MrMonopoly/raylib
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

build.zig: Parse all relevant flags from src/config.h at comptime

Browse Source
This commit is contained in:
Sage Hane 2024-10-20 14:11:07 +09:00
parent d53cf3f6b4
commit aed5306da4
No known key found for this signature in database
1 changed files with 37 additions and 30 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

67
src/build.zig
View File

@ -72,6 +72,36 @@ fn srcDir(b: *std.Build) []const u8 {
return std.fs.path.dirname(src_file) orelse ".";
}
/// A list of all flags from `src/config.h` that one may override
const config_h_flags = outer: {
// Set this value higher if compile errors happen as `src/config.h` gets larger
@setEvalBranchQuota(1 << 20);
const config_h = @embedFile("config.h");
var flags: [std.mem.count(u8, config_h, "\n") + 1][]const u8 = undefined;
var i = 0;
var lines = std.mem.tokenizeScalar(u8, config_h, '\n');
while (lines.next()) |line| {
if (!std.mem.containsAtLeast(u8, line, 1, "SUPPORT")) continue;
if (std.mem.startsWith(u8, line, "//")) continue;
if (std.mem.startsWith(u8, line, "#if")) continue;
var flag = std.mem.trimLeft(u8, line, " \t"); // Trim whitespace
flag = flag["#define ".len - 1 ..]; // Remove #define
flag = std.mem.trimLeft(u8, flag, " \t"); // Trim whitespace
flag = flag[0 .. std.mem.indexOf(u8, flag, " ") orelse continue]; // Flag is only one word, so capture till space
flag = "-D" ++ flag; // Prepend with -D
flags[i] = flag;
i += 1;
}
// Uncomment this to check what flags normally get passed
//@compileLog(flags[0..i].*);
break :outer flags[0..i].*;
};
fn compileRaylib(b: *std.Build, target: std.Build.ResolvedTarget, optimize: std.builtin.OptimizeMode, options: Options) !*std.Build.Step.Compile {
raylib_flags_arr.clearRetainingCapacity();
@ -86,16 +116,6 @@ fn compileRaylib(b: *std.Build, target: std.Build.ResolvedTarget, optimize: std.
"-fno-sanitize=undefined", // https://github.com/raysan5/raylib/issues/3674
});
if (options.config.len > 0) {
// Note: Both this and the commented out code immediately below should behave the same.
// `@embedFile` probably captures the intent better, but has the unfortunate consequence of
// bloating up the size of a binary. The performance of a build system probably isn't vital.
// It should also be possible to get the list of configs needed from `src/config.h` at
// comptime such that this cost can be ignored AND simplify the logic.
const content = @embedFile("config.h");
// Note: Usage of `std.build.pathFromRoot` is disadvised according to its documentation
//const file = b.pathFromRoot(b.pathJoin(&.{ srcDir(b), "config.h" }));
//const content = try std.fs.cwd().readFileAlloc(b.allocator, file, std.math.maxInt(usize));
// Sets a flag indiciating the use of a custom `config.h`
try raylib_flags_arr.append(b.allocator, "-DEXTERNAL_CONFIG_FLAGS");
@ -105,30 +125,17 @@ fn compileRaylib(b: *std.Build, target: std.Build.ResolvedTarget, optimize: std.
// `-xc++` or similar should be used when possible
var config_iter = std.mem.tokenizeScalar(u8, options.config, ' ');
// Append config flags supplied by user to compile flags
// Apply config flags supplied by the user
while (config_iter.next()) |config_flag|
try raylib_flags_arr.append(b.allocator, config_flag);
// Apply all relevant configs from `src/config.h` *except* the user-specified ones
var lines = std.mem.tokenizeScalar(u8, content, '\n');
outer: while (lines.next()) |line| {
config_iter.reset();
if (!std.mem.containsAtLeast(u8, line, 1, "SUPPORT")) continue;
if (std.mem.startsWith(u8, line, "//")) continue;
if (std.mem.startsWith(u8, line, "#if")) continue;
var flag = std.mem.trimLeft(u8, line, " \t"); // Trim whitespace
flag = flag["#define ".len - 1 ..]; // Remove #define
flag = std.mem.trimLeft(u8, flag, " \t"); // Trim whitespace
flag = flag[0 .. std.mem.indexOf(u8, flag, " ") orelse continue]; // Flag is only one word, so capture till space
flag = b.fmt("-D{s}", .{flag}); // Prepend with -D
//
// Note: Currently using a suboptimal `O(m*n)` time algorithm where:
// `m` corresponds roughly to the number of lines in `src/config.h`
// `n` corresponds to the number of user-specified flags
outer: for (config_h_flags) |flag| {
// If a user already specified the flag, skip it
//
// Note: Currently using a suboptimal `O(m*n)` time algorithm where:
// `m` corresponds to the number of lines in `src/config.h`
// `n` corresponds to the number of user-specified flags
while (config_iter.next()) |config_flag| {
// For a user-specified flag to match, it must share the same prefix and have the
// same length or be followed by an equals sign
@ -136,7 +143,7 @@ fn compileRaylib(b: *std.Build, target: std.Build.ResolvedTarget, optimize: std.
if (config_flag.len == flag.len or config_flag[flag.len] == '=') continue :outer;
}
// Append default value from config.h to compile flags
// Otherwise, append default value from config.h to compile flags
try raylib_flags_arr.append(b.allocator, flag);
}
}