fix: Move Windows config and cache to LOCALAPPDATA

Throw a fatal error if a cache is detected in APPDATA.

Fix-up default cmake install directories and set system-wide config to
C:\ProgramData\ccache\ccache.conf .

Update manual.

Fix ccache#1023
Fix ccache#946

Signed-off-by: Rafael Kitover <rkitover@gmail.com>

CMakeLists.txt

@@ -75,7 +75,8 @@ include(DefaultBuildType)
 #
 # Configuration
 #
-include(GNUInstallDirs)
+
+include(InstallDirs)
 include(GenerateConfigurationFile)
 include(GenerateVersionFile)
 

cmake/InstallDirs.cmake

@@ -0,0 +1,27 @@
+if(WIN32)
+  set(programfiles "$ENV{ProgramFiles}")
+
+  # For 32 bit builds.
+  if(CMAKE_C_SIZEOF_DATA_PTR EQUAL 4 AND ENV{ProgramFiles\(x86\)})
+    set(programfiles "$ENV{ProgramFiles\(x86\)}")
+  endif()
+
+  string(REPLACE "\\" "\\\\" programfiles "${programfiles}")
+
+  set(CMAKE_INSTALL_PREFIX "${programfiles}\\\\ccache" CACHE STRING "System-wide installation location" FORCE)
+
+  if(NOT CMAKE_INSTALL_SYSCONFDIR)
+    string(REPLACE "\\" "\\\\" programdata "$ENV{ALLUSERSPROFILE}")
+    if(NOT programdata)
+      set(programdata "C:\\\\ProgramData")
+    endif()
+
+    set(CMAKE_INSTALL_SYSCONFDIR "${programdata}\\\\ccache" CACHE STRING "Systemwide configuration location" FORCE)
+  endif()
+
+  set(CMAKE_INSTALL_BINDIR     "" CACHE PATH "" FORCE)
+  set(CMAKE_INSTALL_LIBEXECDIR "" CACHE PATH "" FORCE)
+  set(CMAKE_INSTALL_SBINDIR    "" CACHE PATH "" FORCE)
+endif()
+
+include(GNUInstallDirs)

doc/MANUAL.adoc

@@ -309,12 +309,17 @@ this:
 2. Otherwise, if the environment variable `CCACHE_DIR` is set then use
    `$CCACHE_DIR/ccache.conf`.
 3. Otherwise, if <<config_cache_dir,*cache_dir*>> is set in the secondary
-   (system-wide) configuration file then use `<cache_dir>/ccache.conf`.
+   (system-wide) configuration file then use `<cache_dir>/ccache.conf`. The
+   system-wide configuration on Windows is
+   `$env:ALLUSERSPROFILE\ccache\ccache.conf` by default, `$env:ALLUSERSPROFILE`
+   is usually `C:\ProgramData`.
 4. Otherwise, if there is a legacy `$HOME/.ccache` directory then use
-   `$HOME/.ccache/ccache.conf`.
-5. Otherwise, if `XDG_CONFIG_HOME` is set then use
-   `$XDG_CONFIG_HOME/ccache/ccache.conf`.
-6. Otherwise, use `%APPDATA%/ccache/ccache.conf` (Windows),
+   `$HOME/.ccache/ccache.conf` (`$env:USERPROFILE` on Windows.)
+6. Otherwise, if `XDG_CONFIG_HOME` is set then use
+   `$XDG_CONFIG_HOME/ccache/ccache.conf`. On Windows
+   `$env:LOCALAPPDATA\ccache\ccache.conf` is used first if it exists, otherwise
+   `$env:APPDATA\ccache\ccache.conf` is used if it exists.
+6. Otherwise, for systems other than Windows, use 
    `$HOME/Library/Preferences/ccache/ccache.conf` (macOS) or
    `$HOME/.config/ccache/ccache.conf` (other systems).
 

src/Config.cpp

@@ -424,29 +424,27 @@ parse_config_file(const std::string& path,
 
 } // namespace
 
+#ifndef _WIN32
 static std::string
 default_cache_dir(const std::string& home_dir)
 {
-#ifdef _WIN32
-  return home_dir + "/ccache";
-#elif defined(__APPLE__)
+#  ifdef __APPLE__
   return home_dir + "/Library/Caches/ccache";
-#else
+#  else
   return home_dir + "/.cache/ccache";
-#endif
+#  endif
 }
 
 static std::string
 default_config_dir(const std::string& home_dir)
 {
-#ifdef _WIN32
-  return home_dir + "/ccache";
-#elif defined(__APPLE__)
+#  ifdef __APPLE__
   return home_dir + "/Library/Preferences/ccache";
-#else
+#  else
   return home_dir + "/.config/ccache";
-#endif
+#  endif
 }
+#endif
 
 std::string
 compiler_type_to_string(CompilerType compiler_type)
@@ -477,11 +475,16 @@ void
 Config::read()
 {
   const std::string home_dir = Util::get_home_directory();
-  const std::string legacy_ccache_dir = home_dir + "/.ccache";
+  const std::string legacy_ccache_dir = home_dir + DIR_SEP + ".ccache";
   const bool legacy_ccache_dir_exists =
     Stat::stat(legacy_ccache_dir).is_directory();
+#ifdef _WIN32
+  const char* const env_appdata = getenv("APPDATA");
+  const char* const env_local_appdata = getenv("LOCALAPPDATA");
+#else
   const char* const env_xdg_cache_home = getenv("XDG_CACHE_HOME");
   const char* const env_xdg_config_home = getenv("XDG_CONFIG_HOME");
+#endif
 
   const char* env_ccache_configpath = getenv("CCACHE_CONFIGPATH");
   if (env_ccache_configpath) {
@@ -490,9 +493,9 @@ Config::read()
     // Only used for ccache tests:
     const char* const env_ccache_configpath2 = getenv("CCACHE_CONFIGPATH2");
 
-    set_secondary_config_path(env_ccache_configpath2
-                                ? env_ccache_configpath2
-                                : FMT("{}/ccache.conf", k_sysconfdir));
+    set_secondary_config_path(
+      env_ccache_configpath2 ? env_ccache_configpath2
+                             : FMT("{}{}ccache.conf", k_sysconfdir, DIR_SEP));
     MTR_BEGIN("config", "conf_read_secondary");
     // A missing config file in SYSCONFDIR is OK so don't check return value.
     update_from_file(secondary_config_path());
@@ -506,12 +509,32 @@ Config::read()
       primary_config_dir = cache_dir();
     } else if (legacy_ccache_dir_exists) {
       primary_config_dir = legacy_ccache_dir;
+#ifdef _WIN32
+    } else if (env_local_appdata
+               && Stat::stat(FMT("{}{}ccache{}ccache.conf",
+                                 env_local_appdata,
+                                 DIR_SEP,
+                                 DIR_SEP))) {
+      primary_config_dir = FMT("{}{}ccache", env_local_appdata, DIR_SEP);
+    } else if (env_appdata
+               && Stat::stat(FMT(
+                 "{}{}ccache{}ccache.conf", env_appdata, DIR_SEP, DIR_SEP))) {
+      primary_config_dir = FMT("{}{}ccache", env_appdata, DIR_SEP);
+    } else if (env_local_appdata) {
+      primary_config_dir = FMT("{}{}ccache", env_local_appdata, DIR_SEP);
+    } else {
+      throw core::Error(
+        "could not find config file and the LOCALAPPDATA "
+        "environment variable is not set");
+    }
+#else
     } else if (env_xdg_config_home) {
-      primary_config_dir = FMT("{}/ccache", env_xdg_config_home);
+      primary_config_dir = FMT("{}{}ccache", env_xdg_config_home, DIR_SEP);
     } else {
       primary_config_dir = default_config_dir(home_dir);
     }
-    set_primary_config_path(primary_config_dir + "/ccache.conf");
+#endif
+    set_primary_config_path(primary_config_dir + DIR_SEP + "ccache.conf");
   }
 
   const std::string& cache_dir_before_primary_config = cache_dir();
@@ -531,12 +554,38 @@ Config::read()
   if (cache_dir().empty()) {
     if (legacy_ccache_dir_exists) {
       set_cache_dir(legacy_ccache_dir);
+#ifdef _WIN32
+    } else if (env_local_appdata) {
+      set_cache_dir(FMT("{}{}ccache", env_local_appdata, DIR_SEP));
+    } else {
+      throw core::Error(
+        "could not find cache dir and the LOCALAPPDATA "
+        "environment variable is not set");
+    }
+#else
     } else if (env_xdg_cache_home) {
-      set_cache_dir(FMT("{}/ccache", env_xdg_cache_home));
+      set_cache_dir(FMT("{}{}ccache", env_xdg_cache_home, DIR_SEP));
     } else {
       set_cache_dir(default_cache_dir(home_dir));
     }
+#endif
   }
+
+  // Check for previous default cachedir in APPDATA and throw a fatal error if
+  // it exists.
+#ifdef _WIN32
+  if (const char* appdata = getenv("APPDATA")) {
+    if (Stat::stat(FMT("{}{}ccache{}tmp", appdata, DIR_SEP, DIR_SEP)))
+      throw core::Error(
+        "legacy cache detected in APPDATA directory {}{}ccache, "
+        "please move it to the LOCALAPPDATA directory {}{}ccache",
+        appdata,
+        DIR_SEP,
+        getenv("LOCALAPPDATA"),
+        DIR_SEP);
+  }
+#endif
+
   // else: cache_dir was set explicitly via environment or via secondary
   // config.
 

src/Util.cpp

@@ -665,16 +665,14 @@ get_extension(std::string_view path)
 std::string
 get_home_directory()
 {
-  const char* p = getenv("HOME");
-  if (p) {
-    return p;
-  }
 #ifdef _WIN32
-  p = getenv("APPDATA");
-  if (p) {
+  if (const char* p = getenv("USERPROFILE"))
+#else
+  if (const char* p = getenv("HOME"))
+#endif
+  {
     return p;
   }
-#endif
 #ifdef HAVE_GETPWUID
   {
     struct passwd* pwd = getpwuid(getuid());

src/Util.hpp

@@ -33,6 +33,13 @@
 
 class Context;
 
+// Constant for the system directory separator.
+#ifdef _WIN32
+const char DIR_SEP = '\\';
+#else
+const char DIR_SEP = '/';
+#endif
+
 namespace Util {
 
 using DataReceiver = std::function<void(const void* data, size_t size)>;