[Fixed JENKINS-21806] Improve ssh.exe finding on Windows with msysgit

Adapt to msysgit installed in non-default locations, and to msysgit alternative configurations as allowed by the msysgit installer. The mssygit installer allows the user to choose to make no changes to the PATH, or to add the "cmd" directory to the PATH, or add the "bin" directory to the PATH. If the user chooses to make no changes to the PATH, then they configure their Jenkins git with the absolute path of the git executable. If the user chooses to add the "cmd" directory to the PATH, then they configure their Jenkins git with the executable as "git", "git.exe", or (with some msysgit versions) "git.cmd". If the user chooses to add the "bin" directory to the PATH, then they configure similarly to the "cmd" directory case. The plugin attempts to handle all those cases correctly. Special thanks to Thiago Zanetti for providing the original code for this fix.
jenkinsci · Jul 15, 2014 · 9430af7 · 9430af7 · thiagozanetti · Jul 15, 2014
1 parent 824d028
commit 9430af7
Show file tree

Hide file tree

Showing 2 changed files with 98 additions and 15 deletions.
diff --git a/src/main/java/org/jenkinsci/plugins/gitclient/CliGitAPIImpl.java b/src/main/java/org/jenkinsci/plugins/gitclient/CliGitAPIImpl.java
@@ -1258,26 +1258,99 @@ private File createUnixSshAskpass(SSHUserPrivateKey sshUser) throws IOException
         return ssh;
     }
 
+    private String getPathToExe(String userGitExe) {
+        userGitExe = userGitExe.toLowerCase();
+
+        String cmd;
+        String exe;
+        if (userGitExe.endsWith(".exe")) {
+            cmd = userGitExe.replace(".exe", ".cmd");
+            exe = userGitExe;
+        } else if (userGitExe.endsWith(".cmd")) {
+            cmd = userGitExe;
+            exe = userGitExe.replace(".cmd", ".exe");
+        } else {
+            cmd = userGitExe + ".cmd";
+            exe = userGitExe + ".exe";
+        }
 
-    private File createWindowsGitSSH(File key) throws IOException {
-        File ssh = File.createTempFile("ssh", ".bat");
-        // windows git installer place C:\Program Files\Git\cmd\git.exe in PATH
-
-        String progFiles = System.getenv("ProgramFiles");
-        String sshPath = "/Git/bin/ssh.exe";
-        File sshexe = new File(progFiles + sshPath);
-        if (!sshexe.exists()) {
-          // try the (x86) version for 64-bit Windows builds
-          sshexe = new File(progFiles + " (x86)" + sshPath);
+        String[] pathDirs = System.getenv("PATH").split(File.pathSeparator);
+
+        for (String pathDir : pathDirs) {
+            File exeFile = new File(pathDir, exe);
+            if (exeFile.exists()) {
+                return exeFile.getAbsolutePath();
+            }
+            File cmdFile = new File(pathDir, cmd);
+            if (cmdFile.exists()) {
+                return cmdFile.getAbsolutePath();
+            }
+        }
+
+        return null;
+    }
+
+    private File getFileFromEnv(String envVar, String suffix) {
+        String envValue = System.getenv(envVar);
+        if (envValue == null) {
+            return null;
         }
-        if (!sshexe.exists()) {
-		  // try the ssh.exe next to known git.exe
-		  sshexe = new File(new File(gitExe).getParentFile(), "ssh.exe");
+        return new File(envValue + suffix);       
+    }
+
+    private File getSSHExeFromGitExeParentDir(String userGitExe) {
+        String parentPath = new File(userGitExe).getParent();
+        if (parentPath == null) {
+            return null;
         }
+        return new File(parentPath + "\\ssh.exe");
+    }
 
-        if (!sshexe.exists()) {
-            throw new RuntimeException("git plugin only support official git client http://git-scm.com/download/win");
+    /* package */ File getSSHExecutable() {
+        // First check the GIT_SSH environment variable
+        File sshexe = getFileFromEnv("GIT_SSH", "");
+        if (sshexe != null && sshexe.exists()) {
+            return sshexe;
         }
+
+        // Check Program Files
+        sshexe = getFileFromEnv("ProgramFiles", "\\Git\\bin\\ssh.exe");
+        if (sshexe != null && sshexe.exists()) {
+            return sshexe;
+        }
+
+        // Check Program Files(x86) for 64 bit computer
+        sshexe = getFileFromEnv("ProgramFiles(x86)", "\\Git\\bin\\ssh.exe");
+        if (sshexe != null && sshexe.exists()) {
+            return sshexe;
+        }
+
+        // Search for an ssh.exe near the git executable.
+        sshexe = getSSHExeFromGitExeParentDir(gitExe);
+        if (sshexe != null && sshexe.exists()) {
+            return sshexe;
+        }
+
+        // Search for git on the PATH, then look near it
+        String gitPath = getPathToExe(gitExe);
+        if (gitPath != null) {
+            // In case we are using msysgit from the cmd directory
+            // instead of the bin directory, replace cmd with bin in
+            // the path while trying to find ssh.exe.
+            sshexe = getSSHExeFromGitExeParentDir(gitPath.replace("/cmd/", "/bin/").replace("\\cmd\\", "\\bin\\"));
+            if (sshexe != null && sshexe.exists()) {
+                return sshexe;
+            }
+        }
+
+        throw new RuntimeException("ssh executable not found. The git plugin only supports official git client http://git-scm.com/download/win");
+    }
+
+    private File createWindowsGitSSH(File key) throws IOException {
+        File ssh = File.createTempFile("ssh", ".bat");
+
+        File sshexe = getSSHExecutable();
+
         PrintWriter w = new PrintWriter(ssh);
         w .println("@echo off");
         w .println("\"" + sshexe.getAbsolutePath() + "\" -i \"" + key.getAbsolutePath() +"\" -o StrictHostKeyChecking=no %* ");

diff --git a/src/test/java/org/jenkinsci/plugins/gitclient/GitAPITestCase.java b/src/test/java/org/jenkinsci/plugins/gitclient/GitAPITestCase.java
@@ -2619,4 +2619,14 @@ public void test_longpaths_disabled() throws Exception {
         w.cmd("git config --add core.longpaths false");
         check_longpaths(false);
     }
+
+    @NotImplementedInJGit
+    /* Not implemented in JGit because it is not needed there */
+    public void test_git_ssh_executable_found_on_windows() throws Exception {
+        if (!SystemUtils.IS_OS_WINDOWS) {
+            return;
+        }
+
+        assertTrue("ssh.exe not found", w.cgit().getSSHExecutable().exists());
+    }
 }