/*
* Copyright 1995, 1996 Perforce Software. All rights reserved.
*
* This file is part of the Library RCS. See rcstest.c.
*/
/*
* diffmerge.h - 3 way file merge
*
* Classes defined:
*
* DiffMerge - control block for merging
*
* Public methods:
*
* DiffMerge::DiffMerge() - Merge 3 files to produce integrated result
* DiffMerge::~DiffMerge() - dispose of DiffMerge and its contents
* DiffMerge::Read() - produce next part of integrated result
*
* History:
* 2-18-97 (seiwald) - translated to C++.
*/
/*
* SELBITS - the return value from DiffMergeRead
*
* 0 means no more output; otherwise the bits are set according to what
* outputfile is to take the next piece. The length of DiffMergeRead
* can be zero while the bits returned are non-zero: this indicates a
* zero length chunk to be placed in the output file.
*
* SEL_CONF indicates a conflict, and is set for each of the legs that
* are in conflict, including the base. Thus for a conflict the follow
* sequence will be seen:
*
* SEL_CONF | SEL_BASE
* SEL_CONF | SEL_LEG1 | SEL_RSLT
* SEL_CONF | SEL_LEG2 | SEL_RSLT
*
* If changes are identical both lines, they are not in conflict. The
* sequence is:
*
* SEL_BASE
* SEL_LEG1 | SEL_LEG2 | SEL_RSLT
*
* SEL_ALL indicates chunks synchronized between all 3 files. The
* actual text comes from LEG2, so that if the underlying diff is
* ignoring certain changes (like whitespace), the resulting merge
* will have the last leg (typically "yours") rather than the original
* unchanged base.
*/
# define SEL_BASE 0x01
# define SEL_LEG1 0x02
# define SEL_LEG2 0x04
# define SEL_RSLT 0x08
# define SEL_ALL (SEL_BASE|SEL_LEG1|SEL_LEG2|SEL_RSLT)
# define SEL_CONF 0x10
class DiffAnalyze;
class DiffDFile;
class DiffFfile;
class DiffFlags;
enum DiffDiffs {
DD_EOF, // End of df1/df2
DD_LEG1, // df1 up next
DD_LEG2, // df2 up next
DD_BOTH, // df1, df2 overlap
DD_CONF, // df1, df2 conflict
DD_ALL, // all lines
DD_LAST
} ;
enum GridTypes {
GRT_OPTIMAL, // Optimal grid type
GRT_GUARDED, // Guarded grid type
GRT_TWOWAY // Two way grid type
} ;
typedef offL_t LineLen;
class DiffMerge {
public:
DiffMerge( FileSys *base, FileSys *leg1, FileSys *leg2,
const DiffFlags &fl, LineType lineType, Error *e );
~DiffMerge();
int Read( char *buf, int len, int *outlen );
const char *BitNames( int bits );
LineLen MaxLineLength() const;
private:
DiffDiffs DiffDiff();
/* State machine for merging. */
DiffDiffs diffDiff;
GridTypes gridType;
int twoWay;
int state;
/* Base->Yours diff, Base->Theirs diff. */
DiffDFile *df1;
DiffDFile *df2;
DiffDFile *df3;
/* Base, yours, theirs. */
DiffFfile *bf;
DiffFfile *lf1;
DiffFfile *lf2;
/* Empty base */
FileSys *emptyFile;
/*
* For returning data from Read():
* what leg we're reading from,
* what selbits we're returning
*/
DiffFfile *readFile;
int selbits;
} ;