zlib/examples/gzappend.c

120 /* rotate list[0..len-1] left by rot positions, in place */
121 local void rotate(unsigned char *list, unsigned len, unsigned rot)
128     if (len < 2) return;
129     if (rot >= len) rot %= len;
133     last = list + (len - 1);
138         memcpy(list, list + 1, len - 1);
144     if (rot == len - 1) {
146         memmove(list + 1, list, len - 1);
152     cycles = gcd(len, rot);             /* number of cycles */
159             if (from > last) from -= len;   /* (pointer better not wrap) */
180     int len;
182     len = read(in->fd, in->buf, 1 << in->size);
183     if (len == -1) bye("error reading ", in->name);
184     in->left = (unsigned)len;
186     return len;
261     unsigned long crc, tot;
343     tot = strm->total_out;
344     if ((tot & 0xffffffffUL) != read4(&gz))
370     strm->total_in = tot;
388     int fd, len, ret;
409         len = fd == -1 ? 0 : read(fd, in, CHUNK);
410         if (len == -1) {
414             len = 0;
416         strm->avail_in = (unsigned)len;
418         if (len) strm->adler = crc32(strm->adler, in, (unsigned)len);
424             ret = deflate(strm, last && len == 0 ? Z_FINISH : Z_NO_FLUSH);
427                 len = write(gd, out + CHUNK - strm->avail_out - left, left);
428                 if (len == -1) bye("writing gzip file", "");
429                 left -= (unsigned)len;
432     } while (len != 0);
445         len = 8;
447             ret = write(gd, out + 8 - len, len);
449             len -= ret;
450         } while (len);