quickjs/src/crc32.c

   1 #include "a.h"
   2 #include "a/crc.h"
   3
   4 struct crc32
   5 {
   6     a_u32 table[0x100];
   7     a_u32 (*eval)(a_u32 const table[0x100], void const *pdata, a_size nbyte, a_u32 value);
   8 };
   9
  10 static JSClassID liba_crc32_class_id;
  11
  12 static void liba_crc32_finalizer(JSRuntime *rt, JSValue val)
  13 {
  14     js_free_rt(rt, JS_GetOpaque(val, liba_crc32_class_id));
  15 }
  16
  17 static JSClassDef liba_crc32_class = {"crc32", .finalizer = liba_crc32_finalizer};
  18
  19 static JSValue liba_crc32_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst *argv)
  20 {
  21     JSValue proto, clazz = JS_UNDEFINED;
  22     struct crc32 *const self = (struct crc32 *)js_mallocz(ctx, sizeof(struct crc32));
  23     if (!self) { return JS_EXCEPTION; }
  24     a_u32 poly = 0;
  25     if (JS_ToUint32(ctx, &poly, argv[0])) { goto fail; }
  26     int reversed = 0;
  27     if (argc > 1)
  28     {
  29         reversed = JS_ToBool(ctx, argv[1]);
  30         if (reversed < 0) { goto fail; }
  31     }
  32     if (reversed)
  33     {
  34         a_crc32l_init(self->table, poly);
  35         self->eval = a_crc32l;
  36     }
  37     else
  38     {
  39         a_crc32m_init(self->table, poly);
  40         self->eval = a_crc32m;
  41     }
  42     proto = JS_GetPropertyStr(ctx, new_target, "prototype");
  43     if (JS_IsException(proto)) { goto fail; }
  44     clazz = JS_NewObjectProtoClass(ctx, proto, liba_crc32_class_id);
  45     JS_FreeValue(ctx, proto);
  46     if (JS_IsException(clazz)) { goto fail; }
  47     JS_SetOpaque(clazz, self);
  48     return clazz;
  49 fail:
  50     js_free(ctx, self);
  51     JS_FreeValue(ctx, clazz);
  52     return JS_UNDEFINED;
  53 }
  54
  55 static JSValue liba_crc32_get(JSContext *ctx, JSValueConst this_val, int magic)
  56 {
  57     struct crc32 *const self = (struct crc32 *)JS_GetOpaque2(ctx, this_val, liba_crc32_class_id);
  58     if (!self) { return JS_EXCEPTION; }
  59     if (magic == 0)
  60     {
  61         return js_array_u32_new(ctx, self->table, 0x100);
  62     }
  63     return JS_UNDEFINED;
  64 }
  65
  66 static JSValue liba_crc32_gen(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
  67 {
  68     struct crc32 *const self = (struct crc32 *)JS_GetOpaque2(ctx, this_val, liba_crc32_class_id);
  69     if (!self) { return JS_EXCEPTION; }
  70     a_u32 poly = 0;
  71     if (JS_ToUint32(ctx, &poly, argv[0])) { return JS_EXCEPTION; }
  72     int reversed = 0;
  73     if (argc > 1)
  74     {
  75         reversed = JS_ToBool(ctx, argv[1]);
  76         if (reversed < 0) { return JS_EXCEPTION; }
  77     }
  78     if (reversed)
  79     {
  80         a_crc32l_init(self->table, poly);
  81         self->eval = a_crc32l;
  82     }
  83     else
  84     {
  85         a_crc32m_init(self->table, poly);
  86         self->eval = a_crc32m;
  87     }
  88     return JS_UNDEFINED;
  89 }
  90
  91 static JSValue liba_crc32_eval(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
  92 {
  93     struct crc32 *const self = (struct crc32 *)JS_GetOpaque2(ctx, this_val, liba_crc32_class_id);
  94     if (!self) { return JS_EXCEPTION; }
  95     a_u32 value = 0;
  96     if (argc > 1)
  97     {
  98         if (JS_ToUint32(ctx, &value, argv[1])) { return JS_EXCEPTION; }
  99     }
 100     size_t n = 0;
 101     if (JS_IsArray(ctx, argv[0]))
 102     {
 103         a_byte *p = JS_GetArrayBuffer(ctx, &n, argv[0]);
 104         if (p) { value = self->eval(self->table, p, n, value); }
 105     }
 106     else
 107     {
 108         char const *const p = JS_ToCStringLen(ctx, &n, argv[0]);
 109         value = self->eval(self->table, p, n, value);
 110         JS_FreeCString(ctx, p);
 111     }
 112     return JS_NewUint32(ctx, value);
 113 }
 114
 115 static JSValue liba_crc32_pack(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
 116 {
 117     JSValue val = JS_UNDEFINED;
 118     struct crc32 *const self = (struct crc32 *)JS_GetOpaque2(ctx, this_val, liba_crc32_class_id);
 119     if (!self) { return JS_EXCEPTION; }
 120     a_u32 value = 0;
 121     if (argc > 1)
 122     {
 123         if (JS_ToUint32(ctx, &value, argv[1])) { return JS_EXCEPTION; }
 124     }
 125     size_t n = 0;
 126     char const *const s = JS_ToCStringLen(ctx, &n, argv[0]);
 127     value = self->eval(self->table, s, n, value);
 128     a_byte *p = (a_byte *)js_malloc(ctx, n + 4);
 129     if (p) { a_copy(p, s, n); }
 130     else { goto fail; }
 131     self->eval == a_crc32m
 132         ? a_u32_setb(p + n, value)
 133         : a_u32_setl(p + n, value);
 134     val = js_array_u8_new(ctx, p, (uint32_t)n + 4);
 135 fail:
 136     JS_FreeCString(ctx, s);
 137     js_free(ctx, p);
 138     return val;
 139 }
 140
 141 static JSCFunctionListEntry const liba_crc32_proto[] = {
 142     JS_PROP_STRING_DEF("[Symbol.toStringTag]", "a.crc32", 0),
 143     JS_CGETSET_MAGIC_DEF("table", liba_crc32_get, NULL, 0),
 144     JS_CFUNC_DEF("gen", 2, liba_crc32_gen),
 145     JS_CFUNC_DEF("eval", 2, liba_crc32_eval),
 146     JS_CFUNC_DEF("pack", 2, liba_crc32_pack),
 147 };
 148
 149 int js_liba_crc32_init(JSContext *ctx, JSModuleDef *m)
 150 {
 151     JS_NewClassID(&liba_crc32_class_id);
 152     JS_NewClass(JS_GetRuntime(ctx), liba_crc32_class_id, &liba_crc32_class);
 153
 154     JSValue const proto = JS_NewObject(ctx);
 155     JS_SetPropertyFunctionList(ctx, proto, liba_crc32_proto, A_LEN(liba_crc32_proto));
 156
 157     JSValue const clazz = JS_NewCFunction2(ctx, liba_crc32_ctor, "crc32", 2, JS_CFUNC_constructor, 0);
 158     JS_SetConstructor(ctx, clazz, proto);
 159     JS_SetClassProto(ctx, liba_crc32_class_id, proto);
 160
 161     return JS_SetModuleExport(ctx, m, "crc32", clazz);
 162 }