Merge branch 'jk/cached-textconv'

* jk/cached-textconv:
  diff: avoid useless filespec population
  diff: cache textconv output
  textconv: refactor calls to run_textconv
  introduce notes-cache interface
  make commit_tree a library function

Documentation/gitattributes.txt

@@ -414,6 +414,26 @@ because it quickly conveys the changes you have made), you
 should generate it separately and send it as a comment _in
 addition to_ the usual binary diff that you might send.
 
+Because text conversion can be slow, especially when doing a
+large number of them with `git log -p`, git provides a mechanism
+to cache the output and use it in future diffs.  To enable
+caching, set the "cachetextconv" variable in your diff driver's
+config. For example:
+
+------------------------
+[diff "jpg"]
+	textconv = exif
+	cachetextconv = true
+------------------------
+
+This will cache the result of running "exif" on each blob
+indefinitely. If you change the textconv config variable for a
+diff driver, git will automatically invalidate the cache entries
+and re-run the textconv filter. If you want to invalidate the
+cache manually (e.g., because your version of "exif" was updated
+and now produces better output), you can remove the cache
+manually with `git update-ref -d refs/notes/textconv/jpg` (where
+"jpg" is the name of the diff driver, as in the example above).
 
 Performing a three-way merge
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Makefile

@@ -486,6 +486,7 @@ LIB_H += log-tree.h
 LIB_H += mailmap.h
 LIB_H += merge-recursive.h
 LIB_H += notes.h
+LIB_H += notes-cache.h
 LIB_H += object.h
 LIB_H += pack.h
 LIB_H += pack-refs.h
@@ -575,6 +576,7 @@ LIB_OBJS += merge-file.o
 LIB_OBJS += merge-recursive.o
 LIB_OBJS += name-hash.o
 LIB_OBJS += notes.o
+LIB_OBJS += notes-cache.o
 LIB_OBJS += object.o
 LIB_OBJS += pack-check.o
 LIB_OBJS += pack-refs.o

builtin.h

@@ -16,9 +16,6 @@ extern const char *help_unknown_cmd(const char *cmd);
 extern void prune_packed_objects(int);
 extern int fmt_merge_msg(int merge_summary, struct strbuf *in,
 	struct strbuf *out);
-extern int commit_tree(const char *msg, unsigned char *tree,
-		struct commit_list *parents, unsigned char *ret,
-		const char *author);
 extern int commit_notes(struct notes_tree *t, const char *msg);
 
 struct notes_rewrite_cfg {

builtin/commit-tree.c

@@ -9,19 +9,6 @@
 #include "builtin.h"
 #include "utf8.h"
 
-/*
- * FIXME! Share the code with "write-tree.c"
- */
-static void check_valid(unsigned char *sha1, enum object_type expect)
-{
-	enum object_type type = sha1_object_info(sha1, NULL);
-	if (type < 0)
-		die("%s is not a valid object", sha1_to_hex(sha1));
-	if (type != expect)
-		die("%s is not a valid '%s' object", sha1_to_hex(sha1),
-		    typename(expect));
-}
-
 static const char commit_tree_usage[] = "git commit-tree <sha1> [-p <sha1>]* < changelog";
 
 static void new_parent(struct commit *parent, struct commit_list **parents_p)
@@ -38,61 +25,6 @@ static void new_parent(struct commit *parent, struct commit_list **parents_p)
 	commit_list_insert(parent, parents_p);
 }
 
-static const char commit_utf8_warn[] =
-"Warning: commit message does not conform to UTF-8.\n"
-"You may want to amend it after fixing the message, or set the config\n"
-"variable i18n.commitencoding to the encoding your project uses.\n";
-
-int commit_tree(const char *msg, unsigned char *tree,
-		struct commit_list *parents, unsigned char *ret,
-		const char *author)
-{
-	int result;
-	int encoding_is_utf8;
-	struct strbuf buffer;
-
-	check_valid(tree, OBJ_TREE);
-
-	/* Not having i18n.commitencoding is the same as having utf-8 */
-	encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
-
-	strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
-	strbuf_addf(&buffer, "tree %s\n", sha1_to_hex(tree));
-
-	/*
-	 * NOTE! This ordering means that the same exact tree merged with a
-	 * different order of parents will be a _different_ changeset even
-	 * if everything else stays the same.
-	 */
-	while (parents) {
-		struct commit_list *next = parents->next;
-		strbuf_addf(&buffer, "parent %s\n",
-			sha1_to_hex(parents->item->object.sha1));
-		free(parents);
-		parents = next;
-	}
-
-	/* Person/date information */
-	if (!author)
-		author = git_author_info(IDENT_ERROR_ON_NO_NAME);
-	strbuf_addf(&buffer, "author %s\n", author);
-	strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_ERROR_ON_NO_NAME));
-	if (!encoding_is_utf8)
-		strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
-	strbuf_addch(&buffer, '\n');
-
-	/* And add the comment */
-	strbuf_addstr(&buffer, msg);
-
-	/* And check the encoding */
-	if (encoding_is_utf8 && !is_utf8(buffer.buf))
-		fprintf(stderr, commit_utf8_warn);
-
-	result = write_sha1_file(buffer.buf, buffer.len, commit_type, ret);
-	strbuf_release(&buffer);
-	return result;
-}
-
 int cmd_commit_tree(int argc, const char **argv, const char *prefix)
 {
 	int i;
@@ -117,7 +49,7 @@ int cmd_commit_tree(int argc, const char **argv, const char *prefix)
 
 		if (get_sha1(b, sha1))
 			die("Not a valid object name %s", b);
-		check_valid(sha1, OBJ_COMMIT);
+		assert_sha1_type(sha1, OBJ_COMMIT);
 		new_parent(lookup_commit(sha1), &parents);
 	}
 

cache.h

@@ -718,6 +718,8 @@ extern int has_loose_object_nonlocal(const unsigned char *sha1);
 
 extern int has_pack_index(const unsigned char *sha1);
 
+extern void assert_sha1_type(const unsigned char *sha1, enum object_type expect);
+
 extern const signed char hexval_table[256];
 static inline unsigned int hexval(unsigned char c)
 {

commit.c

@@ -790,3 +790,58 @@ struct commit_list *reduce_heads(struct commit_list *heads)
 	free(other);
 	return result;
 }
+
+static const char commit_utf8_warn[] =
+"Warning: commit message does not conform to UTF-8.\n"
+"You may want to amend it after fixing the message, or set the config\n"
+"variable i18n.commitencoding to the encoding your project uses.\n";
+
+int commit_tree(const char *msg, unsigned char *tree,
+		struct commit_list *parents, unsigned char *ret,
+		const char *author)
+{
+	int result;
+	int encoding_is_utf8;
+	struct strbuf buffer;
+
+	assert_sha1_type(tree, OBJ_TREE);
+
+	/* Not having i18n.commitencoding is the same as having utf-8 */
+	encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
+
+	strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
+	strbuf_addf(&buffer, "tree %s\n", sha1_to_hex(tree));
+
+	/*
+	 * NOTE! This ordering means that the same exact tree merged with a
+	 * different order of parents will be a _different_ changeset even
+	 * if everything else stays the same.
+	 */
+	while (parents) {
+		struct commit_list *next = parents->next;
+		strbuf_addf(&buffer, "parent %s\n",
+			sha1_to_hex(parents->item->object.sha1));
+		free(parents);
+		parents = next;
+	}
+
+	/* Person/date information */
+	if (!author)
+		author = git_author_info(IDENT_ERROR_ON_NO_NAME);
+	strbuf_addf(&buffer, "author %s\n", author);
+	strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_ERROR_ON_NO_NAME));
+	if (!encoding_is_utf8)
+		strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
+	strbuf_addch(&buffer, '\n');
+
+	/* And add the comment */
+	strbuf_addstr(&buffer, msg);
+
+	/* And check the encoding */
+	if (encoding_is_utf8 && !is_utf8(buffer.buf))
+		fprintf(stderr, commit_utf8_warn);
+
+	result = write_sha1_file(buffer.buf, buffer.len, commit_type, ret);
+	strbuf_release(&buffer);
+	return result;
+}

commit.h

@@ -163,4 +163,8 @@ static inline int single_parent(struct commit *commit)
 
 struct commit_list *reduce_heads(struct commit_list *heads);
 
+extern int commit_tree(const char *msg, unsigned char *tree,
+		struct commit_list *parents, unsigned char *ret,
+		const char *author);
+
 #endif /* COMMIT_H */

diff.c

@@ -44,7 +44,8 @@ static char diff_colors[][COLOR_MAXLEN] = {
 };
 
 static void diff_filespec_load_driver(struct diff_filespec *one);
-static char *run_textconv(const char *, struct diff_filespec *, size_t *);
+static size_t fill_textconv(struct userdiff_driver *driver,
+			    struct diff_filespec *df, char **outbuf);
 
 static int parse_diff_color_slot(const char *var, int ofs)
 {
@@ -466,8 +467,8 @@ static void emit_rewrite_diff(const char *name_a,
 			      const char *name_b,
 			      struct diff_filespec *one,
 			      struct diff_filespec *two,
-			      const char *textconv_one,
-			      const char *textconv_two,
+			      struct userdiff_driver *textconv_one,
+			      struct userdiff_driver *textconv_two,
 			      struct diff_options *o)
 {
 	int lc_a, lc_b;
@@ -478,7 +479,7 @@ static void emit_rewrite_diff(const char *name_a,
 	const char *reset = diff_get_color(color_diff, DIFF_RESET);
 	static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
 	const char *a_prefix, *b_prefix;
-	const char *data_one, *data_two;
+	char *data_one, *data_two;
 	size_t size_one, size_two;
 	struct emit_callback ecbdata;
 
@@ -500,26 +501,8 @@ static void emit_rewrite_diff(const char *name_a,
 	quote_two_c_style(&a_name, a_prefix, name_a, 0);
 	quote_two_c_style(&b_name, b_prefix, name_b, 0);
 
-	diff_populate_filespec(one, 0);
-	diff_populate_filespec(two, 0);
-	if (textconv_one) {
-		data_one = run_textconv(textconv_one, one, &size_one);
-		if (!data_one)
-			die("unable to read files to diff");
-	}
-	else {
-		data_one = one->data;
-		size_one = one->size;
-	}
-	if (textconv_two) {
-		data_two = run_textconv(textconv_two, two, &size_two);
-		if (!data_two)
-			die("unable to read files to diff");
-	}
-	else {
-		data_two = two->data;
-		size_two = two->size;
-	}
+	size_one = fill_textconv(textconv_one, one, &data_one);
+	size_two = fill_textconv(textconv_two, two, &data_two);
 
 	memset(&ecbdata, 0, sizeof(ecbdata));
 	ecbdata.color_diff = color_diff;
@@ -1585,14 +1568,26 @@ void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const
 		options->b_prefix = b;
 }
 
-static const char *get_textconv(struct diff_filespec *one)
+static struct userdiff_driver *get_textconv(struct diff_filespec *one)
 {
 	if (!DIFF_FILE_VALID(one))
 		return NULL;
 	if (!S_ISREG(one->mode))
 		return NULL;
 	diff_filespec_load_driver(one);
-	return one->driver->textconv;
+	if (!one->driver->textconv)
+		return NULL;
+
+	if (one->driver->textconv_want_cache && !one->driver->textconv_cache) {
+		struct notes_cache *c = xmalloc(sizeof(*c));
+		struct strbuf name = STRBUF_INIT;
+
+		strbuf_addf(&name, "textconv/%s", one->driver->name);
+		notes_cache_init(c, name.buf, one->driver->textconv);
+		one->driver->textconv_cache = c;
+	}
+
+	return one->driver;
 }
 
 static void builtin_diff(const char *name_a,
@@ -1609,7 +1604,8 @@ static void builtin_diff(const char *name_a,
 	const char *set = diff_get_color_opt(o, DIFF_METAINFO);
 	const char *reset = diff_get_color_opt(o, DIFF_RESET);
 	const char *a_prefix, *b_prefix;
-	const char *textconv_one = NULL, *textconv_two = NULL;
+	struct userdiff_driver *textconv_one = NULL;
+	struct userdiff_driver *textconv_two = NULL;
 	struct strbuf header = STRBUF_INIT;
 
 	if (DIFF_OPT_TST(o, SUBMODULE_LOG) &&
@@ -1683,12 +1679,11 @@ static void builtin_diff(const char *name_a,
 		}
 	}
 
-	if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
-		die("unable to read files to diff");
-
 	if (!DIFF_OPT_TST(o, TEXT) &&
-	    ( (diff_filespec_is_binary(one) && !textconv_one) ||
-	      (diff_filespec_is_binary(two) && !textconv_two) )) {
+	    ( (!textconv_one && diff_filespec_is_binary(one)) ||
+	      (!textconv_two && diff_filespec_is_binary(two)) )) {
+		if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
+			die("unable to read files to diff");
 		/* Quite common confusing case */
 		if (mf1.size == mf2.size &&
 		    !memcmp(mf1.ptr, mf2.ptr, mf1.size))
@@ -1715,20 +1710,8 @@ static void builtin_diff(const char *name_a,
 			strbuf_reset(&header);
 		}
 
-		if (textconv_one) {
-			size_t size;
-			mf1.ptr = run_textconv(textconv_one, one, &size);
-			if (!mf1.ptr)
-				die("unable to read files to diff");
-			mf1.size = size;
-		}
-		if (textconv_two) {
-			size_t size;
-			mf2.ptr = run_textconv(textconv_two, two, &size);
-			if (!mf2.ptr)
-				die("unable to read files to diff");
-			mf2.size = size;
-		}
+		mf1.size = fill_textconv(textconv_one, one, &mf1.ptr);
+		mf2.size = fill_textconv(textconv_two, two, &mf2.ptr);
 
 		pe = diff_funcname_pattern(one);
 		if (!pe)
@@ -3912,3 +3895,47 @@ static char *run_textconv(const char *pgm, struct diff_filespec *spec,
 
 	return strbuf_detach(&buf, outsize);
 }
+
+static size_t fill_textconv(struct userdiff_driver *driver,
+			    struct diff_filespec *df,
+			    char **outbuf)
+{
+	size_t size;
+
+	if (!driver || !driver->textconv) {
+		if (!DIFF_FILE_VALID(df)) {
+			*outbuf = "";
+			return 0;
+		}
+		if (diff_populate_filespec(df, 0))
+			die("unable to read files to diff");
+		*outbuf = df->data;
+		return df->size;
+	}
+
+	if (driver->textconv_cache) {
+		*outbuf = notes_cache_get(driver->textconv_cache, df->sha1,
+					  &size);
+		if (*outbuf)
+			return size;
+	}
+
+	*outbuf = run_textconv(driver->textconv, df, &size);
+	if (!*outbuf)
+		die("unable to read files to diff");
+
+	if (driver->textconv_cache) {
+		/* ignore errors, as we might be in a readonly repository */
+		notes_cache_put(driver->textconv_cache, df->sha1, *outbuf,
+				size);
+		/*
+		 * we could save up changes and flush them all at the end,
+		 * but we would need an extra call after all diffing is done.
+		 * Since generating a cache entry is the slow path anyway,
+		 * this extra overhead probably isn't a big deal.
+		 */
+		notes_cache_write(driver->textconv_cache);
+	}
+
+	return size;
+}

notes-cache.c

@@ -0,0 +1,94 @@
+#include "cache.h"
+#include "notes-cache.h"
+#include "commit.h"
+#include "refs.h"
+
+static int notes_cache_match_validity(const char *ref, const char *validity)
+{
+	unsigned char sha1[20];
+	struct commit *commit;
+	struct pretty_print_context pretty_ctx;
+	struct strbuf msg = STRBUF_INIT;
+	int ret;
+
+	if (read_ref(ref, sha1) < 0)
+		return 0;
+
+	commit = lookup_commit_reference_gently(sha1, 1);
+	if (!commit)
+		return 0;
+
+	memset(&pretty_ctx, 0, sizeof(pretty_ctx));
+	format_commit_message(commit, "%s", &msg, &pretty_ctx);
+	strbuf_trim(&msg);
+
+	ret = !strcmp(msg.buf, validity);
+	strbuf_release(&msg);
+
+	return ret;
+}
+
+void notes_cache_init(struct notes_cache *c, const char *name,
+		     const char *validity)
+{
+	struct strbuf ref = STRBUF_INIT;
+	int flags = 0;
+
+	memset(c, 0, sizeof(*c));
+	c->validity = xstrdup(validity);
+
+	strbuf_addf(&ref, "refs/notes/%s", name);
+	if (!notes_cache_match_validity(ref.buf, validity))
+		flags = NOTES_INIT_EMPTY;
+	init_notes(&c->tree, ref.buf, combine_notes_overwrite, flags);
+	strbuf_release(&ref);
+}
+
+int notes_cache_write(struct notes_cache *c)
+{
+	unsigned char tree_sha1[20];
+	unsigned char commit_sha1[20];
+
+	if (!c || !c->tree.initialized || !c->tree.ref || !*c->tree.ref)
+		return -1;
+	if (!c->tree.dirty)
+		return 0;
+
+	if (write_notes_tree(&c->tree, tree_sha1))
+		return -1;
+	if (commit_tree(c->validity, tree_sha1, NULL, commit_sha1, NULL) < 0)
+		return -1;
+	if (update_ref("update notes cache", c->tree.ref, commit_sha1, NULL,
+		       0, QUIET_ON_ERR) < 0)
+		return -1;
+
+	return 0;
+}
+
+char *notes_cache_get(struct notes_cache *c, unsigned char key_sha1[20],
+		      size_t *outsize)
+{
+	const unsigned char *value_sha1;
+	enum object_type type;
+	char *value;
+	unsigned long size;
+
+	value_sha1 = get_note(&c->tree, key_sha1);
+	if (!value_sha1)
+		return NULL;
+	value = read_sha1_file(value_sha1, &type, &size);
+
+	*outsize = size;
+	return value;
+}
+
+int notes_cache_put(struct notes_cache *c, unsigned char key_sha1[20],
+		    const char *data, size_t size)
+{
+	unsigned char value_sha1[20];
+
+	if (write_sha1_file(data, size, "blob", value_sha1) < 0)
+		return -1;
+	add_note(&c->tree, key_sha1, value_sha1, NULL);
+	return 0;
+}

notes-cache.h

@@ -0,0 +1,20 @@
+#ifndef NOTES_CACHE_H
+#define NOTES_CACHE_H
+
+#include "notes.h"
+
+struct notes_cache {
+	struct notes_tree tree;
+	char *validity;
+};
+
+void notes_cache_init(struct notes_cache *c, const char *name,
+		     const char *validity);
+int notes_cache_write(struct notes_cache *c);
+
+char *notes_cache_get(struct notes_cache *c, unsigned char sha1[20], size_t
+		      *outsize);
+int notes_cache_put(struct notes_cache *c, unsigned char sha1[20],
+		    const char *data, size_t size);
+
+#endif /* NOTES_CACHE_H */

sha1_file.c

@@ -2516,3 +2516,13 @@ int read_pack_header(int fd, struct pack_header *header)
 		return PH_ERROR_PROTOCOL;
 	return 0;
 }
+
+void assert_sha1_type(const unsigned char *sha1, enum object_type expect)
+{
+	enum object_type type = sha1_object_info(sha1, NULL);
+	if (type < 0)
+		die("%s is not a valid object", sha1_to_hex(sha1));
+	if (type != expect)
+		die("%s is not a valid '%s' object", sha1_to_hex(sha1),
+		    typename(expect));
+}

t/t4042-diff-textconv-caching.sh

@@ -0,0 +1,109 @@
+#!/bin/sh
+
+test_description='test textconv caching'
+. ./test-lib.sh
+
+cat >helper <<'EOF'
+#!/bin/sh
+sed 's/^/converted: /' "$@" >helper.out
+cat helper.out
+EOF
+chmod +x helper
+
+test_expect_success 'setup' '
+	echo foo content 1 >foo.bin &&
+	echo bar content 1 >bar.bin &&
+	git add . &&
+	git commit -m one &&
+	echo foo content 2 >foo.bin &&
+	echo bar content 2 >bar.bin &&
+	git commit -a -m two &&
+	echo "*.bin diff=magic" >.gitattributes &&
+	git config diff.magic.textconv ./helper &&
+	git config diff.magic.cachetextconv true
+'
+
+cat >expect <<EOF
+diff --git a/bar.bin b/bar.bin
+index fcf9166..28283d5 100644
+--- a/bar.bin
++++ b/bar.bin
+@@ -1 +1 @@
+-converted: bar content 1
++converted: bar content 2
+diff --git a/foo.bin b/foo.bin
+index d5b9fe3..1345db2 100644
+--- a/foo.bin
++++ b/foo.bin
+@@ -1 +1 @@
+-converted: foo content 1
++converted: foo content 2
+EOF
+
+test_expect_success 'first textconv works' '
+	git diff HEAD^ HEAD >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'cached textconv produces same output' '
+	git diff HEAD^ HEAD >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'cached textconv does not run helper' '
+	rm -f helper.out &&
+	git diff HEAD^ HEAD >actual &&
+	test_cmp expect actual &&
+	! test -r helper.out
+'
+
+cat >expect <<EOF
+diff --git a/bar.bin b/bar.bin
+index fcf9166..28283d5 100644
+--- a/bar.bin
++++ b/bar.bin
+@@ -1,2 +1,2 @@
+ converted: other
+-converted: bar content 1
++converted: bar content 2
+diff --git a/foo.bin b/foo.bin
+index d5b9fe3..1345db2 100644
+--- a/foo.bin
++++ b/foo.bin
+@@ -1,2 +1,2 @@
+ converted: other
+-converted: foo content 1
++converted: foo content 2
+EOF
+test_expect_success 'changing textconv invalidates cache' '
+	echo other >other &&
+	git config diff.magic.textconv "./helper other" &&
+	git diff HEAD^ HEAD >actual &&
+	test_cmp expect actual
+'
+
+cat >expect <<EOF
+diff --git a/bar.bin b/bar.bin
+index fcf9166..28283d5 100644
+--- a/bar.bin
++++ b/bar.bin
+@@ -1,2 +1,2 @@
+ converted: other
+-converted: bar content 1
++converted: bar content 2
+diff --git a/foo.bin b/foo.bin
+index d5b9fe3..1345db2 100644
+--- a/foo.bin
++++ b/foo.bin
+@@ -1 +1 @@
+-converted: foo content 1
++converted: foo content 2
+EOF
+test_expect_success 'switching diff driver produces correct results' '
+	git config diff.moremagic.textconv ./helper &&
+	echo foo.bin diff=moremagic >>.gitattributes &&
+	git diff HEAD^ HEAD >actual &&
+	test_cmp expect actual
+'
+
+test_done

userdiff.c

@@ -1,3 +1,4 @@
+#include "cache.h"
 #include "userdiff.h"
 #include "cache.h"
 #include "attr.h"
@@ -167,6 +168,12 @@ static int parse_tristate(int *b, const char *k, const char *v)
 	return 1;
 }
 
+static int parse_bool(int *b, const char *k, const char *v)
+{
+	*b = git_config_bool(k, v);
+	return 1;
+}
+
 int userdiff_config(const char *k, const char *v)
 {
 	struct userdiff_driver *drv;
@@ -181,6 +188,8 @@ int userdiff_config(const char *k, const char *v)
 		return parse_string(&drv->external, k, v);
 	if ((drv = parse_driver(k, v, "textconv")))
 		return parse_string(&drv->textconv, k, v);
+	if ((drv = parse_driver(k, v, "cachetextconv")))
+		return parse_bool(&drv->textconv_want_cache, k, v);
 	if ((drv = parse_driver(k, v, "wordregex")))
 		return parse_string(&drv->word_regex, k, v);
 

userdiff.h

@@ -1,6 +1,8 @@
 #ifndef USERDIFF_H
 #define USERDIFF_H
 
+#include "notes-cache.h"
+
 struct userdiff_funcname {
 	const char *pattern;
 	int cflags;
@@ -13,6 +15,8 @@ struct userdiff_driver {
 	struct userdiff_funcname funcname;
 	const char *word_regex;
 	const char *textconv;
+	struct notes_cache *textconv_cache;
+	int textconv_want_cache;
 };
 
 int userdiff_config(const char *k, const char *v);