quickjs/src/crc16.c

   1 #include "a.h"
   2 #include "a/crc.h"
   3
   4 struct crc16
   5 {
   6     a_u16 table[0x100];
   7     a_u16 (*eval)(a_u16 const table[0x100], void const *pdata, a_size nbyte, a_u16 value);
   8 };
   9
  10 static JSClassID liba_crc16_class_id;
  11
  12 static void liba_crc16_finalizer(JSRuntime *rt, JSValue val)
  13 {
  14     js_free_rt(rt, JS_GetOpaque(val, liba_crc16_class_id));
  15 }
  16
  17 static JSClassDef liba_crc16_class = {"crc16", .finalizer = liba_crc16_finalizer};
  18
  19 static JSValue liba_crc16_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst *argv)
  20 {
  21     JSValue proto, clazz = JS_UNDEFINED;
  22     struct crc16 *const self = (struct crc16 *)js_mallocz(ctx, sizeof(struct crc16));
  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_crc16l_init(self->table, (a_u16)poly);
  35         self->eval = a_crc16l;
  36     }
  37     else
  38     {
  39         a_crc16m_init(self->table, (a_u16)poly);
  40         self->eval = a_crc16m;
  41     }
  42     proto = JS_GetPropertyStr(ctx, new_target, "prototype");
  43     if (JS_IsException(proto)) { goto fail; }
  44     clazz = JS_NewObjectProtoClass(ctx, proto, liba_crc16_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_crc16_get(JSContext *ctx, JSValueConst this_val, int magic)
  56 {
  57     struct crc16 *const self = (struct crc16 *)JS_GetOpaque2(ctx, this_val, liba_crc16_class_id);
  58     if (!self) { return JS_EXCEPTION; }
  59     if (magic == 0)
  60     {
  61         return js_array_u16_new(ctx, self->table, 0x100);
  62     }
  63     return JS_UNDEFINED;
  64 }
  65
  66 static JSValue liba_crc16_gen(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
  67 {
  68     struct crc16 *const self = (struct crc16 *)JS_GetOpaque2(ctx, this_val, liba_crc16_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_crc16l_init(self->table, (a_u16)poly);
  81         self->eval = a_crc16l;
  82     }
  83     else
  84     {
  85         a_crc16m_init(self->table, (a_u16)poly);
  86         self->eval = a_crc16m;
  87     }
  88     return JS_UNDEFINED;
  89 }
  90
  91 static JSValue liba_crc16_eval(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
  92 {
  93     struct crc16 *const self = (struct crc16 *)JS_GetOpaque2(ctx, this_val, liba_crc16_class_id);
  94     if (!self) { return JS_EXCEPTION; }
  95     a_u16 value = 0;
  96     if (argc > 1)
  97     {
  98         a_u32 x = 0;
  99         if (JS_ToUint32(ctx, &x, argv[1])) { return JS_EXCEPTION; }
 100         value = (a_u16)x;
 101     }
 102     size_t n = 0;
 103     if (JS_IsArray(ctx, argv[0]))
 104     {
 105         a_byte *p = JS_GetArrayBuffer(ctx, &n, argv[0]);
 106         if (p) { value = self->eval(self->table, p, n, value); }
 107     }
 108     else
 109     {
 110         char const *const p = JS_ToCStringLen(ctx, &n, argv[0]);
 111         value = self->eval(self->table, p, n, value);
 112         JS_FreeCString(ctx, p);
 113     }
 114     return JS_NewUint32(ctx, value);
 115 }
 116
 117 static JSValue liba_crc16_pack(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
 118 {
 119     JSValue val = JS_UNDEFINED;
 120     struct crc16 *const self = (struct crc16 *)JS_GetOpaque2(ctx, this_val, liba_crc16_class_id);
 121     if (!self) { return JS_EXCEPTION; }
 122     a_u16 value = 0;
 123     if (argc > 1)
 124     {
 125         a_u32 x = 0;
 126         if (JS_ToUint32(ctx, &x, argv[1])) { return JS_EXCEPTION; }
 127         value = (a_u16)x;
 128     }
 129     size_t n = 0;
 130     char const *const s = JS_ToCStringLen(ctx, &n, argv[0]);
 131     value = self->eval(self->table, s, n, value);
 132     a_byte *p = (a_byte *)js_malloc(ctx, n + 2);
 133     if (p) { a_copy(p, s, n); }
 134     else { goto fail; }
 135     self->eval == a_crc16m
 136         ? a_u16_setb(p + n, value)
 137         : a_u16_setl(p + n, value);
 138     val = js_array_u8_new(ctx, p, (uint32_t)n + 2);
 139 fail:
 140     JS_FreeCString(ctx, s);
 141     js_free(ctx, p);
 142     return val;
 143 }
 144
 145 static JSCFunctionListEntry const liba_crc16_proto[] = {
 146     JS_PROP_STRING_DEF("[Symbol.toStringTag]", "a.crc16", 0),
 147     JS_CGETSET_MAGIC_DEF("table", liba_crc16_get, NULL, 0),
 148     JS_CFUNC_DEF("gen", 2, liba_crc16_gen),
 149     JS_CFUNC_DEF("eval", 2, liba_crc16_eval),
 150     JS_CFUNC_DEF("pack", 2, liba_crc16_pack),
 151 };
 152
 153 int js_liba_crc16_init(JSContext *ctx, JSModuleDef *m)
 154 {
 155     JS_NewClassID(&liba_crc16_class_id);
 156     JS_NewClass(JS_GetRuntime(ctx), liba_crc16_class_id, &liba_crc16_class);
 157
 158     JSValue const proto = JS_NewObject(ctx);
 159     JS_SetPropertyFunctionList(ctx, proto, liba_crc16_proto, A_LEN(liba_crc16_proto));
 160
 161     JSValue const clazz = JS_NewCFunction2(ctx, liba_crc16_ctor, "crc16", 2, JS_CFUNC_constructor, 0);
 162     JS_SetConstructor(ctx, clazz, proto);
 163     JS_SetClassProto(ctx, liba_crc16_class_id, proto);
 164
 165     return JS_SetModuleExport(ctx, m, "crc16", clazz);
 166 }