diff options
Diffstat (limited to 'www/git.causal.agency/cgit/ui-ssdiff.c')
| -rw-r--r-- | www/git.causal.agency/cgit/ui-ssdiff.c | 420 |
1 files changed, 420 insertions, 0 deletions
diff --git a/www/git.causal.agency/cgit/ui-ssdiff.c b/www/git.causal.agency/cgit/ui-ssdiff.c new file mode 100644 index 00000000..af8bc9e0 --- /dev/null +++ b/www/git.causal.agency/cgit/ui-ssdiff.c @@ -0,0 +1,420 @@ +#include "cgit.h" +#include "ui-ssdiff.h" +#include "html.h" +#include "ui-shared.h" +#include "ui-diff.h" + +extern int use_ssdiff; + +static int current_old_line, current_new_line; +static int **L = NULL; + +struct deferred_lines { + int line_no; + char *line; + struct deferred_lines *next; +}; + +static struct deferred_lines *deferred_old, *deferred_old_last; +static struct deferred_lines *deferred_new, *deferred_new_last; + +static void create_or_reset_lcs_table(void) +{ + int i; + + if (L != NULL) { + memset(*L, 0, sizeof(int) * MAX_SSDIFF_SIZE); + return; + } + + // xcalloc will die if we ran out of memory; + // not very helpful for debugging + L = (int**)xcalloc(MAX_SSDIFF_M, sizeof(int *)); + *L = (int*)xcalloc(MAX_SSDIFF_SIZE, sizeof(int)); + + for (i = 1; i < MAX_SSDIFF_M; i++) { + L[i] = *L + i * MAX_SSDIFF_N; + } +} + +static char *longest_common_subsequence(char *A, char *B) +{ + int i, j, ri; + int m = strlen(A); + int n = strlen(B); + int tmp1, tmp2; + int lcs_length; + char *result; + + // We bail if the lines are too long + if (m >= MAX_SSDIFF_M || n >= MAX_SSDIFF_N) + return NULL; + + create_or_reset_lcs_table(); + + 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; + int len, res; + + buf1 = strchr(line, type); + if (buf1 == NULL) + return 0; + buf1 += 1; + buf2 = strchr(buf1, ','); + if (buf2 == NULL) + return 0; + len = buf2 - buf1; + buf2 = xmalloc(len + 1); + strlcpy(buf2, buf1, len + 1); + res = atoi(buf2); + free(buf2); + return res; +} + +static char *replace_tabs(char *line) +{ + char *prev_buf = line; + char *cur_buf; + size_t linelen = strlen(line); + int n_tabs = 0; + int i; + char *result; + size_t result_len; + + if (linelen == 0) { + result = xmalloc(1); + result[0] = '\0'; + return result; + } + + for (i = 0; i < linelen; i++) { + if (line[i] == '\t') + n_tabs += 1; + } + result_len = linelen + n_tabs * 8; + result = xmalloc(result_len + 1); + result[0] = '\0'; + + for (;;) { + cur_buf = strchr(prev_buf, '\t'); + if (!cur_buf) { + linelen = strlen(result); + strlcpy(&result[linelen], prev_buf, result_len - linelen + 1); + break; + } else { + linelen = strlen(result); + strlcpy(&result[linelen], prev_buf, cur_buf - prev_buf + 1); + linelen = strlen(result); + memset(&result[linelen], ' ', 8 - (linelen % 8)); + result[linelen + 8 - (linelen % 8)] = '\0'; + } + prev_buf = cur_buf + 1; + } + 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)); + item->line = xstrdup(line); + item->line_no = line_no; + item->next = NULL; + if (deferred_old) { + deferred_old_last->next = item; + deferred_old_last = item; + } else { + deferred_old = deferred_old_last = item; + } +} + +static void deferred_new_add(char *line, int line_no) +{ + struct deferred_lines *item = xmalloc(sizeof(struct deferred_lines)); + item->line = xstrdup(line); + item->line_no = line_no; + item->next = NULL; + if (deferred_new) { + deferred_new_last->next = item; + deferred_new_last = item; + } else { + deferred_new = deferred_new_last = item; + } +} + +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; + html("</span>"); + j += 1; + } + html_txt(c); + } + if (!same) + html("</span>"); +} + +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>\n"); + if (old_line_no > 0) { + struct diff_filespec *old_file = cgit_get_current_old_file(); + char *lineno_str = fmt("n%d", old_line_no); + char *id_str = fmt("id=%s#%s", is_null_oid(&old_file->oid)?"HEAD":oid_to_hex(old_rev_oid), lineno_str); + char *fileurl = cgit_fileurl(ctx.repo->url, "tree", old_file->path, id_str); + html("<td class='lineno'><a href='"); + html(fileurl); + htmlf("'>%s</a>", lineno_str + 1); + html("</td>"); + htmlf("<td class='%s'>", class); + free(fileurl); + } else if (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) { + if (lcs) + print_part_with_lcs("del", old_line, lcs); + else + html_txt(old_line); + } + + html("</td>\n"); + if (new_line_no > 0) { + struct diff_filespec *new_file = cgit_get_current_new_file(); + char *lineno_str = fmt("n%d", new_line_no); + char *id_str = fmt("id=%s#%s", is_null_oid(&new_file->oid)?"HEAD":oid_to_hex(new_rev_oid), lineno_str); + char *fileurl = cgit_fileurl(ctx.repo->url, "tree", new_file->path, id_str); + html("<td class='lineno'><a href='"); + html(fileurl); + htmlf("'>%s</a>", lineno_str + 1); + html("</td>"); + htmlf("<td class='%s'>", class); + free(fileurl); + } else if (new_line) + htmlf("<td class='lineno'></td><td class='%s'>", class); + else + htmlf("<td class='lineno'></td><td class='%s_dark'>", class); + if (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(void) +{ + 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, 0); + tmp = iter_old->next; + free(iter_old); + iter_old = tmp; + } +} + +static void print_deferred_new_lines(void) +{ + 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, 0); + tmp = iter_new->next; + free(iter_new); + iter_new = tmp; + } +} + +static void print_deferred_changed_lines(void) +{ + 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; + while (iter_old || iter_new) { + if (iter_old && iter_new) + print_ssdiff_line("changed", iter_old->line_no, + iter_old->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, 0); + else if (iter_new) + print_ssdiff_line("changed", -1, NULL, + iter_new->line_no, iter_new->line, 0); + if (iter_old) { + tmp = iter_old->next; + free(iter_old); + iter_old = tmp; + } + + if (iter_new) { + tmp = iter_new->next; + free(iter_new); + iter_new = tmp; + } + } +} + +void cgit_ssdiff_print_deferred_lines(void) +{ + 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; +} + +/* + * print a single line returned from xdiff + */ +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, '+'); + } + + if (line[0] == ' ') { + if (deferred_old || deferred_new) + cgit_ssdiff_print_deferred_lines(); + print_ssdiff_line("ctx", current_old_line, line, + current_new_line, line, 0); + current_old_line += 1; + current_new_line += 1; + } else if (line[0] == '+') { + deferred_new_add(line, current_new_line); + current_new_line += 1; + } else if (line[0] == '-') { + deferred_old_add(line, current_old_line); + current_old_line += 1; + } else if (line[0] == '@') { + html("<tr><td colspan='4' class='hunk'>"); + html_txt(line); + html("</td></tr>"); + } else { + html("<tr><td colspan='4' class='ctx'>"); + html_txt(line); + html("</td></tr>"); + } + line[len - 1] = c; +} + +void cgit_ssdiff_header_begin(void) +{ + current_old_line = -1; + current_new_line = -1; + html("<tr><td class='space' colspan='4'><div></div></td></tr>"); + html("<tr><td class='head' colspan='4'>"); +} + +void cgit_ssdiff_header_end(void) +{ + html("</td></tr>"); +} + +void cgit_ssdiff_footer(void) +{ + if (deferred_old || deferred_new) + cgit_ssdiff_print_deferred_lines(); + html("<tr><td class='foot' colspan='4'></td></tr>"); +} |