diff options
Diffstat (limited to 'server/zlib_encoder.c')
-rw-r--r-- | server/zlib_encoder.c | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/server/zlib_encoder.c b/server/zlib_encoder.c new file mode 100644 index 00000000..e0d8d830 --- /dev/null +++ b/server/zlib_encoder.c @@ -0,0 +1,104 @@ +#include "red_common.h" +#include "zlib_encoder.h" +#include <zlib.h> + +struct ZlibEncoder { + ZlibEncoderUsrContext *usr; + + z_stream strm; + int last_level; +}; + +ZlibEncoder* zlib_encoder_create(ZlibEncoderUsrContext *usr, int level) +{ + ZlibEncoder *enc; + int z_ret; + + if (!usr->more_space || !usr->more_input) { + return NULL; + } + + enc = spice_new0(ZlibEncoder, 1); + + enc->usr = usr; + + enc->strm.zalloc = Z_NULL; + enc->strm.zfree = Z_NULL; + enc->strm.opaque = Z_NULL; + + z_ret = deflateInit(&enc->strm, level); + enc->last_level = level; + if (z_ret != Z_OK) { + red_printf("zlib error"); + free(enc); + return NULL; + } + + return enc; +} + +void zlib_encoder_destroy(ZlibEncoder *encoder) +{ + deflateEnd(&encoder->strm); + free(encoder); +} + +/* returns the total size of the encoded data */ +int zlib_encode(ZlibEncoder *zlib, int level, int input_size, + uint8_t *io_ptr, unsigned int num_io_bytes) +{ + int flush; + int enc_size = 0; + int out_size = 0; + int z_ret; + + z_ret = deflateReset(&zlib->strm); + + if (z_ret != Z_OK) { + red_error("deflateReset failed"); + } + + zlib->strm.next_out = io_ptr; + zlib->strm.avail_out = num_io_bytes; + + if (level != zlib->last_level) { + if (zlib->strm.avail_out == 0) { + zlib->strm.avail_out = zlib->usr->more_space(zlib->usr, &zlib->strm.next_out); + if (zlib->strm.avail_out == 0) { + red_error("not enough space"); + } + } + z_ret = deflateParams(&zlib->strm, level, Z_DEFAULT_STRATEGY); + if (z_ret != Z_OK) { + red_error("deflateParams failed"); + } + zlib->last_level = level; + } + + + do { + zlib->strm.avail_in = zlib->usr->more_input(zlib->usr, &zlib->strm.next_in); + if (zlib->strm.avail_in <= 0) { + red_error("more input failed\n"); + } + enc_size += zlib->strm.avail_in; + flush = (enc_size == input_size) ? Z_FINISH : Z_NO_FLUSH; + while (1) { + int deflate_size = zlib->strm.avail_out; + z_ret = deflate(&zlib->strm, flush); + ASSERT(z_ret != Z_STREAM_ERROR); + out_size += deflate_size - zlib->strm.avail_out; + if (zlib->strm.avail_out) { + break; + } + + zlib->strm.avail_out = zlib->usr->more_space(zlib->usr, &zlib->strm.next_out); + if (zlib->strm.avail_out == 0) { + red_error("not enough space"); + } + } + } while (flush != Z_FINISH); + + ASSERT(z_ret == Z_STREAM_END); + return out_size; +} |