text: // Copyright 2016 The Chromium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #include "net/third_party/quiche/src/http2/tools/random_util.h"
  
  #include <cmath>
  
  namespace http2 {
  namespace test {
  
  // Here "word" means something that starts with a lower-case letter, and has
  // zero or more additional characters that are numbers or lower-case letters.
  Http2String GenerateHttp2HeaderName(size_t len, Http2Random* rng) {
    Http2StringPiece alpha_lc = "abcdefghijklmnopqrstuvwxyz";
    // If the name is short, just make it one word.
    if (len < 8) {
      return rng->RandStringWithAlphabet(len, alpha_lc);
    }
    // If the name is longer, ensure it starts with a word, and after that may
    // have any character in alphanumdash_lc. 4 is arbitrary, could be as low
    // as 1.
    Http2StringPiece alphanumdash_lc = "abcdefghijklmnopqrstuvwxyz0123456789-";
    return rng->RandStringWithAlphabet(4, alpha_lc) +
           rng->RandStringWithAlphabet(len - 4, alphanumdash_lc);
  }
  
  Http2String GenerateWebSafeString(size_t len, Http2Random* rng) {
    static const char* kWebsafe64 =
        "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-_";
    return rng->RandStringWithAlphabet(len, kWebsafe64);
  }
  
  Http2String GenerateWebSafeString(size_t lo, size_t hi, Http2Random* rng) {
    return GenerateWebSafeString(rng->UniformInRange(lo, hi), rng);
  }
  
  }  // namespace test
  }  // namespace http2
  