Add support for specifying child process cwd and env to wxExecute().

Add an optional wxExecuteEnv parameter to wxExecute() which allows to specify
the initial working directory and custom environment for the child process.

Closes #12163.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@65896 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/utilsexc.cpp

@@ -610,7 +610,8 @@ wxExecuteDDE(const wxString& ddeServer,
 
 #endif // wxUSE_IPC
 
-long wxExecute(const wxString& cmd, int flags, wxProcess *handler)
+long wxExecute(const wxString& cmd, int flags, wxProcess *handler,
+               const wxExecuteEnv *env)
 {
     wxCHECK_MSG( !cmd.empty(), 0, wxT("empty command in wxExecute") );
 
@@ -800,6 +801,55 @@ long wxExecute(const wxString& cmd, int flags, wxProcess *handler)
     wxString arguments = command.AfterFirst(wxT(' '));
 #endif
 
+    wxWxCharBuffer envBuffer;
+    bool useCwd = false;
+    if ( env )
+    {
+        useCwd = !env->cwd.empty();
+
+        // Translate environment variable map into NUL-terminated list of
+        // NUL-terminated strings.
+        if ( !env->env.empty() )
+        {
+#if wxUSE_UNICODE
+            // Environment variables can contain non-ASCII characters. We could
+            // check for it and not use this flag if everything is really ASCII
+            // only but there doesn't seem to be any reason to do it so just
+            // assume Unicode by default.
+            dwFlags |= CREATE_UNICODE_ENVIRONMENT;
+#endif // wxUSE_UNICODE
+
+            wxEnvVariableHashMap::const_iterator it;
+
+            size_t envSz = 1; // ending '\0'
+            for ( it = env->env.begin(); it != env->env.end(); ++it )
+            {
+                // Add size of env variable name and value, and '=' char and
+                // ending '\0'
+                envSz += it->first.length() + it->second.length() + 2;
+            }
+
+            envBuffer.extend(envSz);
+
+            wxChar *p = envBuffer.data();
+            for ( it = env->env.begin(); it != env->env.end(); ++it )
+            {
+                const wxString line = it->first + wxS("=") + it->second;
+
+                // Include the trailing NUL which will always terminate the
+                // buffer returned by t_str().
+                const size_t len = line.length() + 1;
+
+                wxTmemcpy(p, line.t_str(), len);
+
+                p += len;
+            }
+
+            // And another NUL to terminate the list of NUL-terminated strings.
+            *p = 0;
+        }
+    }
+
     bool ok = ::CreateProcess
                 (
                     // WinCE requires appname to be non null
@@ -818,8 +868,10 @@ long wxExecute(const wxString& cmd, int flags, wxProcess *handler)
                  NULL,               //   the process and its main thread
                  redirect,           // inherit handles if we use pipes
                  dwFlags,            // process creation flags
-                 NULL,               // environment (use the same)
-                 NULL,               // current directory (use the same)
+                 envBuffer.data(),   // environment (may be NULL which is fine)
+                 useCwd              // initial working directory
+                    ? const_cast<wxChar *>(env->cwd.wx_str())
+                    : NULL,          //     (or use the same)
                  &si,                // startup info (unused here)
                  &pi                 // process info
                 ) != 0;
@@ -1039,7 +1091,8 @@ long wxExecute(const wxString& cmd, int flags, wxProcess *handler)
 }
 
 template <typename CharType>
-long wxExecuteImpl(CharType **argv, int flags, wxProcess *handler)
+long wxExecuteImpl(CharType **argv, int flags, wxProcess *handler,
+                   const wxExecuteEnv *env)
 {
     wxString command;
     command.reserve(1024);
@@ -1078,19 +1131,21 @@ long wxExecuteImpl(CharType **argv, int flags, wxProcess *handler)
         command += ' ';
     }
 
-    return wxExecute(command, flags, handler);
+    return wxExecute(command, flags, handler, env);
 }
 
-long wxExecute(char **argv, int flags, wxProcess *handler)
+long wxExecute(char **argv, int flags, wxProcess *handler,
+               const wxExecuteEnv *env)
 {
-    return wxExecuteImpl(argv, flags, handler);
+    return wxExecuteImpl(argv, flags, handler, env);
 }
 
 #if wxUSE_UNICODE
 
-long wxExecute(wchar_t **argv, int flags, wxProcess *handler)
+long wxExecute(wchar_t **argv, int flags, wxProcess *handler,
+               const wxExecuteEnv *env)
 {
-    return wxExecuteImpl(argv, flags, handler);
+    return wxExecuteImpl(argv, flags, handler, env);
 }
 
 #endif // wxUSE_UNICODE