zig/std/buf_map.zig

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const HashMap = @import("hash_map.zig").HashMap;
const mem = @import("mem.zig");
const Allocator = mem.Allocator;
/// BufMap copies keys and values before they go into the map, and
/// frees them when they get removed.
pub const BufMap = struct {
hash_map: BufMapHashMap,
const BufMapHashMap = HashMap([]const u8, []const u8, mem.hash_slice_u8, mem.eql_slice_u8);
pub fn init(allocator: &Allocator) -> BufMap {
var self = BufMap {
.hash_map = BufMapHashMap.init(allocator),
};
return self;
}
pub fn deinit(self: &BufMap) {
var it = self.hash_map.iterator();
while (true) {
const entry = it.next() ?? break;
self.free(entry.key);
self.free(entry.value);
}
self.hash_map.deinit();
}
pub fn set(self: &BufMap, key: []const u8, value: []const u8) -> %void {
if (const entry ?= self.hash_map.get(key)) {
const value_copy = %return self.copy(value);
%defer self.free(value_copy);
%return self.hash_map.put(key, value_copy);
self.free(entry.value);
} else {
const key_copy = %return self.copy(key);
%defer self.free(key_copy);
const value_copy = %return self.copy(value);
%defer self.free(value_copy);
%return self.hash_map.put(key_copy, value_copy);
}
}
pub fn delete(self: &BufMap, key: []const u8) {
const entry = self.hash_map.remove(key) ?? return;
self.free(entry.key);
self.free(entry.value);
}
pub fn count(self: &const BufMap) -> usize {
return self.hash_map.size;
}
pub fn iterator(self: &const BufMap) -> BufMapHashMap.Iterator {
return self.hash_map.iterator();
}
fn free(self: &BufMap, value: []const u8) {
// remove the const
const mut_value = @ptrcast(&u8, value.ptr)[0...value.len];
self.hash_map.allocator.free(mut_value);
}
fn copy(self: &BufMap, value: []const u8) -> %[]const u8 {
const result = %return self.hash_map.allocator.alloc(u8, value.len);
mem.copy(u8, result, value);
return result;
}
};