From: Joel Rosdahl <joel@rosdahl.net>
Date: Sun, 5 Sep 2010 19:43:06 +0000 (+0200)
Subject: Don't hash .gch files twice; hash the hash instead
X-Git-Tag: v3.1~16
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=a914a9746268c6108cce66094f070f6038492c98;p=thirdparty%2Fccache.git

Don't hash .gch files twice; hash the hash instead
---

diff --git a/ccache.c b/ccache.c
index 4fe730def..8c9045b6d 100644
--- a/ccache.c
+++ b/ccache.c
@@ -284,12 +284,12 @@ get_path_in_cache(const char *name, const char *suffix)
 static void
 remember_include_file(char *path, size_t path_len, struct mdfour *cpp_hash)
 {
-	struct file_hash *h;
 	struct mdfour fhash;
 	struct stat st;
 	char *source = NULL;
 	size_t size;
 	int result;
+	bool is_pch;
 
 	if (path_len >= 2 && (path[0] == '<' && path[path_len - 1] == '>')) {
 		/* Typically <built-in> or <command-line>. */
@@ -324,12 +324,21 @@ remember_include_file(char *path, size_t path_len, struct mdfour *cpp_hash)
 
 	hash_start(&fhash);
 
-	if (is_precompiled_header(path)) {
-		hash_file2(&fhash, cpp_hash, path);
+	is_pch = is_precompiled_header(path);
+	if (is_pch) {
+		struct file_hash pch_hash;
+		if (!hash_file(&fhash, path)) {
+			goto failure;
+		}
+		hash_result_as_bytes(&fhash, pch_hash.hash);
+		pch_hash.size = fhash.totalN;
+		hash_delimiter(cpp_hash, "pch_hash");
+		hash_buffer(cpp_hash, pch_hash.hash, sizeof(pch_hash.hash));
 	}
-
 	if (enable_direct) {
-		if (!is_precompiled_header(path)) {
+		struct file_hash *h;
+
+		if (!is_pch) { /* else: the file has already been hashed. */
 			if (st.st_size > 0) {
 				if (!read_file(path, st.st_size, &source, &size)) {
 					goto failure;
diff --git a/ccache.h b/ccache.h
index 9977f60d1..eb6b282eb 100644
--- a/ccache.h
+++ b/ccache.h
@@ -92,9 +92,7 @@ void hash_delimiter(struct mdfour *md, const char* type);
 void hash_string(struct mdfour *md, const char *s);
 void hash_int(struct mdfour *md, int x);
 bool hash_fd(struct mdfour *md, int fd);
-bool hash_fd2(struct mdfour *md1, struct mdfour *md2, int fd);
 bool hash_file(struct mdfour *md, const char *fname);
-bool hash_file2(struct mdfour *md1, struct mdfour *md2, const char *fname);
 
 /* ------------------------------------------------------------------------- */
 /* util.c */
diff --git a/hash.c b/hash.c
index 42e0935f1..bcc012ac9 100644
--- a/hash.c
+++ b/hash.c
@@ -95,27 +95,12 @@ hash_int(struct mdfour *md, int x)
  */
 bool
 hash_fd(struct mdfour *md, int fd)
-{
-	return hash_fd2(md, NULL, fd);
-}
-
-/*
- * Add contents of an open file to the hash. Returns true on success, otherwise
- * false.
- */
-bool
-hash_fd2(struct mdfour *md1, struct mdfour *md2, int fd)
 {
 	char buf[16384];
 	ssize_t n;
 
 	while ((n = read(fd, buf, sizeof(buf))) > 0) {
-		if (md1) {
-			hash_buffer(md1, buf, n);
-		}
-		if (md2) {
-			hash_buffer(md2, buf, n);
-		}
+		hash_buffer(md, buf, n);
 	}
 	return n == 0;
 }
@@ -126,16 +111,6 @@ hash_fd2(struct mdfour *md1, struct mdfour *md2, int fd)
  */
 bool
 hash_file(struct mdfour *md, const char *fname)
-{
-	return hash_file2(md, NULL, fname);
-}
-
-/*
- * Add contents of a file to two hash sums. Returns true on success, otherwise
- * false.
- */
-bool
-hash_file2(struct mdfour *md1, struct mdfour *md2, const char *fname)
 {
 	int fd;
 	bool ret;
@@ -145,7 +120,7 @@ hash_file2(struct mdfour *md1, struct mdfour *md2, const char *fname)
 		return false;
 	}
 
-	ret = hash_fd2(md1, md2, fd);
+	ret = hash_fd(md, fd);
 	close(fd);
 	return ret;
 }