]

Author: Martin Storsjö
Date: 2023-03-28T11:02:44+03:00
New Revision: 0f4c6b120f21d582ab7c5c4f2b2a475086c34938

URL: https://github.com/llvm/llvm-project/commit/0f4c6b120f21d582ab7c5c4f2b2a475086c34938
DIFF: https://github.com/llvm/llvm-project/commit/0f4c6b120f21d582ab7c5c4f2b2a475086c34938.diff

LOG: [lvm-windres] Try to match GNU windres regarding handling of unescaped quotes

Some background context: GNU windres invokes the preprocessor in
a subprocess. Some windres options are passed through to the
preproocessor, e.g. -D options for predefining defines.
When GNU windres passes these options onwards, it takes the options
in exact the form they are received (in argv or similar) and
assembles them into a single preprocessor command string which gets
interpreted by a shell (IIRC via the popen() function, or similar).

When LLVM invokes subprocesses, it does so via APIs that take
properly split argument vectors, to avoid needing to worry about
shell quoting/escaping/unescaping. But in the case of LLVM windres,
we have to emulate the effect of the shell parsing done by popen().

Most of the relevant cases are already taken care of here, but this
patch fixes an uncommon case encountered in
https://github.com/llvm/llvm-project/issues/57334.
(This case is uncommon since it doesn't do what one would want to;
the quotes need to be escaped more to work as intended through
the popen() shell).

Differential Revision: https://reviews.llvm.org/D146848

Added: 
    

Modified: 
    llvm/test/tools/llvm-rc/windres-preproc.test
    llvm/tools/llvm-rc/llvm-rc.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/test/tools/llvm-rc/windres-preproc.test b/llvm/test/tools/llvm-rc/windres-preproc.test
index 88ca08988c015..e7f83074c0406 100644
--- a/llvm/test/tools/llvm-rc/windres-preproc.test
+++ b/llvm/test/tools/llvm-rc/windres-preproc.test
@@ -1,4 +1,4 @@
-; RUN: llvm-windres -### --include-dir %p/incdir1 --include %p/incdir2 "-DFOO1=\\\"foo bar\\\"" -UFOO2 -D FOO3 --preprocessor-arg "-DFOO4=\\\"baz baz\\\"" %p/Inputs/empty.rc %t.res | FileCheck %s --check-prefix=CHECK1
-; CHECK1: {{^}} "clang" "--driver-mode=gcc" "-target" "{{.*}}-{{.*}}{{mingw32|windows-gnu}}" "-E" "-xc" "-DRC_INVOKED" "{{.*}}empty.rc" "-o" "{{.*}}preproc-{{.*}}.rc" "-I" "{{.*}}incdir1" "-I" "{{.*}}incdir2" "-D" "FOO1=\"foo bar\"" "-U" "FOO2" "-D" "FOO3" "-DFOO4=\"baz baz\""{{$}}
+; RUN: llvm-windres -### --include-dir %p/incdir1 --include %p/incdir2 "-DFOO1=\\\"foo bar\\\"" -UFOO2 -D FOO3 --preprocessor-arg "-DFOO4=\\\"baz baz\\\"" -DFOO5=\"bar\" %p/Inputs/empty.rc %t.res | FileCheck %s --check-prefix=CHECK1
+; CHECK1: {{^}} "clang" "--driver-mode=gcc" "-target" "{{.*}}-{{.*}}{{mingw32|windows-gnu}}" "-E" "-xc" "-DRC_INVOKED" "{{.*}}empty.rc" "-o" "{{.*}}preproc-{{.*}}.rc" "-I" "{{.*}}incdir1" "-I" "{{.*}}incdir2" "-D" "FOO1=\"foo bar\"" "-U" "FOO2" "-D" "FOO3" "-DFOO4=\"baz baz\"" "-D" "FOO5=bar"{{$}}
 ; RUN: llvm-windres -### --preprocessor "i686-w64-mingw32-gcc -E -DFOO=\\\"foo\\ bar\\\"" %p/Inputs/empty.rc %t.res | FileCheck %s --check-prefix=CHECK2
 ; CHECK2: {{^}} "i686-w64-mingw32-gcc" "-E" "-DFOO=\"foo bar\"" "{{.*}}empty.rc" "-o" "{{.*}}preproc-{{.*}}.rc"{{$}}

diff  --git a/llvm/tools/llvm-rc/llvm-rc.cpp b/llvm/tools/llvm-rc/llvm-rc.cpp
index d77d68fa09868..d964321401a46 100644
--- a/llvm/tools/llvm-rc/llvm-rc.cpp
+++ b/llvm/tools/llvm-rc/llvm-rc.cpp
@@ -322,6 +322,9 @@ std::string unescape(StringRef S) {
       else
         fatalError("Unterminated escape");
       continue;
+    } else if (S[I] == '"') {
+      // This eats an individual unescaped quote, like a shell would do.
+      continue;
     }
     Out.push_back(S[I]);
   }