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-rw-r--r--stdlib/tables.c798
1 files changed, 0 insertions, 798 deletions
diff --git a/stdlib/tables.c b/stdlib/tables.c
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--- a/stdlib/tables.c
+++ /dev/null
@@ -1,798 +0,0 @@
-// table.c - C Hash table implementation
-// Copyright 2024 Bruce Hill
-// Provided under the MIT license with the Commons Clause
-// See included LICENSE for details.
-
-// Hash table (aka Dictionary) Implementation
-// Hash keys and values are stored *by value*
-// The hash insertion/lookup implementation is based on Lua's tables,
-// which use a chained scatter with Brent's variation.
-
-#include <assert.h>
-#include <gc.h>
-#include <stdarg.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/param.h>
-
-#include "arrays.h"
-#include "c_strings.h"
-#include "datatypes.h"
-#include "memory.h"
-#include "metamethods.h"
-#include "pointers.h"
-#include "siphash.h"
-#include "tables.h"
-#include "text.h"
-#include "types.h"
-#include "util.h"
-
-// #define DEBUG_TABLES
-
-#ifdef DEBUG_TABLES
-#define hdebug(fmt, ...) printf("\x1b[2m" fmt "\x1b[m" __VA_OPT__(,) __VA_ARGS__)
-#else
-#define hdebug(...) (void)0
-#endif
-
-// Helper accessors for type functions/values:
-#define HASH_KEY(t, k) (generic_hash((k), type->TableInfo.key) % ((t).bucket_info->count))
-#define EQUAL_KEYS(x, y) (generic_equal((x), (y), type->TableInfo.key))
-#define END_OF_CHAIN UINT32_MAX
-
-#define GET_ENTRY(t, i) ((t).entries.data + (t).entries.stride*(i))
-
-static TypeInfo_t MemoryPointer = {
- .size=sizeof(void*),
- .align=__alignof__(void*),
- .tag=PointerInfo,
- .PointerInfo={
- .sigil="@",
- .pointed=&Memory$info,
- },
- .metamethods=Pointer$metamethods,
-};
-
-const TypeInfo_t CStrToVoidStarTable = {
- .size=sizeof(Table_t),
- .align=__alignof__(Table_t),
- .tag=TableInfo,
- .TableInfo={.key=&CString$info, .value=&MemoryPointer},
- .metamethods=Table$metamethods,
-};
-
-PUREFUNC static INLINE size_t entry_size(const TypeInfo_t *info)
-{
- size_t size = (size_t)info->TableInfo.key->size;
- if (info->TableInfo.value->align > 1 && size % (size_t)info->TableInfo.value->align)
- size += (size_t)info->TableInfo.value->align - (size % (size_t)info->TableInfo.value->align); // padding
- size += (size_t)info->TableInfo.value->size;
- if (info->TableInfo.key->align > 1 && size % (size_t)info->TableInfo.key->align)
- size += (size_t)info->TableInfo.key->align - (size % (size_t)info->TableInfo.key->align); // padding
- return size;
-}
-
-PUREFUNC static INLINE size_t entry_align(const TypeInfo_t *info)
-{
- return (size_t)MAX(info->TableInfo.key->align, info->TableInfo.value->align);
-}
-
-PUREFUNC static INLINE size_t value_offset(const TypeInfo_t *info)
-{
- size_t offset = (size_t)info->TableInfo.key->size;
- if ((size_t)info->TableInfo.value->align > 1 && offset % (size_t)info->TableInfo.value->align)
- offset += (size_t)info->TableInfo.value->align - (offset % (size_t)info->TableInfo.value->align); // padding
- return offset;
-}
-
-static INLINE void hshow(const Table_t *t)
-{
- hdebug("{");
- for (uint32_t i = 0; t->bucket_info && i < t->bucket_info->count; i++) {
- if (i > 0) hdebug(" ");
- if (t->bucket_info->buckets[i].occupied)
- hdebug("[%d]=%d(%d)", i, t->bucket_info->buckets[i].index, t->bucket_info->buckets[i].next_bucket);
- else
- hdebug("[%d]=_", i);
- }
- hdebug("}\n");
-}
-
-static void maybe_copy_on_write(Table_t *t, const TypeInfo_t *type)
-{
- if (t->entries.data_refcount != 0)
- Array$compact(&t->entries, (int64_t)entry_size(type));
-
- if (t->bucket_info && t->bucket_info->data_refcount != 0) {
- size_t size = sizeof(bucket_info_t) + sizeof(bucket_t[t->bucket_info->count]);
- t->bucket_info = memcpy(GC_MALLOC(size), t->bucket_info, size);
- t->bucket_info->data_refcount = 0;
- }
-}
-
-// Return address of value or NULL
-PUREFUNC public void *Table$get_raw(Table_t t, const void *key, const TypeInfo_t *type)
-{
- assert(type->tag == TableInfo);
- if (!key || !t.bucket_info) return NULL;
-
- uint64_t hash = HASH_KEY(t, key);
- hshow(&t);
- hdebug("Getting value with initial probe at %u\n", hash);
- bucket_t *buckets = t.bucket_info->buckets;
- for (uint64_t i = hash; buckets[i].occupied; i = buckets[i].next_bucket) {
- hdebug("Checking against key in bucket %u\n", i);
- void *entry = GET_ENTRY(t, buckets[i].index);
- if (EQUAL_KEYS(entry, key)) {
- hdebug("Found key!\n");
- return entry + value_offset(type);
- }
- if (buckets[i].next_bucket == END_OF_CHAIN)
- break;
- }
- return NULL;
-}
-
-PUREFUNC public void *Table$get(Table_t t, const void *key, const TypeInfo_t *type)
-{
- assert(type->tag == TableInfo);
- for (const Table_t *iter = &t; iter; iter = iter->fallback) {
- void *ret = Table$get_raw(*iter, key, type);
- if (ret) return ret;
- }
- return NULL;
-}
-
-static void Table$set_bucket(Table_t *t, const void *entry, int32_t index, const TypeInfo_t *type)
-{
- assert(t->bucket_info);
- hshow(t);
- const void *key = entry;
- bucket_t *buckets = t->bucket_info->buckets;
- uint64_t hash = HASH_KEY(*t, key);
- hdebug("Hash value (mod %u) = %u\n", t->bucket_info->count, hash);
- bucket_t *bucket = &buckets[hash];
- if (!bucket->occupied) {
- hdebug("Got an empty space\n");
- // Empty space:
- bucket->occupied = 1;
- bucket->index = index;
- bucket->next_bucket = END_OF_CHAIN;
- hshow(t);
- return;
- }
-
- hdebug("Collision detected in bucket %u (entry %u)\n", hash, bucket->index);
-
- while (buckets[t->bucket_info->last_free].occupied) {
- assert(t->bucket_info->last_free > 0);
- --t->bucket_info->last_free;
- }
-
- uint64_t collided_hash = HASH_KEY(*t, GET_ENTRY(*t, bucket->index));
- if (collided_hash != hash) { // Collided with a mid-chain entry
- hdebug("Hit a mid-chain entry at bucket %u (chain starting at %u)\n", hash, collided_hash);
- // Find chain predecessor
- uint64_t predecessor = collided_hash;
- while (buckets[predecessor].next_bucket != hash)
- predecessor = buckets[predecessor].next_bucket;
-
- // Move mid-chain entry to free space and update predecessor
- buckets[predecessor].next_bucket = t->bucket_info->last_free;
- buckets[t->bucket_info->last_free] = *bucket;
- } else { // Collided with the start of a chain
- hdebug("Hit start of a chain\n");
- uint64_t end_of_chain = hash;
- while (buckets[end_of_chain].next_bucket != END_OF_CHAIN)
- end_of_chain = buckets[end_of_chain].next_bucket;
- hdebug("Appending to chain\n");
- // Chain now ends on the free space:
- buckets[end_of_chain].next_bucket = t->bucket_info->last_free;
- bucket = &buckets[t->bucket_info->last_free];
- }
-
- bucket->occupied = 1;
- bucket->index = index;
- bucket->next_bucket = END_OF_CHAIN;
- hshow(t);
-}
-
-static void hashmap_resize_buckets(Table_t *t, uint32_t new_capacity, const TypeInfo_t *type)
-{
- if (unlikely(new_capacity > TABLE_MAX_BUCKETS))
- fail("Table has exceeded the maximum table size (2^31) and cannot grow further!");
- hdebug("About to resize from %u to %u\n", t->bucket_info ? t->bucket_info->count : 0, new_capacity);
- hshow(t);
- size_t alloc_size = sizeof(bucket_info_t) + sizeof(bucket_t[new_capacity]);
- t->bucket_info = GC_MALLOC_ATOMIC(alloc_size);
- memset(t->bucket_info->buckets, 0, sizeof(bucket_t[new_capacity]));
- t->bucket_info->count = new_capacity;
- t->bucket_info->last_free = new_capacity-1;
- // Rehash:
- for (int64_t i = 0; i < Table$length(*t); i++) {
- hdebug("Rehashing %u\n", i);
- Table$set_bucket(t, GET_ENTRY(*t, i), i, type);
- }
-
- hshow(t);
- hdebug("Finished resizing\n");
-}
-
-// Return address of value
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wstack-protector"
-public void *Table$reserve(Table_t *t, const void *key, const void *value, const TypeInfo_t *type)
-{
- assert(type->tag == TableInfo);
- if (!t || !key) return NULL;
- hshow(t);
-
- t->hash = 0;
-
- int64_t key_size = type->TableInfo.key->size,
- value_size = type->TableInfo.value->size;
- if (!t->bucket_info || t->bucket_info->count == 0) {
- hashmap_resize_buckets(t, 8, type);
- } else {
- // Check if we are clobbering a value:
- void *value_home = Table$get_raw(*t, key, type);
- if (value_home) { // Update existing slot
- // Ensure that `value_home` is still inside t->entries, even if COW occurs
- ptrdiff_t offset = value_home - t->entries.data;
- maybe_copy_on_write(t, type);
- value_home = t->entries.data + offset;
-
- if (value && value_size > 0)
- memcpy(value_home, value, (size_t)value_size);
-
- return value_home;
- }
- }
- // Otherwise add a new entry:
-
- // Resize buckets if necessary
- if (t->entries.length >= (int64_t)t->bucket_info->count) {
- // Current resize policy: +50% at a time:
- uint32_t newsize = MAX(8, (uint32_t)(3*t->bucket_info->count)/2);
- if (unlikely(newsize > TABLE_MAX_BUCKETS))
- newsize = TABLE_MAX_BUCKETS;
- hashmap_resize_buckets(t, newsize, type);
- }
-
- if (!value && value_size > 0) {
- for (Table_t *iter = t->fallback; iter; iter = iter->fallback) {
- value = Table$get_raw(*iter, key, type);
- if (value) break;
- }
- }
-
- maybe_copy_on_write(t, type);
-
- char buf[entry_size(type)];
- memset(buf, 0, sizeof(buf));
- memcpy(buf, key, (size_t)key_size);
- if (value && value_size > 0)
- memcpy(buf + value_offset(type), value, (size_t)value_size);
- else
- memset(buf + value_offset(type), 0, (size_t)value_size);
- Array$insert(&t->entries, buf, I(0), (int64_t)entry_size(type));
-
- int64_t entry_index = t->entries.length-1;
- void *entry = GET_ENTRY(*t, entry_index);
- Table$set_bucket(t, entry, entry_index, type);
- return entry + value_offset(type);
-}
-#pragma GCC diagnostic pop
-
-public void Table$set(Table_t *t, const void *key, const void *value, const TypeInfo_t *type)
-{
- assert(type->tag == TableInfo);
- (void)Table$reserve(t, key, value, type);
-}
-
-public void Table$remove(Table_t *t, const void *key, const TypeInfo_t *type)
-{
- assert(type->tag == TableInfo);
- if (!t || Table$length(*t) == 0) return;
-
- // TODO: this work doesn't need to be done if the key is already missing
- maybe_copy_on_write(t, type);
-
- // If unspecified, pop the last key:
- if (!key)
- key = GET_ENTRY(*t, t->entries.length-1);
-
- // Steps: look up the bucket for the removed key
- // If missing, then return immediately
- // Swap last key/value into the removed bucket's index1
- // Zero out the last key/value and decrement the count
- // Find the last key/value's bucket and update its index1
- // Look up the bucket for the removed key
- // If bucket is first in chain:
- // Move bucket->next to bucket's spot
- // zero out bucket->next's old spot
- // maybe update lastfree_index1 to second-in-chain's index
- // Else:
- // set prev->next = bucket->next
- // zero out bucket
- // maybe update lastfree_index1 to removed bucket's index
-
- uint64_t hash = HASH_KEY(*t, key);
- hdebug("Removing key with hash %u\n", hash);
- bucket_t *bucket, *prev = NULL;
- for (uint64_t i = hash; t->bucket_info->buckets[i].occupied; i = t->bucket_info->buckets[i].next_bucket) {
- if (EQUAL_KEYS(GET_ENTRY(*t, t->bucket_info->buckets[i].index), key)) {
- bucket = &t->bucket_info->buckets[i];
- hdebug("Found key to delete in bucket %u\n", i);
- goto found_it;
- }
- if (t->bucket_info->buckets[i].next_bucket == END_OF_CHAIN)
- return;
- prev = &t->bucket_info->buckets[i];
- }
- return;
-
- found_it:;
- assert(bucket->occupied);
-
- t->hash = 0;
-
- // Always remove the last entry. If we need to remove some other entry,
- // swap the other entry into the last position and then remove the last
- // entry. This disturbs the ordering of the table, but keeps removal O(1)
- // instead of O(N)
- int64_t last_entry = t->entries.length-1;
- if (bucket->index != last_entry) {
- hdebug("Removing key/value from the middle of the entries array\n");
-
- // Find the bucket that points to the last entry's index:
- uint64_t i = HASH_KEY(*t, GET_ENTRY(*t, last_entry));
- while (t->bucket_info->buckets[i].index != last_entry)
- i = t->bucket_info->buckets[i].next_bucket;
- // Update the bucket to point to the last entry's new home (the space
- // where the removed entry currently sits):
- t->bucket_info->buckets[i].index = bucket->index;
-
- // Clobber the entry being removed (in the middle of the array) with
- // the last entry:
- memcpy(GET_ENTRY(*t, bucket->index), GET_ENTRY(*t, last_entry), entry_size(type));
- }
-
- // Last entry is being removed, so clear it out to be safe:
- memset(GET_ENTRY(*t, last_entry), 0, entry_size(type));
-
- Array$remove_at(&t->entries, I(t->entries.length), I(1), (int64_t)entry_size(type));
-
- int64_t bucket_to_clear;
- if (prev) { // Middle (or end) of a chain
- hdebug("Removing from middle of a chain\n");
- bucket_to_clear = (bucket - t->bucket_info->buckets);
- prev->next_bucket = bucket->next_bucket;
- } else if (bucket->next_bucket != END_OF_CHAIN) { // Start of a chain
- hdebug("Removing from start of a chain\n");
- bucket_to_clear = bucket->next_bucket;
- *bucket = t->bucket_info->buckets[bucket_to_clear];
- } else { // Empty chain
- hdebug("Removing from empty chain\n");
- bucket_to_clear = (bucket - t->bucket_info->buckets);
- }
-
- t->bucket_info->buckets[bucket_to_clear] = (bucket_t){0};
- if (bucket_to_clear > t->bucket_info->last_free)
- t->bucket_info->last_free = bucket_to_clear;
-
- hshow(t);
-}
-
-CONSTFUNC public void *Table$entry(Table_t t, int64_t n)
-{
- if (n < 1 || n > Table$length(t))
- return NULL;
- return GET_ENTRY(t, n-1);
-}
-
-public void Table$clear(Table_t *t)
-{
- memset(t, 0, sizeof(Table_t));
-}
-
-public Table_t Table$sorted(Table_t t, const TypeInfo_t *type)
-{
- Closure_t cmp = (Closure_t){.fn=generic_compare, .userdata=(void*)type->TableInfo.key};
- Array_t entries = Array$sorted(t.entries, cmp, (int64_t)entry_size(type));
- return Table$from_entries(entries, type);
-}
-
-PUREFUNC public bool Table$equal(const void *vx, const void *vy, const TypeInfo_t *type)
-{
- if (vx == vy) return true;
- Table_t *x = (Table_t*)vx, *y = (Table_t*)vy;
-
- if (x->hash && y->hash && x->hash != y->hash)
- return false;
-
- assert(type->tag == TableInfo);
- if (x->entries.length != y->entries.length)
- return false;
-
- if ((x->fallback != NULL) != (y->fallback != NULL))
- return false;
-
- const TypeInfo_t *value_type = type->TableInfo.value;
- size_t offset = value_offset(type);
- for (int64_t i = 0; i < x->entries.length; i++) {
- void *x_key = x->entries.data + i*x->entries.stride;
- void *y_value = Table$get_raw(*y, x_key, type);
- if (!y_value) return false;
- void *x_value = x_key + offset;
- if (!generic_equal(y_value, x_value, value_type))
- return false;
- }
- return true;
-}
-
-PUREFUNC public int32_t Table$compare(const void *vx, const void *vy, const TypeInfo_t *type)
-{
- if (vx == vy) return 0;
-
- Table_t *x = (Table_t*)vx, *y = (Table_t*)vy;
- assert(type->tag == TableInfo);
- auto table = type->TableInfo;
-
- // Sort empty tables before non-empty tables:
- if (x->entries.length == 0 || y->entries.length == 0)
- return ((x->entries.length > 0) - (y->entries.length > 0));
-
- // Table comparison rules:
- // - If two tables have different keys, then compare as if comparing a
- // sorted array of the keys of the two tables:
- // `x.keys:sorted() <> y.keys:sorted()`
- // - Otherwise, compare as if comparing arrays of values for the sorted key
- // arrays:
- // `[x[k] for k in x.keys:sorted()] <> [y[k] for k in y.keys:sorted()]`
- //
- // We can do this in _linear_ time if we find the smallest `k` such that
- // `x[k] != y[k]`, as well as the largest key in `x` and `y`.
-
- void *mismatched_key = NULL, *max_x_key = NULL;
- for (int64_t i = 0; i < x->entries.length; i++) {
- void *key = x->entries.data + x->entries.stride * i;
- if (max_x_key == NULL || generic_compare(key, max_x_key, table.key) > 0)
- max_x_key = key;
-
- void *x_value = key + value_offset(type);
- void *y_value = Table$get_raw(*y, key, type);
-
- if (!y_value || (table.value->size > 0 && !generic_equal(x_value, y_value, table.value))) {
- if (mismatched_key == NULL || generic_compare(key, mismatched_key, table.key) < 0)
- mismatched_key = key;
- }
- }
-
- // If the keys are not all equal, we gotta check to see if there exists a
- // `y[k]` such that `k` is smaller than all keys that `x` has and `y` doesn't:
- void *max_y_key = NULL;
- for (int64_t i = 0; i < y->entries.length; i++) {
- void *key = y->entries.data + y->entries.stride * i;
- if (max_y_key == NULL || generic_compare(key, max_y_key, table.key) > 0)
- max_y_key = key;
-
- void *y_value = key + value_offset(type);
- void *x_value = Table$get_raw(*x, key, type);
- if (!x_value || !generic_equal(x_value, y_value, table.value)) {
- if (mismatched_key == NULL || generic_compare(key, mismatched_key, table.key) < 0)
- mismatched_key = key;
- }
- }
-
- if (mismatched_key) {
- void *x_value = Table$get_raw(*x, mismatched_key, type);
- void *y_value = Table$get_raw(*y, mismatched_key, type);
- if (x_value && y_value) {
- return generic_compare(x_value, y_value, table.value);
- } else if (y_value) {
- // The smallest mismatched key is in Y, but not X.
- // In this case, we should judge if the key is smaller than *any*
- // key in X or if it's bigger than *every* key in X.
- // Example 1:
- // x={10, 20, 30} > y={10, 20, 25, 30}
- // The smallest mismatched key is `25`, and we know that `x` is
- // larger than `y` because `30 > 25`.
- // Example 2:
- // x={10, 20, 30} > y={10, 20, 30, 999}
- // The smallest mismatched key is `999`, and we know that `x` is
- // smaller than `y` because `30 < 999`.
- return max_x_key ? generic_compare(max_x_key, mismatched_key, table.key) : -1;
- } else {
- assert(x_value);
- // The smallest mismatched key is in X, but not Y. The same logic
- // above applies, but reversed.
- return max_y_key ? -generic_compare(max_y_key, mismatched_key, table.key) : 1;
- }
- }
-
- assert(x->entries.length == y->entries.length);
-
- // Assuming keys are the same, compare values:
- if (table.value->size > 0) {
- for (int64_t i = 0; i < x->entries.length; i++) {
- void *key = x->entries.data + x->entries.stride * i;
- void *x_value = key + value_offset(type);
- void *y_value = Table$get_raw(*y, key, type);
- int32_t diff = generic_compare(x_value, y_value, table.value);
- if (diff != 0) return diff;
- }
- }
-
- if (!x->fallback != !y->fallback) {
- return (!x->fallback) - (!y->fallback);
- } else if (x->fallback && y->fallback) {
- return generic_compare(x->fallback, y->fallback, type);
- }
-
- return 0;
-}
-
-PUREFUNC public uint64_t Table$hash(const void *obj, const TypeInfo_t *type)
-{
- assert(type->tag == TableInfo);
- Table_t *t = (Table_t*)obj;
- if (t->hash != 0)
- return t->hash;
-
- // Table hashes are computed as:
- // hash(t.length, (xor: t.keys), (xor: t.values), t.fallback)
- // Where fallback and default hash to zero if absent
- auto table = type->TableInfo;
- uint64_t keys_hash = 0, values_hash = 0;
- size_t offset = value_offset(type);
- if (table.value->size > 0) {
- for (int64_t i = 0; i < t->entries.length; i++) {
- keys_hash ^= generic_hash(t->entries.data + i*t->entries.stride, table.key);
- values_hash ^= generic_hash(t->entries.data + i*t->entries.stride + offset, table.value);
- }
- } else {
- for (int64_t i = 0; i < t->entries.length; i++)
- keys_hash ^= generic_hash(t->entries.data + i*t->entries.stride, table.key);
- }
-
- struct {
- int64_t length;
- uint64_t keys_hash, values_hash;
- Table_t *fallback;
- } components = {
- t->entries.length,
- keys_hash,
- values_hash,
- t->fallback,
- };
- t->hash = siphash24((void*)&components, sizeof(components));
- if unlikely (t->hash == 0)
- t->hash = 1234567;
- return t->hash;
-}
-
-public Text_t Table$as_text(const void *obj, bool colorize, const TypeInfo_t *type)
-{
- Table_t *t = (Table_t*)obj;
- assert(type->tag == TableInfo);
- auto table = type->TableInfo;
-
- if (!t) {
- if (table.value != &Void$info)
- return Text$concat(
- Text("{"),
- generic_as_text(NULL, false, table.key),
- Text(","),
- generic_as_text(NULL, false, table.value),
- Text("}"));
- else
- return Text$concat(
- Text("{"),
- generic_as_text(NULL, false, table.key),
- Text("}"));
- }
-
- int64_t val_off = (int64_t)value_offset(type);
- Text_t text = Text("{");
- for (int64_t i = 0, length = Table$length(*t); i < length; i++) {
- if (i > 0)
- text = Text$concat(text, Text(", "));
- void *entry = GET_ENTRY(*t, i);
- text = Text$concat(text, generic_as_text(entry, colorize, table.key));
- if (table.value != &Void$info)
- text = Text$concat(text, Text("="), generic_as_text(entry + val_off, colorize, table.value));
- }
-
- if (t->fallback) {
- text = Text$concat(text, Text("; fallback="), Table$as_text(t->fallback, colorize, type));
- }
-
- text = Text$concat(text, Text("}"));
- return text;
-}
-
-public Table_t Table$from_entries(Array_t entries, const TypeInfo_t *type)
-{
- assert(type->tag == TableInfo);
- if (entries.length == 0)
- return (Table_t){};
-
- Table_t t = {};
- int64_t length = entries.length + entries.length / 4;
- size_t alloc_size = sizeof(bucket_info_t) + sizeof(bucket_t[length]);
- t.bucket_info = GC_MALLOC_ATOMIC(alloc_size);
- memset(t.bucket_info->buckets, 0, sizeof(bucket_t[length]));
- t.bucket_info->count = length;
- t.bucket_info->last_free = length-1;
-
- size_t offset = value_offset(type);
- for (int64_t i = 0; i < entries.length; i++) {
- void *key = entries.data + i*entries.stride;
- Table$set(&t, key, key + offset, type);
- }
- return t;
-}
-
-// Overlap is "set intersection" in formal terms
-public Table_t Table$overlap(Table_t a, Table_t b, const TypeInfo_t *type)
-{
- // Return a table such that t[k]==a[k] for all k such that a:has(k), b:has(k), and a[k]==b[k]
- Table_t result = {};
- const size_t offset = value_offset(type);
- for (int64_t i = 0; i < Table$length(a); i++) {
- void *key = GET_ENTRY(a, i);
- void *a_value = key + offset;
- void *b_value = Table$get(b, key, type);
- if (b_value && generic_equal(a_value, b_value, type->TableInfo.value))
- Table$set(&result, key, a_value, type);
- }
-
- if (a.fallback) {
- result.fallback = new(Table_t);
- *result.fallback = Table$overlap(*a.fallback, b, type);
- }
-
- return result;
-}
-
-// With is "set union" in formal terms
-public Table_t Table$with(Table_t a, Table_t b, const TypeInfo_t *type)
-{
- // return a table such that t[k]==b[k] for all k such that b:has(k), and t[k]==a[k] for all k such that a:has(k) and not b:has(k)
- Table_t result = {};
- const size_t offset = value_offset(type);
- for (int64_t i = 0; i < Table$length(a); i++) {
- void *key = GET_ENTRY(a, i);
- Table$set(&result, key, key + offset, type);
- }
- for (int64_t i = 0; i < Table$length(b); i++) {
- void *key = GET_ENTRY(b, i);
- Table$set(&result, key, key + offset, type);
- }
-
- if (a.fallback && b.fallback) {
- result.fallback = new(Table_t);
- *result.fallback = Table$with(*a.fallback, *b.fallback, type);
- } else {
- result.fallback = a.fallback ? a.fallback : b.fallback;
- }
-
- return result;
-}
-
-// Without is "set difference" in formal terms
-public Table_t Table$without(Table_t a, Table_t b, const TypeInfo_t *type)
-{
- // Return a table such that t[k]==a[k] for all k such that not b:has(k) or b[k] != a[k]
- Table_t result = {};
- const size_t offset = value_offset(type);
- for (int64_t i = 0; i < Table$length(a); i++) {
- void *key = GET_ENTRY(a, i);
- void *a_value = key + offset;
- void *b_value = Table$get(b, key, type);
- if (!b_value || !generic_equal(a_value, b_value, type->TableInfo.value))
- Table$set(&result, key, a_value, type);
- }
-
- if (a.fallback) {
- result.fallback = new(Table_t);
- *result.fallback = Table$without(*a.fallback, b, type);
- }
-
- return result;
-}
-
-PUREFUNC public bool Table$is_subset_of(Table_t a, Table_t b, bool strict, const TypeInfo_t *type)
-{
- if (a.entries.length > b.entries.length || (strict && a.entries.length == b.entries.length))
- return false;
-
- for (int64_t i = 0; i < Table$length(a); i++) {
- void *found = Table$get_raw(b, GET_ENTRY(a, i), type);
- if (!found) return false;
- }
- return true;
-}
-
-PUREFUNC public bool Table$is_superset_of(Table_t a, Table_t b, bool strict, const TypeInfo_t *type)
-{
- return Table$is_subset_of(b, a, strict, type);
-}
-
-PUREFUNC public void *Table$str_get(Table_t t, const char *key)
-{
- void **ret = Table$get(t, &key, &CStrToVoidStarTable);
- return ret ? *ret : NULL;
-}
-
-PUREFUNC public void *Table$str_get_raw(Table_t t, const char *key)
-{
- void **ret = Table$get_raw(t, &key, &CStrToVoidStarTable);
- return ret ? *ret : NULL;
-}
-
-public void *Table$str_reserve(Table_t *t, const char *key, const void *value)
-{
- return Table$reserve(t, &key, &value, &CStrToVoidStarTable);
-}
-
-public void Table$str_set(Table_t *t, const char *key, const void *value)
-{
- Table$set(t, &key, &value, &CStrToVoidStarTable);
-}
-
-public void Table$str_remove(Table_t *t, const char *key)
-{
- return Table$remove(t, &key, &CStrToVoidStarTable);
-}
-
-CONSTFUNC public void *Table$str_entry(Table_t t, int64_t n)
-{
- return Table$entry(t, n);
-}
-
-PUREFUNC public bool Table$is_none(const void *obj, const TypeInfo_t*)
-{
- return ((Table_t*)obj)->entries.length < 0;
-}
-
-public void Table$serialize(const void *obj, FILE *out, Table_t *pointers, const TypeInfo_t *type)
-{
- Table_t *t = (Table_t*)obj;
- int64_t len = t->entries.length;
- Int64$serialize(&len, out, pointers, &Int64$info);
-
- size_t offset = value_offset(type);
- for (int64_t i = 0; i < len; i++) {
- _serialize(t->entries.data + i*t->entries.stride, out, pointers, type->TableInfo.key);
- _serialize(t->entries.data + i*t->entries.stride + offset, out, pointers, type->TableInfo.value);
- }
-
- Optional$serialize(&t->fallback, out, pointers, Optional$info(sizeof(void*), __alignof__(void*), Pointer$info("&", type)));
-}
-
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wstack-protector"
-public void Table$deserialize(FILE *in, void *outval, Array_t *pointers, const TypeInfo_t *type)
-{
- int64_t len;
- Int64$deserialize(in, &len, pointers, &Int$info);
-
- Table_t t = {};
- for (int64_t i = 0; i < len; i++) {
- char key[type->TableInfo.key->size];
- _deserialize(in, key, pointers, type->TableInfo.key);
- char value[type->TableInfo.value->size];
- _deserialize(in, value, pointers, type->TableInfo.value);
- Table$set(&t, key, value, type);
- }
-
- Optional$deserialize(in, &t.fallback, pointers, Optional$info(sizeof(void*), __alignof__(void*), Pointer$info("&", type)));
-
- *(Table_t*)outval = t;
-}
-#pragma GCC diagnostic pop
-
-// vim: ts=4 sw=0 et cino=L2,l1,(0,W4,m1