Mesa (mesa_7_5_branch): mesa: don' t call getenv every time _mesa_error is called

[Keith Whitwell]

Module: Mesa
Branch: mesa_7_5_branch
Commit: 6c9d8a6f24db3c947928d72521d5fd544841366e
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=6c9d8a6f24db3c947928d72521d5fd544841366e

Author: Keith Whitwell <keithw at vmware.com>
Date:   Tue Jul 14 16:23:04 2009 +0100

mesa: don't call getenv every time _mesa_error is called

Buggy apps can generate thousands of mesa_error calls.  Don't need
to keep calling getenv to retreive the same MESA_DEBUG string each
time.

---

 src/mesa/main/imports.c |   25 ++++++++++++++-----------
 1 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/src/mesa/main/imports.c b/src/mesa/main/imports.c
index 3fb6708..b0e7d9d 100644
--- a/src/mesa/main/imports.c
+++ b/src/mesa/main/imports.c
@@ -1081,22 +1081,25 @@ _mesa_problem( const GLcontext *ctx, const char *fmtString, ... )
 void
 _mesa_error( GLcontext *ctx, GLenum error, const char *fmtString, ... )
 {
-   const char *debugEnv;
-   GLboolean debug;
+   static GLint debug = -1;
 
-   debugEnv = _mesa_getenv("MESA_DEBUG");
+   /* Check debug environment variable only once:
+    */
+   if (debug == -1) {
+      const char *debugEnv = _mesa_getenv("MESA_DEBUG");
 
 #ifdef DEBUG
-   if (debugEnv && _mesa_strstr(debugEnv, "silent"))
-      debug = GL_FALSE;
-   else
-      debug = GL_TRUE;
+      if (debugEnv && _mesa_strstr(debugEnv, "silent"))
+         debug = GL_FALSE;
+      else
+         debug = GL_TRUE;
 #else
-   if (debugEnv)
-      debug = GL_TRUE;
-   else
-      debug = GL_FALSE;
+      if (debugEnv)
+         debug = GL_TRUE;
+      else
+         debug = GL_FALSE;
 #endif
+   }
 
    if (debug) {
       va_list args;