From: Andrew Tridgell <tridge@samba.org>
Date: Wed, 27 Mar 2002 07:12:30 +0000 (+0100)
Subject: explain the mmap code a little
X-Git-Tag: v1.0~30
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=7f1767724fec1a1b1405965df7db56e6632bcf99;p=thirdparty%2Fccache.git

explain the mmap code a little
---

diff --git a/ccache.c b/ccache.c
index 17c620260..05f54694d 100644
--- a/ccache.c
+++ b/ccache.c
@@ -118,6 +118,9 @@ static void stabs_hash(const char *fname)
 		failed();
 	}
 
+	/* we use mmap() to make it easy to handle arbitraryily long
+           lines in preprocessor output. I have seen lines of over
+           100k in length, so this is well worth it */
 	map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
 	if (map == (void *)-1) {
 		cc_log("Failed to mmap %s\n", fname);
@@ -131,6 +134,8 @@ static void stabs_hash(const char *fname)
 		while (l_end < st.st_size && map[l_end] != '\n') {
 			l_end++;
 		}
+		/* skip the hash on any lines that look like compiler line
+		   numbers */
 		if ((l_end - l_start) > 2 &&
 		    map[l_start] == '#' && map[l_start+1] == ' ' && 
 		    isdigit(map[l_start+2])) {
diff --git a/ccache.h b/ccache.h
index cf2b1bb09..3b51d77df 100644
--- a/ccache.h
+++ b/ccache.h
@@ -19,8 +19,6 @@
 #define STATUS_FATAL 4
 #define STATUS_NOCACHE 5
 
-#define MAX_LINE_SIZE 102400
-
 typedef unsigned uint32;
 
 #include "mdfour.h"