// -*- mode: cpp; mode: fold -*-
// Description /*{{{*/
-// $Id: tagfile.cc,v 1.11 1998/10/02 04:39:48 jgg Exp $
+// $Id: tagfile.cc,v 1.21 1999/01/31 07:01:11 jgg Exp $
/* ######################################################################
Fast scanner for RFC-822 type header information
#include <apt-pkg/tagfile.h>
#include <apt-pkg/error.h>
+#include <apt-pkg/strutl.h>
#include <string>
#include <stdio.h>
return false;
if (Tag.Scan(Start,End - Start) == false)
- {
- cout << string(Start,End-Start) << endl;
- return _error->Error("Unable to parse package file");
- }
+ return _error->Error("Unable to parse package file %s",Fd.Name().c_str());
}
Start += Tag.size();
iOffset += Tag.size();
{
unsigned long EndSize = End - Start;
+ memmove(Buffer,Start,EndSize);
+ Start = Buffer;
+ End = Buffer + EndSize;
+
if (Left == 0)
{
- if (EndSize <= 1)
+ if (EndSize <= 3)
return false;
+ if (Size - (End - Buffer) < 4)
+ return true;
+
+ // Append a double new line if one does not exist
+ unsigned int LineCount = 0;
+ for (const char *E = End - 1; E - End < 6 && (*E == '\n' || *E == '\r'); E--)
+ if (*E == '\n')
+ LineCount++;
+ for (; LineCount < 2; LineCount++)
+ *End++ = '\n';
+
return true;
}
- memmove(Buffer,Start,EndSize);
- Start = Buffer;
- End = Buffer + EndSize;
-
- // See if only a bit of the file is left
- if (Left < Size)
+ // See if only a bit of the file is left
+ if (Left < Size - (End - Buffer))
{
if (Fd.Read(End,Left) == false)
return false;
+
End += Left;
Left = 0;
}
{
if (Fd.Read(End,Size - (End - Buffer)) == false)
return false;
+
Left -= Size - (End - Buffer);
End = Buffer + Size;
}
/*}}}*/
// TagFile::Jump - Jump to a pre-recorded location in the file /*{{{*/
// ---------------------------------------------------------------------
-/* This jumps to a pre-recorded file location and */
+/* This jumps to a pre-recorded file location and reads the record
+ that is there */
bool pkgTagFile::Jump(pkgTagSection &Tag,unsigned long Offset)
{
iOffset = Offset;
// 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. */
+ indexes the tags in the section. This very simple hash function for the
+ first 3 letters gives very good performance on the debian package files */
bool pkgTagSection::Scan(const char *Start,unsigned long MaxLength)
{
const char *End = Start + MaxLength;
Stop = Section = Start;
+ memset(AlphaIndexes,0,sizeof(AlphaIndexes));
+
+ if (Stop == 0)
+ return false;
TagCount = 0;
- Indexes[TagCount++] = Stop - Section;
- Stop++;
- for (; Stop < End; Stop++)
+ while (TagCount < sizeof(Indexes)/sizeof(Indexes[0]))
{
- if (Stop[-1] != '\n')
- continue;
+ // Start a new index and add it to the hash
+ if (isspace(Stop[0]) == 0)
+ {
+ Indexes[TagCount++] = Stop - Section;
+ unsigned char A = tolower(Stop[0]) - 'a';
+ unsigned char B = tolower(Stop[1]) - 'a';
+ unsigned char C = tolower(Stop[3]) - 'a';
+ AlphaIndexes[((A + C/3)%26) + 26*((B + C/2)%26)] = TagCount;
+ }
- // Skip line feeds
- for (; Stop[0] == '\r' && Stop < End; Stop++);
+ Stop = (const char *)memchr(Stop,'\n',End - Stop);
- if (Stop[0] == '\n')
+ if (Stop == 0)
+ return false;
+ for (; Stop[1] == '\r' && Stop+1 < End; Stop++);
+
+ // Double newline or end of file marks the end of the record
+ if (Stop+1 >= End || Stop[1] == '\n')
{
- // Extra one at the end to simplify find
Indexes[TagCount] = Stop - Section;
for (; (Stop[0] == '\n' || Stop[0] == '\r') && Stop < End; Stop++);
return true;
}
- 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]);
- }
+ Stop++;
+ }
+
return false;
}
/*}}}*/
const char *&End)
{
unsigned int Length = strlen(Tag);
- for (unsigned int I = 0; I != TagCount; I++)
+ unsigned char A = tolower(Tag[0]) - 'a';
+ unsigned char B = tolower(Tag[1]) - 'a';
+ unsigned char C = tolower(Tag[3]) - 'a';
+ unsigned int I = AlphaIndexes[((A + C/3)%26) + 26*((B + C/2)%26)];
+ if (I == 0)
+ return false;
+ I--;
+
+ for (unsigned int Counter = 0; Counter != TagCount; Counter++,
+ I = (I+1)%TagCount)
{
- if (strncasecmp(Tag,Section + Indexes[I],Length) != 0)
+ 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 = Section + Length + Indexes[I];
+ const char *C = St + Length;
for (; isspace(*C) != 0; C++);
if (*C != ':')
continue;
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;
}
/*}}}*/
+// TagSection::FindS - Find a string /*{{{*/
+// ---------------------------------------------------------------------
+/* */
+string pkgTagSection::FindS(const char *Tag)
+{
+ const char *Start;
+ const char *End;
+ if (Find(Tag,Start,End) == false)
+ return string();
+ return string(Start,End);
+}
+ /*}}}*/
+// TagSection::FindI - Find an integer /*{{{*/
+// ---------------------------------------------------------------------
+/* */
+signed int pkgTagSection::FindI(const char *Tag,signed long Default)
+{
+ const char *Start;
+ const char *Stop;
+ if (Find(Tag,Start,Stop) == false)
+ return Default;
+
+ // Copy it into a temp buffer so we can use strtol
+ char S[300];
+ if ((unsigned)(Stop - Start) >= sizeof(S))
+ return Default;
+ strncpy(S,Start,Stop-Start);
+ S[Stop - Start] = 0;
+
+ char *End;
+ signed long Result = strtol(S,&End,10);
+ if (S == End)
+ return Default;
+ return Result;
+}
+ /*}}}*/
+// TagSection::FindFlag - Locate a yes/no type flag /*{{{*/
+// ---------------------------------------------------------------------
+/* The bits marked in Flag are masked on/off in Flags */
+bool pkgTagSection::FindFlag(const char *Tag,unsigned long &Flags,
+ unsigned long Flag)
+{
+ const char *Start;
+ const char *Stop;
+ if (Find(Tag,Start,Stop) == false)
+ return true;
+
+ switch (StringToBool(string(Start,Stop)))
+ {
+ case 0:
+ Flags &= ~Flag;
+ return true;
+
+ case 1:
+ Flags |= Flag;
+ return true;
+
+ default:
+ _error->Warning("Unknown flag value");
+ return true;
+ }
+ return true;
+}
+ /*}}}*/
+
+
projects / apt.git / blobdiff