zigenv

A tiny, allocation-minimal .env parser with a single-pass in-place parsing over a mutable buffer.

• Parses the common syntax KEY=VALUE pairs that supports those optional quotes
• Supports comments starting with # and blank lines
• Unescapes possible sequences: \n, \r, \t, \\, \"
• Preserves bytes by slicing into the provided buffer there should be no copies unless unescape is needed (in that case it compacts in-place)

How to use this

const std = @import("std");
const zigenv = @import("src/zigenv.zig");

pub fn main() !void {
    var gpa = std.heap.page_allocator;
    var file = try std.fs.cwd().openFile(".env", .{});
    defer file.close();
    const stat = try file.stat();

    var buf = try gpa.alloc(u8, stat.size);
    defer gpa.free(buf);
    _ = try file.readAll(buf);

    var table = std.StringHashMap([]const u8).init(gpa);
    defer table.deinit();

    try zigenv.parseInPlace(&table, buf, .{});

    if (table.get("DATABASE_URL")) |v| {
        std.debug.print("db={s}\n", .{v});
    }
}

Notes

• Input buffer will be modified in-place (nulls and compaction when unescaping). If you need to keep the original bytes, copy them yourself first.
• Lines longer than u32 length aren't supported. You'll need to adjust types if you need extremely large lines.