migrating execpolicy -> execpolicy-legacy and execpolicy2 -> execpolicy (#6956)

codex-rs/execpolicy-legacy/src/sed_command.rs

@@ -0,0 +1,17 @@
+use crate::error::Error;
+use crate::error::Result;
+
+pub fn parse_sed_command(sed_command: &str) -> Result<()> {
+    // For now, we parse only commands like `122,202p`.
+    if let Some(stripped) = sed_command.strip_suffix("p")
+        && let Some((first, rest)) = stripped.split_once(",")
+        && first.parse::<u64>().is_ok()
+        && rest.parse::<u64>().is_ok()
+    {
+        return Ok(());
+    }
+
+    Err(Error::SedCommandNotProvablySafe {
+        command: sed_command.to_string(),
+    })
+}