compat.quickjs-ng.lua

-- compat.quickjs-ng — QuickJS-ng, a small embeddable JavaScript engine.
--
-- Shape A (C-source compat): upstream's library target and nothing else. A
-- consumer writes `#include <quickjs.h>` and links the lib.
--
-- WHAT IS COMPILED. Upstream's `qjs_sources` (CMakeLists.txt:273-278): dtoa.c,
-- libregexp.c, libunicode.c and quickjs.c. quickjs-libc.c is NOT compiled. It
-- is upstream's optional standard library, the `std` / `os` / `bjson` modules
-- (files, environment variables, timers, child processes, signal handlers).
-- Upstream's own library leaves it out by default too: CMake adds it only under
-- QJS_BUILD_LIBC (meson: -Dlibc=true) and otherwise builds it as a separate,
-- uninstalled static library for the qjs and qjsc programs. An embedder that
-- wants the engine without giving scripts access to the host needs it left
-- out. The other .c files at the root are the qjs/qjsc programs, tests and
-- generators.
--
-- ONE PUBLIC HEADER. Without quickjs-libc, upstream installs quickjs.h alone
-- (CMakeLists.txt:557, meson.build:144-146 and 263), but the tarball keeps it
-- at the root beside the engine's private headers, among them list.h, cutils.h
-- and dtoa.h, names generic enough to shadow a consumer's own. So a one-line
-- forwarder through `generated_files` is the only directory on the include
-- path (the compat.libaio pattern). The engine's own TUs include their headers
-- in quote form next to the .c and need no -I.
--
-- FLAGS, each one as upstream's CMake and meson builds set it:
--   -std=gnu11          C11 with GNU extensions (CMakeLists.txt:9-11,
--                       meson.build:6). The -std on this package's compile
--                       line does not follow `c_standard`: "gnu11" there still
--                       gives -std=c11 (the same observation as compat.libaio),
--                       so the dialect arrives through `cflags`, where the
--                       later -std wins.
--   -funsigned-char     CMakeLists.txt:109, meson.build:42, and /J for MSVC
--                       (meson.build:70). x86_64 and aarch64 Linux disagree on
--                       the sign of plain char, and upstream pins it so the
--                       engine behaves the same on both. A consumer does not
--                       need it: quickjs.h only passes char by pointer.
--   -D_GNU_SOURCE       CMakeLists.txt:285 and meson.build:162, on every
--                       platform.
--   -DQUICKJS_NG_BUILD  CMakeLists.txt:46, meson.build:19. quickjs.h reads it
--                       only for quickjs-libc's Windows export macro
--                       (quickjs.h:82), so it has no effect on Linux today; it
--                       is set so the engine's TUs see the macros upstream's
--                       own build gives them.
-- All four go through `cflags`, so they reach this package's C TUs and never a
-- consumer's TU. NDEBUG is not set, as in most descriptors here, so the engine
-- keeps its assertions and its debug-dump code (quickjs.c:84-86); upstream's
-- default build type (Release) would define it.
--
-- LINUX ONLY. Built and tested with llvm 22.1.8 on x86_64-linux-gnu, and in an
-- openkal graph for x86_64-linux-gnu. Upstream supports macOS and Windows, but
-- nothing here has built the package there, so those sections are not declared.
--
-- NO CN MIRROR. The url is upstream's tag archive as a plain string, the
-- fallback docs/cn-mirror.md describes for a contributor without mcpp-res write
-- access. A maintainer can turn it into a GLOBAL/CN table later; the sha256
-- does not change.
--
-- LICENSES. The engine is MIT (LICENSE). libunicode-table.h, which libunicode.c
-- compiles in, is generated from the Unicode data files and carries the
-- Unicode License V3 in its header, so a binary built from this package needs
-- both notices.
package = {
    spec        = "1",
    namespace   = "compat",
    name        = "quickjs-ng",
    description = "QuickJS-ng, a small embeddable JavaScript engine (engine only, without quickjs-libc)",
    licenses    = {"MIT", "Unicode-3.0"},
    repo        = "https://github.com/quickjs-ng/quickjs",
    type        = "package",

    xpm = {
        linux = {
            ["0.17.0"] = {
                url    = "https://github.com/quickjs-ng/quickjs/archive/refs/tags/v0.17.0.tar.gz",
                sha256 = "559bc4c420475e55c7ab4510adbc562f55d7524d75e8e89d79ce4bb02f5687d9",
            },
        },
    },

    mcpp = {
        language     = "c++23",
        import_std   = false,
        c_standard   = "c11",
        include_dirs = { "quickjs-0.17.0/mcpp/include" },
        cflags       = { "-std=gnu11", "-funsigned-char", "-D_GNU_SOURCE", "-DQUICKJS_NG_BUILD" },
        sources      = {
            "*/dtoa.c",
            "*/libregexp.c",
            "*/libunicode.c",
            "*/quickjs.c",
        },
        generated_files = {
            ["quickjs-0.17.0/mcpp/include/quickjs.h"] =
[[
#pragma once
/* compat.quickjs-ng: upstream installs quickjs.h alone, but the release
   tarball keeps it beside the engine's private headers (list.h, cutils.h,
   dtoa.h, ...). This forwarder is the only thing on the include path. */
#include "../../quickjs.h"
]],
        },
        -- Upstream links `m`, the dl library and the thread library PUBLIC
        -- (CMakeLists.txt:291-311). A consumer with no C++ in it is linked by
        -- the C driver, which adds no libm, and quickjs.c's Math functions then
        -- fail to link. libdl is left out: only quickjs-libc.c calls dlopen.
        linux        = { ldflags = { "-lm", "-lpthread" } },
        targets      = { ["quickjs-ng"] = { kind = "lib" } },
        deps         = { },
    },
}