Re: [pdf-devel] I'm Back at last

[gerel]

 > I was thinking in a scheme like the following:
 > 
 > Base Layer Modules:
 > 
 >  pdf_<module-name>[_<module-component>].[ch]
 > 
 > Object Layer Modules:
 > 
 >  pdf_o_<module-name>[_<module-component>].[ch]
 > 
 > Document Layer Modules:
 > 
 >  pdf_d_<module-name>[_<module-component>].[ch]
 > 
 > Page Layer Modules:
 > 
 >  pdf_p_<module-name>[_<module-component>].[ch]
 > 
 > What do you think?

Sure, I like it. If everyone agrees change names ASAP :-)

 > BTW, to avoid confusions with the PDF stream objects it is better to
 > consistently call the base layer streams as "stms".

Yes, I was thinking of directly changing the name of the stms module to
'buffer'/'sink' module or something. The names got me confused at first.
 
 > Note that the processing of a PDF file (maybe linearized) will involve the
 > use of several stms. For example, the presence of a object stream will
 > require to use an extra stm with a different filter chain installed to allow
 > the parser to read the objects contained into it.

Exactly.

 >    3. For pdf_error I'm considering writing wrappers for those functions
 >    available on lib/error.c and to write new ones for gnupdf as needed. OTOH,
 >    I'm pretty new on the project to know which error types should be added. I
 >    guess we should analyse each module on each layer and decide from there,
 >    don't you ?
 > 
 > Yes. Each module should be able to define several error conditions on top of
 > a generic mechanism provided by the error module (the module-specific error
 > conditions can be implemented in pdf_error.h and not in pdf_<module>).
 > 
 > I would suggest to design the generic mechanisms first. Maybe maintaining a
 > global data structure containing a stack of error events (ala errno).

This is what I have so far:

--- pdf_error.h ---

/* Time-stamp: <2007-12-13 09:28:59 gerel> */

#ifndef PDF_ERROR_H
#define PDF_ERROR_H

#define PDF_ERROR 1

enum pdf_error_t
{
     /* foo module errros */
     PDF_EINVCHAR = 0,
     PDF_EINVSYNTAX,
     PDF_EEOF,
     /* memory module errors */
     PDF_EOUTOFMEM
     /* general errors */
     PDF_EFATAL
};

extern enum pdf_error_t pdf_errno;

extern void pdf_perror (const char *str);

/* Print a message with `fprintf (stderr, FORMAT, ...)';
   if ERRNUM is nonzero, follow it with ": " and strerror (ERRNUM).
   If STATUS is nonzero, terminate the program with `exit (STATUS)'.  */
extern void pdf_error (int status, int errnum, const char *format, ...);

extern void pdf_error_at_line (int status, int errnum, const char *fname,
                               unsigned int lineno, const char *format, ...);

/* If NULL, error will flush stdout, then print on stderr the program
   name, a colon and a space.  Otherwise, error will call this
   function without parameters instead.  */
extern void (*error_print_progname) (void);

/* This variable is incremented each time `error' is called.  */
extern unsigned int pdf_error_message_count;

/* Sometimes we want to have at most one error per line.  This
   variable controls whether this mode is selected or not.  */
extern int pdf_error_one_per_line;


#endif /* PDF_ERROR_H */

--- pdf_error.h ---


 > BTW, you will need a wiki account in order to write down the
 > architecture/design of the error module. I will create one and send you the
 > login information.

Thanks, I just logged in.


-gerel