zig/src/libc_installation.zig

699 lines
24 KiB
Zig

const std = @import("std");
const builtin = @import("builtin");
const Target = std.Target;
const fs = std.fs;
const Allocator = std.mem.Allocator;
const build_options = @import("build_options");
const is_darwin = builtin.target.isDarwin();
const is_windows = builtin.target.os.tag == .windows;
const is_haiku = builtin.target.os.tag == .haiku;
const log = std.log.scoped(.libc_installation);
const ZigWindowsSDK = @import("windows_sdk.zig").ZigWindowsSDK;
/// See the render function implementation for documentation of the fields.
pub const LibCInstallation = struct {
include_dir: ?[]const u8 = null,
sys_include_dir: ?[]const u8 = null,
crt_dir: ?[]const u8 = null,
msvc_lib_dir: ?[]const u8 = null,
kernel32_lib_dir: ?[]const u8 = null,
gcc_dir: ?[]const u8 = null,
pub const FindError = error{
OutOfMemory,
FileSystem,
UnableToSpawnCCompiler,
CCompilerExitCode,
CCompilerCrashed,
CCompilerCannotFindHeaders,
LibCRuntimeNotFound,
LibCStdLibHeaderNotFound,
LibCKernel32LibNotFound,
UnsupportedArchitecture,
WindowsSdkNotFound,
ZigIsTheCCompiler,
};
pub fn parse(
allocator: Allocator,
libc_file: []const u8,
target: std.zig.CrossTarget,
) !LibCInstallation {
var self: LibCInstallation = .{};
const fields = std.meta.fields(LibCInstallation);
const FoundKey = struct {
found: bool,
allocated: ?[:0]u8,
};
var found_keys = [1]FoundKey{FoundKey{ .found = false, .allocated = null }} ** fields.len;
errdefer {
self = .{};
for (found_keys) |found_key| {
if (found_key.allocated) |s| allocator.free(s);
}
}
const contents = try std.fs.cwd().readFileAlloc(allocator, libc_file, std.math.maxInt(usize));
defer allocator.free(contents);
var it = std.mem.tokenize(u8, contents, "\n");
while (it.next()) |line| {
if (line.len == 0 or line[0] == '#') continue;
var line_it = std.mem.split(u8, line, "=");
const name = line_it.first();
const value = line_it.rest();
inline for (fields, 0..) |field, i| {
if (std.mem.eql(u8, name, field.name)) {
found_keys[i].found = true;
if (value.len == 0) {
@field(self, field.name) = null;
} else {
found_keys[i].allocated = try allocator.dupeZ(u8, value);
@field(self, field.name) = found_keys[i].allocated;
}
break;
}
}
}
inline for (fields, 0..) |field, i| {
if (!found_keys[i].found) {
log.err("missing field: {s}\n", .{field.name});
return error.ParseError;
}
}
if (self.include_dir == null) {
log.err("include_dir may not be empty\n", .{});
return error.ParseError;
}
if (self.sys_include_dir == null) {
log.err("sys_include_dir may not be empty\n", .{});
return error.ParseError;
}
const os_tag = target.getOsTag();
if (self.crt_dir == null and !target.isDarwin()) {
log.err("crt_dir may not be empty for {s}\n", .{@tagName(os_tag)});
return error.ParseError;
}
const abi = target.getAbi();
if (self.msvc_lib_dir == null and target.isWindows() and abi == .msvc) {
log.err("msvc_lib_dir may not be empty for {s}-{s}\n", .{
@tagName(os_tag),
@tagName(abi),
});
return error.ParseError;
}
if (self.kernel32_lib_dir == null and target.isWindows() and abi == .msvc) {
log.err("kernel32_lib_dir may not be empty for {s}-{s}\n", .{
@tagName(os_tag),
@tagName(abi),
});
return error.ParseError;
}
if (self.gcc_dir == null and os_tag == .haiku) {
log.err("gcc_dir may not be empty for {s}\n", .{@tagName(os_tag)});
return error.ParseError;
}
return self;
}
pub fn render(self: LibCInstallation, out: anytype) !void {
@setEvalBranchQuota(4000);
const include_dir = self.include_dir orelse "";
const sys_include_dir = self.sys_include_dir orelse "";
const crt_dir = self.crt_dir orelse "";
const msvc_lib_dir = self.msvc_lib_dir orelse "";
const kernel32_lib_dir = self.kernel32_lib_dir orelse "";
const gcc_dir = self.gcc_dir orelse "";
try out.print(
\\# The directory that contains `stdlib.h`.
\\# On POSIX-like systems, include directories be found with: `cc -E -Wp,-v -xc /dev/null`
\\include_dir={s}
\\
\\# The system-specific include directory. May be the same as `include_dir`.
\\# On Windows it's the directory that includes `vcruntime.h`.
\\# On POSIX it's the directory that includes `sys/errno.h`.
\\sys_include_dir={s}
\\
\\# The directory that contains `crt1.o` or `crt2.o`.
\\# On POSIX, can be found with `cc -print-file-name=crt1.o`.
\\# Not needed when targeting MacOS.
\\crt_dir={s}
\\
\\# The directory that contains `vcruntime.lib`.
\\# Only needed when targeting MSVC on Windows.
\\msvc_lib_dir={s}
\\
\\# The directory that contains `kernel32.lib`.
\\# Only needed when targeting MSVC on Windows.
\\kernel32_lib_dir={s}
\\
\\# The directory that contains `crtbeginS.o` and `crtendS.o`
\\# Only needed when targeting Haiku.
\\gcc_dir={s}
\\
, .{
include_dir,
sys_include_dir,
crt_dir,
msvc_lib_dir,
kernel32_lib_dir,
gcc_dir,
});
}
pub const FindNativeOptions = struct {
allocator: Allocator,
/// If enabled, will print human-friendly errors to stderr.
verbose: bool = false,
};
/// Finds the default, native libc.
pub fn findNative(args: FindNativeOptions) FindError!LibCInstallation {
var self: LibCInstallation = .{};
if (is_darwin) {
@panic("Darwin is handled separately via std.zig.system.darwin module");
} else if (is_windows) {
if (!build_options.have_llvm)
return error.WindowsSdkNotFound;
var sdk: *ZigWindowsSDK = undefined;
switch (ZigWindowsSDK.find(&sdk)) {
.None => {
defer sdk.free();
try self.findNativeMsvcIncludeDir(args, sdk);
try self.findNativeMsvcLibDir(args, sdk);
try self.findNativeKernel32LibDir(args, sdk);
try self.findNativeIncludeDirWindows(args, sdk);
try self.findNativeCrtDirWindows(args, sdk);
},
.OutOfMemory => return error.OutOfMemory,
.NotFound => return error.WindowsSdkNotFound,
.PathTooLong => return error.WindowsSdkNotFound,
}
} else if (is_haiku) {
try self.findNativeIncludeDirPosix(args);
try self.findNativeCrtBeginDirHaiku(args);
self.crt_dir = try args.allocator.dupeZ(u8, "/system/develop/lib");
} else if (std.process.can_spawn) {
try self.findNativeIncludeDirPosix(args);
switch (builtin.target.os.tag) {
.freebsd, .netbsd, .openbsd, .dragonfly => self.crt_dir = try args.allocator.dupeZ(u8, "/usr/lib"),
.solaris => self.crt_dir = try args.allocator.dupeZ(u8, "/usr/lib/64"),
.linux => try self.findNativeCrtDirPosix(args),
else => {},
}
} else {
return error.LibCRuntimeNotFound;
}
return self;
}
/// Must be the same allocator passed to `parse` or `findNative`.
pub fn deinit(self: *LibCInstallation, allocator: Allocator) void {
const fields = std.meta.fields(LibCInstallation);
inline for (fields) |field| {
if (@field(self, field.name)) |payload| {
allocator.free(payload);
}
}
self.* = undefined;
}
fn findNativeIncludeDirPosix(self: *LibCInstallation, args: FindNativeOptions) FindError!void {
const allocator = args.allocator;
// Detect infinite loops.
var env_map = try std.process.getEnvMap(allocator);
defer env_map.deinit();
const skip_cc_env_var = if (env_map.get(inf_loop_env_key)) |phase| blk: {
if (std.mem.eql(u8, phase, "1")) {
try env_map.put(inf_loop_env_key, "2");
break :blk true;
} else {
return error.ZigIsTheCCompiler;
}
} else blk: {
try env_map.put(inf_loop_env_key, "1");
break :blk false;
};
const dev_null = if (is_windows) "nul" else "/dev/null";
var argv = std.ArrayList([]const u8).init(allocator);
defer argv.deinit();
try appendCcExe(&argv, skip_cc_env_var);
try argv.appendSlice(&.{
"-E",
"-Wp,-v",
"-xc",
dev_null,
});
const exec_res = std.ChildProcess.exec(.{
.allocator = allocator,
.argv = argv.items,
.max_output_bytes = 1024 * 1024,
.env_map = &env_map,
// Some C compilers, such as Clang, are known to rely on argv[0] to find the path
// to their own executable, without even bothering to resolve PATH. This results in the message:
// error: unable to execute command: Executable "" doesn't exist!
// So we use the expandArg0 variant of ChildProcess to give them a helping hand.
.expand_arg0 = .expand,
}) catch |err| switch (err) {
error.OutOfMemory => return error.OutOfMemory,
else => {
printVerboseInvocation(argv.items, null, args.verbose, null);
return error.UnableToSpawnCCompiler;
},
};
defer {
allocator.free(exec_res.stdout);
allocator.free(exec_res.stderr);
}
switch (exec_res.term) {
.Exited => |code| if (code != 0) {
printVerboseInvocation(argv.items, null, args.verbose, exec_res.stderr);
return error.CCompilerExitCode;
},
else => {
printVerboseInvocation(argv.items, null, args.verbose, exec_res.stderr);
return error.CCompilerCrashed;
},
}
var it = std.mem.tokenize(u8, exec_res.stderr, "\n\r");
var search_paths = std.ArrayList([]const u8).init(allocator);
defer search_paths.deinit();
while (it.next()) |line| {
if (line.len != 0 and line[0] == ' ') {
try search_paths.append(line);
}
}
if (search_paths.items.len == 0) {
return error.CCompilerCannotFindHeaders;
}
const include_dir_example_file = if (is_haiku) "posix/stdlib.h" else "stdlib.h";
const sys_include_dir_example_file = if (is_windows)
"sys\\types.h"
else if (is_haiku)
"errno.h"
else
"sys/errno.h";
var path_i: usize = 0;
while (path_i < search_paths.items.len) : (path_i += 1) {
// search in reverse order
const search_path_untrimmed = search_paths.items[search_paths.items.len - path_i - 1];
const search_path = std.mem.trimLeft(u8, search_path_untrimmed, " ");
var search_dir = fs.cwd().openDir(search_path, .{}) catch |err| switch (err) {
error.FileNotFound,
error.NotDir,
error.NoDevice,
=> continue,
else => return error.FileSystem,
};
defer search_dir.close();
if (self.include_dir == null) {
if (search_dir.accessZ(include_dir_example_file, .{})) |_| {
self.include_dir = try allocator.dupeZ(u8, search_path);
} else |err| switch (err) {
error.FileNotFound => {},
else => return error.FileSystem,
}
}
if (self.sys_include_dir == null) {
if (search_dir.accessZ(sys_include_dir_example_file, .{})) |_| {
self.sys_include_dir = try allocator.dupeZ(u8, search_path);
} else |err| switch (err) {
error.FileNotFound => {},
else => return error.FileSystem,
}
}
if (self.include_dir != null and self.sys_include_dir != null) {
// Success.
return;
}
}
return error.LibCStdLibHeaderNotFound;
}
fn findNativeIncludeDirWindows(
self: *LibCInstallation,
args: FindNativeOptions,
sdk: *ZigWindowsSDK,
) FindError!void {
const allocator = args.allocator;
var search_buf: [2]Search = undefined;
const searches = fillSearch(&search_buf, sdk);
var result_buf = std.ArrayList(u8).init(allocator);
defer result_buf.deinit();
for (searches) |search| {
result_buf.shrinkAndFree(0);
try result_buf.writer().print("{s}\\Include\\{s}\\ucrt", .{ search.path, search.version });
var dir = fs.cwd().openDir(result_buf.items, .{}) catch |err| switch (err) {
error.FileNotFound,
error.NotDir,
error.NoDevice,
=> continue,
else => return error.FileSystem,
};
defer dir.close();
dir.accessZ("stdlib.h", .{}) catch |err| switch (err) {
error.FileNotFound => continue,
else => return error.FileSystem,
};
self.include_dir = try result_buf.toOwnedSlice();
return;
}
return error.LibCStdLibHeaderNotFound;
}
fn findNativeCrtDirWindows(
self: *LibCInstallation,
args: FindNativeOptions,
sdk: *ZigWindowsSDK,
) FindError!void {
const allocator = args.allocator;
var search_buf: [2]Search = undefined;
const searches = fillSearch(&search_buf, sdk);
var result_buf = std.ArrayList(u8).init(allocator);
defer result_buf.deinit();
const arch_sub_dir = switch (builtin.target.cpu.arch) {
.x86 => "x86",
.x86_64 => "x64",
.arm, .armeb => "arm",
.aarch64 => "arm64",
else => return error.UnsupportedArchitecture,
};
for (searches) |search| {
result_buf.shrinkAndFree(0);
try result_buf.writer().print("{s}\\Lib\\{s}\\ucrt\\{s}", .{ search.path, search.version, arch_sub_dir });
var dir = fs.cwd().openDir(result_buf.items, .{}) catch |err| switch (err) {
error.FileNotFound,
error.NotDir,
error.NoDevice,
=> continue,
else => return error.FileSystem,
};
defer dir.close();
dir.accessZ("ucrt.lib", .{}) catch |err| switch (err) {
error.FileNotFound => continue,
else => return error.FileSystem,
};
self.crt_dir = try result_buf.toOwnedSlice();
return;
}
return error.LibCRuntimeNotFound;
}
fn findNativeCrtDirPosix(self: *LibCInstallation, args: FindNativeOptions) FindError!void {
self.crt_dir = try ccPrintFileName(.{
.allocator = args.allocator,
.search_basename = "crt1.o",
.want_dirname = .only_dir,
.verbose = args.verbose,
});
}
fn findNativeCrtBeginDirHaiku(self: *LibCInstallation, args: FindNativeOptions) FindError!void {
self.gcc_dir = try ccPrintFileName(.{
.allocator = args.allocator,
.search_basename = "crtbeginS.o",
.want_dirname = .only_dir,
.verbose = args.verbose,
});
}
fn findNativeKernel32LibDir(
self: *LibCInstallation,
args: FindNativeOptions,
sdk: *ZigWindowsSDK,
) FindError!void {
const allocator = args.allocator;
var search_buf: [2]Search = undefined;
const searches = fillSearch(&search_buf, sdk);
var result_buf = std.ArrayList(u8).init(allocator);
defer result_buf.deinit();
const arch_sub_dir = switch (builtin.target.cpu.arch) {
.x86 => "x86",
.x86_64 => "x64",
.arm, .armeb => "arm",
.aarch64 => "arm64",
else => return error.UnsupportedArchitecture,
};
for (searches) |search| {
result_buf.shrinkAndFree(0);
const stream = result_buf.writer();
try stream.print("{s}\\Lib\\{s}\\um\\{s}", .{ search.path, search.version, arch_sub_dir });
var dir = fs.cwd().openDir(result_buf.items, .{}) catch |err| switch (err) {
error.FileNotFound,
error.NotDir,
error.NoDevice,
=> continue,
else => return error.FileSystem,
};
defer dir.close();
dir.accessZ("kernel32.lib", .{}) catch |err| switch (err) {
error.FileNotFound => continue,
else => return error.FileSystem,
};
self.kernel32_lib_dir = try result_buf.toOwnedSlice();
return;
}
return error.LibCKernel32LibNotFound;
}
fn findNativeMsvcIncludeDir(
self: *LibCInstallation,
args: FindNativeOptions,
sdk: *ZigWindowsSDK,
) FindError!void {
const allocator = args.allocator;
const msvc_lib_dir_ptr = sdk.msvc_lib_dir_ptr orelse return error.LibCStdLibHeaderNotFound;
const msvc_lib_dir = msvc_lib_dir_ptr[0..sdk.msvc_lib_dir_len];
const up1 = fs.path.dirname(msvc_lib_dir) orelse return error.LibCStdLibHeaderNotFound;
const up2 = fs.path.dirname(up1) orelse return error.LibCStdLibHeaderNotFound;
const dir_path = try fs.path.join(allocator, &[_][]const u8{ up2, "include" });
errdefer allocator.free(dir_path);
var dir = fs.cwd().openDir(dir_path, .{}) catch |err| switch (err) {
error.FileNotFound,
error.NotDir,
error.NoDevice,
=> return error.LibCStdLibHeaderNotFound,
else => return error.FileSystem,
};
defer dir.close();
dir.accessZ("vcruntime.h", .{}) catch |err| switch (err) {
error.FileNotFound => return error.LibCStdLibHeaderNotFound,
else => return error.FileSystem,
};
self.sys_include_dir = dir_path;
}
fn findNativeMsvcLibDir(
self: *LibCInstallation,
args: FindNativeOptions,
sdk: *ZigWindowsSDK,
) FindError!void {
const allocator = args.allocator;
const msvc_lib_dir_ptr = sdk.msvc_lib_dir_ptr orelse return error.LibCRuntimeNotFound;
self.msvc_lib_dir = try allocator.dupeZ(u8, msvc_lib_dir_ptr[0..sdk.msvc_lib_dir_len]);
}
};
pub const CCPrintFileNameOptions = struct {
allocator: Allocator,
search_basename: []const u8,
want_dirname: enum { full_path, only_dir },
verbose: bool = false,
};
/// caller owns returned memory
fn ccPrintFileName(args: CCPrintFileNameOptions) ![:0]u8 {
const allocator = args.allocator;
// Detect infinite loops.
var env_map = try std.process.getEnvMap(allocator);
defer env_map.deinit();
const skip_cc_env_var = if (env_map.get(inf_loop_env_key)) |phase| blk: {
if (std.mem.eql(u8, phase, "1")) {
try env_map.put(inf_loop_env_key, "2");
break :blk true;
} else {
return error.ZigIsTheCCompiler;
}
} else blk: {
try env_map.put(inf_loop_env_key, "1");
break :blk false;
};
var argv = std.ArrayList([]const u8).init(allocator);
defer argv.deinit();
const arg1 = try std.fmt.allocPrint(allocator, "-print-file-name={s}", .{args.search_basename});
defer allocator.free(arg1);
try appendCcExe(&argv, skip_cc_env_var);
try argv.append(arg1);
const exec_res = std.ChildProcess.exec(.{
.allocator = allocator,
.argv = argv.items,
.max_output_bytes = 1024 * 1024,
.env_map = &env_map,
// Some C compilers, such as Clang, are known to rely on argv[0] to find the path
// to their own executable, without even bothering to resolve PATH. This results in the message:
// error: unable to execute command: Executable "" doesn't exist!
// So we use the expandArg0 variant of ChildProcess to give them a helping hand.
.expand_arg0 = .expand,
}) catch |err| switch (err) {
error.OutOfMemory => return error.OutOfMemory,
else => return error.UnableToSpawnCCompiler,
};
defer {
allocator.free(exec_res.stdout);
allocator.free(exec_res.stderr);
}
switch (exec_res.term) {
.Exited => |code| if (code != 0) {
printVerboseInvocation(argv.items, args.search_basename, args.verbose, exec_res.stderr);
return error.CCompilerExitCode;
},
else => {
printVerboseInvocation(argv.items, args.search_basename, args.verbose, exec_res.stderr);
return error.CCompilerCrashed;
},
}
var it = std.mem.tokenize(u8, exec_res.stdout, "\n\r");
const line = it.next() orelse return error.LibCRuntimeNotFound;
// When this command fails, it returns exit code 0 and duplicates the input file name.
// So we detect failure by checking if the output matches exactly the input.
if (std.mem.eql(u8, line, args.search_basename)) return error.LibCRuntimeNotFound;
switch (args.want_dirname) {
.full_path => return allocator.dupeZ(u8, line),
.only_dir => {
const dirname = fs.path.dirname(line) orelse return error.LibCRuntimeNotFound;
return allocator.dupeZ(u8, dirname);
},
}
}
fn printVerboseInvocation(
argv: []const []const u8,
search_basename: ?[]const u8,
verbose: bool,
stderr: ?[]const u8,
) void {
if (!verbose) return;
if (search_basename) |s| {
std.debug.print("Zig attempted to find the file '{s}' by executing this command:\n", .{s});
} else {
std.debug.print("Zig attempted to find the path to native system libc headers by executing this command:\n", .{});
}
for (argv, 0..) |arg, i| {
if (i != 0) std.debug.print(" ", .{});
std.debug.print("{s}", .{arg});
}
std.debug.print("\n", .{});
if (stderr) |s| {
std.debug.print("Output:\n==========\n{s}\n==========\n", .{s});
}
}
const Search = struct {
path: []const u8,
version: []const u8,
};
fn fillSearch(search_buf: *[2]Search, sdk: *ZigWindowsSDK) []Search {
var search_end: usize = 0;
if (sdk.path10_ptr) |path10_ptr| {
if (sdk.version10_ptr) |version10_ptr| {
search_buf[search_end] = Search{
.path = path10_ptr[0..sdk.path10_len],
.version = version10_ptr[0..sdk.version10_len],
};
search_end += 1;
}
}
if (sdk.path81_ptr) |path81_ptr| {
if (sdk.version81_ptr) |version81_ptr| {
search_buf[search_end] = Search{
.path = path81_ptr[0..sdk.path81_len],
.version = version81_ptr[0..sdk.version81_len],
};
search_end += 1;
}
}
return search_buf[0..search_end];
}
const inf_loop_env_key = "ZIG_IS_DETECTING_LIBC_PATHS";
fn appendCcExe(args: *std.ArrayList([]const u8), skip_cc_env_var: bool) !void {
const default_cc_exe = if (is_windows) "cc.exe" else "cc";
try args.ensureUnusedCapacity(1);
if (skip_cc_env_var) {
args.appendAssumeCapacity(default_cc_exe);
return;
}
const cc_env_var = std.os.getenvZ("CC") orelse {
args.appendAssumeCapacity(default_cc_exe);
return;
};
// Respect space-separated flags to the C compiler.
var it = std.mem.tokenize(u8, cc_env_var, " ");
while (it.next()) |arg| {
try args.append(arg);
}
}