xpcom/ds/nsCRT.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 /**
   8  * MODULE NOTES:
   9  * @update  gess7/30/98
  10  *
  11  * Much as I hate to do it, we were using string compares wrong.
  12  * Often, programmers call functions like strcmp(s1,s2), and pass
  13  * one or more null strings. Rather than blow up on these, I've
  14  * added quick checks to ensure that cases like this don't cause
  15  * us to fail.
  16  *
  17  * In general, if you pass a null into any of these string compare
  18  * routines, we simply return 0.
  19  */
  20
  21 #include "nsCRT.h"
  22 #include "nsDebug.h"
  23
  24 //----------------------------------------------------------------------
  25
  26 ////////////////////////////////////////////////////////////////////////////////
  27 // My lovely strtok routine
  28
  29 #define IS_DELIM(m, c) ((m)[(c) >> 3] & (1 << ((c)&7)))
  30 #define SET_DELIM(m, c) ((m)[(c) >> 3] |= (1 << ((c)&7)))
  31 #define DELIM_TABLE_SIZE 32
  32
  33 char* nsCRT::strtok(char* aString, const char* aDelims, char** aNewStr) {
  34   NS_ASSERTION(aString,
  35                "Unlike regular strtok, the first argument cannot be null.");
  36
  37   char delimTable[DELIM_TABLE_SIZE];
  38   uint32_t i;
  39   char* result;
  40   char* str = aString;
  41
  42   for (i = 0; i < DELIM_TABLE_SIZE; ++i) {
  43     delimTable[i] = '\0';
  44   }
  45
  46   for (i = 0; aDelims[i]; i++) {
  47     SET_DELIM(delimTable, static_cast<uint8_t>(aDelims[i]));
  48   }
  49   NS_ASSERTION(aDelims[i] == '\0', "too many delimiters");
  50
  51   // skip to beginning
  52   while (*str && IS_DELIM(delimTable, static_cast<uint8_t>(*str))) {
  53     str++;
  54   }
  55   result = str;
  56
  57   // fix up the end of the token
  58   while (*str) {
  59     if (IS_DELIM(delimTable, static_cast<uint8_t>(*str))) {
  60       *str++ = '\0';
  61       break;
  62     }
  63     str++;
  64   }
  65   *aNewStr = str;
  66
  67   return str == result ? nullptr : result;
  68 }
  69
  70 ////////////////////////////////////////////////////////////////////////////////
  71
  72 /**
  73  * Compare unichar string ptrs, stopping at the 1st null
  74  * NOTE: If both are null, we return 0.
  75  * NOTE: We terminate the search upon encountering a nullptr
  76  *
  77  * @update  gess 11/10/99
  78  * @param   s1 and s2 both point to unichar strings
  79  * @return  0 if they match, -1 if s1<s2; 1 if s1>s2
  80  */
  81 int32_t nsCRT::strcmp(const char16_t* aStr1, const char16_t* aStr2) {
  82   if (aStr1 && aStr2) {
  83     for (;;) {
  84       char16_t c1 = *aStr1++;
  85       char16_t c2 = *aStr2++;
  86       if (c1 != c2) {
  87         if (c1 < c2) {
  88           return -1;
  89         }
  90         return 1;
  91       }
  92       if (c1 == 0 || c2 == 0) {
  93         break;
  94       }
  95     }
  96   } else {
  97     if (aStr1) {  // aStr2 must have been null
  98       return -1;
  99     }
 100     if (aStr2) {  // aStr1 must have been null
 101       return 1;
 102     }
 103   }
 104   return 0;
 105 }
 106
 107 // This should use NSPR but NSPR isn't exporting its PR_strtoll function
 108 // Until then...
 109 int64_t nsCRT::atoll(const char* aStr) {
 110   if (!aStr) {
 111     return 0;
 112   }
 113
 114   int64_t ll = 0;
 115
 116   while (*aStr && *aStr >= '0' && *aStr <= '9') {
 117     ll *= 10;
 118     ll += *aStr - '0';
 119     aStr++;
 120   }
 121
 122   return ll;
 123 }