Unconsistent command-line parsing in case of UTF-8 quoted arguments

Brian Inglis Brian.Inglis@SystematicSw.ab.ca
Tue Oct 13 17:34:30 GMT 2020


On 2020-10-06 15:36, Jérôme Froissart wrote:
> Here are the more detailed steps to reproduce the issue (along with
> answers to your requests about `uname`, `locale`, etc.).
> (I mostly reproduced what billziss-gh had done before, I do not take
> all the credits :D)
> 
> Here is an example C file
>     $ cat example.c
>     #include <stdio.h>
> 
>     const char *GetCommandLineA(void);
> 
>     int main(int argc, char *argv[])
>     {
>         const char *s = GetCommandLineA();
>         printf("C=%s\n", s);
> 
>         for (int i = 0; argc > i; i++)
>             printf("%d=%s\n", i, argv[i]);
> 
>         return 0;
>     }
> 
> I have built it with gcc from Cygwin
>     $ gcc -o binary example.c
> 
> Running it from the same Cygwin bash prompt works as expected
>     $ uname -a
>     CYGWIN_NT-10.0 XPS 3.1.5(0.340/5/3) 2020-06-01 08:59 x86_64 Cygwin
>     # (XPS is my Windows machine name)
> 
>     $ locale
>     LANG=fr_FR.UTF-8
>     LC_CTYPE="fr_FR.UTF-8"
>     LC_NUMERIC="fr_FR.UTF-8"
>     LC_TIME="fr_FR.UTF-8"
>     LC_COLLATE="fr_FR.UTF-8"
>     LC_MONETARY="fr_FR.UTF-8"
>     LC_MESSAGES="fr_FR.UTF-8"
>     LC_ALL=
> 
>     $ which gcc
>     /usr/bin/gcc
> 
>     # The following runs as expected
>     $ ./binary.exe "foo bar" "Jérôme"
>     C="C:\Users\Public\binary.exe"
>     0=./binary
>     1=foo bar
>     2=Jérôme
> 
> Now, let's start a Windows shell (cmd.exe)
> Note that I had to copy cygwin1.dll from my Cygwin installation
> directory, otherwise binary.exe would not start.
> I do not know whether there is a `locale` equivalent in Windows
> command prompt, so I merely ran my program.
>     C:\Users\Public>binary.exe "foo bar" "Jérôme"
>     C=binary.exe  "foo bar" "J□r□me"
>     0=binary
>     1=foo bar
>     2="Jérôme"
> 
> This behaviour is not expected and is quite inconsistent with what
> happened through Bash.
> Besides the "strange squares" that appear on the first line, and the
> extra space after binary.exe, I especially did not expect "Jérôme" to
> remain quoted as a second argument.

Don't call inappropriate Windows functions without understanding the limitations
of Windows and its APIs.
Cygwin args are consistent with what you ran and what we would all expect.
I don't see any Cygwin problems here.

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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