From c4192a66174cb1c67840a97ba7bc0a706a2c1e2a Mon Sep 17 00:00:00 2001
From: Robert Hensing <robert@roberthensing.nl>
Date: Fri, 16 Aug 2024 15:27:53 +0200
Subject: [PATCH] Add nix::execvpe

---
 src/libutil/unix/exec.hh      | 13 +++++++++++++
 src/libutil/unix/meson.build  |  1 +
 src/libutil/unix/processes.cc |  7 +++++++
 3 files changed, 21 insertions(+)
 create mode 100644 src/libutil/unix/exec.hh

diff --git a/src/libutil/unix/exec.hh b/src/libutil/unix/exec.hh
new file mode 100644
index 000000000..e6b80889a
--- /dev/null
+++ b/src/libutil/unix/exec.hh
@@ -0,0 +1,13 @@
+#pragma once
+
+namespace nix {
+
+/**
+ * `execvpe` is a GNU extension, so we need to implement it for other POSIX
+ * platforms.
+ *
+ * We use our own implementation unconditionally for consistency.
+ */
+int execvpe(const char * file0, char * const argv[], char * const envp[]);
+
+}
diff --git a/src/libutil/unix/meson.build b/src/libutil/unix/meson.build
index 1c5bf27fb..d36152db9 100644
--- a/src/libutil/unix/meson.build
+++ b/src/libutil/unix/meson.build
@@ -13,6 +13,7 @@ sources += files(
 include_dirs += include_directories('.')
 
 headers += files(
+  'exec.hh',
   'monitor-fd.hh',
   'signals-impl.hh',
 )
diff --git a/src/libutil/unix/processes.cc b/src/libutil/unix/processes.cc
index c5ce74acc..09acba35a 100644
--- a/src/libutil/unix/processes.cc
+++ b/src/libutil/unix/processes.cc
@@ -1,5 +1,6 @@
 #include "current-process.hh"
 #include "environment-variables.hh"
+#include "executable-path.hh"
 #include "signals.hh"
 #include "processes.hh"
 #include "finally.hh"
@@ -419,4 +420,10 @@ bool statusOk(int status)
     return WIFEXITED(status) && WEXITSTATUS(status) == 0;
 }
 
+int execvpe(const char * file0, char * const argv[], char * const envp[])
+{
+    auto file = ExecutablePath::load().findPath(file0).string();
+    return execve(file.c_str(), argv, envp);
+}
+
 }