feat(testing): cat (#17)

Signed-off-by: Marco Casaroli <marco.casaroli@gmail.com>

Author: casaroli

CMakeLists.txt

@@ -147,3 +147,9 @@ ExternalProject_Add(sleep5_return0
   CMAKE_ARGS "-DCMAKE_VERBOSE_MAKEFILE:BOOL=${CMAKE_VERBOSE_MAKEFILE}" "-DWAMR_ROOT:STRING=${WAMR_ROOT}"
   INSTALL_COMMAND cp sleep5_return0.wasm ${CMAKE_CURRENT_BINARY_DIR}/dist
 )
+
+ExternalProject_Add(cat
+  SOURCE_DIR ${CMAKE_CURRENT_LIST_DIR}/testing/cat
+  CMAKE_ARGS "-DCMAKE_VERBOSE_MAKEFILE:BOOL=${CMAKE_VERBOSE_MAKEFILE}" "-DWAMR_ROOT:STRING=${WAMR_ROOT}"
+  INSTALL_COMMAND cp cat.wasm ${CMAKE_CURRENT_BINARY_DIR}/dist
+)

testing/cat/CMakeLists.txt

@@ -0,0 +1,7 @@
+cmake_minimum_required(VERSION 3.20.0)
+
+include(${CMAKE_CURRENT_LIST_DIR}/../../ocre.cmake)
+
+project(cat)
+
+add_executable(cat.wasm main.c)

testing/cat/main.c

@@ -0,0 +1,47 @@
+/*
+ * @copyright Copyright © contributors to Project Ocre,
+ * which has been established as Project Ocre a Series of LF Projects, LLC
+
+ * SPDX-License-Identifier: Apache-2.0
+
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+#define BUF_SIZE 4096
+
+int main(int argc, char *argv[])
+{
+	int use_stderr = 0;
+	int out_fd = STDOUT_FILENO;
+
+	for (int i = 1; i < argc; i++) {
+		if (strcmp(argv[i], "-e") == 0) {
+			use_stderr = 1;
+			out_fd = STDERR_FILENO;
+		}
+	}
+
+	char buf[BUF_SIZE];
+	ssize_t n;
+
+	while ((n = read(STDIN_FILENO, buf, sizeof(buf))) > 0) {
+		ssize_t written = 0;
+		while (written < n) {
+			ssize_t w = write(out_fd, buf + written, n - written);
+			if (w < 0) {
+				return 1;
+			}
+			written += w;
+		}
+	}
+
+	if (n < 0) {
+		return 1;
+	}
+
+	return 0;
+}