fix: read user shell from /etc/passwd when SHELL not exported

crates/wake-cli/src/commands/shell.rs

@@ -1,12 +1,55 @@
 use anyhow::{Context, Result};
 use chrono::Utc;
 use portable_pty::{native_pty_system, CommandBuilder, PtySize};
-use std::io::{Read, Write};
+use std::io::{BufRead, BufReader, Read, Write};
 use std::os::unix::net::UnixListener;
 use std::sync::{Arc, Mutex};
 use tokio::sync::mpsc;
 use wake_core::{Config, Database, GitCache, HookMessage, OutputBuffer, SummarizationConfig};
 
+/// Get the user's shell, trying multiple sources:
+/// 1. SHELL environment variable
+/// 2. /etc/passwd entry for current user
+/// 3. Fall back to /bin/sh
+fn get_user_shell() -> String {
+    // Try SHELL env var first
+    if let Ok(shell) = std::env::var("SHELL") {
+        return shell;
+    }
+
+    // Try to read from /etc/passwd
+    if let Some(shell) = get_shell_from_passwd() {
+        return shell;
+    }
+
+    // Final fallback
+    "/bin/sh".to_string()
+}
+
+/// Read the current user's shell from /etc/passwd
+fn get_shell_from_passwd() -> Option<String> {
+    let uid = unsafe { libc::getuid() };
+    let file = std::fs::File::open("/etc/passwd").ok()?;
+    let reader = BufReader::new(file);
+
+    for line in reader.lines().map_while(Result::ok) {
+        // Format: username:password:uid:gid:gecos:home:shell
+        let fields: Vec<&str> = line.split(':').collect();
+        if fields.len() >= 7 {
+            if let Ok(entry_uid) = fields[2].parse::<u32>() {
+                if entry_uid == uid {
+                    let shell = fields[6].trim();
+                    if !shell.is_empty() {
+                        return Some(shell.to_string());
+                    }
+                }
+            }
+        }
+    }
+
+    None
+}
+
 struct PendingCommand {
     id: i64,
     command: String,
@@ -38,8 +81,8 @@ pub async fn run() -> Result<()> {
     // Clean up any stale socket
     let _ = std::fs::remove_file(&socket_path);
 
-    // Get user's shell
-    let shell = std::env::var("SHELL").unwrap_or_else(|_| "/bin/sh".to_string());
+    // Get user's shell (env var -> /etc/passwd -> /bin/sh fallback)
+    let shell = get_user_shell();
 
     // Detect project root
     let cwd = std::env::current_dir().ok();
@@ -397,3 +440,64 @@ impl Drop for RawModeGuard {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_get_shell_from_passwd_returns_valid_shell() {
+        // This test runs as the current user, so it should find a shell
+        let shell = get_shell_from_passwd();
+        assert!(shell.is_some(), "Should find current user's shell in /etc/passwd");
+        let shell = shell.unwrap();
+        assert!(shell.starts_with('/'), "Shell should be an absolute path");
+        assert!(
+            shell.contains("sh") || shell.contains("zsh") || shell.contains("fish"),
+            "Shell should be a known shell type: {}",
+            shell
+        );
+    }
+
+    #[test]
+    fn test_get_user_shell_returns_shell() {
+        let shell = get_user_shell();
+        assert!(shell.starts_with('/'), "Shell should be an absolute path");
+        assert!(!shell.is_empty(), "Shell should not be empty");
+    }
+
+    #[test]
+    fn test_get_user_shell_prefers_env_var() {
+        // Save original
+        let original = std::env::var("SHELL").ok();
+
+        // Set a custom SHELL
+        std::env::set_var("SHELL", "/bin/custom-shell");
+        let shell = get_user_shell();
+        assert_eq!(shell, "/bin/custom-shell");
+
+        // Restore original
+        match original {
+            Some(val) => std::env::set_var("SHELL", val),
+            None => std::env::remove_var("SHELL"),
+        }
+    }
+
+    #[test]
+    fn test_get_user_shell_falls_back_to_passwd() {
+        // Save original
+        let original = std::env::var("SHELL").ok();
+
+        // Remove SHELL env var
+        std::env::remove_var("SHELL");
+
+        let shell = get_user_shell();
+        // Should get shell from passwd, not /bin/sh (unless that's actually the user's shell)
+        assert!(shell.starts_with('/'), "Shell should be an absolute path");
+
+        // Restore original
+        if let Some(val) = original {
+            std::env::set_var("SHELL", val);
+        }
+    }
+}

scripts/repro-issue-10.sh

@@ -0,0 +1,82 @@
+#!/bin/bash
+# Reproduction script for https://github.com/joemckenney/wake/issues/10
+# Issue: No commands recorded on immutable Linux OS (Fedora Atomic)
+#
+# Root cause: SHELL env var is not exported on Fedora, so wake falls back
+# to /bin/sh which doesn't source .bashrc, so hooks never load.
+
+set -e
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+REPO_ROOT="$(dirname "$SCRIPT_DIR")"
+
+# Create Dockerfile
+DOCKERFILE=$(mktemp)
+cat > "$DOCKERFILE" << 'DOCKERFILE_CONTENT'
+FROM fedora:43
+
+# Install utilities
+RUN dnf install -y util-linux-script which && dnf clean all
+
+# Mimic Fedora Atomic home directory structure  
+RUN mkdir -p /var/home/testuser && \
+    rm -rf /home && \
+    ln -s /var/home /home && \
+    useradd -d /var/home/testuser -s /bin/bash testuser && \
+    chown -R testuser:testuser /var/home/testuser
+
+# Install wake binary
+COPY target/release/wake /usr/local/bin/wake
+RUN chmod +x /usr/local/bin/wake
+
+# Set up bashrc with wake hooks  
+USER testuser
+WORKDIR /var/home/testuser
+RUN echo 'eval "$(wake init bash)"' >> ~/.bashrc
+
+CMD ["/bin/bash"]
+DOCKERFILE_CONTENT
+
+echo "=== Building container ==="
+docker build -f "$DOCKERFILE" -t wake-fedora-test "$REPO_ROOT"
+
+echo ""
+echo "=== Test 1: Confirm SHELL is not exported ==="
+docker run --rm wake-fedora-test bash -c '
+  echo "SHELL variable: $SHELL"
+  echo "SHELL in env:   $(printenv SHELL || echo "NOT EXPORTED")"
+'
+
+echo ""
+echo "=== Test 2: Reproduce the issue ==="
+docker run --rm wake-fedora-test script -q -c '
+  wake shell << INNER
+    echo "Running inside wake shell..."
+    echo "Hook defined: \$(type __wake_preexec 2>/dev/null && echo YES || echo NO)"
+    ls /tmp > /dev/null
+    exit
+INNER
+  echo ""
+  echo "Commands recorded:"
+  wake log -c 3
+' /dev/null 2>&1 | strings
+
+echo ""
+echo "=== Test 3: Confirm workaround (export SHELL) ==="
+docker run --rm wake-fedora-test script -q -c '
+  export SHELL  # THE FIX
+  wake shell << INNER
+    echo "Hook defined: \$(type __wake_preexec 2>/dev/null && echo YES || echo NO)"
+    ls /tmp > /dev/null
+    exit
+INNER
+  echo ""
+  echo "Commands recorded:"
+  wake log -c 3
+' /dev/null 2>&1 | strings
+
+# Cleanup
+rm -f "$DOCKERFILE"
+
+echo ""
+echo "=== Done ==="