Make it possible to build libhardware.

third_party/hwcplus/src/hardware.c

Index: third_party/hwcplus/src/hardware.c
diff --git a/third_party/hwcplus/src/hardware.c b/third_party/hwcplus/src/hardware.c
index 6713ea0107efa7f0aa0b84dfd7881535cc0b4572..7e94d0ba45a84f266ed3c86d8f66fe39bcd90d31 100644
--- a/third_party/hwcplus/src/hardware.c
+++ b/third_party/hwcplus/src/hardware.c
@@ -18,6 +18,7 @@
 
 #include <cutils/properties.h>
 
+#include <stdlib.h>
 #include <dlfcn.h>
 #include <string.h>
 #include <pthread.h>
@@ -28,12 +29,8 @@
 #include <utils/Log.h>
 
 /** Base path of the hal modules */
-#if defined(__LP64__)
-#define HAL_LIBRARY_PATH1 "/system/lib64/hw"
-#define HAL_LIBRARY_PATH2 "/vendor/lib64/hw"
-#else
-#define HAL_LIBRARY_PATH1 "/system/lib/hw"
-#define HAL_LIBRARY_PATH2 "/vendor/lib/hw"
+#if !defined(DEFAULT_HAL_LIBRARY_PATH)
+#define DEFAULT_HAL_LIBRARY_PATH "/usr/lib/hwcplus"
 #endif
 
 /**
@@ -129,13 +126,10 @@ static int load(const char *id,
 static int hw_module_exists(char *path, size_t path_len, const char *name,
                             const char *subname)
 {
-    snprintf(path, path_len, "%s/%s.%s.so",
-             HAL_LIBRARY_PATH2, name, subname);
-    if (access(path, R_OK) == 0)
-        return 0;
-
-    snprintf(path, path_len, "%s/%s.%s.so",
-             HAL_LIBRARY_PATH1, name, subname);
+    char *base = getenv("HAL_LIBRARY_PATH");

[rjkroege, 2014/04/25 21:28:07]

you could be less intrusive and preserve more of the original code with just the
addition of the code to read from the environment variable? And defaults for
CrOS in a #ifdef?

+    if (!base)
+        base = DEFAULT_HAL_LIBRARY_PATH;
+    snprintf(path, path_len, "%s/%s.%s.so", base, name, subname);
     if (access(path, R_OK) == 0)
         return 0;