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 JSValue liba_crc32_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 crc32 *const self = (struct crc32 *)js_mallocz(ctx, sizeof(struct crc32));
  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_crc32l_init(self->table, poly);
  33         self->eval = a_crc32l;
  34     }
  35     else
  36     {
  37         a_crc32m_init(self->table, poly);
  38         self->eval = a_crc32m;
  39     }
  40     proto = JS_GetPropertyStr(ctx, new_target, "prototype");
  41     if (JS_IsException(proto)) { goto fail; }
  42     clazz = JS_NewObjectProtoClass(ctx, proto, liba_crc32_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_crc32_gen(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
  54 {
  55     a_u32 poly = 0;
  56     int reversed = 0;
  57     struct crc32 *const self = (struct crc32 *)JS_GetOpaque2(ctx, this_val, liba_crc32_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_crc32l_init(self->table, poly);
  68         self->eval = a_crc32l;
  69     }
  70     else
  71     {
  72         a_crc32m_init(self->table, poly);
  73         self->eval = a_crc32m;
  74     }
  75     return JS_UNDEFINED;
  76 }
  77
  78 static JSValue liba_crc32_eval(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
  79 {
  80     size_t n = 0;
  81     a_u32 value = 0;
  82     struct crc32 *const self = (struct crc32 *)JS_GetOpaque2(ctx, this_val, liba_crc32_class_id);
  83     if (!self) { return JS_EXCEPTION; }
  84     if (argc > 1)
  85     {
  86         if (JS_ToUint32(ctx, &value, argv[1])) { return JS_EXCEPTION; }
  87     }
  88     if (JS_IsArray(ctx, argv[0]))
  89     {
  90         a_byte *p = JS_GetArrayBuffer(ctx, &n, argv[0]);
  91         if (p) { value = self->eval(self->table, p, n, value); }
  92     }
  93     else
  94     {
  95         char const *const p = JS_ToCStringLen(ctx, &n, argv[0]);
  96         value = self->eval(self->table, p, n, value);
  97         JS_FreeCString(ctx, p);
  98     }
  99     return JS_NewUint32(ctx, value);
 100 }
 101
 102 static JSValue liba_crc32_pack(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv)
 103 {
 104     JSValue val = JS_UNDEFINED;
 105     a_u32 value = 0;
 106     size_t n = 0;
 107     char const *s;
 108     a_byte *p;
 109     struct crc32 *const self = (struct crc32 *)JS_GetOpaque2(ctx, this_val, liba_crc32_class_id);
 110     if (!self) { return JS_EXCEPTION; }
 111     if (argc > 1)
 112     {
 113         if (JS_ToUint32(ctx, &value, argv[1])) { return JS_EXCEPTION; }
 114     }
 115     s = JS_ToCStringLen(ctx, &n, argv[0]);
 116     value = self->eval(self->table, s, n, value);
 117     p = (a_byte *)js_malloc(ctx, n + 4);
 118     if (p) { a_copy(p, s, n); }
 119     else { goto fail; }
 120     self->eval == a_crc32m
 121         ? a_u32_setb(p + n, value)
 122         : a_u32_setl(p + n, value);
 123     val = js_array_u8_new(ctx, p, (uint32_t)n + 4);
 124 fail:
 125     JS_FreeCString(ctx, s);
 126     js_free(ctx, p);
 127     return val;
 128 }
 129
 130 static JSValue liba_crc32_get(JSContext *ctx, JSValueConst this_val)
 131 {
 132     struct crc32 *const self = (struct crc32 *)JS_GetOpaque2(ctx, this_val, liba_crc32_class_id);
 133     if (!self) { return JS_EXCEPTION; }
 134     return js_array_u32_new(ctx, self->table, 0x100);
 135 }
 136
 137 static JSClassDef liba_crc32_class;
 138 static JSCFunctionListEntry const liba_crc32_proto[] = {
 139     JS_PROP_STRING_DEF("[Symbol.toStringTag]", "a.crc32", 0),
 140     JS_CGETSET_DEF("table", liba_crc32_get, NULL),
 141     JS_CFUNC_DEF("gen", 2, liba_crc32_gen),
 142     JS_CFUNC_DEF("eval", 2, liba_crc32_eval),
 143     JS_CFUNC_DEF("pack", 2, liba_crc32_pack),
 144 };
 145
 146 int js_liba_crc32_init(JSContext *ctx, JSModuleDef *m)
 147 {
 148     JSValue proto, clazz;
 149     liba_crc32_class.class_name = "crc32";
 150     liba_crc32_class.finalizer = liba_crc32_finalizer;
 151
 152     JS_NewClassID(&liba_crc32_class_id);
 153     JS_NewClass(JS_GetRuntime(ctx), liba_crc32_class_id, &liba_crc32_class);
 154
 155     proto = JS_NewObject(ctx);
 156     JS_SetPropertyFunctionList(ctx, proto, liba_crc32_proto, A_LEN(liba_crc32_proto));
 157
 158     clazz = JS_NewCFunction2(ctx, liba_crc32_ctor, "crc32", 2, JS_CFUNC_constructor, 0);
 159     JS_SetClassProto(ctx, liba_crc32_class_id, proto);
 160     JS_SetConstructor(ctx, clazz, proto);
 161
 162     return JS_SetModuleExport(ctx, m, "crc32", clazz);
 163 }