diff options
Diffstat (limited to 'apt-pkg/tagfile.cc')
| -rw-r--r-- | apt-pkg/tagfile.cc | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/apt-pkg/tagfile.cc b/apt-pkg/tagfile.cc new file mode 100644 index 000000000..106b0febe --- /dev/null +++ b/apt-pkg/tagfile.cc @@ -0,0 +1,195 @@ +// -*- mode: cpp; mode: fold -*- +// Description /*{{{*/ +// $Id: tagfile.cc,v 1.1 1998/07/02 02:58:13 jgg Exp $ +/* ###################################################################### + + Fast scanner for RFC-822 type header information + + This uses a rotating 64K buffer to load the package information into. + The scanner runs over it and isolates and indexes a single section. + + ##################################################################### */ + /*}}}*/ +// Include Files /*{{{*/ +#include <pkglib/tagfile.h> +#include <pkglib/error.h> + +#include <string> +#include <stdio.h> + /*}}}*/ + +// TagFile::pkgTagFile - Constructor /*{{{*/ +// --------------------------------------------------------------------- +/* */ +pkgTagFile::pkgTagFile(File &Fd) : Fd(Fd) +{ + Buffer = new char[64*1024]; + Start = End = Buffer + 64*1024; + Left = Fd.Size(); + Fill(); +} + /*}}}*/ +// TagFile::Step - Advance to the next section /*{{{*/ +// --------------------------------------------------------------------- +/* If the Section Scanner fails we refill the buffer and try again. */ +bool pkgTagFile::Step(pkgTagSection &Tag) +{ + if (Tag.Scan(Start,End - Start) == false) + { + if (Fill() == false) + return false; + + if (Tag.Scan(Start,End - Start) == false) + return _error->Error("Unable to parse package file"); + } + Start += Tag.Length(); + return true; +} + /*}}}*/ +// TagFile::Fill - Top up the buffer /*{{{*/ +// --------------------------------------------------------------------- +/* This takes the bit at the end of the buffer and puts it at the start + then fills the rest from the file */ +bool pkgTagFile::Fill() +{ + unsigned long Size = End - Start; + + if (Left == 0) + { + if (Size <= 1) + return false; + return true; + } + + memmove(Buffer,Start,Size); + Start = Buffer; + + // See if only a bit of the file is left or if + if (Left < End - Buffer - Size) + { + if (Fd.Read(Buffer + Size,Left) == false) + return false; + End = Buffer + Size + Left; + Left = 0; + } + else + { + if (Fd.Read(Buffer + Size, End - Buffer - Size) == false) + return false; + Left -= End - Buffer - Size; + } + return true; +} + /*}}}*/ +// TagSection::Scan - Scan for the end of the header information /*{{{*/ +// --------------------------------------------------------------------- +/* This looks for the first double new line in the data stream. It also + indexes the tags in the section. */ +bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength) +{ + const char *End = Start + MaxLength; + Stop = Section = Start; + + TagCount = 0; + Indexes[TagCount++] = Stop - Section; + Stop++; + for (; Stop < End; Stop++) + { + if (Stop[-1] != '\n') + continue; + if (Stop[0] == '\n') + { + // Extra one at the end to simplify find + Indexes[TagCount] = Stop - Section; + for (; Stop[0] == '\n' && Stop < End; Stop++); + return true; + break; + } + + if (isspace(Stop[0]) == 0) + Indexes[TagCount++] = Stop - Section; + + // Just in case. + if (TagCount > sizeof(Indexes)/sizeof(Indexes[0])) + TagCount = sizeof(Indexes)/sizeof(Indexes[0]); + } + return false; +} + /*}}}*/ +// TagSection::Find - Locate a tag /*{{{*/ +// --------------------------------------------------------------------- +/* This searches the section for a tag that matches the given string. */ +bool pkgTagSection::Find(const char *Tag,const char *&Start, + const char *&End) +{ + unsigned int Length = strlen(Tag); + for (unsigned int I = 0; I != TagCount; I++) + { + if (strncasecmp(Tag,Section + Indexes[I],Length) != 0) + continue; + + // Make sure the colon is in the right place + const char *C = Section + Length + Indexes[I]; + for (; isspace(*C) != 0; C++); + if (*C != ':') + continue; + + // Strip off the gunk from the start end + Start = C; + End = Section + Indexes[I+1]; + for (; (isspace(*Start) != 0 || *Start == ':') && Start < End; Start++); + for (; isspace(End[-1]) != 0 && End > Start; End--); + return true; + } + Start = End = 0; + return false; +} + /*}}}*/ + +#include <pkglib/pkgcachegen.h> + +int main(int argc,char *argv[]) +{ + { + File F(argv[1],File::ReadOnly); + pkgTagFile Test(F); + File CacheF("./cache",File::WriteEmpty); + DynamicMMap Map(CacheF,MMap::Public); + pkgCacheGenerator Gen(Map); + Gen.SelectFile("tet"); + } + +#if 0 + pkgTagSection I; + while (Test.Step(I) == true) + { + const char *Start; + const char *End; + if (I.Find("Package",Start,End) == false) + { + cout << "Failed" << endl; + continue; + } + + cout << "Package: " << string(Start,End - Start) << endl; + +/* for (const char *I = Start; I < End; I++) + { + const char *Begin = I; + bool Number = true; + while (isspace(*I) == 0 && ispunct(*I) == 0 && I < End) + { + if (isalpha(*I) != 0) + Number = false; + I++; + } + if (Number == false) + cout << string(Begin,I-Begin) << endl; + while ((isspace(*I) != 0 || ispunct(*I) != 0) && I < End) + I++; + I--; + } */ + } +#endif + _error->DumpErrors(); +} |