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|
z1 = &blob_buffer(pV1)[blob_tell(pV1)];
z2 = &blob_buffer(pV2)[blob_tell(pV2)];
for(i=0; z1[i]!='\n' && z1[i]==z2[i]; i++){}
return z2[i]=='\n' || (z2[i]=='\r' && z2[i+1]=='\n')
|| (z1[i]=='\r' && z2[i]=='\n' && z1[i+1]=='\n');
}
/* The minimum of two integers */
#define min(A,B) (A<B?A:B)
/*
** Do a three-way merge. Initialize pOut to contain the result.
**
** The merge is an edit against pV2. Both pV1 and pV2 have a
** common origin at pPivot. Apply the changes of pPivot ==> pV1
** to pV2.
**
** The return is 0 upon complete success. If any input file is binary,
** -1 is returned and pOut is unmodified. If there are merge
** conflicts, the merge proceeds as best as it can and the number
** of conflicts is returns
*/
int blob_merge(Blob *pPivot, Blob *pV1, Blob *pV2, Blob *pOut){
int *aC1; /* Changes from pPivot to pV1 */
int *aC2; /* Changes from pPivot to pV2 */
int i1, i2;
int op1, op2;
int limit1, limit2;
int *aC1; /* Changes from pPivot to pV1 */
int *aC2; /* Changes from pPivot to pV2 */
int i1, i2; /* Index into aC1[] and aC2[] */
int op1, op2; /* Opcode for aC1[] and aC2[] */
int n1, n2; /* Counts for op1 and op2 */
int mn; /* Minimum count of op1 and op2 */
int limit1, limit2; /* Sizes of aC1[] and aC2[] */
int inConflict = 0;
int nConflict = 0;
static const char zBegin[] = ">>>>>>>> BEGIN MERGE CONFLICT <<<<<<<<\n";
static const char zEnd[] = ">>>>>>>>> END MERGE CONFLICT <<<<<<<<<\n";
blob_zero(pOut);
blob_rewind(pV1);
blob_zero(pOut); /* Merge results stored in pOut */
blob_rewind(pV1); /* Rewind inputs: Needed to reconstruct output */
blob_rewind(pV2);
blob_rewind(pPivot);
/* Determine the length of the aC1[] and aC2[] change vectors */
for(i1=0; aC1[i1] || aC1[i1+1] || aC1[i1+2]; i1+=3){}
limit1 = i1;
for(i2=0; aC2[i2] || aC2[i2+1] || aC2[i2+2]; i2+=3){}
limit2 = i2;
DEBUG(
for(i1=0; i1<limit1; i1+=3){
printf("c1: %4d %4d %4d\n", aC1[i1], aC1[i1+1], aC1[i1+2]);
}
for(i2=0; i2<limit2; i2+=3){
printf("c2: %4d %4d %4d\n", aC2[i2], aC2[i2+1], aC2[i2+2]);
}
)
op1 = op2 = UNK;
i1 = i2 = 0;
i1 = i2 = -1;
while( i1<limit1 && aC1[i1]==0 ){ i1++; }
while( i2<limit2 && aC2[i2]==0 ){ i2++; }
if( i1>=limit1 ){
op1 = END;
if( i1>=limit1 ){
op1 = END;
DEBUG( printf("get op1=END\n"); )
}else{
op1 = i1 % 3;
aC1[i1]--;
DEBUG( printf("get op1=%d from %d (%d->%d)\n",
op1,i1,aC1[i1]+1,aC1[i1]); )
while( i1<limit1 && aC1[i1]==0 ){ i1++; }
if( i2>=limit2 ){
op2 = END;
if( i2>=limit2 ){
op2 = END;
DEBUG( printf("get op2=END\n"); )
}else{
op2 = i2 % 3;
aC2[i2]--;
DEBUG( printf("get op2=%d from %d (%d->%d)\n",
op2,i2,aC2[i2]+1,aC2[i2]); )
while( i2<limit2 && aC2[i2]==0 ){ i2++; }
}
}
DEBUG( printf("op1=%d op2=%d\n", op1, op2); )
blob_copy_lines(pOut, pV2, 1);
blob_copy_lines(pOut, pV2, n2);
op2 = UNK;
}else{
break;
blob_copy_lines(pOut, pV1, 1);
blob_copy_lines(pOut, pV1, n1);
op1 = UNK;
}else{
break;
}
}else if( op1==INS && op2==INS ){
if( !inConflict && sameLine(pV1, pV2) ){
blob_copy_lines(pOut, pV2, 1);
blob_copy_lines(0, pV1, 0);
op1 = UNK;
op2 = UNK;
}else{
if( !inConflict ){
inConflict = 1;
nConflict++;
blob_appendf(pOut, zBegin);
}
blob_copy_lines(pOut, pV1, 1);
op1 = UNK;
}
}else if( op1==INS ){
blob_copy_lines(pOut, pV1, 1);
op1 = UNK;
}else if( op2==INS ){
blob_copy_lines(pOut, pV2, 1);
op2 = UNK;
if( inConflict ){
inConflict = 0;
blob_appendf(pOut, zEnd);
int toSkip = 0;
nConflict++;
DEBUG( printf("CONFLICT\n"); )
blob_appendf(pOut, zBegin);
}
if( op1==DEL || op2==DEL ){
blob_copy_lines(0, pPivot, 1);
if( op2==CPY ){
blob_copy_lines(0, pV2, 1);
}
if( op1==CPY ){
blob_copy_lines(0, pV1, 1);
assert( op1==CPY && op2==CPY );
blob_copy_lines(pOut, pPivot, 1);
blob_copy_lines(0, pV1, 1);
blob_copy_lines(0, pV2, 1);
}
op1 = UNK;
op2 = UNK;
}
}
if( inConflict ){
blob_appendf(pOut, zEnd);
|