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Runtime error
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1fa8efd | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 | #define NAPI_VERSION 1
#include <assert.h>
#include <node_api.h>
napi_value Mask(napi_env env, napi_callback_info info) {
napi_status status;
size_t argc = 5;
napi_value argv[5];
status = napi_get_cb_info(env, info, &argc, argv, NULL, NULL);
assert(status == napi_ok);
uint8_t *source;
uint8_t *mask;
uint8_t *destination;
int64_t offset;
int64_t length;
status = napi_get_buffer_info(env, argv[0], (void **)&source, NULL);
assert(status == napi_ok);
status = napi_get_buffer_info(env, argv[1], (void **)&mask, NULL);
assert(status == napi_ok);
status = napi_get_buffer_info(env, argv[2], (void **)&destination, NULL);
assert(status == napi_ok);
status = napi_get_value_int64(env, argv[3], &offset);
assert(status == napi_ok);
status = napi_get_value_int64(env, argv[4], &length);
assert(status == napi_ok);
destination += offset;
uint8_t index = 0;
//
// Alignment preamble.
//
while (index < length && (size_t)source % 8) {
*destination++ = *source++ ^ mask[index % 4];
index++;
}
length -= index;
if (!length)
return NULL;
//
// Realign mask and convert to 64 bit.
//
uint8_t maskAlignedArray[8];
for (uint8_t i = 0; i < 8; i++, index++) {
maskAlignedArray[i] = mask[index % 4];
}
//
// Apply 64 bit mask in 8 byte chunks.
//
int64_t loop = length / 8;
uint64_t mask8 = ((uint64_t *)maskAlignedArray)[0];
uint64_t *pFrom8 = (uint64_t *)source;
uint64_t *pTo8 = (uint64_t *)destination;
for (int64_t i = 0; i < loop; i++) {
pTo8[i] = pFrom8[i] ^ mask8;
}
//
// Apply mask to remaining data.
//
length %= 8;
source += 8 * loop;
destination += 8 * loop;
for (uint8_t i = 0; i < length; i++) {
destination[i] = source[i] ^ maskAlignedArray[i];
}
return NULL;
}
napi_value Unmask(napi_env env, napi_callback_info info) {
napi_status status;
size_t argc = 2;
napi_value argv[2];
status = napi_get_cb_info(env, info, &argc, argv, NULL, NULL);
assert(status == napi_ok);
uint8_t *source;
uint8_t *mask;
size_t length;
status = napi_get_buffer_info(env, argv[0], (void **)&source, &length);
assert(status == napi_ok);
status = napi_get_buffer_info(env, argv[1], (void **)&mask, NULL);
assert(status == napi_ok);
uint8_t index = 0;
//
// Alignment preamble.
//
while (index < length && (size_t)source % 8) {
*source++ ^= mask[index % 4];
index++;
}
length -= index;
if (!length)
return NULL;
//
// Realign mask and convert to 64 bit.
//
uint8_t maskAlignedArray[8];
for (uint8_t i = 0; i < 8; i++, index++) {
maskAlignedArray[i] = mask[index % 4];
}
//
// Apply 64 bit mask in 8 byte chunks.
//
size_t loop = length / 8;
uint64_t mask8 = ((uint64_t *)maskAlignedArray)[0];
uint64_t *pSource8 = (uint64_t *)source;
for (size_t i = 0; i < loop; i++) {
pSource8[i] ^= mask8;
}
//
// Apply mask to remaining data.
//
length %= 8;
source += 8 * loop;
for (uint8_t i = 0; i < length; i++) {
source[i] ^= maskAlignedArray[i];
}
return NULL;
}
napi_value Init(napi_env env, napi_value exports) {
napi_status status;
napi_value mask;
napi_value unmask;
status = napi_create_function(env, NULL, 0, Mask, NULL, &mask);
assert(status == napi_ok);
status = napi_create_function(env, NULL, 0, Unmask, NULL, &unmask);
assert(status == napi_ok);
status = napi_set_named_property(env, exports, "mask", mask);
assert(status == napi_ok);
status = napi_set_named_property(env, exports, "unmask", unmask);
assert(status == napi_ok);
return exports;
}
NAPI_MODULE(NODE_GYP_MODULE_NAME, Init)
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