add base64 and base64url encoder/decoders

scripts/text.cm

@@ -411,5 +411,9 @@ function format_number(num, format) {
 }
 
 text.base32_to_blob = that.base32_to_blob
+text.base64_to_blob = that.base64_to_blob
+text.base64url_to_blob = that.base64url_to_blob
+text.blob_to_base64 = that.blob_to_base64
+text.blob_to_base64url = that.blob_to_base64url
 
 return text;

source/qjs_text.c

@@ -139,10 +139,165 @@ JSC_CCALL(text_base32_to_blob,
   return val;
 )
 
+static int base64_char_to_val_standard(char c) {
+  if (c >= 'A' && c <= 'Z') return c - 'A';
+  if (c >= 'a' && c <= 'z') return c - 'a' + 26;
+  if (c >= '0' && c <= '9') return c - '0' + 52;
+  if (c == '+') return 62;
+  if (c == '/') return 63;
+  return -1;
+}
+static int base64_char_to_val_url(char c) {
+  if (c >= 'A' && c <= 'Z') return c - 'A';
+  if (c >= 'a' && c <= 'z') return c - 'a' + 26;
+  if (c >= '0' && c <= '9') return c - '0' + 52;
+  if (c == '-') return 62;
+  if (c == '_') return 63;
+  return -1;
+}
+
+/*─── blob → Base64 (standard, with ‘+’ and ‘/’, padded) ───────────────────*/
+JSC_CCALL(text_blob_to_base64,
+  size_t blob_len;
+  void *blob_data = js_get_blob_data(js, &blob_len, argv[0]);
+  if (!blob_data) return JS_ThrowTypeError(js, "Expected stone blob");
+  const uint8_t *bytes = blob_data;
+  static const char b64[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+                            "abcdefghijklmnopqrstuvwxyz"
+                            "0123456789+/";
+  size_t out_len = ((blob_len + 2) / 3) * 4;
+  char *out = malloc(out_len + 1);
+  if (!out) return JS_ThrowOutOfMemory(js);
+
+  size_t in_i = 0, out_i = 0;
+  while (in_i < blob_len) {
+    uint32_t buf = 0;
+    int to_read = (blob_len - in_i < 3 ? blob_len - in_i : 3);
+    for (int j = 0; j < to_read; ++j) {
+      buf = (buf << 8) | bytes[in_i++];
+    }
+    buf <<= 8 * (3 - to_read);
+    out[out_i++] = b64[(buf >> 18) & 0x3F];
+    out[out_i++] = b64[(buf >> 12) & 0x3F];
+    out[out_i++] = (to_read > 1 ? b64[(buf >> 6) & 0x3F] : '=');
+    out[out_i++] = (to_read > 2 ? b64[ buf        & 0x3F] : '=');
+  }
+  out[out_len] = '\0';
+  JSValue v = JS_NewString(js, out);
+  free(out);
+  return v;
+)
+
+/*─── Base64 → blob (standard, expects ‘+’ and ‘/’, pads allowed) ────────────*/
+JSC_CCALL(text_base64_to_blob,
+  const char *str = JS_ToCString(js, argv[0]);
+  if (!str) return JS_ThrowTypeError(js, "Expected string");
+  size_t len = strlen(str);
+  // strip padding for length calculation
+  size_t eff = len;
+  while (eff > 0 && str[eff-1] == '=') eff--;
+  size_t out_len = (eff * 6) / 8;
+  uint8_t *out = malloc(out_len);
+  if (!out) { JS_FreeCString(js, str); return JS_ThrowOutOfMemory(js); }
+
+  size_t in_i = 0, out_i = 0;
+  while (in_i < eff) {
+    uint32_t buf = 0;
+    int to_read = (eff - in_i < 4 ? eff - in_i : 4);
+    for (int j = 0; j < to_read; ++j) {
+      int v = base64_char_to_val_standard(str[in_i++]);
+      if (v < 0) { free(out); JS_FreeCString(js, str);
+                   return JS_ThrowTypeError(js, "Invalid base64 character"); }
+      buf = (buf << 6) | v;
+    }
+    buf <<= 6 * (4 - to_read);
+    int bytes_out = (to_read * 6) / 8;
+    for (int j = 0; j < bytes_out && out_i < out_len; ++j) {
+      out[out_i++] = (buf >> (16 - 8*j)) & 0xFF;
+    }
+  }
+
+  JSValue v = js_new_blob_stoned_copy(js, out, out_len);
+  free(out);
+  JS_FreeCString(js, str);
+  return v;
+)
+
+/*─── blob → Base64URL (no padding, ‘-’ and ‘_’) ─────────────────────────────*/
+JSC_CCALL(text_blob_to_base64url,
+  size_t blob_len;
+  void *blob_data = js_get_blob_data(js, &blob_len, argv[0]);
+  if (!blob_data) return JS_ThrowTypeError(js, "Expected stone blob");
+  const uint8_t *bytes = blob_data;
+  static const char b64url[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+                               "abcdefghijklmnopqrstuvwxyz"
+                               "0123456789-_";
+  size_t raw_len = ((blob_len + 2) / 3) * 4;
+  // we’ll drop any trailing '='
+  char *out = malloc(raw_len + 1);
+  if (!out) return JS_ThrowOutOfMemory(js);
+
+  size_t in_i = 0, out_i = 0;
+  while (in_i < blob_len) {
+    uint32_t buf = 0;
+    int to_read = (blob_len - in_i < 3 ? blob_len - in_i : 3);
+    for (int j = 0; j < to_read; ++j) {
+      buf = (buf << 8) | bytes[in_i++];
+    }
+    buf <<= 8 * (3 - to_read);
+    out[out_i++] = b64url[(buf >> 18) & 0x3F];
+    out[out_i++] = b64url[(buf >> 12) & 0x3F];
+    if (to_read > 1) out[out_i++] = b64url[(buf >> 6) & 0x3F];
+    if (to_read > 2) out[out_i++] = b64url[ buf        & 0x3F];
+  }
+  out[out_i] = '\0';
+  JSValue v = JS_NewString(js, out);
+  free(out);
+  return v;
+)
+
+/*─── Base64URL → blob (accepts ‘-’ / ‘_’, no padding needed) ─────────────────*/
+JSC_CCALL(text_base64url_to_blob,
+  const char *str = JS_ToCString(js, argv[0]);
+  if (!str) return JS_ThrowTypeError(js, "Expected string");
+  size_t len = strlen(str);
+  size_t eff = len;  // no '=' in URL‐safe, but strip if present
+  while (eff > 0 && str[eff-1] == '=') eff--;
+  size_t out_len = (eff * 6) / 8;
+  uint8_t *out = malloc(out_len);
+  if (!out) { JS_FreeCString(js, str); return JS_ThrowOutOfMemory(js); }
+
+  size_t in_i = 0, out_i = 0;
+  while (in_i < eff) {
+    uint32_t buf = 0;
+    int to_read = (eff - in_i < 4 ? eff - in_i : 4);
+    for (int j = 0; j < to_read; ++j) {
+      int v = base64_char_to_val_url(str[in_i++]);
+      if (v < 0) { free(out); JS_FreeCString(js, str);
+                   return JS_ThrowTypeError(js, "Invalid base64url character"); }
+      buf = (buf << 6) | v;
+    }
+    buf <<= 6 * (4 - to_read);
+    int bytes_out = (to_read * 6) / 8;
+    for (int j = 0; j < bytes_out && out_i < out_len; ++j) {
+      out[out_i++] = (buf >> (16 - 8*j)) & 0xFF;
+    }
+  }
+
+  JSValue v = js_new_blob_stoned_copy(js, out, out_len);
+  free(out);
+  JS_FreeCString(js, str);
+  return v;
+)
+
 static const JSCFunctionListEntry js_text_funcs[] = {
   MIST_FUNC_DEF(text, blob_to_hex, 1),
   MIST_FUNC_DEF(text, blob_to_base32, 1),
   MIST_FUNC_DEF(text, base32_to_blob, 1),
+  MIST_FUNC_DEF(text, blob_to_base64,      1),
+  MIST_FUNC_DEF(text, base64_to_blob,      1),
+  MIST_FUNC_DEF(text, blob_to_base64url,   1),
+  MIST_FUNC_DEF(text, base64url_to_blob,   1),
 };
 
 JSValue js_text_use(JSContext *js)