From 5af2b9c554fbcb7420ca0312571ff0afb34a6543 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <icculus@icculus.org>
Date: Tue, 25 Oct 2011 12:01:34 -0400
Subject: [PATCH] Several preshader fixes and static analysis tweaks.

---
 mojoshader_effects.c | 33 ++++++++++++++++++++++-----------
 mojoshader_opengl.c  |  2 +-
 2 files changed, 23 insertions(+), 12 deletions(-)

diff --git a/mojoshader_effects.c b/mojoshader_effects.c
index 346341a8..4cda1bff 100644
--- a/mojoshader_effects.c
+++ b/mojoshader_effects.c
@@ -27,11 +27,11 @@ void MOJOSHADER_runPreshader(const MOJOSHADER_preshader *preshader,
         memset(temps, '\0', sizeof (double) * preshader->temp_count);
     } // if
 
-    double dst[4];
-    double src[3][4];
-    const double *src0 = src[0];
-    const double *src1 = src[1];
-    const double *src2 = src[2];
+    double dst[4] = { 0, 0, 0, 0 };
+    double src[3][4] = { { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 } };
+    const double *src0 = &src[0][0];
+    const double *src1 = &src[1][0];
+    const double *src2 = &src[2][0];
 
     MOJOSHADER_preshaderInstruction *inst = preshader->instructions;
     int instit;
@@ -43,6 +43,9 @@ void MOJOSHADER_runPreshader(const MOJOSHADER_preshader *preshader,
         const int elemsbytes = sizeof (double) * elems;
         const int isscalarop = (inst->opcode >= scalarstart);
 
+        assert(elems >= 0);
+        assert(elems <= 4);
+
         // load up our operands...
         int opiter, elemiter;
         for (opiter = 0; opiter < inst->operand_count-1; opiter++, operand++)
@@ -54,8 +57,9 @@ void MOJOSHADER_runPreshader(const MOJOSHADER_preshader *preshader,
                 case MOJOSHADER_PRESHADEROPERAND_LITERAL:
                 {
                     const double *lit = &preshader->literals[index];
+                    assert((index + elems) <= preshader->literal_count);
                     if (!isscalar)
-                        memcpy(src[opiter], lit, elemsbytes);
+                        memcpy(&src[opiter][0], lit, elemsbytes);
                     else
                     {
                         const double val = *lit;
@@ -88,15 +92,18 @@ void MOJOSHADER_runPreshader(const MOJOSHADER_preshader *preshader,
                     break;
 
                 case MOJOSHADER_PRESHADEROPERAND_TEMP:
-                    if (isscalar)
-                        src[opiter][0] = temps[index];
-                    else
-                        memcpy(src[opiter], temps + index, elemsbytes);
+                    if (temps != NULL)
+                    {
+                        if (isscalar)
+                            src[opiter][0] = temps[index];
+                        else
+                            memcpy(src[opiter], temps + index, elemsbytes);
+                    } // if
                     break;
 
                 default:
                     assert(0 && "unexpected preshader operand type.");
-                    break;
+                    return;
             } // switch
         } // for
 
@@ -170,7 +177,11 @@ void MOJOSHADER_runPreshader(const MOJOSHADER_preshader *preshader,
 
         // Figure out where dst wants to be stored.
         if (operand->type == MOJOSHADER_PRESHADEROPERAND_TEMP)
+        {
+            assert(preshader->temp_count >=
+                    operand->index + (elemsbytes / sizeof (double)));
             memcpy(temps + operand->index, dst, elemsbytes);
+        } // if
         else
         {
             assert(operand->type == MOJOSHADER_PRESHADEROPERAND_OUTPUT);
diff --git a/mojoshader_opengl.c b/mojoshader_opengl.c
index 05363123..036d85ca 100644
--- a/mojoshader_opengl.c
+++ b/mojoshader_opengl.c
@@ -1429,7 +1429,7 @@ static int lookup_uniforms(MOJOSHADER_glProgram *program,
 
         if (largest > 0)
         {
-            const size_t len = largest * sizeof (GLfloat);
+            const size_t len = largest * sizeof (GLfloat) * 4;
             GLfloat *buf = (GLfloat *) Malloc(len);
             if (buf == NULL)
                 return 0;