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_gen(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
  56 {
  57     struct crc16 *const self = (struct crc16 *)JS_GetOpaque2(ctx, this_val, liba_crc16_class_id);
  58     if (!self) { return JS_EXCEPTION; }
  59     a_u32 poly = 0;
  60     if (JS_ToUint32(ctx, &poly, argv[0])) { return JS_EXCEPTION; }
  61     int reversed = 0;
  62     if (argc > 1)
  63     {
  64         reversed = JS_ToBool(ctx, argv[1]);
  65         if (reversed < 0) { return JS_EXCEPTION; }
  66     }
  67     if (reversed)
  68     {
  69         a_crc16l_init(self->table, (a_u16)poly);
  70         self->eval = a_crc16l;
  71     }
  72     else
  73     {
  74         a_crc16m_init(self->table, (a_u16)poly);
  75         self->eval = a_crc16m;
  76     }
  77     return JS_UNDEFINED;
  78 }
  79
  80 static JSValue liba_crc16_eval(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
  81 {
  82     struct crc16 *const self = (struct crc16 *)JS_GetOpaque2(ctx, this_val, liba_crc16_class_id);
  83     if (!self) { return JS_EXCEPTION; }
  84     a_u16 value = 0;
  85     if (argc > 1)
  86     {
  87         a_u32 x = 0;
  88         if (JS_ToUint32(ctx, &x, argv[1])) { return JS_EXCEPTION; }
  89         value = (a_u16)x;
  90     }
  91     size_t n = 0;
  92     if (JS_IsArray(ctx, argv[0]))
  93     {
  94         a_byte *p = JS_GetArrayBuffer(ctx, &n, argv[0]);
  95         if (p) { value = self->eval(self->table, p, n, value); }
  96     }
  97     else
  98     {
  99         char const *const p = JS_ToCStringLen(ctx, &n, argv[0]);
 100         value = self->eval(self->table, p, n, value);
 101         JS_FreeCString(ctx, p);
 102     }
 103     return JS_NewUint32(ctx, value);
 104 }
 105
 106 static JSValue liba_crc16_pack(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
 107 {
 108     JSValue val = JS_UNDEFINED;
 109     struct crc16 *const self = (struct crc16 *)JS_GetOpaque2(ctx, this_val, liba_crc16_class_id);
 110     if (!self) { return JS_EXCEPTION; }
 111     a_u16 value = 0;
 112     if (argc > 1)
 113     {
 114         a_u32 x = 0;
 115         if (JS_ToUint32(ctx, &x, argv[1])) { return JS_EXCEPTION; }
 116         value = (a_u16)x;
 117     }
 118     size_t n = 0;
 119     char const *const s = JS_ToCStringLen(ctx, &n, argv[0]);
 120     value = self->eval(self->table, s, n, value);
 121     a_byte *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 enum
 135 {
 136     self_table_,
 137 };
 138
 139 static JSValue liba_crc16_get(JSContext *ctx, JSValueConst this_val, int magic)
 140 {
 141     struct crc16 *const self = (struct crc16 *)JS_GetOpaque2(ctx, this_val, liba_crc16_class_id);
 142     if (!self) { return JS_EXCEPTION; }
 143     if (magic == self_table_)
 144     {
 145         return js_array_u16_new(ctx, self->table, 0x100);
 146     }
 147     return JS_UNDEFINED;
 148 }
 149
 150 static JSCFunctionListEntry const liba_crc16_proto[] = {
 151     JS_PROP_STRING_DEF("[Symbol.toStringTag]", "a.crc16", 0),
 152     JS_CGETSET_MAGIC_DEF("table", liba_crc16_get, NULL, self_table_),
 153     JS_CFUNC_DEF("gen", 2, liba_crc16_gen),
 154     JS_CFUNC_DEF("eval", 2, liba_crc16_eval),
 155     JS_CFUNC_DEF("pack", 2, liba_crc16_pack),
 156 };
 157
 158 int js_liba_crc16_init(JSContext *ctx, JSModuleDef *m)
 159 {
 160     JS_NewClassID(&liba_crc16_class_id);
 161     JS_NewClass(JS_GetRuntime(ctx), liba_crc16_class_id, &liba_crc16_class);
 162
 163     JSValue const proto = JS_NewObject(ctx);
 164     JS_SetPropertyFunctionList(ctx, proto, liba_crc16_proto, A_LEN(liba_crc16_proto));
 165
 166     JSValue const clazz = JS_NewCFunction2(ctx, liba_crc16_ctor, "crc16", 2, JS_CFUNC_constructor, 0);
 167     JS_SetConstructor(ctx, clazz, proto);
 168     JS_SetClassProto(ctx, liba_crc16_class_id, proto);
 169
 170     return JS_SetModuleExport(ctx, m, "crc16", clazz);
 171 }