eBookReaderSwitch/source/fitz/filter-leech.c

69 lines
1.5 KiB
C

#include "fitz-imp.h"
#include <zlib.h>
#include <string.h>
typedef struct fz_leech_s fz_leech;
struct fz_leech_s
{
fz_stream *chain;
fz_buffer *buffer;
};
static int
next_leech(fz_context *ctx, fz_stream *stm, size_t max)
{
fz_leech *state = stm->state;
fz_buffer *buffer = state->buffer;
size_t n = fz_available(ctx, state->chain, max);
if (n > max)
n = max;
while (buffer->cap < buffer->len + n)
{
fz_grow_buffer(ctx, state->buffer);
}
memcpy(buffer->data + buffer->len, state->chain->rp, n);
stm->rp = buffer->data + buffer->len;
stm->wp = buffer->data + buffer->len + n;
state->chain->rp += n;
buffer->len += n;
if (n == 0)
return EOF;
return *stm->rp++;
}
static void
close_leech(fz_context *ctx, void *state_)
{
fz_leech *state = (fz_leech *)state_;
fz_drop_stream(ctx, state->chain);
fz_drop_buffer(ctx, state->buffer);
fz_free(ctx, state);
}
/*
Attach a filter to a stream that will store any
characters read from the stream into the supplied buffer.
chain: The underlying stream to leech from.
buf: The buffer into which the read data should be appended.
The buffer will be resized as required.
Returns pointer to newly created stream. May throw exceptions on
failure to allocate.
*/
fz_stream *
fz_open_leecher(fz_context *ctx, fz_stream *chain, fz_buffer *buffer)
{
fz_leech *state = fz_malloc_struct(ctx, fz_leech);
state->chain = fz_keep_stream(ctx, chain);
state->buffer = fz_keep_buffer(ctx, buffer);
return fz_new_stream(ctx, state, next_leech, close_leech);
}