4 files changed, 12 insertions, 0 deletions
diff --git a/cgit.c b/cgit.c
index 19adadd..ae20257 100644
--- a/cgit.c
+++ b/cgit.c
@@ -206,6 +206,7 @@ static void prepare_context(struct cgit_context *ctx)
 	ctx->page.size = 0;
 	ctx->page.modified = time(NULL);
 	ctx->page.expires = ctx->page.modified;
+	ctx->page.etag = NULL;
 }
 
 struct refmatch {
@@ -431,6 +432,7 @@ static int calc_ttl()
 int main(int argc, const char **argv)
 {
 	const char *cgit_config_env = getenv("CGIT_CONFIG");
+	const char *method = getenv("REQUEST_METHOD");
 	const char *path;
 	char *qry;
 	int err, ttl;
@@ -477,6 +479,8 @@ int main(int argc, const char **argv)
 
 	ttl = calc_ttl();
 	ctx.page.expires += ttl*60;
+	if (method && !strcmp(method, "HEAD"))
+		ctx.cfg.nocache = 1;
 	if (ctx.cfg.nocache)
 		ctx.cfg.cache_size = 0;
 	err = cache_process(ctx.cfg.cache_size, ctx.cfg.cache_root,
diff --git a/cgit.h b/cgit.h
index 00aca4c..07a277a 100644
--- a/cgit.h
+++ b/cgit.h
@@ -180,6 +180,7 @@ struct cgit_page {
 	char *mimetype;
 	char *charset;
 	char *filename;
+	char *etag;
 	char *title;
 	int status;
 	char *statusmsg;
diff --git a/ui-plain.c b/ui-plain.c
index 9a9ae7d..93a3a05 100644
--- a/ui-plain.c
+++ b/ui-plain.c
@@ -37,6 +37,7 @@ static void print_object(const unsigned char *sha1, const char *path)
 		ctx.page.mimetype = "text/plain";
 	ctx.page.filename = fmt("%s", path);
 	ctx.page.size = size;
+	ctx.page.etag = sha1_to_hex(sha1);
 	cgit_print_http_headers(&ctx);
 	html_raw(buf, size);
 	match = 1;
diff --git a/ui-shared.c b/ui-shared.c
index 29036d0..10be3c0 100644
--- a/ui-shared.c
+++ b/ui-shared.c
@@ -467,6 +467,8 @@ void cgit_print_age(time_t t, time_t max_relative, char *format)
 
 void cgit_print_http_headers(struct cgit_context *ctx)
 {
+	const char *method = getenv("REQUEST_METHOD");
+
 	if (ctx->page.status)
 		htmlf("Status: %d %s\n", ctx->page.status, ctx->page.statusmsg);
 	if (ctx->page.mimetype && ctx->page.charset)
@@ -481,7 +483,11 @@ void cgit_print_http_headers(struct cgit_context *ctx)
 		      ctx->page.filename);
 	htmlf("Last-Modified: %s\n", http_date(ctx->page.modified));
 	htmlf("Expires: %s\n", http_date(ctx->page.expires));
+	if (ctx->page.etag)
+		htmlf("ETag: \"%s\"\n", ctx->page.etag);
 	html("\n");
+	if (method && !strcmp(method, "HEAD"))
+		exit(0);
 }
 
 void cgit_print_docstart(struct cgit_context *ctx)