If the --script argument passed to the updater is relative, interpret it as being relative to the package dir rather than the directory that the updater is run from.

Mendeley Desktop <= 1.0 clients pass a relative path for the script argument but
run the updater from the directory containing the main application binary instead
of the package dir.  The script argument, if relative, is therefore treated as
relative to the package directory.

src/DirIterator.cpp

@@ -9,12 +9,6 @@
 
 #include <string.h>
 
-bool endsWith(const std::string& str, const char* text)
-{
-	size_t length = strlen(text);
-	return str.find(text,str.size() - length) != 0;
-}
-
 DirIterator::DirIterator(const char* path)
 {
 	m_path = path;

src/FileUtils.cpp

@@ -410,3 +410,49 @@ std::string FileUtils::tempPath()
 #endif
 }
 
+bool startsWithDriveLetter(const char* path)
+{
+	return strlen(path) >= 2 &&
+	      (path[0] >= 'A' && path[0] <= 'Z') &&
+	       path[1] == ':';
+}
+
+bool FileUtils::isRelative(const char* path)
+{
+#ifdef PLATFORM_UNIX
+	return strlen(path) == 0 || path[0] != '/';
+#else
+	// on Windows, a path is relative if it does not start with:
+	// - '\\' (a UNC name)
+	// - '[Drive Letter]:\'
+	// - A single backslash
+	//
+	// the input path is assumed to have already been converted to use
+	// Unix-style path separators
+
+	std::string pathStr(path);
+
+	if ((!pathStr.empty() && pathStr.at(0) == '/') ||
+	    (startsWith(pathStr,"//")) ||
+	    (startsWithDriveLetter(pathStr.c_str())))
+	{
+		return false;
+	}
+	else
+	{
+		return true;
+	}
+#endif
+}
+
+std::string FileUtils::makeAbsolute(const char* path, const char* basePath)
+{
+	if (isRelative(path))
+	{
+		return std::string(basePath) + '/' + std::string(path);
+	}
+	else
+	{
+		return path;
+	}
+}

src/FileUtils.h

@@ -7,6 +7,9 @@
 
 /** A set of functions for performing common operations
   * on files, throwing exceptions if an operation fails.
+  *
+  * Path arguments to FileUtils functions should use Unix-style path
+  * separators.
   */
 class FileUtils
 {
@@ -102,6 +105,18 @@ class FileUtils
 		 */
 		static std::string toUnixPathSeparators(const std::string& str);
 
+		/** Returns true if the provided path is relative.
+		  * Or false if absolute.
+		  */
+		static bool isRelative(const char* path);
+
+		/** Converts @p path to an absolute path.  If @p path is already absolute,
+		  * just returns @p path, otherwise prefixes it with @p basePath to make it absolute.
+		  *
+		  * @p basePath should be absolute.
+		  */
+		static std::string makeAbsolute(const char* path, const char* basePath);
+
 	private:
 		static int toUnixPermissions(int qtPermissions);
 };

src/StringUtils.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include <string.h>
 #include <string>
 #include <sstream>
 #include <stdlib.h>
@@ -32,3 +33,14 @@ inline const char* notNullString(const char* text)
 	}
 }
 
+inline bool endsWith(const std::string& str, const char* text)
+{
+	size_t length = strlen(text);
+	return str.find(text,str.size() - length) != 0;
+}
+
+inline bool startsWith(const std::string& str, const char* text)
+{
+	return str.find(text,0) == 0;
+}
+

src/main.cpp

@@ -1,4 +1,5 @@
 #include "AppInfo.h"
+#include "FileUtils.h"
 #include "Log.h"
 #include "Platform.h"
 #include "ProcessUtils.h"
@@ -63,7 +64,7 @@ int main(int argc, char** argv)
 
 	if (!options.scriptPath.empty())
 	{
-		script.parse(options.scriptPath);
+		script.parse(FileUtils::makeAbsolute(options.scriptPath.c_str(),options.packageDir.c_str()));
 	}
 
 	LOG(Info,"started updater. install-dir: " + options.installDir

src/tests/test-update.rb

@@ -3,8 +3,8 @@
 require 'fileutils.rb'
 require 'rbconfig'
 
-INSTALL_DIR = "install-dir/"
-PACKAGE_DIR = "package-dir/"
+INSTALL_DIR = File.expand_path("install-dir/")
+PACKAGE_DIR = File.expand_path("package-dir/")
 
 if (RbConfig::CONFIG['host_os'] =~ /mswin|mingw/)
 	OLDAPP_NAME = "oldapp.exe"
@@ -61,7 +61,14 @@ replace_vars("file_list.xml","#{PACKAGE_DIR}/file_list.xml",file_list_vars)
 FileUtils.cp("../#{UPDATER_NAME}","#{PACKAGE_DIR}/#{UPDATER_NAME}")
 
 # Run the updater using the new syntax
-system("#{PACKAGE_DIR}/#{UPDATER_NAME} --install-dir #{INSTALL_DIR} --package-dir #{PACKAGE_DIR} --script #{PACKAGE_DIR}/file_list.xml")
+#
+# Run the application from the install directory to
+# make sure that it looks in the correct directory for
+# the file_list.xml file and packages
+#
+Dir.chdir(INSTALL_DIR) do
+	system("#{PACKAGE_DIR}/#{UPDATER_NAME} --install-dir #{INSTALL_DIR} --package-dir #{PACKAGE_DIR} --script file_list.xml")
+end
 
 # TODO - Correctly wait until updater has finished
 sleep(1)