[gimp] Minor changes to minimize differences to official version of TinyScheme.

[Kevin Cozens <kcozens src gnome org>]

commit 76155d79df8d497d9a5994029247387e222da9e9
Author: Kevin Cozens <kcozens cvs gnome org>
Date:   Mon Aug 17 19:29:02 2009 -0400

    Minor changes to minimize differences to official version of TinyScheme.
    Fixed potential buffer overflow in readstr_upto().

 plug-ins/script-fu/tinyscheme/scheme.c |   33 ++++++++++++++++---------------
 plug-ins/script-fu/tinyscheme/scheme.h |    2 +-
 2 files changed, 18 insertions(+), 17 deletions(-)
---
diff --git a/plug-ins/script-fu/tinyscheme/scheme.c b/plug-ins/script-fu/tinyscheme/scheme.c
index 8bac854..2c793f7 100644
--- a/plug-ins/script-fu/tinyscheme/scheme.c
+++ b/plug-ins/script-fu/tinyscheme/scheme.c
@@ -1763,14 +1763,15 @@ static char *readstr_upto(scheme *sc, char *delim) {
   char *p = sc->strbuff;
   gunichar c = 0;
   gunichar c_prev = 0;
-  int  len = 0;
+  int len = 0;
 
   do {
     c_prev = c;
     c = inchar(sc);
     len = g_unichar_to_utf8(c, p);
     p += len;
-  } while (c && !is_one_of(delim, c));
+  } while ((p - sc->strbuff < sizeof(sc->strbuff)) &&
+           (c && !is_one_of(delim, c)));
 
   if(p == sc->strbuff+2 && c_prev == '\\')
     *p = '\0';
@@ -2105,12 +2106,12 @@ static void atom2str(scheme *sc, pointer l, int f, char **pp, int *plen) {
                default:
 #if USE_ASCII_NAMES
                     if(c==127) {
-                         snprintf(p,STRBUFFSIZE,"#\\del");
+                         snprintf(p,STRBUFFSIZE, "#\\del");
                          break;
                     } else if(c<32) {
-                         snprintf(p,STRBUFFSIZE,"#\\%s", charnames[c]);
+                         snprintf(p,STRBUFFSIZE, "#\\%s", charnames[c]);
                          break;
-                    }
+                     }
 #else
                     if(c<32) {
                       snprintf(p,STRBUFFSIZE,"#\\x%x",c); break;
@@ -2725,7 +2726,7 @@ static pointer opexe_0(scheme *sc, enum scheme_opcodes op) {
        if(sc->tracing) {
          s_save(sc,OP_REAL_APPLY,sc->args,sc->code);
          sc->print_flag = 1;
-         /*         sc->args=cons(sc,sc->code,sc->args);*/
+         /*  sc->args=cons(sc,sc->code,sc->args);*/
          putstr(sc,"\nApply to: ");
          s_goto(sc,OP_P0LIST);
        }
@@ -2837,7 +2838,7 @@ static pointer opexe_0(scheme *sc, enum scheme_opcodes op) {
 
      case OP_SET0:       /* set! */
           if(is_immutable(car(sc->code)))
-                Error_1(sc,"set!: unable to alter immutable variable", car(sc->code));
+                Error_1(sc,"set!: unable to alter immutable variable",car(sc->code));
           s_save(sc,OP_SET1, sc->NIL, car(sc->code));
           sc->code = cadr(sc->code);
           s_goto(sc,OP_EVAL);
@@ -3661,11 +3662,11 @@ static int is_list(scheme *sc, pointer a) {
     }
 }
 
-int list_length(scheme *sc, pointer a) {
+int list_length(scheme *sc, pointer p) {
     int i=0;
     pointer slow, fast;
 
-    slow = fast = a;
+    slow = fast = p;
     while (1)
     {
         if (fast == sc->NIL)
@@ -4245,13 +4246,13 @@ static pointer opexe_5(scheme *sc, enum scheme_opcodes op) {
      case OP_RDVEC:
           /*sc->code=cons(sc,mk_proc(sc,OP_VECTOR),sc->value);
           s_goto(sc,OP_EVAL); Cannot be quoted*/
-       /*x=cons(sc,mk_proc(sc,OP_VECTOR),sc->value);
-         s_return(sc,x); Cannot be part of pairs*/
-       /*sc->code=mk_proc(sc,OP_VECTOR);
-       sc->args=sc->value;
-       s_goto(sc,OP_APPLY);*/
-       sc->args=sc->value;
-       s_goto(sc,OP_VECTOR);
+          /*x=cons(sc,mk_proc(sc,OP_VECTOR),sc->value);
+          s_return(sc,x); Cannot be part of pairs*/
+          /*sc->code=mk_proc(sc,OP_VECTOR);
+          sc->args=sc->value;
+          s_goto(sc,OP_APPLY);*/
+          sc->args=sc->value;
+          s_goto(sc,OP_VECTOR);
 
      /* ========== printing part ========== */
      case OP_P0LIST:
diff --git a/plug-ins/script-fu/tinyscheme/scheme.h b/plug-ins/script-fu/tinyscheme/scheme.h
index dc665b9..3f05ea8 100644
--- a/plug-ins/script-fu/tinyscheme/scheme.h
+++ b/plug-ins/script-fu/tinyscheme/scheme.h
@@ -202,7 +202,7 @@ struct scheme_interface {
   gunichar (*charvalue)(pointer p);
   int (*is_list)(scheme *sc, pointer p);
   int (*is_vector)(pointer p);
-  int (*list_length)(scheme *sc, pointer a);
+  int (*list_length)(scheme *sc, pointer p);
   long (*vector_length)(pointer vec);
   void (*fill_vector)(pointer vec, pointer elem);
   pointer (*vector_elem)(pointer vec, int ielem);