Squash commits for public release

userland/utilities/cat/.info.mk

@@ -0,0 +1,5 @@
+APPS += CAT
+
+CAT_NAME = cat
+CAT_LIBS = c
+CAT_INSTALL_PATH = bin/

userland/utilities/cat/BUILD.gn

@@ -0,0 +1,8 @@
+import("//build/userland/TEMPLATE.gni")
+
+xOS_executable("cat") {
+  install_path = "bin/"
+  sources = [ "main.c" ]
+  configs = [ "//build/userland:userland_flags" ]
+  deplibs = [ "libc" ]
+}

userland/utilities/cat/main.c

@@ -0,0 +1,37 @@
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#define BUF_SIZE 512
+char buf[BUF_SIZE];
+
+void cat(int fd)
+{
+    int n = 0;
+    while ((n = read(fd, buf, sizeof(buf))) > 0) {
+        if (fwrite(buf, n, 1, stdout) != n) {
+            exit(1);
+        }
+    }
+}
+
+int main(int argc, char** argv)
+{
+    int fd, i;
+
+    if (argc <= 1) {
+        cat(0);
+        return 0;
+    }
+
+    for (i = 1; i < argc; i++) {
+        if ((fd = open(argv[i], O_RDONLY)) < 0) {
+            printf("cat: cannot open %s\n", argv[i]);
+            return 1;
+        }
+        cat(fd);
+        close(fd);
+    }
+    return 0;
+}