1 /*
2 * in_gif.cpp -- read a Compuserve GIF file
3 * by pts@fazekas.hu at Fri Mar 1 22:28:46 CET 2002
4 *
5 */
6
7 /*The creators of the GIF format require the following
8 acknowledgement:
9 The Graphics Interchange Format(c) is the Copyright property of
10 CompuServe Incorporated. GIF(sm) is a Service Mark property of
11 CompuServe Incorporated.
12 */
13
14 #ifdef __GNUC__
15 #ifndef __clang__
16 #pragma implementation
17 #endif
18 #endif
19
20 #ifdef USE_GNU_SOURCE_INSTEAD_OF_POSIX_SOURCE
21 #define _GNU_SOURCE 1 /* Implies _POSIX_C_SOURCE and _POSIX_C_SOURCE >= 2. */
22 #else
23 #define _POSIX_SOURCE 1
24 #define _POSIX_C_SOURCE 2
25 #endif
26
27 #include "config2.h" /* SUXX, ignores features.h */
28
29 #if USE_IN_GIF
30
31 #include "cgif.h"
32 #include "cgif.c" /* _POSIX_SOURCE */
33 #include "image.hpp"
34 #include "error.hpp"
35 #include "gensio.hpp"
36
37 #undef CGIFFF
38 #define CGIFFF CGIF::
39
in_gif_reader(Image::Loader::UFD * ufd,SimBuffer::Flat const &)40 static Image::Sampled *in_gif_reader(Image::Loader::UFD *ufd, SimBuffer::Flat const&) {
41 Image::Indexed *img;
42 CGIFFF GifFileType *giff;
43 CGIFFF SavedImage *sp;
44 CGIFFF ColorMapObject *cm;
45 char const *err;
46
47 /* Dat: (CGIFFF GetGifError() || "unknown error") doesn't work like in Perl or Ruby */
48 if (0==(giff=CGIFFF DGifOpenFILE(((Filter::UngetFILED*)ufd)->getFILE(/*seekable:*/false))) || GIF_ERROR==CGIFFF DGifSlurp(giff))
49 Error::sev(Error::EERROR) << "GIF: " << ((err=CGIFFF GetGifError()) ? err : "unknown error") << (Error*)0;
50 if (giff->ImageCount<1)
51 Error::sev(Error::EERROR) << "GIF: no image in file" << (Error*)0;
52
53 sp=giff->SavedImages+0;
54 cm = (sp->ImageDesc.ColorMap ? sp->ImageDesc.ColorMap : giff->SColorMap);
55 img=new Image::Indexed(sp->ImageDesc.Width, sp->ImageDesc.Height, cm->ColorCount, 8);
56 CGIFFF GifColorType *co=cm->Colors, *ce=co+cm->ColorCount;
57 char *p=img->getHeadp();
58 while (co!=ce) { *p++=(char)co->Red; *p++=(char)co->Green; *p++=(char)co->Blue; co++; }
59 // fprintf(stderr, "transp=%d\n", sp->transp);
60 if (sp->transp!=-1) img->setTransp(sp->transp);
61 /* ^^^ comment out this line to ignore transparency of the GIF file */
62
63 assert(1L*sp->ImageDesc.Width*sp->ImageDesc.Height<=img->end_()-img->getRowbeg());
64 memcpy(img->getRowbeg(), sp->RasterBits, (slen_t)sp->ImageDesc.Width*sp->ImageDesc.Height);
65
66 CGIFFF DGifCloseFile(giff); /* also frees memory structure */
67
68 return img;
69 }
70
in_gif_checker(char buf[Image::Loader::MAGIC_LEN],char[Image::Loader::MAGIC_LEN],SimBuffer::Flat const &,Image::Loader::UFD *)71 static Image::Loader::reader_t in_gif_checker(char buf[Image::Loader::MAGIC_LEN], char [Image::Loader::MAGIC_LEN], SimBuffer::Flat const&, Image::Loader::UFD*) {
72 return (0==memcmp(buf,"GIF87a",6) || 0==memcmp(buf,"GIF89a",6)) ? in_gif_reader : 0;
73 }
74
75 #define in_gif_name "GIF"
76
77 #else
78 #include <string.h>
79 #include "image.hpp"
80 #include "error.hpp"
81 #define in_gif_name (char const*)NULLP
82 /* #define in_gif_checker (Image::Loader::checker_t)NULLP */
in_gif_checker(char buf[Image::Loader::MAGIC_LEN],char[Image::Loader::MAGIC_LEN],SimBuffer::Flat const &,Image::Loader::UFD *)83 static Image::Loader::reader_t in_gif_checker(char buf[Image::Loader::MAGIC_LEN], char [Image::Loader::MAGIC_LEN], SimBuffer::Flat const&, Image::Loader::UFD*) {
84 if (0==memcmp(buf,"GIF87a",6) || 0==memcmp(buf,"GIF89a",6)) {
85 Error::sev(Error::WARNING) << "loader: please `configure --enable-gif' for loading GIF files" << (Error*)0;
86 }
87 return 0;
88 }
89 #endif /* USE_IN_GIF */
90
91 Image::Loader in_gif_loader = { in_gif_name, in_gif_checker, 0 };
92