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 JSValue liba_crc16_ctor(JSContext *ctx, JSValueConst new_target, int argc, JSValueConst *argv)
  18 {
  19     a_u32 poly = 0;
  20     int reversed = 0;
  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     if (JS_ToUint32(ctx, &poly, argv[0])) { goto fail; }
  25     if (argc > 1)
  26     {
  27         reversed = JS_ToBool(ctx, argv[1]);
  28         if (reversed < 0) { goto fail; }
  29     }
  30     if (reversed)
  31     {
  32         a_crc16l_init(self->table, (a_u16)poly);
  33         self->eval = a_crc16l;
  34     }
  35     else
  36     {
  37         a_crc16m_init(self->table, (a_u16)poly);
  38         self->eval = a_crc16m;
  39     }
  40     proto = JS_GetPropertyStr(ctx, new_target, "prototype");
  41     if (JS_IsException(proto)) { goto fail; }
  42     clazz = JS_NewObjectProtoClass(ctx, proto, liba_crc16_class_id);
  43     JS_FreeValue(ctx, proto);
  44     if (JS_IsException(clazz)) { goto fail; }
  45     JS_SetOpaque(clazz, self);
  46     return clazz;
  47 fail:
  48     js_free(ctx, self);
  49     JS_FreeValue(ctx, clazz);
  50     return JS_UNDEFINED;
  51 }
  52
  53 static JSValue liba_crc16_gen(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
  54 {
  55     a_u32 poly = 0;
  56     int reversed = 0;
  57     struct crc16 *const self = (struct crc16 *)JS_GetOpaque2(ctx, this_val, liba_crc16_class_id);
  58     if (!self) { return JS_EXCEPTION; }
  59     if (JS_ToUint32(ctx, &poly, argv[0])) { return JS_EXCEPTION; }
  60     if (argc > 1)
  61     {
  62         reversed = JS_ToBool(ctx, argv[1]);
  63         if (reversed < 0) { return JS_EXCEPTION; }
  64     }
  65     if (reversed)
  66     {
  67         a_crc16l_init(self->table, (a_u16)poly);
  68         self->eval = a_crc16l;
  69     }
  70     else
  71     {
  72         a_crc16m_init(self->table, (a_u16)poly);
  73         self->eval = a_crc16m;
  74     }
  75     return JS_UNDEFINED;
  76 }
  77
  78 static JSValue liba_crc16_eval(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
  79 {
  80     size_t n = 0;
  81     a_u16 value = 0;
  82     struct crc16 *const self = (struct crc16 *)JS_GetOpaque2(ctx, this_val, liba_crc16_class_id);
  83     if (!self) { return JS_EXCEPTION; }
  84     if (argc > 1)
  85     {
  86         a_u32 x = 0;
  87         if (JS_ToUint32(ctx, &x, argv[1])) { return JS_EXCEPTION; }
  88         value = (a_u16)x;
  89     }
  90     if (JS_IsArray(ctx, argv[0]))
  91     {
  92         a_byte *p = JS_GetArrayBuffer(ctx, &n, argv[0]);
  93         if (p) { value = self->eval(self->table, p, n, value); }
  94     }
  95     else
  96     {
  97         char const *const p = JS_ToCStringLen(ctx, &n, argv[0]);
  98         value = self->eval(self->table, p, n, value);
  99         JS_FreeCString(ctx, p);
 100     }
 101     return JS_NewUint32(ctx, value);
 102 }
 103
 104 static JSValue liba_crc16_pack(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
 105 {
 106     JSValue val = JS_UNDEFINED;
 107     a_u16 value = 0;
 108     size_t n = 0;
 109     char const *s;
 110     a_byte *p;
 111     struct crc16 *const self = (struct crc16 *)JS_GetOpaque2(ctx, this_val, liba_crc16_class_id);
 112     if (!self) { return JS_EXCEPTION; }
 113     if (argc > 1)
 114     {
 115         a_u32 x = 0;
 116         if (JS_ToUint32(ctx, &x, argv[1])) { return JS_EXCEPTION; }
 117         value = (a_u16)x;
 118     }
 119     s = JS_ToCStringLen(ctx, &n, argv[0]);
 120     value = self->eval(self->table, s, n, value);
 121     p = (a_byte *)js_malloc(ctx, n + 2);
 122     if (p) { a_copy(p, s, n); }
 123     else { goto fail; }
 124     self->eval == a_crc16m
 125         ? a_u16_setb(p + n, value)
 126         : a_u16_setl(p + n, value);
 127     val = js_array_u8_new(ctx, p, (uint32_t)n + 2);
 128 fail:
 129     JS_FreeCString(ctx, s);
 130     js_free(ctx, p);
 131     return val;
 132 }
 133
 134 static JSValue liba_crc16_get(JSContext *ctx, JSValueConst this_val)
 135 {
 136     struct crc16 *const self = (struct crc16 *)JS_GetOpaque2(ctx, this_val, liba_crc16_class_id);
 137     if (!self) { return JS_EXCEPTION; }
 138     return js_array_u16_new(ctx, self->table, 0x100);
 139 }
 140
 141 static JSClassDef liba_crc16_class;
 142 static JSCFunctionListEntry const liba_crc16_proto[] = {
 143     JS_PROP_STRING_DEF("[Symbol.toStringTag]", "a.crc16", 0),
 144     JS_CGETSET_DEF("table", liba_crc16_get, NULL),
 145     JS_CFUNC_DEF("gen", 2, liba_crc16_gen),
 146     JS_CFUNC_DEF("eval", 2, liba_crc16_eval),
 147     JS_CFUNC_DEF("pack", 2, liba_crc16_pack),
 148 };
 149
 150 int js_liba_crc16_init(JSContext *ctx, JSModuleDef *m)
 151 {
 152     JSValue proto, clazz;
 153     liba_crc16_class.class_name = "crc16";
 154     liba_crc16_class.finalizer = liba_crc16_finalizer;
 155
 156     JS_NewClassID(&liba_crc16_class_id);
 157     JS_NewClass(JS_GetRuntime(ctx), liba_crc16_class_id, &liba_crc16_class);
 158
 159     proto = JS_NewObject(ctx);
 160     JS_SetPropertyFunctionList(ctx, proto, liba_crc16_proto, A_LEN(liba_crc16_proto));
 161
 162     clazz = JS_NewCFunction2(ctx, liba_crc16_ctor, "crc16", 2, JS_CFUNC_constructor, 0);
 163     JS_SetClassProto(ctx, liba_crc16_class_id, proto);
 164     JS_SetConstructor(ctx, clazz, proto);
 165
 166     return JS_SetModuleExport(ctx, m, "crc16", clazz);
 167 }