104 lines
1.9 KiB
C
104 lines
1.9 KiB
C
#include "fitz.h"
|
|
|
|
#include <zlib.h>
|
|
|
|
typedef struct fz_flate_s fz_flate;
|
|
|
|
struct fz_flate_s
|
|
{
|
|
fz_stream *chain;
|
|
z_stream z;
|
|
};
|
|
|
|
static void *zalloc(void *opaque, unsigned int items, unsigned int size)
|
|
{
|
|
return fz_calloc(items, size);
|
|
}
|
|
|
|
static void zfree(void *opaque, void *ptr)
|
|
{
|
|
fz_free(ptr);
|
|
}
|
|
|
|
static int
|
|
read_flated(fz_stream *stm, unsigned char *outbuf, int outlen)
|
|
{
|
|
fz_flate *state = stm->state;
|
|
fz_stream *chain = state->chain;
|
|
z_streamp zp = &state->z;
|
|
int code;
|
|
|
|
zp->next_out = outbuf;
|
|
zp->avail_out = outlen;
|
|
|
|
while (zp->avail_out > 0)
|
|
{
|
|
if (chain->rp == chain->wp)
|
|
fz_fill_buffer(chain);
|
|
|
|
zp->next_in = chain->rp;
|
|
zp->avail_in = chain->wp - chain->rp;
|
|
|
|
code = inflate(zp, Z_SYNC_FLUSH);
|
|
|
|
chain->rp = chain->wp - zp->avail_in;
|
|
|
|
if (code == Z_STREAM_END)
|
|
{
|
|
return outlen - zp->avail_out;
|
|
}
|
|
else if (code == Z_BUF_ERROR)
|
|
{
|
|
fz_warn("premature end of data in flate filter");
|
|
return outlen - zp->avail_out;
|
|
}
|
|
else if (code == Z_DATA_ERROR && zp->avail_in == 0)
|
|
{
|
|
fz_warn("ignoring zlib error: %s", zp->msg);
|
|
return outlen - zp->avail_out;
|
|
}
|
|
else if (code != Z_OK)
|
|
{
|
|
return fz_throw("zlib error: %s", zp->msg);
|
|
}
|
|
}
|
|
|
|
return outlen - zp->avail_out;
|
|
}
|
|
|
|
static void
|
|
close_flated(fz_stream *stm)
|
|
{
|
|
fz_flate *state = stm->state;
|
|
int code;
|
|
|
|
code = inflateEnd(&state->z);
|
|
if (code != Z_OK)
|
|
fz_warn("zlib error: inflateEnd: %s", state->z.msg);
|
|
|
|
fz_close(state->chain);
|
|
fz_free(state);
|
|
}
|
|
|
|
fz_stream *
|
|
fz_open_flated(fz_stream *chain)
|
|
{
|
|
fz_flate *state;
|
|
int code;
|
|
|
|
state = fz_malloc(sizeof(fz_flate));
|
|
state->chain = chain;
|
|
|
|
state->z.zalloc = zalloc;
|
|
state->z.zfree = zfree;
|
|
state->z.opaque = NULL;
|
|
state->z.next_in = NULL;
|
|
state->z.avail_in = 0;
|
|
|
|
code = inflateInit(&state->z);
|
|
if (code != Z_OK)
|
|
fz_warn("zlib error: inflateInit: %s", state->z.msg);
|
|
|
|
return fz_new_stream(state, read_flated, close_flated);
|
|
}
|