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| 1 | + |
| 2 | +#include <cstdio> |
| 3 | +#include <cstdlib> |
| 4 | +#include <streambuf> |
| 5 | + |
| 6 | +#include <sys/mman.h> |
| 7 | +#include <sys/stat.h> |
| 8 | +#include <fcntl.h> |
| 9 | +#include <unistd.h> |
| 10 | +#include <nttec/nttec.h> |
| 11 | + |
| 12 | +#include "io_client.h" |
| 13 | + |
| 14 | +template class nttec::fec::RsFnt<uint32_t>; |
| 15 | + |
| 16 | +int vflag = 1; |
| 17 | + |
| 18 | +struct membuf : std::streambuf { |
| 19 | + membuf(char const *base, size_t size) { |
| 20 | + char *p(const_cast<char *>(base)); |
| 21 | + this->setg(p, p, p + size); |
| 22 | + } |
| 23 | +}; |
| 24 | + |
| 25 | +struct imemstream : virtual membuf, std::istream { |
| 26 | + imemstream(char const *base, size_t size) |
| 27 | + : membuf(base, size), std::istream(static_cast<std::streambuf *>(this)) {} |
| 28 | +}; |
| 29 | + |
| 30 | +/** |
| 31 | + * Create coding files for the specified file |
| 32 | + * |
| 33 | + * This function: |
| 34 | + * 1) compute the ideal mmap size |
| 35 | + * 2) mmaps the file |
| 36 | + * 3) create proper input and output streams |
| 37 | + * |
| 38 | + * @param filename source filename |
| 39 | + * @param fec encoder to use |
| 40 | + */ |
| 41 | +int create_coding_files(const char *filename, |
| 42 | + nttec::fec::FecCode<uint32_t> *fec) { |
| 43 | + void *addr; |
| 44 | + char *tmp_addr; |
| 45 | + int fd; |
| 46 | + struct stat sb; |
| 47 | + size_t length, data_size; |
| 48 | + off_t offset; |
| 49 | + char cfilename[1024]; |
| 50 | + std::vector<std::istream *> d_files(fec->n_data, nullptr); |
| 51 | + std::vector<std::ostream *> c_files(fec->n_outputs, nullptr); |
| 52 | + std::vector<std::ostream *> c_props_files(fec->n_outputs, nullptr); |
| 53 | + std::vector<nttec::Properties> c_props(fec->n_outputs); |
| 54 | + |
| 55 | + fd = open(filename, O_RDONLY); |
| 56 | + if (fd == -1) { |
| 57 | + std::cerr << "opening " << filename << " failed\n"; |
| 58 | + return -1; |
| 59 | + } |
| 60 | + |
| 61 | + if (fstat(fd, &sb) == -1) { |
| 62 | + std::cerr << "fstat " << filename << " failed\n"; |
| 63 | + return -1; |
| 64 | + } |
| 65 | + |
| 66 | + length = sb.st_size; |
| 67 | + |
| 68 | + data_size = length / fec->n_data; |
| 69 | + if (length % fec->n_data != 0) { |
| 70 | + // FIXME |
| 71 | + std::cerr << "file size is not multiple of n_data\n"; |
| 72 | + return -1; |
| 73 | + } |
| 74 | + std::cerr << "data_size " << data_size << "\n"; |
| 75 | + |
| 76 | + addr = mmap(NULL, length, PROT_READ, MAP_PRIVATE, fd, 0); |
| 77 | + if (addr == MAP_FAILED) { |
| 78 | + std::cerr << "mmap failed\n"; |
| 79 | + exit(1); |
| 80 | + } |
| 81 | + std::cerr << "length " << length << " addr " << addr << "\n"; |
| 82 | + |
| 83 | + // do it |
| 84 | + offset = 0; |
| 85 | + for (u_int32_t i = 0; i < fec->n_data; i++) { |
| 86 | + if (vflag) |
| 87 | + std::cerr << "create: opening data " << i << " offset " << offset << "\n"; |
| 88 | + tmp_addr = static_cast<char *>(addr) + offset; |
| 89 | + d_files[i] = new imemstream(tmp_addr, data_size); |
| 90 | + offset += data_size; |
| 91 | + } |
| 92 | + |
| 93 | + for (u_int32_t i = 0; i < fec->n_outputs; i++) { |
| 94 | + snprintf(cfilename, sizeof(cfilename), "%s.c%d", filename, i); |
| 95 | + if (vflag) |
| 96 | + std::cerr << "create: opening coding for writing " << filename << "\n"; |
| 97 | + c_files[i] = new std::ofstream(cfilename); |
| 98 | + snprintf(cfilename, sizeof(cfilename), "%s.c%d.props", filename, i); |
| 99 | + if (vflag) |
| 100 | + std::cerr << "create: opening coding props for writing " << filename |
| 101 | + << "\n"; |
| 102 | + c_props_files[i] = new std::ofstream(cfilename); |
| 103 | + } |
| 104 | + |
| 105 | + fec->encode_bufs(d_files, c_files, c_props); |
| 106 | + |
| 107 | + if (munmap(addr, length) != 0) { |
| 108 | + std::cerr << "munmap " << filename << " failed\n"; |
| 109 | + exit(1); |
| 110 | + } |
| 111 | + |
| 112 | + close(fd); |
| 113 | + |
| 114 | + return 0; |
| 115 | +} |
| 116 | + |
| 117 | +void do_put(const char *filename, int n_data, int n_parities) { |
| 118 | + nttec::fec::RsFnt<uint32_t> *fec; |
| 119 | + |
| 120 | + fec = new nttec::fec::RsFnt<uint32_t>(2, n_data, n_parities); |
| 121 | + if (create_coding_files(filename, fec) != 0) { |
| 122 | + return; |
| 123 | + } |
| 124 | +} |
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