Format Introspection

examples/format_introspection.zig — prints the library version string, format spec version, quality and window-size ranges, and the alphabet sizes used by the encoder and decoder.

Client Code

const std = @import("std");
const brotli = @import("brotli");

pub fn main() void {
    std.debug.print("library version : {s} ({d})\n", .{
        brotli.versionString(), brotli.versionNumber(),
    });
    std.debug.print("format spec     : {s}\n", .{brotli.spec_version});
    std.debug.print("quality range   : {d}..{d} (default {d})\n", .{
        brotli.MIN_QUALITY, brotli.MAX_QUALITY, brotli.DEFAULT_QUALITY,
    });
    std.debug.print("window bits     : {d}..{d} (large: up to {d})\n", .{
        brotli.MIN_WINDOW_BITS, brotli.MAX_WINDOW_BITS,
        brotli.LARGE_MAX_WINDOW_BITS,
    });
    std.debug.print("literal symbols : {d}\n", .{brotli.NUM_LITERAL_SYMBOLS});
    std.debug.print("command symbols : {d}\n", .{brotli.NUM_COMMAND_SYMBOLS});
    std.debug.print("distance shorts : {d}\n", .{brotli.NUM_DISTANCE_SHORT_CODES});
}

Output

library version : 0.0.2 (2)
format spec     : 1.2.0
quality range   : 0..11 (default 11)
window bits     : 10..24 (large: up to 30)
literal symbols : 704
command symbols : 704
distance shorts : 16

Explanation

• versionString() returns the human-readable "0.0.2"; versionNumber() returns the encoded integer 2 (major << 24 | minor << 12 | patch).
• spec_version is the Brotli format specification version this library targets: "1.2.0".
• MIN_QUALITY/MAX_QUALITY bound the quality field of CompressionOptions; DEFAULT_QUALITY is 11 (best ratio).
• LARGE_MAX_WINDOW_BITS (30) is the extended window available when decoding large-window Brotli streams; the encoder caps at 24.

Run it:

zig build run-format_introspection