filter/error.c

   1 /*
   2  * "$Id$"
   3  *
   4  * Raster error handling for CUPS.
   5  *
   6  * Copyright 2007-2015 by Apple Inc.
   7  * Copyright 2007 by Easy Software Products.
   8  *
   9  * These coded instructions, statements, and computer programs are the
  10  * property of Apple Inc. and are protected by Federal copyright
  11  * law.  Distribution and use rights are outlined in the file "LICENSE.txt"
  12  * which should have been included with this file.  If this file is
  13  * file is missing or damaged, see the license at "http://www.cups.org/".
  14  *
  15  * This file is subject to the Apple OS-Developed Software exception.
  16  */
  17
  18 /*
  19  * Include necessary headers...
  20  */
  21
  22 #include <cups/raster-private.h>
  23
  24
  25 /*
  26  * Local structures...
  27  */
  28
  29 typedef struct _cups_raster_error_s     /**** Error buffer structure ****/
  30 {
  31   char  *start,                         /* Start of buffer */
  32         *current,                       /* Current position in buffer */
  33         *end;                           /* End of buffer */
  34 } _cups_raster_error_t;
  35
  36
  37 /*
  38  * Local functions...
  39  */
  40
  41 static _cups_raster_error_t     *get_error_buffer(void);
  42
  43
  44 /*
  45  * '_cupsRasterAddError()' - Add an error message to the error buffer.
  46  */
  47
  48 void
  49 _cupsRasterAddError(const char *f,      /* I - Printf-style error message */
  50                     ...)                /* I - Additional arguments as needed */
  51 {
  52   _cups_raster_error_t  *buf = get_error_buffer();
  53                                         /* Error buffer */
  54   va_list       ap;                     /* Pointer to additional arguments */
  55   char          s[2048];                /* Message string */
  56   ssize_t       bytes;                  /* Bytes in message string */
  57
  58
  59   DEBUG_printf(("_cupsRasterAddError(f=\"%s\", ...)", f));
  60
  61   va_start(ap, f);
  62   bytes = vsnprintf(s, sizeof(s), f, ap);
  63   va_end(ap);
  64
  65   if (bytes <= 0)
  66     return;
  67
  68   DEBUG_printf(("1_cupsRasterAddError: %s", s));
  69
  70   bytes ++;
  71
  72   if ((size_t)bytes >= sizeof(s))
  73     return;
  74
  75   if (bytes > (ssize_t)(buf->end - buf->current))
  76   {
  77    /*
  78     * Allocate more memory...
  79     */
  80
  81     char        *temp;                  /* New buffer */
  82     size_t      size;                   /* Size of buffer */
  83
  84
  85     size = (size_t)(buf->end - buf->start + 2 * bytes + 1024);
  86
  87     if (buf->start)
  88       temp = realloc(buf->start, size);
  89     else
  90       temp = malloc(size);
  91
  92     if (!temp)
  93       return;
  94
  95    /*
  96     * Update pointers...
  97     */
  98
  99     buf->end     = temp + size;
 100     buf->current = temp + (buf->current - buf->start);
 101     buf->start   = temp;
 102   }
 103
 104  /*
 105   * Append the message to the end of the current string...
 106   */
 107
 108   memcpy(buf->current, s, (size_t)bytes);
 109   buf->current += bytes - 1;
 110 }
 111
 112
 113 /*
 114  * '_cupsRasterClearError()' - Clear the error buffer.
 115  */
 116
 117 void
 118 _cupsRasterClearError(void)
 119 {
 120   _cups_raster_error_t  *buf = get_error_buffer();
 121                                         /* Error buffer */
 122
 123
 124   buf->current = buf->start;
 125
 126   if (buf->start)
 127     *(buf->start) = '\0';
 128 }
 129
 130
 131 /*
 132  * 'cupsRasterErrorString()' - Return the last error from a raster function.
 133  *
 134  * If there are no recent errors, NULL is returned.
 135  *
 136  * @since CUPS 1.3/OS X 10.5@
 137  */
 138
 139 const char *                            /* O - Last error */
 140 cupsRasterErrorString(void)
 141 {
 142   _cups_raster_error_t  *buf = get_error_buffer();
 143                                         /* Error buffer */
 144
 145
 146   if (buf->current == buf->start)
 147     return (NULL);
 148   else
 149     return (buf->start);
 150 }
 151
 152
 153 #ifdef HAVE_PTHREAD_H
 154 /*
 155  * Implement per-thread globals...
 156  */
 157
 158 #  include <pthread.h>
 159
 160
 161 /*
 162  * Local globals...
 163  */
 164
 165 static pthread_key_t    raster_key = 0; /* Thread local storage key */
 166 static pthread_once_t   raster_key_once = PTHREAD_ONCE_INIT;
 167                                         /* One-time initialization object */
 168
 169
 170 /*
 171  * Local functions...
 172  */
 173
 174 static void     raster_init(void);
 175 static void     raster_destructor(void *value);
 176
 177
 178 /*
 179  * 'get_error_buffer()' - Return a pointer to thread local storage.
 180  */
 181
 182 _cups_raster_error_t *                  /* O - Pointer to error buffer */
 183 get_error_buffer(void)
 184 {
 185   _cups_raster_error_t *buf;            /* Pointer to error buffer */
 186
 187
 188  /*
 189   * Initialize the global data exactly once...
 190   */
 191
 192   DEBUG_puts("3get_error_buffer()");
 193
 194   pthread_once(&raster_key_once, raster_init);
 195
 196  /*
 197   * See if we have allocated the data yet...
 198   */
 199
 200   if ((buf = (_cups_raster_error_t *)pthread_getspecific(raster_key))
 201           == NULL)
 202   {
 203     DEBUG_puts("4get_error_buffer: allocating memory for thread.");
 204
 205    /*
 206     * No, allocate memory as set the pointer for the key...
 207     */
 208
 209     buf = calloc(1, sizeof(_cups_raster_error_t));
 210     pthread_setspecific(raster_key, buf);
 211
 212     DEBUG_printf(("4get_error_buffer: buf=%p", buf));
 213   }
 214
 215  /*
 216   * Return the pointer to the data...
 217   */
 218
 219   return (buf);
 220 }
 221
 222
 223 /*
 224  * 'raster_init()' - Initialize error buffer once.
 225  */
 226
 227 static void
 228 raster_init(void)
 229 {
 230   pthread_key_create(&raster_key, raster_destructor);
 231
 232   DEBUG_printf(("3raster_init(): raster_key=%x(%u)", (unsigned)raster_key, (unsigned)raster_key));
 233 }
 234
 235
 236 /*
 237  * 'raster_destructor()' - Free memory allocated by get_error_buffer().
 238  */
 239
 240 static void
 241 raster_destructor(void *value)          /* I - Data to free */
 242 {
 243   _cups_raster_error_t *buf = (_cups_raster_error_t *)value;
 244                                         /* Error buffer */
 245
 246
 247   DEBUG_printf(("3raster_destructor(value=%p)", value));
 248
 249   if (buf->start)
 250     free(buf->start);
 251
 252   free(value);
 253 }
 254
 255
 256 #else
 257 /*
 258  * Implement static globals...
 259  */
 260
 261 /*
 262  * 'get_error_buffer()' - Return a pointer to thread local storage.
 263  */
 264
 265 _cups_raster_error_t *                  /* O - Pointer to error buffer */
 266 get_error_buffer(void)
 267 {
 268   static _cups_raster_error_t buf = { 0, 0, 0 };
 269                                         /* Error buffer */
 270
 271
 272   return (&buf);
 273 }
 274 #endif /* HAVE_PTHREAD_H */
 275
 276
 277 /*
 278  * End of "$Id$".
 279  */