diff --git a/fast-import.c b/fast-import.c
index 2f7baf4..74ff0fd 100644
--- a/fast-import.c
+++ b/fast-import.c
@@ -340,7 +340,7 @@
 
 /* Input stream parsing */
 static whenspec_type whenspec = WHENSPEC_RAW;
-static struct strbuf command_buf;
+static struct strbuf command_buf = STRBUF_INIT;
 static int unread_command_buf;
 static struct recent_command cmd_hist = {&cmd_hist, &cmd_hist, NULL};
 static struct recent_command *cmd_tail = &cmd_hist;
@@ -1638,17 +1638,16 @@
 
 static void *cmd_data (size_t *size)
 {
-	size_t length;
-	char *buffer;
+	struct strbuf buffer;
 
+	strbuf_init(&buffer);
 	if (prefixcmp(command_buf.buf, "data "))
 		die("Expected 'data n' command, found: %s", command_buf.buf);
 
 	if (!prefixcmp(command_buf.buf + 5, "<<")) {
 		char *term = xstrdup(command_buf.buf + 5 + 2);
-		size_t sz = 8192, term_len = command_buf.len - 5 - 2;
-		length = 0;
-		buffer = xmalloc(sz);
+		size_t term_len = command_buf.len - 5 - 2;
+
 		for (;;) {
 			read_line(&command_buf, stdin, '\n');
 			if (command_buf.eof)
@@ -1656,21 +1655,18 @@
 			if (term_len == command_buf.len
 				&& !strcmp(term, command_buf.buf))
 				break;
-			ALLOC_GROW(buffer, length + command_buf.len + 1, sz);
-			memcpy(buffer + length,
-				command_buf.buf,
-				command_buf.len);
-			length += command_buf.len;
-			buffer[length++] = '\n';
+			strbuf_addbuf(&buffer, &command_buf);
+			strbuf_addch(&buffer, '\n');
 		}
 		free(term);
 	}
 	else {
-		size_t n = 0;
+		size_t n = 0, length;
+
 		length = strtoul(command_buf.buf + 5, NULL, 10);
-		buffer = xmalloc(length);
+
 		while (n < length) {
-			size_t s = fread(buffer + n, 1, length - n, stdin);
+			size_t s = strbuf_fread(&buffer, length - n, stdin);
 			if (!s && feof(stdin))
 				die("EOF in data (%lu bytes remaining)",
 					(unsigned long)(length - n));
@@ -1679,8 +1675,8 @@
 	}
 
 	skip_optional_lf();
-	*size = length;
-	return buffer;
+	*size = buffer.len;
+	return strbuf_detach(&buffer);
 }
 
 static int validate_raw_date(const char *src, char *result, int maxlen)