granicus.if.org Git - imagemagick/blob - coders/fd.c

   1 /*
   2 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   3 %                                                                             %
   4 %                                                                             %
   5 %                                                                             %
   6 %                               FFFFF  DDDD                                   %
   7 %                               F      D   D                                  %
   8 %                               FFF    D   D                                  %
   9 %                               F      D   D                                  %
  10 %                               F      DDDD                                   %
  11 %                                                                             %
  12 %                                                                             %
  13 %                  Retrieve An Image Via a File Descriptor.                   %
  14 %                                                                             %
  15 %                              Software Design                                %
  16 %                                John Cristy                                  %
  17 %                              Bill Radcliffe                                 %
  18 %                                March 2000                                   %
  19 %                                                                             %
  20 %                                                                             %
  21 %  Copyright 1999-2013 ImageMagick Studio LLC, a non-profit organization      %
  22 %  dedicated to making software imaging solutions freely available.           %
  23 %                                                                             %
  24 %  You may not use this file except in compliance with the License.  You may  %
  25 %  obtain a copy of the License at                                            %
  26 %                                                                             %
  27 %    http://www.imagemagick.org/script/license.php                            %
  28 %                                                                             %
  29 %  Unless required by applicable law or agreed to in writing, software        %
  30 %  distributed under the License is distributed on an "AS IS" BASIS,          %
  31 %  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.   %
  32 %  See the License for the specific language governing permissions and        %
  33 %  limitations under the License.                                             %
  34 %                                                                             %
  35 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  36 %
  37 %
  38 */
  39 \f
  40 /*
  41   Include declarations.
  42 */
  43 #include "MagickCore/studio.h"
  44 #include "MagickCore/blob.h"
  45 #include "MagickCore/blob-private.h"
  46 #include "MagickCore/constitute.h"
  47 #include "MagickCore/exception.h"
  48 #include "MagickCore/exception-private.h"
  49 #include "MagickCore/image.h"
  50 #include "MagickCore/image-private.h"
  51 #include "MagickCore/list.h"
  52 #include "MagickCore/magick.h"
  53 #include "MagickCore/memory_.h"
  54 #include "MagickCore/module.h"
  55 #include "MagickCore/quantum-private.h"
  56 #include "MagickCore/static.h"
  57 #include "MagickCore/resource_.h"
  58 #include "MagickCore/string_.h"
  59 #include "MagickCore/string-private.h"
  60 #include "MagickCore/utility.h"
  61 \f
  62 /*
  63 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  64 %                                                                             %
  65 %                                                                             %
  66 %                                                                             %
  67 %   R e a d F D I m a g e                                                     %
  68 %                                                                             %
  69 %                                                                             %
  70 %                                                                             %
  71 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  72 %
  73 %  ReadFDImage retrieves an image via a file descriptor, decodes the image,
  74 %  and returns it.  It allocates the memory necessary for the new Image
  75 %  structure and returns a pointer to the new image.
  76 %
  77 %  The format of the ReadFDImage method is:
  78 %
  79 %      Image *ReadFDImage(const ImageInfo *image_info,ExceptionInfo *exception)
  80 %
  81 %  A description of each parameter follows:
  82 %
  83 %    o image_info: the image info.
  84 %
  85 %    o exception: return any errors or warnings in this structure.
  86 %
  87 */
  88 static Image *ReadFDImage(const ImageInfo *image_info,ExceptionInfo *exception)
  89 {
  90   Image
  91     *image;
  92
  93   ImageInfo
  94     *read_info;
  95
  96   /*
  97     Open image file.
  98   */
  99   assert(image_info != (const ImageInfo *) NULL);
 100   assert(image_info->signature == MagickSignature);
 101   if (image_info->debug != MagickFalse)
 102     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
 103       image_info->filename);
 104   assert(exception != (ExceptionInfo *) NULL);
 105   assert(exception->signature == MagickSignature);
 106   read_info=CloneImageInfo(image_info);
 107   read_info->file=fdopen(StringToLong(image_info->filename),"rb");
 108   if (read_info->file ==  (FILE *) NULL)
 109     {
 110       ThrowFileException(exception,BlobError,"UnableToOpenBlob",
 111         image_info->filename);
 112       return((Image *) NULL);
 113     }
 114   *read_info->magick='\0';
 115   image=ReadImage(read_info,exception);
 116   (void) fclose(read_info->file);
 117   read_info=DestroyImageInfo(read_info);
 118   if (image == (Image *) NULL)
 119     {
 120       (void) ThrowMagickException(exception,GetMagickModule(),CoderError,
 121         "NoDataReturned","`%s'",image_info->filename);
 122       return((Image *) NULL);
 123     }
 124   return(GetFirstImageInList(image));
 125 }
 126 \f
 127 /*
 128 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 129 %                                                                             %
 130 %                                                                             %
 131 %                                                                             %
 132 %   R e g i s t e r F D I m a g e                                             %
 133 %                                                                             %
 134 %                                                                             %
 135 %                                                                             %
 136 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 137 %
 138 %  RegisterFDImage() adds attributes for the FD image format to
 139 %  the list of supported formats.  The attributes include the image format
 140 %  tag, a method to read and/or write the format, whether the format
 141 %  supports the saving of more than one frame to the same file or blob,
 142 %  whether the format supports native in-memory I/O, and a brief
 143 %  description of the format.
 144 %
 145 %  The format of the RegisterFDImage method is:
 146 %
 147 %      size_t RegisterFDImage(void)
 148 %
 149 */
 150 ModuleExport size_t RegisterFDImage(void)
 151 {
 152   MagickInfo
 153     *entry;
 154
 155   entry=SetMagickInfo("FD");
 156   entry->decoder=(DecodeImageHandler *) ReadFDImage;
 157   entry->description=ConstantString("Read image from a file descriptor");
 158   entry->module=ConstantString("FD");
 159   entry->stealth=MagickTrue;
 160   (void) RegisterMagickInfo(entry);
 161   return(MagickImageCoderSignature);
 162 }
 163 \f
 164 /*
 165 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 166 %                                                                             %
 167 %                                                                             %
 168 %                                                                             %
 169 %   U n r e g i s t e r F D I m a g e                                         %
 170 %                                                                             %
 171 %                                                                             %
 172 %                                                                             %
 173 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 174 %
 175 %  UnregisterFDImage() removes format registrations made by the FD module from
 176 %  the list of supported formats.
 177 %
 178 %  The format of the UnregisterFDImage method is:
 179 %
 180 %      UnregisterFDImage(void)
 181 %
 182 */
 183 ModuleExport void UnregisterFDImage(void)
 184 {
 185   (void) UnregisterMagickInfo("FD");
 186 }