remove CPM_RESET in favor of CPM_OFFLINE (#6)

* remove CPM_RESET in favor of CPM_OFFLINE

* Update README.md (#5)

* Update README.md

* Update README.md

* Update README.md

README.md

@@ -2,7 +2,7 @@
 
 # CPM
 
-CPM is a very simple package manager written in Cmake based on the amazing [DownloadProject](https://github.com/Crascit/DownloadProject) script. It is extremely easy to use and drastically simplifies the inclusion of other Cmake-based projects from github.
+CPM is a minimalistic package manager written in Cmake based on the amazing [DownloadProject](https://github.com/Crascit/DownloadProject) script. It is extremely easy to use and drastically simplifies the inclusion of other Cmake-based projects from github.
 
 # Usage
 
@@ -18,7 +18,7 @@ include(${CMAKE_CURRENT_SOURCE_DIR}/cmake/CPM.cmake)
 
 CPMAddPackage(
   NAME LarsParser
-  VERSION 1.2
+  VERSION 1.4
   GIT_REPOSITORY https://github.com/TheLartians/Parser.git
   GIT_TAG master # optional
 )
@@ -29,7 +29,25 @@ add_executable(my-parser my-parser.cpp)
 target_link_libraries(cpm-test LarsParser)
 ```
 
+# Offline mode
+
+After including CPM CMake will try to update remote repositories at every new buld. To continue working offline, set the parameter `CPM_OFFLINE=On`. 
+
+# Installation
+
+To add CPM to your current project, copy the scripts in the `cmake` directory into you current project project. The command below will perform this automatically.
+
+```bash
+wget -qO- https://github.com/TheLartians/CPM/releases/download/v0.4/cmake.zip | bsdtar -xvf-
+```
+
+# Advantages
+
+- **Auto handle dependencies** Users of your projects do not need to worry about dependencies, everything is handled automatically.
+- **Reproducable builds** Using git tags it is ensured that a project will always be in the same state everywhere.
+- **No installation required** No need to install any third-party package managers. Just copy the files from the CMake directory and you're good to go.
+
 # Limitations
 
-- First version used: in diamond dependency graphs (e.g. `A` depends on `C`(v1.1) and `A` depends on `B` depends on `C`(v1.2)) the first added dependency will be used (in this case `C`@1.1).
-- No possibility not automatically update dependencies. To update a dependency, version numbers or git tags in the cmake scripts must be adapted manually.
+- **First version used** In diamond-shaped dependency graphs (e.g. `A` depends on `C`(v1.1) and `A` depends on `B` depends on `C`(v1.2)) the first added dependency will be used (in this case `C`@1.1).
+- **No auto-update** To update a dependency, version numbers or git tags in the cmake scripts must be adapted manually.

cmake/CPM.cmake

@@ -3,9 +3,11 @@ set(_CPM_Dir "${CMAKE_CURRENT_LIST_DIR}")
 include(CMakeParseArguments)
 include(${_CPM_Dir}/DownloadProject.cmake)
   
-function(CPMHasPackage) 
+option(CPM_OFFLINE "CPM offline mode" OFF)
 
-endfunction()
+if(NOT ${CPM_OFFLINE})
+  set(CPM_PACKAGES "" CACHE INTERNAL "CPM Packages")
+endif()
 
 function(CPMAddPackage)
   set(options QUIET)
@@ -16,6 +18,7 @@ function(CPMAddPackage)
     VERSION
     GIT_TAG
     BINARY_DIR
+    UPDATE_DISCONNECTED
   )
 
   set(multiValueArgs "")
@@ -30,8 +33,6 @@ function(CPMAddPackage)
     set(CPM_ARGS_BINARY_DIR ${CMAKE_BINARY_DIR}/CPM-projects/${CPM_ARGS_NAME})
   endif()
 
-  message("test: ${CPM_ARGS_BINARY_DIR}")
-
   if (NOT CPM_PROJECT_DIR)
     set(CPM_PROJECT_DIR "${CPM_ARGS_BINARY_DIR}")
   endif()

cmake/CPMProject.CMakeLists.cmake.in

@@ -17,7 +17,7 @@ else()
     PROJ @CPM_ARGS_NAME@
     GIT_REPOSITORY @CPM_ARGS_GIT_REPOSITORY@
     GIT_TAG @CPM_ARGS_GIT_TAG@
-    UPDATE_DISCONNECTED 1
+    UPDATE_DISCONNECTED @CPM_OFFLINE@
     GIT_SHALLOW 1
     PREFIX @CPM_ARGS_BINARY_DIR@/dl
     QUIET

tests/complex/CMakeLists.txt

@@ -7,7 +7,7 @@ include(${CMAKE_CURRENT_SOURCE_DIR}/../../cmake/CPM.cmake)
 CPMAddPackage(
   NAME LHC
   GIT_REPOSITORY https://github.com/TheLartians/LHC.git
-  VERSION 0.3
+  VERSION 0.4
 )
 
 CPMAddPackage(
@@ -21,14 +21,14 @@ CPMAddPackage(
 CPMAddPackage(
   NAME LarsParser
   GIT_REPOSITORY https://github.com/TheLartians/Parser.git
-  VERSION 1.3
+  VERSION 1.4
 )
 
-# add project twice
+# add project twice (will be ignored)
 CPMAddPackage(
   NAME LHC
   GIT_REPOSITORY https://github.com/TheLartians/LHC.git
-  VERSION 0.3
+  VERSION 0.1
 )
 
 # add executable

tests/simple/CMakeLists.txt

@@ -8,7 +8,7 @@ include(${CMAKE_CURRENT_SOURCE_DIR}/../../cmake/CPM.cmake)
 CPMAddPackage(
   NAME LarsParser
   GIT_REPOSITORY https://github.com/TheLartians/Parser.git
-  VERSION 1.3
+  VERSION 1.4
 )
 
 # add executable