From: guy <guy>
Date: Fri, 26 Oct 2007 00:47:36 +0000 (+0000)
Subject: Re-initialize the table of used registers, and the current register,
X-Git-Url: https://git.tcpdump.org/libpcap/commitdiff_plain/229956f25fd203e8f69b6d7a72afce219027b89b

Re-initialize the table of used registers, and the current register,
before compiling an expression; pcap_compile() can be called more than
once, and some registers can now be allocated and not freed in the
process of code generation (for example, the register allocated to hold
the length of a radiotap header, which can't be freed until we're
finished generating all the code).
---

diff --git a/gencode.c b/gencode.c
index accbf761..177ff925 100644
--- a/gencode.c
+++ b/gencode.c
@@ -21,7 +21,7 @@
  */
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.221.2.53 2007-09-12 19:17:24 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.221.2.54 2007-10-26 00:47:36 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -134,6 +134,7 @@ bpf_error(const char *fmt, ...)
 
 static void init_linktype(pcap_t *);
 
+static void init_regs(void);
 static int alloc_reg(void);
 static void free_reg(int);
 
@@ -369,6 +370,7 @@ pcap_compile(pcap_t *p, struct bpf_program *program,
 	n_errors = 0;
 	root = NULL;
 	bpf_pcap = p;
+	init_regs();
 	if (setjmp(top_ctx)) {
 		lex_cleanup();
 		freechunks();
@@ -5940,6 +5942,16 @@ gen_arth(code, a0, a1)
 static int regused[BPF_MEMWORDS];
 static int curreg;
 
+/*
+ * Initialize the table of used registers and the current register.
+ */
+static void
+init_regs()
+{
+	curreg = 0;
+	memset(regused, 0, sizeof regused);
+}
+
 /*
  * Return the next free register.
  */