Inital commit

common/subproc.h

@@ -0,0 +1,59 @@
+#pragma once
+
+#include <atomic>
+#include <cstdio>
+#include <string>
+#include <vector>
+
+#ifdef LLAMA_SUBPROCESS
+#include <sheredom/subprocess.h>
+#else
+// dummy values to allow compilation when subprocess is disabled
+struct subprocess_s {};
+static constexpr int subprocess_option_no_window = 0;
+static constexpr int subprocess_option_combined_stdout_stderr = 0;
+static constexpr int subprocess_option_inherit_environment = 0;
+static constexpr int subprocess_option_search_user_path = 0;
+#endif
+
+// RAII-style wrapper around https://github.com/sheredom/subprocess.h,
+// exposing method calls instead of free functions operating on subprocess_s.
+struct common_subproc {
+    common_subproc() = default;
+    ~common_subproc();
+
+    common_subproc(const common_subproc &) = delete;
+    common_subproc & operator=(const common_subproc &) = delete;
+
+    // spawn a child process; if env is non-empty it replaces the child's environment
+    // (do not combine with subprocess_option_inherit_environment)
+    bool create(
+            const std::vector<std::string> & args,
+            int options,
+            const std::vector<std::string> & env = {},
+            const char * cwd = nullptr);
+
+    bool alive();
+
+    // true if LLAMA_SUBPROCESS was enabled at build time; when false, create() always fails
+    static bool is_supported();
+
+    FILE * stdin_file();
+    FILE * stdout_file();
+    FILE * stderr_file();
+
+    // close stdin and detach it from the process, so a later join()/destroy() won't double-close it;
+    // use this after writing all input to signal EOF to the child while it's still running
+    void close_stdin();
+
+    void terminate();
+
+    // wait for the process to exit, release the underlying handle and return its exit code
+    int join();
+
+private:
+    subprocess_s proc {};
+    std::atomic<bool> is_created{false};
+
+    bool has_handle() const;
+};