+static int fill_textconv_grep(struct userdiff_driver *driver,
+ struct grep_source *gs)
+{
+ struct diff_filespec *df;
+ char *buf;
+ size_t size;
+
+ if (!driver || !driver->textconv)
+ return grep_source_load(gs);
+
+ /*
+ * The textconv interface is intimately tied to diff_filespecs, so we
+ * have to pretend to be one. If we could unify the grep_source
+ * and diff_filespec structs, this mess could just go away.
+ */
+ df = alloc_filespec(gs->path);
+ switch (gs->type) {
+ case GREP_SOURCE_SHA1:
+ fill_filespec(df, gs->identifier, 1, 0100644);
+ break;
+ case GREP_SOURCE_FILE:
+ fill_filespec(df, null_sha1, 0, 0100644);
+ break;
+ default:
+ die("BUG: attempt to textconv something without a path?");
+ }
+
+ /*
+ * fill_textconv is not remotely thread-safe; it may load objects
+ * behind the scenes, and it modifies the global diff tempfile
+ * structure.
+ */
+ grep_read_lock();
+ size = fill_textconv(driver, df, &buf);
+ grep_read_unlock();
+ free_filespec(df);
+
+ /*
+ * The normal fill_textconv usage by the diff machinery would just keep
+ * the textconv'd buf separate from the diff_filespec. But much of the
+ * grep code passes around a grep_source and assumes that its "buf"
+ * pointer is the beginning of the thing we are searching. So let's
+ * install our textconv'd version into the grep_source, taking care not
+ * to leak any existing buffer.
+ */
+ grep_source_clear_data(gs);
+ gs->buf = buf;
+ gs->size = size;
+
+ return 0;
+}
+