/*
** 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; /* Index into aC1[] and aC2[] */
int nCpy, nDel, nIns; /* Number of lines to copy, delete, or insert */
int limit1, limit2; /* Sizes of aC1[] and aC2[] */
int nConflict = 0; /* Number of merge conflicts seen so far */
static const char zBegin[] =
"<<<<<<< BEGIN MERGE CONFLICT: local copy shown first <<<<<<<<<<<<<<<\n";
static const char zMid1[] =
"======= COMMON ANCESTOR content follows ============================\n";
static const char zMid2[] =
"======= MERGED IN content follows ==================================\n";
static const char zEnd[] =
">>>>>>> END MERGE CONFLICT >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n";
blob_zero(pOut); /* Merge results stored in pOut */
/* Compute the edits that occur from pPivot => pV1 (into aC1)
** and pPivot => pV2 (into aC2). Each of the aC1 and aC2 arrays is
** an array of integer triples. Within each triple, the first integer
** is the number of lines of text to copy directly from the pivot,
** the second integer is the number of lines of text to omit from the
** pivot, and the third integer is the number of lines of text that are
** inserted. The edit array ends with a triple of 0,0,0.
*/
aC1 = text_diff(pPivot, pV1, 0, 0);
aC2 = text_diff(pPivot, pV2, 0, 0);
if( aC1==0 || aC2==0 ){
free(aC1);
free(aC2);
return -1;
}
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]);
}
)
/*
** Show the difference between two files, both in memory.
**
** The difference is the set of edits needed to transform pFile1 into
** pFile2.
**
** Use the internal diff logic if zDiffCmd is NULL. Otherwise call the
** command zDiffCmd to do the diffing.
*/
static void diff_file_mem(
Blob *pFile1, /* In memory content to compare from */
Blob *pFile2, /* In memory content to compare to */
const char *zName, /* Display name of the file */
const char *zDiffCmd, /* Command for comparison */
int ignoreEolWs /* Ignore whitespace at end of lines */
){
if( zDiffCmd==0 ){
Blob out; /* Diff output text */
blob_zero(&out);
text_diff(pFile1, pFile2, &out, 5, ignoreEolWs);
printf("--- %s\n+++ %s\n", zName, zName);
printf("%s\n", blob_str(&out));
/* Release memory resources */
blob_reset(&out);
}else{
Blob cmd;
char zTemp1[300];
char zTemp2[300];
/* Construct a temporary file names */
file_tempname(sizeof(zTemp1), zTemp1);
file_tempname(sizeof(zTemp2), zTemp2);
blob_write_to_file(pFile1, zTemp1);
blob_write_to_file(pFile2, zTemp2);
/* Construct the external diff command */
blob_zero(&cmd);
blob_appendf(&cmd, "%s ", zDiffCmd);
shell_escape(&cmd, zTemp1);
blob_append(&cmd, " ", 1);
shell_escape(&cmd, zTemp2);
/* Run the external diff command */
portable_system(blob_str(&cmd));
/* Delete the temporary file and clean up memory used */
unlink(zTemp1);
unlink(zTemp2);
blob_reset(&cmd);
}
}
/*
** Generates a diff between two versions (zFrom and zTo), using nContext
** content lines in the output. On success, returns a new JSON String
** object. On error it sets g.json's error state and returns NULL.
**
** If fSbs is true (non-0) them side-by-side diffs are used.
**
** If fHtml is true then HTML markup is added to the diff.
*/
cson_value * json_generate_diff(const char *zFrom, const char *zTo,
int nContext, char fSbs,
char fHtml){
int fromid;
int toid;
int outLen;
Blob from = empty_blob, to = empty_blob, out = empty_blob;
cson_value * rc = NULL;
int flags = (DIFF_CONTEXT_MASK & nContext)
| (fSbs ? DIFF_SIDEBYSIDE : 0)
| (fHtml ? DIFF_HTML : 0);
fromid = name_to_typed_rid(zFrom, "*");
if(fromid<=0){
json_set_err(FSL_JSON_E_UNRESOLVED_UUID,
"Could not resolve 'from' ID.");
return NULL;
}
toid = name_to_typed_rid(zTo, "*");
if(toid<=0){
json_set_err(FSL_JSON_E_UNRESOLVED_UUID,
"Could not resolve 'to' ID.");
return NULL;
}
content_get(fromid, &from);
content_get(toid, &to);
blob_zero(&out);
text_diff(&from, &to, &out, 0, flags);
blob_reset(&from);
blob_reset(&to);
outLen = blob_size(&out);
if(outLen>=0){
rc = cson_value_new_string(blob_buffer(&out),
(unsigned int)blob_size(&out));
}
blob_reset(&out);
return rc;
}
/*
** 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
*/
static int
sbuf_merge(char *pPivot, char *pV1, char *pV2, struct sbuf *pOut){
int *aC1; /* Changes from pPivot to pV1 */
int *aC2; /* Changes from pPivot to pV2 */
int i1, i2; /* Index into aC1[] and aC2[] */
int nCpy, nDel, nIns; /* Number of lines to copy, delete, or insert */
int limit1, limit2; /* Sizes of aC1[] and aC2[] */
int nConflict = 0; /* Number of merge conflicts seen so far */
sbuf_clear(pOut); /* Merge results stored in pOut */
/* Compute the edits that occur from pPivot => pV1 (into aC1)
** and pPivot => pV2 (into aC2). Each of the aC1 and aC2 arrays is
** an array of integer triples. Within each triple, the first integer
** is the number of lines of text to copy directly from the pivot,
** the second integer is the number of lines of text to omit from the
** pivot, and the third integer is the number of lines of text that are
** inserted. The edit array ends with a triple of 0,0,0.
*/
aC1 = text_diff(pPivot, pV1);
aC2 = text_diff(pPivot, pV2);
if( aC1==0 || aC2==0 ){
free(aC1);
free(aC2);
return -1;
}
/* 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;
/* Loop over the two edit vectors and use them to compute merged text
** which is written into pOut. i1 and i2 are multiples of 3 which are
** indices into aC1[] and aC2[] to the edit triple currently being
** processed
*/
i1 = i2 = 0;
while( i1<limit1 && i2<limit2 ){
if( aC1[i1]>0 && aC2[i2]>0 ){
/* Output text that is unchanged in both V1 and V2 */
nCpy = min(aC1[i1], aC2[i2]);
pPivot += sbuf_copy_lines(pOut, pPivot, nCpy);
pV1 += sbuf_copy_lines(NULL, pV1, nCpy);
pV2 += sbuf_copy_lines(NULL, pV2, nCpy);
aC1[i1] -= nCpy;
aC2[i2] -= nCpy;
}else
if( aC1[i1] >= aC2[i2+1] && aC1[i1]>0 && aC2[i2+1]+aC2[i2+2]>0 ){
/* Output edits to V2 that occurs within unchanged regions of V1 */
nDel = aC2[i2+1];
nIns = aC2[i2+2];
pPivot += sbuf_copy_lines(NULL, pPivot, nDel);
pV1 += sbuf_copy_lines(NULL, pV1, nDel);
pV2 += sbuf_copy_lines(pOut, pV2, nIns);
aC1[i1] -= nDel;
i2 += 3;
}else
if( aC2[i2] >= aC1[i1+1] && aC2[i2]>0 && aC1[i1+1]+aC1[i1+2]>0 ){
/* Output edits to V1 that occur within unchanged regions of V2 */
nDel = aC1[i1+1];
nIns = aC1[i1+2];
pPivot += sbuf_copy_lines(NULL, pPivot, nDel);
pV2 += sbuf_copy_lines(NULL, pV2, nDel);
pV1 += sbuf_copy_lines(pOut, pV1, nIns);
aC2[i2] -= nDel;
i1 += 3;
}else
if( sameEdit(&aC1[i1], &aC2[i2], pV1, pV2) ){
/* Output edits that are identical in both V1 and V2. */
nDel = aC1[i1+1];
nIns = aC1[i1+2];
pPivot += sbuf_copy_lines(NULL, pPivot, nDel);
pV1 += sbuf_copy_lines(pOut, pV1, nIns);
pV2 += sbuf_copy_lines(NULL, pV2, nIns);
i1 += 3;
i2 += 3;
}else
{
return (-1);
}
/* If we are finished with an edit triple, advance to the next
** triple.
*/
if( i1<limit1 && aC1[i1]==0 && aC1[i1+1]==0 && aC1[i1+2]==0 ) i1+=3;
if( i2<limit2 && aC2[i2]==0 && aC2[i2+1]==0 && aC2[i2+2]==0 ) i2+=3;
}
/* When one of the two edit vectors reaches its end, there might still
** be an insert in the other edit vector. Output this remaining
** insert.
*/
if( i1<limit1 && aC1[i1+2]>0 ){
sbuf_copy_lines(pOut, pV1, aC1[i1+2]);
}else if( i2<limit2 && aC2[i2+2]>0 ){
sbuf_copy_lines(pOut, pV2, aC2[i2+2]);
}
free(aC1);
free(aC2);
return nConflict;
}
