tests: make it possible to set executable extensions

This enables the use of Windows Subsystem for Linux (WSL) to run the
testsuite against Windows binaries while using Linux servers.

This commit introduces the following environment variables:
- CURL_TEST_EXE_EXT: set the executable extension for all components
- CURL_TEST_EXE_EXT_TOOL: set it for the curl tool only
- CURL_TEST_EXE_EXT_SSH: set it for the SSH tools only

Later testcurl.pl could be adjusted to make use of those variables.
- CURL_TEST_EXE_EXT_SRV: set it for the test servers only

(This is one of several commits to support use of WSL for the tests.)

Closes https://github.com/curl/curl/pull/3899

4 files changed, 36 insertions, 17 deletions

diff --git a/tests/ftpserver.pl b/tests/ftpserver.pl
index d401be24c..ac02722e9 100755
--- a/tests/ftpserver.pl
+++ b/tests/ftpserver.pl
@@ -68,6 +68,10 @@ use serverhelp qw(
     datasockf_logfilename
     );
 
+use sshhelp qw(
+    exe_ext
+    );
+
 #**********************************************************************
 # global vars...
 #
@@ -411,7 +415,7 @@ sub sysread_or_die {
 }
 
 sub startsf {
-    my $mainsockfcmd = "./server/sockfilt " .
+    my $mainsockfcmd = "./server/sockfilt".exe_ext('SRV')." " .
         "--ipv$ipvnum --port $port " .
         "--pidfile \"$mainsockf_pidfile\" " .
         "--logfile \"$mainsockf_logfile\"";
@@ -2401,7 +2405,7 @@ sub PASV_ftp {
     logmsg "DATA sockfilt for passive data channel starting...\n";
 
     # We fire up a new sockfilt to do the data transfer for us.
-    my $datasockfcmd = "./server/sockfilt " .
+    my $datasockfcmd = "./server/sockfilt".exe_ext('SRV')." " .
         "--ipv$ipvnum $bindonly --port 0 " .
         "--pidfile \"$datasockf_pidfile\" " .
         "--logfile \"$datasockf_logfile\"";
@@ -2620,7 +2624,7 @@ sub PORT_ftp {
     logmsg "DATA sockfilt for active data channel starting...\n";
 
     # We fire up a new sockfilt to do the data transfer for us.
-    my $datasockfcmd = "./server/sockfilt " .
+    my $datasockfcmd = "./server/sockfilt".exe_ext('SRV')." " .
         "--ipv$ipvnum --connect $port --addr \"$addr\" " .
         "--pidfile \"$datasockf_pidfile\" " .
         "--logfile \"$datasockf_logfile\"";
diff --git a/tests/httpserver.pl b/tests/httpserver.pl
index 7f6c86a8a..8b789a9b9 100755
--- a/tests/httpserver.pl
+++ b/tests/httpserver.pl
@@ -34,6 +34,10 @@ use serverhelp qw(
     server_logfilename
     );
 
+use sshhelp qw(
+    exe_ext
+    );
+
 my $verbose = 0;     # set to 1 for debugging
 my $port = 8990;     # just a default
 my $unix_socket;     # location to place a listening Unix socket
@@ -133,7 +137,7 @@ if($ipvnum eq 'unix') {
 $flags .= "--srcdir \"$srcdir\"";
 
 if($verbose) {
-    print STDERR "RUN: server/sws $flags\n";
+    print STDERR "RUN: server/sws".exe_ext('SRV')." $flags\n";
 }
 
-exec("server/sws $flags");
+exec("server/sws".exe_ext('SRV')." $flags");
diff --git a/tests/runtests.pl b/tests/runtests.pl
index 737fbe27e..961cdb753 100755
--- a/tests/runtests.pl
+++ b/tests/runtests.pl
@@ -150,7 +150,7 @@ my $SMBSPORT;            # SMBS server port
 my $NEGTELNETPORT;       # TELNET server port with negotiation
 
 my $srcdir = $ENV{'srcdir'} || '.';
-my $CURL="../src/curl".exe_ext(); # what curl executable to run on the tests
+my $CURL="../src/curl".exe_ext('TOOL'); # what curl executable to run on the tests
 my $VCURL=$CURL;   # what curl binary to use to verify the servers with
                    # VCURL is handy to set to the system one when the one you
                    # just built hangs or crashes and thus prevent verification
@@ -2915,7 +2915,8 @@ sub checksystem {
         # client has IPv6 support
 
         # check if the HTTP server has it!
-        my @sws = `server/sws --version`;
+        my $cmd = "server/sws".exe_ext('SRV')." --version";
+        my @sws = `$cmd`;
         if($sws[0] =~ /IPv6/) {
             # HTTP server has IPv6 support!
             $http_ipv6 = 1;
@@ -2923,7 +2924,8 @@ sub checksystem {
         }
 
         # check if the FTP server has it!
-        @sws = `server/sockfilt --version`;
+        $cmd = "server/sockfilt".exe_ext('SRV')." --version";
+        @sws = `$cmd`;
         if($sws[0] =~ /IPv6/) {
             # FTP server has IPv6 support!
             $ftp_ipv6 = 1;
@@ -2932,7 +2934,8 @@ sub checksystem {
 
     if($has_unix) {
         # client has Unix sockets support, check whether the HTTP server has it
-        my @sws = `server/sws --version`;
+        my $cmd = "server/sws".exe_ext('SRV')." --version";
+        my @sws = `$cmd`;
         $http_unix = 1 if($sws[0] =~ /unix/);
     }
 
@@ -3342,7 +3345,7 @@ sub singletest {
                 }
                 else {
                     if($var =~ /^LD_PRELOAD/) {
-                        if(exe_ext() && (exe_ext() eq '.exe')) {
+                        if(exe_ext('TOOL') && (exe_ext('TOOL') eq '.exe')) {
                             # print "Skipping LD_PRELOAD due to lack of OS support\n";
                             next;
                         }
@@ -3489,6 +3492,7 @@ sub singletest {
     if(@codepieces) {
         $tool = $codepieces[0];
         chomp $tool;
+        $tool .= exe_ext('TOOL');
     }
 
     # remove server output logfile
diff --git a/tests/sshhelp.pm b/tests/sshhelp.pm
index 47ea2324c..248be67a2 100644
--- a/tests/sshhelp.pm
+++ b/tests/sshhelp.pm
@@ -106,12 +106,12 @@ use vars qw(
 #***************************************************************************
 # Global variables initialization
 #
-$sshdexe         = 'sshd'        .exe_ext(); # base name and ext of ssh daemon
-$sshexe          = 'ssh'         .exe_ext(); # base name and ext of ssh client
-$sftpsrvexe      = 'sftp-server' .exe_ext(); # base name and ext of sftp-server
-$sftpexe         = 'sftp'        .exe_ext(); # base name and ext of sftp client
-$sshkeygenexe    = 'ssh-keygen'  .exe_ext(); # base name and ext of ssh-keygen
-$httptlssrvexe   = 'gnutls-serv' .exe_ext(); # base name and ext of gnutls-serv
+$sshdexe         = 'sshd'        .exe_ext('SSH'); # base name and ext of ssh daemon
+$sshexe          = 'ssh'         .exe_ext('SSH'); # base name and ext of ssh client
+$sftpsrvexe      = 'sftp-server' .exe_ext('SSH'); # base name and ext of sftp-server
+$sftpexe         = 'sftp'        .exe_ext('SSH'); # base name and ext of sftp client
+$sshkeygenexe    = 'ssh-keygen'  .exe_ext('SSH'); # base name and ext of ssh-keygen
+$httptlssrvexe   = 'gnutls-serv' .exe_ext('SSH'); # base name and ext of gnutls-serv
 $sshdconfig      = 'curl_sshd_config';       # ssh daemon config file
 $sshconfig       = 'curl_ssh_config';        # ssh client config file
 $sftpconfig      = 'curl_sftp_config';       # sftp client config file
@@ -180,6 +180,13 @@ $clipubkeyf      = 'curl_client_key.pub';    # client public key file
 # Return file extension for executable files on this operating system
 #
 sub exe_ext {
+    my ($component, @arr) = @_;
+    if ($ENV{'CURL_TEST_EXE_EXT'}) {
+        return $ENV{'CURL_TEST_EXE_EXT'};
+    }
+    if ($ENV{'CURL_TEST_EXE_EXT_'.$component}) {
+        return $ENV{'CURL_TEST_EXE_EXT_'.$component};
+    }
     if ($^O eq 'MSWin32' || $^O eq 'cygwin' || $^O eq 'msys' ||
         $^O eq 'dos' || $^O eq 'os2') {
         return '.exe';
@@ -314,7 +321,7 @@ sub find_exe_file {
     my $fn = $_[0];
     shift;
     my @path = @_;
-    my $xext = exe_ext();
+    my $xext = exe_ext('SSH');
     foreach (@path) {
         my $file = File::Spec->catfile($_, $fn);
         if(-e $file && ! -d $file) {