From 818359bfd09e493c8d74b7ace8b91f4d229eab67 Mon Sep 17 00:00:00 2001
From: andy <andy>
Date: Tue, 30 Sep 2008 16:48:36 +0000
Subject: [PATCH] Fixes for bugs shaken out in the recent push: die properly
 for nil indexes in slices.  Fix string conversion issue with bare "+" and
 "-". Fix lexing of exponent expressions such that "1e" is not a number.

---
 simgear/nasal/code.c    | 2 +-
 simgear/nasal/codegen.c | 2 +-
 simgear/nasal/lex.c     | 8 +++++---
 simgear/nasal/string.c  | 4 +---
 4 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/simgear/nasal/code.c b/simgear/nasal/code.c
index 11754b20..cf48dc29 100644
--- a/simgear/nasal/code.c
+++ b/simgear/nasal/code.c
@@ -503,7 +503,7 @@ static int vbound(naContext ctx, naRef v, naRef ir, int end)
 static void evalSlice(naContext ctx, naRef src, naRef dst, naRef idx)
 {
     if(!IS_VEC(src)) ERR(ctx, "cannot slice non-vector");
-    naVec_append(dst, naVec_get(src, vbound(ctx, src, idx, 0)));
+    naVec_append(dst, naVec_get(src, checkVec(ctx, src, idx)));
 }
  
 static void evalSlice2(naContext ctx, naRef src, naRef dst,
diff --git a/simgear/nasal/codegen.c b/simgear/nasal/codegen.c
index 76050031..d1c05ef6 100644
--- a/simgear/nasal/codegen.c
+++ b/simgear/nasal/codegen.c
@@ -560,7 +560,7 @@ static void genAssign(struct Parser* p, struct Token* t)
 
 static void genSlice(struct Parser* p, struct Token* t)
 {
-    if(!t) naParseError(p, "empty slice expression", -1);
+    if(!t || t->type==TOK_EMPTY) naParseError(p, "empty slice expression", -1);
     if(t->type == TOK_COLON) {
         if(LEFT(t))  genExpr(p, LEFT(t));  else emit(p, OP_PUSHNIL);
         if(RIGHT(t)) genExpr(p, RIGHT(t)); else emit(p, OP_PUSHNIL);
diff --git a/simgear/nasal/lex.c b/simgear/nasal/lex.c
index 43253746..d3d525c3 100644
--- a/simgear/nasal/lex.c
+++ b/simgear/nasal/lex.c
@@ -256,20 +256,23 @@ static int lexHexLiteral(struct Parser* p, int index)
     return i;
 }
 
+#define ISNUM(c) ((c) >= '0' && (c) <= '9')
+
 static int lexNumLiteral(struct Parser* p, int index)
 {
     int len = p->len, i = index;
     unsigned char* buf = (unsigned char*)p->buf;
     double d;
 
-    if(i+1<len && buf[i+1] == 'x') return lexHexLiteral(p, index+2);
+    if(buf[0] == '0' && i+1<len && buf[i+1] == 'x')
+        return lexHexLiteral(p, index+2);
 
     while(i<len && buf[i] >= '0' && buf[i] <= '9') i++;
     if(i<len && buf[i] == '.') {
         i++;
         while(i<len && buf[i] >= '0' && buf[i] <= '9') i++;
     }
-    if(i<len && (buf[i] == 'e' || buf[i] == 'E')) {
+    if(i+1<len && (buf[i] == 'e' || buf[i] == 'E') && ISNUM(buf[i+1])) {
         i++;
         if(i<len
            && (buf[i] == '-' || buf[i] == '+')
@@ -333,7 +336,6 @@ static int tryLexemes(struct Parser* p, int index, int* lexemeOut)
     return best;
 }
 
-#define ISNUM(c) ((c) >= '0' && (c) <= '9')
 void naLex(struct Parser* p)
 {
     int i = 0;
diff --git a/simgear/nasal/string.c b/simgear/nasal/string.c
index 65a29526..4855054c 100644
--- a/simgear/nasal/string.c
+++ b/simgear/nasal/string.c
@@ -185,9 +185,7 @@ static int tonum(unsigned char* s, int len, double* result)
     int i=0, fraclen=0;
     double sgn=1, val, frac=0, exp=0;
 
-    // Special case, "." is not a number, even though "1." and ".0" are.
-    if(len == 1 && s[0] == '.')
-        return 0;
+    if(len == 1 && (*s=='.' || *s=='-' || *s=='+')) return 0;
 
     // Strip off the leading negative sign first, so we can correctly
     // parse things like -.xxx which would otherwise confuse