Caleb J. Gardner
53 lines
1.2 KiB
Zig
53 lines
1.2 KiB
Zig
const std = @import("std");
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const Io = std.Io;
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const Decomp = @import("../decomp.zig");
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const CacheMap = @import("protected_map.zig").ProtectedMap(u64, CachedBlock, decompressBlock);
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const Cache = @This();
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alloc: std.mem.Allocator,
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data: []u8,
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decomp: Decomp.Fn,
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cache: CacheMap,
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pub fn init(alloc: std.mem.Allocator, data: []u8, decomp: Decomp.Fn) Cache {
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return .{
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.alloc = alloc,
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.data = data,
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.decomp = decomp,
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.cache = .init(alloc),
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};
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}
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pub fn deinit(self: *Cache) void {
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self.cache.deinit();
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}
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pub fn get(self: *Cache, io: Io, offset: u64, compressed_size: u32) Error![]u8 {
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const res: *CachedBlock = try self.cache.getOrPut(io, offset, .{ self.alloc, self.data, self.decomp, offset, compressed_size });
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return res.block[0..res.size];
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}
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fn decompressBlock(alloc: std.mem.Allocator, data: []u8, decomp: Decomp.Fn, offset: u64, compressed_size: u32) !CachedBlock {
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const block = data[offset..][0..compressed_size];
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var new_cache: CachedBlock = undefined;
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new_cache.size = @truncate(try decomp(alloc, block, &new_cache.block));
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return new_cache;
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}
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// Types
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pub const Error = CacheMap.Error;
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const CachedBlock = struct {
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block: [1024 * 1024]u8,
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size: u32,
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};
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