inpcom.c, introduce find_back_assignment()

src/frontend/inpcom.c

@@ -436,6 +436,27 @@ find_assignment(const char *str)
 }
 
 
+/*
+ * backward search for an assignment
+ *   fixme, doesn't honour neither " nor ' quotes
+ */
+
+char *
+find_back_assignment(const char *p, const char *start)
+{
+    while (--p >= start) {
+        if (*p != '=')
+            continue;
+        // check for '!=', '<=', '>=', '=='
+        if (p <= start || !strchr("!<=>", p[-1]))
+            return (char *) p;
+        p--;
+    }
+
+    return NULL;
+}
+
+
 /*-------------------------------------------------------------------------
   Read the entire input file and return  a pointer to the first line of
   the linked list of 'card' records in data.  The pointer is stored in

src/include/ngspice/fteext.h

@@ -216,6 +216,8 @@ extern struct line *inp_readall(FILE *fp, char *dir_name, bool comfile, bool int
 extern FILE *inp_pathopen(char *name, char *mode);
 extern char *search_identifier(char *str, const char *identifier, char *str_begin);
 extern char *find_assignment(const char *s);
+extern char *find_back_assignment(const char *s, const char *start);
+
 extern struct line *line_nconc(struct line *head, struct line *rest);
 extern struct line *line_reverse(struct line *head);