diff options
Diffstat (limited to 'erts/emulator/drivers/common/zlib_drv.c')
| -rw-r--r-- | erts/emulator/drivers/common/zlib_drv.c | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/erts/emulator/drivers/common/zlib_drv.c b/erts/emulator/drivers/common/zlib_drv.c index 3143e4511d..f7b2d91d23 100644 --- a/erts/emulator/drivers/common/zlib_drv.c +++ b/erts/emulator/drivers/common/zlib_drv.c @@ -62,8 +62,17 @@ #define CRC32_COMBINE 23 #define ADLER32_COMBINE 24 +#define INFLATE_CHUNK 25 + + #define DEFAULT_BUFSZ 4000 +/* This flag is used in the same places, where zlib return codes + * (Z_OK, Z_STREAM_END, Z_NEED_DICT) are. So, we need to set it to + * relatively large value to avoid possible value clashes in future. + * */ +#define INFLATE_HAS_MORE 100 + static int zlib_init(void); static ErlDrvData zlib_start(ErlDrvPort port, char* buf); static void zlib_stop(ErlDrvData e); @@ -295,6 +304,58 @@ static int zlib_inflate(ZLibData* d, int flush) return res; } +static int zlib_inflate_chunk(ZLibData* d) +{ + int res = Z_OK; + + if ((d->bin == NULL) && (zlib_output_init(d) < 0)) { + errno = ENOMEM; + return Z_ERRNO; + } + + while ((driver_sizeq(d->port) > 0) && (d->s.avail_out > 0) && + (res != Z_STREAM_END)) { + int vlen; + SysIOVec* iov = driver_peekq(d->port, &vlen); + int len; + + d->s.next_in = iov[0].iov_base; + d->s.avail_in = iov[0].iov_len; + while((d->s.avail_in > 0) && (d->s.avail_out > 0) && (res != Z_STREAM_END)) { + res = inflate(&d->s, Z_NO_FLUSH); + if (res == Z_NEED_DICT) { + /* Essential to eat the header bytes that zlib has looked at */ + len = iov[0].iov_len - d->s.avail_in; + driver_deq(d->port, len); + return res; + } + if (res == Z_BUF_ERROR) { + /* Was possible more output, but actually not */ + res = Z_OK; + } + else if (res < 0) { + return res; + } + } + len = iov[0].iov_len - d->s.avail_in; + driver_deq(d->port, len); + } + + /* We are here because all input was consumed or EOS reached or output + * buffer is full */ + if (d->want_crc) { + d->crc = crc32(d->crc, (unsigned char*) d->bin->orig_bytes, + d->binsz - d->s.avail_out); + } + zlib_output(d); + if ((res == Z_OK) && (d->s.avail_in > 0)) + res = INFLATE_HAS_MORE; + else if (res == Z_STREAM_END) { + d->inflate_eos_seen = 1; + } + return res; +} + static int zlib_deflate(ZLibData* d, int flush) { int res = Z_OK; @@ -568,6 +629,18 @@ static ErlDrvSSizeT zlib_ctl(ErlDrvData drv_data, unsigned int command, char *bu return zlib_return(res, rbuf, rlen); } + case INFLATE_CHUNK: + if (d->state != ST_INFLATE) goto badarg; + if (len != 0) goto badarg; + res = zlib_inflate_chunk(d); + if (res == INFLATE_HAS_MORE) { + return zlib_value2(4, 0, rbuf, rlen); + } else if (res == Z_NEED_DICT) { + return zlib_value2(3, d->s.adler, rbuf, rlen); + } else { + return zlib_return(res, rbuf, rlen); + } + case GET_QSIZE: return zlib_value(driver_sizeq(d->port), rbuf, rlen); |