Restructure into src/{std,json}/

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 282 insertions, 0 deletions

diff --git a/src/json/json.c b/src/json/json.c
new file mode 100644
index 0000000..d16415b
--- /dev/null
+++ b/src/json/json.c
@@ -0,0 +1,282 @@
+#include <ctype.h>
+#include <immintrin.h>
+#include <math.h>
+#include <stdbit.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "../std/assert.h"
+#include "json.h"
+#include "../std/str.h"
+#include "../std/types.h"
+
+JSONObject *JSONObject_new(Arena *a) {
+    JSONObject *object = new(a, JSONObject, 1);
+    object->len = 0;
+    object->keys = Vec_new(a, StrView, 2);
+    object->values = Vec_new(a, JSON, 2);
+    return object;
+}
+
+JSON JSON_integer(i32 value) {
+    JSON json = {0};
+    json.type = JSON_INTEGER;
+    json.as.integer = value;
+    return json;
+}
+
+JSON JSON_float(f32 value) {
+    JSON json = {0};
+    json.type = JSON_FLOAT;
+    json.as.floating = value;
+    return json;
+}
+
+JSON JSON_array(Vec items) {
+    JSON json = {0};
+    json.type = JSON_ARRAY;
+    json.as.array = items;
+    return json;
+}
+
+JSON JSON_string(StrView value) {
+    JSON json = {0};
+    json.type = JSON_STRING;
+    json.as.string = value;
+    return json;
+}
+
+JSON JSON_object(size len, Vec keys, Vec values) {
+    assert(len == keys.len && len == values.len, "length mismatch");
+    JSON json = {0};
+    json.type = JSON_OBJECT;
+    json.as.object.len = len;
+    json.as.object.keys = keys;
+    json.as.object.values = values;
+    return json;
+}
+
+JSON JSON_boolean(bool value) {
+    JSON json = {0};
+    json.type = JSON_BOOL;
+    json.as.boolean = value;
+    return json;
+}
+
+JSON JSON_null() {
+    JSON json = {0};
+    json.type = JSON_NULL;
+    return json;
+}
+
+i32 JSON_fprint(FILE *w, JSON json) {
+    switch (json.type) {
+    case JSON_STRING:
+        fprintf(w, "\"");
+        Str_fprint(w, json.as.string);
+        return fprintf(w, "\"");
+    case JSON_INTEGER:
+        return fprintf(w, "%d", json.as.integer);
+    case JSON_FLOAT:
+        return fprintf(w, "%f", json.as.floating);
+    case JSON_NULL:
+        return fprintf(w, "null");
+    case JSON_BOOL:
+        return fprintf(w, "%s", json.as.boolean ? "true" : "false");
+    case JSON_ARRAY:
+        fprintf(w, "[");
+        for (size i = 0; i < json.as.array.len; i++) {
+            JSON value = *Vec_get(json.as.array, JSON, i);
+            JSON_fprint(w, value);
+            if (i < json.as.array.len - 1) fprintf(w, ", ");
+        }
+        fprintf(w, "]");
+        return 0;
+    case JSON_OBJECT:
+        fprintf(w, "{");
+        for (size i = 0; i < json.as.object.len; i++) {
+            StrView key = *Vec_get(json.as.object.keys, StrView, i);
+            fprintf(w, "\"");
+            Str_fprint(w, key);
+            fprintf(w, "\": ");
+            JSON value = *Vec_get(json.as.object.values, JSON, i);
+            JSON_fprint(w, value);
+            if (i < json.as.object.len - 1) fprintf(w, ", ");
+        }
+        fprintf(w, "}");
+        return 0;
+    }
+    assert(false, "unknown json type %d", json.type);
+}
+
+typedef struct {
+    JSON value;
+    uptr pos;
+} parse_result;
+
+#define assert_parse(condition, msg, src, pos)                                 \
+    assert(condition, "%s (%c at %lu)", msg, src[pos], pos)
+
+parse_result parse_any(Arena *a, byte *src, uptr pos, uptr max_pos);
+
+parse_result parse_number(byte *src, uptr start_pos) {
+    parse_result result = {0};
+    byte *end;
+    f32 number = strtod(src + start_pos, &end);
+    assert_parse(end != src, "invalide number", src, result.pos);
+    result.pos += end - src;
+    result.value =
+        floor(number) == number ? JSON_integer(number) : JSON_float(number);
+    return result;
+}
+
+uptr absorb_whitespaces(byte *src, uptr start_pos, uptr max_pos) {
+    uptr pos = start_pos;
+    while (pos < max_pos && isspace(src[pos])) {
+        pos++;
+    }
+    return pos;
+}
+
+parse_result parse_array(Arena *a, byte *src, uptr start_pos, uptr max_pos) {
+    assert_parse(src[start_pos] == '[', "invalid array start", src, start_pos);
+    parse_result result = {0};
+    result.pos = start_pos + 1;
+    if (src[result.pos] == ']') {
+        result.pos++;
+        return result;
+    }
+    Vec items = Vec_new(a, JSON, 6);
+    for (;;) {
+        result.pos = absorb_whitespaces(src, result.pos, max_pos);
+        parse_result item_result = parse_any(a, src, result.pos, max_pos);
+        Vec_push(a, &items, &item_result.value);
+        result.pos = absorb_whitespaces(src, item_result.pos, max_pos);
+        if (src[result.pos] == ',') {
+            result.pos++;
+        } else {
+            break;
+        }
+    };
+    assert_parse(src[result.pos] == ']', "invalid array end", src, result.pos);
+    result.pos++;
+    result.value = JSON_array(items);
+    return result;
+}
+
+parse_result parse_string(byte *src, uptr start_pos, uptr max_pos) {
+    assert_parse(src[start_pos] == '"', "invalid string start", src, start_pos);
+    parse_result result = {0};
+    result.pos = start_pos + 1;
+
+    // SIMD optimization: process 32 bytes at a time using AVX2
+    bytex32 quote_bytes = _mm256_set1_epi8('"');
+
+    for (; result.pos + 32 <= max_pos; result.pos += 32) {
+        bytex32 chunk = _mm256_loadu_si256((bytex32 *)(src + result.pos));
+        i32 quote_mask =
+            _mm256_movemask_epi8(_mm256_cmpeq_epi8(chunk, quote_bytes));
+
+        if (quote_mask != 0) {
+            result.pos += stdc_trailing_zeros_ui(quote_mask);
+            break;
+        };
+    }
+
+    // Fall back to original byte-by-byte processing for the remaining bytes
+    for (; result.pos < max_pos; result.pos++) {
+        if (src[result.pos] == '"') {
+            uptr backslash_count = 0;
+            while (backslash_count < result.pos &&
+                   src[result.pos - backslash_count - 1] == '\\') {
+                backslash_count++;
+            }
+            if (!(backslash_count & 1)) break;
+        }
+    }
+
+    assert_parse(src[result.pos] == '"', "invalid string end", src, result.pos);
+    result.value =
+        JSON_string(Str_view(&src[start_pos + 1], result.pos - start_pos - 1));
+    result.pos++;
+
+    return result;
+}
+
+parse_result parse_object(Arena *a, byte *src, uptr start_pos, uptr max_pos) {
+    assert_parse(src[start_pos] == '{', "invalid object start", src, start_pos);
+    parse_result result = {0};
+    result.pos = absorb_whitespaces(src, start_pos + 1, max_pos);
+    size len = 0;
+    Vec keys = Vec_new(a, StrView, 6);
+    Vec values = Vec_new(a, JSON, 6);
+    if (src[result.pos] == '}') {
+        result.pos++;
+        result.value = JSON_object(len, keys, values);
+        return result;
+    }
+    for (;;) {
+        parse_result key_result = parse_string(src, result.pos, max_pos);
+        result.pos = absorb_whitespaces(src, key_result.pos, max_pos);
+        assert_parse(src[result.pos] == ':', "invalid keyval delim", src,
+                     result.pos);
+        result.pos = absorb_whitespaces(src, result.pos + 1, max_pos);
+        parse_result value_result = parse_any(a, src, result.pos, max_pos);
+        len++;
+        assert(key_result.value.type == JSON_STRING,
+               "invalid json type for key: %d", key_result.value.type);
+        Vec_push(a, &keys, &key_result.value.as.string);
+        Vec_push(a, &values, &value_result.value);
+        result.pos = absorb_whitespaces(src, value_result.pos, max_pos);
+        if (src[result.pos] != ',') {
+            break;
+        }
+        result.pos = absorb_whitespaces(src, result.pos + 1, max_pos);
+    }
+    assert_parse(src[result.pos] == '}', "invalid object end", src, result.pos);
+    result.pos++;
+    result.value = JSON_object(len, keys, values);
+    return result;
+}
+
+parse_result parse_any(Arena *a, byte *src, uptr pos, uptr max_pos) {
+    pos = absorb_whitespaces(src, pos, max_pos);
+    if (isdigit(src[pos]) || src[pos] == '-') return parse_number(src, pos);
+    if (src[pos] == '[') return parse_array(a, src, pos, max_pos);
+    if (src[pos] == '"') return parse_string(src, pos, max_pos);
+    if (src[pos] == '{') return parse_object(a, src, pos, max_pos);
+    if (memcmp(src + pos, "true", 4) == 0) {
+        parse_result result = {0};
+        result.value = JSON_boolean(true);
+        result.pos = pos + 4;
+        return result;
+    }
+    if (memcmp(src + pos, "false", 5) == 0) {
+        parse_result result = {0};
+        result.value = JSON_boolean(false);
+        result.pos = pos + 5;
+        return result;
+    }
+    if (memcmp(src + pos, "null", 4) == 0) {
+        parse_result result = {0};
+        result.value = JSON_null();
+        result.pos = pos + 4;
+        return result;
+    }
+    assert_parse(false, "unexpected input", src, pos);
+}
+
+JSON JSON_parse(Arena *a, byte *src, uptr len) {
+    return parse_any(a, src, 0, len).value;
+}
+
+JSON *JSONObject_get(JSONObject obj, Str key) {
+    for (size i = 0; i < obj.len; i++) {
+        StrView tmp_key = *Vec_get(obj.keys, StrView, i);
+        if (Str_equals(tmp_key, key)) return Vec_get(obj.values, JSON, i);
+    }
+    return 0;
+}