src/SDL_error.c
author Ryan C. Gordon
Wed, 23 Nov 2016 11:49:26 -0500
changeset 10643 930938c7ca82
parent 10403 a0c76d344583
child 10644 594c17c446f6
permissions -rw-r--r--
Fixed more compiler warnings.
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
     4 
     5   This software is provided 'as-is', without any express or implied
     6   warranty.  In no event will the authors be held liable for any damages
     7   arising from the use of this software.
     8 
     9   Permission is granted to anyone to use this software for any purpose,
    10   including commercial applications, and to alter it and redistribute it
    11   freely, subject to the following restrictions:
    12 
    13   1. The origin of this software must not be misrepresented; you must not
    14      claim that you wrote the original software. If you use this software
    15      in a product, an acknowledgment in the product documentation would be
    16      appreciated but is not required.
    17   2. Altered source versions must be plainly marked as such, and must not be
    18      misrepresented as being the original software.
    19   3. This notice may not be removed or altered from any source distribution.
    20 */
    21 #include "./SDL_internal.h"
    22 
    23 /* Simple error handling in SDL */
    24 
    25 #include "SDL_log.h"
    26 #include "SDL_error.h"
    27 #include "SDL_error_c.h"
    28 
    29 
    30 /* Routine to get the thread-specific error variable */
    31 #if SDL_THREADS_DISABLED
    32 /* The default (non-thread-safe) global error variable */
    33 static SDL_error SDL_global_error;
    34 #define SDL_GetErrBuf() (&SDL_global_error)
    35 #else
    36 extern SDL_error *SDL_GetErrBuf(void);
    37 #endif /* SDL_THREADS_DISABLED */
    38 
    39 #define SDL_ERRBUFIZE   1024
    40 
    41 /* Private functions */
    42 
    43 static const char *
    44 SDL_LookupString(const char *key)
    45 {
    46     /* FIXME: Add code to lookup key in language string hash-table */
    47     return key;
    48 }
    49 
    50 /* Public functions */
    51 
    52 int
    53 SDL_SetError(SDL_PRINTF_FORMAT_STRING const char *fmt, ...)
    54 {
    55     va_list ap;
    56     SDL_error *error;
    57 
    58     /* Ignore call if invalid format pointer was passed */
    59     if (fmt == NULL) return -1;
    60 
    61     /* Copy in the key, mark error as valid */
    62     error = SDL_GetErrBuf();
    63     error->error = 1;
    64     SDL_strlcpy((char *) error->key, fmt, sizeof(error->key));
    65 
    66     va_start(ap, fmt);
    67     error->argc = 0;
    68     while (*fmt) {
    69         if (*fmt++ == '%') {
    70             while (*fmt == '.' || (*fmt >= '0' && *fmt <= '9')) {
    71                 ++fmt;
    72             }
    73             switch (*fmt++) {
    74             case 0:            /* Malformed format string.. */
    75                 --fmt;
    76                 break;
    77             case 'c':
    78             case 'i':
    79             case 'd':
    80             case 'u':
    81             case 'o':
    82             case 'x':
    83             case 'X':
    84                 error->args[error->argc++].value_i = va_arg(ap, int);
    85                 break;
    86             case 'f':
    87                 error->args[error->argc++].value_f = va_arg(ap, double);
    88                 break;
    89             case 'p':
    90                 error->args[error->argc++].value_ptr = va_arg(ap, void *);
    91                 break;
    92             case 's':
    93                 {
    94                     int i = error->argc;
    95                     const char *str = va_arg(ap, const char *);
    96                     if (str == NULL)
    97                         str = "(null)";
    98                     SDL_strlcpy((char *) error->args[i].buf, str,
    99                                 ERR_MAX_STRLEN);
   100                     error->argc++;
   101                 }
   102                 break;
   103             default:
   104                 break;
   105             }
   106             if (error->argc >= ERR_MAX_ARGS) {
   107                 break;
   108             }
   109         }
   110     }
   111     va_end(ap);
   112 
   113     /* If we are in debug mode, print out an error message */
   114     SDL_LogDebug(SDL_LOG_CATEGORY_ERROR, "%s", SDL_GetError());
   115 
   116     return -1;
   117 }
   118 
   119 static char *SDL_GetErrorMsg(char *errstr, int maxlen);
   120 
   121 /* Available for backwards compatibility */
   122 const char *
   123 SDL_GetError(void)
   124 {
   125     static char errmsg[SDL_ERRBUFIZE];
   126 
   127     return SDL_GetErrorMsg(errmsg, SDL_ERRBUFIZE);
   128 }
   129 
   130 void
   131 SDL_ClearError(void)
   132 {
   133     SDL_error *error;
   134 
   135     error = SDL_GetErrBuf();
   136     error->error = 0;
   137 }
   138 
   139 /* Very common errors go here */
   140 int
   141 SDL_Error(SDL_errorcode code)
   142 {
   143     switch (code) {
   144     case SDL_ENOMEM:
   145         return SDL_SetError("Out of memory");
   146     case SDL_EFREAD:
   147         return SDL_SetError("Error reading from datastream");
   148     case SDL_EFWRITE:
   149         return SDL_SetError("Error writing to datastream");
   150     case SDL_EFSEEK:
   151         return SDL_SetError("Error seeking in datastream");
   152     case SDL_UNSUPPORTED:
   153         return SDL_SetError("That operation is not supported");
   154     default:
   155         return SDL_SetError("Unknown SDL error");
   156     }
   157 }
   158 
   159 #ifdef TEST_ERROR
   160 int
   161 main(int argc, char *argv[])
   162 {
   163     char buffer[BUFSIZ + 1];
   164 
   165     SDL_SetError("Hi there!");
   166     printf("Error 1: %s\n", SDL_GetError());
   167     SDL_ClearError();
   168     SDL_memset(buffer, '1', BUFSIZ);
   169     buffer[BUFSIZ] = 0;
   170     SDL_SetError("This is the error: %s (%f)", buffer, 1.0);
   171     printf("Error 2: %s\n", SDL_GetError());
   172     exit(0);
   173 }
   174 #endif
   175 
   176 
   177 /* keep this at the end of the file so it works with GCC builds that don't
   178    support "#pragma GCC diagnostic push" ... we'll just leave the warning
   179    disabled after this. */
   180 #ifdef __GNUC__
   181 #pragma GCC diagnostic ignored "-Wformat-nonliteral"
   182 #endif
   183 /* This function has a bit more overhead than most error functions
   184    so that it supports internationalization and thread-safe errors.
   185 */
   186 static char *
   187 SDL_GetErrorMsg(char *errstr, int maxlen)
   188 {
   189     SDL_error *error;
   190 
   191     /* Clear the error string */
   192     *errstr = '\0';
   193     --maxlen;
   194 
   195     /* Get the thread-safe error, and print it out */
   196     error = SDL_GetErrBuf();
   197     if (error->error) {
   198         const char *fmt;
   199         char *msg = errstr;
   200         int len;
   201         int argi;
   202 
   203         fmt = SDL_LookupString(error->key);
   204         argi = 0;
   205         while (*fmt && (maxlen > 0)) {
   206             if (*fmt == '%') {
   207                 char tmp[32], *spot = tmp;
   208                 *spot++ = *fmt++;
   209                 while ((*fmt == '.' || (*fmt >= '0' && *fmt <= '9'))
   210                        && spot < (tmp + SDL_arraysize(tmp) - 2)) {
   211                     *spot++ = *fmt++;
   212                 }
   213                 *spot++ = *fmt++;
   214                 *spot++ = '\0';
   215                 switch (spot[-2]) {
   216                 case '%':
   217                     *msg++ = '%';
   218                     maxlen -= 1;
   219                     break;
   220                 case 'c':
   221                 case 'i':
   222                 case 'd':
   223                 case 'u':
   224                 case 'o':
   225                 case 'x':
   226                 case 'X':
   227                     len =
   228                         SDL_snprintf(msg, maxlen, tmp,
   229                                      error->args[argi++].value_i);
   230                     if (len > 0) {
   231                         msg += len;
   232                         maxlen -= len;
   233                     }
   234                     break;
   235 
   236                 case 'f':
   237                     len =
   238                         SDL_snprintf(msg, maxlen, tmp,
   239                                      error->args[argi++].value_f);
   240                     if (len > 0) {
   241                         msg += len;
   242                         maxlen -= len;
   243                     }
   244                     break;
   245 
   246                 case 'p':
   247                     len =
   248                         SDL_snprintf(msg, maxlen, tmp,
   249                                      error->args[argi++].value_ptr);
   250                     if (len > 0) {
   251                         msg += len;
   252                         maxlen -= len;
   253                     }
   254                     break;
   255 
   256                 case 's':
   257                     len =
   258                         SDL_snprintf(msg, maxlen, tmp,
   259                                      SDL_LookupString(error->args[argi++].
   260                                                       buf));
   261                     if (len > 0) {
   262                         msg += len;
   263                         maxlen -= len;
   264                     }
   265                     break;
   266 
   267                 }
   268             } else {
   269                 *msg++ = *fmt++;
   270                 maxlen -= 1;
   271             }
   272         }
   273 
   274         /* slide back if we've overshot the end of our buffer. */
   275         if (maxlen < 0) {
   276             msg -= (-maxlen) + 1;
   277         }
   278 
   279         *msg = 0;               /* NULL terminate the string */
   280     }
   281     return (errstr);
   282 }
   283 
   284 /* vi: set ts=4 sw=4 expandtab: */