av: avoid driver path truncation

[android-x86/hardware-intel-common-libva.git] / va / va.c

diff --git a/va/va.c b/va/va.c
index 28ebe59..a950c6a 100644 (file)
--- a/va/va.c
+++ b/va/va.c
@@ -349,6 +349,23 @@ static VAStatus va_getDriverName(VADisplay dpy, char **driver_name)
     return pDisplayContext->vaGetDriverName(pDisplayContext, driver_name);
 }
 
+static char *va_getDriverPath(const char *driver_dir, const char *driver_name)
+{
+  int n = snprintf(0, 0, "%s/%s%s", driver_dir, driver_name, DRIVER_EXTENSION);
+  if (n < 0)
+      return NULL;
+  char *driver_path = (char *) malloc(n + 1);
+  if (!driver_path)
+      return NULL;
+  n = snprintf(driver_path, n + 1, "%s/%s%s",
+               driver_dir, driver_name, DRIVER_EXTENSION);
+  if (n < 0) {
+    free(driver_path);
+    return NULL;
+  }
+  return driver_path;
+}
+
 static VAStatus va_openDriver(VADisplay dpy, char *driver_name)
 {
     VADriverContextP ctx = CTX(dpy);
@@ -367,9 +384,7 @@ static VAStatus va_openDriver(VADisplay dpy, char *driver_name)
     driver_dir = strtok_r(search_path, ":", &saveptr);
     while (driver_dir) {
         void *handle = NULL;
-        char *driver_path = (char *) malloc( strlen(driver_dir) +
-                                             strlen(driver_name) +
-                                             strlen(DRIVER_EXTENSION) + 2 );
+        char *driver_path = va_getDriverPath(driver_dir, driver_name);
         if (!driver_path) {
             va_errorMessage(dpy, "%s L%d Out of memory!n",
                             __FUNCTION__, __LINE__);
@@ -377,11 +392,6 @@ static VAStatus va_openDriver(VADisplay dpy, char *driver_name)
             return VA_STATUS_ERROR_ALLOCATION_FAILED;
         }
 
-        strncpy( driver_path, driver_dir, strlen(driver_dir) + 1);
-        strncat( driver_path, "/", strlen("/") );
-        strncat( driver_path, driver_name, strlen(driver_name) );
-        strncat( driver_path, DRIVER_EXTENSION, strlen(DRIVER_EXTENSION) );
-        
         va_infoMessage(dpy, "Trying to open %s\n", driver_path);
 #ifndef ANDROID
         handle = dlopen( driver_path, RTLD_NOW | RTLD_GLOBAL | RTLD_NODELETE );