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authorMichael Vogt <mvo@debian.org>2014-05-14 18:04:48 +0200
committerMichael Vogt <mvo@debian.org>2014-05-14 18:04:48 +0200
commite110d7bf5675f484c06b82f621ac98bedc464865 (patch)
tree70ce5da7ad75ccbaf4b30cf4809209993ba98b23 /apt-pkg/tagfile.cc
parent0b58b3f8917a49d83154fd3173bca36c1d617ef0 (diff)
parent4f6d26b4d41474aa390329b7e9cb167eb70b2821 (diff)
Merge remote-tracking branch 'donkult/debian/experimental' into debian/experimental
Conflicts: apt-pkg/acquire-item.cc apt-pkg/acquire-item.h
Diffstat (limited to 'apt-pkg/tagfile.cc')
-rw-r--r--apt-pkg/tagfile.cc209
1 files changed, 131 insertions, 78 deletions
diff --git a/apt-pkg/tagfile.cc b/apt-pkg/tagfile.cc
index 009ed7d74..52f4da2d5 100644
--- a/apt-pkg/tagfile.cc
+++ b/apt-pkg/tagfile.cc
@@ -47,6 +47,22 @@ public:
unsigned long long Size;
};
+static unsigned long AlphaHash(const char *Text, size_t Length) /*{{{*/
+{
+ /* This very simple hash function for the last 8 letters gives
+ very good performance on the debian package files */
+ if (Length > 8)
+ {
+ Text += (Length - 8);
+ Length = 8;
+ }
+ unsigned long Res = 0;
+ for (size_t i = 0; i < Length; ++i)
+ Res = ((unsigned long)(Text[i]) & 0xDF) ^ (Res << 1);
+ return Res & 0xFF;
+}
+ /*}}}*/
+
// TagFile::pkgTagFile - Constructor /*{{{*/
// ---------------------------------------------------------------------
/* */
@@ -139,18 +155,23 @@ bool pkgTagFile::Resize(unsigned long long const newSize)
*/
bool pkgTagFile::Step(pkgTagSection &Tag)
{
- while (Tag.Scan(d->Start,d->End - d->Start) == false)
+ if(Tag.Scan(d->Start,d->End - d->Start) == false)
{
- if (Fill() == false)
- return false;
-
- if(Tag.Scan(d->Start,d->End - d->Start))
- break;
+ do
+ {
+ if (Fill() == false)
+ return false;
+
+ if(Tag.Scan(d->Start,d->End - d->Start, false))
+ break;
+
+ if (Resize() == false)
+ return _error->Error(_("Unable to parse package file %s (1)"),
+ d->Fd.Name().c_str());
- if (Resize() == false)
- return _error->Error(_("Unable to parse package file %s (1)"),
- d->Fd.Name().c_str());
+ } while (Tag.Scan(d->Start,d->End - d->Start, false) == false);
}
+
d->Start += Tag.size();
d->iOffset += Tag.size();
@@ -244,7 +265,7 @@ bool pkgTagFile::Jump(pkgTagSection &Tag,unsigned long long Offset)
if (Fill() == false)
return false;
- if (Tag.Scan(d->Start, d->End - d->Start) == false)
+ if (Tag.Scan(d->Start, d->End - d->Start, false) == false)
return _error->Error(_("Unable to parse package file %s (2)"),d->Fd.Name().c_str());
return true;
@@ -254,27 +275,46 @@ bool pkgTagFile::Jump(pkgTagSection &Tag,unsigned long long Offset)
// ---------------------------------------------------------------------
/* */
pkgTagSection::pkgTagSection()
- : Section(0), TagCount(0), d(NULL), Stop(0)
+ : Section(0), d(NULL), Stop(0)
{
- memset(&Indexes, 0, sizeof(Indexes));
- memset(&AlphaIndexes, 0, sizeof(AlphaIndexes));
+ memset(&LookupTable, 0, sizeof(LookupTable));
}
/*}}}*/
// 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)
+bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength, bool const Restart)
{
+ Section = Start;
const char *End = Start + MaxLength;
- Stop = Section = Start;
- memset(AlphaIndexes,0,sizeof(AlphaIndexes));
+
+ if (Restart == false && Tags.empty() == false)
+ {
+ Stop = Section + Tags.back().StartTag;
+ if (End <= Stop)
+ return false;
+ Stop = (const char *)memchr(Stop,'\n',End - Stop);
+ if (Stop == NULL)
+ return false;
+ ++Stop;
+ }
+ else
+ {
+ Stop = Section;
+ if (Tags.empty() == false)
+ {
+ memset(&LookupTable, 0, sizeof(LookupTable));
+ Tags.clear();
+ }
+ Tags.reserve(0x100);
+ }
+ size_t TagCount = Tags.size();
if (Stop == 0)
return false;
- TagCount = 0;
- while (TagCount+1 < sizeof(Indexes)/sizeof(Indexes[0]) && Stop < End)
+ TagData lastTagData(0);
+ lastTagData.EndTag = 0;
+ unsigned long lastTagHash = 0;
+ while (Stop < End)
{
TrimRecord(true,End);
@@ -286,12 +326,39 @@ bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength)
// Start a new index and add it to the hash
if (isspace(Stop[0]) == 0)
{
- Indexes[TagCount++] = Stop - Section;
- AlphaIndexes[AlphaHash(Stop,End)] = TagCount;
+ // store the last found tag
+ if (lastTagData.EndTag != 0)
+ {
+ if (LookupTable[lastTagHash] != 0)
+ lastTagData.NextInBucket = LookupTable[lastTagHash];
+ LookupTable[lastTagHash] = TagCount;
+ Tags.push_back(lastTagData);
+ }
+
+ ++TagCount;
+ lastTagData = TagData(Stop - Section);
+ // find the colon separating tag and value
+ char const * Colon = (char const *) memchr(Stop, ':', End - Stop);
+ if (Colon == NULL)
+ return false;
+ // find the end of the tag (which might or might not be the colon)
+ char const * EndTag = Colon;
+ --EndTag;
+ for (; EndTag > Stop && isspace(*EndTag) != 0; --EndTag)
+ ;
+ ++EndTag;
+ lastTagData.EndTag = EndTag - Section;
+ lastTagHash = AlphaHash(Stop, EndTag - Stop);
+ // find the beginning of the value
+ Stop = Colon + 1;
+ for (; isspace(*Stop) != 0; ++Stop);
+ if (Stop >= End)
+ return false;
+ lastTagData.StartValue = Stop - Section;
}
Stop = (const char *)memchr(Stop,'\n',End - Stop);
-
+
if (Stop == 0)
return false;
@@ -302,7 +369,16 @@ bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength)
// Double newline marks the end of the record
if (Stop+1 < End && Stop[1] == '\n')
{
- Indexes[TagCount] = Stop - Section;
+ if (lastTagData.EndTag != 0)
+ {
+ if (LookupTable[lastTagHash] != 0)
+ lastTagData.NextInBucket = LookupTable[lastTagHash];
+ LookupTable[lastTagHash] = TagCount;
+ Tags.push_back(lastTagData);
+ }
+
+ TagData const td(Stop - Section);
+ Tags.push_back(td);
TrimRecord(false,End);
return true;
}
@@ -331,8 +407,8 @@ void pkgTagSection::Trim()
for (; Stop > Section + 2 && (Stop[-2] == '\n' || Stop[-2] == '\r'); Stop--);
}
/*}}}*/
-// TagSection::Exists - return True if a tag exists /*{{{*/
-bool pkgTagSection::Exists(const char* const Tag)
+// TagSection::Exists - return True if a tag exists /*{{{*/
+bool pkgTagSection::Exists(const char* const Tag) const
{
unsigned int tmp;
return Find(Tag, tmp);
@@ -343,73 +419,43 @@ bool pkgTagSection::Exists(const char* const Tag)
/* This searches the section for a tag that matches the given string. */
bool pkgTagSection::Find(const char *Tag,unsigned int &Pos) const
{
- unsigned int Length = strlen(Tag);
- unsigned int I = AlphaIndexes[AlphaHash(Tag)];
- if (I == 0)
+ size_t const Length = strlen(Tag);
+ unsigned int Bucket = LookupTable[AlphaHash(Tag, Length)];
+ if (Bucket == 0)
return false;
- I--;
-
- for (unsigned int Counter = 0; Counter != TagCount; Counter++,
- I = (I+1)%TagCount)
+
+ for (; Bucket != 0; Bucket = Tags[Bucket - 1].NextInBucket)
{
- const char *St;
- St = Section + Indexes[I];
- if (strncasecmp(Tag,St,Length) != 0)
+ if ((Tags[Bucket - 1].EndTag - Tags[Bucket - 1].StartTag) != Length)
continue;
- // Make sure the colon is in the right place
- const char *C = St + Length;
- for (; isspace(*C) != 0; C++);
- if (*C != ':')
+ char const * const St = Section + Tags[Bucket - 1].StartTag;
+ if (strncasecmp(Tag,St,Length) != 0)
continue;
- Pos = I;
+
+ Pos = Bucket - 1;
return true;
}
Pos = 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) const
{
- unsigned int Length = strlen(Tag);
- unsigned int I = AlphaIndexes[AlphaHash(Tag)];
- if (I == 0)
+ unsigned int Pos;
+ if (Find(Tag, Pos) == false)
return false;
- I--;
-
- for (unsigned int Counter = 0; Counter != TagCount; Counter++,
- I = (I+1)%TagCount)
- {
- const char *St;
- St = Section + Indexes[I];
- if (strncasecmp(Tag,St,Length) != 0)
- continue;
-
- // Make sure the colon is in the right place
- const char *C = St + Length;
- for (; isspace(*C) != 0; C++);
- if (*C != ':')
- continue;
- // Strip off the gunk from the start end
- Start = C;
- End = Section + Indexes[I+1];
- if (Start >= End)
- return _error->Error("Internal parsing error");
-
- for (; (isspace(*Start) != 0 || *Start == ':') && Start < End; Start++);
- for (; isspace(End[-1]) != 0 && End > Start; End--);
-
- return true;
- }
-
- Start = End = 0;
- return false;
+ Start = Section + Tags[Pos].StartValue;
+ // Strip off the gunk from the end
+ End = Section + Tags[Pos + 1].StartTag;
+ if (unlikely(Start > End))
+ return _error->Error("Internal parsing error");
+
+ for (; isspace(End[-1]) != 0 && End > Start; --End);
+
+ return true;
}
/*}}}*/
// TagSection::FindS - Find a string /*{{{*/
@@ -504,6 +550,13 @@ bool pkgTagSection::FindFlag(unsigned long &Flags, unsigned long Flag,
return true;
}
/*}}}*/
+APT_PURE unsigned int pkgTagSection::Count() const { /*{{{*/
+ if (Tags.empty() == true)
+ return 0;
+ // the last element is just marking the end and isn't a real one
+ return Tags.size() - 1;
+}
+ /*}}}*/
// TFRewrite - Rewrite a control record /*{{{*/
// ---------------------------------------------------------------------
/* This writes the control record to stdout rewriting it as necessary. The