lib/base/rawfile.cpp

   1 #include <cstdio>
   2 #include <unistd.h>
   3 #include <fcntl.h>
   4 #include <lib/base/rawfile.h>
   5 #include <lib/base/eerror.h>
   6
   7 eRawFile::eRawFile()
   8 {
   9         m_fd = -1;
  10         m_file = 0;
  11         m_splitsize = 0;
  12         m_totallength = 0;
  13         m_current_offset = 0;
  14         m_base_offset = 0;
  15         m_last_offset = 0;
  16         m_nrfiles = 0;
  17         m_current_file = 0;
  18 }
  19
  20 eRawFile::~eRawFile()
  21 {
  22         close();
  23 }
  24
  25 int eRawFile::open(const char *filename, int cached)
  26 {
  27         close();
  28         m_cached = cached;
  29         m_basename = filename;
  30         scan();
  31         m_current_offset = 0;
  32         m_last_offset = 0;
  33         if (!m_cached)
  34         {
  35                 m_fd = ::open(filename, O_RDONLY | O_LARGEFILE);
  36                 return m_fd;
  37         } else
  38         {
  39                 m_file = ::fopen64(filename, "rb");
  40                 if (!m_file)
  41                         return -1;
  42                 return 0;
  43         }
  44 }
  45
  46 void eRawFile::setfd(int fd)
  47 {
  48         close();
  49         m_cached = 0;
  50         m_nrfiles = 1;
  51         m_fd = fd;
  52 }
  53
  54 off_t eRawFile::lseek(off_t offset, int whence)
  55 {
  56 //      eDebug("lseek: %lld, %d", offset, whence);
  57                 /* if there is only one file, use the native lseek - the file could be growing! */
  58         if (m_nrfiles < 2)
  59         {
  60                 if (!m_cached)
  61                         return ::lseek(m_fd, offset, whence);
  62                 else
  63                 {
  64                         ::fseeko(m_file, offset, whence);
  65                         return ::ftello(m_file);
  66                 }
  67         }
  68         switch (whence)
  69         {
  70         case SEEK_SET:
  71                 m_current_offset = offset;
  72                 break;
  73         case SEEK_CUR:
  74                 m_current_offset += offset;
  75                 break;
  76         case SEEK_END:
  77                 m_current_offset = m_totallength + offset;
  78                 break;
  79         }
  80
  81         if (m_current_offset < 0)
  82                 m_current_offset = 0;
  83         return m_current_offset;
  84 }
  85
  86 int eRawFile::close()
  87 {
  88         if (m_cached)
  89         {
  90                 if (!m_file)
  91                         return -1;
  92                 ::fclose(m_file);
  93                 m_file = 0;
  94                 return 0;
  95         } else
  96         {
  97                 int ret = ::close(m_fd);
  98                 m_fd = -1;
  99                 return ret;
 100         }
 101 }
 102
 103 ssize_t eRawFile::read(void *buf, size_t count)
 104 {
 105 //      eDebug("read: %p, %d", buf, count);
 106         switchOffset(m_current_offset);
 107
 108         if (m_nrfiles >= 2)
 109         {
 110                 if (m_current_offset + count > m_totallength)
 111                         count = m_totallength - m_current_offset;
 112                 if (count < 0)
 113                         return 0;
 114         }
 115
 116         int ret;
 117
 118         if (!m_cached)
 119                 ret = ::read(m_fd, buf, count);
 120         else
 121                 ret = ::fread(buf, 1, count, m_file);
 122
 123         if (ret > 0)
 124                 m_current_offset = m_last_offset += ret;
 125         return ret;
 126 }
 127
 128 int eRawFile::valid()
 129 {
 130         if (!m_cached)
 131                 return m_fd != -1;
 132         else
 133                 return !!m_file;
 134 }
 135
 136 void eRawFile::scan()
 137 {
 138         m_nrfiles = 0;
 139         m_totallength = 0;
 140         while (m_nrfiles < 1000) /* .999 is the last possible */
 141         {
 142                 if (!m_cached)
 143                 {
 144                         int f = openFileUncached(m_nrfiles);
 145                         if (f < 0)
 146                                 break;
 147                         if (!m_nrfiles)
 148                                 m_splitsize = ::lseek(f, 0, SEEK_END);
 149                         m_totallength += ::lseek(f, 0, SEEK_END);
 150                         ::close(f);
 151                 } else
 152                 {
 153                         FILE *f = openFileCached(m_nrfiles);
 154                         if (!f)
 155                                 break;
 156                         ::fseeko(f, 0, SEEK_END);
 157                         if (!m_nrfiles)
 158                                 m_splitsize = ::ftello(f);
 159                         m_totallength += ::ftello(f);
 160                         ::fclose(f);
 161                 }
 162
 163                 ++m_nrfiles;
 164         }
 165 //      eDebug("found %d files, splitsize: %llx, totallength: %llx", m_nrfiles, m_splitsize, m_totallength);
 166 }
 167
 168 int eRawFile::switchOffset(off_t off)
 169 {
 170         if (m_splitsize)
 171         {
 172                 int filenr = off / m_splitsize;
 173                 if (filenr >= m_nrfiles)
 174                         filenr = m_nrfiles - 1;
 175                 if (filenr != m_current_file)
 176                 {
 177 //                      eDebug("-> %d", filenr);
 178                         close();
 179                         if (!m_cached)
 180                                 m_fd = openFileUncached(filenr);
 181                         else
 182                                 m_file = openFileCached(filenr);
 183                         m_last_offset = m_base_offset = m_splitsize * filenr;
 184                         m_current_file = filenr;
 185                 }
 186         } else
 187                 m_base_offset = 0;
 188
 189         if (off != m_last_offset)
 190         {
 191                 if (!m_cached)
 192                         m_last_offset = ::lseek(m_fd, off - m_base_offset, SEEK_SET) + m_base_offset;
 193                 else
 194                 {
 195                         ::fseeko(m_file, off - m_base_offset, SEEK_SET);
 196                         m_last_offset = ::ftello(m_file) + m_base_offset;
 197                 }
 198                 return m_last_offset;
 199         } else
 200         {
 201                 return m_last_offset;
 202         }
 203 }
 204
 205 /* m_cached */
 206 FILE *eRawFile::openFileCached(int nr)
 207 {
 208         std::string filename = m_basename;
 209         if (nr)
 210         {
 211                 char suffix[5];
 212                 snprintf(suffix, 5, ".%03d", nr);
 213                 filename += suffix;
 214         }
 215         return ::fopen64(filename.c_str(), "rb");
 216 }
 217
 218 /* !m_cached */
 219 int eRawFile::openFileUncached(int nr)
 220 {
 221         std::string filename = m_basename;
 222         if (nr)
 223         {
 224                 char suffix[5];
 225                 snprintf(suffix, 5, ".%03d", nr);
 226                 filename += suffix;
 227         }
 228         return ::open(filename.c_str(), O_RDONLY | O_LARGEFILE);
 229 }