[cmake-developers] [CMake 0014935]: file(APPEND "message...") writes nulls into file

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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http://public.kitware.com/Bug/view.php?id=14935 
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Reported By:                th.thielemann
Assigned To:                
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Project:                    CMake
Issue ID:                   14935
Category:                   CMake
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
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Date Submitted:             2014-05-26 04:56 EDT
Last Modified:              2014-05-26 04:56 EDT
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Summary:                    file(APPEND "message...") writes nulls into file
Description: 
I am using a shared folder between my Win7 and VmWare with Ubuntu 12.04. 
Fore some reasons I write out some properties into a file during cmake run.
First line with file(WRITE "key=value"). All others with file(APPEND ...)
Sucessful tested on Windows, Linux using the local file system. But if I share a
folder between Windows and Linux, the result is "00 00 00 00 ... 00 The appended
message".

Steps to Reproduce: 
Create the environment Win7 + VmWare + Ubuntu 12.04 LTS + shared folder.

Here is my function

function(write_env_script Mode EnvKey EnvValue)
    # Possible option flags
    list(FIND ARGN EXTEND IsExtend)

    # Resulting script name
	if(CMAKE_HOST_WIN32)
        file(TO_NATIVE_PATH ${EnvValue} EnvValue)
    endif()
	set(ScriptName ${PROJECT_BINARY_DIR}/setprojectenv${SSP_SCRIPT_TYPE})

    # Reset mode to WRITE if file does not exist
    if(("${Mode}" STREQUAL "APPEND") AND (NOT EXISTS ${ScriptName}))
        set(Mode "WRITE")
    endif()

    # overwrite or extend the env variable's value
    set(EnvValueAlreadySet -1)
    if(NOT IsExtend EQUAL -1)
        if(NOT "$ENV{${EnvKey}}" STREQUAL "")
            if(CMAKE_HOST_UNIX)
                set(CurrentEnvValue "$ENV{${EnvKey}}:")
            elseif(CMAKE_HOST_WIN32)
                set(CurrentEnvValue "$ENV{${EnvKey}};")
            endif()
        endif()
        # Contains the env variable the value already?
        string(FIND "$ENV{${EnvKey}}" "${EnvValue}" EnvValueAlreadySet REVERSE)
    endif()

    if(EnvValueAlreadySet EQUAL -1)
        if(CMAKE_HOST_UNIX)
#### Error! Replace the following line with workaround
						file(${Mode} ${ScriptName} "${PreviousScriptContent} export
${EnvKey}=${CurrentEnvValue}${EnvValue}\n" )
			execute_process(COMMAND chmod u+x ${ScriptName} WORKING_DIRECTORY
"${PROJECT_BINARY_DIR}")
        elseif(CMAKE_HOST_WIN32)
            file(${Mode} ${ScriptName} "set
${EnvKey}=${CurrentEnvValue}${EnvValue}\n\r" )
        endif()
    endif()
endfunction()


The workaround for linux using VmWare share.
			if("${Mode}" STREQUAL "APPEND")
				file(READ ${ScriptName} PreviousScriptContent)
			endif()
			file(WRITE ${ScriptName} "${PreviousScriptContent} export
${EnvKey}=${CurrentEnvValue}${EnvValue}\n" )


Usage of the function:
	write_env_script(APPEND QT_PLUGIN_PATH "${QtLibs_PATH}/plugins")
	write_env_script(APPEND QML2_IMPORT_PATH "${QtLibs_PATH}/qml")
	write_env_script(APPEND PATH "${QtLibs_PATH}/bin" EXTEND)
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Issue History 
Date Modified    Username       Field                    Change               
====================================================================== 
2014-05-26 04:56 th.thielemann  New Issue                                    
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