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[Launchpad Bug Tracker <1342459@xxxxxxxxxxxxxxxxxx>]

Status changed to 'Confirmed' because the bug affects multiple users.

** Changed in: libmng (Ubuntu)
       Status: New => Confirmed

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https://bugs.launchpad.net/bugs/1342459

Title:
  doesn't include <stdio.h> before <jpeglib.h>

Status in libmng package in Ubuntu:
  Confirmed

Bug description:
  libmng 2.0.2-0ubuntu3 in Ubuntu 14.04 (trusty), gcc 4.8.

  tldr summary: libmng_types.h should #include <stdio.h> before
  <jpeglib.h>.  Could also check for HAVE_BOOLEAN being defined before
  defining it.

  details:
  http://www.freedesktop.org/wiki/Software/libjpeg/

  "Applications using the JPEG library should include the header file
  jpeglib.h to obtain declarations of data types and routines. Before
  including jpeglib.h, include system headers that define at least the
  typedefs FILE and size_t."

   So libjpeg is a special snowflake and doesn't #include the necessary
  headers to define all the types it mentions.  Presumably this is for
  small footprint things that don't need the stdio parts of libjpeg, and
  can hack something up to make it compile without pulling in <stdio.h>.

   libmng 2.0.2 doesn't do this, so this won't compile:
  #include <libmng.h>
  int main() { return 0; }

  
  In file included from /usr/include/libmng_types.h:203:0,
                   from /usr/include/libmng.h:386,
                   from mng-inc.c:1:
  /usr/include/jpeglib.h:1000:30: error: unknown type name ‘FILE’
   EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile));
                                ^
  /usr/include/jpeglib.h:1001:29: error: unknown type name ‘FILE’
   EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile));

   This breaks autoconf detection of libmng when compiling mplayer from
  source, for example.

   The obvious fix is for libmng_types.h to #include <stdio.h> right
  before jpeglib.h.

   If cleaning up the headers anyway, the typedef int boolean;
  apparently caused a problem for someone when compiling the GIMP with
  some version of jpeglib, as it includes jpeglib.h before libmng.h.
  https://sourceforge.net/p/png-mng/mailman/message/31502284/.  (which I
  noticed since it showed up on the same page as the message about
  mplayer's autoconf test for libmng.)

   I had a look: jpeglib checks for but doesn't set HAVE_BOOLEAN, and
  libmng sets HAVE_BOOLEAN without checking.

  // in jmorecfg.h
  #ifndef HAVE_BOOLEAN
  typedef int boolean;
  #endif

  // in libmng_types.h
  #ifndef _WIN32
  #define HAVE_BOOLEAN
  typedef int boolean;
  #endif

   It's not an error to have multiple identical typedefs, so presumably
  the problem happened with a different libjpeg version that defined
  boolean to something else.  I'm not sure what the point of the logic
  is, though.  Surely testing on #ifndef HAVE_BOOLEAN would be a good
  idea.  i.e.

  #if !defined(HAVE_BOOLEAN) && !defined(_WIN32)
  #define HAVE_BOOLEAN
  typedef int boolean;
  #endif

   I assume the idea is to avoid defining it at all on win32.  So I
  guess code that wants to compile on win32 depends on jpeglib.h
  (included by libmng.h) providing a typedef for boolean, or depends on
  having boolean defined by windows stuff.  It might make more sense
  just to remove defining boolean from libmng_types.h altogether, if it
  can do without it and still compile on win32.  This could break things
  if using libmng.h with a different jpeglib.h that didn't provide a
  typedef for boolean, so the safest would be the  #if
  !defined(HAVE_BOOLEAN) && !defined(_WIN32)  check.

   Anyway, both of these were reported on the mailing list right after
  2.0.2 released, without replies or updates from upstream.  And
  upstream's sourceforge ticket tracker
  (https://sourceforge.net/p/libmng/bugs/) doesn't allow ticket
  creation.  So I'm reporting it here instead of trying to chase down
  upstream maintainers myself.

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