1 files changed, 86 insertions, 0 deletions
diff --git a/src/permissions.rs b/src/permissions.rs
new file mode 100644
index 000000000..aeeb7df9a
--- /dev/null
+++ b/src/permissions.rs
@@ -0,0 +1,86 @@
+extern crate atty;
+
+use flags::DenoFlags;
+
+use errors::permission_denied;
+use errors::DenoResult;
+use std::io;
+
+#[derive(Debug, Default, PartialEq)]
+pub struct DenoPermissions {
+  pub allow_write: bool,
+  pub allow_net: bool,
+  pub allow_env: bool,
+}
+
+impl DenoPermissions {
+  pub fn new(flags: &DenoFlags) -> DenoPermissions {
+    DenoPermissions {
+      allow_write: flags.allow_write,
+      allow_env: flags.allow_env,
+      allow_net: flags.allow_net,
+    }
+  }
+
+  pub fn check_write(&mut self, filename: &str) -> DenoResult<()> {
+    if self.allow_write {
+      return Ok(());
+    };
+    // TODO get location (where access occurred)
+    let r = permission_prompt(format!(
+      "Deno requests write access to \"{}\".",
+      filename
+    ));;
+    if r.is_ok() {
+      self.allow_write = true;
+    }
+    r
+  }
+
+  pub fn check_net(&mut self, domain_name: &str) -> DenoResult<()> {
+    if self.allow_net {
+      return Ok(());
+    };
+    // TODO get location (where access occurred)
+    let r = permission_prompt(format!(
+      "Deno requests network access to \"{}\".",
+      domain_name
+    ));
+    if r.is_ok() {
+      self.allow_net = true;
+    }
+    r
+  }
+
+  pub fn check_env(&mut self) -> DenoResult<()> {
+    if self.allow_env {
+      return Ok(());
+    };
+    // TODO get location (where access occurred)
+    let r = permission_prompt(
+      "Deno requests access to environment variables.".to_string(),
+    );
+    if r.is_ok() {
+      self.allow_env = true;
+    }
+    r
+  }
+}
+
+fn permission_prompt(message: String) -> DenoResult<()> {
+  if !atty::is(atty::Stream::Stdin) || !atty::is(atty::Stream::Stderr) {
+    return Err(permission_denied());
+  };
+  // print to stderr so that if deno is > to a file this is still displayed.
+  eprint!("{} Grant? [yN] ", message);
+  let mut input = String::new();
+  let stdin = io::stdin();
+  let _nread = stdin.read_line(&mut input)?;
+  let ch = input.chars().next().unwrap();
+  let is_yes = ch == 'y' || ch == 'Y';
+  if is_yes {
+    Ok(())
+  } else {
+    Err(permission_denied())
+  }
+}