aboutsummaryrefslogtreecommitdiff
path: root/combine-diff.c
diff options
context:
space:
mode:
Diffstat (limited to 'combine-diff.c')
-rw-r--r--combine-diff.c469
1 files changed, 469 insertions, 0 deletions
diff --git a/combine-diff.c b/combine-diff.c
new file mode 100644
index 000000000..669002349
--- /dev/null
+++ b/combine-diff.c
@@ -0,0 +1,469 @@
+#include "cache.h"
+#include "commit.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "quote.h"
+
+struct path_list {
+ struct path_list *next;
+ int len;
+ char *path;
+ unsigned char sha1[20];
+ unsigned char parent_sha1[FLEX_ARRAY][20];
+};
+
+static int uninteresting(struct diff_filepair *p)
+{
+ if (diff_unmodified_pair(p))
+ return 1;
+ if (!S_ISREG(p->one->mode) || !S_ISREG(p->two->mode))
+ return 1;
+ return 0;
+}
+
+static struct path_list *intersect_paths(struct path_list *curr,
+ int n, int num_parent)
+{
+ struct diff_queue_struct *q = &diff_queued_diff;
+ struct path_list *p;
+ int i;
+
+ if (!n) {
+ struct path_list *list = NULL, *tail = NULL;
+ for (i = 0; i < q->nr; i++) {
+ int len;
+ const char *path;
+ if (uninteresting(q->queue[i]))
+ continue;
+ path = q->queue[i]->two->path;
+ len = strlen(path);
+
+ p = xmalloc(sizeof(*p) + len + 1 + num_parent * 20);
+ p->path = (char*) &(p->parent_sha1[num_parent][0]);
+ memcpy(p->path, path, len);
+ p->path[len] = 0;
+ p->len = len;
+ p->next = NULL;
+ memcpy(p->sha1, q->queue[i]->two->sha1, 20);
+ memcpy(p->parent_sha1[n], q->queue[i]->one->sha1, 20);
+ if (!tail)
+ list = tail = p;
+ else {
+ tail->next = p;
+ p = tail;
+ }
+ }
+ 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 (uninteresting(q->queue[i]))
+ continue;
+ path = q->queue[i]->two->path;
+ len = strlen(path);
+ if (len == p->len && !memcmp(path, p->path, len)) {
+ found = 1;
+ memcpy(p->parent_sha1[n],
+ q->queue[i]->one->sha1, 20);
+ break;
+ }
+ }
+ if (!found)
+ p->len = 0;
+ }
+ return curr;
+}
+
+struct lline {
+ struct lline *next;
+ int len;
+ unsigned long parent_map;
+ char line[FLEX_ARRAY];
+};
+
+struct sline {
+ struct lline *lost_head, **lost_tail;
+ char *bol;
+ int len;
+ unsigned long flag;
+};
+
+static char *grab_blob(const unsigned char *sha1, unsigned long *size)
+{
+ char *blob;
+ char type[20];
+ if (!memcmp(sha1, null_sha1, 20)) {
+ /* deleted blob */
+ *size = 0;
+ return xcalloc(1, 1);
+ }
+ blob = read_sha1_file(sha1, type, size);
+ if (strcmp(type, "blob"))
+ die("object '%s' is not a blob!", sha1_to_hex(sha1));
+ return blob;
+}
+
+#define TMPPATHLEN 50
+#define MAXLINELEN 10240
+
+static void write_to_temp_file(char *tmpfile, void *blob, unsigned long size)
+{
+ int fd = git_mkstemp(tmpfile, TMPPATHLEN, ".diff_XXXXXX");
+ if (fd < 0)
+ die("unable to create temp-file");
+ if (write(fd, blob, size) != size)
+ die("unable to write temp-file");
+ close(fd);
+}
+
+static void write_temp_blob(char *tmpfile, const unsigned char *sha1)
+{
+ unsigned long size;
+ void *blob;
+ blob = grab_blob(sha1, &size);
+ write_to_temp_file(tmpfile, blob, size);
+ free(blob);
+}
+
+static int parse_num(char **cp_p, unsigned int *num_p)
+{
+ char *cp = *cp_p;
+ unsigned int num = 0;
+ int read_some;
+
+ while ('0' <= *cp && *cp <= '9')
+ num = num * 10 + *cp++ - '0';
+ if (!(read_some = cp - *cp_p))
+ return -1;
+ *cp_p = cp;
+ *num_p = num;
+ return 0;
+}
+
+static int parse_hunk_header(char *line, int len,
+ unsigned int *ob, unsigned int *on,
+ unsigned int *nb, unsigned int *nn)
+{
+ char *cp;
+ cp = line + 4;
+ if (parse_num(&cp, ob)) {
+ bad_line:
+ return error("malformed diff output: %s", line);
+ }
+ if (*cp == ',') {
+ cp++;
+ if (parse_num(&cp, on))
+ goto bad_line;
+ }
+ else
+ *on = 1;
+ if (*cp++ != ' ' || *cp++ != '+')
+ goto bad_line;
+ if (parse_num(&cp, nb))
+ goto bad_line;
+ if (*cp == ',') {
+ cp++;
+ if (parse_num(&cp, nn))
+ goto bad_line;
+ }
+ else
+ *nn = 1;
+ return -!!memcmp(cp, " @@", 3);
+}
+
+static void append_lost(struct sline *sline, int n, const char *line)
+{
+ struct lline *lline;
+ int len = strlen(line);
+ unsigned long this_mask = (1UL<<n);
+ if (line[len-1] == '\n')
+ len--;
+
+ /* Check to see if we can squash things */
+ if (sline->lost_head) {
+ struct lline *last_one = NULL;
+ /* We cannot squash it with earlier one */
+ for (lline = sline->lost_head;
+ lline;
+ lline = lline->next)
+ if (lline->parent_map & this_mask)
+ last_one = lline;
+ lline = last_one ? last_one->next : sline->lost_head;
+ while (lline) {
+ if (lline->len == len &&
+ !memcmp(lline->line, line, len)) {
+ lline->parent_map |= this_mask;
+ return;
+ }
+ lline = lline->next;
+ }
+ }
+
+ lline = xmalloc(sizeof(*lline) + len + 1);
+ lline->len = len;
+ lline->next = NULL;
+ lline->parent_map = this_mask;
+ memcpy(lline->line, line, len);
+ lline->line[len] = 0;
+ if (sline->lost_head)
+ *(sline->lost_tail) = lline;
+ else
+ sline->lost_head = lline;
+ sline->lost_tail = &lline->next;
+}
+
+static void combine_diff(const unsigned char *parent, const char *ourtmp,
+ struct sline *sline, int cnt, int n)
+{
+ FILE *in;
+ char parent_tmp[TMPPATHLEN];
+ char cmd[TMPPATHLEN * 2 + 1024];
+ char line[MAXLINELEN];
+ unsigned int lno, ob, on, nb, nn;
+ unsigned long pmask = ~(1UL << n);
+ struct sline *lost_bucket = NULL;
+
+ write_temp_blob(parent_tmp, parent);
+ sprintf(cmd, "diff --unified=0 -La/x -Lb/x '%s' '%s'",
+ parent_tmp, ourtmp);
+ in = popen(cmd, "r");
+ if (!in)
+ return;
+
+ lno = 1;
+ while (fgets(line, sizeof(line), in) != NULL) {
+ int len = strlen(line);
+ if (5 < len && !memcmp("@@ -", line, 4)) {
+ if (parse_hunk_header(line, len,
+ &ob, &on, &nb, &nn))
+ break;
+ lno = nb;
+ if (!nb) {
+ /* @@ -1,2 +0,0 @@ to remove the
+ * first two lines...
+ */
+ nb = 1;
+ }
+ lost_bucket = &sline[nb-1]; /* sline is 0 based */
+ continue;
+ }
+ if (!lost_bucket)
+ continue;
+ switch (line[0]) {
+ case '-':
+ append_lost(lost_bucket, n, line+1);
+ break;
+ case '+':
+ sline[lno-1].flag &= pmask;
+ lno++;
+ break;
+ }
+ }
+ fclose(in);
+ unlink(parent_tmp);
+}
+
+static unsigned long context = 3;
+static char combine_marker = '@';
+
+static int interesting(struct sline *sline, unsigned long all_mask)
+{
+ return ((sline->flag & all_mask) != all_mask || sline->lost_head);
+}
+
+static void make_hunks(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 i;
+
+ i = 0;
+ while (i < cnt) {
+ if (interesting(&sline[i], all_mask)) {
+ unsigned long j = (context < i) ? i - context : 0;
+ while (j <= i)
+ sline[j++].flag |= mark;
+ while (++i < cnt) {
+ if (!interesting(&sline[i], all_mask))
+ break;
+ sline[i].flag |= mark;
+ }
+ j = (i + context < cnt) ? i + context : cnt;
+ while (i < j)
+ sline[i++].flag |= mark;
+ continue;
+ }
+ i++;
+ }
+}
+
+static void dump_sline(struct sline *sline, int cnt, int num_parent)
+{
+ unsigned long mark = (1UL<<num_parent);
+ int i;
+ int lno = 0;
+
+ while (1) {
+ struct sline *sl = &sline[lno];
+ int hunk_end;
+ while (lno < cnt && !(sline[lno].flag & mark))
+ lno++;
+ if (cnt <= lno)
+ break;
+ for (hunk_end = lno + 1; hunk_end < cnt; hunk_end++)
+ if (!(sline[hunk_end].flag & mark))
+ break;
+ for (i = 0; i <= num_parent; i++) putchar(combine_marker);
+ printf(" +%d,%d ", lno+1, hunk_end-lno);
+ for (i = 0; i <= num_parent; i++) putchar(combine_marker);
+ putchar('\n');
+ while (lno < hunk_end) {
+ struct lline *ll;
+ int j;
+ sl = &sline[lno++];
+ ll = sl->lost_head;
+ while (ll) {
+ for (j = 0; j < num_parent; j++) {
+ if (ll->parent_map & (1UL<<j))
+ putchar('-');
+ else
+ putchar(' ');
+ }
+ putchar(' ');
+ puts(ll->line);
+ ll = ll->next;
+ }
+ for (j = 0; j < num_parent; j++) {
+ if ((1UL<<j) & sl->flag)
+ putchar(' ');
+ else
+ putchar('+');
+ }
+ printf(" %.*s\n", sl->len, sl->bol);
+ }
+ }
+}
+
+static void show_combined_diff(struct path_list *elem, int num_parent)
+{
+ unsigned long size, cnt, lno;
+ char *result, *cp, *ep;
+ struct sline *sline; /* survived lines */
+ int i;
+ char ourtmp[TMPPATHLEN];
+
+ /* Read the result of merge first */
+ result = grab_blob(elem->sha1, &size);
+ write_to_temp_file(ourtmp, result, size);
+
+ for (cnt = 0, cp = result; cp - result < size; cp++) {
+ if (*cp == '\n')
+ cnt++;
+ }
+ if (result[size-1] != '\n')
+ cnt++; /* incomplete line */
+
+ sline = xcalloc(cnt, sizeof(*sline));
+ ep = result;
+ sline[0].bol = result;
+ for (lno = 0, cp = result; cp - result < size; cp++) {
+ if (*cp == '\n') {
+ sline[lno].len = cp - sline[lno].bol;
+ sline[lno].flag = (1UL<<num_parent) - 1;
+ lno++;
+ if (lno < cnt)
+ sline[lno].bol = cp + 1;
+ }
+ }
+ if (result[size-1] != '\n') {
+ sline[cnt-1].len = size - (sline[cnt-1].bol - result);
+ sline[cnt-1].flag = (1UL<<num_parent) - 1;
+ }
+
+ for (i = 0; i < num_parent; i++)
+ combine_diff(elem->parent_sha1[i], ourtmp, sline, cnt, i);
+
+ make_hunks(sline, cnt, num_parent);
+
+ dump_sline(sline, cnt, num_parent);
+ unlink(ourtmp);
+ free(result);
+
+ for (i = 0; i < cnt; i++) {
+ if (sline[i].lost_head) {
+ struct lline *ll = sline[i].lost_head;
+ while (ll) {
+ struct lline *tmp = ll;
+ ll = ll->next;
+ free(tmp);
+ }
+ }
+ }
+ free(sline);
+}
+
+int diff_tree_combined_merge(const unsigned char *sha1,
+ const char *header, int show_empty_merge)
+{
+ struct commit *commit = lookup_commit(sha1);
+ struct diff_options diffopts;
+ struct commit_list *parents;
+ struct path_list *p, *paths = NULL;
+ int num_parent, i, num_paths;
+
+ diff_setup(&diffopts);
+ diffopts.output_format = DIFF_FORMAT_NO_OUTPUT;
+ diffopts.recursive = 1;
+
+ /* count parents */
+ for (parents = commit->parents, num_parent = 0;
+ parents;
+ parents = parents->next, num_parent++)
+ ; /* nothing */
+
+ /* find set of paths that everybody touches */
+ for (parents = commit->parents, i = 0;
+ parents;
+ parents = parents->next, i++) {
+ struct commit *parent = parents->item;
+ diff_tree_sha1(parent->object.sha1, commit->object.sha1, "",
+ &diffopts);
+ paths = intersect_paths(paths, i, num_parent);
+ 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 || show_empty_merge) {
+ puts(header);
+ for (p = paths; p; p = p->next) {
+ if (!p->len)
+ continue;
+ printf("diff --combined ");
+ if (quote_c_style(p->path, NULL, NULL, 0))
+ quote_c_style(p->path, NULL, stdout, 0);
+ else
+ printf("%s", p->path);
+ putchar('\n');
+ show_combined_diff(p, num_parent);
+ }
+ }
+
+ /* Clean things up */
+ while (paths) {
+ struct path_list *tmp = paths;
+ paths = paths->next;
+ free(tmp);
+ }
+ return 0;
+}
generated by cgit v1.2.1 (git 2.18.0) at 2024-07-31 19:43:33 +0000