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-rw-r--r--ui-ssdiff.c145
1 files changed, 120 insertions, 25 deletions
diff --git a/ui-ssdiff.c b/ui-ssdiff.c
index 5673642..408e620 100644
--- a/ui-ssdiff.c
+++ b/ui-ssdiff.c
@@ -15,6 +15,52 @@ struct deferred_lines {
static struct deferred_lines *deferred_old, *deferred_old_last;
static struct deferred_lines *deferred_new, *deferred_new_last;
+static char *longest_common_subsequence(char *A, char *B)
+{
+ int i, j, ri;
+ int m = strlen(A);
+ int n = strlen(B);
+ int L[m + 1][n + 1];
+ int tmp1, tmp2;
+ int lcs_length;
+ char *result;
+
+ for (i = m; i >= 0; i--) {
+ for (j = n; j >= 0; j--) {
+ if (A[i] == '\0' || B[j] == '\0') {
+ L[i][j] = 0;
+ } else if (A[i] == B[j]) {
+ L[i][j] = 1 + L[i + 1][j + 1];
+ } else {
+ tmp1 = L[i + 1][j];
+ tmp2 = L[i][j + 1];
+ L[i][j] = (tmp1 > tmp2 ? tmp1 : tmp2);
+ }
+ }
+ }
+
+ lcs_length = L[0][0];
+ result = xmalloc(lcs_length + 2);
+ memset(result, 0, sizeof(*result) * (lcs_length + 2));
+
+ ri = 0;
+ i = 0;
+ j = 0;
+ while (i < m && j < n) {
+ if (A[i] == B[j]) {
+ result[ri] = A[i];
+ ri += 1;
+ i += 1;
+ j += 1;
+ } else if (L[i + 1][j] >= L[i][j + 1]) {
+ i += 1;
+ } else {
+ j += 1;
+ }
+ }
+ return result;
+}
+
static int line_from_hunk(char *line, char type)
{
char *buf1, *buf2;
@@ -73,6 +119,17 @@ static char *replace_tabs(char *line)
return result;
}
+static int calc_deferred_lines(struct deferred_lines *start)
+{
+ struct deferred_lines *item = start;
+ int result = 0;
+ while (item) {
+ result += 1;
+ item = item->next;
+ }
+ return result;
+}
+
static void deferred_old_add(char *line, int line_no)
{
struct deferred_lines *item = xmalloc(sizeof(struct deferred_lines));
@@ -101,9 +158,45 @@ static void deferred_new_add(char *line, int line_no)
}
}
-static void print_ssdiff_line(char *class, int old_line_no, char *old_line,
- int new_line_no, char *new_line)
+static void print_part_with_lcs(char *class, char *line, char *lcs)
+{
+ int line_len = strlen(line);
+ int i, j;
+ char c[2] = " ";
+ int same = 1;
+
+ j = 0;
+ for (i = 0; i < line_len; i++) {
+ c[0] = line[i];
+ if (same) {
+ if (line[i] == lcs[j])
+ j += 1;
+ else {
+ same = 0;
+ htmlf("<span class='%s'>", class);
+ }
+ } else if (line[i] == lcs[j]) {
+ same = 1;
+ htmlf("</span>");
+ j += 1;
+ }
+ html_txt(c);
+ }
+}
+
+static void print_ssdiff_line(char *class,
+ int old_line_no,
+ char *old_line,
+ int new_line_no,
+ char *new_line, int individual_chars)
{
+ char *lcs = NULL;
+ if (old_line)
+ old_line = replace_tabs(old_line + 1);
+ if (new_line)
+ new_line = replace_tabs(new_line + 1);
+ if (individual_chars && old_line && new_line)
+ lcs = longest_common_subsequence(old_line, new_line);
html("<tr>");
if (old_line_no > 0)
htmlf("<td class='lineno'>%d</td><td class='%s'>",
@@ -112,15 +205,14 @@ static void print_ssdiff_line(char *class, int old_line_no, char *old_line,
htmlf("<td class='lineno'></td><td class='%s'>", class);
else
htmlf("<td class='lineno'></td><td class='%s_dark'>", class);
-
if (old_line) {
- old_line = replace_tabs(old_line + 1);
- html_txt(old_line);
- free(old_line);
+ if (lcs)
+ print_part_with_lcs("del", old_line, lcs);
+ else
+ html_txt(old_line);
}
html("</td>");
-
if (new_line_no > 0)
htmlf("<td class='lineno'>%d</td><td class='%s'>",
new_line_no, class);
@@ -128,24 +220,29 @@ static void print_ssdiff_line(char *class, int old_line_no, char *old_line,
htmlf("<td class='lineno'></td><td class='%s'>", class);
else
htmlf("<td class='lineno'></td><td class='%s_dark'>", class);
-
if (new_line) {
- new_line = replace_tabs(new_line + 1);
- html_txt(new_line);
- free(new_line);
+ if (lcs)
+ print_part_with_lcs("add", new_line, lcs);
+ else
+ html_txt(new_line);
}
html("</td></tr>");
+ if (lcs)
+ free(lcs);
+ if (new_line)
+ free(new_line);
+ if (old_line)
+ free(old_line);
}
static void print_deferred_old_lines()
{
struct deferred_lines *iter_old, *tmp;
-
iter_old = deferred_old;
while (iter_old) {
print_ssdiff_line("del", iter_old->line_no,
- iter_old->line, -1, NULL);
+ iter_old->line, -1, NULL, 0);
tmp = iter_old->next;
free(iter_old);
iter_old = tmp;
@@ -155,11 +252,10 @@ static void print_deferred_old_lines()
static void print_deferred_new_lines()
{
struct deferred_lines *iter_new, *tmp;
-
iter_new = deferred_new;
while (iter_new) {
- print_ssdiff_line("add", -1, NULL, iter_new->line_no,
- iter_new->line);
+ print_ssdiff_line("add", -1, NULL,
+ iter_new->line_no, iter_new->line, 0);
tmp = iter_new->next;
free(iter_new);
iter_new = tmp;
@@ -169,6 +265,9 @@ static void print_deferred_new_lines()
static void print_deferred_changed_lines()
{
struct deferred_lines *iter_old, *iter_new, *tmp;
+ int n_old_lines = calc_deferred_lines(deferred_old);
+ int n_new_lines = calc_deferred_lines(deferred_new);
+ int individual_chars = (n_old_lines == n_new_lines ? 1 : 0);
iter_old = deferred_old;
iter_new = deferred_new;
@@ -176,14 +275,14 @@ static void print_deferred_changed_lines()
if (iter_old && iter_new)
print_ssdiff_line("changed", iter_old->line_no,
iter_old->line,
- iter_new->line_no, iter_new->line);
+ iter_new->line_no, iter_new->line,
+ individual_chars);
else if (iter_old)
print_ssdiff_line("changed", iter_old->line_no,
- iter_old->line, -1, NULL);
+ iter_old->line, -1, NULL, 0);
else if (iter_new)
print_ssdiff_line("changed", -1, NULL,
- iter_new->line_no, iter_new->line);
-
+ iter_new->line_no, iter_new->line, 0);
if (iter_old) {
tmp = iter_old->next;
free(iter_old);
@@ -202,14 +301,12 @@ void cgit_ssdiff_print_deferred_lines()
{
if (!deferred_old && !deferred_new)
return;
-
if (deferred_old && !deferred_new)
print_deferred_old_lines();
else if (!deferred_old && deferred_new)
print_deferred_new_lines();
else
print_deferred_changed_lines();
-
deferred_old = deferred_old_last = NULL;
deferred_new = deferred_new_last = NULL;
}
@@ -220,9 +317,7 @@ void cgit_ssdiff_print_deferred_lines()
void cgit_ssdiff_line_cb(char *line, int len)
{
char c = line[len - 1];
-
line[len - 1] = '\0';
-
if (line[0] == '@') {
current_old_line = line_from_hunk(line, '-');
current_new_line = line_from_hunk(line, '+');
@@ -232,7 +327,7 @@ void cgit_ssdiff_line_cb(char *line, int len)
if (deferred_old || deferred_new)
cgit_ssdiff_print_deferred_lines();
print_ssdiff_line("ctx", current_old_line, line,
- current_new_line, line);
+ current_new_line, line, 0);
current_old_line += 1;
current_new_line += 1;
} else if (line[0] == '+') {
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