load("@bazel_skylib//lib:selects.bzl", "selects")
load("@bazel_skylib//rules:common_settings.bzl", "int_flag", "string_flag")

### Bazel-ification of platform feature detection performed by ./configure ###

# If "yes", the glibc hooks __libc_calloc, __libc_free, __libc_malloc, etc are available for override
string_flag(
    name = "glibc_overrides_support",
    build_setting_default = "__auto__",
    values = [
        "yes",
        "no",
        "__auto__",
    ],
    visibility = ["//visibility:public"],
)

config_setting(
    name = "has_glibc_overrides",
    flag_values = {":glibc_overrides_support": "yes"},
    visibility = ["//visibility:public"],
)

config_setting(
    name = "no_glibc_overrides",
    flag_values = {":glibc_overrides_support": "no"},
    visibility = ["//visibility:public"],
)

# Whether the target libc has `malloc_size` available for linking
string_flag(
    name = "malloc_size_support",
    build_setting_default = "__auto__",
    values = [
        "yes",
        "no",
        "__auto__",
    ],
    visibility = ["//visibility:public"],
)

config_setting(
    name = "has_malloc_size",
    flag_values = {":malloc_size_support": "yes"},
    visibility = ["//visibility:public"],
)

config_setting(
    name = "no_malloc_size",
    flag_values = {":malloc_size_support": "no"},
    visibility = ["//visibility:public"],
)

# JEMALLOC_USABLE_SIZE_CONST: Whether malloc_usable_size can accepts const, glibc on linux apparently omits it
string_flag(
    name = "usable_size_const",
    build_setting_default = "__auto__",
    make_variable = "JEMALLOC_USABLE_SIZE_CONST",
    values = [
        "",
        "const",
        "__auto__",
    ],
    visibility = ["//visibility:public"],
)

string_flag(
    name = "memalign_support",
    build_setting_default = "__auto__",
    values = [
        "yes",
        "no",
        "__auto__",
    ],
    visibility = ["//visibility:public"],
)

config_setting(
    name = "has_memalign",
    flag_values = {":memalign_support": "yes"},
    visibility = ["//visibility:public"],
)

config_setting(
    name = "no_memalign",
    flag_values = {":memalign_support": "no"},
    visibility = ["//visibility:public"],
)

# LG_HUGEPAGE Base 2 log of system huge page size, can be explicitly set --with-lg-hugepage
# The correct setting depends on the kernel. configure defaults to 21 (2 MiB) when detection fails and
# there is runtime detection to gracefully handle a misconfigure value
int_flag(
    name = "lg_hugepage",
    build_setting_default = 21,
    make_variable = "LG_HUGEPAGE",
    visibility = ["//visibility:public"],
)

# LG_PAGE Base 2 log of system page size, can be explicitly set --with-lg-page
string_flag(
    name = "lg_page",
    build_setting_default = "__auto__",
    make_variable = "LG_PAGE",
    visibility = ["//visibility:public"],
)

# LLG_VADDR Number of significant virtual address bits, can be explicitly set --with-lg-vaddr
# The configure cross compilation fallback is the default. This should be safe for any 64-bit target even if the OS
# doesn't allow it because of runtime checks. However, 32-bit architectures should explicitly declare this
# need to declare
int_flag(
    name = "lg_vaddr",
    build_setting_default = 57,
    make_variable = "LG_VADDR",
    visibility = ["//visibility:public"],
)

string_flag(
    name = "valloc_support",
    build_setting_default = "__auto__",
    values = [
        "yes",
        "no",
        "__auto__",
    ],
    visibility = ["//visibility:public"],
)

config_setting(
    name = "has_valloc",
    flag_values = {":valloc_support": "yes"},
    visibility = ["//visibility:public"],
)

config_setting(
    name = "no_valloc",
    flag_values = {":valloc_support": "no"},
    visibility = ["//visibility:public"],
)

### Convenience settings groups ###

# ARM
selects.config_setting_group(
    name = "aarch",
    match_any = [
        "@platforms//cpu:aarch32",
        "@platforms//cpu:aarch64",
    ],
    visibility = ["//:__subpackages__"],
)

# X86
selects.config_setting_group(
    name = "x86",
    match_any = [
        "@platforms//cpu:x86_32",
        "@platforms//cpu:x86_64",
    ],
    visibility = ["//:__subpackages__"],
)

# BSD systems
selects.config_setting_group(
    name = "bsd",
    match_any = [
        "@platforms//os:freebsd",
        "@platforms//os:ios",
        "@platforms//os:macos",
        "@platforms//os:openbsd",
        "@platforms//os:tvos",
        "@platforms//os:watchos",
    ],
    visibility = ["//:__subpackages__"],
)

# Darwin systems
selects.config_setting_group(
    name = "darwin",
    match_any = [
        "@platforms//os:ios",
        "@platforms//os:macos",
        "@platforms//os:tvos",
        "@platforms//os:watchos",
    ],
    visibility = ["//:__subpackages__"],
)

# GNU systems
selects.config_setting_group(
    name = "gnu",
    match_any = [
        "@platforms//os:android",
        "@platforms//os:linux",
    ],
    visibility = ["//:__subpackages__"],
)

# POSIX systems
selects.config_setting_group(
    name = "posix",
    match_any = [
        "@platforms//os:android",
        "@platforms//os:freebsd",
        "@platforms//os:ios",
        "@platforms//os:linux",
        "@platforms//os:macos",
        "@platforms//os:openbsd",
        "@platforms//os:tvos",
        "@platforms//os:watchos",
    ],
    visibility = ["//:__subpackages__"],
)