dynamically allocates space for strings

diff --git a/parse.lex b/parse.lex
index d89c9c76c83895730f9fb81c53417007d69b5dee..088a7e0e4a9c9c8090c21da088e1985dd6064db1 100644 (file)
--- a/parse.lex
+++ b/parse.lex
@@ -51,11 +51,15 @@ extern YYSTYPE yylval;
 extern int clearaliases;
 int sudolineno = 1;
 static int string_len = 0;
+static int string_size = 0;
 
 static void fill               __P((void));
 static void append             __P((void));
 extern void reset_aliases      __P((void));
 
+/* realloc() to size + COMMANDARGINC to make room for command args */
+#define COMMANDARGINC  256
+
 #ifdef TRACELEXER
 #define LEXTRACE(msg)  fputs(msg, stderr)
 #else
@@ -185,30 +189,43 @@ N                 [0-9][0-9]?[0-9]?
 %%
 static void fill() {
 
-    if (yyleng > MAXCOMMANDLENGTH) {
-       yyerror("command too long, recompile with a larger MAXCOMMANDLENGTH");
-    } else {
-       (void) strcpy(yylval.string, yytext);
-       string_len = yyleng;
-    }
+    string_len = yyleng;       /* length of copied string */
+    string_size = yyleng + 1;  /* leave room for the NULL */
+
+    yylval.string = (char *) malloc(string_size);
+    if (yylval.string == NULL)
+       yyerror("unable to allocate memory");
+    (void) strcpy(yylval.string, yytext);
 }
 
+
 static void append() {
     char *s;
+    int new_len;
+
+    new_len = string_len + yyleng + 1;
 
     /*
-     * Make sure we have enough space...
+     * If we don't have enough space realloc() some more
      */
-    s = yylval.string + string_len;
-    string_len += yyleng + 1;
-    if (string_len > MAXCOMMANDLENGTH) {
-       yyerror("command too long, recompile with a larger MAXCOMMANDLENGTH");
-    } else {
-       *s++ = ' ';
-       (void) strcpy(s, yytext);
+    if (new_len >= string_size) {
+       /* Allocate more space than we need for subsequent args */
+       while (new_len >= (string_size += COMMANDARGINC))
+           ;
+
+       yylval.string = (char *) realloc(yylval.string, string_size);
+       if (yylval.string == NULL )
+           yyerror("unable to allocate memory");
     }
+
+    /* Effeciently append the arg (with a leading space) */
+    s = yylval.string + string_len;
+    *s++ = ' ';
+    (void) strcpy(s, yytext);
+    string_len = new_len;
 }
 
+
 int yywrap()
 {
 #ifdef YY_NEW_FILE