/*
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 

 #undef _GNU_SOURCE

 #define _XOPEN_SOURCE 600 /* XSI-compliant version of strerror_r */

 #include "avutil.h"
 #include "avstring.h"

 #include "common.h"

 struct error_entry {
     int num;
     const char *tag;
     const char *str;
 };
 
 #define ERROR_TAG(tag) AVERROR_##tag, #tag

 #define EERROR_TAG(tag) AVERROR(tag), #tag

 #define AVERROR_INPUT_AND_OUTPUT_CHANGED (AVERROR_INPUT_CHANGED | AVERROR_OUTPUT_CHANGED)

 static const struct error_entry error_entries[] = {

     { ERROR_TAG(BSF_NOT_FOUND),      "Bitstream filter not found"                     },
     { ERROR_TAG(BUG),                "Internal bug, should not have happened"         },
     { ERROR_TAG(BUG2),               "Internal bug, should not have happened"         },

     { ERROR_TAG(BUFFER_TOO_SMALL),   "Buffer too small"                               },

     { ERROR_TAG(DECODER_NOT_FOUND),  "Decoder not found"                              },
     { ERROR_TAG(DEMUXER_NOT_FOUND),  "Demuxer not found"                              },
     { ERROR_TAG(ENCODER_NOT_FOUND),  "Encoder not found"                              },
     { ERROR_TAG(EOF),                "End of file"                                    },
     { ERROR_TAG(EXIT),               "Immediate exit requested"                       },

     { ERROR_TAG(EXTERNAL),           "Generic error in an external library"           },

     { ERROR_TAG(FILTER_NOT_FOUND),   "Filter not found"                               },

     { ERROR_TAG(INPUT_CHANGED),      "Input changed"                                  },

     { ERROR_TAG(INVALIDDATA),        "Invalid data found when processing input"       },
     { ERROR_TAG(MUXER_NOT_FOUND),    "Muxer not found"                                },
     { ERROR_TAG(OPTION_NOT_FOUND),   "Option not found"                               },

     { ERROR_TAG(OUTPUT_CHANGED),     "Output changed"                                 },

     { ERROR_TAG(PATCHWELCOME),       "Not yet implemented in FFmpeg, patches welcome" },
     { ERROR_TAG(PROTOCOL_NOT_FOUND), "Protocol not found"                             },
     { ERROR_TAG(STREAM_NOT_FOUND),   "Stream not found"                               },
     { ERROR_TAG(UNKNOWN),            "Unknown error occurred"                         },

     { ERROR_TAG(EXPERIMENTAL),       "Experimental feature"                           },

     { ERROR_TAG(INPUT_AND_OUTPUT_CHANGED), "Input and output changed"                 },

     { ERROR_TAG(HTTP_BAD_REQUEST),   "Server returned 400 Bad Request"         },
     { ERROR_TAG(HTTP_UNAUTHORIZED),  "Server returned 401 Unauthorized (authorization failed)" },
     { ERROR_TAG(HTTP_FORBIDDEN),     "Server returned 403 Forbidden (access denied)" },
     { ERROR_TAG(HTTP_NOT_FOUND),     "Server returned 404 Not Found"           },
     { ERROR_TAG(HTTP_OTHER_4XX),     "Server returned 4XX Client Error, but not one of 40{0,1,3,4}" },
     { ERROR_TAG(HTTP_SERVER_ERROR),  "Server returned 5XX Server Error reply" },

 #if !HAVE_STRERROR_R

     { EERROR_TAG(E2BIG),             "Argument list too long" },
     { EERROR_TAG(EACCES),            "Permission denied" },
     { EERROR_TAG(EAGAIN),            "Resource temporarily unavailable" },
     { EERROR_TAG(EBADF),             "Bad file descriptor" },
     { EERROR_TAG(EBUSY),             "Device or resource busy" },
     { EERROR_TAG(ECHILD),            "No child processes" },
     { EERROR_TAG(EDEADLK),           "Resource deadlock avoided" },
     { EERROR_TAG(EDOM),              "Numerical argument out of domain" },
     { EERROR_TAG(EEXIST),            "File exists" },
     { EERROR_TAG(EFAULT),            "Bad address" },
     { EERROR_TAG(EFBIG),             "File too large" },
     { EERROR_TAG(EILSEQ),            "Illegal byte sequence" },
     { EERROR_TAG(EINTR),             "Interrupted system call" },

     { EERROR_TAG(EINVAL),            "Invalid argument" },

     { EERROR_TAG(EIO),               "I/O error" },
     { EERROR_TAG(EISDIR),            "Is a directory" },
     { EERROR_TAG(EMFILE),            "Too many open files" },
     { EERROR_TAG(EMLINK),            "Too many links" },
     { EERROR_TAG(ENAMETOOLONG),      "File name too long" },
     { EERROR_TAG(ENFILE),            "Too many open files in system" },
     { EERROR_TAG(ENODEV),            "No such device" },
     { EERROR_TAG(ENOENT),            "No such file or directory" },
     { EERROR_TAG(ENOEXEC),           "Exec format error" },
     { EERROR_TAG(ENOLCK),            "No locks available" },
     { EERROR_TAG(ENOMEM),            "Cannot allocate memory" },
     { EERROR_TAG(ENOSPC),            "No space left on device" },
     { EERROR_TAG(ENOSYS),            "Function not implemented" },
     { EERROR_TAG(ENOTDIR),           "Not a directory" },
     { EERROR_TAG(ENOTEMPTY),         "Directory not empty" },
     { EERROR_TAG(ENOTTY),            "Inappropriate I/O control operation" },
     { EERROR_TAG(ENXIO),             "No such device or address" },
     { EERROR_TAG(EPERM),             "Operation not permitted" },
     { EERROR_TAG(EPIPE),             "Broken pipe" },
     { EERROR_TAG(ERANGE),            "Result too large" },
     { EERROR_TAG(EROFS),             "Read-only file system" },
     { EERROR_TAG(ESPIPE),            "Illegal seek" },
     { EERROR_TAG(ESRCH),             "No such process" },
     { EERROR_TAG(EXDEV),             "Cross-device link" },

 #endif

 };
 

 int av_strerror(int errnum, char *errbuf, size_t errbuf_size)
 {

     int ret = 0, i;

     const struct error_entry *entry = NULL;

     for (i = 0; i < FF_ARRAY_ELEMS(error_entries); i++) {
         if (errnum == error_entries[i].num) {
             entry = &error_entries[i];
             break;
         }
     }
     if (entry) {
         av_strlcpy(errbuf, entry->str, errbuf_size);

     } else {
 #if HAVE_STRERROR_R

         ret = AVERROR(strerror_r(AVUNERROR(errnum), errbuf, errbuf_size));

 #else
         ret = -1;

 #endif

         if (ret < 0)

             snprintf(errbuf, errbuf_size, "Error number %d occurred", errnum);

     }
 
     return ret;
 }