diff options
Diffstat (limited to 'include/fitz/stm_filter.h')
| -rw-r--r-- | include/fitz/stm_filter.h | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/include/fitz/stm_filter.h b/include/fitz/stm_filter.h new file mode 100644 index 00000000..f8902f98 --- /dev/null +++ b/include/fitz/stm_filter.h @@ -0,0 +1,95 @@ +/* + * Data filters for encryption, compression and decompression. + * + * A filter has one method, process, that takes an input and an output buffer. + * + * It returns one of three statuses: + * ioneedin -- input buffer exhausted, please give me more data (wp-rp) + * ioneedout -- output buffer exhausted, please provide more space (ep-wp) + * iodone -- finished, please never call me again. ever! + * or... + * any other error object -- oops, something blew up. + * + * To make using the filter easier, three variables are updated: + * produced -- if we actually produced any new data + * consumed -- like above + * count -- number of bytes produced in total since the beginning + * + * Most filters take fz_obj as a way to specify parameters. + * In most cases, this is a dictionary that contains the same keys + * that the corresponding PDF filter would expect. + * + * The pipeline filter is special, and needs some care when chaining + * and unchaining new filters. + */ + +typedef struct fz_filter_s fz_filter; + +#define fz_ioneedin (&fz_kioneedin) +#define fz_ioneedout (&fz_kioneedout) +#define fz_iodone (&fz_kiodone) + +extern fz_error fz_kioneedin; +extern fz_error fz_kioneedout; +extern fz_error fz_kiodone; + +/* + * Evil looking macro to create an initialize a filter struct. + */ + +#define FZ_NEWFILTER(TYPE,VAR,NAME) \ + fz_error * fz_process ## NAME (fz_filter*,fz_buffer*,fz_buffer*); \ + void fz_drop ## NAME (fz_filter*); \ + TYPE *VAR; \ + *fp = fz_malloc(sizeof(TYPE)); \ + if (!*fp) return fz_outofmem; \ + (*fp)->refs = 1; \ + (*fp)->process = fz_process ## NAME ; \ + (*fp)->drop = fz_drop ## NAME ; \ + (*fp)->consumed = 0; \ + (*fp)->produced = 0; \ + (*fp)->count = 0; \ + VAR = (TYPE*) *fp + +struct fz_filter_s +{ + int refs; + fz_error* (*process)(fz_filter *filter, fz_buffer *in, fz_buffer *out); + void (*drop)(fz_filter *filter); + int consumed; + int produced; + int count; +}; + +fz_error *fz_process(fz_filter *f, fz_buffer *in, fz_buffer *out); +fz_filter *fz_keepfilter(fz_filter *f); +void fz_dropfilter(fz_filter *f); + +fz_error *fz_newpipeline(fz_filter **fp, fz_filter *head, fz_filter *tail); +fz_error *fz_chainpipeline(fz_filter **fp, fz_filter *head, fz_filter *tail, fz_buffer *buf); +void fz_unchainpipeline(fz_filter *pipe, fz_filter **oldfp, fz_buffer **oldbp); + +/* stop and reverse! special case needed for postscript only */ +void fz_pushbackahxd(fz_filter *filter, fz_buffer *in, fz_buffer *out, int n); + +fz_error *fz_newnullfilter(fz_filter **fp, int len); +fz_error *fz_newarc4filter(fz_filter **fp, unsigned char *key, unsigned keylen); +fz_error *fz_newa85d(fz_filter **filterp, fz_obj *param); +fz_error *fz_newa85e(fz_filter **filterp, fz_obj *param); +fz_error *fz_newahxd(fz_filter **filterp, fz_obj *param); +fz_error *fz_newahxe(fz_filter **filterp, fz_obj *param); +fz_error *fz_newrld(fz_filter **filterp, fz_obj *param); +fz_error *fz_newrle(fz_filter **filterp, fz_obj *param); +fz_error *fz_newdctd(fz_filter **filterp, fz_obj *param); +fz_error *fz_newdcte(fz_filter **filterp, fz_obj *param); +fz_error *fz_newfaxd(fz_filter **filterp, fz_obj *param); +fz_error *fz_newfaxe(fz_filter **filterp, fz_obj *param); +fz_error *fz_newflated(fz_filter **filterp, fz_obj *param); +fz_error *fz_newflatee(fz_filter **filterp, fz_obj *param); +fz_error *fz_newlzwd(fz_filter **filterp, fz_obj *param); +fz_error *fz_newlzwe(fz_filter **filterp, fz_obj *param); +fz_error *fz_newpredictd(fz_filter **filterp, fz_obj *param); +fz_error *fz_newpredicte(fz_filter **filterp, fz_obj *param); +fz_error *fz_newjbig2d(fz_filter **filterp, fz_obj *param); +fz_error *fz_newjpxd(fz_filter **filterp, fz_obj *param); + |