Re: [RFA] Environment variables passed to inferior by MinGW build (PR 10989)

[Eli Zaretskii <eliz at gnu dot org>]

Ping!  Ping!  (2 weeks)

> Date: Mon, 19 Sep 2011 03:37:06 -0400
> From: Eli Zaretskii <eliz@gnu.org>
> Reply-to: Eli Zaretskii <eliz@gnu.org>
> 
> Ping!
> 
> > Date: Sun, 11 Sep 2011 08:33:25 -0400
> > From: Eli Zaretskii <eliz@gnu.org>
> > CC: Corinna Vinschen <vinschen@redhat.com>
> > 
> > There's some history to this issue.  It was discussed at least twice
> > before:
> > 
> >    http://sourceware.org/ml/gdb-patches/2010-05/msg00317.html
> >    http://sourceware.org/ml/gdb-patches/2011-04/msg00347.html
> > 
> > The first discussion simply died because the OP never responded to
> > Joel's request to clean up the patch from weird characters.
> > 
> > As for the second discussion, upon re-reading it I can only assume
> > that there was a misunderstanding of some kind, perhaps Pierre was
> > talking about both the Cygwin and the native Windows builds, while
> > Chris and Corinna replied only about the latter.
> > 
> > In any case, the original problem is still there in the MinGW build of
> > GDB 7.3, and it just bit me hard enough to sit down and solve it.
> > 
> > The code in the patch below is simply taken from what was there before
> > it was deleted by Corinna back in 2006, after removing from it
> > everything that was Cygwin-specific.  So I don't even think I can take
> > credit for this code ;-)
> > 
> > With that patch, I can add environment variables with "set
> > environment", delete them with "unset environment", and the inferior
> > gets the environment I meant it to have.
> > 
> > OK to commit?
> > 
> > 2011-09-11  Eli Zaretskii  <eliz@gnu.org>
> > 
> > 	* windows-nat.c (env_sort) [!__CYGWIN__]: Function restored from
> > 	before the change on 2006-12-09.
> > 	(windows_create_inferior) [!__CYGWIN__]: Restore code that
> > 	generates the environment block for CreateProcessA, modulo the
> > 	Cygwin-specific parts that are not needed here.
> > 
> > 
> > === modified file 'gdb/windows-nat.c'
> > --- gdb/windows-nat.c	2011-05-09 14:25:35 +0000
> > +++ gdb/windows-nat.c	2011-09-11 12:26:41 +0000
> > @@ -1951,6 +1951,17 @@
> >    *flags |= CREATE_NEW_CONSOLE;
> >  }
> >  
> > +#ifndef __CYGWIN__
> > +/* Function called by qsort to sort environment strings.  */
> > +static int
> > +env_sort (const void *a, const void *b)
> > +{
> > +  const char **p = (const char **) a;
> > +  const char **q = (const char **) b;
> > +  return strcasecmp (*p, *q);
> > +}
> > +#endif
> > +
> >  /* Start an inferior windows child process and sets inferior_ptid to its pid.
> >     EXEC_FILE is the file to run.
> >     ALLARGS is a string containing the arguments to the program.
> > @@ -1977,6 +1988,12 @@
> >    char *toexec;
> >    char *args;
> >    HANDLE tty;
> > +  char *w32env;
> > +  char *temp;
> > +  size_t envlen;
> > +  int i;
> > +  size_t envsize;
> > +  char **env;
> >  #endif
> >    PROCESS_INFORMATION pi;
> >    BOOL ret;
> > @@ -2124,6 +2141,31 @@
> >  	}
> >      }
> >  
> > +  /* CreateProcess takes the environment list as a null terminated set of
> > +     strings (i.e. two nulls terminate the list).  */
> > +
> > +  /* Get total size for env strings.  */
> > +  for (envlen = 0, i = 0; in_env[i] && *in_env[i]; i++)
> > +    envlen += strlen (in_env[i]) + 1;
> > +
> > +  envsize = sizeof (in_env[0]) * (i + 1);
> > +  env = (char **) alloca (envsize);
> > +  memcpy (env, in_env, envsize);
> > +  /* Windows programs expect the environment block to be sorted.  */
> > +  qsort (env, i, sizeof (char *), env_sort);
> > +
> > +  w32env = alloca (envlen + 1);
> > +
> > +  /* Copy env strings into new buffer.  */
> > +  for (temp = w32env, i = 0; env[i] && *env[i]; i++)
> > +    {
> > +      strcpy (temp, env[i]);
> > +      temp += strlen (temp) + 1;
> > +    }
> > +
> > +  /* Final nil string to terminate new env.  */
> > +  *temp = 0;
> > +
> >    windows_init_thread_list ();
> >    ret = CreateProcessA (0,
> >  			args,	/* command line */
> > @@ -2131,7 +2173,7 @@
> >  			NULL,	/* thread */
> >  			TRUE,	/* inherit handles */
> >  			flags,	/* start flags */
> > -			NULL,	/* environment */
> > +			w32env,	/* environment */
> >  			NULL,	/* current directory */
> >  			&si,
> >  			&pi);
> > 
>