diff options
| -rw-r--r-- | build2/depdb.cxx | 150 |
1 files changed, 102 insertions, 48 deletions
diff --git a/build2/depdb.cxx b/build2/depdb.cxx index 1d71a1d..da56c8b 100644 --- a/build2/depdb.cxx +++ b/build2/depdb.cxx @@ -115,13 +115,27 @@ namespace build2 // truncate the file. // if (trunc) + try + { fdtruncate (fd.get (), pos_); + } + catch (const io_error& e) + { + fail << "unable to truncate " << path << ": " << e; + } // Note: the file descriptor position can be beyond the pos_ value due to // the ifdstream buffering. That's why we need to seek to switch from // reading to writing. // - fdseek (fd.get (), pos_, fdseek_mode::set); + try + { + fdseek (fd.get (), pos_, fdseek_mode::set); + } + catch (const io_error& e) + { + fail << "unable to rewind " << path << ": " << e; + } // @@ Strictly speaking, ofdstream can throw which will leave us in a // non-destructible state. Unlikely but possible. @@ -143,39 +157,46 @@ namespace build2 // pos_ = buf_->tellg (); - // Note that we intentionally check for eof after updating the write - // position. - // - if (state_ == state::read_eof) - return nullptr; + try + { + // Note that we intentionally check for eof after updating the write + // position. + // + if (state_ == state::read_eof) + return nullptr; - getline (is_, line_); // Calls line_.erase(). + getline (is_, line_); // Calls line_.erase(). - // The line should always end with a newline. If it doesn't, then this - // line (and the rest of the database) is assumed corrupted. Also peek at - // the character after the newline. We should either have the next line or - // '\0', which is our "end marker", that is, it indicates the database - // was properly closed. - // - ifdstream::int_type c; - if (is_.fail () || // Nothing got extracted. - is_.eof () || // Eof reached before delimiter. - (c = is_.peek ()) == ifdstream::traits_type::eof ()) - { - // Preemptively switch to writing. While we could have delayed this - // until the user called write(), if the user calls read() again (for - // whatever misguided reason) we will mess up the overwrite position. + // The line should always end with a newline. If it doesn't, then this + // line (and the rest of the database) is assumed corrupted. Also peek + // at the character after the newline. We should either have the next + // line or '\0', which is our "end marker", that is, it indicates the + // database was properly closed. // - change (); - return nullptr; - } + ifdstream::int_type c; + if (is_.fail () || // Nothing got extracted. + is_.eof () || // Eof reached before delimiter. + (c = is_.peek ()) == ifdstream::traits_type::eof ()) + { + // Preemptively switch to writing. While we could have delayed this + // until the user called write(), if the user calls read() again (for + // whatever misguided reason) we will mess up the overwrite position. + // + change (); + return nullptr; + } - // Handle the "end marker". Note that the caller can still switch to the - // write mode on this line. And, after calling read() again, write to the - // next line (i.e., start from the "end marker"). - // - if (c == '\0') - state_ = state::read_eof; + // Handle the "end marker". Note that the caller can still switch to the + // write mode on this line. And, after calling read() again, write to + // the next line (i.e., start from the "end marker"). + // + if (c == '\0') + state_ = state::read_eof; + } + catch (const io_error& e) + { + fail << "unable to read from " << path << ": " << e; + } return &line_; } @@ -192,20 +213,27 @@ namespace build2 // pos_ = buf_->tellg (); - // Keep reading lines checking for the end marker after each newline. - // - ifdstream::int_type c; - do + try { - if ((c = is_.get ()) == '\n') + // Keep reading lines checking for the end marker after each newline. + // + ifdstream::int_type c; + do { - if ((c = is_.get ()) == '\0') + if ((c = is_.get ()) == '\n') { - state_ = state::read_eof; - return true; + if ((c = is_.get ()) == '\0') + { + state_ = state::read_eof; + return true; + } } - } - } while (c != ifdstream::traits_type::eof ()); + } while (c != ifdstream::traits_type::eof ()); + } + catch (const io_error& e) + { + fail << "unable to read from " << path << ": " << e; + } // Invalid database so change over to writing. // @@ -221,10 +249,17 @@ namespace build2 if (state_ != state::write) change (); - os_.write (s, static_cast<streamsize> (n)); + try + { + os_.write (s, static_cast<streamsize> (n)); - if (nl) - os_.put ('\n'); + if (nl) + os_.put ('\n'); + } + catch (const io_error& e) + { + fail << "unable to write to " << path << ": " << e; + } } void depdb:: @@ -235,10 +270,17 @@ namespace build2 if (state_ != state::write) change (); - os_.put (c); + try + { + os_.put (c); - if (nl) - os_.put ('\n'); + if (nl) + os_.put ('\n'); + } + catch (const io_error& e) + { + fail << "unable to write to " << path << ": " << e; + } } void depdb:: @@ -253,10 +295,15 @@ namespace build2 if (state_ == state::read_eof) { if (!touch) + try { is_.close (); return; } + catch (const io_error& e) + { + fail << "unable to close " << path << ": " << e; + } // While there are utime(2)/utimensat(2) (and probably something similar // for Windows), for now we just overwrite the "end marker". Hopefully @@ -277,8 +324,15 @@ namespace build2 if (mtime_check ()) start_ = system_clock::now (); - os_.put ('\0'); // The "end marker". - os_.close (); + try + { + os_.put ('\0'); // The "end marker". + os_.close (); + } + catch (const io_error& e) + { + fail << "unable to flush " << path << ": " << e; + } // On some platforms (currently confirmed on FreeBSD running as VMs) one // can sometimes end up with a modification time that is a bit after the |