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authorJay Freeman (saurik) <saurik@saurik.com>2016-12-25 22:03:03 -0800
committerJay Freeman (saurik) <saurik@saurik.com>2016-12-25 22:03:03 -0800
commit3650e87b0cee98547024c2cb613c95f5e736971d (patch)
tree6efb2166a36724434b6a1673d4fc4bbeba286f20 /apt-pkg/tagfile.cc
parent1e33fb4ac68db5c2630de72d222d9dc10eb93272 (diff)
This is 2016 and APT already requires use of mmap.
Diffstat (limited to 'apt-pkg/tagfile.cc')
-rw-r--r--apt-pkg/tagfile.cc429
1 files changed, 68 insertions, 361 deletions
diff --git a/apt-pkg/tagfile.cc b/apt-pkg/tagfile.cc
index 72dd475b3..76e18bf4c 100644
--- a/apt-pkg/tagfile.cc
+++ b/apt-pkg/tagfile.cc
@@ -13,6 +13,7 @@
// Include Files /*{{{*/
#include<config.h>
+#include <apt-pkg/mmap.h>
#include <apt-pkg/tagfile.h>
#include <apt-pkg/tagfile-keys.h>
#include <apt-pkg/error.h>
@@ -37,10 +38,11 @@ using APT::StringView;
class APT_HIDDEN pkgTagFilePrivate /*{{{*/
{
public:
- void Reset(FileFd * const pFd, unsigned long long const pSize, pkgTagFile::Flags const pFlags)
+ void Reset(FileFd * const pFd, pkgTagFile::Flags const pFlags)
{
- if (Buffer != NULL)
- free(Buffer);
+ if (Map != NULL)
+ delete Map;
+ Map = NULL;
Buffer = NULL;
Fd = pFd;
Flags = pFlags;
@@ -48,14 +50,11 @@ public:
End = NULL;
Done = false;
iOffset = 0;
- Size = pSize;
- isCommentedLine = false;
- chunks.clear();
}
- pkgTagFilePrivate(FileFd * const pFd, unsigned long long const Size, pkgTagFile::Flags const pFlags) : Buffer(NULL)
+ pkgTagFilePrivate(FileFd * const pFd, pkgTagFile::Flags const pFlags) : Map(NULL)
{
- Reset(pFd, Size, pFlags);
+ Reset(pFd, pFlags);
}
FileFd * Fd;
pkgTagFile::Flags Flags;
@@ -64,20 +63,12 @@ public:
char *End;
bool Done;
unsigned long long iOffset;
- unsigned long long Size;
- bool isCommentedLine;
- struct FileChunk
- {
- bool const good;
- size_t length;
- FileChunk(bool const pgood, size_t const plength) : good(pgood), length(plength) {}
- };
- std::list<FileChunk> chunks;
+ MMap *Map;
~pkgTagFilePrivate()
{
- if (Buffer != NULL)
- free(Buffer);
+ if (Map != NULL)
+ delete Map;
}
};
/*}}}*/
@@ -116,42 +107,38 @@ static unsigned long BetaHash(const char *Text, size_t Length) /*{{{*/
/*}}}*/
// TagFile::pkgTagFile - Constructor /*{{{*/
-pkgTagFile::pkgTagFile(FileFd * const pFd,pkgTagFile::Flags const pFlags, unsigned long long const Size)
- : d(new pkgTagFilePrivate(pFd, Size + 4, pFlags))
+pkgTagFile::pkgTagFile(FileFd * const pFd,pkgTagFile::Flags const pFlags)
+ : d(new pkgTagFilePrivate(pFd, pFlags))
{
- Init(pFd, pFlags, Size);
+ Init(pFd, pFlags);
}
-pkgTagFile::pkgTagFile(FileFd * const pFd,unsigned long long const Size)
- : pkgTagFile(pFd, pkgTagFile::STRICT, Size)
+pkgTagFile::pkgTagFile(FileFd * const pFd)
+ : pkgTagFile(pFd, pkgTagFile::STRICT)
{
}
-void pkgTagFile::Init(FileFd * const pFd, pkgTagFile::Flags const pFlags, unsigned long long Size)
+void pkgTagFile::Init(FileFd * const pFd, pkgTagFile::Flags const pFlags)
{
- /* The size is increased by 4 because if we start with the Size of the
- filename we need to try to read 1 char more to see an EOF faster, 1
- char the end-pointer can be on and maybe 2 newlines need to be added
- to the end of the file -> 4 extra chars */
- Size += 4;
- d->Reset(pFd, Size, pFlags);
-
- if (d->Fd->IsOpen() == false)
- d->Start = d->End = d->Buffer = 0;
- else
- d->Buffer = (char*)malloc(sizeof(char) * Size);
+ d->Reset(pFd, pFlags);
+
+ if (d->Fd->IsOpen() == false || d->Fd->Size() == 0)
+ _error->Discard();
+ else {
+ d->Map = new MMap(*d->Fd, MMap::ReadOnly);
+ d->Buffer = static_cast<char *>(d->Map->Data());
+ }
if (d->Buffer == NULL)
d->Done = true;
- else
+ else {
d->Done = false;
+ d->End = d->Buffer + d->Map->Size();
+ }
- d->Start = d->End = d->Buffer;
- d->iOffset = 0;
- if (d->Done == false)
- Fill();
+ d->Start = d->Buffer;
}
-void pkgTagFile::Init(FileFd * const pFd,unsigned long long Size)
+void pkgTagFile::Init(FileFd * const pFd)
{
- Init(pFd, pkgTagFile::STRICT, Size);
+ Init(pFd, pkgTagFile::STRICT);
}
/*}}}*/
// TagFile::~pkgTagFile - Destructor /*{{{*/
@@ -166,36 +153,6 @@ APT_PURE unsigned long pkgTagFile::Offset()
return d->iOffset;
}
/*}}}*/
-// TagFile::Resize - Resize the internal buffer /*{{{*/
-// ---------------------------------------------------------------------
-/* Resize the internal buffer (double it in size). Fail if a maximum size
- * size is reached.
- */
-bool pkgTagFile::Resize()
-{
- // fail is the buffer grows too big
- if(d->Size > 1024*1024+1)
- return false;
-
- return Resize(d->Size * 2);
-}
-bool pkgTagFile::Resize(unsigned long long const newSize)
-{
- unsigned long long const EndSize = d->End - d->Start;
-
- // get new buffer and use it
- char* const newBuffer = static_cast<char*>(realloc(d->Buffer, sizeof(char) * newSize));
- if (newBuffer == NULL)
- return false;
- d->Buffer = newBuffer;
- d->Size = newSize;
-
- // update the start/end pointers to the new buffer
- d->Start = d->Buffer;
- d->End = d->Start + EndSize;
- return true;
-}
- /*}}}*/
// TagFile::Step - Advance to the next section /*{{{*/
// ---------------------------------------------------------------------
/* If the Section Scanner fails we refill the buffer and try again.
@@ -204,221 +161,18 @@ bool pkgTagFile::Resize(unsigned long long const newSize)
*/
bool pkgTagFile::Step(pkgTagSection &Tag)
{
- if(Tag.Scan(d->Start,d->End - d->Start) == false)
+ if(Tag.Scan(d->Start,d->End - d->Start,(d->Flags & SUPPORT_COMMENTS) != 0) == false)
{
- do
- {
- if (Fill() == false)
- return false;
-
- if(Tag.Scan(d->Start,d->End - d->Start, false))
- break;
-
- if (Resize() == false)
+ if (d->Start == d->End)
+ return false;
+ else
return _error->Warning(_("Unable to parse package file %s (%d)"),
d->Fd->Name().c_str(), 1);
-
- } while (Tag.Scan(d->Start,d->End - d->Start, false) == false);
}
size_t tagSize = Tag.size();
d->Start += tagSize;
-
- if ((d->Flags & pkgTagFile::SUPPORT_COMMENTS) == 0)
- d->iOffset += tagSize;
- else
- {
- auto first = d->chunks.begin();
- for (; first != d->chunks.end(); ++first)
- {
- if (first->good == false)
- d->iOffset += first->length;
- else
- {
- if (tagSize < first->length)
- {
- first->length -= tagSize;
- d->iOffset += tagSize;
- break;
- }
- else
- {
- tagSize -= first->length;
- d->iOffset += first->length;
- }
- }
- }
- d->chunks.erase(d->chunks.begin(), first);
- }
-
- Tag.Trim();
- 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 */
-static bool FillBuffer(pkgTagFilePrivate * const d)
-{
- unsigned long long Actual = 0;
- // See if only a bit of the file is left
- unsigned long long const dataSize = d->Size - ((d->End - d->Buffer) + 1);
- if (d->Fd->Read(d->End, dataSize, &Actual) == false)
- return false;
- if (Actual != dataSize)
- d->Done = true;
- d->End += Actual;
- return true;
-}
-static void RemoveCommentsFromBuffer(pkgTagFilePrivate * const d)
-{
- // look for valid comments in the buffer
- char * good_start = nullptr, * bad_start = nullptr;
- char * current = d->Start;
- if (d->isCommentedLine == false)
- {
- if (d->Start == d->Buffer)
- {
- // the start of the buffer is a newline as a record can't start
- // in the middle of a line by definition.
- if (*d->Start == '#')
- {
- d->isCommentedLine = true;
- ++current;
- if (current > d->End)
- d->chunks.emplace_back(false, 1);
- }
- }
- if (d->isCommentedLine == false)
- good_start = d->Start;
- else
- bad_start = d->Start;
- }
- else
- bad_start = d->Start;
-
- std::vector<std::pair<char*, size_t>> good_parts;
- while (current <= d->End)
- {
- size_t const restLength = (d->End - current);
- if (d->isCommentedLine == false)
- {
- current = static_cast<char*>(memchr(current, '#', restLength));
- if (current == nullptr)
- {
- size_t const goodLength = d->End - good_start;
- d->chunks.emplace_back(true, goodLength);
- if (good_start != d->Start)
- good_parts.push_back(std::make_pair(good_start, goodLength));
- break;
- }
- bad_start = current;
- --current;
- // ensure that this is really a comment and not a '#' in the middle of a line
- if (*current == '\n')
- {
- size_t const goodLength = (current - good_start) + 1;
- d->chunks.emplace_back(true, goodLength);
- good_parts.push_back(std::make_pair(good_start, goodLength));
- good_start = nullptr;
- d->isCommentedLine = true;
- }
- current += 2;
- }
- else // the current line is a comment
- {
- current = static_cast<char*>(memchr(current, '\n', restLength));
- if (current == nullptr)
- {
- d->chunks.emplace_back(false, (d->End - bad_start));
- break;
- }
- ++current;
- // is the next line a comment, too?
- if (current >= d->End || *current != '#')
- {
- d->chunks.emplace_back(false, (current - bad_start));
- good_start = current;
- bad_start = nullptr;
- d->isCommentedLine = false;
- }
- ++current;
- }
- }
-
- if (good_parts.empty() == false)
- {
- // we found comments, so move later parts over them
- current = d->Start;
- for (auto const &good: good_parts)
- {
- memmove(current, good.first, good.second);
- current += good.second;
- }
- d->End = current;
- }
-
- if (d->isCommentedLine == true)
- {
- // deal with a buffer containing only comments
- // or an (unfinished) comment at the end
- if (good_parts.empty() == true)
- d->End = d->Start;
- else
- d->Start = d->End;
- }
- else
- {
- // the buffer was all comment, but ended with the buffer
- if (good_parts.empty() == true && good_start >= d->End)
- d->End = d->Start;
- else
- d->Start = d->End;
- }
-}
-bool pkgTagFile::Fill()
-{
- unsigned long long const EndSize = d->End - d->Start;
- if (EndSize != 0)
- {
- memmove(d->Buffer,d->Start,EndSize);
- d->Start = d->End = d->Buffer + EndSize;
- }
- else
- d->Start = d->End = d->Buffer;
-
- unsigned long long Actual = 0;
- while (d->Done == false && d->Size > (Actual + 1))
- {
- if (FillBuffer(d) == false)
- return false;
- if ((d->Flags & pkgTagFile::SUPPORT_COMMENTS) != 0)
- RemoveCommentsFromBuffer(d);
- Actual = d->End - d->Buffer;
- }
- d->Start = d->Buffer;
-
- if (d->Done == true)
- {
- if (EndSize <= 3 && Actual == 0)
- return false;
- if (d->Size - (d->End - d->Buffer) < 4)
- return true;
-
- // Append a double new line if one does not exist
- unsigned int LineCount = 0;
- for (const char *E = d->End - 1; E - d->End < 6 && (*E == '\n' || *E == '\r'); E--)
- if (*E == '\n')
- ++LineCount;
- if (LineCount < 2)
- {
- if (static_cast<unsigned long long>(d->End - d->Buffer) >= d->Size)
- Resize(d->Size + 3);
- for (; LineCount < 2; ++LineCount)
- *d->End++ = '\n';
- }
- }
+ d->iOffset += tagSize;
return true;
}
/*}}}*/
@@ -428,43 +182,16 @@ bool pkgTagFile::Fill()
that is there */
bool pkgTagFile::Jump(pkgTagSection &Tag,unsigned long long Offset)
{
- if ((d->Flags & pkgTagFile::SUPPORT_COMMENTS) == 0 &&
- // We are within a buffer space of the next hit..
- Offset >= d->iOffset && d->iOffset + (d->End - d->Start) > Offset)
- {
- unsigned long long Dist = Offset - d->iOffset;
- d->Start += Dist;
- d->iOffset += Dist;
- // if we have seen the end, don't ask for more
- if (d->Done == true)
- return Tag.Scan(d->Start, d->End - d->Start);
- else
- return Step(Tag);
- }
+ unsigned int Size(d->Map->Size());
+ if (Offset >= Size)
+ return false;
// Reposition and reload..
d->iOffset = Offset;
d->Done = false;
- if (d->Fd->Seek(Offset) == false)
- return false;
- d->End = d->Start = d->Buffer;
- d->isCommentedLine = false;
- d->chunks.clear();
-
- if (Fill() == false)
- return false;
+ d->Start = d->Buffer + d->iOffset;
- if (Tag.Scan(d->Start, d->End - d->Start) == true)
- return true;
-
- // This appends a double new line (for the real eof handling)
- if (Fill() == false)
- return false;
-
- if (Tag.Scan(d->Start, d->End - d->Start, false) == false)
- return _error->Error(_("Unable to parse package file %s (%d)"),d->Fd->Name().c_str(), 2);
-
- return true;
+ return Step(Tag);
}
/*}}}*/
// pkgTagSection::pkgTagSection - Constructor /*{{{*/
@@ -480,32 +207,20 @@ pkgTagSection::pkgTagSection()
APT_IGNORE_DEPRECATED_POP
/*}}}*/
// TagSection::Scan - Scan for the end of the header information /*{{{*/
-bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength, bool const Restart)
+bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength,bool const SupportComments)
{
Section = Start;
const char *End = Start + MaxLength;
- if (Restart == false && d->Tags.empty() == false)
+ Stop = Section;
+ if (d->Tags.empty() == false)
{
- Stop = Section + d->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 (d->Tags.empty() == false)
- {
- memset(&AlphaIndexes, 0, sizeof(AlphaIndexes));
- memset(&BetaIndexes, 0, sizeof(BetaIndexes));
- d->Tags.clear();
- }
- d->Tags.reserve(0x100);
+ memset(&AlphaIndexes, 0, sizeof(AlphaIndexes));
+ memset(&BetaIndexes, 0, sizeof(BetaIndexes));
+ d->Tags.clear();
}
+ d->Tags.reserve(0x100);
+
unsigned int TagCount = d->Tags.size();
if (Stop == 0)
@@ -517,12 +232,12 @@ bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength, bool const R
unsigned int lastTagHash = 0;
while (Stop < End)
{
- TrimRecord(true,End);
+ TrimRecord(true,End,SupportComments);
// this can happen when TrimRecord trims away the entire Record
// (e.g. because it just contains comments)
if(Stop == End)
- return true;
+ goto end;
// Start a new index and add it to the hash
if (isspace_ascii(Stop[0]) == 0)
@@ -570,8 +285,10 @@ bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength, bool const R
Stop = (const char *)memchr(Stop,'\n',End - Stop);
- if (Stop == 0)
- return false;
+ if (Stop == 0) {
+ Stop = End;
+ goto end;
+ }
for (; Stop+1 < End && Stop[1] == '\r'; Stop++)
/* nothing */
@@ -579,7 +296,7 @@ bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength, bool const R
// Double newline marks the end of the record
if (Stop+1 < End && Stop[1] == '\n')
- {
+ end: {
if (lastTagData.EndTag != 0)
{
if (lastTagKey != Key::Unknown) {
@@ -592,34 +309,32 @@ bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength, bool const R
d->Tags.push_back(lastTagData);
}
+ if (d->Tags.empty())
+ return false;
+
pkgTagSectionPrivate::TagData const td(Stop - Section);
d->Tags.push_back(td);
- TrimRecord(false,End);
+ TrimRecord(false,End,SupportComments);
return true;
}
Stop++;
}
- return false;
+ goto end;
}
/*}}}*/
// TagSection::TrimRecord - Trim off any garbage before/after a record /*{{{*/
// ---------------------------------------------------------------------
/* There should be exactly 2 newline at the end of the record, no more. */
-void pkgTagSection::TrimRecord(bool BeforeRecord, const char*& End)
-{
- if (BeforeRecord == true)
- return;
- for (; Stop < End && (Stop[0] == '\n' || Stop[0] == '\r'); Stop++);
-}
- /*}}}*/
-// TagSection::Trim - Trim off any trailing garbage /*{{{*/
-// ---------------------------------------------------------------------
-/* There should be exactly 1 newline at the end of the buffer, no more. */
-void pkgTagSection::Trim()
-{
- for (; Stop > Section + 2 && (Stop[-2] == '\n' || Stop[-2] == '\r'); Stop--);
+void pkgTagSection::TrimRecord(bool BeforeRecord, const char*& End, bool SupportComments)
+{ trim:
+ if (BeforeRecord == false)
+ for (; Stop < End && (Stop[0] == '\n' || Stop[0] == '\r'); Stop++);
+ if (SupportComments && Stop < End && Stop[0] == '#') {
+ Stop = (const char*) memchr(Stop,'\n',End-Stop) ?: End;
+ goto trim;
+ }
}
/*}}}*/
// TagSection::Exists - return True if a tag exists /*{{{*/
@@ -1062,14 +777,6 @@ bool pkgTagSection::Write(FileFd &File, char const * const * const Order, std::v
}
/*}}}*/
-void pkgUserTagSection::TrimRecord(bool /*BeforeRecord*/, const char* &End)/*{{{*/
-{
- for (; Stop < End && (Stop[0] == '\n' || Stop[0] == '\r' || Stop[0] == '#'); Stop++)
- if (Stop[0] == '#')
- Stop = (const char*) memchr(Stop,'\n',End-Stop);
-}
- /*}}}*/
-
#include "tagfile-order.c"
// TFRewrite - Rewrite a control record /*{{{*/