From 2e9d484382fe45ff1dcd325be0992b1857f9498d Mon Sep 17 00:00:00 2001
From: Christopher Faylor <me@cgf.cx>
Date: Thu, 13 Apr 2006 01:37:00 +0000
Subject: [PATCH] * spawn.cc (spawn_guts): Revert patch which treated derived
 cygwin programs differently from those which are mounted with -X.  Pass extra
 argument to linebuf::fromargv. * winf.h (MAXCYGWINCMDLEN): New define.
 (linebuf::finish): Add a new argument denoting when command line overflow is
 ok. (linebuf::fromargv): Ditto. * winf.cc (linebuf::finish): Implement above
 change. (linebuf::fromargv): Ditto.

---
 winsup/cygwin/ChangeLog | 13 +++++++++++++
 winsup/cygwin/spawn.cc  |  7 ++++---
 winsup/cygwin/winf.cc   | 12 ++++++++----
 winsup/cygwin/winf.h    | 12 ++++++++++--
 4 files changed, 35 insertions(+), 9 deletions(-)

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 0352479fb..5e4f22c79 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,16 @@
+2006-04-12  Corinna Vinschen  <corinna@vinschen.de>
+	    Christopher Faylor  <cgf@timesys.com>
+
+	* spawn.cc (spawn_guts): Revert patch which treated derived cygwin
+	programs differently from those which are mounted with -X.  Pass extra
+	argument to linebuf::fromargv.
+	* winf.h (MAXCYGWINCMDLEN): New define.
+	(linebuf::finish): Add a new argument denoting when command line
+	overflow is ok.
+	(linebuf::fromargv): Ditto.
+	* winf.cc (linebuf::finish): Implement above change.
+	(linebuf::fromargv): Ditto.
+
 2006-04-11  Christopher Faylor  <cgf@timesys.com>
 
 	* Makefile.in (DLL_OFILES): Add winf.o.
diff --git a/winsup/cygwin/spawn.cc b/winsup/cygwin/spawn.cc
index 9d358da0c..a39145ed8 100644
--- a/winsup/cygwin/spawn.cc
+++ b/winsup/cygwin/spawn.cc
@@ -347,6 +347,7 @@ spawn_guts (const char * prog_arg, const char *const *argv,
       goto out;
     }
 
+  bool wascygexec = real_path.iscygexec ();
   res = newargv.fixup (prog_arg, real_path, ext);
 
   if (res)
@@ -371,9 +372,9 @@ spawn_guts (const char * prog_arg, const char *const *argv,
     }
   else
     {
-      if (real_path.iscygexec ())
+      if (wascygexec)
 	newargv.dup_all ();
-      else if (!one_line.fromargv (newargv, real_path))
+      else if (!one_line.fromargv (newargv, real_path, real_path.iscygexec ()))
 	{
 	  res = -1;
 	  goto out;
@@ -461,6 +462,7 @@ spawn_guts (const char * prog_arg, const char *const *argv,
 
   cygheap->fdtab.set_file_pointers_for_exec ();
 
+  ch.set (chtype, real_path.iscygexec ());
   moreinfo->envp = build_env (envp, envblock, moreinfo->envc, real_path.iscygexec ());
   if (!moreinfo->envp || !envblock)
     {
@@ -468,7 +470,6 @@ spawn_guts (const char * prog_arg, const char *const *argv,
       res = -1;
       goto out;
     }
-  ch.set (chtype, real_path.iscygexec ());
   ch.moreinfo = moreinfo;
 
   si.lpReserved2 = (LPBYTE) &ch;
diff --git a/winsup/cygwin/winf.cc b/winsup/cygwin/winf.cc
index 01c5cfb65..81c58db4f 100644
--- a/winsup/cygwin/winf.cc
+++ b/winsup/cygwin/winf.cc
@@ -19,12 +19,16 @@ details. */
 #include "sys/cygwin.h"
 
 void
-linebuf::finish ()
+linebuf::finish (bool cmdlenoverflow_ok)
 {
   if (!ix)
     add ("", 1);
   else
-    buf[--ix] = '\0';
+    {
+      if (ix-- > MAXCYGWINCMDLEN && cmdlenoverflow_ok)
+	ix = MAXCYGWINCMDLEN - 1;
+      buf[ix] = '\0';
+    }
 }
 
 void
@@ -61,7 +65,7 @@ linebuf::prepend (const char *what, int len)
 }
 
 bool
-linebuf::fromargv (av& newargv, char *real_path)
+linebuf::fromargv (av& newargv, char *real_path, bool cmdlenoverflow_ok)
 {
   bool success = true;
   for (int i = 0; i < newargv.argc; i++)
@@ -110,7 +114,7 @@ linebuf::fromargv (av& newargv, char *real_path)
       add (" ", 1);
     }
 
-  finish ();
+  finish (cmdlenoverflow_ok);
 
   if (ix >= MAXWINCMDLEN)
     {
diff --git a/winsup/cygwin/winf.h b/winsup/cygwin/winf.h
index 3b7fec23b..209091468 100644
--- a/winsup/cygwin/winf.h
+++ b/winsup/cygwin/winf.h
@@ -9,6 +9,14 @@ details. */
 #ifndef _WINF_H
 #define _WINF_H
 
+/* Hack for Cygwin processes.  If the Windows command line length gets slightly
+   bigger than this value, the stack position is suddenly moved up by 64K for
+   no apparent reason, which results in subsequent forks failing.  Since Cygwin
+   processes get the full command line as argv array anyway, this only affects
+   the maximum command line length of Cygwin applications which non-sensically
+   have a WinMain instead of a main entry point. */
+#define MAXCYGWINCMDLEN 31767
+
 #define MAXWINCMDLEN 32767
 #define LINE_BUF_CHUNK (CYG_MAX_PATH * 2)
 
@@ -74,8 +82,8 @@ class linebuf
   void add (const char *what, int len) __attribute__ ((regparm (3)));
   void add (const char *what) {add (what, strlen (what));}
   void prepend (const char *what, int len);
-  void finish () __attribute__ ((regparm (1)));
-  bool fromargv(av&, char *);
+  void finish (bool) __attribute__ ((regparm (2)));
+  bool fromargv(av&, char *, bool) __attribute__ ((regparm (3)));;
   operator char *() {return buf;}
 };