src/SDL_error.c
author Ethan Lee <flibitijibibo@flibitijibibo.com>
Wed, 17 Jul 2019 23:20:57 -0400
changeset 12950 05dddfb66b85
parent 12642 8a70b87401c3
permissions -rw-r--r--
Copypaste SDL_NSLog to UIKit backend, document it as such
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2019 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 static char *SDL_GetErrorMsg(char *errstr, int maxlen);
    53 
    54 int
    55 SDL_SetError(SDL_PRINTF_FORMAT_STRING const char *fmt, ...)
    56 {
    57     va_list ap;
    58     SDL_error *error;
    59 
    60     /* Ignore call if invalid format pointer was passed */
    61     if (fmt == NULL) return -1;
    62 
    63     /* Copy in the key, mark error as valid */
    64     error = SDL_GetErrBuf();
    65     error->error = 1;
    66     SDL_strlcpy((char *) error->key, fmt, sizeof(error->key));
    67 
    68     va_start(ap, fmt);
    69     error->argc = 0;
    70     while (*fmt) {
    71         if (*fmt++ == '%') {
    72             while (*fmt == '.' || (*fmt >= '0' && *fmt <= '9')) {
    73                 ++fmt;
    74             }
    75             switch (*fmt++) {
    76             case 0:            /* Malformed format string.. */
    77                 --fmt;
    78                 break;
    79             case 'l':
    80                 switch (*fmt++) {
    81                 case 0:        /* Malformed format string.. */
    82                     --fmt;
    83                     break;
    84                 case 'i': case 'd': case 'u': case 'x': case 'X':
    85                     error->args[error->argc++].value_l = va_arg(ap, long);
    86                     break;
    87                 }
    88                 break;
    89             case 'c':
    90             case 'i':
    91             case 'd':
    92             case 'u':
    93             case 'o':
    94             case 'x':
    95             case 'X':
    96                 error->args[error->argc++].value_i = va_arg(ap, int);
    97                 break;
    98             case 'f':
    99                 error->args[error->argc++].value_f = va_arg(ap, double);
   100                 break;
   101             case 'p':
   102                 error->args[error->argc++].value_ptr = va_arg(ap, void *);
   103                 break;
   104             case 's':
   105                 {
   106                     int i = error->argc;
   107                     const char *str = va_arg(ap, const char *);
   108                     if (str == NULL)
   109                         str = "(null)";
   110                     SDL_strlcpy((char *) error->args[i].buf, str,
   111                                 ERR_MAX_STRLEN);
   112                     error->argc++;
   113                 }
   114                 break;
   115             default:
   116                 break;
   117             }
   118             if (error->argc >= ERR_MAX_ARGS) {
   119                 break;
   120             }
   121         }
   122     }
   123     va_end(ap);
   124 
   125     if (SDL_LogGetPriority(SDL_LOG_CATEGORY_ERROR) <= SDL_LOG_PRIORITY_DEBUG) {
   126         /* If we are in debug mode, print out an error message
   127          * Avoid stomping on the static buffer in GetError, just
   128          * in case this is called while processing a ShowMessageBox to
   129          * show an error already in that static buffer.
   130          */
   131         char errmsg[SDL_ERRBUFIZE];
   132         SDL_GetErrorMsg(errmsg, sizeof(errmsg));
   133         SDL_LogDebug(SDL_LOG_CATEGORY_ERROR, "%s", errmsg);
   134     }
   135     return -1;
   136 }
   137 
   138 /* Available for backwards compatibility */
   139 const char *
   140 SDL_GetError(void)
   141 {
   142     static char errmsg[SDL_ERRBUFIZE];
   143 
   144     return SDL_GetErrorMsg(errmsg, SDL_ERRBUFIZE);
   145 }
   146 
   147 void
   148 SDL_ClearError(void)
   149 {
   150     SDL_error *error;
   151 
   152     error = SDL_GetErrBuf();
   153     error->error = 0;
   154 }
   155 
   156 /* Very common errors go here */
   157 int
   158 SDL_Error(SDL_errorcode code)
   159 {
   160     switch (code) {
   161     case SDL_ENOMEM:
   162         return SDL_SetError("Out of memory");
   163     case SDL_EFREAD:
   164         return SDL_SetError("Error reading from datastream");
   165     case SDL_EFWRITE:
   166         return SDL_SetError("Error writing to datastream");
   167     case SDL_EFSEEK:
   168         return SDL_SetError("Error seeking in datastream");
   169     case SDL_UNSUPPORTED:
   170         return SDL_SetError("That operation is not supported");
   171     default:
   172         return SDL_SetError("Unknown SDL error");
   173     }
   174 }
   175 
   176 #ifdef TEST_ERROR
   177 int
   178 main(int argc, char *argv[])
   179 {
   180     char buffer[BUFSIZ + 1];
   181 
   182     SDL_SetError("Hi there!");
   183     printf("Error 1: %s\n", SDL_GetError());
   184     SDL_ClearError();
   185     SDL_memset(buffer, '1', BUFSIZ);
   186     buffer[BUFSIZ] = 0;
   187     SDL_SetError("This is the error: %s (%f)", buffer, 1.0);
   188     printf("Error 2: %s\n", SDL_GetError());
   189     exit(0);
   190 }
   191 #endif
   192 
   193 
   194 /* keep this at the end of the file so it works with GCC builds that don't
   195    support "#pragma GCC diagnostic push" ... we'll just leave the warning
   196    disabled after this. */
   197 /* this pragma arrived in GCC 4.2 and causes a warning on older GCCs! Sigh. */
   198 #if defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 4) || (__GNUC__ == 4 && (__GNUC_MINOR__ >= 2))))
   199 #pragma GCC diagnostic ignored "-Wformat-nonliteral"
   200 #endif
   201 
   202 /* This function has a bit more overhead than most error functions
   203    so that it supports internationalization and thread-safe errors.
   204 */
   205 static char *
   206 SDL_GetErrorMsg(char *errstr, int maxlen)
   207 {
   208     SDL_error *error;
   209 
   210     /* Clear the error string */
   211     *errstr = '\0';
   212     --maxlen;
   213 
   214     /* Get the thread-safe error, and print it out */
   215     error = SDL_GetErrBuf();
   216     if (error->error) {
   217         const char *fmt;
   218         char *msg = errstr;
   219         int len;
   220         int argi;
   221 
   222         fmt = SDL_LookupString(error->key);
   223         argi = 0;
   224         while (*fmt && (maxlen > 0)) {
   225             if (*fmt == '%') {
   226                 char tmp[32], *spot = tmp;
   227                 *spot++ = *fmt++;
   228                 while ((*fmt == '.' || (*fmt >= '0' && *fmt <= '9'))
   229                        && spot < (tmp + SDL_arraysize(tmp) - 2)) {
   230                     *spot++ = *fmt++;
   231                 }
   232                 if (*fmt == 'l') {
   233                     *spot++ = *fmt++;
   234                     *spot++ = *fmt++;
   235                     *spot++ = '\0';
   236                     switch (spot[-2]) {
   237                     case 'i': case 'd': case 'u': case 'x': case 'X':
   238                       len = SDL_snprintf(msg, maxlen, tmp,
   239                                          error->args[argi++].value_l);
   240                       if (len > 0) {
   241                           msg += len;
   242                           maxlen -= len;
   243                       }
   244                       break;
   245                     }
   246                     continue;
   247                 }
   248                 *spot++ = *fmt++;
   249                 *spot++ = '\0';
   250                 switch (spot[-2]) {
   251                 case '%':
   252                     *msg++ = '%';
   253                     maxlen -= 1;
   254                     break;
   255                 case 'c':
   256                 case 'i':
   257                 case 'd':
   258                 case 'u':
   259                 case 'o':
   260                 case 'x':
   261                 case 'X':
   262                     len =
   263                         SDL_snprintf(msg, maxlen, tmp,
   264                                      error->args[argi++].value_i);
   265                     if (len > 0) {
   266                         msg += len;
   267                         maxlen -= len;
   268                     }
   269                     break;
   270 
   271                 case 'f':
   272                     len =
   273                         SDL_snprintf(msg, maxlen, tmp,
   274                                      error->args[argi++].value_f);
   275                     if (len > 0) {
   276                         msg += len;
   277                         maxlen -= len;
   278                     }
   279                     break;
   280 
   281                 case 'p':
   282                     len =
   283                         SDL_snprintf(msg, maxlen, tmp,
   284                                      error->args[argi++].value_ptr);
   285                     if (len > 0) {
   286                         msg += len;
   287                         maxlen -= len;
   288                     }
   289                     break;
   290 
   291                 case 's':
   292                     len =
   293                         SDL_snprintf(msg, maxlen, tmp,
   294                                      SDL_LookupString(error->args[argi++].
   295                                                       buf));
   296                     if (len > 0) {
   297                         msg += len;
   298                         maxlen -= len;
   299                     }
   300                     break;
   301 
   302                 }
   303             } else {
   304                 *msg++ = *fmt++;
   305                 maxlen -= 1;
   306             }
   307         }
   308 
   309         /* slide back if we've overshot the end of our buffer. */
   310         if (maxlen < 0) {
   311             msg -= (-maxlen) + 1;
   312         }
   313 
   314         *msg = 0;               /* NULL terminate the string */
   315     }
   316     return (errstr);
   317 }
   318 
   319 /* vi: set ts=4 sw=4 expandtab: */