Allow to replace memmove function with custom implementation

stb_textedit.h

@@ -358,7 +358,10 @@ typedef struct
 // included just the "header" portion
 #ifdef STB_TEXTEDIT_IMPLEMENTATION
 
-#include <string.h> // memmove
+#ifndef STBTE_memmove
+#include <string.h>
+#define STBTE_memmove memmove
+#endif
 
 
 /////////////////////////////////////////////////////////////////////////////
@@ -1038,13 +1041,13 @@ static void stb_textedit_discard_undo(StbUndoState *state)
          int n = state->undo_rec[0].insert_length, i;
          // delete n characters from all other records
          state->undo_char_point = state->undo_char_point - (short) n;  // vsnet05
-         memmove(state->undo_char, state->undo_char + n, (size_t) (state->undo_char_point*sizeof(STB_TEXTEDIT_CHARTYPE)));
+         STBTE_memmove(state->undo_char, state->undo_char + n, (size_t) (state->undo_char_point*sizeof(STB_TEXTEDIT_CHARTYPE)));
          for (i=0; i < state->undo_point; ++i)
             if (state->undo_rec[i].char_storage >= 0)
                state->undo_rec[i].char_storage = state->undo_rec[i].char_storage - (short) n; // vsnet05 // @OPTIMIZE: get rid of char_storage and infer it
       }
       --state->undo_point;
-      memmove(state->undo_rec, state->undo_rec+1, (size_t) (state->undo_point*sizeof(state->undo_rec[0])));
+      STBTE_memmove(state->undo_rec, state->undo_rec+1, (size_t) (state->undo_point*sizeof(state->undo_rec[0])));
    }
 }
 
@@ -1062,13 +1065,13 @@ static void stb_textedit_discard_redo(StbUndoState *state)
          int n = state->undo_rec[k].insert_length, i;
          // delete n characters from all other records
          state->redo_char_point = state->redo_char_point + (short) n; // vsnet05
-         memmove(state->undo_char + state->redo_char_point, state->undo_char + state->redo_char_point-n, (size_t) ((STB_TEXTEDIT_UNDOSTATECOUNT - state->redo_char_point)*sizeof(STB_TEXTEDIT_CHARTYPE)));
+         STBTE_memmove(state->undo_char + state->redo_char_point, state->undo_char + state->redo_char_point-n, (size_t) ((STB_TEXTEDIT_UNDOSTATECOUNT - state->redo_char_point)*sizeof(STB_TEXTEDIT_CHARTYPE)));
          for (i=state->redo_point; i < k; ++i)
             if (state->undo_rec[i].char_storage >= 0)
                state->undo_rec[i].char_storage = state->undo_rec[i].char_storage + (short) n; // vsnet05
       }
       ++state->redo_point;
-      memmove(state->undo_rec + state->redo_point-1, state->undo_rec + state->redo_point, (size_t) ((STB_TEXTEDIT_UNDOSTATECOUNT - state->redo_point)*sizeof(state->undo_rec[0])));
+      STBTE_memmove(state->undo_rec + state->redo_point-1, state->undo_rec + state->redo_point, (size_t) ((STB_TEXTEDIT_UNDOSTATECOUNT - state->redo_point)*sizeof(state->undo_rec[0])));
    }
 }