From 54529d0e4292156e5ae2cd1b90f98242b15d70ca Mon Sep 17 00:00:00 2001
From: dwarning <dwarning>
Date: Tue, 27 Aug 2013 14:28:59 +0200
Subject: [PATCH] allow cshell $variable substitution with and without $&var

---
 src/frontend/variable.c        | 42 ++++++++++++++++++++++++++++++++--
 src/include/ngspice/cpextern.h |  1 +
 2 files changed, 41 insertions(+), 2 deletions(-)

diff --git a/src/frontend/variable.c b/src/frontend/variable.c
index a960d9708..2c94915c8 100644
--- a/src/frontend/variable.c
+++ b/src/frontend/variable.c
@@ -676,6 +676,41 @@ char cp_dol = '$';
 
 #define VALIDCHARS "$-_<#?@.()[]&"
 
+char *
+span_var_expr(char *t)
+{
+    int parenthesis = 0;
+    int brackets = 0;
+
+    while (*t && (isalphanum(*t) || strchr(VALIDCHARS, *t)))
+        switch (*t++)
+        {
+        case '[':
+            brackets++;
+            break;
+        case '(':
+            parenthesis++;
+            break;
+        case ']':
+            if (brackets <= 0)
+                return t-1;
+            if (--brackets <= 0)
+                return t;
+            break;
+        case ')':
+            if (parenthesis <= 0)
+                return t-1;
+            if (--parenthesis <= 0)
+                return t;
+            break;
+        default:
+            break;
+        }
+
+    return t;
+}
+
+
 wordlist *
 cp_variablesubst(wordlist *wlist)
 {
@@ -694,8 +729,11 @@ cp_variablesubst(wordlist *wlist)
             t++;
             s = buf;
             /* Get s and t past the end of the var name. */
-            while (*t && (isalphanum(*t) || strchr(VALIDCHARS, *t)))
-                *s++ = *t++;
+            {
+                char *end = span_var_expr(t);
+                while (t < end)
+                    *s++ = *t++;
+            }
             *s = '\0';
             nwl = vareval(buf);
             if (i) {
diff --git a/src/include/ngspice/cpextern.h b/src/include/ngspice/cpextern.h
index 2d177e9e3..eee84cc53 100644
--- a/src/include/ngspice/cpextern.h
+++ b/src/include/ngspice/cpextern.h
@@ -167,6 +167,7 @@ extern void cp_remvar(char *varname);
 extern void cp_vset(char *varname, enum cp_types type, void *value);
 extern struct variable *cp_setparse(wordlist *wl);
 extern wordlist *vareval(char *string);
+extern char *span_var_expr(char *t);
 
 /* var2.c */
 extern void cp_vprint(void);