Added texture pack headers correctly read in

src/devil1tex.c

@@ -0,0 +1,54 @@
+#include "devil1tex.h"
+#include <stdio.h>
+#include <string.h>
+
+// get texture pack header
+void gettph (struct TexturePack *tp, const char *filedata) {
+// Assume the Texture Pack Header is already allocated memory.
+    if (tp != NULL && filedata != NULL) {
+        memcpy(tp, filedata, sizeof(struct TexturePack));
+    }
+    return;
+}
+
+void printtph (struct TexturePack *tp) {
+    if (tp != NULL) { 
+        printf("id: \t %c %c %c %c \n", tp -> id[3], 
+                                        tp -> id[2], 
+                                        tp -> id[1], 
+                                        tp -> id[0]);
+        printf("batch#: \t %i \n",    tp -> batchNumber);
+        printf("1st batch: \t %i \n", tp -> firstBatchOffset);
+        printf("unknownA: \t %i\n",   tp -> unknownA);
+    }
+    return;
+}
+
+// get texture pack descriptors
+void gettbd (struct TextureBatchDescriptor *tbd,
+               struct TexturePack* tph,
+               const char *filedata,
+               unsigned int filesize) {
+    if (tbd == NULL || tph == NULL || filedata == NULL) {
+        // any of these being null will cause segmentation fault.
+        return;
+    }
+    // do some checks regarding the header
+    if (tph -> firstBatchOffset >= filesize || 
+        tph -> firstBatchOffset <= 0) {
+        return;
+    }
+    unsigned int index = tph -> firstBatchOffset;
+    // Batch Descriptors are structured one after another.
+    // therefore the next one is at
+    // current index + sizeof(TextureBatchDescriptor)
+    unsigned int i = 0;
+    do {
+        index += (sizeof(struct TextureBatchDescriptor) * i);
+        printf("batch descriptor start: %x\n", index);
+        tbd = (struct TextureBatchDescriptor*)(filedata + index);
+        // <do something with the batch descriptor found>
+    } while(i < (tph -> batchNumber));
+    return;
+}
+