Add the

	STRING vmod_std.fileread(STRING filename)
function, which will read the contents of a file, typically
for use in synthetic responses.

Submitted by:	Sanjoy Das


git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@5592 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishtest/tests/m00004.vtc

+# $Id$
+# XXX: filenames should really contain m00004 for disambiguation
+
+test "Test fileread for std VMOD"
+
+shell {
+	echo -n "File One" > "${tmpdir}/file_one"
+	echo -n "File Two" > "${tmpdir}/file_two"
+	echo -n "File Three" > "${tmpdir}/file_three"
+}
+
+server s1 {
+	loop 3 {
+		rxreq
+		txresp -hdr "foo: bar" -bodylen 4
+	}
+} -start
+
+varnish v1 -arg "-pvmod_dir=${topbuild}/lib/libvmod_std/.libs/" \
+	-vcl+backend {
+	import std;
+
+	sub vcl_deliver {
+		if (req.url == "/one") {
+			set resp.http.one = std.fileread("${tmpdir}/file_one");
+		} else if (req.url == "/two") {
+			set resp.http.two = std.fileread("${tmpdir}/file_two");
+		} else if (req.url == "/three") {
+			set resp.http.three = std.fileread("${tmpdir}/file_three");
+		}
+	}
+} -start
+
+client c1 {
+	loop 5 {
+		txreq -url "/one"
+		rxresp
+		expect resp.status == 200
+		expect resp.http.content-length == "4"
+		expect resp.http.foo == "bar"
+		expect resp.http.one == "File One"
+	}
+
+	loop 5 {
+		txreq -url "/two"
+		rxresp
+		expect resp.status == 200
+		expect resp.http.content-length == "4"
+		expect resp.http.foo == "bar"
+		expect resp.http.two == "File Two"
+
+		txreq -url "/three"
+		rxresp
+		expect resp.status == 200
+		expect resp.http.content-length == "4"
+		expect resp.http.foo == "bar"
+		expect resp.http.three == "File Three"
+	}
+}
+
+client c2 {
+	loop 5 {
+		txreq -url "/two"
+		rxresp
+		expect resp.status == 200
+		expect resp.http.content-length == "4"
+		expect resp.http.foo == "bar"
+		expect resp.http.two == "File Two"
+	}
+
+	loop 5 {
+		txreq -url "/one"
+		rxresp
+		expect resp.status == 200
+		expect resp.http.content-length == "4"
+		expect resp.http.foo == "bar"
+		expect resp.http.one == "File One"
+
+		txreq -url "/three"
+		rxresp
+		expect resp.status == 200
+		expect resp.http.content-length == "4"
+		expect resp.http.foo == "bar"
+		expect resp.http.three == "File Three"
+	}
+}
+
+client c3 {
+	loop 5 {
+		txreq -url "/three"
+		rxresp
+		expect resp.status == 200
+		expect resp.http.content-length == "4"
+		expect resp.http.foo == "bar"
+		expect resp.http.three == "File Three"
+	}
+
+	loop 5 {
+		txreq -url "/two"
+		rxresp
+		expect resp.status == 200
+		expect resp.http.content-length == "4"
+		expect resp.http.foo == "bar"
+		expect resp.http.two == "File Two"
+
+		txreq -url "/one"
+		rxresp
+		expect resp.status == 200
+		expect resp.http.content-length == "4"
+		expect resp.http.foo == "bar"
+		expect resp.http.one == "File One"
+	}
+}
+
+client c1 -run
+client c2 -run
+client c3 -run

lib/libvmod_std/Makefile.am

@@ -9,7 +9,8 @@ libvmod_std_la_LDFLAGS = -version-info 1:0:0
 libvmod_std_la_SOURCES = \
 	vcc_if.c \
 	vcc_if.h \
-	vmod_std.c
+	vmod_std.c \
+	vmod_std_fileread.c
 
 vcc_if.c vcc_if.h: $(top_srcdir)/lib/libvmod_std/vmod.py $(top_srcdir)/lib/libvmod_std/vmod.vcc
 	@PYTHON@ $(top_srcdir)/lib/libvmod_std/vmod.py $(top_srcdir)/lib/libvmod_std/vmod.vcc

lib/libvmod_std/vmod.vcc

@@ -33,3 +33,4 @@ Function VOID set_ip_tos(INT)
 Function REAL random(REAL, REAL)
 Function VOID log(STRING_LIST)
 Function VOID syslog(INT, STRING_LIST)
+Function STRING fileread(PRIV_CALL, STRING)

lib/libvmod_std/vmod_std_fileread.c

+/*-
+ * Copyright (c) 2010 Linpro AS
+ * All rights reserved.
+ *
+ * Author: Sanjoy Das <sanjoy@playingwithpointers.com>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * XXX: It might make sense to use just a single global list of all files
+ * XXX: and use the call-private pointer to point to the file instance on
+ * XXX: that list.
+ * XXX: Duplicates in the global list can be avoided by examining the
+ * XXX: dev+inode fields of the stat structure.
+ * XXX: Individual files would need to be refcounted, so they can be
+ * XXX: deleted when no VCL's reference them.
+ *
+ * XXX: We should periodically stat(2) the filename and check if the
+ * XXX: underlying file has been updated.
+ */
+
+#include <fcntl.h>
+#include <pthread.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include "vrt.h"
+#include "../../bin/varnishd/cache.h"
+
+#include "vcc_if.h"
+
+VSLIST_HEAD(cached_file_list, cached_file);
+
+struct cached_file {
+	unsigned	magic;
+#define CACHED_FILE_MAGIC 0xa8e9d87a
+	char		*file_name;
+	char		*contents;
+	time_t		last_modification;
+	off_t		file_sz;
+	VSLIST_ENTRY(cached_file) next;
+};
+
+static void
+free_cached_files(void *file_list)
+{
+	struct cached_file *iter, *tmp;
+	struct cached_file_list *list = file_list;
+	VSLIST_FOREACH_SAFE(iter, list, next, tmp) {
+		CHECK_OBJ(iter, CACHED_FILE_MAGIC);
+		free(iter->file_name);
+		free(iter->contents);
+		FREE_OBJ(iter);
+	}
+	free(file_list);
+}
+
+static pthread_rwlock_t filelist_lock = PTHREAD_RWLOCK_INITIALIZER;
+static int filelist_update = 0;
+
+const char *
+vmod_fileread(struct sess *sp, struct vmod_priv *priv, const char *file_name)
+{
+	struct cached_file *iter = NULL;
+	struct stat buf;
+	struct cached_file_list *list;
+	int fd, my_filelist_update;
+
+	(void)sp;
+
+	AZ(pthread_rwlock_rdlock(&filelist_lock));
+
+	if (priv->free == NULL) {
+		AZ(pthread_rwlock_unlock(&filelist_lock));
+		/*
+		 * Another thread may already have initialized priv
+		 * here, making the repeat check necessary.
+		 */
+		AZ(pthread_rwlock_wrlock(&filelist_lock));
+		if (priv->free == NULL) {
+			priv->free = free_cached_files;
+			priv->priv = malloc(sizeof(struct cached_file_list));
+			AN(priv->priv);
+			list = priv->priv;
+			VSLIST_INIT(list);
+		}
+		AZ(pthread_rwlock_unlock(&filelist_lock));
+		AZ(pthread_rwlock_rdlock(&filelist_lock));
+	} else {
+		list = priv->priv;
+		VSLIST_FOREACH(iter, list, next) {
+			CHECK_OBJ(iter, CACHED_FILE_MAGIC);
+			if (strcmp(iter->file_name, file_name) == 0) {
+				/* This thread was holding a read lock. */
+				AZ(pthread_rwlock_unlock(&filelist_lock));
+				return iter->contents;
+			}
+		}
+	}
+
+	my_filelist_update = filelist_update;
+
+	/* This thread was holding a read lock. */
+	AZ(pthread_rwlock_unlock(&filelist_lock));
+
+	if ((fd = open(file_name, O_RDONLY)) == -1)
+		return "";
+
+	fstat(fd, &buf);
+
+	AZ(pthread_rwlock_wrlock(&filelist_lock));
+
+	if (my_filelist_update != filelist_update) {
+
+		/*
+		 * Small optimization: search through the linked list again
+		 * only if something has been changed.
+		 */
+		VSLIST_FOREACH(iter, list, next) {
+			CHECK_OBJ(iter, CACHED_FILE_MAGIC);
+			if (strcmp(iter->file_name, file_name) == 0) {
+				/* This thread was holding a write lock. */
+				AZ(pthread_rwlock_unlock(&filelist_lock));
+				return iter->contents;
+			}
+		}
+	}
+
+	ALLOC_OBJ(iter, CACHED_FILE_MAGIC);
+	AN(iter);
+
+	iter->file_name = strdup(file_name);
+	iter->last_modification = buf.st_mtime;
+
+	iter->contents = malloc(buf.st_size + 1);
+	AN(iter->contents);
+	iter->file_sz = read(fd, iter->contents, buf.st_size);
+	assert(iter->file_sz == buf.st_size);
+	AZ(close(fd));
+
+	iter->contents[iter->file_sz] = '\0';
+
+	VSLIST_INSERT_HEAD(list, iter, next);
+
+	filelist_update++;
+
+	/* This thread was holding a write lock. */
+	AZ(pthread_rwlock_unlock(&filelist_lock));
+	return iter->contents;
+}