layers: Add environment var for settings file

Change-Id: I8a614f915ab9b61eca5b3b94f4cf43a33cacf250

1 files changed, 50 insertions, 6 deletions

diff --git a/layers/vk_layer_config.cpp b/layers/vk_layer_config.cpp
index ec50744d..d8fe87d2 100644
--- a/layers/vk_layer_config.cpp
+++ b/layers/vk_layer_config.cpp
@@ -21,14 +21,15 @@
  * Author: Tobin Ehlis <tobin@lunarg.com>
  * Author: Mark Lobodzinski <mark@lunarg.com>
  **************************************************************************/
+#include "vk_layer_config.h"
+#include "vulkan/vk_sdk_platform.h"
 #include <fstream>
-#include <string>
+#include <iostream>
 #include <map>
 #include <string.h>
+#include <string>
+#include <sys/stat.h>
 #include <vulkan/vk_layer.h>
-#include <iostream>
-#include "vk_layer_config.h"
-#include "vulkan/vk_sdk_platform.h"
 
 #define MAX_CHARS_PER_LINE 4096
 
@@ -49,6 +50,25 @@ class ConfigFile {
 
 static ConfigFile g_configFileObj;
 
+std::string getEnvironment(const char *variable) {
+#if !defined(__ANDROID__) && !defined(_WIN32)
+    const char *output = getenv(variable);
+    return output == NULL ? "" : output;
+#elif defined(_WIN32)
+    int size = GetEnvironmentVariable(variable, NULL, 0);
+    if (size == 0) {
+        return "";
+    }
+    char *buffer = new char[size];
+    GetEnvironmentVariable(variable, buffer, size);
+    std::string output = buffer;
+    delete[] buffer;
+    return output;
+#else
+    return "";
+#endif
+}
+
 const char *getLayerOption(const char *_option) { return g_configFileObj.getOption(_option); }
 
 // If option is NULL or stdout, return stdout, otherwise try to open option
@@ -155,7 +175,19 @@ ConfigFile::~ConfigFile() {}
 const char *ConfigFile::getOption(const std::string &_option) {
     std::map<std::string, std::string>::const_iterator it;
     if (!m_fileIsParsed) {
-        parseFile("vk_layer_settings.txt");
+        std::string envPath = getEnvironment("VK_LAYER_SETTINGS_PATH");
+
+        // If the path exists use it, else use vk_layer_settings
+        struct stat info;
+        if (stat(envPath.c_str(), &info) == 0) {
+            // If this is a directory, look for vk_layer_settings within the directory
+            if (info.st_mode & S_IFDIR) {
+                envPath += "/vk_layer_settings.txt";
+            }
+            parseFile(envPath.c_str());
+        } else {
+            parseFile("vk_layer_settings.txt");
+        }
     }
 
     if ((it = m_valueMap.find(_option)) == m_valueMap.end())
@@ -166,7 +198,19 @@ const char *ConfigFile::getOption(const std::string &_option) {
 
 void ConfigFile::setOption(const std::string &_option, const std::string &_val) {
     if (!m_fileIsParsed) {
-        parseFile("vk_layer_settings.txt");
+        std::string envPath = getEnvironment("VK_LAYER_SETTINGS_PATH");
+
+        // If the path exists use it, else use vk_layer_settings
+        struct stat info;
+        if (stat(envPath.c_str(), &info) == 0) {
+            // If this is a directory, look for vk_layer_settings within the directory
+            if (info.st_mode & S_IFDIR) {
+                envPath += "/vk_layer_settings.txt";
+            }
+            parseFile(envPath.c_str());
+        } else {
+            parseFile("vk_layer_settings.txt");
+        }
     }
 
     m_valueMap[_option] = _val;