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-rw-r--r--combine-diff.c1395
1 files changed, 1395 insertions, 0 deletions
diff --git a/combine-diff.c b/combine-diff.c
new file mode 100644
index 0000000..6dc0609
--- /dev/null
+++ b/combine-diff.c
@@ -0,0 +1,1395 @@
+#include "cache.h"
+#include "commit.h"
+#include "blob.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "quote.h"
+#include "xdiff-interface.h"
+#include "xdiff/xmacros.h"
+#include "log-tree.h"
+#include "refs.h"
+#include "userdiff.h"
+#include "sha1-array.h"
+
+static struct combine_diff_path *intersect_paths(struct combine_diff_path *curr, int n, int num_parent)
+{
+ struct diff_queue_struct *q = &diff_queued_diff;
+ struct combine_diff_path *p;
+ int i;
+
+ if (!n) {
+ struct combine_diff_path *list = NULL, **tail = &list;
+ for (i = 0; i < q->nr; i++) {
+ int len;
+ const char *path;
+ if (diff_unmodified_pair(q->queue[i]))
+ continue;
+ path = q->queue[i]->two->path;
+ len = strlen(path);
+ p = xmalloc(combine_diff_path_size(num_parent, len));
+ p->path = (char *) &(p->parent[num_parent]);
+ memcpy(p->path, path, len);
+ p->path[len] = 0;
+ p->len = len;
+ p->next = NULL;
+ memset(p->parent, 0,
+ sizeof(p->parent[0]) * num_parent);
+
+ hashcpy(p->sha1, q->queue[i]->two->sha1);
+ p->mode = q->queue[i]->two->mode;
+ hashcpy(p->parent[n].sha1, q->queue[i]->one->sha1);
+ p->parent[n].mode = q->queue[i]->one->mode;
+ p->parent[n].status = q->queue[i]->status;
+ *tail = p;
+ tail = &p->next;
+ }
+ return list;
+ }
+
+ for (p = curr; p; p = p->next) {
+ int found = 0;
+ if (!p->len)
+ continue;
+ for (i = 0; i < q->nr; i++) {
+ const char *path;
+ int len;
+
+ if (diff_unmodified_pair(q->queue[i]))
+ continue;
+ path = q->queue[i]->two->path;
+ len = strlen(path);
+ if (len == p->len && !memcmp(path, p->path, len)) {
+ found = 1;
+ hashcpy(p->parent[n].sha1, q->queue[i]->one->sha1);
+ p->parent[n].mode = q->queue[i]->one->mode;
+ p->parent[n].status = q->queue[i]->status;
+ break;
+ }
+ }
+ if (!found)
+ p->len = 0;
+ }
+ return curr;
+}
+
+/* Lines lost from parent */
+struct lline {
+ struct lline *next, *prev;
+ int len;
+ unsigned long parent_map;
+ char line[FLEX_ARRAY];
+};
+
+/* Lines lost from current parent (before coalescing) */
+struct plost {
+ struct lline *lost_head, *lost_tail;
+ int len;
+};
+
+/* Lines surviving in the merge result */
+struct sline {
+ /* Accumulated and coalesced lost lines */
+ struct lline *lost;
+ int lenlost;
+ struct plost plost;
+ char *bol;
+ int len;
+ /* bit 0 up to (N-1) are on if the parent has this line (i.e.
+ * we did not change it).
+ * bit N is used for "interesting" lines, including context.
+ * bit (N+1) is used for "do not show deletion before this".
+ */
+ unsigned long flag;
+ unsigned long *p_lno;
+};
+
+static int match_string_spaces(const char *line1, int len1,
+ const char *line2, int len2,
+ long flags)
+{
+ if (flags & XDF_WHITESPACE_FLAGS) {
+ for (; len1 > 0 && XDL_ISSPACE(line1[len1 - 1]); len1--);
+ for (; len2 > 0 && XDL_ISSPACE(line2[len2 - 1]); len2--);
+ }
+
+ if (!(flags & (XDF_IGNORE_WHITESPACE | XDF_IGNORE_WHITESPACE_CHANGE)))
+ return (len1 == len2 && !memcmp(line1, line2, len1));
+
+ while (len1 > 0 && len2 > 0) {
+ len1--;
+ len2--;
+ if (XDL_ISSPACE(line1[len1]) || XDL_ISSPACE(line2[len2])) {
+ if ((flags & XDF_IGNORE_WHITESPACE_CHANGE) &&
+ (!XDL_ISSPACE(line1[len1]) || !XDL_ISSPACE(line2[len2])))
+ return 0;
+
+ for (; len1 > 0 && XDL_ISSPACE(line1[len1]); len1--);
+ for (; len2 > 0 && XDL_ISSPACE(line2[len2]); len2--);
+ }
+ if (line1[len1] != line2[len2])
+ return 0;
+ }
+
+ if (flags & XDF_IGNORE_WHITESPACE) {
+ /* Consume remaining spaces */
+ for (; len1 > 0 && XDL_ISSPACE(line1[len1 - 1]); len1--);
+ for (; len2 > 0 && XDL_ISSPACE(line2[len2 - 1]); len2--);
+ }
+
+ /* We matched full line1 and line2 */
+ if (!len1 && !len2)
+ return 1;
+
+ return 0;
+}
+
+enum coalesce_direction { MATCH, BASE, NEW };
+
+/* Coalesce new lines into base by finding LCS */
+static struct lline *coalesce_lines(struct lline *base, int *lenbase,
+ struct lline *new, int lennew,
+ unsigned long parent, long flags)
+{
+ int **lcs;
+ enum coalesce_direction **directions;
+ struct lline *baseend, *newend = NULL;
+ int i, j, origbaselen = *lenbase;
+
+ if (new == NULL)
+ return base;
+
+ if (base == NULL) {
+ *lenbase = lennew;
+ return new;
+ }
+
+ /*
+ * Coalesce new lines into base by finding the LCS
+ * - Create the table to run dynamic programing
+ * - Compute the LCS
+ * - Then reverse read the direction structure:
+ * - If we have MATCH, assign parent to base flag, and consume
+ * both baseend and newend
+ * - Else if we have BASE, consume baseend
+ * - Else if we have NEW, insert newend lline into base and
+ * consume newend
+ */
+ lcs = xcalloc(origbaselen + 1, sizeof(int*));
+ directions = xcalloc(origbaselen + 1, sizeof(enum coalesce_direction*));
+ for (i = 0; i < origbaselen + 1; i++) {
+ lcs[i] = xcalloc(lennew + 1, sizeof(int));
+ directions[i] = xcalloc(lennew + 1, sizeof(enum coalesce_direction));
+ directions[i][0] = BASE;
+ }
+ for (j = 1; j < lennew + 1; j++)
+ directions[0][j] = NEW;
+
+ for (i = 1, baseend = base; i < origbaselen + 1; i++) {
+ for (j = 1, newend = new; j < lennew + 1; j++) {
+ if (match_string_spaces(baseend->line, baseend->len,
+ newend->line, newend->len, flags)) {
+ lcs[i][j] = lcs[i - 1][j - 1] + 1;
+ directions[i][j] = MATCH;
+ } else if (lcs[i][j - 1] >= lcs[i - 1][j]) {
+ lcs[i][j] = lcs[i][j - 1];
+ directions[i][j] = NEW;
+ } else {
+ lcs[i][j] = lcs[i - 1][j];
+ directions[i][j] = BASE;
+ }
+ if (newend->next)
+ newend = newend->next;
+ }
+ if (baseend->next)
+ baseend = baseend->next;
+ }
+
+ for (i = 0; i < origbaselen + 1; i++)
+ free(lcs[i]);
+ free(lcs);
+
+ /* At this point, baseend and newend point to the end of each lists */
+ i--;
+ j--;
+ while (i != 0 || j != 0) {
+ if (directions[i][j] == MATCH) {
+ baseend->parent_map |= 1<<parent;
+ baseend = baseend->prev;
+ newend = newend->prev;
+ i--;
+ j--;
+ } else if (directions[i][j] == NEW) {
+ struct lline *lline;
+
+ lline = newend;
+ /* Remove lline from new list and update newend */
+ if (lline->prev)
+ lline->prev->next = lline->next;
+ else
+ new = lline->next;
+ if (lline->next)
+ lline->next->prev = lline->prev;
+
+ newend = lline->prev;
+ j--;
+
+ /* Add lline to base list */
+ if (baseend) {
+ lline->next = baseend->next;
+ lline->prev = baseend;
+ if (lline->prev)
+ lline->prev->next = lline;
+ }
+ else {
+ lline->next = base;
+ base = lline;
+ }
+ (*lenbase)++;
+
+ if (lline->next)
+ lline->next->prev = lline;
+
+ } else {
+ baseend = baseend->prev;
+ i--;
+ }
+ }
+
+ newend = new;
+ while (newend) {
+ struct lline *lline = newend;
+ newend = newend->next;
+ free(lline);
+ }
+
+ for (i = 0; i < origbaselen + 1; i++)
+ free(directions[i]);
+ free(directions);
+
+ return base;
+}
+
+static char *grab_blob(const unsigned char *sha1, unsigned int mode,
+ unsigned long *size, struct userdiff_driver *textconv,
+ const char *path)
+{
+ char *blob;
+ enum object_type type;
+
+ if (S_ISGITLINK(mode)) {
+ blob = xmalloc(100);
+ *size = snprintf(blob, 100,
+ "Subproject commit %s\n", sha1_to_hex(sha1));
+ } else if (is_null_sha1(sha1)) {
+ /* deleted blob */
+ *size = 0;
+ return xcalloc(1, 1);
+ } else if (textconv) {
+ struct diff_filespec *df = alloc_filespec(path);
+ fill_filespec(df, sha1, 1, mode);
+ *size = fill_textconv(textconv, df, &blob);
+ free_filespec(df);
+ } else {
+ blob = read_sha1_file(sha1, &type, size);
+ if (type != OBJ_BLOB)
+ die("object '%s' is not a blob!", sha1_to_hex(sha1));
+ }
+ return blob;
+}
+
+static void append_lost(struct sline *sline, int n, const char *line, int len)
+{
+ struct lline *lline;
+ unsigned long this_mask = (1UL<<n);
+ if (line[len-1] == '\n')
+ len--;
+
+ lline = xmalloc(sizeof(*lline) + len + 1);
+ lline->len = len;
+ lline->next = NULL;
+ lline->prev = sline->plost.lost_tail;
+ if (lline->prev)
+ lline->prev->next = lline;
+ else
+ sline->plost.lost_head = lline;
+ sline->plost.lost_tail = lline;
+ sline->plost.len++;
+ lline->parent_map = this_mask;
+ memcpy(lline->line, line, len);
+ lline->line[len] = 0;
+}
+
+struct combine_diff_state {
+ unsigned int lno;
+ int ob, on, nb, nn;
+ unsigned long nmask;
+ int num_parent;
+ int n;
+ struct sline *sline;
+ struct sline *lost_bucket;
+};
+
+static void consume_line(void *state_, char *line, unsigned long len)
+{
+ struct combine_diff_state *state = state_;
+ if (5 < len && !memcmp("@@ -", line, 4)) {
+ if (parse_hunk_header(line, len,
+ &state->ob, &state->on,
+ &state->nb, &state->nn))
+ return;
+ state->lno = state->nb;
+ if (state->nn == 0) {
+ /* @@ -X,Y +N,0 @@ removed Y lines
+ * that would have come *after* line N
+ * in the result. Our lost buckets hang
+ * to the line after the removed lines,
+ *
+ * Note that this is correct even when N == 0,
+ * in which case the hunk removes the first
+ * line in the file.
+ */
+ state->lost_bucket = &state->sline[state->nb];
+ if (!state->nb)
+ state->nb = 1;
+ } else {
+ state->lost_bucket = &state->sline[state->nb-1];
+ }
+ if (!state->sline[state->nb-1].p_lno)
+ state->sline[state->nb-1].p_lno =
+ xcalloc(state->num_parent,
+ sizeof(unsigned long));
+ state->sline[state->nb-1].p_lno[state->n] = state->ob;
+ return;
+ }
+ if (!state->lost_bucket)
+ return; /* not in any hunk yet */
+ switch (line[0]) {
+ case '-':
+ append_lost(state->lost_bucket, state->n, line+1, len-1);
+ break;
+ case '+':
+ state->sline[state->lno-1].flag |= state->nmask;
+ state->lno++;
+ break;
+ }
+}
+
+static void combine_diff(const unsigned char *parent, unsigned int mode,
+ mmfile_t *result_file,
+ struct sline *sline, unsigned int cnt, int n,
+ int num_parent, int result_deleted,
+ struct userdiff_driver *textconv,
+ const char *path, long flags)
+{
+ unsigned int p_lno, lno;
+ unsigned long nmask = (1UL << n);
+ xpparam_t xpp;
+ xdemitconf_t xecfg;
+ mmfile_t parent_file;
+ struct combine_diff_state state;
+ unsigned long sz;
+
+ if (result_deleted)
+ return; /* result deleted */
+
+ parent_file.ptr = grab_blob(parent, mode, &sz, textconv, path);
+ parent_file.size = sz;
+ memset(&xpp, 0, sizeof(xpp));
+ xpp.flags = flags;
+ memset(&xecfg, 0, sizeof(xecfg));
+ memset(&state, 0, sizeof(state));
+ state.nmask = nmask;
+ state.sline = sline;
+ state.lno = 1;
+ state.num_parent = num_parent;
+ state.n = n;
+
+ xdi_diff_outf(&parent_file, result_file, consume_line, &state,
+ &xpp, &xecfg);
+ free(parent_file.ptr);
+
+ /* Assign line numbers for this parent.
+ *
+ * sline[lno].p_lno[n] records the first line number
+ * (counting from 1) for parent N if the final hunk display
+ * started by showing sline[lno] (possibly showing the lost
+ * lines attached to it first).
+ */
+ for (lno = 0, p_lno = 1; lno <= cnt; lno++) {
+ struct lline *ll;
+ sline[lno].p_lno[n] = p_lno;
+
+ /* Coalesce new lines */
+ if (sline[lno].plost.lost_head) {
+ struct sline *sl = &sline[lno];
+ sl->lost = coalesce_lines(sl->lost, &sl->lenlost,
+ sl->plost.lost_head,
+ sl->plost.len, n, flags);
+ sl->plost.lost_head = sl->plost.lost_tail = NULL;
+ sl->plost.len = 0;
+ }
+
+ /* How many lines would this sline advance the p_lno? */
+ ll = sline[lno].lost;
+ while (ll) {
+ if (ll->parent_map & nmask)
+ p_lno++; /* '-' means parent had it */
+ ll = ll->next;
+ }
+ if (lno < cnt && !(sline[lno].flag & nmask))
+ p_lno++; /* no '+' means parent had it */
+ }
+ sline[lno].p_lno[n] = p_lno; /* trailer */
+}
+
+static unsigned long context = 3;
+static char combine_marker = '@';
+
+static int interesting(struct sline *sline, unsigned long all_mask)
+{
+ /* If some parents lost lines here, or if we have added to
+ * some parent, it is interesting.
+ */
+ return ((sline->flag & all_mask) || sline->lost);
+}
+
+static unsigned long adjust_hunk_tail(struct sline *sline,
+ unsigned long all_mask,
+ unsigned long hunk_begin,
+ unsigned long i)
+{
+ /* i points at the first uninteresting line. If the last line
+ * of the hunk was interesting only because it has some
+ * deletion, then it is not all that interesting for the
+ * purpose of giving trailing context lines. This is because
+ * we output '-' line and then unmodified sline[i-1] itself in
+ * that case which gives us one extra context line.
+ */
+ if ((hunk_begin + 1 <= i) && !(sline[i-1].flag & all_mask))
+ i--;
+ return i;
+}
+
+static unsigned long find_next(struct sline *sline,
+ unsigned long mark,
+ unsigned long i,
+ unsigned long cnt,
+ int look_for_uninteresting)
+{
+ /* We have examined up to i-1 and are about to look at i.
+ * Find next interesting or uninteresting line. Here,
+ * "interesting" does not mean interesting(), but marked by
+ * the give_context() function below (i.e. it includes context
+ * lines that are not interesting to interesting() function
+ * that are surrounded by interesting() ones.
+ */
+ while (i <= cnt)
+ if (look_for_uninteresting
+ ? !(sline[i].flag & mark)
+ : (sline[i].flag & mark))
+ return i;
+ else
+ i++;
+ return i;
+}
+
+static int give_context(struct sline *sline, unsigned long cnt, int num_parent)
+{
+ unsigned long all_mask = (1UL<<num_parent) - 1;
+ unsigned long mark = (1UL<<num_parent);
+ unsigned long no_pre_delete = (2UL<<num_parent);
+ unsigned long i;
+
+ /* Two groups of interesting lines may have a short gap of
+ * uninteresting lines. Connect such groups to give them a
+ * bit of context.
+ *
+ * We first start from what the interesting() function says,
+ * and mark them with "mark", and paint context lines with the
+ * mark. So interesting() would still say false for such context
+ * lines but they are treated as "interesting" in the end.
+ */
+ i = find_next(sline, mark, 0, cnt, 0);
+ if (cnt < i)
+ return 0;
+
+ while (i <= cnt) {
+ unsigned long j = (context < i) ? (i - context) : 0;
+ unsigned long k;
+
+ /* Paint a few lines before the first interesting line. */
+ while (j < i) {
+ if (!(sline[j].flag & mark))
+ sline[j].flag |= no_pre_delete;
+ sline[j++].flag |= mark;
+ }
+
+ again:
+ /* we know up to i is to be included. where does the
+ * next uninteresting one start?
+ */
+ j = find_next(sline, mark, i, cnt, 1);
+ if (cnt < j)
+ break; /* the rest are all interesting */
+
+ /* lookahead context lines */
+ k = find_next(sline, mark, j, cnt, 0);
+ j = adjust_hunk_tail(sline, all_mask, i, j);
+
+ if (k < j + context) {
+ /* k is interesting and [j,k) are not, but
+ * paint them interesting because the gap is small.
+ */
+ while (j < k)
+ sline[j++].flag |= mark;
+ i = k;
+ goto again;
+ }
+
+ /* j is the first uninteresting line and there is
+ * no overlap beyond it within context lines. Paint
+ * the trailing edge a bit.
+ */
+ i = k;
+ k = (j + context < cnt+1) ? j + context : cnt+1;
+ while (j < k)
+ sline[j++].flag |= mark;
+ }
+ return 1;
+}
+
+static int make_hunks(struct sline *sline, unsigned long cnt,
+ int num_parent, int dense)
+{
+ unsigned long all_mask = (1UL<<num_parent) - 1;
+ unsigned long mark = (1UL<<num_parent);
+ unsigned long i;
+ int has_interesting = 0;
+
+ for (i = 0; i <= cnt; i++) {
+ if (interesting(&sline[i], all_mask))
+ sline[i].flag |= mark;
+ else
+ sline[i].flag &= ~mark;
+ }
+ if (!dense)
+ return give_context(sline, cnt, num_parent);
+
+ /* Look at each hunk, and if we have changes from only one
+ * parent, or the changes are the same from all but one
+ * parent, mark that uninteresting.
+ */
+ i = 0;
+ while (i <= cnt) {
+ unsigned long j, hunk_begin, hunk_end;
+ unsigned long same_diff;
+ while (i <= cnt && !(sline[i].flag & mark))
+ i++;
+ if (cnt < i)
+ break; /* No more interesting hunks */
+ hunk_begin = i;
+ for (j = i + 1; j <= cnt; j++) {
+ if (!(sline[j].flag & mark)) {
+ /* Look beyond the end to see if there
+ * is an interesting line after this
+ * hunk within context span.
+ */
+ unsigned long la; /* lookahead */
+ int contin = 0;
+ la = adjust_hunk_tail(sline, all_mask,
+ hunk_begin, j);
+ la = (la + context < cnt + 1) ?
+ (la + context) : cnt + 1;
+ while (la && j <= --la) {
+ if (sline[la].flag & mark) {
+ contin = 1;
+ break;
+ }
+ }
+ if (!contin)
+ break;
+ j = la;
+ }
+ }
+ hunk_end = j;
+
+ /* [i..hunk_end) are interesting. Now is it really
+ * interesting? We check if there are only two versions
+ * and the result matches one of them. That is, we look
+ * at:
+ * (+) line, which records lines added to which parents;
+ * this line appears in the result.
+ * (-) line, which records from what parents the line
+ * was removed; this line does not appear in the result.
+ * then check the set of parents the result has difference
+ * from, from all lines. If there are lines that has
+ * different set of parents that the result has differences
+ * from, that means we have more than two versions.
+ *
+ * Even when we have only two versions, if the result does
+ * not match any of the parents, the it should be considered
+ * interesting. In such a case, we would have all '+' line.
+ * After passing the above "two versions" test, that would
+ * appear as "the same set of parents" to be "all parents".
+ */
+ same_diff = 0;
+ has_interesting = 0;
+ for (j = i; j < hunk_end && !has_interesting; j++) {
+ unsigned long this_diff = sline[j].flag & all_mask;
+ struct lline *ll = sline[j].lost;
+ if (this_diff) {
+ /* This has some changes. Is it the
+ * same as others?
+ */
+ if (!same_diff)
+ same_diff = this_diff;
+ else if (same_diff != this_diff) {
+ has_interesting = 1;
+ break;
+ }
+ }
+ while (ll && !has_interesting) {
+ /* Lost this line from these parents;
+ * who are they? Are they the same?
+ */
+ this_diff = ll->parent_map;
+ if (!same_diff)
+ same_diff = this_diff;
+ else if (same_diff != this_diff) {
+ has_interesting = 1;
+ }
+ ll = ll->next;
+ }
+ }
+
+ if (!has_interesting && same_diff != all_mask) {
+ /* This hunk is not that interesting after all */
+ for (j = hunk_begin; j < hunk_end; j++)
+ sline[j].flag &= ~mark;
+ }
+ i = hunk_end;
+ }
+
+ has_interesting = give_context(sline, cnt, num_parent);
+ return has_interesting;
+}
+
+static void show_parent_lno(struct sline *sline, unsigned long l0, unsigned long l1, int n, unsigned long null_context)
+{
+ l0 = sline[l0].p_lno[n];
+ l1 = sline[l1].p_lno[n];
+ printf(" -%lu,%lu", l0, l1-l0-null_context);
+}
+
+static int hunk_comment_line(const char *bol)
+{
+ int ch;
+
+ if (!bol)
+ return 0;
+ ch = *bol & 0xff;
+ return (isalpha(ch) || ch == '_' || ch == '$');
+}
+
+static void show_line_to_eol(const char *line, int len, const char *reset)
+{
+ int saw_cr_at_eol = 0;
+ if (len < 0)
+ len = strlen(line);
+ saw_cr_at_eol = (len && line[len-1] == '\r');
+
+ printf("%.*s%s%s\n", len - saw_cr_at_eol, line,
+ reset,
+ saw_cr_at_eol ? "\r" : "");
+}
+
+static void dump_sline(struct sline *sline, const char *line_prefix,
+ unsigned long cnt, int num_parent,
+ int use_color, int result_deleted)
+{
+ unsigned long mark = (1UL<<num_parent);
+ unsigned long no_pre_delete = (2UL<<num_parent);
+ int i;
+ unsigned long lno = 0;
+ const char *c_frag = diff_get_color(use_color, DIFF_FRAGINFO);
+ const char *c_func = diff_get_color(use_color, DIFF_FUNCINFO);
+ const char *c_new = diff_get_color(use_color, DIFF_FILE_NEW);
+ const char *c_old = diff_get_color(use_color, DIFF_FILE_OLD);
+ const char *c_plain = diff_get_color(use_color, DIFF_PLAIN);
+ const char *c_reset = diff_get_color(use_color, DIFF_RESET);
+
+ if (result_deleted)
+ return; /* result deleted */
+
+ while (1) {
+ unsigned long hunk_end;
+ unsigned long rlines;
+ const char *hunk_comment = NULL;
+ unsigned long null_context = 0;
+
+ while (lno <= cnt && !(sline[lno].flag & mark)) {
+ if (hunk_comment_line(sline[lno].bol))
+ hunk_comment = sline[lno].bol;
+ lno++;
+ }
+ if (cnt < lno)
+ break;
+ else {
+ for (hunk_end = lno + 1; hunk_end <= cnt; hunk_end++)
+ if (!(sline[hunk_end].flag & mark))
+ break;
+ }
+ rlines = hunk_end - lno;
+ if (cnt < hunk_end)
+ rlines--; /* pointing at the last delete hunk */
+
+ if (!context) {
+ /*
+ * Even when running with --unified=0, all
+ * lines in the hunk needs to be processed in
+ * the loop below in order to show the
+ * deletion recorded in lost_head. However,
+ * we do not want to show the resulting line
+ * with all blank context markers in such a
+ * case. Compensate.
+ */
+ unsigned long j;
+ for (j = lno; j < hunk_end; j++)
+ if (!(sline[j].flag & (mark-1)))
+ null_context++;
+ rlines -= null_context;
+ }
+
+ printf("%s%s", line_prefix, c_frag);
+ for (i = 0; i <= num_parent; i++) putchar(combine_marker);
+ for (i = 0; i < num_parent; i++)
+ show_parent_lno(sline, lno, hunk_end, i, null_context);
+ printf(" +%lu,%lu ", lno+1, rlines);
+ for (i = 0; i <= num_parent; i++) putchar(combine_marker);
+
+ if (hunk_comment) {
+ int comment_end = 0;
+ for (i = 0; i < 40; i++) {
+ int ch = hunk_comment[i] & 0xff;
+ if (!ch || ch == '\n')
+ break;
+ if (!isspace(ch))
+ comment_end = i;
+ }
+ if (comment_end)
+ printf("%s%s %s%s", c_reset,
+ c_plain, c_reset,
+ c_func);
+ for (i = 0; i < comment_end; i++)
+ putchar(hunk_comment[i]);
+ }
+
+ printf("%s\n", c_reset);
+ while (lno < hunk_end) {
+ struct lline *ll;
+ int j;
+ unsigned long p_mask;
+ struct sline *sl = &sline[lno++];
+ ll = (sl->flag & no_pre_delete) ? NULL : sl->lost;
+ while (ll) {
+ printf("%s%s", line_prefix, c_old);
+ for (j = 0; j < num_parent; j++) {
+ if (ll->parent_map & (1UL<<j))
+ putchar('-');
+ else
+ putchar(' ');
+ }
+ show_line_to_eol(ll->line, -1, c_reset);
+ ll = ll->next;
+ }
+ if (cnt < lno)
+ break;
+ p_mask = 1;
+ fputs(line_prefix, stdout);
+ if (!(sl->flag & (mark-1))) {
+ /*
+ * This sline was here to hang the
+ * lost lines in front of it.
+ */
+ if (!context)
+ continue;
+ fputs(c_plain, stdout);
+ }
+ else
+ fputs(c_new, stdout);
+ for (j = 0; j < num_parent; j++) {
+ if (p_mask & sl->flag)
+ putchar('+');
+ else
+ putchar(' ');
+ p_mask <<= 1;
+ }
+ show_line_to_eol(sl->bol, sl->len, c_reset);
+ }
+ }
+}
+
+static void reuse_combine_diff(struct sline *sline, unsigned long cnt,
+ int i, int j)
+{
+ /* We have already examined parent j and we know parent i
+ * and parent j are the same, so reuse the combined result
+ * of parent j for parent i.
+ */
+ unsigned long lno, imask, jmask;
+ imask = (1UL<<i);
+ jmask = (1UL<<j);
+
+ for (lno = 0; lno <= cnt; lno++) {
+ struct lline *ll = sline->lost;
+ sline->p_lno[i] = sline->p_lno[j];
+ while (ll) {
+ if (ll->parent_map & jmask)
+ ll->parent_map |= imask;
+ ll = ll->next;
+ }
+ if (sline->flag & jmask)
+ sline->flag |= imask;
+ sline++;
+ }
+ /* the overall size of the file (sline[cnt]) */
+ sline->p_lno[i] = sline->p_lno[j];
+}
+
+static void dump_quoted_path(const char *head,
+ const char *prefix,
+ const char *path,
+ const char *line_prefix,
+ const char *c_meta, const char *c_reset)
+{
+ static struct strbuf buf = STRBUF_INIT;
+
+ strbuf_reset(&buf);
+ strbuf_addstr(&buf, line_prefix);
+ strbuf_addstr(&buf, c_meta);
+ strbuf_addstr(&buf, head);
+ quote_two_c_style(&buf, prefix, path, 0);
+ strbuf_addstr(&buf, c_reset);
+ puts(buf.buf);
+}
+
+static void show_combined_header(struct combine_diff_path *elem,
+ int num_parent,
+ int dense,
+ struct rev_info *rev,
+ const char *line_prefix,
+ int mode_differs,
+ int show_file_header)
+{
+ struct diff_options *opt = &rev->diffopt;
+ int abbrev = DIFF_OPT_TST(opt, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
+ const char *a_prefix = opt->a_prefix ? opt->a_prefix : "a/";
+ const char *b_prefix = opt->b_prefix ? opt->b_prefix : "b/";
+ const char *c_meta = diff_get_color_opt(opt, DIFF_METAINFO);
+ const char *c_reset = diff_get_color_opt(opt, DIFF_RESET);
+ const char *abb;
+ int added = 0;
+ int deleted = 0;
+ int i;
+
+ if (rev->loginfo && !rev->no_commit_id)
+ show_log(rev);
+
+ dump_quoted_path(dense ? "diff --cc " : "diff --combined ",
+ "", elem->path, line_prefix, c_meta, c_reset);
+ printf("%s%sindex ", line_prefix, c_meta);
+ for (i = 0; i < num_parent; i++) {
+ abb = find_unique_abbrev(elem->parent[i].sha1,
+ abbrev);
+ printf("%s%s", i ? "," : "", abb);
+ }
+ abb = find_unique_abbrev(elem->sha1, abbrev);
+ printf("..%s%s\n", abb, c_reset);
+
+ if (mode_differs) {
+ deleted = !elem->mode;
+
+ /* We say it was added if nobody had it */
+ added = !deleted;
+ for (i = 0; added && i < num_parent; i++)
+ if (elem->parent[i].status !=
+ DIFF_STATUS_ADDED)
+ added = 0;
+ if (added)
+ printf("%s%snew file mode %06o",
+ line_prefix, c_meta, elem->mode);
+ else {
+ if (deleted)
+ printf("%s%sdeleted file ",
+ line_prefix, c_meta);
+ printf("mode ");
+ for (i = 0; i < num_parent; i++) {
+ printf("%s%06o", i ? "," : "",
+ elem->parent[i].mode);
+ }
+ if (elem->mode)
+ printf("..%06o", elem->mode);
+ }
+ printf("%s\n", c_reset);
+ }
+
+ if (!show_file_header)
+ return;
+
+ if (added)
+ dump_quoted_path("--- ", "", "/dev/null",
+ line_prefix, c_meta, c_reset);
+ else
+ dump_quoted_path("--- ", a_prefix, elem->path,
+ line_prefix, c_meta, c_reset);
+ if (deleted)
+ dump_quoted_path("+++ ", "", "/dev/null",
+ line_prefix, c_meta, c_reset);
+ else
+ dump_quoted_path("+++ ", b_prefix, elem->path,
+ line_prefix, c_meta, c_reset);
+}
+
+static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
+ int dense, int working_tree_file,
+ struct rev_info *rev)
+{
+ struct diff_options *opt = &rev->diffopt;
+ unsigned long result_size, cnt, lno;
+ int result_deleted = 0;
+ char *result, *cp;
+ struct sline *sline; /* survived lines */
+ int mode_differs = 0;
+ int i, show_hunks;
+ mmfile_t result_file;
+ struct userdiff_driver *userdiff;
+ struct userdiff_driver *textconv = NULL;
+ int is_binary;
+ const char *line_prefix = diff_line_prefix(opt);
+
+ context = opt->context;
+ userdiff = userdiff_find_by_path(elem->path);
+ if (!userdiff)
+ userdiff = userdiff_find_by_name("default");
+ if (DIFF_OPT_TST(opt, ALLOW_TEXTCONV))
+ textconv = userdiff_get_textconv(userdiff);
+
+ /* Read the result of merge first */
+ if (!working_tree_file)
+ result = grab_blob(elem->sha1, elem->mode, &result_size,
+ textconv, elem->path);
+ else {
+ /* Used by diff-tree to read from the working tree */
+ struct stat st;
+ int fd = -1;
+
+ if (lstat(elem->path, &st) < 0)
+ goto deleted_file;
+
+ if (S_ISLNK(st.st_mode)) {
+ struct strbuf buf = STRBUF_INIT;
+
+ if (strbuf_readlink(&buf, elem->path, st.st_size) < 0) {
+ error("readlink(%s): %s", elem->path,
+ strerror(errno));
+ return;
+ }
+ result_size = buf.len;
+ result = strbuf_detach(&buf, NULL);
+ elem->mode = canon_mode(st.st_mode);
+ } else if (S_ISDIR(st.st_mode)) {
+ unsigned char sha1[20];
+ if (resolve_gitlink_ref(elem->path, "HEAD", sha1) < 0)
+ result = grab_blob(elem->sha1, elem->mode,
+ &result_size, NULL, NULL);
+ else
+ result = grab_blob(sha1, elem->mode,
+ &result_size, NULL, NULL);
+ } else if (textconv) {
+ struct diff_filespec *df = alloc_filespec(elem->path);
+ fill_filespec(df, null_sha1, 0, st.st_mode);
+ result_size = fill_textconv(textconv, df, &result);
+ free_filespec(df);
+ } else if (0 <= (fd = open(elem->path, O_RDONLY))) {
+ size_t len = xsize_t(st.st_size);
+ ssize_t done;
+ int is_file, i;
+
+ elem->mode = canon_mode(st.st_mode);
+ /* if symlinks don't work, assume symlink if all parents
+ * are symlinks
+ */
+ is_file = has_symlinks;
+ for (i = 0; !is_file && i < num_parent; i++)
+ is_file = !S_ISLNK(elem->parent[i].mode);
+ if (!is_file)
+ elem->mode = canon_mode(S_IFLNK);
+
+ result_size = len;
+ result = xmalloc(len + 1);
+
+ done = read_in_full(fd, result, len);
+ if (done < 0)
+ die_errno("read error '%s'", elem->path);
+ else if (done < len)
+ die("early EOF '%s'", elem->path);
+
+ result[len] = 0;
+
+ /* If not a fake symlink, apply filters, e.g. autocrlf */
+ if (is_file) {
+ struct strbuf buf = STRBUF_INIT;
+
+ if (convert_to_git(elem->path, result, len, &buf, safe_crlf)) {
+ free(result);
+ result = strbuf_detach(&buf, &len);
+ result_size = len;
+ }
+ }
+ }
+ else {
+ deleted_file:
+ result_deleted = 1;
+ result_size = 0;
+ elem->mode = 0;
+ result = xcalloc(1, 1);
+ }
+
+ if (0 <= fd)
+ close(fd);
+ }
+
+ for (i = 0; i < num_parent; i++) {
+ if (elem->parent[i].mode != elem->mode) {
+ mode_differs = 1;
+ break;
+ }
+ }
+
+ if (textconv)
+ is_binary = 0;
+ else if (userdiff->binary != -1)
+ is_binary = userdiff->binary;
+ else {
+ is_binary = buffer_is_binary(result, result_size);
+ for (i = 0; !is_binary && i < num_parent; i++) {
+ char *buf;
+ unsigned long size;
+ buf = grab_blob(elem->parent[i].sha1,
+ elem->parent[i].mode,
+ &size, NULL, NULL);
+ if (buffer_is_binary(buf, size))
+ is_binary = 1;
+ free(buf);
+ }
+ }
+ if (is_binary) {
+ show_combined_header(elem, num_parent, dense, rev,
+ line_prefix, mode_differs, 0);
+ printf("Binary files differ\n");
+ free(result);
+ return;
+ }
+
+ for (cnt = 0, cp = result; cp < result + result_size; cp++) {
+ if (*cp == '\n')
+ cnt++;
+ }
+ if (result_size && result[result_size-1] != '\n')
+ cnt++; /* incomplete line */
+
+ sline = xcalloc(cnt+2, sizeof(*sline));
+ sline[0].bol = result;
+ for (lno = 0, cp = result; cp < result + result_size; cp++) {
+ if (*cp == '\n') {
+ sline[lno].len = cp - sline[lno].bol;
+ lno++;
+ if (lno < cnt)
+ sline[lno].bol = cp + 1;
+ }
+ }
+ if (result_size && result[result_size-1] != '\n')
+ sline[cnt-1].len = result_size - (sline[cnt-1].bol - result);
+
+ result_file.ptr = result;
+ result_file.size = result_size;
+
+ /* Even p_lno[cnt+1] is valid -- that is for the end line number
+ * for deletion hunk at the end.
+ */
+ sline[0].p_lno = xcalloc((cnt+2) * num_parent, sizeof(unsigned long));
+ for (lno = 0; lno <= cnt; lno++)
+ sline[lno+1].p_lno = sline[lno].p_lno + num_parent;
+
+ for (i = 0; i < num_parent; i++) {
+ int j;
+ for (j = 0; j < i; j++) {
+ if (!hashcmp(elem->parent[i].sha1,
+ elem->parent[j].sha1)) {
+ reuse_combine_diff(sline, cnt, i, j);
+ break;
+ }
+ }
+ if (i <= j)
+ combine_diff(elem->parent[i].sha1,
+ elem->parent[i].mode,
+ &result_file, sline,
+ cnt, i, num_parent, result_deleted,
+ textconv, elem->path, opt->xdl_opts);
+ }
+
+ show_hunks = make_hunks(sline, cnt, num_parent, dense);
+
+ if (show_hunks || mode_differs || working_tree_file) {
+ show_combined_header(elem, num_parent, dense, rev,
+ line_prefix, mode_differs, 1);
+ dump_sline(sline, line_prefix, cnt, num_parent,
+ opt->use_color, result_deleted);
+ }
+ free(result);
+
+ for (lno = 0; lno < cnt; lno++) {
+ if (sline[lno].lost) {
+ struct lline *ll = sline[lno].lost;
+ while (ll) {
+ struct lline *tmp = ll;
+ ll = ll->next;
+ free(tmp);
+ }
+ }
+ }
+ free(sline[0].p_lno);
+ free(sline);
+}
+
+static void show_raw_diff(struct combine_diff_path *p, int num_parent, struct rev_info *rev)
+{
+ struct diff_options *opt = &rev->diffopt;
+ int line_termination, inter_name_termination, i;
+ const char *line_prefix = diff_line_prefix(opt);
+
+ line_termination = opt->line_termination;
+ inter_name_termination = '\t';
+ if (!line_termination)
+ inter_name_termination = 0;
+
+ if (rev->loginfo && !rev->no_commit_id)
+ show_log(rev);
+
+
+ if (opt->output_format & DIFF_FORMAT_RAW) {
+ printf("%s", line_prefix);
+
+ /* As many colons as there are parents */
+ for (i = 0; i < num_parent; i++)
+ putchar(':');
+
+ /* Show the modes */
+ for (i = 0; i < num_parent; i++)
+ printf("%06o ", p->parent[i].mode);
+ printf("%06o", p->mode);
+
+ /* Show sha1's */
+ for (i = 0; i < num_parent; i++)
+ printf(" %s", diff_unique_abbrev(p->parent[i].sha1,
+ opt->abbrev));
+ printf(" %s ", diff_unique_abbrev(p->sha1, opt->abbrev));
+ }
+
+ if (opt->output_format & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS)) {
+ for (i = 0; i < num_parent; i++)
+ putchar(p->parent[i].status);
+ putchar(inter_name_termination);
+ }
+
+ write_name_quoted(p->path, stdout, line_termination);
+}
+
+/*
+ * The result (p->elem) is from the working tree and their
+ * parents are typically from multiple stages during a merge
+ * (i.e. diff-files) or the state in HEAD and in the index
+ * (i.e. diff-index).
+ */
+void show_combined_diff(struct combine_diff_path *p,
+ int num_parent,
+ int dense,
+ struct rev_info *rev)
+{
+ struct diff_options *opt = &rev->diffopt;
+
+ if (!p->len)
+ return;
+ if (opt->output_format & (DIFF_FORMAT_RAW |
+ DIFF_FORMAT_NAME |
+ DIFF_FORMAT_NAME_STATUS))
+ show_raw_diff(p, num_parent, rev);
+ else if (opt->output_format & DIFF_FORMAT_PATCH)
+ show_patch_diff(p, num_parent, dense, 1, rev);
+}
+
+static void free_combined_pair(struct diff_filepair *pair)
+{
+ free(pair->two);
+ free(pair);
+}
+
+/*
+ * A combine_diff_path expresses N parents on the LHS against 1 merge
+ * result. Synthesize a diff_filepair that has N entries on the "one"
+ * side and 1 entry on the "two" side.
+ *
+ * In the future, we might want to add more data to combine_diff_path
+ * so that we can fill fields we are ignoring (most notably, size) here,
+ * but currently nobody uses it, so this should suffice for now.
+ */
+static struct diff_filepair *combined_pair(struct combine_diff_path *p,
+ int num_parent)
+{
+ int i;
+ struct diff_filepair *pair;
+ struct diff_filespec *pool;
+
+ pair = xmalloc(sizeof(*pair));
+ pool = xcalloc(num_parent + 1, sizeof(struct diff_filespec));
+ pair->one = pool + 1;
+ pair->two = pool;
+
+ for (i = 0; i < num_parent; i++) {
+ pair->one[i].path = p->path;
+ pair->one[i].mode = p->parent[i].mode;
+ hashcpy(pair->one[i].sha1, p->parent[i].sha1);
+ pair->one[i].sha1_valid = !is_null_sha1(p->parent[i].sha1);
+ pair->one[i].has_more_entries = 1;
+ }
+ pair->one[num_parent - 1].has_more_entries = 0;
+
+ pair->two->path = p->path;
+ pair->two->mode = p->mode;
+ hashcpy(pair->two->sha1, p->sha1);
+ pair->two->sha1_valid = !is_null_sha1(p->sha1);
+ return pair;
+}
+
+static void handle_combined_callback(struct diff_options *opt,
+ struct combine_diff_path *paths,
+ int num_parent,
+ int num_paths)
+{
+ struct combine_diff_path *p;
+ struct diff_queue_struct q;
+ int i;
+
+ q.queue = xcalloc(num_paths, sizeof(struct diff_filepair *));
+ q.alloc = num_paths;
+ q.nr = num_paths;
+ for (i = 0, p = paths; p; p = p->next) {
+ if (!p->len)
+ continue;
+ q.queue[i++] = combined_pair(p, num_parent);
+ }
+ opt->format_callback(&q, opt, opt->format_callback_data);
+ for (i = 0; i < num_paths; i++)
+ free_combined_pair(q.queue[i]);
+ free(q.queue);
+}
+
+void diff_tree_combined(const unsigned char *sha1,
+ const struct sha1_array *parents,
+ int dense,
+ struct rev_info *rev)
+{
+ struct diff_options *opt = &rev->diffopt;
+ struct diff_options diffopts;
+ struct combine_diff_path *p, *paths = NULL;
+ int i, num_paths, needsep, show_log_first, num_parent = parents->nr;
+
+ diffopts = *opt;
+ diff_tree_setup_paths(diffopts.pathspec.raw, &diffopts);
+ diffopts.output_format = DIFF_FORMAT_NO_OUTPUT;
+ DIFF_OPT_SET(&diffopts, RECURSIVE);
+ DIFF_OPT_CLR(&diffopts, ALLOW_EXTERNAL);
+
+ show_log_first = !!rev->loginfo && !rev->no_commit_id;
+ needsep = 0;
+ /* find set of paths that everybody touches */
+ for (i = 0; i < num_parent; i++) {
+ /* show stat against the first parent even
+ * when doing combined diff.
+ */
+ int stat_opt = (opt->output_format &
+ (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT));
+ if (i == 0 && stat_opt)
+ diffopts.output_format = stat_opt;
+ else
+ diffopts.output_format = DIFF_FORMAT_NO_OUTPUT;
+ diff_tree_sha1(parents->sha1[i], sha1, "", &diffopts);
+ diffcore_std(&diffopts);
+ paths = intersect_paths(paths, i, num_parent);
+
+ if (show_log_first && i == 0) {
+ show_log(rev);
+
+ if (rev->verbose_header && opt->output_format)
+ printf("%s%c", diff_line_prefix(opt),
+ opt->line_termination);
+ }
+ diff_flush(&diffopts);
+ }
+
+ /* find out surviving paths */
+ for (num_paths = 0, p = paths; p; p = p->next) {
+ if (p->len)
+ num_paths++;
+ }
+ if (num_paths) {
+ if (opt->output_format & (DIFF_FORMAT_RAW |
+ DIFF_FORMAT_NAME |
+ DIFF_FORMAT_NAME_STATUS)) {
+ for (p = paths; p; p = p->next) {
+ if (p->len)
+ show_raw_diff(p, num_parent, rev);
+ }
+ needsep = 1;
+ }
+ else if (opt->output_format &
+ (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT))
+ needsep = 1;
+ else if (opt->output_format & DIFF_FORMAT_CALLBACK)
+ handle_combined_callback(opt, paths, num_parent, num_paths);
+
+ if (opt->output_format & DIFF_FORMAT_PATCH) {
+ if (needsep)
+ printf("%s%c", diff_line_prefix(opt),
+ opt->line_termination);
+ for (p = paths; p; p = p->next) {
+ if (p->len)
+ show_patch_diff(p, num_parent, dense,
+ 0, rev);
+ }
+ }
+ }
+
+ /* Clean things up */
+ while (paths) {
+ struct combine_diff_path *tmp = paths;
+ paths = paths->next;
+ free(tmp);
+ }
+
+ diff_tree_release_paths(&diffopts);
+}
+
+void diff_tree_combined_merge(const struct commit *commit, int dense,
+ struct rev_info *rev)
+{
+ struct commit_list *parent = commit->parents;
+ struct sha1_array parents = SHA1_ARRAY_INIT;
+
+ while (parent) {
+ sha1_array_append(&parents, parent->item->object.sha1);
+ parent = parent->next;
+ }
+ diff_tree_combined(commit->object.sha1, &parents, dense, rev);
+ sha1_array_clear(&parents);
+}