Line data    Source code

       1             : /*
       2             :  *
       3             :  *    Copyright (c) 2020 Project CHIP Authors
       4             :  *    Copyright (c) 2013-2017 Nest Labs, Inc.
       5             :  *
       6             :  *    Licensed under the Apache License, Version 2.0 (the "License");
       7             :  *    you may not use this file except in compliance with the License.
       8             :  *    You may obtain a copy of the License at
       9             :  *
      10             :  *        http://www.apache.org/licenses/LICENSE-2.0
      11             :  *
      12             :  *    Unless required by applicable law or agreed to in writing, software
      13             :  *    distributed under the License is distributed on an "AS IS" BASIS,
      14             :  *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
      15             :  *    See the License for the specific language governing permissions and
      16             :  *    limitations under the License.
      17             :  */
      18             : #include <lib/core/ErrorStr.h>
      19             : 
      20             : #ifndef __STDC_FORMAT_MACROS
      21             : #define __STDC_FORMAT_MACROS
      22             : #endif
      23             : 
      24             : #include <lib/core/CHIPConfig.h>
      25             : #include <lib/core/CHIPError.h>
      26             : #include <lib/support/DLLUtil.h>
      27             : 
      28             : #include <inttypes.h>
      29             : #include <stdio.h>
      30             : 
      31             : namespace chip {
      32             : 
      33             : /**
      34             :  * Static buffer to store the formatted error string.
      35             :  */
      36             : static char sErrorStr[CHIP_CONFIG_ERROR_STR_SIZE];
      37             : 
      38             : /**
      39             :  * Linked-list of error formatter functions.
      40             :  */
      41             : static ErrorFormatter * sErrorFormatterList = nullptr;
      42             : 
      43             : /**
      44             :  * This routine returns a human-readable NULL-terminated C string
      45             :  * describing the provided error.
      46             :  *
      47             :  * @param[in] err                      The error for format and describe.
      48             :  *
      49             :  * @return A pointer to a NULL-terminated C string describing the
      50             :  *         provided error.
      51             :  */
      52        3138 : DLL_EXPORT const char * ErrorStr(CHIP_ERROR err)
      53             : {
      54        3138 :     char * formattedError   = sErrorStr;
      55        3138 :     uint16_t formattedSpace = sizeof(sErrorStr);
      56             : 
      57             : #if CHIP_CONFIG_ERROR_SOURCE && !CHIP_CONFIG_SHORT_ERROR_STR
      58             : 
      59        3138 :     const char * const file = err.GetFile();
      60        3138 :     if (file != nullptr)
      61             :     {
      62        3123 :         int n = snprintf(formattedError, formattedSpace, "%s:%u: ", file, err.GetLine());
      63        3123 :         if (n > formattedSpace)
      64             :         {
      65           0 :             n = formattedSpace;
      66             :         }
      67        3123 :         formattedError += n;
      68        3123 :         formattedSpace = static_cast<uint16_t>(formattedSpace - n);
      69             :     }
      70        3138 :     if (err == CHIP_NO_ERROR)
      71             :     {
      72        2446 :         (void) snprintf(formattedError, formattedSpace, CHIP_NO_ERROR_STRING);
      73        2446 :         return sErrorStr;
      74             :     }
      75             : 
      76             : #else // CHIP_CONFIG_ERROR_SOURCE && !CHIP_CONFIG_SHORT_ERROR_STR
      77             : 
      78             :     if (err == CHIP_NO_ERROR)
      79             :     {
      80             :         return CHIP_NO_ERROR_STRING;
      81             :     }
      82             : 
      83             : #endif // CHIP_CONFIG_ERROR_SOURCE && !CHIP_CONFIG_SHORT_ERROR_STR
      84             : 
      85             :     // Search the registered error formatter for one that will format the given
      86             :     // error code.
      87        2054 :     for (const ErrorFormatter * errFormatter = sErrorFormatterList; errFormatter != nullptr; errFormatter = errFormatter->Next)
      88             :     {
      89        1977 :         if (errFormatter->FormatError(formattedError, formattedSpace, err))
      90             :         {
      91         615 :             return sErrorStr;
      92             :         }
      93             :     }
      94             : 
      95             :     // Use a default formatting if no formatter found.
      96          77 :     FormatError(formattedError, formattedSpace, nullptr, err, nullptr);
      97          77 :     return sErrorStr;
      98             : }
      99             : 
     100             : /**
     101             :  * Add a new error formatter function to the global list of error formatters.
     102             :  *
     103             :  * @param[in] errFormatter             An ErrorFormatter structure containing a
     104             :  *                                     pointer to the new error function.  Note
     105             :  *                                     that a pointer to the supplied ErrorFormatter
     106             :  *                                     structure will be retained by the function.
     107             :  *                                     Thus the memory for the structure must
     108             :  *                                     remain reserved.
     109             :  */
     110         692 : DLL_EXPORT void RegisterErrorFormatter(ErrorFormatter * errFormatter)
     111             : {
     112             :     // Do nothing if a formatter with the same format function is already in the list.
     113        1379 :     for (ErrorFormatter * existingFormatter = sErrorFormatterList; existingFormatter != nullptr;
     114         687 :          existingFormatter                  = existingFormatter->Next)
     115             :     {
     116        1152 :         if (existingFormatter->FormatError == errFormatter->FormatError)
     117             :         {
     118         465 :             return;
     119             :         }
     120             :     }
     121             : 
     122             :     // Add the formatter to the global list.
     123         227 :     errFormatter->Next  = sErrorFormatterList;
     124         227 :     sErrorFormatterList = errFormatter;
     125             : }
     126             : 
     127             : /**
     128             :  * Remove an error formatter function from the global list of error formatters.
     129             :  *
     130             :  * @param[in] errFormatter             An ErrorFormatter structure containing a
     131             :  *                                     pointer to the new error function.
     132             :  */
     133           2 : DLL_EXPORT void DeregisterErrorFormatter(ErrorFormatter * errFormatter)
     134             : {
     135             :     // Remove the formatter if present
     136           6 :     for (ErrorFormatter ** lfp = &sErrorFormatterList; *lfp != nullptr; lfp = &(*lfp)->Next)
     137             :     {
     138             :         // Remove the formatter from the global list, if found.
     139           4 :         if (*lfp == errFormatter)
     140             :         {
     141           1 :             *lfp = errFormatter->Next;
     142             :         }
     143             :     }
     144           2 : }
     145             : 
     146             : #if !CHIP_CONFIG_CUSTOM_ERROR_FORMATTER
     147             : 
     148             : /**
     149             :  * Generates a human-readable NULL-terminated C string describing the provided error.
     150             :  *
     151             :  * @param[in] buf                   Buffer into which the error string will be placed.
     152             :  * @param[in] bufSize               Size of the supplied buffer in bytes.
     153             :  * @param[in] subsys                A short string describing the subsystem that originated
     154             :  *                                  the error, or NULL if the origin of the error is
     155             :  *                                  unknown/unavailable.  This string should be 10
     156             :  *                                  characters or less.
     157             :  * @param[in] err                   The error to be formatted.
     158             :  * @param[in] desc                  A string describing the cause or meaning of the error,
     159             :  *                                  or NULL if no such information is available.
     160             :  */
     161         697 : DLL_EXPORT void FormatError(char * buf, uint16_t bufSize, const char * subsys, CHIP_ERROR err, const char * desc)
     162             : {
     163             : #if CHIP_CONFIG_SHORT_ERROR_STR
     164             : 
     165             :     if (subsys == nullptr)
     166             :     {
     167             :         (void) snprintf(buf, bufSize, "Error " CHIP_CONFIG_SHORT_FORM_ERROR_VALUE_FORMAT, err.AsInteger());
     168             :     }
     169             :     else
     170             :     {
     171             :         (void) snprintf(buf, bufSize, "Error %s:" CHIP_CONFIG_SHORT_FORM_ERROR_VALUE_FORMAT, subsys, err.AsInteger());
     172             :     }
     173             : 
     174             : #else // CHIP_CONFIG_SHORT_ERROR_STR
     175             : 
     176         697 :     const char * subsysSep = " ";
     177         697 :     const char * descSep   = ": ";
     178             : 
     179         697 :     if (subsys == nullptr)
     180             :     {
     181          79 :         subsys    = "";
     182          79 :         subsysSep = "";
     183             :     }
     184         697 :     if (desc == nullptr)
     185             :     {
     186          79 :         desc    = "";
     187          79 :         descSep = "";
     188             :     }
     189             : 
     190         697 :     (void) snprintf(buf, bufSize, "%s%sError 0x%08" PRIX32 "%s%s", subsys, subsysSep, err.AsInteger(), descSep, desc);
     191             : 
     192             : #endif // CHIP_CONFIG_SHORT_ERROR_STR
     193         697 : }
     194             : 
     195             : #endif // CHIP_CONFIG_CUSTOM_ERROR_FORMATTER
     196             : 
     197             : } // namespace chip