v0.3: ELF symbol parsing, sym()/addr()/symbols() globals, addrstr/here prelude helpers

src/target.rs

@@ -11,6 +11,8 @@ use nix::unistd::{execvp, fork, ForkResult, Pid};
 use std::ffi::CString;
 use std::io::IoSliceMut;
 
+use crate::symbols::SymbolTable;
+
 /// Why the target stopped after a step/continue, or that it has exited.
 #[derive(Debug, Clone)]
 pub enum StopReason {
@@ -55,6 +57,9 @@ pub struct Target {
     /// Snapshot of registers from the previous stop. None until at least one
     /// step/cont has happened after spawn.
     prev_regs: Option<libc::user_regs_struct>,
+    /// ELF symbols of the main executable. None if parsing failed (e.g.
+    /// stripped binary, unreadable /proc) — symbol lookups become no-ops.
+    symbols: Option<SymbolTable>,
 }
 
 impl Target {
@@ -102,11 +107,15 @@ impl Target {
                 let status = waitpid(child, None)
                     .map_err(|e| format!("waitpid (initial) failed: {}", e))?;
                 match status {
-                    WaitStatus::Stopped(_, Signal::SIGTRAP) => Ok(Target {
-                        pid: child,
-                        state: State::Stopped(StopReason::Step),
-                        prev_regs: None,
-                    }),
+                    WaitStatus::Stopped(_, Signal::SIGTRAP) => {
+                        let symbols = SymbolTable::from_pid(child.as_raw()).ok();
+                        Ok(Target {
+                            pid: child,
+                            state: State::Stopped(StopReason::Step),
+                            prev_regs: None,
+                            symbols,
+                        })
+                    }
                     WaitStatus::Exited(_, code) => {
                         Err(format!("child exited immediately with code {} (exec failed?)", code))
                     }
@@ -143,6 +152,10 @@ impl Target {
         self.prev_regs
     }
 
+    pub fn symbols(&self) -> Option<&SymbolTable> {
+        self.symbols.as_ref()
+    }
+
     fn wait_for_stop(&mut self) -> Result<StopReason, String> {
         let status = waitpid(self.pid, None).map_err(|e| format!("waitpid: {}", e))?;
         let reason = match status {